Digital smart internal fixation surgery for coronal process basal fracture with normal joint spaces or radius-shortening: Occult factor of radius-ulna load sharing

BACKGROUND

Reasonable postoperative humeroradial and humeroulnar joint spaces maybe an important indicator in biomechanical stability of smart internal fixation surgery for coronoid process basal fractures (CPBF). The aim of this study is to compare elbow articular stresses and elbow-forearm stability under smart internal fixations for the CPBF between normal elbow joint spaces and radius-shortening, and to determine the occult factor of radius-ulna load sharing.

METHODS

CT images of 70 volunteers with intact elbow joints were retrospectively collected for accurate three-dimensional reconstruction to measure the longitudinal and transverse joint spaces. Two groups of ten finite element (FE) models were established prospectively between normal joint space and radius-shortening with 2.0 mm, including intact elbow joint and forearm, elbow-forearm with CPBF trauma, anterior or posterior double screws-cancellous bone fixation, mini-plate-cancellous bone fixation. Three sets of physiological loads (compression, valgus, varus) were used for FE intelligent calculation, FE model verification, and biomechanical and motion analysis.

RESULTS

The stress distribution between coronoid process and radial head, compression displacements and valgus angles of elbow-forearm in the three smart fixation models of the normal joint spaces were close to those of corresponding intact elbow model, but were significantly different from those of preoperative CPBF models and fixed radius-shortening models. The maximum stresses of three smart fixation instrument models of normal joint spaces were significantly smaller than those of the corresponding fixed radius-shortening models.

CONCLUSIONS

On the basis of the existing trauma of the elbow-forearm system in clinical practice, which is a dominant factor affecting radius-ulna load sharing, the elbow joint longitudinal space has been found to be the occult factor affecting radius-ulna load sharing. The stability and load sharing of radius and ulna after three kinds of smart fixations of the CPBF is not only related to the anatomical and biomechanical stability principles of smart internal fixations, but also closely related to postoperative elbow joint longitudinal space.

Search for Heavy Neutral Leptons in Electron-Positron and Neutral-Pion Final States with the MicroBooNE Detector

We present the first search for heavy neutral leptons (HNLs) decaying into νe^{+}e^{-} or νπ^{0} final states in a liquid-argon time projection chamber using data collected with the MicroBooNE detector. The data were recorded synchronously with the NuMI neutrino beam from Fermilab's main injector corresponding to a total exposure of 7.01×10^{20} protons on target. We set upper limits at the 90% confidence level on the mixing parameter |U_{μ4}|^{2} in the mass ranges 10≤m_{HNL}≤150  MeV for the νe^{+}e^{-} channel and 150≤m_{HNL}≤245  MeV for the νπ^{0} channel, assuming |U_{e4}|^{2}=|U_{τ4}|^{2}=0. These limits represent the most stringent constraints in the mass range 35 Collapse

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Affiliation(s)

P Abratenko Tufts University, Medford, Massachusetts 02155, USA
O Alterkait Tufts University, Medford, Massachusetts 02155, USA
D Andrade Aldana Illinois Institute of Technology (IIT), Chicago, Illinois 60616, USA
L Arellano The University of Manchester, Manchester M13 9PL, United Kingdom
J Asaadi University of Texas, Arlington, Texas 76019, USA
A Ashkenazi Tel Aviv University, Tel Aviv, Israel, 69978
S Balasubramanian Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
B Baller Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
G Barr University of Oxford, Oxford OX1 3RH, United Kingdom
D Barrow University of Oxford, Oxford OX1 3RH, United Kingdom
J Barrow Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA Tel Aviv University, Tel Aviv, Israel, 69978
V Basque Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
O Benevides Rodrigues Illinois Institute of Technology (IIT), Chicago, Illinois 60616, USA
S Berkman Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA Michigan State University, East Lansing, Michigan 48824, USA
A Bhanderi The University of Manchester, Manchester M13 9PL, United Kingdom
A Bhat University of Chicago, Chicago, Illinois 60637, USA
M Bhattacharya Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
M Bishai Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
A Blake Lancaster University, Lancaster LA1 4YW, United Kingdom
B Bogart University of Michigan, Ann Arbor, Michigan 48109, USA
T Bolton Kansas State University (KSU), Manhattan, Kansas 66506, USA
J Y Book Harvard University, Cambridge, Massachusetts 02138, USA
M B Brunetti University of Warwick, Coventry CV4 7AL, United Kingdom
L Camilleri Columbia University, New York, New York 10027, USA
Y Cao The University of Manchester, Manchester M13 9PL, United Kingdom
D Caratelli University of California, Santa Barbara, California 93106, USA
F Cavanna Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
G Cerati Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
A Chappell University of Warwick, Coventry CV4 7AL, United Kingdom
Y Chen SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
J M Conrad Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA
M Convery SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
L Cooper-Troendle University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
J I Crespo-Anadón Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid E-28040, Spain
R Cross University of Warwick, Coventry CV4 7AL, United Kingdom
M Del Tutto Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
S R Dennis University of Cambridge, Cambridge CB3 0HE, United Kingdom
P Detje University of Cambridge, Cambridge CB3 0HE, United Kingdom
A Devitt Lancaster University, Lancaster LA1 4YW, United Kingdom
R Diurba Universität Bern, Bern CH-3012, Switzerland
Z Djurcic Argonne National Laboratory (ANL), Lemont, Illinois 60439, USA
R Dorrill Illinois Institute of Technology (IIT), Chicago, Illinois 60616, USA
K Duffy University of Oxford, Oxford OX1 3RH, United Kingdom
S Dytman University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
B Eberly University of Southern Maine, Portland, Maine 04104, USA
P Englezos Rutgers University, Piscataway, New Jersey 08854, USA
A Ereditato University of Chicago, Chicago, Illinois 60637, USA Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
J J Evans The University of Manchester, Manchester M13 9PL, United Kingdom
R Fine Los Alamos National Laboratory (LANL), Los Alamos, New Mexico 87545, USA
O G Finnerud The University of Manchester, Manchester M13 9PL, United Kingdom
W Foreman Illinois Institute of Technology (IIT), Chicago, Illinois 60616, USA
B T Fleming University of Chicago, Chicago, Illinois 60637, USA
D Franco University of Chicago, Chicago, Illinois 60637, USA
A P Furmanski University of Minnesota, Minneapolis, Minnesota 55455, USA
F Gao University of California, Santa Barbara, California 93106, USA
D Garcia-Gamez Universidad de Granada, Granada E-18071, Spain
S Gardiner Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
G Ge Columbia University, New York, New York 10027, USA
S Gollapinni Los Alamos National Laboratory (LANL), Los Alamos, New Mexico 87545, USA
E Gramellini The University of Manchester, Manchester M13 9PL, United Kingdom
P Green University of Oxford, Oxford OX1 3RH, United Kingdom
H Greenlee Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
L Gu Lancaster University, Lancaster LA1 4YW, United Kingdom
W Gu Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
R Guenette The University of Manchester, Manchester M13 9PL, United Kingdom
P Guzowski The University of Manchester, Manchester M13 9PL, United Kingdom
L Hagaman University of Chicago, Chicago, Illinois 60637, USA
O Hen Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA
C Hilgenberg University of Minnesota, Minneapolis, Minnesota 55455, USA
G A Horton-Smith Kansas State University (KSU), Manhattan, Kansas 66506, USA
Z Imani Tufts University, Medford, Massachusetts 02155, USA
B Irwin University of Minnesota, Minneapolis, Minnesota 55455, USA
M Ismail University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
C James Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
X Ji Nankai University, Nankai District, Tianjin 300071, China
J H Jo Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
R A Johnson University of Cincinnati, Cincinnati, Ohio 45221, USA
Y-J Jwa Columbia University, New York, New York 10027, USA
D Kalra Columbia University, New York, New York 10027, USA
N Kamp Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA
G Karagiorgi Columbia University, New York, New York 10027, USA
W Ketchum Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
M Kirby Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
T Kobilarcik Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
I Kreslo Universität Bern, Bern CH-3012, Switzerland
M B Leibovitch University of California, Santa Barbara, California 93106, USA
I Lepetic Rutgers University, Piscataway, New Jersey 08854, USA
J-Y Li University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
K Li Wright Laboratory, Department of Physics, Yale University, New Haven, Connecticut 06520, USA
Y Li Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
K Lin Rutgers University, Piscataway, New Jersey 08854, USA
B R Littlejohn Illinois Institute of Technology (IIT), Chicago, Illinois 60616, USA
H Liu Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
W C Louis Los Alamos National Laboratory (LANL), Los Alamos, New Mexico 87545, USA
X Luo University of California, Santa Barbara, California 93106, USA
C Mariani Center for Neutrino Physics, Virginia Tech, Blacksburg, Viriginia 24061, USA
D Marsden The University of Manchester, Manchester M13 9PL, United Kingdom
J Marshall University of Warwick, Coventry CV4 7AL, United Kingdom
N Martinez Kansas State University (KSU), Manhattan, Kansas 66506, USA
D A Martinez Caicedo South Dakota School of Mines and Technology (SDSMT), Rapid City, South Dakota 57701, USA
S Martynenko Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
A Mastbaum Rutgers University, Piscataway, New Jersey 08854, USA
I Mawby University of Warwick, Coventry CV4 7AL, United Kingdom
N McConkey University College London, London WC1E 6BT, United Kingdom
V Meddage Kansas State University (KSU), Manhattan, Kansas 66506, USA
J Micallef Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA Tufts University, Medford, Massachusetts 02155, USA
K Miller University of Chicago, Chicago, Illinois 60637, USA
A Mogan Colorado State University, Fort Collins, Colorado 80523, USA
T Mohayai Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA Indiana University, Bloomington, Indiana 47405, USA
M Mooney Colorado State University, Fort Collins, Colorado 80523, USA
A F Moor University of Cambridge, Cambridge CB3 0HE, United Kingdom
C D Moore Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
L Mora Lepin The University of Manchester, Manchester M13 9PL, United Kingdom
M M Moudgalya The University of Manchester, Manchester M13 9PL, United Kingdom
S Mulleriababu Universität Bern, Bern CH-3012, Switzerland
D Naples University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
A Navrer-Agasson The University of Manchester, Manchester M13 9PL, United Kingdom
N Nayak Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
M Nebot-Guinot University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
J Nowak Lancaster University, Lancaster LA1 4YW, United Kingdom
N Oza Columbia University, New York, New York 10027, USA
O Palamara Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
N Pallat University of Minnesota, Minneapolis, Minnesota 55455, USA
V Paolone University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
A Papadopoulou Argonne National Laboratory (ANL), Lemont, Illinois 60439, USA
V Papavassiliou New Mexico State University (NMSU), Las Cruces, New Mexico 88003, USA
H B Parkinson University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
S F Pate New Mexico State University (NMSU), Las Cruces, New Mexico 88003, USA
N Patel Lancaster University, Lancaster LA1 4YW, United Kingdom
Z Pavlovic Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
E Piasetzky Tel Aviv University, Tel Aviv, Israel, 69978
I Pophale Lancaster University, Lancaster LA1 4YW, United Kingdom
X Qian Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
J L Raaf Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
V Radeka Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
A Rafique Argonne National Laboratory (ANL), Lemont, Illinois 60439, USA
M Reggiani-Guzzo University of Edinburgh, Edinburgh EH9 3FD, United Kingdom The University of Manchester, Manchester M13 9PL, United Kingdom
L Ren New Mexico State University (NMSU), Las Cruces, New Mexico 88003, USA
L Rochester SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
J Rodriguez Rondon South Dakota School of Mines and Technology (SDSMT), Rapid City, South Dakota 57701, USA
M Rosenberg Tufts University, Medford, Massachusetts 02155, USA
M Ross-Lonergan Los Alamos National Laboratory (LANL), Los Alamos, New Mexico 87545, USA
C Rudolf von Rohr Universität Bern, Bern CH-3012, Switzerland
I Safa Columbia University, New York, New York 10027, USA
G Scanavini Wright Laboratory, Department of Physics, Yale University, New Haven, Connecticut 06520, USA
D W Schmitz University of Chicago, Chicago, Illinois 60637, USA
A Schukraft Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
W Seligman Columbia University, New York, New York 10027, USA
M H Shaevitz Columbia University, New York, New York 10027, USA
R Sharankova Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
J Shi University of Cambridge, Cambridge CB3 0HE, United Kingdom
E L Snider Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
M Soderberg Syracuse University, Syracuse, New York 13244, USA
S Söldner-Rembold The University of Manchester, Manchester M13 9PL, United Kingdom
J Spitz University of Michigan, Ann Arbor, Michigan 48109, USA
M Stancari Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
J St John Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
T Strauss Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
A M Szelc University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
W Tang University of Tennessee, Knoxville, Tennessee 37996, USA
N Taniuchi University of Cambridge, Cambridge CB3 0HE, United Kingdom
K Terao SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
C Thorpe Lancaster University, Lancaster LA1 4YW, United Kingdom The University of Manchester, Manchester M13 9PL, United Kingdom
D Torbunov Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
D Totani University of California, Santa Barbara, California 93106, USA
M Toups Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
Y-T Tsai SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
J Tyler Kansas State University (KSU), Manhattan, Kansas 66506, USA
M A Uchida University of Cambridge, Cambridge CB3 0HE, United Kingdom
T Usher SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
B Viren Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
M Weber Universität Bern, Bern CH-3012, Switzerland
H Wei Louisiana State University, Baton Rouge, Louisiana 70803, USA
A J White University of Chicago, Chicago, Illinois 60637, USA
S Wolbers Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
T Wongjirad Tufts University, Medford, Massachusetts 02155, USA
M Wospakrik Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
K Wresilo University of Cambridge, Cambridge CB3 0HE, United Kingdom
W Wu University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
E Yandel University of California, Santa Barbara, California 93106, USA
T Yang Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
L E Yates Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
H W Yu Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
G P Zeller Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
J Zennamo Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
C Zhang Brookhaven National Laboratory (BNL), Upton, New York 11973, USA

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[Secondary non-tuberculous mycobacterium infection in patients with bronchiectasis caused by Marfan syndrome]

In this article, we reported a 28-year-old female patient who presented with intermittent hemoptysis, cough, and sputum production. Laboratory tests showed no abnormalities in the blood counts or inflammatory markers, and the sputum cultures were negative. A chest computed tomography scan showed bronchiectasis associated with infection in the middle and lower lobes of the right lung and right pleural thickening. We performed bronchoalveolar lavage by bronchoscopy in the dorsal segment of the right lower lobe and found Mycobacterium avium intracellulare complex (MAC) by Next Generation Sequencing (NGS) of bronchoalveolar lavage fluid (BALF). The patient's symptoms improved significantly after anti-mycobacterium treatment and the extent of infection was reduced on imaging. To further identify the cause of bronchiectasis, the patient is tall and thin, with slender limbs. Cardiac color ultrasound showed the widening of aortic sinus. Her genetic testing of blood samples revealed the gene mutation in the FBN1 gene (c.4349G>A). Based on these results, she was diagnosed with Marfan syndrome.

[Serology and genomic analysis of para-Bombay individuals in a hospital in Hunan Province]

To investigate the serological and genetic characteristics of para-Bombay patients in a hospital in Hunan Province. A retrospective analysis was conducted on the blood type results of 175 439 hospitalized patients born in Hunan Province from the Third Xiangya Hospital, Central South University from 2016 to 2021. Phenotypes of ABO blood group was analyzed by blood group serology, and molecular biological methods were used to analyze the genotype, including ABO genotyping by polymerase chain reaction-sequence specific primers (PCR-SSP) and fucosyltransferase 1 (FUT1) and fucosyltransferase 2 (FUT2) gene sequencing. The results showed that 3 cases of Ah and 1 case of Bh were detected. FUT1 sequencing showed that there were 2 cases of h3h3, 1 case of h1h1 and 1 case of h302h1, of which h302 (c.302C>T) was the first discovered mutation. FUT2 sequencing revealed that 4 cases were all Se357Se357. The pedigree study showed that the inheritance of para-Bombay blood group was consistent with autosomal dominant inheritance. In conclusion, the FUT1 gene mutations leading to para-Bombay blood group mainly include h3, h1 and h302, of which h3 mutation is the most common.

Identification and adaptive evolution analysis of glutaredoxin genes in Populus spp

Glutaredoxin (GRX) is a class of small redox proteins widely involved in cellular redox homeostasis and the regulation of various cellular processes. The role of GRX gene in the differentiation of Populus spp. is rarely reported. We compared the similarities and differences of GRX genes among four sections of poplar using bioinformatics, corrected the annotations of some GRX genes, and focused on analysing their transcript profiling and adaptive evolution in Populus spp. A total of 219 GRX genes were identified in four sections of poplar, among which annotations for 13 genes were corrected. Differences in GRX genes were found between sect. Turanga, represented by P. euphratica, and other poplar sections. Most notably, P. euphratica had the smallest number of duplication events for GRX genes (n = 9) and no tandem duplications, whereas there were >25 duplication events for all other poplars. Furthermore, we detected 18 pairs of GRX genes under positive selection pressure in various sections of poplar, and identified two groups of GRX genes in the Salicaceae that potentially underwent positive selection. Expression profiling results showed that the PtrGRX34 and its orthologous genes were upregulated under stress treatments. In summary, the GRX gene family underwent expansion during poplar differentiation, and some genes underwent rapid evolution during this process, which may be beneficial for Populus spp. to adapt to environmental changes. This study may provide more insights into the molecular mechanisms of Populus spp. adaptation to environmental changes and the adaptive evolution of GRX genes.

[Molecular epidemiology and clinical characteristics of six cases of CA-MRSA pneumonia after influenza]

Objective: To summarize and analyze the strains' molecular epidemiology and clinical characteristics of 6 strains of post-influenza community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) pneumonia. Methods: Six cases of CA-MRSA pneumonia after influenza from 2014 to 2022 were retrospectively collected and CA-MRSA strains from each patient were cultured. Then, SCCmec typing, MLST typing, and spa typing were performed on the samples, which also included the procedures for the detection of virulence factors. Antibiotic susceptibility test was then performed on all 6 strains. Results: ST59-t437-Ⅳ was the predominant type in all the strains of CA-MRSA(2/6). Leukocidin (PVL) was detected in 5 cases, and hemolysin α (HLAα) and phenol soluble regulatory protein α (PSMα) were detected in 6 cases. Five of the cases included in this study were diagnosed with severe pneumonia. In terms of treatment, 4 cases received antiviral therapy, and 5 patients with severe pneumonia received anti-infection treatment with vancomycin as the first choice and were discharged after improvement of their condition. Conclusions: The molecular types and virulence factors of CA-MRSA after influenza infection could vary considerably. Our experiments also showed that secondary CA-MRSA infection after influenza was more common in young people with no underlying diseases and could cause severe pneumonia. Vancomycin and linezolid were the first-line drugs for treating CA-MRSA infection and were highly effective in improving the condition of diagnosed patients. We highlighted the importance of referring patients with severe pneumonia after influenza for etiological tests to determine whether they had CA-MRSA infection, so that they could be properly treated with anti-influenza agents and receive appropriate anti-CA-MRSA infection treatment.

A single-arm, multicenter, phase II trial of osimertinib in patients with epidermal growth factor receptor exon 18 G719X, exon 20 S768I, or exon 21 L861Q mutations

BACKGROUND

For patients with stage IV non-small-cell lung cancer with epidermal growth factor receptor (EGFR) exon 19 deletions and exon 21 L858R mutations, osimertinib is the standard of care. Investigating the activity and safety of osimertinib in patients with EGFR exon 18 G719X, exon 20 S768I, or exon 21 L861Q mutations is of clinical interest.

PATIENTS AND METHODS

Patients with stage IV non-small-cell lung cancer with confirmed EGFR exon 18 G719X, exon 20 S768I, or exon 21 L861Q mutations were eligible. Patients were required to have measurable disease, an Eastern Cooperative Oncology Group performance status of 0 or 1, and adequate organ function. Patients were required to be EGFR tyrosine kinase inhibitor-naive. The primary objective was objective response rate, and secondary objectives were progression-free survival, safety, and overall survival. The study used a two-stage design with a plan to enroll 17 patients in the first stage, and the study was terminated after the first stage due to slow accrual.

RESULTS

Between May 2018 and March 2020, 17 patients were enrolled and received study therapy. The median age of patients was 70 years (interquartile range 62-76), the majority were female (n = 11), had a performance status of 1 (n = 10), and five patients had brain metastases at baseline. The objective response rate was 47% [95% confidence interval (CI) 23% to 72%], and the radiographic responses observed were partial response (n = 8), stable disease (n = 8), and progressive disease (n = 1). The median progression-free survival was 10.5 months (95% CI 5.0-15.2 months), and the median OS was 13.8 months (95% CI 7.3-29.2 months). The median duration on treatment was 6.1 months (range 3.6-11.9 months), and the most common adverse events (regardless of attribution) were diarrhea, fatigue, anorexia, weight loss, and dyspnea.

CONCLUSIONS

This trial suggests osimertinib has activity in patients with these uncommon EGFR mutations.

A new prognostic model for brain metastases of specific primary tumors with stereotactic radiotherapy

PURPOSE

Stereotactic radiotherapy (SRT) was widely used in brain metastases (BM), especially in oligometastases. It is imperative to develop a new prognostic score to predict the overall survival (OS) of brain metastases based on prognostic factors for specific primary tumors.

MATERIAL AND METHOD

One hundred and ninety-seven patients were involved in the training cohort to develop a new prognostic score to predict the overall survival (OS) of brain metastases for specific primary tumors. Independent prognostic factors were confirmed using a Cox regression model. The score was developed based on clinical prognostic factors of OS with Cox proportional hazards model. The result was validated in another cohort with 56 participants to evaluate the performance of the score.

RESULTS

One hundred and ninety-seven patients with 329 brain metastases received SRT. For NSCLC, the significant prognostic factors were extracranial metastases, target therapy and number of brain metastases. For gastrointestinal cancer, the significant prognostic factors were target therapy and number of brain metastases.

CONCLUSION

The prognostic factors scores were varied by the histologic types which can be used to efficiently stratify for selected patients with brain-metastasis.

Focal opening of the neuronal plasma membrane by shock-induced bubble collapse for drug delivery: a coarse-grained molecular dynamics simulation

Cell permeabilization using shock-induced bubble collapse provides an attractive choice for drug delivery systems. In this work, based on a realistically human brain plasma membrane (PM) model, we investigated the focal opening of this complex model by the jet from cavitation, focusing on the effect of characteristic membrane components, particle velocity (u_p) and bubble diameters (D). Both high levels of cholesterol and specific cerebrosides in the PM model limit the pore opening of cavitation jets. Sphingomyelin is the opposite, but has little effect due to its low content. Two adjustable parameters of u_p and D can be coupled to control the opening size. The relationship between them and the maximum pore area was provided for the first time. The maximum pore area increases with the u_p (or the impulse that is positively related to u_p) in the low-speed range, which agrees with the experimentally observed impulse determinism. However, the maximum area drops in the high-speed range. Combined with D, we proposed that the jet size determines the pore size, not the impulse. Larger bubbles that can create a larger pore in the membrane have a larger jet size, but their impulse is relatively small. Finally, the recovery simulation shows that the membrane with a small pore can be quickly recovered within 300 ps, while that with a larger pore did not recover until 2 μs. These rules from this work may be helpful to optimize the choice of shock waves for the delivery of different drugs across membranes.

Extreme Membrane Tensile Loads Induce Half-Activation of the Thermosensitive TRPV1 Channel

Transient receptor potential (TRP) channels are sensors for a wide range of cellular and environmental signals, but elucidating how these channels convert a wide range of physical and chemical stimuli into channel opening is essential to understanding their normal function. Here, half-activation of thermosensitive TRPV1 channel under extreme membrane stretching from blast loads was provided by molecular dynamics simulations. The results show that such extreme membrane stretch loading will only lead to half-activation of the TRPV1 channel: that is, the upper gate is open for high-speed stretching (>15m/s), but the lower gate is still closed. The corresponding activation threshold also depends on both the tensile speed and the area strain. This means that the direct mechanical gating of TRP channels in one step is unlikely to occur.

Retention of Intrafibrillar Minerals Improves Resin-Dentin Bond Durability

The concept of extrafibrillar demineralization involves selective removal of apatite crystallites from the extrafibrillar spaces of mineralized dentin without disturbing the intrafibrillar minerals within collagen. This helps avoiding activation of endogenous proteases and enables air-drying of partially demineralized dentin without causing collapse of completely demineralized collagen matrix that adversely affects resin infiltration. The objective of the present study was to evaluate the potential of quaternized carboxymethyl chitosan (QCMC)-based extrafibrillar demineralization in improving resin-dentin bond durability. Isothermal titration calorimetry indicated that QCMC synthesized by quaternization of O-carboxymethyl chitosan had moderate affinity for Ca²⁺ (binding constant: 8.9 × 10⁴ M^-1). Wet and dry bonding with the QCMC-based demineralization produced tensile bond strengths equivalent to the phosphoric acid (H₃PO₄)-based etch-and-rinse technique. Those bond strengths were maintained after thermocycling. Amide I and PO₄^3- mappings of QCMC-conditioned dentin were performed with atomic force microscope-infrared spectroscopy (AFM-IR). Whereas H₃PO₄-etched dentin exhibited an extensive reduction in PO₄^3- signals corresponding to apatite depletion, QCMC-conditioned dentin showed scattered dark areas and bright PO₄^3- streak signals. The latter were consistent with areas identified as collagen fibrils in the amide I mapping and were suggestive of the presence of intrafibrillar minerals in QCMC-conditioned dentin. Young's modulus mapping of QCMC-demineralized dentin obtained by AFM-based amplitude modulation-frequency modulation recorded moduli that were the same order of magnitude as those in mineralized dentin and at least 1 order higher than H₃PO₄-etched dentin. In situ zymography of the gelatinolytic activity within hybrid layers created with QCMC conditioning revealed extremely low signals before and after thermocycling, compared with H₃PO₄-etched dentin for both wet and dry bonding. Confocal laser scanning microscopy identified the antibacterial potential of QCMC against Streptococcus mutans and Enterococcus faecalis biofilms. Taken together, the QCMC-based demineralization retains intrafibrillar minerals, preserves the elastic modulus of collagen fibrils, reduces endogenous proteolytic activity, and inhibits bacteria biofilms to extend dentin bond durability.

A Novel Gating Mechanism of Aquaporin-4 Water Channel Mediated by Blast Shockwaves for Brain Edema

As the principal water channel in the brain, aquaporin-4 (AQP4) plays a vital role in brain edema, but its role in blast brain edema is unclear. On the basis of molecular simulations, we reveal the atomically detailed picture of AQP4 in response to blast shockwaves. The results show that the shockwave alone closes the AQP4 channel; however, shock-induced bubble collapse opens it. The jet from bubble collapse forcefully increases the distance between helices and the tilt angles of six helices relative to the membrane vertical direction in a very short time. The average channel size increases about 2.6 times, and the water flux rate is nearly 20 times higher than for normal states. It is responsible for abnormal water transport and a potential cause of acute blast brain edema. Additionally, the open AQP4 channel quickly returns to its normal state, which is in turn helpful for edema absorption. Thus, a novel gating mechanism for AQP4 related to the secondary structure change has been provided, which is different from the previous residue-mediated gating mechanism.

The effects of molecular weight and orientation on the membrane permeation and partitioning of polycyclic aromatic hydrocarbons: a computational study

Membrane permeation and the partitioning of polycyclic aromatic hydrocarbons (PAHs) are crucial aspects affecting their carcinogenicity and mutagenicity. However, a clear understanding of these processes is still rare due to the difficulty of determining the details experimentally. Here, the interactions between PAHs and lipid bilayers were studied by molecular simulations, mainly to check the influence of molecular weight and orientation. The liposome-water partition coefficient (K_LW), transmembrane time (τ), and permeability coefficient (P) of the PAHs were calculated by integrating free energy profiles from umbrella sampling. For selected PAHs, the membrane adsorption is a spontaneous process. The preferred location is near the CC bond and the orientation is related to the molecular structure. The P values of all the PAHs are basically the same order of magnitude, which means that the molecular weight contributes little to the process. As for K_LW and τ, they show obvious increases with different molecular weights. Unconstrained simulations showed that a flat orientation on the membrane surface would prevent PAHs from being transported through the membrane. Highly hydrophobic driving forces are not always good for the absorption of PAHs, especially the formation of aggregates. In addition, the orientations and energetic barriers of PAHs near the midplane of the lipid bilayer explain the different transitions of high- and low-weight PAHs. This work provides molecular level details relating to the interactions of PAHs with lipid membranes, with significance for understanding the health effects of PAHs.

[Clinical characteristics of human adenovirus infection in hospitalized children with acute respiratory infection in Beijing]

Objective: To compare the clinical characteristics of different types of human adenovirus (HAdV) infection in hospitalized children with acute respiratory infection in Beijing, and to clarify the clinical necessity of adenovirus typing. Methods: In a cross-sectional study, 9 022 respiratory tract specimens collected from hospitalized children with acute respiratory infection from November 2017 to October 2019 in Affiliated Children's Hospital, Capital Institute of Pediatrics were screened for HAdV by direct immunofluorescence (DFA) and (or) nucleic acid detection. Then the Penton base, Hexon and Fiber gene of HAdV were amplified from HAdV positive specimens to confirm their HAdV types by phylogenetic tree construction. Clinical data such as laboratory results and imaging data were analyzed for children with predominate type HAdV infection using t, U, or χ² test. Results: There were 392 cases (4.34%) positive for HAdV among 9 022 specimens from hospitalized children with acute respiratory infection. Among those 205 cases who were successfully typed, 131 were male and 74 were female, age of 22.6 (6.7, 52.5) months,102 cases (49.76%) were positive for HAdV-3 and 86 cases (41.95%), HAdV-7, respectively, while 17 cases were confirmed as HAdV-1, 2, 4, 6, 14 or 21. In comparison of clinical characteristics between the predominate HAdV type 7 and 3 infection, significant differences were shown in proportions of children with wheezing (10 cases (11.63%) vs. 25 cases (24.51%)), white blood cell count >15 ×10⁹/L (4 cases (4.65%) vs.14 cases (13.73%)), white blood cell count <5×10⁹/L (26 cases (30.23%) vs.11 cases (10.78%)), procalcitonin level>0.5 mg/L (43 cases (50.00%) vs. 29 cases (28.43%)), multilobar infiltration (45 cases (52.33%) vs.38 cases (37.25%)), pleural effusion (23 cases (26.74%) vs. 10 cases (9.80%)), and severe adenovirus pneumonia (7 cases (8.14%) vs. 2 cases (1.96%)) with χ²=5.11, 4.44, 11.16, 9.19, 4.30, 9.25, 3.91 and P=0.024, 0.035, 0.001, 0.002, 0.038, 0.002, 0.048, respectively, and also in length of hospital stay (11 (8, 15) vs. 7 (5, 13) d, Z=3.73, P<0.001). Conclusions: HAdV-3 and 7 were the predominate types of HAdV infection in hospitalized children with acute respiratory tract infection in Beijing. Compared with HAdV-3 infection, HAdV-7 infection caused more obvious inflammatory reaction, more severe pulmonary symptoms, longer length of hospital stay, suggesting the clinical necessity of further typing of HAdVs.

Effects of Non-Invasive Brain Stimulation on Alzheimer's Disease

BACKGROUND

Previous meta-analyses did not explore the immediate and long-term effect of non-invasive brain stimulation (NIBS) on different cognitive domains in Alzheimer's disease (AD). The meta-analysis aimed to assess the therapy effect of repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) on different cognitive domains in AD in randomized controlled trials (RCTs).

METHODS

Studies published before December 2021 and exploring therapy effect of rTMS, tDCS on different cognitive domains in AD were searched in the following databases: PubMed and Web of Science. We used STATA 12.0 software to compute the standard mean difference (SMD) and a 95% confidence interval (CI).

RESULTS

The present study included 16 articles (including 372 AD patients treated with rTMS and 310 treated with sham rTMS) for rTMS and 11 articles (including 152 AD patients treated with tDCS and 134 treated with sham tDCS) for tDCS. The present study showed better immediate and long-term general cognitive function increase effects in AD given rTMS, compared to those given sham rTMS with random effects models (immediate effect: SMD = 2.07, 95% CI = 0.37 to 3.77, I2 = 97.8%, p < 0.001; long-term effect: SMD = 5.04, 95% CI = 2.25 to 7.84, I2 = 97.8%, p < 0.001). The present study showed no significant immediate and long-term effects of rTMS on attention, executive, language and memory functions. In addition, the present study showed no significant difference in immediate or long-term effects of tDCS on general cognitive function, attention, language or memory functions between tDCS group and sham tDCS group.

CONCLUSIONS

RTMS was an effective treatment technique for general cognitive function in AD, whereas tDCS showed no significant therapy effect on cognitive function in AD. More large-scale studies were essential to explore the effect of NIBS on various cognitive function in AD.

Prostacyclins and pulmonary arterial hypertension in children

OBJECTIVE

Despite its low incidence, pulmonary hypertension in children places a substantial burden on families and society because survival can be shorter than 10 months and treatment options are limited and ineffective. Drugs to treat pulmonary hypertension include endothelin antagonists, phosphodiesterase type 5 inhibitors and prostacyclin, which is the most widely used to treat pediatric pulmonary hypertension. The main aim of this study was to provide a comprehensive overview of the advantages and disadvantages of prostacyclin and its analogs for treating pulmonary hypertension in children.

MATERIALS AND METHODS

To retrieve a thorough collection of studies, we performed a search in PubMed using the following combination of keywords: (Prostacyclins) or (Epoprostenol) or (Iloprost) or (Treprostinil) or (Beraprost), (children) and (pulmonary arterial hypertension). The time limits used for the search were December 1983 to May 2021.

RESULTS

The search retrieved a total of 238 articles. Titles and abstracts of articles were screened for relevance, and all relevant articles published in English were included.

CONCLUSIONS

Epoprostenol can be effective against severe pulmonary hypertension. Iloprost can treat severe persistent pulmonary hypertension in newborns and inhaled iloprost can be used in pulmonary vasoreactivity testing. Treprostinil is a long-acting prostacyclin analog, and it shows the highest antiproliferative activity among prostacyclins. Beraprost may be effective in premature infants, but available evidence comes from only one patient, so more clinical testing is needed.

[Current status and research advances on the use of assisted traction technique in endoscopic full-thickness resection]

Endoscopic full-thickness resection (EFTR) allows completely resecting deep submucosal tumors (SMTs) in the gastrointestinal wall, which has a broad application prospect in clinic. However, its application and promotion are limited by complex surgical procedures and high surgical risk. Various auxiliary traction techniques are expected to reduce the operation difficulty and risk of EFTR and improve its operative success rate. To provide a reference for clinicians, we summarize various auxiliary traction techniques in EFTR in this article. The clip-with-line method is simple to operate and widely used, whereas its traction is limited and there is a risk of clip falling off. The snare traction method and the clip-snare traction method has advantage of large traction force, but its thrust is affected by the hardness of snare. The traction point of the grasping forceps traction method is flexible and easy to adjust. Nevertheless, it requires the use of a dual-channel upper endoscope, which is difficult to operate. The transparent cap traction method and the full-thickness resection device traction method takes a short time and is easy to promote, whereas the resectable lesion is limited, and the size of the lesion may affect the success rate. In contrast, the suture loop needle-T-tag tissue anchors assisted method has a large resection range, but the operation is complicated and the feasibility has not been verified. The robot-assisted method has flexible operation and excellent visualization, whereas it is expensive and difficult to operate. There is no report of the application of magnetic anchor technology in EFTR, but it may have good application prospects in the auxiliary traction of EFTR.

Dynamic contrast-enhanced magnetic resonance imaging: A novel approach to assessing treatment in locally advanced esophageal cancer patients

Aims

This study aims to investigate the potential application of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to predict concurrent chemoradiation (CRT) in locally advanced esophageal carcinoma.

Patients and Methods

This study involved 33 patients with locally advanced esophageal cancer and treated with CRT. The patients underwent DCE-MRI before CRT (pre) and 3 weeks after starting CRT (mid). The patients were categorized into two groups: complete response (CR) and non-complete response (non-CR) after 3 months of treatment. The quantitative parameters of DCE-MRI (K^trans, Kep, and Ve), the changes and ratios of parameters (ΔK^trans, ΔKep, ΔVe, rΔK^trans, rΔKep, and rΔVe), and the relative ratio in the tumor area and a normal tube wall (rK^trans, rKep, and rVe) were calculated and compared between two timeframes in two groups, respectively. Moreover, the receiver operating characteristics (ROC) statistical analysis was used to assess the above parameters.

Results

We divided 33 patients into two groups: 22 in the CR group and 11 in the non-CR group. During the mid-CRT phase in the CR group, both K^trans and Kep rapidly decreased, while only Kep decreased in the non-CR group. The pre-K^trans and pre-Kep in the CR group were substantially higher compared to the non-CR group. Moreover, the rK^trans was also apparently observed as higher at pre-CRT in the CR group compared to the non-CR group. The ROC analysis demonstrated that the pre-K^trans could be the best parameter to evaluate the treatment performance (AUC = 0.74).

Conclusion

Pre-K^trans could be a promising parameter to forecast how patients with locally advanced esophageal cancer will respond to CRT.

Impact of Lipid Peroxidation on the Response of Cell Membranes to High-Speed Equibiaxial Stretching: A Computational Study

The difference between diseased and healthy cellular membranes in response to mechanical stresses is crucial for biology, as well as in the development of medical devices. However, the biomolecular mechanisms by which mechanical stresses interact with diseased cellular components remain largely unknown. In this work, we focus on the response of diseased cellular membranes with lipid peroxidation to high-speed tensile loadings. We find that the critical areal strain (ξ_c, when the pore forms) is highly sensitive to lipid peroxidation. For example, ξ_c of a fully oxidized bilayer is only 64 and 69% of the nonoxidized one at the stretching speed of 0.1 and 0.6 m/s, respectively. ξ_c decreases with the increase in the oxidized lipid ratio, regardless of the speeds. Also, the critical rupture tension of membranes exhibits a similar change. It is obvious that the oxidized membranes are more easily damaged than normal ones by high-speed stretching, which coincides with experimental findings. The reason is that peroxidation introduces a polar group to the tail of lipids, increases the hydrophilicity of tails, and warps the tails to the membrane-water interface, which causes loose accumulation and disorder of lipid tails. This can be deduced from the variation in the area per lipid and order parameter. In addition, the lowering stretching modulus and line tension of membranes (i.e., softening) after lipid peroxidation is also a significant factor. We reveal the difference between the peroxidized (diseased) and normal membrane in response to high-speed stretching, give the ξ_c value in the pore formation of membranes and analyze the influence of the stretching speed, peroxidation ratio, and molecular structure of phospholipids. We hope that the molecular-level information will be useful for the development of biological and medical devices in the future.

[Clinical characteristics of children infected with different subtypes/genotypes of human respiratory syncytial virus in Beijing from 2009 to 2017]

Objective: To explore the different clinical characteristics of children infected with different subtype/genotype of human respiratory syncytial virus (HRSV) in Beijing. Methods: Respiratory specimens for positive HRSV were randomly collected from children with acute respiratory tract infection (ARTI) in the epidemic season of HRSV from November of each year to January of the next year during 2009 and 2017. G genes of HRSV were amplified and sequenced for subtyping and genotyping by bioinformatics analysis. Clinical data were collected and analyzed. Results: Out of 590 children, 376 (63.7%) with subtype A, and 214 (36.3) with subtype B. The annual dominant subtypes of HRSV from 2009 to 2017 were B-A-A-B-AB-A-A-B-A, respectively, whilst a total of 10 genotypes were detected with 95.8% assigned to genotype ON1 and NA1 of subtype A, and genotype BA9 of subtype B. Children infected with subtype B (96 cases, 44.9%) were more likely aged 0-3 month old than those with subtype A (118 cases, 31.4%) (P=0.001), and more likely to be admitted to Intensive Care Unit(ICU) ((124 cases, 57.9%) than those with subtype A (172 cases, 45.7%)) (P=0.005). Statistical significance were shown among children infected with genotype ON1, NA1 or BA9, in the possibility of infection in children aged 0-3 month (P=0.003), proportion of admission into ICU (P=0.007), length of stay in hospital (P=0.001), and clinical outcome (P=0.001), respectively. Conclusion: Children infected with different subtype or genotype of HRSV have different clinical characteristics, which stresses the important role of the monitoring HRSV subtypes and genotypes among children.

Ultra-low-dose estradiol and dydrogesterone: a phase III study for vasomotor symptoms in China

OBJECTIVE

This study aimed to evaluate the efficacy and safety of ultra-low-dose estradiol plus dydrogesterone for vasomotor symptoms in postmenopausal women in China (trial registration CTR20160689).

METHODS

A total of 332 patients were randomized to continuous combined estradiol 0.5 mg + dydrogesterone 2.5 mg or placebo for 12 weeks. The primary efficacy endpoint was change in the number of hot flushes per day from baseline to end of treatment. Secondary efficacy endpoints included change in the number of moderate-to-severe hot flushes per day, menopausal symptoms from baseline and quality of life.

RESULTS

Between baseline and end of treatment, change in the mean number of hot flushes per day was -5.9 (95% confidence interval [CI] - 6.6, -5.2) with estradiol + dydrogesterone and -4.5 (95% CI -5.1, -3.8) with placebo, with a mean difference of -1.4 hot flushes per day (95% CI -2.2, -0.7; p < 0.001). Significant differences in favor of estradiol + dydrogesterone were also observed in several secondary efficacy endpoints. The study treatment was well tolerated.

CONCLUSION

Continuous combined estradiol 0.5 mg + dydrogesterone 2.5 mg reduced hot flushes in postmenopausal women in China. This ultra-low-dose regimen provides an additional option for women experiencing the vasomotor symptoms of menopause. These data are consistent with previous results in other populations.

[Incidence and risk factors of anastomotic leak after transanal total mesorectal excision in China: a retrospective analysis based on national database]

Objective: Transanal total mesorectal excision (taTME) was a very hot topic in the first few years since its appearance, but now more introspections and controversies on this procedure have emerged. One of the reasons why the Norwegian Ministry of Health stopped taTME was the high incidence of postoperative anastomotic leak. In current study, the incidence and risk factors of anastomotic leak after taTME were analyzed based on the data registered in the Chinese taTME Registry Collaborative (CTRC). Methods: A case-control study was carried out. Between November 15, 2017 and December 31, 2020, clinical data of 1668 patients undergoing taTME procedure registered in the CTRC database from 43 domestic centers were collected retrospectively. After excluding 98 cases without anastomosis and 109 cases without complete postoperative complication data, 1461 patients were finally enrolled for analysis. There were 1036 males (70.9%) and 425 females (29.1%) with mean age of (58.2±15.6) years and mean body mass index of (23.6±3.8) kg/m(2). Anastomotic leak was diagnosed and classified according to the International Study Group of Rectal Cancer (ISREC) criteria. The risk factors associated with postoperative anastomotic leak cases were analyzed. The impact of the cumulative number of taTME surgeries in a single center on the incidence of anastomotic leak was evaluated. As for those centers with the number of taTME surgery ≥ 40 cases, incidence of anastomic leak between 20 cases of taTME surgery in the early and later phases was compared. Results: Of 1461 patients undergoing taTME, 103(7.0%) developed anastomotic leak, including 71 (68.9%) males and 32 (31.1%) females with mean age of (59.0±13.9) years and mean body mass index of (24.5±5.7) kg/m(2). The mean distance between anastomosis site and anal verge was (2.6±1.4) cm. Thirty-nine cases (37.9%) were classified as ISREC grade A, 30 cases (29.1%) as grade B and 34 cases (33.0%) as grade C. Anastomotic leak occurred in 89 cases (7.0%,89/1263) in the laparoscopic taTME group and 14 cases (7.1%, 14/198) in the pure taTME group. Multivariate analysis showed that hand-sewn anastomosis (P=0.004) and the absence of defunctioning stoma (P=0.013) were independently associated with anastomotic leak after taTME. In the 16 centers (37.2%) which performed ≥ 30 taTME surgeries with cumulative number of 1317 taTME surgeries, 86 cases developed anastomotic leak (6.5%, 86/1317). And in the 27 centers which performed less than 30 taTME surgeries with cumulative number of 144 taTME surgeries, 17 cases developed anastomotic leak (11.8%, 17/144). There was significant difference between two kinds of center (χ(2)=5.513, P=0.019). Thirteen centers performed ≥ 40 taTME surgeries. In the early phase (the first 20 cases in each center), 29 cases (11.2%, 29/260) developed anastomotic leak, and in the later phase, 12 cases (4.6%, 12/260) developed anastomotic leak. The difference between the early phase and the later phase was statistically significant (χ(2)=7.652, P=0.006). Conclusion: The incidence of anastomotic leak after taTME may be reduced by using stapler and defunctioning stoma, or by accumulating experience.

Impact of Shock-Induced Cavitation Bubble Collapse on the Damage of Cell Membranes with Different Lipid Peroxidation Levels

Although the interaction mechanism between shock waves and cells is critical for advancing the medical applications of shock waves, we still have little understanding about it. This work aims to study the response of diseased cells subjected to lipid peroxidation to the nanojet from shock wave-induced bubble collapse by using the coarse-grained molecular dynamics simulation. Factors considered in the simulations include the shock velocity (up), movement time of piston (τp), bubble size (R), and peroxidation level of membranes. Here, we mainly focus on the role of peroxidation levels, that is, the degree (%) and the distribution of oxidized lipids in membranes. The results indicate that the shock damage threshold (up at which the pore in membranes is formed) of peroxidation membranes is less than that of normal membranes and decreases with the peroxidation degree. Importantly, the distribution of oxidized lipids has more effect on the damage threshold than the peroxidation degree. The threshold of membrane with 33% localized oxidized lipids is lower than that of membrane with 50% average oxidized lipids. The results can be explained by the stretching modulus (κs) and bending modulus (κb) of cell membranes. For example, the κb value (4.3 × 10-20 J) of 100% peroxidation membrane is about half of that (8.4 × 10-20 J) of a membrane without peroxidation. A lower modulus means high deformation under the same impact. Further analysis shows that peroxidation introduces a polar hydrophobic group to the tail of phospholipids that increases the hydrophilicity of tails and warps the tail of phospholipids toward the membrane-water interface, resulting in looser accumulation. This can be confirmed by the increased average phospholipid area with peroxidation levels. Indeed, most of the pores formed during the shock can heal. However, the permeation of water molecules across the healing membrane still increased. All these membrane-level information obtained from this study will be useful for improving the biomedical applications of shock waves.

[Diagnosis and treatment of Chlamydia psittaci pneumonia: experiences of 8 cases]

Objective: In order to improve the understanding and clinical treatment of Chlamydia psittaci pneumonia, we analyzed the clinical manifestations, laboratory test results and imaging features of 8 patients. Methods: We collected the clinical data of 8 patients with Chlamydia psittaci pneumonia diagnosed by metagenomic next-generation-sequencing (mNGS) from November 2018 to February 2020, including clinical features, chest CT scan, pathological features and antibiotic use. Results: A total of one male and 7 females, aged from 45 to 85 years(median 62 years), were included in this study. All the patients had high fever, cough and most had expectoration (6/8). The leukocyte count and PCT level were mostly normal (7/8). However, we observed decreased lymphocyte count(5/8), elevated C-reactive protein in all patients, and increased ESR in most patients (7/8). The chest CT of all the patients showed large patchy consolidation, with one case having pleural effusion. The pathological manifestations were nonspecific, showing infiltration of inflammatory cells and exudation. Moxifloxacin and/or doxycycline were administered after diagnosis, and the course of treatment lasted from 14 to 21 days.Chest CT showed absorption of lesions following treatment Conclusions: Chlamydia psittaci pneumonia showed certain characteristics, including high fever with pulmonary patchy consolidation, and normal white blood cell count. Molecular diagnostic methods such as mNGS could lead to rapid diagnosis and treatment which can shorten the course of hospitalization and thus improve prognosis.

[Risk factors and clinical prognosis analysis of carbapenem-resistant Enterobacterales bacteria nosocomial infection]

Objective: To explore the risk factors for carbapenem-resistant Enterobacterales (CRE) infection and death. Methods: A case-control analysis of 482 inpatients in 18 secondary or tertiary hospitals in Beijing in 2018 was conducted. Patients infected by CRE were selected as the case group (n=247), and infected by carbapenem susceptible Enterobacterales (CSE) as the control group (n=235). The risk factors and clinical prognosis of CRE infection were analyzed by single factor analysis and multivariate logistic regression analysis. Results: CRE were resistant to most antimicrobials, but were highly sensitive to colistin and tigecycline, with sensitivity of 94.0% and 99.5%, respectively. Multivariate analysis showed that prior 30-day tracheal intubation (OR=2.607, 95%CI: 1.655-4.108, P<0.001), empirical treatment using third or fourth generation cephalosporins (OR=2.339, 95%CI: 1.438-3.803, P=0.001), carbapenems (OR=2.468, 95%CI: 1.610-3.782, P<0.001) and quinolones (OR=2.042, 95%CI: 1.268-3.289, P=0.003) were independent risk factors for CRE infection. Mechanical ventilation (OR=3.390, 95%CI: 1.454-7.904, P=0.005), heart failure (OR=4.679, 95%CI: 1.975-11.083, P<0.001), moderate or severe liver disease (OR=3.057, 95%CI: 1.061-8.806, P=0.038), prior 30-day quinolones exposure (OR=2.882, 95%CI: 1.241-6.691, P=0.014) and septic shock (OR=7.772, 95%CI: 3.505-17.233, P<0.001) were independent risk factors for death after CRE infection. Conclusions: Reducing the use of antimicrobials and invasive procedures such as prior 30-day tracheal intubation may reduce the probability of CRE infection. Grading the severity of the underlying disease in patients with CRE infection, as well as predicting and preventing the occurrence of septic shock will help reduce the risk of death.

POS0776 CORRELATION OF PERIPHERAL CD4+GRANZB+CTLS WITH DISEASE SEVERITY IN PATIENTS WITH PRIMARY SJÖGREN’S SYNDROME

Background:

Sjögren’s syndrome (SS) is a chronic autoimmune disorder. The major histopathologic lesion of it is a focal lymphocytic infiltrate around ductal and acinar epithelial cells, which include a majority of CD4+T. Several studies have shown that the epithelial cells in SS present diverse phenomena, such as MHC class II overexpression. CD4+T cells with cytotoxic activity (CD4 CTL) have been detected in various immune responses. They are characterized by their ability to secrete perforin and granzyme B to kill the target cells in an MHC class II-restricted fashion.

Objectives:

So this study was to investigate the correlation of peripheral CD4+GranzB+CTLs with disease severity and organ involvement in patients with primary Sjögren’s syndrome.

Methods:

We recruited 116 pSS patients and 46 healthy controls using flow cytometry to examine proportion of CD4+GranzB+CTLs in their peripheral blood, and immunofluorescence to test the expression of CD4+GranzB+CTLs in labial gland. The correlations of CD4+GranzB+CTLs and the relevant clinical data were analyzed.

Results:

We analyzed the percentage of CD4+GranzB+cytotoxic T cells in peripheral blood mononuclear cells (PBMCs) by flow cytometry. Frequency of peripheral CD4+GranzB+CTLs were measured in 116 patients with pSS and 46 healthy controls matched for age and sex. The percentage of CD4+GranzB+CTLs were significantly up-regulated in pSS patients than healthy controls (7.1%±4.9% vs 3.1%±1.9%, p <0.0001) and positive correlation with ESSDAI in pSS patients(r = 0.6332, p<0.001). The percentage of CD4+GranzB+CTLs were markedly higher in pSS patients with extraglandular manifestations. Moreover, CD4+GranzB+CTLs were observed in the lymphocytic foci and periductal areas of the LSGs and were elevated with increased foci index (FI). After excluding the other risk factors associated with pSS, CD4+GranzB+CTLs were still related to ESSDIA and extraglandular manifestations independently(p<0.05). ROC curve analysis indicated that the area under the curve (AUC) of CD4+GranzB+CTLs was 0.796 to predict the activity of pSS, and 0.851 to presume extraglandular manifestations. The best diagnostic cut-off point was 4.865 for pSS patients.

Conclusion:

In this study, We provide new evidence indicating involvement of CD4+GranzB+CTLs over activation in the disease pathophysiology of pSS, which may serve as a new biomarker to evaluate the activity and severity of pSS.

References:

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Table 1.

Multivariate analysis of CD4+GranzB+CTLs influenced by pSS-related factors

regression coefficientstandard errort-statisticsp value95%CICD8+GranzB+CTLs(%)0.1440.0334.3346.9E-50.077, 0.211ESSDAI0.2560.1222.0950.0410.011, 0.502extraglandular manifestations2.6121.2682.0590.0450.065, 5.158Figure 1.

Receiver operating characteristic (ROC) curve of the frequency of CD4+GranzB+CTLs to predict ESSDAI and extraglandular manifestations response

Disclosure of Interests:

None declared

The value of 18F-FDG PET/CT imaging combined with detection of CA125 and HE4 in the diagnosis of recurrence and metastasis of ovarian cancer

OBJECTIVE

To explore the clinical application value of 18F-fluorodeoxyglucose (18F-FDG) PET/CT imaging combined with detection of serum tumor molecular markers (carbohydrate antigen 125 (CA 125) and human epididymis protein 4 (HE4)) in the diagnosis of recurrence and metastasis of ovarian cancer.

PATIENTS AND METHODS

Clinical data about 18F-FDG PET/CT imaging and serum CA125 and HE4 of 69 ovarian cancer patients after the first cytoreductive surgery and chemotherapy were retrospectively analyzed, and the clinical application value of 18F-FDG PET/CT imaging combined with detection of CA125 and HE4 in the diagnosis of recurrence and metastasis of ovarian cancer was evaluated.

RESULTS

The 18F-FDG PET/CT images of recurrence and metastasis of ovarian cancer showed hypermetabolism. The sensitivity, specificity, accuracy, predictive positive value, and predictive negative value of 18F-FDG PET/CT imaging for the diagnosis of recurrence and metastasis of ovarian cancer were 90.74%, 86.67%, 89.86%, 96.08%, and 72.22%, respectively; those of CA125 for the diagnosis of them were 77.78%, 86.67%, 79.71%, 95.45% and 52.00%, respectively, and those of HE4 for the diagnosis of them were 70.37%, 93.33%, 76.84%, 97.44%, and 48.39% respectively. In addition, the sensitivity and specificity of 18F-FDG PET/CT combined with detection of serum CA125 and HE4 for the diagnosis were 100.00% and 100.00%, respectively, significantly higher than those of separate 18F-FDG PET/CT imaging, detection of serum CA125, and detection of serum HE4 (c2 = 5.243, 13.500, 18.783, p = 0.022, 0.000, 0.000; c2 = 4.000, 8.525, 9.864, p = 0.046, 0.004, 0.002), and the accuracy of the combination use of them was 95.65%, also significantly higher than that of separate CA125 and HE4 (c2 = 8.118, 10.315, p = 0.004, 0.001, both p < 0.01). Furthermore, the maximum standardized uptake value (SUVmax) of 18F-FDG PET/CT imaging for recurrence and metastasis of ovarian cancer focuses was significantly positively correlated with serum CA125 and HE4 levels (r = 0.596, p = 0.000; r = 0.431, p = 0.002), and the serum CA125 level was also significantly positively correlated with serum HE4 level in patients with recurrent or metastasized ovarian cancer (r = 0.198, p = 0.043,).

CONCLUSIONS

18F-FDG PET/CT imaging combined with detection of serum CA125 and HE4 can significantly improve the diagnostic efficiency to recurrence and metastasis of ovarian cancer and is conducive to the early diagnosis of the recurrence and metastasis, which provides a basis for further clinical intervention.

Continuous and discontinuous transitions in the depinning of two-dimensional dusty plasmas on a one-dimensional periodic substrate

Langevin dynamical simulations are performed to study the depinning dynamics of two-dimensional dusty plasmas on a one-dimensional periodic substrate. From the diagnostics of the sixfold coordinated particles P_{6} and the collective drift velocity V_{x}, three different states appear, which are the pinning, disordered plastic flow, and moving ordered states. It is found that the depth of the substrate is able to modulate the properties of the depinning phase transition, based on the results of P_{6} and V_{x}, as well as the observation of hysteresis of V_{x} while increasing and decreasing the driving force monotonically. When the depth of the substrate is shallow, there are two continuous phase transitions. When the potential well depth slightly increases, the phase transition from the pinned to the disordered plastic flow states is continuous; however, the phase transition from the disordered plastic flow to the moving ordered states is discontinuous. When the substrate is even deeper, the phase transition from the pinned to the disordered plastic flow states changes to discontinuous. When the depth of the substrate further increases, as the driving force increases, the pinned state changes to the moving ordered state directly, so that the disordered plastic flow state disappears completely.

[Influence of comprehensive incubational measures on the perioperative treatment of extensively burned patients who underwent escharectomy and skin grafting]

Objective: To explore the influence of standardized and comprehensive incubational measures on perioperative treatment of extensively burned patients who underwent escharectomy and skin grafting. Methods: From January 2017 to November 2018, 50 patients with extensive burn who underwent escharectomy and skin grafting in the First Affiliated Hospital of Air Force Medical University and met the inclusion criteria of this study, were recruited in this retrospective cohort study. According to the incubational measures at that time, 20 patients (14 males and 6 females, aged (33.5±5.2) years) who received routine incubation during the perioperative period from January to October 2017 were set as routine incubation group, and 30 patients (23 males and 7 females, aged (35.8±1.4) years) who received standardized comprehensive incubational measures during the perioperative period from November 2017 to November 2018 were set as comprehensive incubation group. Their body temperature was controlled mainly in 4 stages: preoperative preparation and transfer from intensive care unit (ICU) to operating room, preoperative preparation in operating room, intraoperative operating room management, as well as postoperative transfer from operating room to ICU. The initial body temperature in operating room and intraoperative hypothermia duration, intraoperative blood loss, postoperative recovery time, postoperative chill, blister, and ulcer, and wound healing rate on post operation day (POD) 10 were recorded and calculated. Data were statistically analyzed with two independent samples t test and chi-square test. Results: (1) The initial body temperature in operating room of patients in comprehensive incubation group was (36.3±0.4) ℃, which was significantly higher than (35.6±0.4)℃ in routine incubation group, t=6.658, P<0.01; the intraoperative duration of hypothermia was (205±38) min, which was significantly shorter than (234±42) min in routine incubation group, t=2.564, P<0.05. (2) The intraoperative blood loss of patients in comprehensive incubation group was (323±114) mL, which was significantly less than (490±162) mL in routine incubation group, t=4.272, P<0.01; the postoperative recovery time was (36±8) min, which was significantly shorter than (49±17) min in routine incubation group, t=3.229, P<0.01. (3) The incidence of postoperative chill of patients in comprehensive incubation group was significantly lower than that in routine incubation group (χ(2)=28.626, P<0.01). The incidences of postoperative blister and ulcer of patients between the 2 groups were close. (4) On POD 10, the wound healing rate of patients in comprehensive incubation group was (78.08±0.06)%, which was significantly higher than (71.03±0.08)% in routine incubation group, t=3.694, P<0.01. Conclusions: The standardized and comprehensive incubational measures can effectively improve the initial body temperature of patients entering the operating room, shorten the intraoperative duration of hypothermia, reduce the amount of blood loss and postoperative complications, as well as shorten the postoperative recovery time, thus improve the wound healing rate.

First Measurement of Differential Charged Current Quasielasticlike ν_{μ}-Argon Scattering Cross Sections with the MicroBooNE Detector

We report on the first measurement of flux-integrated single differential cross sections for charged-current (CC) muon neutrino (ν_{μ}) scattering on argon with a muon and a proton in the final state, ^{40}Ar (ν_{μ},μp)X. The measurement was carried out using the Booster Neutrino Beam at Fermi National Accelerator Laboratory and the MicroBooNE liquid argon time projection chamber detector with an exposure of 4.59×10^{19} protons on target. Events are selected to enhance the contribution of CC quasielastic (CCQE) interactions. The data are reported in terms of a total cross section as well as single differential cross sections in final state muon and proton kinematics. We measure the integrated per-nucleus CCQE-like cross section (i.e., for interactions leading to a muon, one proton, and no pions above detection threshold) of (4.93±0.76_{stat}±1.29_{sys})×10^{-38}  cm^{2}, in good agreement with theoretical calculations. The single differential cross sections are also in overall good agreement with theoretical predictions, except at very forward muon scattering angles that correspond to low-momentum-transfer events.

Application of Artificial Intelligence in Dentistry

Artificial intelligence (AI) is a technology that utilizes machines to mimic intelligent human behavior. To appreciate human-technology interaction in the clinical setting, augmented intelligence has been proposed as a cognitive extension of AI in health care, emphasizing its assistive and supplementary role to medical professionals. While truly autonomous medical robotic systems are still beyond reach, the virtual component of AI, known as software-type algorithms, is the main component used in dentistry. Because of their powerful capabilities in data analysis, these virtual algorithms are expected to improve the accuracy and efficacy of dental diagnosis, provide visualized anatomic guidance for treatment, simulate and evaluate prospective results, and project the occurrence and prognosis of oral diseases. Potential obstacles in contemporary algorithms that prevent routine implementation of AI include the lack of data curation, sharing, and readability; the inability to illustrate the inner decision-making process; the insufficient power of classical computing; and the neglect of ethical principles in the design of AI frameworks. It is necessary to maintain a proactive attitude toward AI to ensure its affirmative development and promote human-technology rapport to revolutionize dental practice. The present review outlines the progress and potential dental applications of AI in medical-aided diagnosis, treatment, and disease prediction and discusses their data limitations, interpretability, computing power, and ethical considerations, as well as their impact on dentists, with the objective of creating a backdrop for future research in this rapidly expanding arena.

A Density Functional Theory Study toward Ring-Opening Reaction Mechanisms of 2,4,6-Trinitrotoluene's Meisenheimer Complex for the Biodegradation of Old Yellow Enzyme Flavoprotein Reductase

The subsequent degradation pathway of the dihydride-Meisenheimer complex (2H^--TNT), which is the metabolite of 2,4,6-trinitrotoluene (TNT) by old yellow enzyme flavoprotein reductases of yeast and bacteria, was investigated computationally at the SMD/TPSSH/6-311+G(d,p) level of theory. Combining the experimentally detected products, a series of protonation, addition, substitution (dearomatization), and ring-opening reaction processes from 2H^--TNT to alkanes were proposed. By analyzing reaction free energies, we determined that the protonation is more advantageous thermodynamically than the dimerization reaction. In the ring-opening reaction of naphthenic products, the water molecule-mediated proton transfer mechanism plays a key role. The corresponding activation energy barrier is 37.7 kcal·mol^-1, which implies the difficulty of this reaction. Based on our calculations, we gave an optimum pathway for TNT mineralization. Our conclusions agree qualitatively with available experimental results. The details on transition states, intermediates, and free energy surfaces for all proposed reactions are given and make up for a lack of experimental knowledge.

MOTS-c improves osteoporosis by promoting the synthesis of type I collagen in osteoblasts via TGF-β/SMAD signaling pathway

OBJECTIVE

To investigate whether MOTS-c can regulate the synthesis of type I collagen in osteoblasts by regulating TGF-β/SMAD pathway, thereby improving osteoporosis.

MATERIALS AND METHODS

Viability of hFOB1.19 cells treated with MOTS-c was detected by CCK-8 assay. The mRNA and protein levels of TGF-β, SMAD7, COL1A1 and COL1A2 in hFOB1.19 cells were detected by quantitative Real-time polymerase chain reaction (qRT-PCR) and Western blot, respectively. We then changed expressions of TGF-β and SMAD7 by plasmids transfection to detect levels of COL1A1 and COL1A2 in hFOB1.19 cells by qRT-PCR and Western blot, respectively.

RESULTS

Cell viability was significantly increased after treatment of 1.0 μM MOTS-c for 24 h or 0.5 μM MOTS-c for 48 h in a time-dependent manner. The mRNA and protein expressions of TGF-β, SMAD7, COL1A1 and COL1A2 in hFOB1.19 cells were dependent on the concentration of MOTS-c. In addition, MOTS-c increased the expressions of COL1A1 and COL1A2, which were partially reversed by knockdown of TGF-β or SMAD7.

CONCLUSIONS

MOTS-c could promote osteoblasts to synthesize type I collagen via TGF-β/SMAD pathway.

First Measurement of Inclusive Muon Neutrino Charged Current Differential Cross Sections on Argon at E_{ν}∼0.8 GeV with the MicroBooNE Detector

We report the first measurement of the double-differential and total muon neutrino charged current inclusive cross sections on argon at a mean neutrino energy of 0.8 GeV. Data were collected using the MicroBooNE liquid argon time projection chamber located in the Fermilab Booster neutrino beam and correspond to 1.6×10^{20} protons on target of exposure. The measured differential cross sections are presented as a function of muon momentum, using multiple Coulomb scattering as a momentum measurement technique, and the muon angle with respect to the beam direction. We compare the measured cross sections to multiple neutrino event generators and find better agreement with those containing more complete treatment of quasielastic scattering processes at low Q^{2}. The total flux integrated cross section is measured to be 0.693±0.010(stat)±0.165(syst)×10^{-38}  cm^{2}.

Liquid-like behaviours of metallic glassy nanoparticles at room temperature

Direct atomic-scale observations and measurements on dynamics of amorphous metallic nanoparticles (a-NPs) are challenging owing to the insufficient consciousness to their striking characterizations and the difficulties in technological approaches. In this study, we observe coalescence process of the a-NPs at atomic scale. We measure the viscosity of the a-NPs through the particles coalescence by in situ method. We find that the a-NPs have fast dynamics, and the viscosity of the a-NPs exhibits a power law relationship with size of the a-NPs. The a-NPs with sizes smaller than 3 nm are in a supercooled liquid state and exhibit liquid-like behaviours with a decreased viscosity by four orders of magnitude lower than that of bulk glasses. These results reveal the intrinsic flow characteristics of glasses in low demension, and pave a way to understand the liquid-like behaviours of low dimension glass, and are also of key interest to develop size-controlled nanodevices.

Nanoscale materials often exhibit size-dependent behaviour. Here, the authors use electron microscopy to quantitatively study the size-related dynamics of amorphous metallic nanoparticles, finding that particles below a critical size are in a supercooled liquid state at room temperature, with a viscosity much lower than that of bulk glasses.

Clinical and radiographic characterization of primary seminomas and nonseminomatous germ cell tumors

Background

Primary malignant mediastinal germ cell tumors (PMMGCTs) including seminomas and nonseminomatous germ cell tumors (NSGCTs) are rare, and sometimes the diagnosis is very difficult.

Purpose

The purpose of this study is to compare the clinical characteristics, biomarkers, and imaging findings of seminomas and NSGCTs and to determine whether these features could help distinguish these two types of PMMGCT.

Material and Methods

A retrospective study of 24 male patients with histopathologically proven PMMGCT was performed. We collected the information of computed tomography (CT) (the scan area ranged from the apex of lung to the costophrenic angles) and magnetic resonance imaging blood test and histology characteristics of these patients.

Results

Twelve of 24 cases were confirmed to be seminomas, whereas the other 12 cases were NSGCTs. Alfa-fetoprotein (AFP) was found to be elevated in all patients with NSGCT, whereas none of the patients with seminomas had elevated AFP level. Beta-human chorionic gonadotropin (β-HCG) level was elevated in all the patients with seminomas (seven/seven), whereas in NSGCT only two of seven patients had elevated β-HCG. Lactate dehydrogenase level was increased in five of the nine patients with seminomas, as well as in the eight patients with NSGCT. CT imaging revealed that 12 masses from the seminoma group were homogeneous, soft tissue opacity and showed minimal contrast enhancement. On the contrary, all 12 NSGCT cases showed cystic and solid masses; on contrast-enhanced CT, heterogeneous enhancement was found on the capsule of the tumor, septum, and solid masses.

Conclusion

Seminomas and NSGCT showed different profiles of tumor biomarkers and radiographic features. Evidence from serum test, histopathological analysis, and imaging should be combined to ensure the accurate diagnosis of these two types of PMMGCT.

Abstract P6-01-02: Machine learning-based structural analysis and oxygen saturation measurement of tumor-associated vessels in breast cancer using a photoacoustic tomography system

Introduction

Breast cancer induces angiogenesis, one of the primary factors responsible for tumor progression. Therefore, the ability to visualize angiogenesis at a higher resolution is crucial. Photoacoustic tomography is a noninvasive method of visualizing angiogenesis involving light absorption and ultrasonic wave emission. If the irradiation light wavelength is adjusted for hemoglobin, vascular imaging is possible. Furthermore, using two wavelengths for oxidized and reduced hemoglobin, “S-factor,” can be calculated, which nearly corresponds to oxygen saturation. Therefore, photoacoustic imaging allows the assessment of breast lesions from vascular structural and functional viewpoints.

Objectives

This study aimed to demonstrate the possible utility of photoacoustic tomography for clinical application focusing on the morphologic features and oxygen saturation status of breast tumor-related vessels.

Methods

For the morphological analysis, we applied a machine learning-based method for automatic vessel extraction, and for the functional analysis we evaluated hemoglobin oxygen saturation calculating signals obtained at two wavelengths. In our system, a 3D ultrasound image was simultaneously acquired as a volume image of a tumor, which helped analyze the positional relationship between the vessels and the tumor.

Results

On morphological analysis, the fine structure of tumor-related vessels was rendered in high resolution. In our system, the blood vessels branched toward the tumor 2-3 more times more frequently than observed on contrast-enhanced MRI, illustrating a finer level of blood vessels near the tumor on our system than on MRI. Next, we analyzed the six morphologic features of vessels (radius, volume, curvature, contraction, maximum angle and vessel branch number) that are associated with the pathologic condition in neuroscience. We determined that the feature distribution of vessels located close to the tumor differed from that located away from the tumor. For example, vessels near the tumor had higher curvature, which means they are more tortuous than healthy vessels. The difference in the distribution of all six features was statistically significant on the Kolmogorov-Smirnov test.

On functional analysis, S-factor measurement of the healthy human breast demonstrated clearly demarcated arteries and veins. The S-factor of any artery was nearly 100%, while that of the veins inside the breast cancer tended to be a little higher (approximately 5%) compared to that in the healthy part. This tendency of veins was not recognized in benign tumors. This could show arteriovenous shunt in cancer microenvironment. We found low saturation signals emerging in the tumor tissue following bevacizumab-containing chemotherapy, indicating the possibility that our system reveals microenvironment changes.

Discussion

If our system can identify the structure or oxygen saturation characteristics unique to tumor-associated vasculature, it could contribute to the improved accuracy of breast cancer diagnosis and allow the observation of tumor vessel normalization because of the drug treatment. An earlier grasp of the therapeutic effect could lead to the provision of individualized medicine.

Citation Format: Matsumoto Y, Gu L, Bise R, Asao Y, Sekiguchi H, Yoshikawa A, Ishii T, Takada M, Kataoka M, Sakurai T, Yagi T, Sato I, Togashi K, Shiina T, Toi M. Machine learning-based structural analysis and oxygen saturation measurement of tumor-associated vessels in breast cancer using a photoacoustic tomography system [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-01-02.