Clonostachys have contributed to the biological control of plant fungal disease and nematodes. The Clonostachys fungi strains were isolated from Ophiocordyceps highlandensis, Ophiocordycepsnigrolla and soil, which identified as Clonostachyscompactiuscula, Clonostachysrogersoniana, Clonostachyssolani and Clonostachys sp. To explore the evolutionary relationship between the mentioned species, the mitochondrial genomes of four Clonostachys species were sequenced and assembled. The four mitogenomes consisted of complete circular DNA molecules, with the total sizes ranging from 27,410 bp to 42,075 bp. The GC contents, GC skews and AT skews of the mitogenomes varied considerably. Mitogenomic synteny analysis indicated that these mitogenomes underwent gene rearrangements. Among the 15 protein-coding genes within the mitogenomes, the nad4L gene exhibited the least genetic distance, demonstrating a high degree of conservation. The selection pressure analysis of these 15 PCGs were all below 1, indicating that PCGs were subject to purifying selection. Based on protein-coding gene calculation of the significantly supported topologies, the four Clonostachys species were divided into a group in the phylogenetic tree. The results supplemented the database of mitogenomes in Hypocreales order, which might be a useful research tool to conduct a phylogenetic analysis of Clonostachys. Additionally, the suitable molecular marker was significant to study phylogenetic relationships in the Bionectriaceae family.The mycoparasite fungi of  Clonostachys  refers to an asexual morph-typified genus formed by the type species C. araucaria in 1939, which is now recognized as a synonym of C. rosea [Clonostachys species inhabit soil, fungi and dying trees or rotting leaves in tropical and temperate regions [http://www.indexfungorum.org, accessed on 10 December 2020) [Clonostachys have been commercially developed for the biological control of plant pathogens. C. rosea is a generally well-known species of the genus and can potentially contribute to the biological control of plant fungal disease and nematodes [ regions ; minorit regions . The gener 2020) ,6,7. Somematodes .Clonostachys genus are transferred from another genus, such as Bionectria, Nectria and Gliocladium genus. However, this genus taxonomic position, compared with another family in the Hypocreales order, is often debated [Bionectria and Clonostachys, 43 species were reported in this genus [Clonostachys genus [Clonostachys species [Clonostachys species. Accordingly, it is imperative to acquire more useful data and use advanced techniques to illustrate the taxonomic status and characteristics of this genus.Most members of  debated . Since Sys genus ,6. James species . A lack Clonostachys rosea has been the only reported mitogenome of Clonostachys to date [Clonostachys species. Therefore, it is necessary to complement the mitogenome of the Clonostachys species.The mitochondrion, a circle organelle exists in almost eukaryotes species cell, which usually provides a source of chemical energy through oxidative phosphorylation . The mit to date . The lacClonostachys species were accurately identified, i.e., Clonostachys compactiuscula, Clonostachys rogersoniana, Clonostachys solani and Clonostachys sp. This was used to characterize morphologies under a microscopy and to conduct molecular analyses. The Clonostachys sp. refers to a potential new species of Clonostachys genus. Further, the four complete mitogenomes were sequenced, assembled and annotated. In order to identify the phylogenetic relationship and sequence characteristics of Clonostachys genus, these four mitogenomes’ gene contents, gene orders and codon usage were analyzed comparatively. The structural differences in the mitochondrial genomes in this genus were analyzed. The results achieved in this study not only complement new molecular information about the Bionectriaceae family in the Hypocreales order, but also provide an understanding of the characteristics and phylogenetic relationships of this class.In this study, four C. compactiuscula, C. rogersoniana and C. solani were compared with the original description [To ensure species accuracy, microscopic morphological characteristics and molecular analyses were first used to identify the abovementioned species. Micromorphological characteristics with asexual morphs involving cription ,15  database, consisting of 66 fungal sequences, as well as ML analyses and BI analysis, were conducted to verify the presence and positions of the four Clonostachys species. The phylogenetic tree demonstrating that C. rogersoniana, C. compactiuscula and C. solani join the reference sequence come from NCBI and exhibited high support rates. In addition, the Clonostachys sp. was an unknown species based on microscopic morphological and phylogenetic analyses  were identified in the four mitogenomes, in amounts ranging from 1 to 20 in each genome. Except for orf178 of C. solani, located on the reverse strand, all the genes of another three mitogenomes were located on the direct strand.The numbers of PCGs were different in four species: Clonostachys mitogenomes contained overlapping nucleotides sequences ranging from 1 to 3 bp, and each species contained the same gene overlapping region between the adjacent genes nad4L- nad5 (1 bp). The C. compactiuscula mitogenomes identified that largest overlapping nucleotide was 2056 bp, located at neighboring genes rnl and rps3. We identified intergenic nucleotides of 8383 bp, 3807 bp, 8162 bp and 6096 bp from mitogenomes of C. compactiuscula, C. rogersoniana, C. solani and Clonostachys sp. The length of intergenic segments ranged from 1 to 1358 bp. The longest intergenic segments were situated in orf394 and trnR-TCT of C. rogersoniana.The four Clonostachys mitogenomes involved two rRNA genes: the small subunit ribosomal RNA gene (rns) and the large subunit ribosomal RNA gene (rnl). No significant difference was identified in the number of rRNA genes in the four species, and the total length of rRNA genes in the four Clonostachys mitogenomes was altered from 6163 bp to 6400 bp. Besides C. rogersoniana, where 26 tRNA genes were identified in the mitogenomes, 25 tRNA genes were identified in the other three mitogenomes, encoding 20 standard amino acids. Each of the mitogenomes contained three tRNA genes with the identical anticodons for methionine (trnM-CAT), and two tRNAs with different anticodons for arginine (trnR-ACG and trnR-TCT) and serine (trnS-GCT and trnS-TGA). Remarkably, C. rogersoniana mitogenome included four different anticodons for leucine . In another three mitogenomes, C. compactiuscula, C. solani and Clonostachys sp. included two for leucine (trnL-TAA and trnL-TAG). The length of tRNA genes in the four mitogenomes ranged from 71 bp to 86 bp , TTA , ATT , TAT , AAT , AAA , as well as ATA  . The higC.solani, 13 in C.compactiuscula and 2 in Clonostachys sp., except for C. rogersoniana mitogenome; the test used self-comparisons of mitogenomes BLASTn searches , and Clonostachys sp. (2.11%).Fifteen repeat sequences were identified in searches . The lenC. rogersoniana, 15 in C. solani, 6 in C. compactiuscula and 8 in Clonostachys sp.  was highest in nad1, and nad4L had the lowest rate of the 15 core PCGs. The Ka/Ks values indicating that all PCGs were subjected to purifying selection were due to the Ka/Ks values of 15 PCGs, which were <1.Of the 15 core PCGs, nad6 displayed the closest K2P genetic distance among the four mitogenomes, followed by  species . The higClonostachys mitogenomes, showing a close phylogenetic relationship among the mentioned species. Additionally, the order of 24 tRNAs shared by the four Clonostachys species were identical across the four mitogenomes. However, only C. rogersoniana exhibited two additional tRNAL, thereby causing the difference in the gene orders among the four mitogenomes.Gene order and rearrangement in the mitogenome had great significance for biological evolution. The relative positions of two rRNA and fifteen PCGs were highly conserved across the four Clonostachys mitogenomes. The relative positions of regions were highly conserved, and four of the six were detected in these species mitogenomes, while only C. solanni contained whole regions compared to C. rogersoniana, C. compactiuscula andClonostachys sp. However, the size of these homologous regions varied considerably across the four Clonostachys mitogenomes. The widest homologous region was region A in C. compactiuscula and C. solanni, making the mitogenome sequence longer than other mitogenomes. The Clonostachys sp. mitogenome lacked two regions for E and F, which resulted in a shorter mitogenome sequence than other three mitogenomes  were divided into four ogenomes .Clonostachys mitogenomes, as combined in 52 species that represent six families in the Hypocreales order, i.e., Ophiocordycipitaceae, Clavicipitaceae, Hypocreaceae, Cordycipitaceae, Bionectriaceae and Nectriaceae. For both the ML and BI trees, the 52 Hypocreales species could be divided into six major clades, which coincidently classified with different clades and exhibited high confidence . Among the species in Hypocreales order, the Nectriaceae family was located at the foundational position of the integral phylogenomic tree. The clade united at the families of Ophiocordycipitaceae and Clavicipitaceae, and formed a sister cluster with the families of Hypocreaceae and Cordycipitaceae. Furthermore, the Clonostachys species comprised the Bionectriaceae clade and was further subdivided into groups, recovering as (Clonostachys sp. + (C.compactiuscula+ (C. rosea + C. solanni)))  database and existing studies.The phylogenetic analysis employed the nucleotide sequences of 14 common core genes from these four lanni))) . The C. Clonostachys genus were published, which provided more insights into mitogenomes in this genus and supplemented the molecular database in such a classification group.To carry out a good systematic study of this genus, a new potential species was found, and the mitogenomes of four species in https://www.ncbi.nlm.nih.gov/genome/browse#!/organelles/, accessed on 10 December 2020, within the scope of 1140 bp [Rhizoctoniasolani and Hyaloraphidium curvatum, respectively [Ophiocordyceps sinensis was the largest mitogenomic  in the Hypocreales order, containing the most introns [Clonostachys were varied, ranging from 27,410 bp to 42,075 bp. The considerable variation in mitogenome sizes provided a new insight into mitogenome differences at the genus level [C. compactiuscula, C. rogersoniana and C. solani mitogenomics contained two introns, except for Clonostachys sp. In the present paper, Clonostachys sp. mitogenomic was the shortest among all Clonostachys species’ mitogenomics. Additionally, the mitogenome’s size was not always positively related to the number of introns. For example, the length of C. rogersoniana’s mitogenomic was the biggest among the four species due to its adding potential new genes. The GC content of mitogenomics is considered to be affected by the mutation bias, selection and biases of reconstitution-related DNA repair, which were clearly differentiated [Clonostachys species were negative (A less than T), while the other four were positive (T less than A), suggesting that these four species might suffer different selection pressures.As compared with animal and plant mitogenomes, fungal mitogenomes are the largest and most variable length in eukaryotic mitogenomes ,16. Howe 1140 bp  to 258,8 1140 bp . The sizectively ,18. Like introns . Previou introns ,22,23. Ius level . Howeverentiated ,27. Hereentiated , every bentiated . Subsequatp6, atp8, atp9, cob, cox1, cox2, cox3, rps3, nad1, nad2, nad3, nad4, nad4L, nad5 and nad6, were observed in most eukaryotic mitogenomes. The fifteen core genes differed considerably in length, GC content, and evolutionary rates among the mitogenomes of the Clonostachys species. Moreover, the AT and GC skews were varied among species in these core genes, which facilitated the observed genetic differentiation among the mentioned species. Moreover, some independent and unknown functions ORFs were detected in Clonostachys mitogenomes and these genes’ sizes and position varied among the mitogenomes of Clonostachys, indicating that there were still many undiscovered proteins in Clonostachys mitogenomes. Consequently, these ORFs were important factors that contributes to mitogenome differentiation, such as gene rearrangement among Clonostachys species. These results were consistent with previous studies [Since the mitogenome of eukaryotes obtained from ancestral endosymbiotic bacteria, mitogenomes have been considerably differentiated with original nuclear genomes ,30, in w studies .Clonostachys mitogenomes, except for C. rogersoniana. The length of these repeats was ranged from 33 bp to 146 bp. The repeated sequences found in the three mitogenomes might cause variations in gene structure and content, or with contribute to species’ differentiation.Repetitive elements often change the mitochondrial structure in the fungal mitogenome . The chaClonostachys genus. Mitogenomes have many advantages, such as their rapid evolution, few genes, simple structure, maternal inheritance and single copy [cox1, cox2 and cob were often used in some species phylogenetic research, especially in animals [cox1 can be considered as a potential molecular marker for the phylogenetic analysis of fungal species. The results achieved in this study provide a useful tool for phylogenetic analysis of Clonostachys genus. The suitable molecular marker is significant to study phylogenetic relationships in the Hypocreales order.An increasing number of molecular markers were adopted for phological analysis, fueled by the advances in sequencing technology. However, phylogenetic studies are still at the adverse state due to species heterogeneity and lack of data. Therefore, finding effective molecular markers is of high importance for the gle copy , which a animals ,41. FurtC. solani and Clonostachys sp. were isolated from Ophiocordyceps highlandensis, C. compactiuscula was isolated from Ophiocordycepsnigrolla and C. rogersoniana was isolated from soil in Kunming, China. The fungi were transferred onto plates of potato dextrose agar  and subsequently cultured at 25 °C. The species were tested according to their microscopic morphological characteristics and through molecular analyses [Clonostachys genus, and the outgroup comprised Stanjemonium ochroroseum and Stanjemonium grisellum. Four specimens were deposited as vouchers in the Yunnan Fungi Culture Collection (YFCC) at the Institute of Herb Biotic Resources of Yunnan University with the registration numbers of YFCC 8593, YFCC 8591, YFCC 8592 and YFCC 895, respectively. Genomic DNA extraction was conducted with a fungal DNA kit , complying with the instructions of the manufacturer. The integrity of the genomic DNA was measured by 1% agarose gel electrophoresis, and the concentration was measured using NanoDrop .Four species, analyses ,43,44 anClonostachys mitogenomes were initially annotated by MFannot [https://megasun.bch.umontreal.ca/RNAweasel/, accessed on 10 December 2020) and MITOS [http://mitos2.bioinf.uni-leipzig.de/index.py, accessed on 10 December 2020) under the genetic code , four mitogenomes were inspected and annotated integrally. The PCGs’ intron-exon borders were checked by exonerate 2.2.0 software package [https://omictools.com/ogdraw-tool, accessed on 10 December 2020) [The Illumina TruSeq library was generated using the IlluminaTruseq™ DNA Sample PreparationKit , following the manufacturer’s instructions. The sequencing of four genomes was conducted on Illumina HiSeq 4000 Platform for a PE2 × 150 bp sequencing and the reads were controlled with an average quality lower than Q20. After removing unpaired, short and low-quality reads, clean reads were used. Next, the reads of mitogenomes were collected and expended of mitogenomes using by Getorganelle 1.6.4 and the clean data were assembly mitogenomes with the SPAdes 3.13.0 software package ,47,48,49nd MITOS   .C. compactiuscula, C. rogersoniana, C. solani and Clonostachys sp. were computed using MEGA 6 [http://codonw.sourceforge.net/, accessed on 10 December 2020) [Clonostachys species were determined according to Kimura-2-parameter (K2P) substitution model in MEGA6.0 [The base composition analysis of the four mitogenomes was conducted using DNASTAR Lasergene 7.1. The nucleotide length, composition, and codon usage of the complete mitogenomes of g MEGA 6 . The difg MEGA 6 . The coder 2020) . The ove MEGA6.0 . The non MEGA6.0 , and the MEGA6.0 .−10 of BLASTn searches of each mitogenome [http://tandem.bu.edu/trf/trf.advanced.submit.html, accessed on 10 December 2020) [https://bibiserv.cebitec.uni-bielefeld.de, accessed on 10 December 2020) [−5.To determine whether these mitogenomes underwent intra-genomic duplication or interspersed repeats of large fragments, we used an E-value of <10togenome . Tandem er 2020) , based oer 2020)  softwareClonostachys species, phylogenetic analyses were conducted the homologous of 14 protein-coding genes (PCGs) in the complete mitogenomes. In total, this consisted of 52 sequences downloaded from the GenBank, including among the published sequences of Hypocreales order. Furthermore, Podospora anserina (X55026) was classified as the outgroup [In order to determine the phylogentic location of four outgroup . The amioutgroup  with theoutgroup  and RAxMoutgroup ,67. The C. compactiuscula (MW030498), C. rogersoniana (MW030499), C. solani (MW0304665), and Clonostachys sp. (MW0304666). The GenBank accession numbers of mitogenomes sequences are provided in C. rogersoniana, C. compactiuscula, Clonostachys sp. and C. solani are referred to in The four newly sequenced mitogenomes were submitted to the GenBank database under the accession numbers of


Subnormothermic machine perfusion (SNMP) of liver grafts is currently less clinically developed than normothermic and hypothermic approaches, but may have logistical advantages. At intermediate temperatures, the oxygen demand of the graft is low enough to be satisfied with an acellular perfusate, obviating the need for oxygen carrying molecules. This intermediate metabolic rate, however, is sufficient to support the production of bile, which is emerging as an important indicator of graft injury and viability. In this study, we hypothesized that the biliary compartment would be more sensitive than perfusate in detecting graft injury during SNMP.To test this hypothesis in a rat model, we performed liver transplants with DCD and control liver grafts after 1 h of acellular room temperature machine perfusion (acRTMP) or static cold storage (SCS). Point of care liver function tests were measured in biliary and perfusate samples after 1 h of machine perfusion. Following transplantation, rats were sacrificed at 24 h for assessment of post-transplant graft function and histology.p < 0.0030).All point-of-care liver function tests were significantly more concentrated in the biliary compartment than the perfusate compartment during acRTMP. DCD liver grafts could be distinguished from control liver grafts by significantly higher markers of hepatocyte injury  in the biliary compartment, but not in the perfusate compartment. Classical markers of cholangiocyte injury, such as gammy-glut amyl transferase (GGT), amylase (AML), and alkaline phosphatase were detectable in the biliary compartment, but not in the perfusate compartment. In comparison to SCS, graft preservation by acRTMP produced a significant survival benefit in DCD liver transplantation (75 vs. 0%, Together, these findings demonstrate that during acRTMP, the biliary compartment may be a more sensitive indicator of graft injury than the perfusate compartment. Moreover, acRTMP provides superior graft preservation to SCS in rat DCD liver transplantation. Ex vivo machine perfusion has emerged as a superior method for graft preservation over static cold storage (SCS) in liver transplantation , the Control + 1 h acRTMP group , the DCD30 + 1 h SCS group . Experimental protocol is indicated in Inbred male Lewis rats weighing 250–300 g  were used as both graft donors and recipients for syngeneic orthotopic liver transplantation. The animals were housed in accordance with National Research Council guidelines, and the experimental protocols were approved by the institutional animal care and use committee at Duke University . The animals were divided into three groups: the DCD30 + 1 h acRTMP group  for 5 min at 2 L/min of 100% Oxygen . The abdominal cavity was accessed via a cruciate incision, then anesthesia was maintained at 0.5–1% isoflurane for the duration of the procedure. The left phrenic vein was ligated and divided between 7 and 0 Silk ties. The liver was freed of its surrounding ligaments by sharp dissection. The infrahepatic vena cava (IHVC) was mobilized by blunt dissection and elongated by ligation and dissection of the right adrenal vein, the posterior lumbar plexus, and right renal vein. The bile duct was cannulated  and bluntly dissected. The portal vein (PV) was mobilized, and its most proximal side vessels  were ligated and divided between 7 and 0 Silk ties. The hepatic artery was ligated and divided. In the DCD30 groups, The PV was cross clamped, and a sternotomy was performed to induce bilateral lung collapse, marking the start of ischemic time, for a total of 30 min. The grafts were flushed with 50 ml of ice-cold HTK solution , followed by graft excision.2 and 5% CO2) to oxygenate the perfusate and ensure a minimum inflow PO2 >500 mmHg. Portal vein flow rate was set at 3 ml/min/g liver tissue. Portal vein pressure was continuously monitored using a digital differential pressure manometer , connected directly to the portal venous line via a transducer protector . At the end of machine perfusion, grafts were cooled down again with an ice-cold 100-ml HTK flush at a maximum of 15 mmHg through the portal vein, then transferred back to the surgery room packaged in ice-cold HTK.Machine perfusion was performed in a circuit that consisted of a perfusate reservoir situated underneath a graft chamber, a peristaltic pump, and a membrane oxygenator . The livPerfusate samples were collected before the liver was connected to the circuit (T0h) and at the end of the perfusion (T1h). A single bile sample consisting of the entire bile volume that was produced during the 1 h acRTMP was collected at the end of perfusion and its volume was quantified via reverse pipetting. Both perfusate and bile samples were tested for glucose level using One touch Verio flex™ handheld glucometer , lactate level using Lactate plus™ handheld , and liver function panel using Piccolo Xpress™ chemistry analyzer .2 flow at 3–4 L/min, on a heating pad, for 1-h to recover.Upon the end of the preservation period, the portal vein cannula was removed and the portal vein and infrahepatic inferior vena cava (IHIVC) were cuffed using cuffs fashioned from 16-gauge PTFE extruded plastic tubing  and 14-gauge angiocath , respectively, as described by Delrivière et al. . The supOn POD1, the recipients, if found alive, were re-anesthetized and the abdominal incision re-opened. A blood sample was collected from the IHIVC into EDTA anticoagulation tubes, and liver sections were resected and fixed in 10% NBF. The blood samples were analyzed for glucose level using One touch Verio flex™ handheld glucometer , lactate level using Lactate plus™ handheld , and Liver function panel using Piccolo Xpress™ chemistry analyzer . Liver tissue was embedded in paraffin, processed, and stained with H&E for reading of the Suzuki injury scores  by a blit-test was applied to compare values for each nominal parameter independently. One-way ANOVA was applied to compare ordinal values. The results were deemed statistically significant if time point comparisons had a P-value <0.05. Statistical significance is indicated in each figure where applicable. Figures were created using Graphpad prism, Microsoft Powerpoint, and Biorender.com.A paired Student's Both control and DCD liver grafts were maintained at a fixed portal vein flow rate of 3 ml/min/gram tissue . Portal Bile volume production during 1 h of acRTMP was similar between control and DCD grafts . Bile/peFollowing 1 h of preservation of liver grafts by either acRTMP or SCS, the caudate lobe was biopsied and processed for histological examination. DCD grafts, preserved by either SCS or acRTMP, demonstrated significant injury, with most grafts demonstrating a Suzuki score of 4 , 6. In cSurvival to the post-operative day 1 study endpoint was compared for all groups . Liver tFor animals who survived to the post-operative day 1 study endpoint, several markers of graft injury and function were measured in the blood. AST and ALT were significantly higher in the DCD group in comparison to control, but there were no differences in any of the other measured parameters .Liver grafts were biopsied and processed for histologic examination at the study endpoint. There were no significant differences in graft level of injury by Suzuki score between surviving control and DCD liver grafts, all which had been preserved by acRTMP .In this study, using a rat model of subnormothermic liver perfusion followed by transplantation, we demonstrate two primary findings: (1) machine perfusion produces a significant survival benefit over SCS for DCD liver grafts, and (2) during machine perfusion, the biliary compartment appears to be more sensitive than the perfusate compartment for the detection of liver graft injury.Our findings demonstrating the potential benefits of subnormothermic machine perfusion are consistent with recent literature , 13–23, Regardless of the approach used for machine perfusion of liver grafts , one of the key issues that remains under investigation is how to best determine graft viability during the perfusion period. Most studies thus far have focused on analytes in the perfusate compartment, including markers of hepatocyte injury , 24–27 aThere are some limitations of this study that should be discussed, primarily related to study design. Since our primary interests involved graft assessment during machine perfusion and early graft function following transplantation, we chose a study endpoint of 24 h and used a syngeneic transplant model. As such, we are unable to comment on longer-term graft function, recipient survival, or the effects of alloimmunity. With regard to perfusion duration, we selected a relatively short perfusion time of 1 h in this study based on the literature that has been established for hypothermic oxygenated perfusion, in which clinical benefit has been established using 1–2 h perfusion times . This peIn conclusion, subnormothermic perfusion represents a promising approach to liver graft preservation, combining simple logistics while retaining the ability to perform graft assessment. A more comprehensive analysis of the biliary compartment to include markers of graft injury may help refine assessment of graft viability.The original contributions presented in the study are included in the article/supplementary material, further inquiries can be directed to the corresponding author.The animal study was reviewed and approved by Duke Institutional Animal Care and Use Committee.AB, NA, and MZ conceived and planned the experiments. NA, MZ, RN, GC, JM, AP, SK, and MK carried out the experiments. AB took the lead in writing the manuscript, with help from NA. All authors contributed to the interpretation of the results. All authors provided critical feedback and helped shape the research, analysis, and manuscript. All authors contributed to the article and approved the submitted version.This work was funded by NIH K08 AI150990 to AB and NIH R01 AI153274 to JP and AB.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict ofinterest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


The two strains compose a separate branch within the clade formed by the Acinetobacter calcoaceticus–baumannii (ACB) complex with Acinetobacter pittii CIP 70.29T as the most closely related species. The average nucleotide identity compared to all other species of the ACB complex was below 94.2% and digital DNA–DNA hybridization values were less than 60%. Biochemical characteristics confirm affiliation to the ACB complex with some specific phenotypic differences. As a result of the described data, a new Acinetobacter species is introduced, for which the name Acinetobacter geminorum sp. nov. is proposed. The type strain is J00019T with a G+C DNA content of 38.8 mol% and it is deposited in the DSMZ Germany (DSM 111094T) and CCUG Sweden (CCUG 74625T).Two isolates of a non-fermenting, Gram-negative bacterial strain were cultured from two throat swabs that were taken from a pair of twins during routine microbiological surveillance screening. As these isolates could not be unambiguously identified using routine diagnostic methods, whole genome sequencing was performed followed by phylogenetic analysis based on the  Acinetobacter species are environmental organisms found in soil and wetlands [Acinetobacter species causing mainly hospital-acquired infections mostly in intensive-care settings [Acinetobacter calcoaceticus–baumannii (ACB) complex comprising Acinetobacter calcoaceticus, Acinetobacter baumannii, Acinetobacter nosocomialis and Acinetobacter pittii [A. calcoaceticus is not considered clinically relevant and resistance against antibiotics is unusual.Most wetlands , usuallywetlands . Howeversettings . These asettings  and softsettings  to pneumsettings , endocarsettings  and bactsettings  with morsettings  togethersettings . These ssettings  referredpittii , in whicet al. described the species Micrococcus calcoaceticus as the first reference for an Acinetobacter species [Achromobacter so far [et al. reclassified several genera and species into the genus Acinetobacter and presented a modified description of the genus [Acinetobacter species were described (www.bacterio.net/acinetobacter.html) supplemented by 13 additional species that were non-validly published.In 1911, Beijernick  species . In 1954 so far . Finallyhe genus . At the Acinetobacter species were described clustering into the ACB complex: Acinetobacter oleivorans [Acinetobacter seifertii [Acinetobacter lactucae [Acinetobacter species were identified in the context of the weekly screening of a neonatology ward corresponding to the guidelines of the German Committee of Hospital Hygiene and Infection Prevention of the Robert Koch Institute [Acinetobacter species (apps.szu.cz/anemec/Classification.pdf). The presented results indicate that the two new Acinetobacter isolates should be classified as a new member of the ACB complex.In the last decade, three more vorans , Acinefertii  and Acctucae . In the nstitute . These iAcinetobacter. These isolates could not be unambiguously identified using a MALDI-TOF Microflex LT instrument  or the VITEK 2 GN identification system (bioMérieux) [A. baumannii complex with a MALDI-TOF score value below 2.0. For a clear identification at the species level, a MALDI-TOF score >2.0 is expected and a delimitation of the best match is ensured by a score >0.3 higher compared to the next species.Microbiological screening of all patients is routinely performed on the neonatal intensive care unit of our university hospital. Two throat swabs from a pair of twins yielded two isolates that belonged to the genus Mérieux) . The besBacterial DNA was extracted from cultures grown on Columbia agar with 5% sheep blood (Becton Dickinson) using the DNeasy UltraClean Microbial Kit (Qiagen) following the manufacturer’s instructions with some minor modifications. Libraries for WGS were prepared using the TruSeq DNA HT Sample Prep Kit (Illumina) with 96 different barcodes using standard protocols as described previously . NormaliAcinetobacter type strains  were used for phylogenetic analysis of the two Acinetobacter isolates. ProgressiveMauve (version 2.3.1) [Acinetobacter genomes including the two new Acinetobacter isolates, representing all published Acinetobacter species up to the time of writing. Prophage regions were investigated using phaster (phaster.ca) [Acinetobacter species isolates applying iq-tree with 1000 bootstrap replicates using the UFboot algorithm. rpoB (β-subunit of RNA polymerase) sequences, used for a recent description of new Acinetobacter species as the most reliable method for species delineation [gamma rates [Acinetobacter type strains was assessed by JSpecies (version 1.2) [blast+ 2.20.29 (ANIb). The Genome-to-Genome Distance Calculator (GGDC 2.1) using the recommended Formula 2 was applied for in silico genome comparison and computation of digital DNA–DNA hybridization (dDDH) values [WGS data of publicly available n 2.3.1)  using dester.ca) . The mulineation , were exma rates . Visualiion 1.2)  based on) values .Acinetobacter isolates were performed using the standard panel for Acinetobacter species (www.szu.cz/anemec/Phenotype.pdf) by the Laboratory of Bacterial Genetics, National Institute of Public Health, Prague, Czech Republic, as described previously [Assimiliation and temperature growth tests of the new eviously .Motility assays were performed as described earlier  and wereAcinetobacter study isolates was analysed in relation to other available Acinetobacter type strains using WGS data. The 16S rRNA gene has only a limited polymorphism for discrimination of Acinetobacter species [A. baumannii ATCC 19606T can be clearly separated from J00019T using 16S rRNA gene analysis with an identity of 97.33%. Therefore phylogenetic analysis was conducted based on the full-length housekeeping-gene rpoB , the direct neighbour in the phylogenetic tree. In comparison, the ANI value between the two study isolates (J00019T and J00460) was 99.98%, demonstrating their close relationship  and compared with the six species of the ACB complex with validly published names. The data are concordant with published data [Acinetobacter species has some unusual characteristics as it is not able to grow with adipate, azelate and 4-hydroxybenzoate. The inability to assimilate these three substances separate the novel Acinetobacter species from the closely related A. pittii. Additionally, J00019T and J00460 were negative for the assimilation of l-arabinose, l-leucine, l-phenylalanine and phenylacetate, whereas most A.pittii isolates as well as A.dijkshoorniae/A.lactucae were positive in this test. The inability to assimilate l-phenylalanine and phenylacetate can also be used to separate the two novel Acinetobacter isolates from A. calcoaceticus. Strain J00019T can be distinguished from A. baumannii by being negative for glutamyl-arylamidase pNA and positive for tyrosine arylamidase. The swarming inability of strain J00019T on motility agar plates allowed phenotypic discrimination of the new species from A. oleivorans (data not shown).Phenotypic discrimination of the different members of the ACB complex is challenging as described previously . Biochemhed data  of the AT, strain J00460 and A. pittii DSM25618T performed in quadruplicate resulted in specific peaks for the two Acinetobacter species with high masses. This indicates that strains J00019T and J00460 belong to a different species compared to the most closely related A. pittii type strain as well as to 17 verified A. pittii isolates included in our MALDI database (data not shown).Detailed MALDI-TOF analysis using a Microflex LT instrument  for strain J00019rpoB and WGS data, calculation of genome relatedness by ANI and dDDH as well as biochemical properties classifies strains J00019T and J000460 as a new species within the genus Acinetobacter for which we propose the name Acinetobacter geminorum sp. nov. with J00019T as the type strain.Taken together, phylogenetic analysis based on Acinetobacter geminorum .Gram-stain-negative, oxidase-negative, catalase-positive, non-fermenting, non-motile, strictly aerobic, rod-shaped bacterium. The colonies are grey, slightly shiny, convex and circular with 1 mm in diameter after 24 h of growth on blood agar plates. Temperature from 37 to 41 °C is tolerated and no haemolysis is observed.l-glutamate, glutarate, l-histidine, dl-lactate, d-malate, malonate and l-ornithine. In contrast to most of the ACB complex strains, J00019T and J00460 are negative for assimilation of adipate, l-arabinose, azelate, 4-hydroxybenzoate, l-leucine, phenylacetate and l-phenylalanine.The physiological profiles of the two strains are congruent with those of the ACB complex. The strains are able to assimilate acetate, citrate (Simmons), Acinetobacter geminorum is J00019T, isolated from a throat swab of a patient hospitalized at the University Hospital Tuebingen, Germany. The G+C DNA content of the type strain is 38.8 mol%. The culture certificate accession numbers are CCUG 74625T from the CCUG, Göteborg, Sweden, and DSM 111094T from the DSMZ, Braunschweig, Germany.The type strain of Click here for additional data file.


Child and Adolescent Psychiatry and Mental Health (CAPMH) was founded in 2007, an initiative of Prof. Fegert. He served as the Editor-in-Chief, with support from Dr. Benedetto Vitiello  as Deputy Editor-in-Chief and Prof. Goldbeck (Germany) and Jacinta Tan (UK) as Associate Editors. The journal was the first independent, open access, online journal in the field with the mission to provide an international platform for rapid and comprehensive scientific communication on child and adolescent mental health issues from diverse cultures and contexts.The first issue of CAPMH was released in 2007. In February 2013, CAPMH became the official journal of the International Association for Child and Adolescent Psychiatry and Allied Professions (IACAPAP) and has later also been affiliated with the European Association for Forensic Child and Adolescent Psychiatry, Psychology and other involved Professions (EFCAP). Since its inception, the journal has grown rapidly and has received funding by different foundations. However, the journal also faced difficulties and setbacks as sadly, Prof. Goldbeck, one of the founding editors, unexpectedly passed away in 2017.To further establish the journal in the field of child mental health, the editorial work assertively to establish an impact factor. CAPMH was under consideration to receive an impact factor in 2009 and 2011. Finally, an impact factor was received in 2015. The current impact factor for 2020 is 3.033—a remarkable achievement given the young age and broad mission of the journal. With the new impact factor, the journal has climbed up to rank 37 in Pediatrics, ranks 91 in Psychiatry  and remains at rank 66 in Psychiatry , underlining the importance of the journal in the field of child mental health.The growth of the journal is also reflected in the number of submissions received. Most notably, a dramatic increase in submissions was observed after the journal was awarded an impact factor. Another indicator for the success of the journal is the number of downloads of published articles. With now almost 8,00,000 downloads per year, scholars and practitioners publishing within the journal reach a vast readership worldwide.Since its foundation the aim of the journal has been to increase the knowledge base related to the diagnosis, prognosis and treatment of mental health conditions in children and adolescents, and to integrate basic science, clinical research and the practical implementation of research findings . FurtherOne outstanding attribute of CAPMH as the first worldwide open access journal in the field of child and adolescent psychiatry, is its international focus. This is reflected by the international editorial board, submissions, publications, and accesses from all over the world. Thematic series focusing on child and adolescent psychiatry in Africa  and AsiaBesides the publication of incoming manuscripts, CAPMH has focused on specific topics in child and adolescent psychiatry throughout the years. The latest thematic series focuses on the impact of the Covid-19 pandemic  and is cThe success of the journal would not have been possible without the work of the committed editors, the editorial board and reviewers. In November 2021 the journal has undergone a new transition as Prof. Fegert stepped down as from his role as Editor-in-Chief and Dr. van Schalkwyk and Dr. Witt have assumed the role together. The new Editors-in-Chief want to express their deep gratitude to the founding editors of Child and Adolescent Psychiatry and Mental Health, who laid the foundation for this exciting project. They want to especially thank Prof. Fegert who has led and shaped the journal since its foundation in 2007. With his work he profoundly contributed to the reach and success of the journal and as the founding editor he stays associated with the editorial team Their thanks also go out to all editors who have been and are currently working with the journal, as well as the editorial board and the vast number of reviewers who have supported the journal throughout the years.The aim of the new Editors-in-Chief over the next years to come is a continuation of the excellent work of Child and Adolescent Psychiatry and Mental Health and to further advance the impact of the journal in the field. As the flagship journal of the International Association of Child and Adolescent Psychiatry and Allied Professions (IACAPAP) the Editors-in-Chief seek to provide a scientific platform for high quality research and practice in this area by ensuring a rigorous and timely review process. To ensure a timely and quality review process, the aim is to build a reliable and committed board of reviewers that form a relationship with the journal. To further increase the impact of the journal in the field, the aim is to establish thematic series on a regular basis. Such thematic series can address pressing issues of the time and be edited by guest experts or by editors of the journal.As an international journal for the area of child and adolescent psychiatry and mental health, the vision of the new Editors-in-Chief is to create an international scientific platform that addresses all professions in mental health. As the journal should reflect this international focus, the aim is to increase diversity among the editorial board not only in regards to gender and ethnicity, but also concerning professional backgrounds, methodological and scientific orientation. Therefore, the aim of CAPMH is to attract researchers from all over the world to submit their work to the journal not only from developed countries but also to support high quality work from less developed countries to further advance science and practice in the field of child and adolescent psychiatry and mental health.


Saphenous vein graft aneurysm is an uncommon condition and knowledge about its natural history, and a multi‐specialty heart team approach is of utmost importance for better clinical outcomes. This case highlights importance of percutaneous intervention as a viable therapeutic option in the case of saphenous vein graft aneurysms. Saphenous vein graft aneurysm is an uncommon condition and knowledge about its natural history, and a multi‐specialty heart team approach is of utmost importance for better clinical outcomes. This case highlights importance of percutaneous intervention as a viable therapeutic option in the case of saphenous vein graft aneurysms. We present a case of spontaneous SVGA hemorrhage in a 25‐year‐old graft, treated with a covered stent while preserving blood flow to a large myocardial territory.An 82‐year‐old woman with a history of coronary artery bypass graft (CABG)  to posterior descending artery and sequential SVG to obtuse marginal(OM) 2 and 3) in 1995, prior drug‐eluting stent placement in SVG to OM and mitral regurgitation treated with percutaneous edge‐to‐edge repair 6 years ago, and an episode of paroxysmal atrial fibrillation 6 months ago who was found to have an extra‐cardiac echo‐reflective 2.8 × 3.6 cm mass compressing left atrial appendage on precardioversion transesophageal echocardiogram (TEE) Figure  was perfIn the ER, she was found to be hypotensive BP 80/52 mm Hg) with a hemoglobin of 10.4 g/dL from 13 g/dL 6 months earlier. Electrocardiogram was unremarkable.  but with significant clinical consequences.Atherosclerotic degeneration of SVGs is thought to be the cause for late graft aneurysmal dilation due to weakening of the vessel wall.Although a third of SVGAs are reported as an incidental mass on chest x‐ray, chest pain is the most common (46.4%) presenting symptom followed by shortness of breath (12.9%), myocardial infarction (7.7%), shock (4.3%), hemoptysis (3.8%), and syncope (1.9%).Diagnostic assessment involves confirmation of the diagnosis, evaluation of the extent of the problem including size and location of the SVGA, mechanical complications, patency of the graft, myocardium supplied by the graft, status of other grafts or native coronaries, additional cardiovascular conditions needing intervention such as valvular abnormalities, procedural risk and feasibility review, and hemodynamic stability. The vast majority of SVGAs are reported to have significant clot burden inside them, hence potentially impact the findings of coronary angiography.In our case, CT scan and coronary angiography were performed during the acute presentation of the patient and SVGA was first suspected on transesophageal echocardiogram performed for other reasons, as an incidental finding followed by confirmation of the diagnosis on CT scan.CT helps define the anatomy of the SVG aneurysm and its relation to surrounding structures. When active bleeding is suspected, it helps identify the site of bleeding, the size of the aneurysm, any compressions of surrounding mediastinal or cardiac structures, and hence plan therapeutic intervention, that is, open vs endovascular repair. This is especially significant in cases, where prior CT imaging is unavailable. In such cases, it helps define position of the aneurysm in reference to aortic or coronary attachment and neighboring structures. It can also help assess the effect of bleeding aneurysm on neighboring structures. Cardiac MR is a more time‐consuming diagnostic tool and can be of help in stable conditions to better assess anatomy. In many cases, MR angiogram can be suboptimal to assess the vascular details due to respiratory variabilities. Depending upon the expertise of different centers, preference between CT and MR can be variable. Considering acute presentation, CT was the preferred modality by emergency team in this case.Optimal treatment selection for SVGAs should be based on detailed vascular anatomical features and patient‐related factors. The most prevalent management approach for SVGAs is surgical (>50%), followed by conservative care (20%). Surgical procedures include ligation or resection of the graft followed by placement of a new graft in cases, repair, or placement of interposition graft.Intravascular imaging such as IVUS can be very useful to assess the vessel size for appropriate stent selection. Current coronary covered stents can be used (off‐label) to treat SVGAs with reference vessel diameter up to 5.5 mm and off‐label use of peripheral stents in SVGAs with larger reference vessel diameter. If a 0.035” wire cannot be safely placed in the vessel under treatment, two or three 0.014” wires can be placed in the SVG and used as a railing to deliver an appropriately sized peripheral stent. Based on CT images available, aneurysmal segment was in the body of the graft with a good proximal and distal reference vessel for appropriately sized stent (landing zones). The size of stent needed was more of a dynamic decision process. Considering the emergent nature of the procedure, two supportive coronary wires were placed in case needed as railing for a peripheral covered stent in a large bore saphenous graft. However, Eagle‐Eye IVUS (intra vascular ultrasound) catheter used revealed a reference vessel diameter of 4.8 mm, compatible with a coronary covered stent.As noted in peripheral the vascular bed, SVGAs may grow in size over a period of just 6 months.3A multi‐specialty heart team approach with prompt diagnosis, imaging, and treatment in acute presentation of SVGA leads to favorable outcomes.All authors have declared they have no conflicts of interest relevant to this manuscript.Eric Gnall: drafted the manuscript, the main conceptual ideas, and proof outline. Manju Bengaluru Jayanna: careful editorial and technical review, critical revisions of the manuscript. Timothy Shapiro: careful editorial review, provided critical feedback, and helped shape the manuscript. Muhammad Abdulbasit and Maria Elena Drosou: careful editorial and critical revisions of the manuscript. Tariq Ahmad: drafted the manuscript, the main conceptual ideas, supervised the work and as the corresponding and as the last author, is the main person responsible for the contents of the article. All authors discussed, contributed, and approved the final manuscript.As a case report, this work was exempt from need for IRB approval.Video S1Click here for additional data file.Video S2Click here for additional data file.Video S3Click here for additional data file.Supplementary MaterialClick here for additional data file.


Supplemental Digital Content is available in the text. Nonpathogenic torque teno viruses (TTVs) are highly prevalent in transplant recipients and associated with immunosuppression. Studies in kidney transplant patients have proposed assessment of TTV load for risk stratification of clinically overt graft rejection. The value of TTV quantification in the context of subclinical rejection has not been evaluated.In this prospective trial, 307 consecutive kidney transplant recipients were subjected to per-protocol monitoring of plasma TTV. TTV was analyzed in the context of protocol biopsies (n = 82), scheduled 1 year posttransplantation.P = 0.004). Development of chronic lesions  was associated with the number of days with a TTV load <1 × 106 copies/mL between months 3 and 12 posttransplant .TTV load at the time of biopsy was lower in recipients with rejection  than those without rejection (n = 63) whereby each log increase in TTV copies/mL decreased the risk for rejection by 9% (risk ratio 0.91, 95% confidence interval, 0.85-0.97; 6 copies/mL suggests suboptimal immunosuppression.This trial demonstrates an association between TTV and subclinical graft rejection in kidney transplant recipients. A TTV load <1 × 10 At present, there is no diagnostic test or algorithm available for the optimal guidance of immunosuppressive drugs in the clinical routine.2 Monitoring is mainly based on the quantification of the calcineurin inhibitor trough level in the peripheral blood, which correlates more closely with the risk of drug-related toxicity than with effectiveness of the immunosuppression.3Immunosuppression after kidney transplantation is crucial for reducing the risk of organ rejection. Despite this benefit, the compromised immune competence of the recipient leads to an increased risk for infectious disease. Moreover, current immunosuppressive regimens are unable to sufficiently control the allorecognition of the graft in some patients, which may lead to chronic rejection.4 The prevalence of TTV in immunocompromised patients after transplantation is up to 100% and the virus is unaffected by conventional antiviral drug therapy used in the posttransplantation setting.4 The TTV load is directly associated with the amount and type of immunosuppressive drugs administered to the transplant recipient and is thus indirectly associated with graft rejection and infectious disease.4 In kidney transplant recipients, recent data suggest TTV quantification for risk stratification of clinically overt graft rejection.8 However, no study has analyzed the association between TTV and subclinical rejection.Monitoring the torque teno virus (TTV) is a promising new strategy for quantifying the immune function. TTV can be detected in up to 90% of healthy individuals and has not been linked to any human disease.http://links.lww.com/TP/C104). The inclusion criterion was the availability of a protocol biopsy of the kidney graft scheduled 1 year after transplantation. Exclusion criteria were a protocol biopsy earlier than month 9 or later than month 15 posttransplantation, an unstable graft function , a presumptive polyomavirus nephropathy , and an active participation in interventional trials, respectively. The patients were followed at the outpatient clinic of our center until protocol biopsy or drop out due to a change of posttransplant care center, graft loss, or death. The present study was approved by the local institutional review board (1785/2016) and registered at the German Clinical Trials Registry (DRKS00012335).All 307 consecutive adult (≥18 y of age) recipients of a kidney allograft transplanted at the Medical University of Vienna, Austria, between December 1, 2016 and December 31, 2018, were screened. Standard of care is described in the Supplement Digital Content  were defined by foci of tubulitis (t > 0) with the presence of interstitial inflammation (i > 0) in the primary analysis. For a sensitivity analysis, we used a broader definition of BL TCMR, based on the presence of foci of tubulitis (t > 0) with and without an interstitial inflammation (i). The immunohistochemical assessment of the C4d staining was evaluated on paraffin-embedded sections. The dynamic of chronic lesions in the “month 12” protocol biopsies was assessed by comparing with a “month 3” protocol biopsy or a preimplant biopsy in case of missing “month 3” biopsy (n = 3). The biopsies were assessed by 2 pathologists (J.K. and M.N.) and in case of a disagreement by a third pathologist (H.R.), all blinded to the clinical data.The primary outcome was predefined as plasma TTV load in the context of biopsy-proven graft rejection in a protocol biopsy scheduled at month 12 posttransplantation . The histologic lesions were categorized following the 2019 Banff Kidney Meeting Report.6 copies/mL as a risk factor for clinically overt rejection.8 Thus, we estimated the days with a TTV load <106 copies/mL between the “month 3” and the “month 12” biopsy for each patient, by summing the days of the intervals with a TTV load <106 copies/mL at the beginning and the end of the interval. The TTV DNA was quantified by a TaqMan real-time polymerase chain reaction, as described previously.11 Details are described in the Supplement Digital Content (http://links.lww.com/TP/C104). The treating physicians were unaware of the TTV results.TTV was quantified prospectively per-protocol in the plasma obtained from peripheral blood at the following predefined time points: before the transplantation and after the transplantation once per week until discharge from the ward, on the first visit at the outpatient clinic, at month 3 after transplantation, and every 3 months thereafter. Earlier studies from our group have described a TTV load <106 copies/mL. The effect size was displayed as a risk ratio (RR) and 95% confidence interval (95% CI). Linear regression was used to quantify the association between the sum of active histologic lesions, the development of chronic allograft injury and TTV load at the time of biopsy or TTV load <106 copies/mL. The effect size was displayed as a coefficient (β) and 95% CI. For sensitivity analysis, the primary cohort was restratified applying a broader definition of BL TCMR based on the presence of any foci of tubulitis (t > 0) with and without interstitial inflammation (i). An additional sensitivity analysis was performed on a cohort including all available “month 12” protocol biopsies. Potential confounders of the effect size of the association of TTV and rejection were assessed using a bivariate analysis. Potential effect modifiers were tested using Mantel-Haenszel strata. A change in the effect size of >10% was defined as significant. For multivariate analysis, the covariables were selected based on their clinical relevance. For the multivariate model, a backward elimination was used, and the “rule of 10” was applied to define the maximum number of the variables allowed to remain in the final model. A P value of <0.05 was the predefined limit of significance. Log normal distributed variables were log-transformed . MS EXCEL 2010 (Microsoft), IBM SPSS Statistics 24.0 (SPSS Inc.), R 4.0.3 (R Core Team), and STATA 15 (STAT Corp.) were applied for the data analysis.Generalized linear models for the binominal family were used to estimate the effect size of the association between allograft rejection, according to Banff 2019, presence of histologic lesions, and TTV load at the day of biopsy or days with TTV load <10A total of 307 patients received a kidney transplant at the Medical University of Vienna between December 1, 2016, and December 31, 2018, and 283 had a functioning graft 1 year after transplantation. The study flow is presented in Figure 2 (IQR 42–66), and the median urinary protein creatinine ratio was 94 mg/g (IQR 67–190). A graft rejection, according to the Banff 2019 Kidney Meeting Report, was diagnosed in 19 of the kidney graft recipients (23%) and 63 showed no rejection. The baseline characteristics, according to rejection status, are displayed in Table The protocol biopsies of the 82 included kidney transplant recipients were performed at a median of 13 months posttransplant (interquartile range [IQR] 12–14 mo). The median estimated glomerular filtration rate at the time of biopsy was 52 mL/min/1.72m5 copies/mL (IQR 8 × 104 to 1 × 107). Patients with graft rejection had a lower TTV load than patients without rejection . Each log increase in TTV load decreased the risk for rejection by 9% . The diagnostic accuracy to detect subclinical rejection by TTV load is displayed in Table SDC, http://links.lww.com/TP/C104).All 82 kidney graft recipients included in the primary analysis had detectable TTV at the time of the protocol biopsy with a median of 5 × 10For sensitivity analysis, the cohort was stratified by applying a broader definition of BL TCMR based on the presence of foci of tubulitis (t > 0) with and without interstitial inflammation (i). Thirteen biopsies were reclassified as BL TCMR, leading to a total number of 32 rejections. A similar effect size of the association between the TTV load and rejection compared to the primary analysis was found . A second sensitivity analysis was performed on the full set of protocol biopsies (n = 102), including all 20 biopsies excluded from the primary analysis because of timing, graft function, presumptive polyomavirus nephropathy, and active participation in an interventional drug trial. Within this cohort, 4 additional rejection episodes were diagnosed, 2 BL TCMR and 2 chronic active TCMR, meaning that a total number of 23 recipients experienced graft rejection. A similar effect size of the association between the TTV load and rejection compared to the primary analysis was found .Subgroup analysis restricted to the patients with an AMR (n = 4) revealed an effect size of the association between rejection and TTV load comparable to the primary analysis, including all rejections . Similar results were obtained in a further subgroup analysis restricted to TCMR . The largest effect size of the association between rejection and TTV load was obtained in the final subgroup analysis restricted to AMR and TCMR excluding BL TCMR .To test whether the TTV load was independently associated with rejection, predefined potential confounders were analyzed, and the adjusted RR was calculated Table . None ofP= 0.02). Kidney graft recipients with active lesions had a lower TTV load at the time of biopsy than patients without such lesions . TTV load stratified according to histologic lesion is displayed in Figure S2 . The risk for the presence of active lesions decreased by 4% with each increase in the TTV log level . The effect size of the association between the presence of each active histologic single lesion and the TTV load at the time of biopsy is displayed in Table In 63% of the patients (n = 51), at least 1 active single lesion including g, v, t, i, ti, ptc, iIFTA, tIFTA, or C4d was detected in the “month 12” protocol biopsy with a median lesion sum of 3 (IQR 0–6) per individual. The sum of active lesions was associated with the TTV load . The increase in chronic lesions was associated with the days with a TTV load <106 copies/mL within the same period of time . The diagnostic accuracy to detect development of chronic lesions by days with a TTV load below 106 copies/mL is displayed in Table SDC, http://links.lww.com/TP/C104). The effect size of the association between the development of each chronic histologic single lesion from months 3 to 12 and the days with a TTV load below 106 copies/mL within the same period is displayed in Table 6 copies/mL stratified according to histologic lesion is displayed in Figure S4 .Almost all patients n = 79, 96%) had detectable chronic lesions including cg, cv, ci, ct, ah, and ptcml in the “month 12” protocol biopsy with a median lesion sum of 4 (IQR 3–6) per individual. The dynamic of the chronic lesions was analyzed in the context of a protocol biopsy scheduled 3 months posttransplantation . The median sum of the increase in chronic lesions from the “month 3” to the “month 12” biopsy was 1 per individual (IQR 0–3). To assess the association between a low TTV load and the devolvement of chronic graft damage over time we calculated the days with a TTV load <10% had detThe major finding of this trial was the establishment of a robust association between allograft rejection and TTV load in clinically stable patients 1 year after kidney transplantation. Subclinical alloreactivity and the development of chronic graft injury were associated with a low TTV load suggesting improved virus control due to a less suppressed immune system. Early recognition of insufficient immunosuppression might offer a therapeutic window to optimize immunosuppressive drugs. Such personalized adaption of the immunosuppression might reduce alloreactivity and subsequent graft injury and thus provides a valuable strategy with the potential of being tested in a randomized controlled setting.13 Reanalysis of the cohort, applying a more sensitive threshold for BL TCMR, described a similar effect size of the association between TTV load and graft rejection. This finding links tubulitis without interstitial inflammation with low immunosuppression. Indeed, a recent report suggests tubulitis without interstitial inflammation as a risk factor for acute rejection and graft loss.14 The largest effect size of the association between the TTV load and histologic changes was detected in a compound endpoint, including all the single lesions suggestive for active alloreactivity and a subgroup analysis restricted to AMR and TCMR excluding BL TCMR. These findings suggest that TTV load best reflects the total amount of active alloreactivity and the more severe rejection episodes, respectively. We describe a comparable effect size of the association between TCMR, AMR, and TTV load, suggesting TTV load reflects the overall immune function, rather than an isolated T-cellular specific immune response. Statistical tests were only performed for the primary outcome. Therefore data concerning subgroup analysis and secondary outcomes including histologic lesions have to be interpreted with caution and might only be hypothesis generating. Of note our dataset does not include acute TCMR I or more severe cases, limiting the generalizability of our results for such rejection classes.The primary analysis of the present trial was restricted to stable patients. However, a comparable effect size of the association between TTV load and rejection was calculated for the total unselected cohort. Therefore selection bias is unlikely. The primary outcome included BL TCMR, as recent data suggested a clinical significance of such pattern in biopsies taken 1 year after kidney transplantation.8 However, for TTV loads <106 copies/mL increasing specificity for the prediction of subclinical rejection was calculated from our data. Moreover, TTV load in patients experiencing rejection or histologic lesions suggestive of alloreactivity was 105 copies/mL compared to 106 copies/mL in patients without rejection and without such lesions, respectively. The development of chronic graft injury was associated with the number of days with a TTV load <106 copies/mL, a cutoff that has already been suggested as a critical risk factor for clinically overt rejection in earlier studies from our group.8 However, only a modest accuracy for the number of days with a TTV load <106 copies/mL to predict the development of chronic lesions was calculated from our present data. Of note, specificity to detect chronic changes rises if a TTV load below 106 copies/mL was detected for >90 days. In this respect, it is important to note, that TTV was measured every 3 months per protocol. Therefore our findings might suggest, that at least 2 measurements of a TTV load <106 copies/mL or a TTV <106 copies/mL during a period of >3 months are needed to increase the risk for chronic graft injury. Taken together, diagnostic accuracy of TTV to predict subclinical graft injury is only modest. However, our data suggest TTV loads <106 copies/mL as a useful target to be tested in a larger multicenter prospective setting or interventional trials.Our results describe only a modest accuracy of TTV load to detect subclinical rejection. In this respect, our report is in line with published work on clinically overt rejection.15 and a commercial TTV assay was introduced in 2017.16 Such tools will facilitate prospective, large scale multicenter studies necessary to test the findings from our report. Finally, our study design cannot prove causality between TTV and immunosuppression or clinical relevance of the association between TTV load and subclinical rejection. Interventional trials based on TTV load are needed to analyze the value of TTV-guided drug dosing .A limitation of the study is the high rate of loss to follow-up. Of note, baseline characteristics were similar in the total cohort, the cohort with a functioning graft 12 months posttransplantation and the cohort included in the primary analysis. Therefore selection bias is unlikely. Another limitation is the sample size and the single-center design. Differences in baseline characteristics and posttransplantation care might reduce generalizability of our results. Intercenter variability of TTV PCR might further complicate comparability of TTV loads reported in this article. In this respect, it is important to note that a standardization process for the TTV quantification was initiated in 2018 with high accuracyThis trial is the first to associate TTV load and alloreactivity in stable kidney transplant recipients. Multicenter and interventional studies are needed to test the value of TTV quantification for the guidance of immunosuppression.The authors would like to thank Gabriele Rath, Habiba Ahmed, and Luis Naar for their excellent support in clinical data collection.


R2) of the established models is all greater than 95%, indicating that the established models are highly reliable and can be used to predict the aging days, crystallinity, and retrogradation degree of starch. And the R2 of the prediction model based on the refractive index spectrum is greater than that of the absorption coefficient spectrum. The experimental method obtains the dynamic fingerprint identification map of starch in the aging process, realizes the real‐time monitoring and detection of the starch aging process, and provides an effective means for the production and processing of starch‐related industries.Traditional methods for the determination of starch aging indicators often have a series of shortcomings such as time‐consuming, high cost, large human error, damage to samples, environmental pollution, and high requirements for inspectors. Therefore, it is meaningful to find or establish a dynamic fingerprint identification pattern that can detect the aging degree of starch during the process of processing or storage quickly and accurately. It not only provides guidance for starch food processing but also saves a lot of human, material resources, and time. Terahertz technology is an emerging molecular spectroscopy technology in the 21st century. It is with low energy and basically harmless to the human body. It can also realize nondestructive testing of samples. In the experiment, the samples were prepared by the tableting method and the samples containing 20% of 50 mg samples were prepared with polyethylene as the diluent. The thickness of the samples was 1 mm and the diameter was 13 mm. The terahertz time‐domain spectrometer was used to obtain the spectral information of aging starch at different aging times. After the pretreatment of the spectrum by vector normalization, first derivative, and multiple scattering correction, the prediction models of aging days, crystallinity, and resilience of aging starch were established, respectively. The determination coefficient ( R2) of the established models were all greater than 95%, indicating that the established models had high reliability and could be used to predict the days, crystallinity, and degree of regression of starch aging. This paper provides a solid foundation for real‐time monitoring and determination of aged starch.The determination coefficients ( This method saves a lot of manpower and material resources for the determination of starch‐related properties and provides a solid foundation for future research on starch‐related properties.Intermolecular forces such as hydrogen bonds, low‐frequency vibrations of the crystal lattice, and macromolecular skeleton vibrations all occur in the terahertz band, and these vibrations all reflect molecular structure information. The aging process of starch is the hardening phenomenon produced by the continuous association of hydrogen bonds between molecular chains. Therefore, it is feasible to use terahertz technology to study the relevant characteristics of starch aging. In this study, a terahertz time‐domain spectrometer was used to collect the terahertz spectrum at different aging times from 0 to 35 days. After preprocessing the spectra by vector normalization, first derivative and other preprocessing methods, the models of aging days, crystallinity, and retrogradation were established. The determination coefficients ; NaOH solution; HCl solution; I2.2Terahertz time‐domain spectrometer (CCT‐1800); Milli‐Q ultra‐pure water system (Milli‐Q Reference); Powder press machine (BJ‐15); X‐ray diffractometer (Bruker D8); UV‐visible spectrophotometer (U‐3900); pH meter (PB‐10).2.32.3.1Add 20 g starch into 200 ml deionized water, mix it well, and put it into a sealed sterilization pot. Heat it under steam at 120℃ for 20 min to gelatinize it. The gelatinized samples were quickly cooled to room temperature and stored in a refrigerator at 4℃ for 0, 1, 3, 5, 7, 14, 21, 28, and 35 days. After taking it out, freeze, dry, and crush it at −80℃ and pass through 100‐mesh sieve. Keep in a dryer for later determination.2.3.2The SU‐3500 scanning electron microscope of Japan HITACHI company was used for micro‐scanning. Place the raw starch and each retrograded sample evenly on the carbon conductive glue and fix it on the sample table and then observe. Observe with different magnifications and angles such as 50×, 100×, 200×, 400×, 800×, 1,200×, 2,000×, etc. Use the software that comes with the instrument to take pictures.2.3.3XRD technique measured the crystallinity of aged starch. After the starch is completely gelatinized, there is no endothermic peak in XRD. When starch ages, internal amylose, and amylopectin are rearranged to form recrystallization. At this time, the crystal structure of starch is destroyed and additional energy must be added. Therefore, the endothermic peak will appear in the aged starch in XRD, and the greater the degree of starch aging, the greater the endothermic peak. Therefore, the crystallinity of aged starch can be measured by XRD technology  when the sample is not placed and the sample time‐domain signal Esam (t) when the sample is placed. The frequency‐domain signals Eref (ω) and Esam (ω) of the reference and sample are obtained after Fourier transform. The refractive index and absorption coefficient of the sample were obtained by data processing using the methods proposed by Dorney and Duvillaret  is the refractive index of the sample and ω the frequency. φ(ω) the phase difference between the sample and the reference signal, φω=φsample(ω)‐φref(ω). where c is the speed of light and d the thickness of the sample.The refractive index was calculated according to the following equation:α(ω) is the absorption coefficient of the sample and n(ω) the refractive index of the sample. A(ω) is the amplitude ratio of the sample to the reference signal. Where d is the thickness of the sample and ω is the frequency.We can obtain the absorption coefficient from the following equation:The time‐domain spectrum, frequency‐domain spectrum, refractive index spectrum, and absorption coefficient spectrum of aging starch are inherently related. With the prolonging of aging time, the crystallinity increased gradually, the content of regenerated starch increased and the absorption of terahertz wave was enhanced. As a result, the transmittance of the terahertz wave is weakened, the time required for complete transmittance is increased and the peak intensity is reduced with a time delay phenomenon. In Figure 3.43.4.1Analyze the obtained spectra, preprocess the spectra firstly and find the optimal preprocessing method by preprocessing the spectra through different preprocessing methods. Table R2 is, the more consistent the analysis results are with the chemical analysis results, and the higher the reliability is. The lower the RMSECV is, the closer the predicted value obtained during cross‐validation in the calibration modeling process is to the chemical analysis value and the higher the accuracy of the calibration model is. It can be seen from the table that the pretreatment method of the optimal model of refractive index spectrum is the second derivative. In the optimal model, R2 is 99.09 and RPD is 10.5. The preprocessing method of the optimal absorption coefficient spectral model is the second derivative. In the optimal model, R2 is 98.77 and RPD is 8.93. The optimal model is selected as the model for predicting starch aging days. Figure The higher the determination coefficient 3.4.2Table R2 is 99.87 and RPD is 28.3. The preprocessing method of the optimal model of absorption coefficient spectrum is the first derivative. In the optimal model, R2 is 95.78 and RPD is 4.87. The dimension of the model is as shown in Figure It can be seen from Table 3.4.3Table R2 is 98 and RPD is 7. The preprocessing method of the optimal model of the absorption coefficient spectrum is the second derivative. In the optimal model, R2 is 95.34 and RPD is 4.63. The dimension of the model is, as shown in Figure It can be seen from Table 4R2 = 99.04) and absorption coefficient spectra (R2 = 98.74) of aging days are both the second derivative. The preprocessing methods used in the optimal prediction model of the refractive index (R2 = 99.87) and absorption coefficient spectra (R2 = 95.87) of crystallinity are the second derivative and the first derivative. The preprocessing methods used in the optimal prediction model of the refractive index (R2 = 98) and absorption coefficient spectra (R2 = 95.34) of retrogradation degree are both the second derivative. In this study, the terahertz time‐domain spectrometer was used to model and predict the aging days, crystallinity, and regenerative degree of starch with R2 greater than 95%, indicating that the terahertz time‐domain spectrometer can be used for qualitative and quantitative detection of bioactive substances and other macromolecular substances. Through comparison, it can be seen that the R2 of the prediction model based on the refractive index spectrum is greater than that of the absorption coefficient spectrum. Therefore, the model based on refractive index spectrum has little deviation in actual production. The experimental method obtains the dynamic fingerprint identification map of starch in the aging process, realizes real‐time monitoring and detection of the starch aging process, and provides an effective means for the production and processing of starch‐related industries.The aging phenomenon of starch in the process of processing, transportation, and storage will seriously affect the sensory and quality of starch food. Therefore, it is meaningful to understand the aging process of starch. The study on the crystallinity, and retrogradation degree of aged starch changes with aging time show that with the extension of aging time, the crystallinity, and retrogradation degree of aged starch increase. The pretreatment methods used in the optimal prediction model of the refractive index (The authors declare that there are no conflicts to declare.Tao Wang: Data curation (lead); Investigation (lead); Methodology (lead); Software (lead); Writing‐original draft (lead); Writing‐review & editing (lead). Shuya Wang: Conceptualization ; Resources . Chen Zhai: Conceptualization ; Funding acquisition (lead); Project administration (lead); Resources (lead). Liang Wang: Data curation ; Resources . Yunfeng Xie: Funding acquisition ; Resources . Qian Li: Data curation ; Software (lead). Xu Zheng: Data curation ; Software .


KT and cable pose stiffness KS. It indicated that the static stiffness of the PCUR was related to the cable tension, the arrangement of the cable, and the cable stiffness. Secondly, a simulation model in MATLAB/Simscape Multibody was built. Cable tension was applied to make the moving platform in a static equilibrium state. The stiffness of the PCUR and the external force on the moving platform were changed, and the motion characteristics of the moving platform were obtained. Finally, the position changes of the moving platform under different external forces were analyzed, and the motion laws of the moving platform under different stiffnesses were summarized.This paper studies the stiffness of the parallel cable-driven upper limb rehabilitation robot (PCUR). Firstly, it was derived that the static stiffness expression of the PCUR was composed of platform pose stiffness  Stroke has become an important issue of global concern due to its high incidence and high disability rate. Various complications such as hemiplegia caused by it have attracted attention from various fields ,2,3. In Cable-driven robots can be divided into two categories—tandem and parallel robots, while parallel robots can be further divided into suspension and constrained robots. Mao and Agrawal proposed a cable-driven arm exoskeleton robot (CAREX), which is part of a tandem mechanism. The CAREX, driven by multiple cables together, solves the problem of a single cable which does not provide thrust . Jin et Research on the stiffness control and force control of the parallel cable-driven upper limb rehabilitation robot (PCUR) can make an overall stiffness adjustment and realize an overall flexibility and a better man–machine interaction of the robot. The cable tension and the combined force of the cable acting on the moving platform are controlled. It can prevent secondary injuries to affected limbs caused by excessive force during rehabilitation training, effectively improve the overall flexibility of the rehabilitation robot and achieve safer and more comfortable rehabilitation training ,12. BrucPatients in different rehabilitation stages need different rehabilitation training modes, mainly divided into the following three modes, i.e., the passive training mode, the active training mode, and the impedance training mode ,23. The K is composed of two parts: KT is the static stiffness related to the tension of the cable, which is the leading cause of the change in the pose of the moving platform and is called the platform pose stiffness; KS is the static stiffness related to the structural parameters of the robot, which is produced by the change of the cable configuration and is called the cable pose stiffness. By controlling KT, rehabilitation can be performed at different stiffnesses. The novelty of this paper is that by building a multi-body simulation model, cable tension required to maintain a certain stiffness of the moving platform was analyzed, and different external forces were applied on the moving platform. Different stiffness conditions were combined to study the movement of the moving platform.Most previous papers have investigated the stiffness properties of cable robots at a theoretical level, and there is less literature on the stiffness properties associated with actual models. This paper analyzes the stiffness theory of the PCUR and uses it for different stiffness performance analyses, and it was derived that static stiffness The rest of this paper is organized as follows: The second part gives a brief overview of the PCUR structure. The third part carries on the mathematical modeling and the stiffness theory analysis of the PCUR. The fourth part builds the simulation model, and the range of the stiffness is solved according to the cable tension condition. The fifth part analyzes the simulation results and studies the position changes of the moving platform under different external forces and different stiffnesses. The sixth part is the summary and the prospect of the PCUR static stiffness research.The schematic of the PCUR is shown in The upper limb rehabilitation training in the form of the robot is shown in Based on the PCUR, the static analysis and stiffness analysis of the mechanism was carried out. The simulation model in MATLAB/Simscape Multibody was built, and the motions of the moving platform under external forces were studied. The performances of PCUR under different stiffnesses and the appropriate stiffness of rehabilitation training were analyzed, laying the foundation for the follow-up control of the PCUR’s stiffness.O-xyz. The local coordinate system P-x′y′z′ represents the center point position of the moving platform.As shown in The pose of the moving platform in the global coordinate system is expressed as:Li represents the vector of cable length and il represents the cable length.The unit vector ri represents the vector from the center point of the moving platform to the cable traction point and is described as:i-th cable connection point P-x′y′z′; R is the rotation matrix of the local coordinate system P-x′y′z′ relative to the global coordinate system O-xyz. Abbreviating cos to c and sin to s for the simplicity of writing, the expression of R is written as:m represents the number of cables, and n represents the degree of freedom of the mechanism; m > n), which can realize the motion in the direction of six degrees of freedom in space. The moving platform maintains equilibrium under the joint action of seven cables. The static equilibrium expression is shown as following:JT is the system structure matrix, T represents the tension vector of the cable, and F represents the generalized external force of the moving platform, including its gravity and the inertial force and the centrifugal force in the process of moving. The specific expression of the structure matrix JT is written as:The PCUR is a redundant mechanism  and (9), the following equation can be obtained:KT is written as:ui is the unit vector in the direction of the cable i vector, defined as:The expression for the platform pose stiffness KS is expressed as:Ei denotes the modulus of elasticity of the cable, Ai denotes the cross-sectional area of the cable, li is the length of the cable and the unit stiffness of the cable is taken as k = 125,000 N/m.The expression for the cable pose stiffness J, and λ is an arbitrary constant, representing the constant value of the solution space satisfying the cable tension condition.Derived from Equation (5), the following can be obtained:Tmin and Tmax represent the minimum tension and the maximum tension of a single cable, respectively. Tmin is 5 N, and Tmax is 200 N. The range of λ can be obtained from Equation (16).From Equation (15), the following can be obtained:As shown in The internal modeling and simulation of CDU1–CDU7 are shown in The result of the Multibody simulation model is shown in S = T. The generalized external force of the moving platform F was T. The center point of the moving platform coincided with the origin of the O-xyz spatial coordinate system. The range of λ was solved according to Equation (16). As shown in λ, which was .The initial state of the moving platform was λ, the relationship between the cable tension and λ is shown in λ, the tensions of the seven cables increased accordingly, and the system stiffness also increased. Hence, λ also reflected the size of the system stiffness to a certain extent. In the value range of λ, the cables tensions were in the range of 5–200 N. That is, the cable tension can be obtained according to According to the value range of λ were taken to obtain the eigenvalues of the global stiffness matrix K, of which the eigenvalues represent the stiffness values in the six-DOF direction of the space, which are represented by xK, yK, zK, αK, βK, and γK, respectively. Then, the relationship between the stiffness values in the six-DOF direction of the space and the λ can be obtained. As shown in λ value, the stiffness of the system increased. The stiffness values of the moving platform xK, yK, zK, and αK gradually increased, while βK and γK decreased progressively. The change of the stiffness value in each DOF direction was related to the PCUR mechanism’s configuration.The cable tensions under different λ value range solution. Under the λ value range of 52.57–291.48, the vertical downward external force was applied to the moving platform in the simulation model, so that the effects of different stiffnesses on the PCUR were known.The relationship between the system stiffness and the pose was further studied through the PCUR stiffness derivation, simulation model construction, and For a given stiffness, the whole system corresponded to a spring system which maintained a stable oscillation in the elastic range. A heavy ball with a mass of 0.05 kg, suspended 200 mm from a moving platform, was in a free-fall motion. When a moving platform was shocked, it was first in an impact shock period, with an increase in the amplitude of the oscillation. Then, it was in a period of stable shocks, with relatively stable changes, as shown in λ = 80, the tension value of each cable made the moving platform in the static state, that is, T = T. The overall stiffness of the mechanism was calculated by Equation (17), and the overall stiffness eigenvalues were e = T × 105.For O-xyz and the linear distance curve between the center point and the initial pose were drawn . It can be seen that the position variation of the moving platform was minimal without an external force, with a weak vibration in the 0.2 mm range. This phenomenon is that there was a slight deviation in the tension of each cable input and also by the magnitude of the gravity of the moving platform itself. In practical research, the influence is small and can be ignored.External force of 0 N , 5 N, and 10 N were applied to the moving platform. The motion data were extracted from the mobile platform, and the motion trajectories were plotted. The position change of the center point of the moving platform when the external force was 5 N is shown in In summary, from λ = 170, the tension value of each cable that kept the moving platform in a stationary state, and T was written as T. The overall stiffness of the mechanism was obtained with Equation (18), and the eigenvalue of the overall stiffness e was expressed as T × 105.The following shows the position change of the moving platform under different stiffness conditions. For λ = 260, the tension value of each cable to keep the moving platform in a stationary state T was described as T. The overall stiffness of the mechanism was obtained with Equation (19), and the eigenvalue of the overall stiffness e was described as T × 105.For λ = 80, 170, and 260, the change of the overall stiffness eigenvalue conformed to the change of the stiffness shown in Compared with the eigenvalues of the overall stiffness under the values of λ = 80, 170, and 260. The reason is due to the given force and the simulation deviation. It had little effect on the stiffness evaluation, which was ignored.Without an external force, the moving platform remained stationary under the action of seven cables. As shown in λ = 80. For λ = 170, the distance from the initial pose of the moving platform was about 90 mm. For λ = 260, the distance from the initial pose of the moving platform was about 60 mm. The greater the value of λ, the greater the system’s stiffness, and the smaller the change in the position of the moving platform.λ value was, the smaller the pose variation of the moving platform was. For λ = 80, the distance from the initial pose of the moving platform was about 330 mm. For λ = 170, the distance from the initial pose of the moving platform was about 180 mm. For λ = 260, the distance from the initial pose of the moving platform was about 120 mm.In summary, from Different stiffness performances were adapted to different rehabilitation training stages and training modes in the actual rehabilitation training. The training modes with different stiffnesses were selected according to the specific situation to ensure that the upper limb rehabilitation robot can achieve safety and comfort rehabilitation training.In this paper, by deriving the stiffness of PCUR, the theoretical expressions of the stiffness and the calculation equations of the cable tension values were obtained. The relationships between the cable tension, the stiffness value, and the value of λ taken in the direction of each degree of freedom were analyzed. Different tension values were applied to each cable, and different external forces were applied to the moving platform under the current tension value. Then, the movement of the moving platform was observed. The following two points were analyzed:When the stiffness of the robot system remained constant, the range of motion of the moving platform became larger as the applied external force increased. When the external force was too great for the system to withstand, the system would lose stability, and increasing the external force could increase the range of motion of the moving platform.When the external force applied to the moving platform remained constant and the stiffness of the robot system changed, the range of motion of the moving platform decreased as the stiffness of the system increased.Further research work will focus on two aspects:KT.The impedance controller is being designed to incorporate the force and the position into the same control system. The closed loop control of cable tension and the cable length variation will be achieved, indirectly controlling the system stiffness by controlling the platform pose stiffness λ will be linked to the actual rehabilitation training. λ will be taken automatically, depending on the training patterns and indicators expected by the rehabilitator, so that rehabilitation training has different patterns of the stiffness.