Evaluating the feasibility of a remote-based training program supported by information and communications technology in the older adults living at home

Background

Exercise has been one of the key strategies for preventing frailty. While training programs for preventing frailty have been mainly developed in person, which have now become difficult to perform due to the coronavirus disease pandemic. It would be worthwhile to explore a feasibility of methods for a remote-based training with information and communications technology (ICT) in the pre-frail/robust older adults living at home.

Methods

We assessed the feasibility of a remote-based training with ICT device in terms of 1) a measurement accuracy and 2) whether it could be used for remote-based training of different intensities. To evaluate a measurement accuracy of the ICT device, we evaluated an inter-rater reliability between a true score and scores obtaining from the ICT device in 20 participants aged 65 years and older. Intraclass correlation was calculated. To evaluate a feasibility of remote-based training interventions of different intensities, we did a parallel, randomized, active controlled trial. Participants aged 65 years or older were randomly allocated to the two 3-month intervention programs with different intensity of exercise with the ICT (i.e., an Exercise-Intensive program and a Light-load exercise program). The primary outcome was 3-month scores of the 30-s chair-stand test (CS-30), which was compared between two groups using mixed models for repeated measures to account for within-person correlations.

Results

The ICT device showed a high intraclass correlation of over 0.99 for all outcomes including CS-30. Between Aug and Oct 2020, 70 participants (36 and 34 in the Exercise-Intensive and Light-load exercise programs, respectively) were randomized. After 3 months of intervention, CS-30 scores and other physical function improved in both groups. Difference in the 3-month CS-30 scores between two programs was found to be 0.08 (95% confidence interval: − 2.64, 2.79; p = 0.955), which was not statistically significant. No harmful incidents, such as falls, occurred in either group.

Conclusion

We showed a remote-based training with ICT device in the older adults living at home was feasible. Further studies are warranted to determine what kind of remote exercise intervention programs is more effective for maintaining a physical performance and, beyond that, preventing frailty.

Trial registration number

UMIN000041616 (05/09/2020) https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=brows&action=brows&recptno=R000047504&type=summary&language=E

Family D DNA polymerase interacts with GINS to promote CMG-helicase in the archaeal replisome

Genomic DNA replication requires replisome assembly. We show here the molecular mechanism by which CMG (GAN-MCM-GINS)-like helicase cooperates with the family D DNA polymerase (PolD) in Thermococcus kodakarensis. The archaeal GINS contains two Gins51 subunits, the C-terminal domain of which (Gins51C) interacts with GAN. We discovered that Gins51C also interacts with the N-terminal domain of PolD's DP1 subunit (DP1N) to connect two PolDs in GINS. The two replicases in the replisome should be responsible for leading- and lagging-strand synthesis, respectively. Crystal structure analysis of the DP1N-Gins51C-GAN ternary complex was provided to understand the structural basis of the connection between the helicase and DNA polymerase. Site-directed mutagenesis analysis supported the interaction mode obtained from the crystal structure. Furthermore, the assembly of helicase and replicase identified in this study is also conserved in Eukarya. PolD enhances the parental strand unwinding via stimulation of ATPase activity of the CMG-complex. This is the first evidence of the functional connection between replicase and helicase in Archaea. These results suggest that the direct interaction of PolD with CMG-helicase is critical for synchronizing strand unwinding and nascent strand synthesis and possibly provide a functional machinery for the effective progression of the replication fork.

DNA polymerase D temporarily connects primase to the CMG-like helicase before interacting with proliferating cell nuclear antigen

The eukaryotic replisome is comprised of three family-B DNA polymerases (Polα, δ and ϵ). Polα forms a stable complex with primase to synthesize short RNA-DNA primers, which are subsequently elongated by Polδ and Polϵ in concert with proliferating cell nuclear antigen (PCNA). In some species of archaea, family-D DNA polymerase (PolD) is the only DNA polymerase essential for cell viability, raising the question of how it alone conducts the bulk of DNA synthesis. We used a hyperthermophilic archaeon, Thermococcus kodakarensis, to demonstrate that PolD connects primase to the archaeal replisome before interacting with PCNA. Whereas PolD stably connects primase to GINS, a component of CMG helicase, cryo-EM analysis indicated a highly flexible PolD–primase complex. A conserved hydrophobic motif at the C-terminus of the DP2 subunit of PolD, a PIP (PCNA-Interacting Peptide) motif, was critical for the interaction with primase. The dissociation of primase was induced by DNA-dependent binding of PCNA to PolD. Point mutations in the alternative PIP-motif of DP2 abrogated the molecular switching that converts the archaeal replicase from de novo to processive synthesis mode.

Two conformations of DNA polymerase D-PCNA-DNA, an archaeal replisome complex, revealed by cryo-electron microscopy

BACKGROUND

DNA polymerase D (PolD) is the representative member of the D family of DNA polymerases. It is an archaea-specific DNA polymerase required for replication and unrelated to other known DNA polymerases. PolD consists of a heterodimer of two subunits, DP1 and DP2, which contain catalytic sites for 3'-5' editing exonuclease and DNA polymerase activities, respectively, with both proteins being mutually required for the full activities of each enzyme. However, the processivity of the replicase holoenzyme has additionally been shown to be enhanced by the clamp molecule proliferating cell nuclear antigen (PCNA), making it crucial to elucidate the interaction between PolD and PCNA on a structural level for a full understanding of its functional relevance. We present here the 3D structure of a PolD-PCNA-DNA complex from Thermococcus kodakarensis using single-particle cryo-electron microscopy (EM).

RESULTS

Two distinct forms of the PolD-PCNA-DNA complex were identified by 3D classification analysis. Fitting the reported crystal structures of truncated forms of DP1 and DP2 from Pyrococcus abyssi onto our EM map showed the 3D atomic structural model of PolD-PCNA-DNA. In addition to the canonical interaction between PCNA and PolD via PIP (PCNA-interacting protein)-box motif, we found a new contact point consisting of a glutamate residue at position 171 in a β-hairpin of PCNA, which mediates interactions with DP1 and DP2. The DNA synthesis activity of a mutant PolD with disruption of the E171-mediated PCNA interaction was not stimulated by PCNA in vitro.

CONCLUSIONS

Based on our analyses, we propose that glutamate residues at position 171 in each subunit of the PCNA homotrimer ring can function as hooks to lock PolD conformation on PCNA for conversion of its activity. This hook function of the clamp molecule may be conserved in the three domains of life.

Room-Temperature Low-Field Colossal Magnetoresistance in Double-Perovskite Manganite

We have discovered room-temperature low-field colossal magnetoresistance (CMR) in an A-site ordered NdBaMn_{2}O_{6} crystal. The resistance changes more than 2 orders of magnitude at a magnetic field lower than 2 T near 300 K. When the temperature and magnetic field sweep from an insulating (metallic) phase to a metallic (insulating) phase, the insulating (metallic) conduction changes to the metallic (insulating) conduction within 1 K and 0.5 T, respectively. The CMR is ascribed to the melting of the charge and orbital ordering. The entropy change which is estimated from the B-T phase diagram is smaller than what is expected for the charge and orbital ordering. The suppression of the entropy change is attributable to the loss of the short-range ferromagnetic fluctuation of Mn spin moments, which is an important key of the high temperature and low magnetic field CMR effect.

Replication protein A complex in Thermococcus kodakarensis interacts with DNA polymerases and helps their effective strand synthesis

Replication protein A (RPA) is an essential component of DNA metabolic processes. RPA binds to single-stranded DNA (ssDNA) and interacts with multiple DNA-binding proteins. In this study, we showed that two DNA polymerases, PolB and PolD, from the hyperthermophilic archaeon Thermococcus kodakarensis interact directly with RPA in vitro. RPA was expected to play a role in resolving the secondary structure, which may stop the DNA synthesis reaction, in the template ssDNA. Our in vitro DNA synthesis assay showed that the pausing was resolved by RPA for both PolB and PolD. These results supported the fact that RPA interacts with DNA polymerases as a member of the replisome and is involved in the normal progression of DNA replication forks.

Elucidating functions of DP1 and DP2 subunits from the Thermococcus kodakarensis family D DNA polymerase

DNA polymerase D (PolD), originally discovered in Pyrococcus furiosus, has no sequence homology with any other DNA polymerase family. Genes encoding PolD are found in most of archaea, except for those archaea in the Crenarchaeota phylum. PolD is composed of two proteins: DP1 and DP2. To date, the 3D structure of the PolD heteromeric complex is yet to be determined. In this study, we established a method that prepared highly purified PolD from Thermococcus kodakarensis, and purified DP1 and DP2 proteins formed a stable complex in solution. An intrinsically disordered region was identified in the N-terminal region of DP1, but the static light scattering analysis provided a reasonable molecular weight of DP1. In addition, PolD forms as a complex of DP1 and DP2 in a 1:1 ratio. Electron microscope single particle analysis supported this composition of PolD. Both proteins play an important role in DNA synthesis activity and in 3'-5' degradation activity. DP1 has extremely low affinity for DNA, while DP2 is mainly responsible for DNA binding. Our work will provide insight and the means to further understand PolD structure and the molecular mechanism of this archaea-specific DNA polymerase.

Two Family B DNA Polymerases From Aeropyrum pernix, Based on Revised Translational Frames

Living organisms are divided into three domains, Bacteria, Eukarya, and Archaea. Comparative studies in the three domains have provided useful information to understand the evolution of the DNA replication machinery. DNA polymerase is the central enzyme of DNA replication. The presence of multiple family B DNA polymerases is unique in Crenarchaeota, as compared with other archaeal phyla, which have a single enzyme each for family B (PolB) and family D (PolD). We analyzed PolB1 and PolB3 in the hyperthermophilic crenarchaeon, Aeropyrum pernix, and found that they are larger proteins than those predicted from the coding regions in our previous study and from public database annotations. The recombinant larger PolBs exhibited the same DNA polymerase activities as previously reported. However, the larger PolB3 showed remarkably higher thermostability, which made this enzyme applicable to PCR. In addition, the high tolerance to salt and heparin suggests that PolB3 will be useful for amplification from the samples with contaminants, and therefore it has a great potential for diagnostic use in the medical and environmental field.

The Cdc45/RecJ-like protein forms a complex with GINS and MCM, and is important for DNA replication in Thermococcus kodakarensis

The archaeal minichromosome maintenance (MCM) has DNA helicase activity, which is stimulated by GINS in several archaea. In the eukaryotic replicative helicase complex, Cdc45 forms a complex with MCM and GINS, named as CMG (Cdc45-MCM-GINS). Cdc45 shares sequence similarity with bacterial RecJ. A Cdc45/RecJ-like protein from Thermococcus kodakarensis shows a bacterial RecJ-like exonuclease activity, which is stimulated by GINS in vitro. Therefore, this archaeal Cdc45/RecJ is designated as GAN, from GINS-associated nuclease. In this study, we identified the CMG-like complex in T. kodakarensis cells. The GAN·GINS complex stimulated the MCM helicase, but MCM did not affect the nuclease activity of GAN in vitro. The gene disruption analysis showed that GAN was non-essential for its viability but the Δgan mutant did not grow at 93°C. Furthermore, the Δgan mutant showed a clear retardation in growth as compared with the parent cells under optimal conditions at 85°C. These deficiencies were recovered by introducing the gan gene encoding the nuclease deficient GAN protein back to the genome. These results suggest that the replicative helicase complex without GAN may become unstable and ineffective in replication fork progression. The nuclease activity of GAN is not related to the growth defects of the Δgan mutant cells.

Atomic structure of an archaeal GAN suggests its dual roles as an exonuclease in DNA repair and a CMG component in DNA replication

In eukaryotic DNA replication initiation, hexameric MCM (mini-chromosome maintenance) unwinds the template double-stranded DNA to form the replication fork. MCM is activated by two proteins, Cdc45 and GINS, which constitute the ‘CMG’ unwindosome complex together with the MCM core. The archaeal DNA replication system is quite similar to that of eukaryotes, but only limited knowledge about the DNA unwinding mechanism is available, from a structural point of view. Here, we describe the crystal structure of an archaeal GAN (GINS-associated nuclease) from Thermococcus kodakaraensis, the homolog of eukaryotic Cdc45, in both the free form and the complex with the C-terminal domain of the cognate Gins51 subunit (Gins51C). This first archaeal GAN structure exhibits a unique, ‘hybrid’ structure between the bacterial RecJ and the eukaryotic Cdc45. GAN possesses the conserved DHH and DHH1 domains responsible for the exonuclease activity, and an inserted CID (CMG interacting domain)-like domain structurally comparable to that in Cdc45, suggesting its dual roles as an exonuclease in DNA repair and a CMG component in DNA replication. A structural comparison of the GAN–Gins51C complex with the GINS tetramer suggests that GINS uses the mobile Gins51C as a hook to bind GAN for CMG formation.

Nontumorous perfusion abnormalities of liver parenchyma adjacent to the falciform ligament as revealed by angiographic helical CT and angiography

Purpose: To investigate nontumorous abnormalities in the liver around the falciform ligament as revealed by arteriography and helical CT arterial portography (CTAP) and helical CT during hepatic arteriography (CTHA).

Material and Methods: One hundred and seventeen patients simultaneously underwent hepatic arteriography and CTAP and CTHA of the common hepatic artery. The number, size, and shape of nontumorous defects of portal perfusion in the liver adjacent to the falciform ligament on CTAP as well as the nontumorous contrast enhancement in the same area on CTHA were determined. In 1 case, in which nontumorous enhancement was observed on CTHA, selective arteriography from the gastric arteries was performed.

Results: On CTAP a nontumorous area of decreased portal perfusion of the liver around the falciform ligament was detected in 18 (15.4%) of the 117 patients, while nontumorous enhancement on CTHA was seen in 7 (6.0%). In 4 patients, both of these nontumorous abnormalities were observed. In the patient undergoing selective gastric arteriography, nonportal venous inflow to the liver in the direction to the liver adjacent to the falciform ligament was seen.

Conclusion: One cause of nontumorous vascular abnormalities adjacent to the falciform ligament as shown on angiographic helical CT is aberrant gastric venous inflow to this region.

Amyloid-Producing Odontogenic Tumors of the Facial Skin in Three Cats

Amyloid-producing odontogenic tumors (APOTs) of the facial skin were diagnosed in 3 domestic cats. The neoplasms had the histopathological characteristics of the odontogenic tumor. The neoplastic cells were present in irregular islands, strands, and sheets. The peripheral neoplastic cells of the islands and strands were arranged in a palisading fashion, while the central cells were polyhedral to stellate and randomly arranged. Multiple spherules of homogeneous eosinophilic material were closely apposed to the neoplastic epithelial cells. The spherules stained with Congo red and produced an apple green birefringence under polarization microscopy, indicative of amyloid. Immunohistochemically, amyloid materials of the neoplasms reacted with polyclonal antibodies for ameloblastin, amelogenin, and sheathlin antibodies. Neoplastic epithelial cells also reacted with antiameloblastin, amelogenin, and sheathlin antibodies, with varied intensity. The histopathological and immunohistochemical characteristics of dermal neoplasms of the 3 cats were analogous to those of APOTs reported in the dog and the cat.

T-Cell Lymphoma with Eosinophilic Infiltration Involving the Intestinal Tract in 11 Dogs

Among the intestinal tumors of hematopoietic cell origin, lymphoma is the most common in the dog. Herein, we characterized the clinical and pathologic features of 11 dogs (average age, 10.6 ± 2.5 years) with T-cell lymphoma of the intestinal tract with eosinophil infiltrates. No sex predominance was apparent. All had localized tumor masses in the small intestine. Grossly, the intestinal wall was thickened, and the lumen of the affected intestine was usually narrowed. Microscopically, we observed transmural diffuse invasion of round to pleomorphic tumor cells. Tumor cells showed varying morphology, from scanty to abundant cytoplasm, and round to ovoid nuclei with scattered to dense chromatin. In seven of the dogs, tumor cells had infiltrated into the epithelium. All showed infiltration of eosinophils and all 11 tumors had a T-cell phenotype (CD3+,CD79-). Only one tumor stained positive for the mast cell marker c-kit and none was positive for mast cell tryptase. We did not observe ultrastructurally apparent granules in any of the tumor cells. These results suggest that, in dogs, T-cell lymphomas of intestinal origin resemble mast cell tumors of intestinal origin with respect to cell structure and eosinophil infiltration. Therefore, in the absence of epitheliotropism, it is difficult to confirm the differential diagnosis without immunostaining for mast cell and lymphocyte markers, including mast cell tryptase, c-kit, CD3, and CD79.

Mast Cell Tumors of the Gastrointestinal Tract in 39 Dogs

Mast cell tumors (MCTs) of gastrointestinal origin that had been surgically removed from 39 dogs were examined to evaluate their pathologic features. Miniature breeds, especially Maltese, were most frequently affected. The average age of affected dogs was 9.7 ± 2.6 years. No sex difference was apparent. The most frequently affected sites were in the upper digestive tract, and the prognosis was very poor. Grossly, the gastrointestinal wall was prominently thickened, and the lumen of the affected gut was usually narrowed. Microscopically, there was diffuse transmural invasion of round to pleomorphic tumor cells. Tumor cells had moderate to abundant cytoplasm, round to ovoid nuclei with scattered chromatin, and mitotic figures. Fibrous stroma was observed in about half of the tumors. There was variable infiltration of eosinophils. In all tumors, cytoplasmic granules showed weak metachromasia, but the number of granules was very small. Immunohistochemical staining for c-kit and mast cell tryptase was positive in 77% and 62% of tumors, respectively. All tumors were positive for at least two of these markers. Immunohistochemical staining for p53 was positive in 13% of the tumors. Reactivity for staining markers and p53 was unrelated to cell pleomorphism, vessel invasion, or survival time. Gastrointestinal MCTs have histologic and immunohistochemical features completely different from those of other primary or metastatic gastrointestinal tumors. The combination of immunostaining for mast cell tryptase and c-kit and histochemical staining for metachromasia appears to be a powerful tool for the diagnosis of gastrointestinal MCTs.

PCNA is involved in the EndoQ-mediated DNA repair process in Thermococcales

To maintain genome integrity for transfer to their offspring, and to maintain order in cellular processes, all living organisms have DNA repair systems. Besides the well-conserved DNA repair machineries, organisms thriving in extreme environments are expected to have developed efficient repair systems. We recently discovered a novel endonuclease, which cleaves the 5′ side of deoxyinosine, from the hyperthermophilic archaeon, Pyrococcus furiosus. The novel endonuclease, designated as Endonulcease Q (EndoQ), recognizes uracil, abasic site and xanthine, as well as hypoxanthine, and cuts the phosphodiester bond at their 5′ sides. To understand the functional process involving EndoQ, we searched for interacting partners of EndoQ and identified Proliferating Cell Nuclear Angigen (PCNA). The EndoQ activity was clearly enhanced by addition of PCNA in vitro. The physical interaction between the two proteins through a PIP-motif of EndoQ and the toroidal structure of PCNA are critical for the stimulation of the endonuclease activity. These findings provide us a clue to elucidate a unique DNA repair system in Archaea.

Identification of a mismatch-specific endonuclease in hyperthermophilic Archaea

The common mismatch repair system processed by MutS and MutL and their homologs was identified in Bacteria and Eukarya. However, no evidence of a functional MutS/L homolog has been reported for archaeal organisms, and it is not known whether the mismatch repair system is conserved in Archaea. Here, we describe an endonuclease that cleaves double-stranded DNA containing a mismatched base pair, from the hyperthermophilic archaeon Pyrococcus furiosus The corresponding gene revealed that the activity originates from PF0012, and we named this enzyme Endonuclease MS (EndoMS) as the mismatch-specific Endonuclease. The sequence similarity suggested that EndoMS is the ortholog of NucS isolated from Pyrococcus abyssi, published previously. Biochemical characterizations of the EndoMS homolog from Thermococcus kodakarensis clearly showed that EndoMS specifically cleaves both strands of double-stranded DNA into 5'-protruding forms, with the mismatched base pair in the central position. EndoMS cleaves G/T, G/G, T/T, T/C and A/G mismatches, with a more preference for G/T, G/G and T/T, but has very little or no effect on C/C, A/C and A/A mismatches. The discovery of this endonuclease suggests the existence of a novel mismatch repair process, initiated by the double-strand break generated by the EndoMS endonuclease, in Archaea and some Bacteria.

A longer finger-subdomain of family A DNA polymerases found by metagenomic analysis strengthens DNA binding and primer extension abilities

The family A DNA polymerases from thermophilic bacteria are useful for PCR. The DNA polymerase from Thermus aquaticus (Taq polymerase) was the original enzyme used when practical PCR was developed, and it has remained the standard enzyme for PCR to date. Knowledge gained from structure-function relationship studies of Taq polymerase is applicable to create PCR enzymes with enhanced performance. We collected the deduced amino acid sequences of the regions from motif A to motif C in the family A DNA polymerases from metagenomic sequence data, obtained by sequencing DNAs from microorganisms isolated from various hot spring areas in Japan. The corresponding regions of the polA gene for Taq polymerase were substituted with the metagenomic DNA gene fragments, and various chimeric DNA polymerases were prepared. Based on the properties of these chimeric enzymes and their sequences, we found an insertion sequence that affects the primer extension ability of the family A DNA polymerases. The insertion sequence is located in the finger subdomain, and it may enhance the affinity of the enzyme to DNA. Mutant Taq polymerases with the corresponding 9 amino acid insertion displayed enhanced PCR performance.

A novel endonuclease that may be responsible for damaged DNA base repair in Pyrococcus furiosus

DNA is constantly damaged by endogenous and environmental influences. Deaminated adenine (hypoxanthine) tends to pair with cytosine and leads to the A:T→G:C transition mutation during DNA replication. Endonuclease V (EndoV) hydrolyzes the second phosphodiester bond 3′ from deoxyinosine in the DNA strand, and was considered to be responsible for hypoxanthine excision repair. However, the downstream pathway after EndoV cleavage remained unclear. The activity to cleave the phosphodiester bond 5′ from deoxyinosine was detected in a Pyrococcus furiosus cell extract. The protein encoded by PF1551, obtained from the mass spectrometry analysis of the purified fraction, exhibited the corresponding cleavage activity. A putative homolog from Thermococcus kodakarensis (TK0887) showed the same activity. Further biochemical analyses revealed that the purified PF1551 and TK0887 proteins recognize uracil, xanthine and the AP site, in addition to hypoxanthine. We named this endonuclease Endonuclease Q (EndoQ), as it may be involved in damaged base repair in the Thermococcals of Archaea.

Mutant Taq DNA polymerases with improved elongation ability as a useful reagent for genetic engineering

DNA polymerases are widely used for DNA manipulation in vitro, including DNA cloning, sequencing, DNA labeling, mutagenesis, and other experiments. Thermostable DNA polymerases are especially useful and became quite valuable after the development of PCR technology. A DNA polymerase from Thermus aquaticus (Taq polymerase) is the most famous DNA polymerase as a PCR enzyme, and has been widely used all over the world. In this study, the gene fragments of the family A DNA polymerases were amplified by PCR from the DNAs from microorganisms within environmental soil samples, using a primer set for the two conserved regions. The corresponding region of the pol gene for Taq polymerase was substituted with the amplified gene fragments, and various chimeric DNA polymerases were prepared. Based on the properties of these chimeric enzymes and their sequences, two residues, E742 and A743, in Taq polymerase were found to be critical for its elongation ability. Taq polymerases with mutations at 742 and 743 actually showed higher DNA affinity and faster primer extension ability. These factors also affected the PCR performance of the DNA polymerase, and improved PCR results were observed with the mutant Taq polymerase.

Multiple interactions of the intrinsically disordered region between the helicase and nuclease domains of the archaeal Hef protein

Hef is an archaeal protein that probably functions mainly in stalled replication fork repair. The presence of an unstructured region was predicted between the two distinct domains of the Hef protein. We analyzed the interdomain region of Thermococcus kodakarensis Hef and demonstrated its disordered structure by CD, NMR, and high speed atomic force microscopy (AFM). To investigate the functions of this intrinsically disordered region (IDR), we screened for proteins interacting with the IDR of Hef by a yeast two-hybrid method, and 10 candidate proteins were obtained. We found that PCNA1 and a RecJ-like protein specifically bind to the IDR in vitro. These results suggested that the Hef protein interacts with several different proteins that work together in the pathways downstream from stalled replication fork repair by converting the IDR structure depending on the partner protein.

Diagnostic performance of percutaneous lung biopsy using automated biopsy needles under CT-fluoroscopic guidance for ground-glass opacity lesions

OBJECTIVE

The goal of our study was to evaluate the diagnostic performance of percutaneous lung biopsy under CT-fluoroscopic guidance for ground-glass opacity (GGO) lesions.

METHODS

85 percutaneous needle lung biopsies were performed in 73 patients. Specimens were obtained by core biopsy utilising an automated cutting needle and were evaluated histologically. Final diagnosis was confirmed by independent surgical pathology, independent culture results or clinical follow-up.

RESULTS

Rates of adequate specimens obtained and of precise diagnosis by needle biopsy were 92.9% (79/85) and 90.6% (77/85) of evaluated lung lesions, respectively. Precise diagnosis was achieved in 87.1% (27/31) of lesions ≤10 mm in diameter, 90.0% (36/40) of lesions >10 mm to ≤20 mm and 100.0% (14/14) of lesions >20 mm. Precision in diagnosing GGO lesions according to the GGO component was 73.9% (17/23) for pure GGO lesions and 96.8% (60/62) for part-solid GGO lesions. Obtaining a precise diagnosis did not differ significantly according to the lesion size (p=0.3840), but differences were significant according to the GGO component (p=0.0047). Malignancy was accurately diagnosed in 35 of 36 malignant lesions for which surgery was later performed. The specific cell type determined from specimens obtained by needle biopsy was exactly the same as the final histological diagnosis obtained after surgery in 20 lesions.

CONCLUSION

Tissue-core lung biopsy under CT-fluoroscopic guidance for a GGO lesion provides a high degree of diagnostic accuracy but is less reliable for determining the specific cell type.

ADVANCES IN KNOWLEDGE

Percutaneous lung biopsy under CT-fluoroscopic guidance for GGO is useful in differentiating malignancy.

Comparative analyses of the two proliferating cell nuclear antigens from the hyperthermophilic archaeon, Thermococcus kodakarensis

The DNA sliding clamp is a multifunctional protein involved in cellular DNA transactions. In Archaea and Eukaryota, proliferating cell nuclear antigen (PCNA) is the sliding clamp. The ring-shaped PCNA encircles double-stranded DNA within its central hole and tethers other proteins on DNA. The majority of Crenarchaeota, a subdomain of Archaea, have multiple PCNA homologues, and they are capable of forming heterotrimeric rings for their functions. In contrast, most organisms in Euryarchaeota, the other major subdomain, have a single PCNA forming a homotrimeric ring structure. Among the Euryarchaeota whose genome is sequenced, Thermococcus kodakarensis is the only species with two genes encoding PCNA homologues on its genome. We cloned the two genes from the T. kodakarensis genome, and the gene products, PCNA1 and PCNA2, were characterized. PCNA1 stimulated the DNA synthesis reactions of the two DNA polymerases, PolB and PolD, from T. kodakarensis in vitro. PCNA2, however, only had an effect on PolB. We were able to disrupt the gene for PCNA2, whereas gene disruption for PCNA1 was not possible, suggesting that PCNA1 is essential for DNA replication. The sensitivities of the Δpcna2 mutant strain to ultraviolet irradiation (UV), methyl methanesulfonate (MMS) and mitomycin C (MMC) were indistinguishable from those of the wild-type strain.

Obesity and cardiac autonomic nerve activity in healthy children: Results of the toyama birth cohort study

OBJECTIVES

To determine the relationship between obesity and cardiac autonomic nerve activity in healthy children.

METHODS

16 healthy male children comprising of 9 nonobese and 7 obese subjects (body mass index > 19.1 kg/m(2)) aged 8-9 years were selected. Electrocardiograms were measured for 10 min. under controlled ventilation (0.25 Hz) in the supine position. Consecutive 256-second RR interval data were transformed by the Fast Fourier Transform method into power spectral data. Very low frequency (VLF; 0.003-0.04 Hz), low frequency (LF; 0.04-0.15Hz), high frequency (HF; 0.15-0.40Hz), and total power (TP; 0.003-0.40Hz) were calculated and transformed into a natural logarithm (In). Normalized units (nu) were also calculated as follows: LFnu=LF/(TP-VLF)x100. HFnu=HF/(TP-VLF)x100. Low/high-frequency ratio (LHR) was calculated as LF divided by HF. Unpaired t test was performed to compare the 2 groups.

RESULTS

TP In and HFnu, reflecting cardiac parasympathetic nerve activity, in obese children were significantly lower than those in nonobese children. In contrast, LFnu and LHF, reflecting cardiac sympathetic nerve activity, in obese children were significantly higher than those in nonobese children.

CONCLUSIONS

These findings suggest that obese children have higher sympathetic nerve activity and lower parasympathetic nerve activity than nonobese children.

Influence of Behavioral and Environmental Factors on the Development of Obesity in Three-year-old Children -A Case-Control Study Based on Toyama Study-

Obesity in children seems to be a risk factor for chronic diseases in adulthood. From the viewpoint of preventive medicine, factors influencing the development of obese children should be removed early in life.The purpose of this study was to the elucidate relationship between obesity in 3-year-old children and both behavioral and environmental factors by conducting a case-control study. Subjects were selected from the Toyama study. Matched-pair comparisons were performed between obese children whose Kaup's index was 18 or more (N=117) and control children (N=234) . Multivariate stepwised logistic regression analysis also applied to assess influence of confounding factors.The results indicated that the following 6 factors significantly influenced the development of obese 3-year-old children in exact Fisher's method analysis (p<0.05): person other than the mother responsible for taking care of the child, short sleep duration (9 hours or less), physical inactivity, eating snacks irregularly, overweight father (BMI≥24), and overweight mother (BMI≥24). For both sexes, after adjusting for confounders by multivariate stepwise logistic analysis, overweight mother (OR 2.54, 95 % CI 1.64-3.95), birth overweight (birth weight≥3,500g; OR 1.76, 95 % CI 1.15-2.69), the mother not responsible for taking care of the child (OR 1.65, 95% CI 1.10-2.48), overweight father (OR 1.62, 95%CI 1.09-2.40), eating snacks irregularly (OR 1.56, 95% CI 1.04-2.33), and gender (female;OR 0.51, 95% CI 0.34-0.77) had significant relationships with obesity in childhood. For boys, overweight mother (OR 2.53, 95 % CI 1.47-4.35), birth overweight (OR 2.03, 95%CI 1.22-3.39), eating snacks irregularly (OR 1.94, 95 %CI 1.19-3.18), and birth month (36-41 months; OR 0.47, 95 % CI 0.23-0.96) had significant relationships. For girls, overweight mother (OR 2.62, 1.28-5.35), and short sleep duration (OR 2.24, 1.11-4.52) had significant relationships. In neither Fisher's exact method nor multivariate logistic models, time to wake up, bedtime, duration of playing outdoors, regularity of meals, care about salty food, or frequency of eating snacks had significant relations with obesity in 3-year-old children (p<0.05).

Search for antihelium with the BESS-Polar spectrometer

In two long-duration balloon flights over Antarctica, the Balloon-borne Experiment with a Superconducting Spectrometer (BESS) collaboration has searched for antihelium in the cosmic radiation with the highest sensitivity reported. BESS-Polar I flew in 2004, observing for 8.5 days. BESS-Polar II flew in 2007-2008, observing for 24.5 days. No antihelium candidate was found in BESS-Polar I data among 8.4×10(6) |Z|=2 nuclei from 1.0 to 20 GV or in BESS-Polar II data among 4.0×10(7) |Z|=2 nuclei from 1.0 to 14 GV. Assuming antihelium to have the same spectral shape as helium, a 95% confidence upper limit to the possible abundance of antihelium relative to helium of 6.9×10(-8)} was determined combining all BESS data, including the two BESS-Polar flights. With no assumed antihelium spectrum and a weighted average of the lowest antihelium efficiencies for each flight, an upper limit of 1.0×10(-7) from 1.6 to 14 GV was determined for the combined BESS-Polar data. Under both antihelium spectral assumptions, these are the lowest limits obtained to date.

Measurement of the cosmic-ray antiproton spectrum at solar minimum with a long-duration balloon flight over antarctica

The energy spectrum of cosmic-ray antiprotons (p's) from 0.17 to 3.5 GeV has been measured using 7886 p's detected by BESS-Polar II during a long-duration flight over Antarctica near solar minimum in December 2007 and January 2008. This shows good consistency with secondary p calculations. Cosmologically primary p's have been investigated by comparing measured and calculated p spectra. BESS-Polar II data show no evidence of primary p's from the evaporation of primordial black holes.

Comparison of fully automated and semi-automated biopsy needles for lung biopsy under CT fluoroscopic guidance

OBJECTIVE

The aim of this study was to compare two different automated biopsy needles, a fully automated biopsy needle (Monopty; Bard, Covington, GA) and a semi-automated biopsy needle (Temno; Bauer Medical, Clearwater, FL), for lung biopsy.

METHODS

50 consecutive percutaneous lung biopsies using the Monopty needle between June 2006 and January 2007 and 66 consecutive lung biopsies for 1 nodule in each session using the Temno needle between February 2007 and August 2008 were performed under CT fluoroscopic guidance followed by histopathological evaluation.

RESULTS

In 42/50 lung biopsies performed with the Monopty needle and 54/66 lung biopsies performed with the Temno needle, the final diagnosis was confirmed by independent surgical pathological findings or clinical follow-up. Sufficient samples for histopathological evaluation were obtained in all 50 (100%) biopsies using the Monopty needle and in 55 (83.3%) of the 66 biopsies using the Temno needle (p<0.01). Accurate diagnosis was achieved in 41 (97.6%) of 42 biopsies using the Monopty needle and in 45 (83.3%) of 54 biopsies using the Temno needle (p=0.04). Biopsy-induced complications were pneumothorax, haemoptysis and haemothorax in 44.0%, 10.0% and 6.0% of biopsies, respectively, using the Monopty needle and in 48.3%, 8.3% and 3.3%, respectively, using the Temno needle.

CONCLUSION

There is a possibility that a fully automated biopsy needle such as the Monopty is more useful for CT scan-guided lung biopsy than semi-automated biopsy needles.

Hepatic artery-targeting guidewire technique during transjugular intrahepatic portosystemic shunt

OBJECTIVE

This study evaluated the feasibility and safety of the transjugular intrahepatic portosystemic shunt (TIPS) procedure using the hepatic artery-targeting guidewire technique for the puncture step.

METHODS

We retrospectively reviewed 11 consecutive patients (5 men and 6 women, aged 46-76 years (mean 64 years)) with portal hypertension in whom the TIPS procedure was performed. As the first step in the TIPS procedure in all cases, a micro-guidewire was inserted into the hepatic arterial branch accompanying the portal venous branch through a microcatheter coaxially advanced from a 5-French catheter positioned in the coeliac or common hepatic artery. At the puncture step, the tip of the metallic cannula was aimed 1 cm posterior to the distal part of this micro-guidewire, after which the TIPS procedure was performed. Success rate, number of punctures and complications were evaluated.

RESULTS

The TIPS procedure was successfully performed in all 11 patients. The mean number of punctures until success in entering the targeted portal venous branch was 5 (range 1-14). In 3 patients (27%), the right portal venous branch was entered at the first puncture attempt. The hepatic artery was punctured once in one patient and the bile duct was punctured once in another patient. No serious procedure-induced complications occurred.

CONCLUSION

The TIPS procedure can be accomplished safely, precisely and relatively easily using the hepatic artery-targeting guidewire technique.

Embolisation of the right gastric artery in patients undergoing hepatic arterial infusion chemotherapy using two possible approach routes

We used a retrospective non-randomised study to investigate the clinical effect of selective embolisation of the right gastric artery before hepatic arterial infusion chemotherapy (HAIC) using a port-catheter system. We evaluated whether the hepatic artery or the left gastric artery is the better approach for selecting the right gastric artery. A total of 367 patients (244 men and 123 women; mean age, 64.1 years) with unresectable advanced liver cancer underwent percutaneous implantation of a port-catheter system. In 294 of these patients, right gastric arterial embolisation with microcoils was attempted before placement of the port-catheter system to prevent gastric mucosal lesions. Approach was either through the hepatic artery (175 patients) or through the left gastric artery (119 patients), with success rates in catheterising the right gastric artery of 78.3% and 77.3%, respectively. If the attempt was unsuccessful, the catheter was redirected to the alternative approach, which increased the final success rate to 96.3%. Only seven patients experienced gastroduodenal mucosal lesions acutely after HAIC, as revealed by endoscopy. Embolisation of the right gastric artery is a feasible procedure that can reduce the incidence of gastric mucosal lesions associated with HAIC. Approach through either the hepatic artery or the left gastric artery is equally acceptable.

Cdc6/Orc1 from Pyrococcus furiosus may act as the origin recognition protein and Mcm helicase recruiter

Archaea have one or more Cdc6/Orc1 proteins, which share sequence similarities with eukaryotic Cdc6 and Orc1. These proteins are involved in the initiation process of DNA replication, although their specific function has not been elucidated, except for origin recognition and binding. We showed that the Cdc6/Orc1 protein from the hyperthermophilic archaeon Pyrococcus furiosus specifically binds to the oriC region in the whole genome. However, it remains unclear how this initiator protein specifically recognizes the oriC region and how the Mcm helicase is recruited to oriC. In the current study, we characterized the biochemical properties of Cdc6/Orc1 in P. furiosus. The ATPase activity of the Cdc6/Orc1 protein was completely suppressed by binding to DNA containing the origin recognition box (ORB). Limited proteolysis and DNase I-footprint experiments suggested that the Cdc6/Orc1 protein changes its conformation on the ORB sequence in the presence of ATP. This conformational change may have an unknown, important function in the initiation process. Results from an in vitro recruiting assay indicated that Mcm is recruited onto the oriC region in a Cdc6/Orc1-dependent, but not ATP-dependent, manner. However, some other function is required for the functional loading of this helicase to start the unwinding of the replication fork DNA.

Role of manual aspiration in treating pneumothorax after computed tomography-guided lung biopsy

BACKGROUND

Pneumothorax is the most common complication after computed tomography (CT)-guided lung biopsy. The presence of a pneumothorax per se does not complicate patient management, but an increasing pneumothorax, making chest tube placement necessary, is highly problematic.

PURPOSE

To evaluate the efficacy and limitations of simple aspiration of air from the pleural space to prevent increased pneumothorax and avoid chest tube placement in cases of pneumothorax following CT-guided lung biopsy.

MATERIAL AND METHODS

The subjects of our study were 642 consecutive lung lesions in 594 patients for which percutaneous needle lung biopsies were performed using CT guidance. While patients were on the CT scanner table, percutaneous manual aspiration was performed in all patients with a non-small pneumothorax demonstrated on post-biopsy chest CT images. The frequency of pneumothorax, management of each such case, and factors influencing the incidence of worsening pneumothorax that finally required chest tube placement were evaluated.

RESULTS

Post-biopsy pneumothorax occurred in 243 of 642 (38%) procedures. Of the 243 cases, 112 were treated with manual aspiration immediately after biopsy. In 210 (86.4%), the pneumothorax had resolved completely on follow-up chest radiographs without chest tube placement. Only 33 patients required chest tube placement. Requirement of chest tube insertion significantly increased in parallel with the degree of pneumothorax as shown on post-biopsy CT images. The rate of chest tube insertion was statistically higher in subjects with values for aspirated air above 543 ml.

CONCLUSION

Percutaneous manual aspiration of biopsy-induced pneumothorax performed immediately after biopsy may prevent worsening of pneumothorax and avoid chest tube placement. The amount of aspirated air can be predictive of the requirement for chest tube placement.

Localized melting of duplex DNA by Cdc6/Orc1 at the DNA replication origin in the hyperthermophilic archaeon Pyrococcus furiosus

The initiation step is a key process to regulate the frequency of DNA replication. Although recent studies in Archaea defined the origin of DNA replication (oriC) and the Cdc6/Orc1 homolog as an origin recognition protein, the location and mechanism of duplex opening have remained unclear. We have found that Cdc6/Orc1 binds to oriC and unwinds duplex DNA in the hyperthermophilic archaeon Pyrococcus furiosus, by means of a P1 endonuclease assay. A primer extension analysis further revealed that this localized unwinding occurs in the oriC region at a specific site, which is 12-bp long and rich in adenine and thymine. This site is different from the predicted duplex unwinding element (DUE) that we reported previously. We also discovered that Cdc6/Orc1 induces topological changes in supercoiled oriC DNA, and that this process is dependent on the AAA+ domain. These results indicate that topological alterations of oriC DNA by Cdc6/Orc1 introduce a single-stranded region at the 12-mer site, that could possibly serve as an entry point for Mcm helicase.

Balloon-occluded retrograde transvenous obliteration of a gastric varix via the left inferior phrenic vein

We encountered a patient with a gastric varix that drained through the left inferior phrenic vein, which directly entered the inferior vena cava at the point just inferior to the diaphragm. In this patient, gastrorenal shunt was not seen. Balloon-occluded retrograde transvenous obliteration of the gastric varix was performed, in which 50% glucose and 5% ethanolamine oleate-iopamidol were injected as sclerosing agents while the balloon was inflated in the left inferior phrenic vein. 1 week after the procedure, the disappearance of enhancement in the gastric varix was confirmed on contrast-enhanced multidetector row CT. Furthermore, a significant reduction in the size of the varix was confirmed on endoscopic examination 4 months later.

Redistribution of multiple hepatic arteries into a single hepatic artery to perform repeated hepatic arterial infusion chemotherapy

BACKGROUND

In patients with two or more intrahepatic arteries, multiple intrahepatic arteries should be converted into a single intrahepatic artery before repeated hepatic arterial infusion chemotherapy. However, the number of reports investigating this has been scanty.

PURPOSE

To evaluate the usefulness of the redistribution of multiple hepatic arteries into a single hepatic artery for repeated hepatic arterial infusion chemotherapy (HAIC) through an indwelling port-catheter system for unresectable liver malignancies.

MATERIAL AND METHODS

In 76 patients with unresectable advanced liver cancer, redistribution of multiple hepatic arteries into one hepatic artery was performed prior to port-catheter system implantation. Investigated were distribution in the liver, as evaluated with computed tomography (CT) during arteriography via the port after implantation, and management of cases in which distribution in the entire liver was not achieved.

RESULTS

In 64 patients, good distribution in the entire liver was confirmed on CT arteriography via the port. In the remaining 12 patients, contrast material was heterogeneously distributed. The segments with poor distribution were segments VI, VII, VIII, and I. In the five patients with tumors in segments having poor distribution, the right inferior phrenic artery was successfully embolized and good distribution throughout the entire liver was thereafter achieved in all five.

CONCLUSION

In cases with multiple hepatic arteries, redistribution procedures allow application of repeated HAIC through a single indwelling catheter while maintaining distribution over the entire liver. However, care regarding hepatopetal flow of the right inferior phrenic artery is necessary.

Prophylactic implantation of inferior vena cava filter during endovascular therapies for deep venous thrombosis of the lower extremity: is it necessary?

BACKGROUND

There is strong controversy as to whether to use filters temporarily in the inferior vena cava (IVC) during endovascular therapies for deep venous thrombosis (DVT) in the lower extremity.

PURPOSE

To evaluate the necessity of implantation of a retrievable inferior vena cava filter during treatment of DVT in the lower extremity using various endovascular techniques.

MATERIAL AND METHODS

Studied were all 37 consecutive sessions of endovascular treatments performed in 34 patients with symptomatic lower-limb DVT between April 2001 and October 2006. In all sessions, a Gunther tulip retrievable vena cava filter (GTF) was implanted during the procedures. The degree of trapped thrombus in the filter was evaluated by repeated venocavography.

RESULTS

Implantation of a total of 66 GTFs was successfully performed in 37 sessions. Worsening of or new formation of pulmonary embolism was avoided in all patients. In 20 (54.1%) of the 37 sessions, a trapped thrombus in the filter was observed. In 14, the trapped thrombus was large, filling more than half the height of the filter.

CONCLUSION

Temporary implantation of filters is effective in preventing pulmonary emboli during endovascular treatment of DVT in the lower extremities.

Should balloon-occluded retrograde transvenous obliteration be the first-line interventional radiologic treatment for bleeding duodenal varices? A case report and review of the literature

We report a 78-year-old woman who presented with repeated tarry stools, and having lower duodenal variceal bleeding caused by portal hypertension. Endoscopic therapy had been attempted, but was impossible because the endoscope could not be inserted into the lower duodenum. Thus, the lower duodenal variceal bleeding was treated with balloon-occluded retrograde transvenous obliteration in combination with embolization using microcoils. Complete hemostasis was achieved without complications, and neither the recurrence of varices nor rebleeding has occurred for the last 3 years. A review of the English-language literature reveals only 11 such cases. The world literature is reviewed.

Infusion of 50% glucose solution before injection of ethanolamine oleate during balloon-occluded retrograde transvenous obliteration

The feasibility of infusion of 50% glucose solution before balloon-occluded retrograde transvenous obliteration (BRTO) to occlude collateral vessels draining gastric varices other than gastrorenal shunt was evaluated. In five patients with such collateral vessels, 50% glucose solution was infused from the balloon catheter inflated within the gastrorenal shunt. The degree of collateral vessels had decreased when BRTO was carried out so that sclerotic agents sufficiently occupied the gastric varices in all patients. In three patients, embolization of collateral vessels with coils was unnecessary. There were no complications. In conclusion, retrograde infusion of 50% glucose solution assists in effectively carrying out BRTO.

Infusion of 50% glucose solution before injection of ethanolamine oleate during balloon-occluded retrograde transvenous obliteration

The feasibility of infusion of 50% glucose solution before balloon-occluded retrograde transvenous obliteration (BRTO) to occlude collateral vessels draining gastric varices other than gastrorenal shunt was evaluated. In five patients with such collateral vessels, 50% glucose solution was infused from the balloon catheter inflated within the gastrorenal shunt. The degree of collateral vessels had decreased when BRTO was carried out so that sclerotic agents sufficiently occupied the gastric varices in all patients. In three patients, embolization of collateral vessels with coils was unnecessary. There were no complications. In conclusion, retrograde infusion of 50% glucose solution assists in effectively carrying out BRTO.

Transcatheter arterial embolisation of a ruptured pseudoaneurysm of the lingual artery with n-butyl cyanoacrylate

Pseudoaneurysms can arise due to localized arterial wall disruption, owing to various factors such as inflammation, trauma, neoplasm, or surgical procedures. Once ruptured, bleeding can be life-threatening. Thus, a treatment for pseudoaneurysm is necessary. We describe a case of post-surgical ruptured pseudoaneurysm of the lingual artery that was successfully treated by transcatheter embolisation with n-butyl cyanoacrylate (NCBA).