PirB regulates asymmetries in hippocampal circuitry

Left-right asymmetry is a fundamental feature of higher-order brain structure; however, the molecular basis of brain asymmetry remains unclear. We recently identified structural and functional asymmetries in mouse hippocampal circuitry that result from the asymmetrical distribution of two distinct populations of pyramidal cell synapses that differ in the density of the NMDA receptor subunit GluRε2 (also known as NR2B, GRIN2B or GluN2B). By examining the synaptic distribution of ε2 subunits, we previously found that β2-microglobulin-deficient mice, which lack cell surface expression of the vast majority of major histocompatibility complex class I (MHCI) proteins, do not exhibit circuit asymmetry. In the present study, we conducted electrophysiological and anatomical analyses on the hippocampal circuitry of mice with a knockout of the paired immunoglobulin-like receptor B (PirB), an MHCI receptor. As in β2-microglobulin-deficient mice, the PirB-deficient hippocampus lacked circuit asymmetries. This finding that MHCI loss-of-function mice and PirB knockout mice have identical phenotypes suggests that MHCI signals that produce hippocampal asymmetries are transduced through PirB. Our results provide evidence for a critical role of the MHCI/PirB signaling system in the generation of asymmetries in hippocampal circuitry

Combination of plasma MMPs and PD-1-binding soluble PD-L1 predicts recurrence in gastric cancer and the efficacy of immune checkpoint inhibitors in non-small cell lung cancer

BackgroundThe tumor microenvironment (TME) impacts the therapeutic efficacy of immune checkpoint inhibitors (ICIs). No liquid biomarkers are available to evaluate TME heterogeneity. Here, we investigated the clinical significance of PD-1-binding soluble PD-L1 (bsPD-L1) in gastric cancer (GC) patients and non-small cell lung cancer (NSCLC) patients treated with PD-1/PD-L1 blockade.MethodsWe examined bsPD-L1, matrix metalloproteinases (MMPs), and IFN-γ levels in plasma samples from GC patients (n = 117) prior to surgery and NSCLC patients (n = 72) prior to and 2 months after ICI treatment. We also examined extracellular matrix (ECM) integrity, PD-L1 expression, and T cell infiltration in tumor tissues from 25 GC patients by Elastica Masson-Goldner staining and immunohistochemical staining for PD-L1 and CD3, respectively.ResultsbsPD-L1 was detected in 17/117 GC patients and 16/72 NSCLC patients. bsPD-L1 showed strong or moderate correlations with plasma MMP13 or MMP3 levels, respectively, in both GC and NSCLC patients. bsPD-L1 expression in GC was associated with IFN-γ levels and intra-tumoral T cell infiltration, whereas MMP13 levels were associated with loss of ECM integrity, allowing tumor cells to access blood vessels. Plasma MMP3 and MMP13 levels were altered during ICI treatment. Combined bsPD-L1 and MMP status had higher predictive accuracy to identify two patient groups with favorable and poor prognosis than tumor PD-L1 expression: bsPD-L1+MMP13high in GC and bsPD-L1+(MMP3 and MMP13)increased in NSCLC were associated with poor prognosis, whereas bsPD-L1+MMP13low in GC and bsPD-L1+(MMP3 or MMP13)decreased in NSCLC were associated with favorable prognosis.ConclusionPlasma bsPD-L1 and MMP13 levels indicate T cell response and loss of ECM integrity, respectively, in the TME. The combination of bsPD-L1 and MMPs may represent a non-invasive tool to predict recurrence in GC and the efficacy of ICIs in NSCLC

Photoreactions of Sc3N@C80 with Disilirane, Silirane, and Digermirane: A Photochemical Method to Separate Ih and D5h Isomers

Under photoirradiation, Sc3N@Ih-C80 reacted readily with disilirane 1, silirane 4, and digermirane 7 to afford the corresponding 1:1 adducts, whereas Sc3N@D5h-C80 was recovered without producing those adducts. Based on these results, we described a novel method for the exclusive separation of Ih and D5h isomers of Sc3N@C80. The method includes three procedures: selective derivatization of Sc3N@Ih-C80 using 1, 4, and 7, facile HPLC separation of pristine Sc3N@D5h-C80 and Sc3N@Ih-C80 derivatives, and thermolysis of Sc3N@Ih-C80 derivatives to collect pristine Sc3N@Ih-C80. In addition, laser flash photolysis experiments were conducted to elucidate the reaction mechanism. Decay of the transient absorption of 3Sc3N@Ih-C80* was observed to be enhanced in the presence of 1, indicating the quenching process. When Sc3N@D5h-C80 was used, the transient absorption was much less intensive. Therefore, the quenching of 3Sc3N@D5h-C80* by 1 could not be confirmed. Furthermore, we applied time-dependent density functional theory (TD-DFT) calculations of the photoexcited states of Sc3N@C80 to obtain insights into the reaction mechanism

Lymphokine-activated killer cell transplantation after anti-cancer treatment in two aged cats

Immunotherapy improves both survival and remission rates after cancer surgery in humans, but its veterinary use has been limited. We determined the safety and feasibility of lymphokine-activated killer (LAK) cell transplantation in two aged cats that had undergone surgery for malignancy. Case 1 involved an 18-year-old male Japanese domestic cat. The cat exhibited appetite loss and poor physical activity after surgical excision of oral squamous cell carcinoma followed by four sessions of radiotherapy, and the owner strongly requested immunotherapy for preventing further deterioration in the animal’s quality of life (QOL). We subsequently administered LAK cells three times during a 2-month period. Case 2 involved a 20-year-old female Japanese domestic cat who had undergone mammectomy after a diagnosis of breast adenocarcinoma. The owner strongly requested immunotherapy for QOL maintenance. We administered LAK cells four times over a period of 5 months. Autologous peripheral blood mononuclear cells (PBMCs) fractionated using density gradient centrifugation were cultured in media containing a high concentration of interleukin-2 and supplemented with 2.5% foetal calf serum. The derived LAK cells were centrifuged, suspended in 10 ml of saline containing 1% of the subject’s own blood, and infused into the cephalic vein of the cats over 30 mins. The composition ratios of CD3, CD4, CD8, and CD21 were evaluated by flow cytometry. Bacterial culture and endotoxin testing for a sample of LAK cells showed negative results in both cases. The leukocyte and erythrocyte counts and the body temperature were assessed on days 7, 14 and 21 after the transfusion. No abnormal signs were observed in either case, which confirmed the safety of the procedure. QOL scores showed no significant changes after the treatment, and the body temperature remained steady throughout the treatment. The findings from these cases suggest that transplantation of LAK cells derived from PBMCs may be safe and feasible for use in cats, regardless of their age

Lymphokine-activated killer cell transplantation after anti-cancer treatment in two aged cats

Immunotherapy improves both survival and remission rates after cancer surgery in humans, but its veterinary use has been limited. We determined the safety and feasibility of lymphokine-activated killer (LAK) cell transplantation in two aged cats that had undergone surgery for malignancy. Case 1 involved an 18-year-old male Japanese domestic cat. The cat exhibited appetite loss and poor physical activity after the surgical excision of oral squamous cell carcinoma followed by four sessions of radiotherapy, and the owner strongly requested immunotherapy for preventing further deterioration in the animal’s quality of life (QOL). We subsequently administered LAK cells three times during a 2-month period. Case 2 involved a 20-year-old female Japanese domestic cat who had undergone mammectomy after a diagnosis of breast adenocarcinoma. The owner strongly requested immunotherapy for QOL maintenance. We administered LAK cells four times over a period of 5 months. Autologous peripheral blood mononuclear cells (PBMCs) fractionated using density gradient centrifugation were cultured in the media containing a high concentration of interleukin-2 and supplemented with 2.5% fetal calf serum. The derived LAK cells were centrifuged, suspended in 10 ml of saline containing 1% of the subject’s own blood, and infused into the cephalic vein of the cats over 30 min. The composition ratios of CD3, CD4, CD8, and CD21 were evaluated by flow cytometry. Bacterial culture and endotoxin testing for a sample of LAK cells showed negative results in both the cases. The leukocyte and erythrocyte counts and the body temperature were assessed on days 7, 14, and 21 after the transfusion. No abnormal signs were observed in either case, which confirmed the safety of the procedure. QOL scores showed no significant changes after the treatment, and the body temperature remained steady throughout the treatment. The findings from these cases suggest that the transplantation of LAK cells derived from PBMCs may be safe and feasible for use in cats, regardless of their age.Keywords: CD4-CD8 ratio, Immunotherapy, Lymphokine-activated killer cells, T lymphocytes, Transplantatio

Commissioning and quality assurance of Dynamic WaveArc irradiation

A novel three-dimensional unicursal irradiation technique "Dynamic WaveArc" (DWA), which employs simultaneous and continuous gantry and O-ring rotation during dose delivery, has been implemented in Vero4DRT. The purposes of this study were to develop a commissioning and quality assurance procedure for DWA irradiation, and to assess the accuracy of the mechanical motion and dosimetric control of Vero4DRT. To determine the mechanical accuracy and the dose accuracy with DWA irradiation, 21 verification test patterns with various gantry and ring rotational directions and speeds were generated. These patterns were irradiated while recording the irradiation log data. The differences in gantry position, ring position, and accumulated MU (EG, ER, and EMU, respectively) between the planned and actual values in the log at each time point were evaluated. Furthermore, the doses delivered were measured using an ionization chamber and spherical phantom. The constancy of radiation output during DWA irradiation was examined by comparison with static beam irradiation. The mean absolute error (MAE) of EG and ER were within 0.1° and the maximum error was within 0.2°. The MAE of EMU was within 0.7 MU, and maximum error was 2.7 MU. Errors of accumulated MU were observed only around control points, changing gantry, and ring velocity. The gantry rotational range, in which EMU was greater than or equal to 2.0 MU, was not greater than 3.2%. It was confirmed that the extent of the large differences in accumulated MU was negligibly small during the entire irradiation range. The variation of relative output value for DWA irradiation was within 0.2%, and this was equivalent to conventional arc irradiation with a rotating gantry. In conclusion, a verification procedure for DWA irradiation was designed and implemented. The results demonstrated that Vero4DRT has adequate mechanical accuracy and beam output constancy during gantry and ring rotation

Feasibility evaluation of a new irradiation technique: three-dimensional unicursal irradiation with the Vero4DRT (MHI-TM2000).

The Vero4DRT (MHI-TM2000) is a newly designed unique image-guided radiotherapy system consisting of an O-ring gantry. This system can realize a new irradiation technique in which both the gantry head and O-ring continuously and simultaneously rotate around the inner circumference of the O-ring and the vertical axis of the O-ring, respectively, during irradiation. This technique creates three-dimensional (3D) rotational dynamic conformal arc irradiation, which we term '3D unicursal irradiation'. The aim of this study was to present the concept and to estimate feasibility and potential advantages of the new irradiation technique. Collision maps were developed for the technique and a 3D unicursal plan was experimentally created in reference to the collision map for a pancreatic cancer case. Thereafter, dosimetric comparisons among the 3D unicursal, a two-dimensionally rotational dynamic conformal arc irradiation (2D-DCART), and an intensity-modulated radiation therapy (IMRT) plan were conducted. Dose volume data of the 3D unicursal plan were comparable or improved compared to those of the 2D-DCART and IMRT plans with respect to both the target and the organs at risk. The expected monitor unit (MU) number for the 3D unicursal plan was only 7% higher and 22.1% lower than the MUs for the 2D-DCART plan and IMRT plan, respectively. It is expected that the 3D unicursal irradiation technique has potential advantages in both treatment time and dose distribution, which should be validated under various conditions with a future version of the Vero4DRT fully implemented the function

Intrafractional tracking accuracy in infrared marker-based hybrid dynamic tumour-tracking irradiation with a gimballed linac.

[Purpose]To verify the intrafractional tracking accuracy in infrared (IR) marker-based hybrid dynamic tumour tracking irradiation ("IR Tracking") with the Vero4DRT. [Materials and methods]The gimballed X-ray head tracks a moving target by predicting its future position from displacements of IR markers in real-time. Ten lung cancer patients who underwent IR Tracking were enrolled. The 95th percentiles of intrafractional mechanical (iE^[95]_M), prediction (iE^[95]_P), and overall targeting errors (iE^[95]_T ) were calculated from orthogonal fluoroscopy images acquired during tracking irradiation and from the synchronously acquired log files. [Results]Averaged intrafractional errors were (left–right, cranio-caudal [CC], anterior–posterior [AP]) = (0.1 mm, 0.4 mm, 0.1 mm) for iE^[95]_M, (1.2 mm, 2.7 mm, 2.1 mm) for iE^[95]_P , and (1.3 mm, 2.4 mm, 1.4 mm) for iE^[95]_T. By correcting systematic prediction errors in the previous field, the iE^[95]_P was reduced significantly, by an average of 0.4 mm in the CC (p < 0.05) and by 0.3 mm in the AP (p < 0.01) directions. [Conclusions]Prediction errors were the primary cause of overall targeting errors, whereas mechanical errors were negligible. Furthermore, improvement of the prediction accuracy could be achieved by correcting systematic prediction errors in the previous field

Intra- and interfractional variations in geometric arrangement between lung tumours and implanted markers.

[Purpose]To quantify the intra- and interfractional variations between lung tumours and implanted markers.[Materials and methods]Gold markers were implanted transbronchially around a lung tumour in fifteen patients. They underwent four-dimensional computed tomography scans twice, and the centroids of the tumour and markers were determined. Intrafractional variations were defined as the residual tumour motions relative to the markers due to respiration from the end-exhale phase. Interfractional variations were defined as the residual setup errors after correction for the position of the implanted markers in end-exhale phase images.[Results]The intrafractional variations differed between patients. The root mean squares of standard deviations for each phase were 0.6, 0.9, and 1.5 mm in the right–left, anterior–posterior, and superior–inferior directions, respectively. The maximum difference in intrafractional variation among 10 phases was correlated with the amplitude of tumour motion in all directions and the tumour-marker distance in the anterior–posterior and superior–inferior directions. The interfractional variations were within 2.5 mm.[Conclusions]The intrafractional variations differed according to the amount of tumour motion and the tumour-marker distance. Additionally, interfractional variations of up to 2.5 mm were observed. Thus, a corresponding margin should be considered during implanted marker-based beam delivery to account for these variations