Demonstration of nuclear gamma-ray polarimetry based on a multi-layer CdTe Compton camera.

To detect and track structural changes in atomic nuclei, the systematic study of nuclear levels with firm spin-parity assignments is important. While linear polarization measurements have been applied to determine the electromagnetic character of gamma-ray transitions, the applicable range is strongly limited due to the low efficiency of the detection system. The multi-layer Cadmium-Telluride (CdTe) Compton camera can be a state-of-the-art gamma-ray polarimeter for nuclear spectroscopy with the high position sensitivity and the detection efficiency. We demonstrated the capability to operate this detector as a reliable gamma-ray polarimeter by using polarized 847-keV gamma rays produced by the [Formula: see text]([Formula: see text]) reaction. By combining the experimental data and simulated calculations, the modulation curve for the gamma ray was successfully obtained. A remarkably high polarization sensitivity was achieved, compatible with a reasonable detection efficiency. Based on the obtained results, a possible future gamma-ray polarimetery is discussed.

Late-gestation prediction of outcome in tricuspid valve dysplasia and Ebstein's anomaly using fetal tricuspid regurgitation waveform analysis.

OBJECTIVE: To investigate the criteria, based on fetal TR waveforms in late gestation, to predict biventricular circulation (BV) after birth in cases of tricuspid valve dysplasia (TVD) or Ebstein's anomaly diagnosed during the fetal period. METHODS: We included 35 consecutive cases diagnosed with TVD or Ebstein's anomaly during the fetal period between January 2008 and December 2021 at Kanagawa Children's Medical Center, Kanagawa, Japan. The maximum velocity and change in pressure over time of tricuspid regurgitation (TR) jet (dP/dt), estimated using TR waveforms obtained during the late-gestation period (gestational age ≥ 28 weeks), were collected from patient records. dP/dt was calculated by dividing the change in estimated right ventricular pressure obtained using Bernoulli's principle by the time taken for the TR maximum velocity to change from one-third to two-thirds of its peak value. The outcome was divided into four categories: BV, single ventricular circulation, neonatal death and fetal death. Patients with BV were included in the BV group, while patients with single ventricular circulation, neonatal death or fetal death were included in the non-BV (NBV) group. RESULTS: Overall, 19 and 16 patients were included in the BV and NBV groups, respectively. The median TR maximum velocity was 3.3 (range, 2.4-3.6) m/s in the BV group and 1.9 (range, 1.0-3.3) m/s in the NBV group. There were no cases of postnatal BV in fetuses with TR maximum velocity < 2.4 m/s; cases with TR maximum velocity of 2.4-3.3 m/s were observed in both BV and NBV groups. Receiver-operating-characteristics-curve analysis was performed on the 11 patients in the BV group and five patients in the NBV group with a TR maximum velocity of 2.4-3.3 m/s. dP/dt ≥ 350 mmHg/s and TR maximum velocity ≥ 2.9 m/s were identified as criteria for predicting the outcome in such cases. The performance of dP/dt ≥ 350 mmHg/s in predicting BV after birth in fetuses with TVD or Ebstein's anomaly was higher compared to that of TR maximum velocity ≥ 2.9 m/s (sensitivity, 90.9% vs 72.3% and specificity, 80.0% vs 80.0%, respectively). CONCLUSIONS: In fetuses with TVD or Ebstein's anomaly, the postnatal outcome may be BV or NBV when the TR maximum velocity is 2.4-3.3 m/s. In such cases, by combining the TR maximum velocity with dP/dt ≥ 350 mmHg/s, BV after birth may be predicted with greater accuracy. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Precise Measurement of Differential Cross Sections of the Σ

The differential cross sections of the Σ^{-}p→Λn reaction were measured accurately for the Σ^{-} momentum (p_{Σ}) ranging from 470 to 650 MeV/c at the J-PARC Hadron Experimental Facility. Precise angular information about the Σ^{-}p→Λn reaction was obtained for the first time by detecting approximately 100 reaction events at each angular step of Δcosθ=0.1. The obtained differential cross sections show a slightly forward-peaking structure in the measured momentum regions. The cross sections integrated for -0.7≤cosθ≤1.0 were obtained as 22.5±0.68 [statistical error(stat.)] ±0.65 [systematic error(syst.)] mb and 15.8±0.83(stat)±0.52(syst) mb for 470

Observation of Coulomb-Assisted Nuclear Bound State of Ξ

In an emulsion-counter hybrid experiment performed at J-PARC, a Ξ^{-} absorption event was observed which decayed into twin single-Λ hypernuclei. Kinematic calculations enabled a unique identification of the reaction process as Ξ^{-}+^{14}N→_{Λ}^{10}Be+_{Λ}^{5}He. For the binding energy of the Ξ^{-} hyperon in the Ξ^{-}-^{14}N system a value of 1.27±0.21 MeV was deduced. The energy level of Ξ^{-} is likely a nuclear 1p state which indicates a weak ΞN-ΛΛ coupling.

g Factor of the

The gyromagnetic factor of the low-lying E=251.96(9) keV isomeric state of the nucleus ^{99}Zr was measured using the time-dependent perturbed angular distribution technique. This level is assigned a spin and parity of J^{π}=7/2^{+}, with a half-life of T_{1/2}=336(5) ns. The isomer was produced and spin aligned via the abrasion-fission of a ^{238}U primary beam at RIKEN RIBF. A magnetic moment |µ|=2.31(14)µ_{N} was deduced showing that this isomer is not single particle in nature. A comparison of the experimental values with interacting boson-fermion model IBFM-1 results shows that this state is strongly mixed with a main νd_{5/2} composition. Furthermore, it was found that monopole single-particle evolution changes significantly with the appearance of collective modes, likely due to type-II shell evolution.

Efficiency of leukocyte depletion filters and micro-aggregate filters following intra-operative cell salvage during cesarean delivery.

BACKGROUND: Intra-operative cell salvage is not routinely used during cesarean delivery because it is not cost-effective for patients at low risk of hemorrhage and there are theoretical concerns about amniotic fluid embolism. Some guidelines recommend using leukocyte depletion filters to decrease the risk of amniotic fluid embolism before re-infusing salvaged blood, but these filters are not available in Japan. We compared the efficacy and safety of leukocyte depletion and micro-aggregate filters in combination with intra-operative cell salvage during cesarean delivery. METHODS: Blood was collected in a Cell Saver 5 reservoir during cesarean delivery. Four samples were collected: pre-wash, post-wash, post-filtration with a leukocyte depletion filter and post-filtration with a micro-aggregate filter. Each sample was analyzed for amniotic fluid markers of zinc coproporphyrin-1 and sialyl-Tn, for fetal hemoglobin, and the sample underwent pathological examination for white blood cells and squamous cells. Post-filtration samples were compared using paired t-tests with P <0.05 indicating statistical significance. RESULTS: Zinc coproporphyrin-1 and sialyl-Tn were negative at almost all sample points. Squamous cells decreased by 59.1% post-wash and 91.2% post-filtration using a leukocyte depletion filter. Leukocyte depletion filters removed 99.7% of white blood cells and were more effective in removing white blood cells than micro-aggregate filters (P=0.02). CONCLUSION: Leucocyte depletion filters are more effective in removing white blood cells and squamous cells than micro-aggregate filters, and their introduction for intra-operative cell salvage during cesarean delivery should be considered in Japanese clinical practice.

First Determination of the Level Structure of an sd-Shell Hypernucleus, _{Λ}

We report on the first observation of γ rays emitted from an sd-shell hypernucleus, _{Λ}^{19}F. The energy spacing between the ground state doublet, 1/2^{+} and 3/2^{+} states, of _{Λ}^{19}F is determined to be 315.5±0.4(stat)_{-0.5}^{+0.6}(syst) keV by measuring the γ-ray energy of the M1(3/2^{+}→1/2^{+}) transition. In addition, three γ-ray peaks are observed and assigned as E2(5/2^{+}→1/2^{+}), E1(1/2^{-}→1/2^{+}), and E1(1/2^{-}→3/2^{+}) transitions. The excitation energies of the 5/2^{+} and 1/2^{-} states are determined to be 895.2±0.3(stat)±0.5(syst) and 1265.6±1.2(stat)_{-0.5}^{+0.7}(syst) keV, respectively. It is found that the ground state doublet spacing is well described by theoretical models based on existing s- and p-shell hypernuclear data.

Associations of aniseikonia with metamorphopsia and retinal displacements after epiretinal membrane surgery.

PurposeTo determine the correlation of the degree of aniseikonia with the retinal displacements and metamorphopsia in patients that have undergone successful epiretinal membrane (ERM) surgery.MethodsSubjects were 28 eyes with an ERM in 28 patients. The New Aniseikonia Test (NAT) and M-CHARTS were used to quantify the degree of preoperative and postoperative aniseikonia and metamorphopsia. We also evaluated the distance between the intersections of 2 sets of retinal vessels situated vertically or horizontally by using spectral-domain optical coherence tomography (SD-OCT) images in 28 patients.ResultsThe vertical score of M-CHARTS (MV) was not significantly improved, but the horizontal score of M-CHARTS (MH) was significantly improved at 1 week, 1 month, and 3 months postoperatively. The preoperative NAT score was significantly correlated with the preoperative MH. The NAT score at 3 months was significantly correlated with the MH at 3 months and the MV at 3 months. The preoperative NAT score was significantly correlated with the ratio of the vertical retinal displacement at 1 month and at 3 months after surgery. However, the NAT scores did not improve significantly at any postoperative times.ConclusionsThe degree of aniseikonia was significantly correlated with the degree of metamorphopsia and the tangential displacement of the retina after ERM surgery. Aniseikonia is difficult to improve and metamorphopsia may be a more sensitive parameter to detect the functional recovery after successful ERM surgery.

Formation of new blood vessels during gastric ulcer healing. Role of bone marrow derived endothelial progenitor cells.

Regeneration of blood vessels (neovascularization) is critical for gastric ulcer (GU) healing. The contributions of bone marrow-derived endothelial progenitor cells (BMD-EPCs) to neovascularization during GU healing are not fully elucidated. Our specific aims were to determine whether in GU, BMD-EPCs are incorporated into blood vessels of GU granulation tissue jointly with ECs, thus forming hybrid vessels; or, form separate vessels consisting of only BMD-EPCs. GUs were induced in rats by serosal application of acetic acid. Vascular cast studies were performed at 7, 21 and 60 days after GU induction and tissue specimens were immunostained for CD34, CD133, VEGFR2, and SDF-1 at 14 days. Human relevance was determined using archival human GU specimens. In rat GU granulation tissue BMD-EPCs constituted 28 ± 3% of all cells lining newly formed blood vessels, and were nested between fully differentiated ECs. In rat GU granulation tissue, expression of stromal derived factor-1 (SDF-1) - the major chemoattractant for BMD-EPCs was strongly upregulated. In human GU specimens, BMD-EPCs were also present in granulation tissue constituting 34 ± 3% of all cells lining blood vessels and jointly formed hybrid vessels with differentiated ECs. Our study uncovered that BMD-EPCs incorporate into newly formed blood vessels in GU granulation tissue; and, together with ECs of pre-existing vessels, contribute to and support neovascularization through vasculogenesis. This study is the first demonstration that vasculogenesis occurs during GU healing in both humans and in rats.

BRCAness is beneficial for indicating triple negative breast cancer patients resistant to taxane.

AIM: Triple negative breast cancer (TNBC) is a heterogeneous disease and is associated with the cancer stem cell (CSC), basal-like, and BRCA1 function deficient (BRCAness) subtypes. We examined these 3 subtypes in TNBC and compared their chemosensitivity against anthracycline or taxane with a special attention to BRCAness. METHODS: Sixty-six TNBC cases were obtained from a randomized phase II trial comparing TCx6 (TC6) with FEC-Docetaxel (FEC-D) as neoadjuvant chemotherapy. The core needle specimens before chemotherapy were used for subtyping. The basal-like and CSC subtypes were identified by immunohistochemistry; CK5/6 and EGFR staining for the basal-like subtype and ALDH1 staining for the CSC subtype. The BRCAness subtype was examined by Multiplex Ligation-dependent Probe Amplification (MLPA). Correlations between subgroups and pCR rates according to each regimen and subtype were examined. RESULTS: The basal-like and BRCAness subtypes were significantly associated (p = 0.010) with the other subtypes, but not the CSC subtype. The pCR rates were higher with FEC-D than with TC6 in the basal-like (54.5% vs 14.3%, p = 0.081) and BRCAness (56.2% vs 16.7%, p = 0.030) subtypes. Both were not effective in the CSC subtype (18.2% vs 11.8%, p = 1.00). CONCLUSION: BRCAness identified by MLPA was practically useful for treatment selection for avoiding taxane. ALDH1 may be considered as a marker for the CSC subtype requiring novel agents.

Observation of Spin-Dependent Charge Symmetry Breaking in ΛN Interaction: Gamma-Ray Spectroscopy of _{Λ}

The energy spacing between the spin-doublet bound state of _{Λ}^{4}He(1^{+},0^{+}) was determined to be 1406±2±2 keV, by measuring γ rays for the 1^{+}→0^{+} transition with a high efficiency germanium detector array in coincidence with the ^{4}He(K^{-},π^{-})_{Λ}^{4}He reaction at J-PARC. In comparison to the corresponding energy spacing in the mirror hypernucleus _{Λ}^{4}H, the present result clearly indicates the existence of charge symmetry breaking (CSB) in ΛN interaction. By combining the energy spacings with the known ground-state binding energies, it is also found that the CSB effect is large in the 0^{+} ground state but is vanishingly small in the 1^{+} excited state, demonstrating that the ΛN CSB interaction has spin dependence.

Nutritional management of anastomotic leakage after colorectal cancer surgery using elemental diet jelly.

BACKGROUND/AIMS: Anastomotic leakage is major complication of colorectal surgery. Total parenteral nutrition (TPN) and fasting are conservative treatments for leakage in the absence of peritonitis in Japan. Elemental diet (ED) jelly is a completely digested formula and is easily absorbed without secretion of digestive juices. The purpose of this study was to assess the safety of ED jelly in management of anastomotic leakage. METHODOLOGY: Six hundred and two patients who underwent elective surgery for left side colorectal cancer from January 2008 to December 2011 were included in the study. Pelvic drainage was performed for all patients. Sixty-three (10.5%) patients were diagnosed with an anastomotic leakage, and of these, 31 (5.2%) without diverting stoma were enrolled in this study. RESULTS: Sixteen patients received TPN (TPN group) and 15 patients received ED jelly (ED group). The duration of intravenous infusion was significantly shorter in the ED group than in the TPN group (15 days versus 25 days, P= 0.008). In the TPN group, catheter infection was occurred in 2 patients who required re-insertion of the catheter. CONCLUSION: Conservative management of anastomotic leakage after colorectal surgery with ED jelly appears to be a safe and useful approach.

Randomised phase II trial of S-1 plus oxaliplatin vs S-1 in patients with gemcitabine-refractory pancreatic cancer.

BACKGROUND: This randomised, open-label, multicenter phase II study compared progression-free survival (PFS) of S-1 plus oxaliplatin (SOX) with that of S-1 alone in patients with gemcitabine-refractory pancreatic cancer. METHODS: Patients with confirmed progressive disease following the first-line treatment with a gemcitabine-based regimen were randomised to receive either S-1 (80/100/120 mg day(-1) based on body surface area (BSA), orally, days 1-28, every 6 weeks) or SOX (S-1 80/100/120 mg day(-1) based on BSA, orally, days 1-14, plus oxaliplatin 100 mg m(-2), intravenously, day 1, every 3 weeks). The primary end point was PFS. RESULTS: Between January 2009 and July 2010, 271 patients were randomly allocated to either S-1 (n=135) or SOX (n=136). Median PFS for S-1 and SOX were 2.8 and 3.0 months, respectively (hazard ratio (HR)=0.84; 95% confidence interval (CI), 0.65-1.08; stratified log-rank test P=0.18). Median overall survival (OS) was 6.9 vs 7.4 months (HR=1.03; 95% CI, 0.79-1.34; stratified log-rank test P=0.82). The response rate (RR) was 11.5% vs 20.9% (P=0.04). The major grade 3/4 toxicities (S-1 and SOX) were neutropenia (11.4% and 8.1%), thrombocytopenia (4.5% and 10.3%) and anorexia (12.9% and 14.7%). CONCLUSIONS: Although SOX showed an advantage in RR, it provided no significant improvement in PFS or OS compared with S-1 alone.

A prospective feasibility study of sentinel node biopsy by modified Indigocarmine blue dye methods after neoadjuvant chemotherapy for breast cancer.

BACKGROUND: Although sentinel lymph node biopsy (SLNB) is a standard staging method for assessing nodal status of breast cancer patients, SLNB after neoadjuvant chemotherapy (NAC) remains controversial. The aim of this study was to validate the practicality and accuracy of SLNB by our modified Indigocarmine blue dye methods following NAC. METHODS: One hundred consecutive cases with breast cancers treated by NAC were enrolled in this study. After NAC, all patients underwent SLNB performed by our modified Indigocarmine blue dye methods without radioisotope, followed by back-up axillary lymph node dissection (ALND). RESULTS: Sentinel nodes (SNs) were identified in 94 cases (identification rate, 94%); the accuracy was 94.7% (89/94 cases); and the false negative rate (FNR) 13.5% (5/37 cases). For cases with vs. without clinically evident metastatic nodes before NAC, the identification rate was 92.4% (61/66 cases) vs. 97.1% (33/34 cases); the accuracy 91.8% (56/61 cases) vs. 97.0% (32/33 cases) and the FNR 16.1% (5/31 cases) vs. 0% (0/6 case), respectively. There were six patients without identified SNs, three of them had metastatic nodes. False negatives occurred in five cases; in four, fewer than two sentinel nodes had been removed. CONCLUSION: Following NAC, the accuracy of SLNB by modified Indigocarmine blue dye methods is adequate compared with other tracers. In patients in whom no SNs have been identified, lymphatic metastasis is likely and therefore ALND is recommended. For patients with cN0 prior to NAC, SLNB by modified Indigocarmine blue dye methods is clinically feasible, though controversial for patients with positive nodes.

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS): short-term outcome, functional changes in the future liver remnant, and tumor growth activity.

BACKGROUND: We compared clinical outcomes of associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) against those of classical 2-stage hepatectomy in treating metastatic liver disease. METHODS: Short-term outcomes, serial changes in volume of the future liver remnant (FLR), functional FLR volume, and tumor growth activity during the treatment period, were compared between our first 11 consecutive patients treated with ALPPS and 54 patients treated with classical 2-stage hepatectomy. RESULTS: Mortality in the ALPPS group (9%) tended to be higher than in the classical 2-stage group (2%, P = 0.341). The FLR hypertrophy ratio (FLR volume after vs. before the procedure) 1 week after the first operation in the ALPPS group (1.54 ± 0.18) exceeded that in the classical 2-stage group (1.19 ± 0.29, P = 0.005), being similar to the ratio at 3 weeks after the first procedure in the classical 2-stage group (1.40 ± 0.43). However, functional volume of the FLR in the ALPPS group 1 week after the first procedure (52.1%) tended to be smaller than that in the classical group 3 weeks after the first procedure (59.2%). CONCLUSIONS: ALPPS should be used with extreme caution, giving special attention to postoperative complications and grade of functional liver regeneration.

Differences in the developmental origins of the periosteum may influence bone healing.

BACKGROUND AND OBJECTIVE: The jaw bone, unlike most other bones, is derived from neural crest stem cells, so we hypothesized that it may have different characteristics to bones from other parts of the body, especially in the nature of its periosteum. The periosteum exhibits osteogenic potential and has received considerable attention as a grafting material for the repair of bone and joint defects. MATERIAL AND METHODS: Gene expression profiles of jaw bone and periosteum were evaluated by DNA microarray and real-time polymerase chain reaction. Furthermore, we perforated an area 2 mm in diameter on mouse frontal and parietal bones. Bone regeneration of these calvarial defects was evaluated using microcomputed tomography and histological analysis. RESULTS: The DNA microarray data revealed close homology between the gene expression profiles within the ilium and femur. The gene expression of Wnt-1, SOX10, nestin, and musashi-1 were significantly higher in the jaw bone than in other locations. Microcomputed tomography and histological analysis revealed that the jaw bone had superior bone regenerative abilities than other bones. CONCLUSION: Jaw bone periosteum exhibits a unique gene expression profile that is associated with neural crest cells and has a positive influence on bone regeneration when used as a graft material to repair bone defects. A full investigation of the biological and mechanical properties of jaw bone as an alternative graft material for jaw reconstructive surgery is recommended.

Evaluation of Rotational Vertebral Artery Occlusion Using Ultrasound Facilitates the Detection of Arterial Dissection in the Atlas Loop.

PURPOSE: Head rotation can cause occlusion of the vertebral artery most commonly at the atlas loop, and repetitive compression from head turning induces vertebral artery dissection (VAD). Although ultrasound examinations are useful in diagnosis, dissected lesions unaccompanied by hemodynamic changes can be overlooked. Because the narrowed, dissected vessel in the atlas loop may cause rotational occlusion, we confirmed whether adding submaximal head rotation to a cervical ultrasound examination would facilitate the detection of VAD in the atlas loop. METHODS: We investigated 7 patients who developed infarction in the posterior circulation and were clinically suspected of VAD. Using a 7.5-MHz linear probe, we recorded the waveform of the vertebral artery at the C4-C6 level and diagnosed rotational vertebral artery occlusion (RVAO) when head rotation induced the disappearance of end-diastolic flow. RESULTS: All 3 patients with VAD in the atlas loop demonstrated RVAO of the dissected vertebral arteries in the acute stroke phase. RVAO was not observed in the dissected vertebral arteries excepting the atlas loop, nor in the nondissected vertebral arteries of any patients. CONCLUSION: For posterior circulation stroke patients, adding submaximal head rotation to the cervical ultrasound examination facilitated the detection of VAD in the atlas loop.

Optimizing the selection of patients with low rectal cancer for intersphincteric resection by evaluating vertical invasion to the levator and external sphincter.

AIM: The indications for intersphincteric (ISR) anterior resection are not clearly defined. The aim of this study was to evaluate vertical extension of T2 or T3 low rectal cancer treated by rectal amputation to optimize patient selection for ISR. METHOD: The abdominoperineal excision specimens of T2 or T3 low rectal cancer from 53 patients treated between 1992 and 2004 were retrospectively reviewed. Vertical invasion was quantified by measuring the shortest distance between the tumour and the striated muscle (T-SM), assuming that this represented the surgical margin that would have be achieved had an ISR been performed. RESULTS: Involvement of the dentate line (DL) and intramural distal spread were independent risk factors for T-SM ≤ 2 mm. The T-SM was less when the inferior border of the tumour was on the distal side of the DL (r = 0.572, P < 0.001). The probability of involvement of the DL, intramural distal spread or either one of these being associated with T-SM ≤ 2 mm was 43, 46 and 43%, respectively. All patients without both intramural distal spread and involvement of the DL had T-SM > 2. CONCLUSION: We recommend that ISR should only be performed for patients with T2 or T3 low rectal cancer in whom the lowest edge of the tumour is above the DL and there is no intramural distal spread. Such patients are relatively unlikely to have a T-SM ≤ 2 mm.

Outcomes of immediate perforator flap reconstruction after skin-sparing mastectomy following neoadjuvant chemotherapy.

BACKGROUND: The impact of neoadjuvant chemotherapy (NACT) on immediate free flap breast reconstruction remains controversial. Furthermore, the oncological outcomes of immediate free flap breast reconstruction after skin-sparing mastectomy (SSM) following NACT remain unclear. This study aimed to investigate the surgical complications and oncological outcomes of immediate perforator flap reconstruction after SSM following NACT. METHODS: A total of 201 consecutive patients with indications for immediate perforator flap reconstruction after SSM were included between 2004 and 2012. Surgical and oncological outcomes were compared between patients with and without NACT. RESULTS: There were 38 patients in the NACT group and 163 in the non-NACT control group. The median age of the NACT group was 39.5 years, which was significantly younger than the control group (43.0 years; P < 0.05). Patients in the NACT group also had more advanced and aggressive disease (P < 0.05). There was no significant difference in the frequency of surgical complications between the groups, no difference in the type of complications, and no significant difference in the frequencies of major and minor complications. No patients in the NACT group had delayed adjuvant therapy. Eight patients (4%) developed recurrences, with a median follow-up time of 3.0 years. Local recurrences occurred in three control patients but no patients in the NACT group. CONCLUSION: NACT does not affect short-term or interim outcomes after immediate perforator flap reconstruction and may thus represent a safe and practical treatment option for the multidisciplinary treatment of breast cancer.