Long-Term and Short-Interval Assessment of Self-Reported Urinary and Sexual Functions after Nerve-Sparing Radical Hysterectomy: A Prospective Cohort Study.

The aim of this study was to determine the impact of nerve preservation confirmed by intraoperative electrical stimulation (IES) on subjective symptoms of urinary and sexual function in uterine cervical cancer patients who underwent radical hysterectomies. This study included 85 patients who underwent type C radical hysterectomy with IES. Pelvic splanchnic nerve preservation with IES after hysterectomy (nerve-stimulation positive group) was confirmed in 61 women and 24 women did not have nerve preservation (negative group). Urinary function was assessed with the Overactive Bladder Symptom Score (OABSS), International Prostate Symptom Score (IPSS), and International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF) questionnaires. Sexual function was surveyed using the Female Sexual Function Index (FSFI). Longitudinal changes in those scores according to response to nerve-stimulation were evaluated using a generalized estimating equation. IPSS quality of life (QOL) scores were significantly better in the nerve-stimulation positive group compared with the scores in the negative group until 12 months after surgery, whereas OABSS, IPSS total, IPSS voiding, and ICIQ-SF scores evaluating urinary symptoms were not significantly different between the two groups. FSFI scores were better in the nerve-stimulation positive group 36 months after surgery compared with the scores in the negative group. In this study, we assessed self-reported urinary and sexual symptoms after nerve-sparing radical hysterectomy (NSRH) with IES in the long term. We demonstrated that nerve-sparing significantly reduced distress associated with QOL until 1 year, improved urinary storage symptoms at 2 years, and sexual symptoms 3 years after surgery.

Cytokine and chemokine profiles in ulcerative colitis relapse after coronavirus disease 2019 vaccination.

Coronavirus disease 2019 (COVID-19) vaccines are highly effective; however, vaccine-related adverse events, including autoimmunity, have been reported. Case reports describing relapse or new-onset of ulcerative colitis (UC) after COVID-19 mRNA vaccination are available. However, the molecular mechanisms underlying the development of colonic inflammation associated with COVID-19 mRNA vaccination are poorly understood. Furthermore, it is unclear whether the relapse of UC after COVID-19 vaccination is driven by unique cytokine responses that differ from those of UC not associated with vaccination. mRNAs derived from COVID-19 vaccines are potent inducers of type I IFN response. We encountered three cases of UC relapse after COVID-19 vaccination. mRNA expressions of IFN-α, IFN-ß, IL-1ß, and IL-12/23p40 showed higher tendency in the colonic mucosa of patients with UC associated with vaccination compared with those not associated with vaccination. In contrast, the expressions of C-X-C motif chemokine ligand 9 (CXCL9) and CXCL10 were comparable. Immunofluorescence analyses also showed higher expression of IFN-α in the colonic mucosa of patients with UC associated with COVID-19 vaccination than in those not associated with vaccination. Taken together, these data suggest that the colonic mucosa of patients with UC who relapsed after COVID-19 vaccination was characterized by enhanced type I IFN responses.

Evaluation of the one-step nucleic acid amplification assay for detecting lymph node metastasis in patients with cervical and endometrial cancer: A multicenter prospective study.

OBJECTIVE: This multicenter study aimed to evaluate the accuracy of the one-step nucleic acid amplification (OSNA) assay in diagnosing lymph node metastasis (LNM) in patients with cervical and endometrial cancers. METHODS: Surgically removed LNs from patients with cervical and endometrial cancer were sectioned at 2-mm intervals along the short axis direction and alternately examined using the OSNA assay and conventional histopathological examination. Ultrastaging (200-µm LN sections) was performed for metastatic LNs using hematoxylin and eosin staining and immunostaining with an anti-CK19 antibody in cases where the OSNA assay and histopathological examination (performed using 2-mm LN sections) results showed discordance. RESULTS: A total of 437 LNs from 133 patients were included; 61 patients (14%) showed metastasis by histopathological examination, with a concordance rate of 0.979 (95% confidence interval [CI]: 0.961-0.991) with the OSNA assay. The sensitivity and specificity of the OSNA assay were 0.918 (95% CI: 0.819-0.973) and 0.989 (95% CI: 0.973-0.997), respectively. Discordance between the two methods was observed in nine LNs (2.1%), and allocation bias of metastatic foci was identified as the major cause of discordance. CONCLUSIONS: The OSNA assay showed equally accurate detection of LN metastasis as the histopathological examination. We suggest that the OSNA assay may be a useful tool for the rapid intraoperative diagnosis of LN metastasis in patients with cervical and endometrial cancers.

Assessing the Significance of Lymphadenectomy in Older Patients with Stage I Endometrial Cancer: A Single-Center, Retrospective Cohort Study.

Advantages of lymphadenectomy for early stage endometrial cancer remain controversial. Lymphadenectomy had been routinely omitted for patients aged ≥ 70 years at our institute if lymph node metastasis was unsuspected due to an increased risk of peri- and postsurgical complications. Since 2013, with the introduction of minimally invasive surgery and considering the heterogeneous medical conditions, we started performing lymphadenectomy in patients who were considered well-tolerated. We retrospectively investigated our clinical database to assess the effect of lymphadenectomy in older patients with early stage endometrial carcinoma. Patients aged ≥ 70 years, preoperatively diagnosed with stage I endometrial carcinoma, and who underwent lymphadenectomy between 2013 and 2021 at Tohoku University Hospital were included in the lymphadenectomy group (n = 33), whereas patients who underwent surgery without lymphadenectomy before the end of 2012 were included in the no-lymphadenectomy group (n = 49). Clinical parameters and patient outcomes, such as disease-free survival (DFS) and disease-specific survival (DSS), were compared. The median age was significantly higher and fewer patients received adjuvant chemotherapy in the no-lymphadenectomy group. Neither DSS nor DFS differed significantly between the two groups. Five-year-DFS rates were 77.2% and 82.5% and 5-year-DSS rates were 89.7% and 97.8% for the lymphadenectomy and no-lymphadenectomy groups, respectively. No significant differences were observed in the subsequent survival analysis by substage, histological subtype, or risk of recurrence. Our results suggest that the indications for lymphadenectomy in older patients should be individually optimized according to the risk of recurrence and postoperative complications.

Clinical issues of surgery for uterine endometrial cancer in Japan.

OBJECTIVE: The mainstay of treatment for uterine endometrial cancer is surgery, and recurrent-risk cases require multidisciplinary treatment, including surgery, chemotherapy and radiation therapy. METHODS: The standard surgery for uterine endometrial cancer is hysterectomy and bilateral salpingooophorectomy, with additional retroperitoneal lymph node dissection and omentectomy, depending on the case. The appropriate treatment is determined based on the risk classification, such as the depth of invasion into the myometrium, diagnosis of histological type and grade, and risk assessment of lymph node metastasis. RESULTS: Recently, minimally invasive surgery has been widely used not only in low-risk patients but also in intermediate- and high-risk patients. In low-risk patients, the possibility of ovarian preservation is discussed from a healthcare perspective for young women. Determining the need for retroperitoneal lymph node dissection based on sentinel lymph node evaluation may contribute in minimizing the incidence of post-operative lymphedema while ensuring accurate diagnosis of lymph node metastasis. Recently, many studies using sentinel lymph nodes have been reported for patients with uterine endometrial cancer, and the feasibility of sentinel lymph node mapping surgery has been proven. Unfortunately, sentinel lymph node biopsy and sentinel lymph node mapping surgery have not been widely adopted in surgery for uterine cancer in Japan. In addition, the search for biomarkers, such as RNA sequencing using The Cancer Genome Atlas, metabolic profile and lipidomic profile for early detection and prognostic evaluation, has been actively pursued. CONCLUSIONS: Gynecologic oncologists expect to be able to provide uterine endometrial cancer patients with appropriate treatment that preserves their quality of life without compromising oncologic outcomes in the near future.

Risk assessment in the patients with uterine cervical cancer harboring intermediate risk factors after radical hysterectomy: a multicenter, retrospective analysis by the Japanese Gynecologic Oncology Group.

BACKGROUND: Adjuvant therapy is usually considered for surgically treated patients with uterine cervical cancer harboring intermediate risk (IR) factors such as large tumor diameter, stromal invasion to the outer half, and lymphovascular space invasion (LVSI). However, the indications and types of adjuvant therapy for the IR group remain controversial. This study aimed to analyze the differences in patient outcomes in the IR group to provide novel insights for tailoring adjuvant therapy. METHODS: Data from 6192 patients with cervical cancer who underwent radical hysterectomy at 116 institutions belonging to the Japanese Gynecologic Oncology Group were reviewed. RESULTS: In total, 1688 patients were classified into the IR group, of whom 37.3% did not receive adjuvant therapy. Conversely, approximately equal proportions of the remaining patients received adjuvant radiotherapy, concurrent chemoradiotherapy, and chemotherapy. Patients with all three risk factors showed worse overall survival than those with one or two risk factors. In addition to LVSI, non-squamous cell carcinoma histology, and vaginal invasion were identified as independent risk factors for both recurrence and mortality in multivariate analyses. Tumor diameter greater than 40 mm and surgical center volume were identified as independent risk factors for recurrence. Stromal invasion to the outer half and ovarian metastasis were identified as independent risk factors for mortality. CONCLUSIONS: This study revealed the significant differences in prognosis in the IR group. The indications for adjuvant therapy should be further studied, focusing on conventional risk factors and other pathological findings.

A Retrospective Analysis of Clinical Biomarkers for Olaparib Maintenance Therapy in Patients with Recurrent Ovarian Cancer.

Poly(ADP-ribose) polymerase (PARP) inhibitors theoretically promote synthetic lethality in cancer cells with homologous recombination deficiency (HRD). However, clinical evidence indicates that PARP inhibitors are also effective for treating HRD-negative ovarian cancer. The PARP inhibitor olaparib became available in Japan as a maintenance therapy for platinum-sensitive recurrent ovarian cancer regardless of homologous recombination status in April 2018. The purpose of this study was to identify potential clinical biomarkers for olaparib sensitivity in patients with recurrent ovarian cancer. Clinical information about the patients with recurrent ovarian cancer treated with olaparib maintenance therapy (OMT) was retrospectively collected. OMT duration was used as an indicator for olaparib sensitivity. The relationship between OMT duration and clinical parameters was statistically analyzed. We found a positive correlation between OMT duration and progression-free survival (PFS) or treatment free interval (TFI). In some cases, OMT duration exceeded PFS before olaparib introduction. We also found that more than half of the patients with measurable target lesions at the time of OMT introduction showed partial or complete response to OMT. These results validated the effectiveness of OMT and identified PFS and TFI as potential clinical markers for olaparib sensitivity in the patients with recurrent ovarian cancer.

MicroRNA-152 Regulates Endometrial Serous Carcinoma Cell Motility by Suppressing Matrix Metalloproteinase 10 Expression.

MicroRNA-152 (miR-152) expression has been reported to be associated with poor prognosis in patients with endometrial serous carcinoma (ESC). However, the function of miR-152 in ESCs is not fully understood. The present study aimed to investigate the involvement of miR-152 in ESC progression. The influence of miR-152 overexpression on cell proliferation and motility was assessed by transfecting two human ESC cell lines, USPC-1 and SPAC-1-L, with a miR-152 precursor. MiR-152 overexpression increased apoptosis and inhibited the proliferation of the two ESC cell lines. Cell motility was also suppressed in both cell lines following precursor transfection. Conversely, miR-152 inhibitor transfection led to an increase in cell migration ability, suggesting the involvement of miR-152 in ESC cell motility. Results of the analysis of publicly available messenger RNA dataset indicated that high expression of matrix metalloproteinase 10 (MMP10), one of the predicted targets of miR-152 by microRNA target prediction database, was a poor prognostic factor for ESC. In vitro examination results revealed that miR-152 overexpression reduced MMP10 expression, and knockdown of MMP10 significantly reduced cell motility. This study elucidates the function of miR-152 as a tumor suppressor in ESCs. We demonstrated that miR-152 plays an important role in ESC cell motility by regulating MMP10 expression.

Rethinking the significance of surgery for uterine cervical cancer.

BACKGROUND: Treatment strategies based on histological subtypes are unestablished. AIMS: Rethinking the significance of surgery for uterine cervical cancer. METHODS: Using the database of cervical cancer stages IB-IIB with extensive hysterectomy (Federation of Gynecology and Obstetrics [FIGO] 2008) established by the Japanese Gynecologic Oncology Group network, we conducted a clinicopathological study of cervical cancer cases reclassified according to the FIGO 2018 staging. In stage IB (FIGO 2018) cervical cancer patients, there was no significant difference in treatment outcome according to histological type, but in stages IIA, IIB, and IIIC1 (FIGO 2018), the treatment outcome of nonsquamous cell carcinoma was significantly worse than that of squamous cell carcinoma. Considering post-treatment health care, it is important to consider ovarian preservation in young patients with cervical cancer, up to stage IIA (FIGO 2018) for squamous cell carcinoma and stage IB1 (FIGO 2018) for nonsquamous cell carcinoma, after careful evaluation of clinicopathological factors before surgery. DISCUSSION: Locally advanced adenocarcinoma of the cervix is a rare and refractory cancer that has been shown to have low radiosensitivity, and its treatment outcome is still unsatisfactory. A new therapeutic strategy involving multidisciplinary treatment in combination with perioperative chemotherapy at a facility that can provide highly curative surgical treatment is desired. CONCLUSION: Minimally invasive surgery is being introduced for the treatment of early-stage cervical cancer. However, the number of eligible cases should be expanded in a phased manner, based on an objective evaluation of surgical outcomes at the facilities. Omics analysis may be useful to develop a new treatment for human papillomavirus nonrelated cervical cancer, represented by gastric mucinous carcinoma.

[Successful R0 Resection of Two Metachronous Krukenberg Tumors from Gastric Cancer-A Case Report].

A 50s woman with a stomachache was referred to our hospital with diagnosed gastric cancer. Upper endoscopy showed a type 3 tumor in the lower gastric body, and CT demonstrated a pelvic tumor 10 cm in size. Laparoscopic surgery was performed; since the pelvic tumor was found to derive from the left ovary, left oophorectomy and total gastrectomy were performed. Pathological examination revealed that the ovarian tumor was a gastric cancer metastasis. Adjuvant chemotherapy with S-1 monotherapy was introduced. Four months after the operation, metastasis was suspected due to right ovary tumor edema. Due to the possibility of obtaining R0 resection and adverse events of chemotherapy, we chose right oophorectomy. Pathological examination demonstrated signet-ring cell cancer. Fourteen months after the first operation, the patient is alive with no recurrence or metastasis.

Prospective evaluation of sentinel node navigation surgery in Japanese patients with low-risk endometrial cancer-safety and occurrence of lymphedema.

OBJECTIVE: The present study aimed to clarify the occurrence rate of lymphedema and prognosis in patients with endometrial cancer according to sentinel lymph node biopsy alone with intraoperative histopathological examination. METHODS: The study included 45 consecutive patients with endometrial cancer treated at Tohoku University Hospital between October 2014 and August 2017. All patients had endometrial carcinoma with endometrioid histology Grade 1 or Grade 2 confirmed by biopsy and stage I on magnetic resonance imaging and/or computed tomography at their preoperative evaluation. Sentinel lymph node detection was performed by radioisotope and dye. Patients who were diagnosed intraoperatively as negative for sentinel lymph node metastasis did not undergo further systematic pelvic lymphadenectomy. The occurrence rate of lymphedema and prognosis was evaluated. RESULTS: Bilateral sentinel lymph nodes were detected in 44 of 45 patients (97%). Forty-three patients underwent sentinel lymph node biopsy alone, and only two patients underwent systematic lymphadenectomy. Sentinel lymph node metastases were detected in one patient intraoperatively and two patients postoperatively as ITCs. No patients experienced recurrence. New symptomatic lower-extremity lymphedema was identified in one of 43 patients (2.3%) who underwent sentinel lymph node biopsy alone. CONCLUSION: Sentinel lymph node biopsy alone with intraoperative histopathological diagnosis appears to be a safe and effective strategy to detect lymph node metastasis and to reduce the number of patients with lower-extremity lymphedema among patients with endometrial cancer.

Survey of the clinical practice pattern of using sentinel lymph node biopsy in patients with gynecological cancers in Japan: the Japan Society of Gynecologic Oncology study.

BACKGROUND: Sentinel lymph node (SN) biopsy is essential for evaluating survival and minimal treatment-related morbidity associated with cervical, endometrial, and vulvar cancer in Japan. As such, our aim in this study was to evaluate the current practice pattern of using SN biopsy for cervical, endometrial, and vulvar cancer in Japan. METHODS: We deployed a 47-question survey on the use of SN biopsy for gynecological cancers to 216 gynecological oncology training facilities. The survey included information on the use of SN biopsy for uterine (cervical and endometrial) and vulvar cancers; details on the type, timing, and concentration of tracers used; surgical approach used for SN biopsy; method of biopsy and pathological examination; and facilities' experience with clinical research on SN biopsy. RESULTS: The response rate was 84% (181/216), with 40 facilities (22%) having experience in SN biopsy for gynecological cancers, 34 (85%) for uterine cancers, and 15 (37%) for vulvar cancers. Radioisotope, indocyanine green (ICG), and blue dyes were available for the detection of uterine cancers in 21 (52%), 25 (62%), and 19 (48%) facilities and for vulvar cancers in 9 (22%), 3 (7%), and 11 (27%) facilities, respectively. Thirty-four facilities (85%) used intraoperative frozen section procedure for diagnosis when possible, with 24 (71%) of these facilities using 2-mm specimen cuts. Diagnosis included pathological examination (85%), immunostaining (57%), and one-step nucleic acid amplification (5%). CONCLUSION: Increasing research evidence, providing insurance coverage for radioisotope tracers, and increasing the availability of training are expected to increase the use of SN biopsy in Japan.

A Single Arm Prospective Pilot Study Examining the Efficacy and Safety of Bevacizumab Single Maintenance Therapy Following Platinum-Based Chemotherapy in Patients with Advanced or Recurrent Cervical Cancer.

Although the addition of bevacizumab to platinum-based combination chemotherapy has been recommended as a standard regimen for patients with advanced or recurrent cervical cancer, there is no clear evidence regarding the effectiveness of bevacizumab monotherapy as salvage chemotherapy. This study prospectively examined the efficacy and safety of switching from platinum-based chemotherapy combined with bevacizumab to single maintenance therapy in patients with advanced or recurrent cervical cancer. Patients were first treated with standard combination chemotherapy. However, if chemotherapy was discontinued because of an adverse event, bevacizumab monotherapy was continued for patients who agreed to participate in this study and provided written informed consent. The study protocol was approved by the Independent Review Board of Tohoku University School of Medicine (reception number 2017-1-540). A total of 15 patients (median age of 55 years, range 33-69 years) participated in this study. The median number of cycles of bevacizumab single maintenance administration was 8, and the main reasons for discontinuation were disease progression and adverse events. Bevacizumab single maintenance therapy had a disease control rate of 53.3% (CR 40%, PR 6.7%, SD 6.7%). The most frequent grade 3/4 clinical adverse events were proteinuria (5/15) and hypertension (4/15). No treatment-related deaths occurred. Bevacizumab single maintenance therapy was effective as salvage chemotherapy in patients with advanced or recurrent cervical cancer, and the safety profile was generally consistent with those reported in previous studies of bevacizumab monotherapy.

The Impact of Histological Subtype on Survival Outcome of Patients with Stage IIB-IVA Cervical Cancer Who Received Definitive Radiotherapy.

The impact of histologic subtype on definitive radiotherapy for patients with locally advanced cervical cancer remains unclear. The aim of this retrospective analysis was to assess clinicopathological findings and clinical outcome by histological type in patients with stage IIB-IVA cervical cancer. Ninety-two patients with stage IIB-IVA [International Federation of Gynecology and Obstetrics (FIGO) 2008] cervical cancer, who underwent definitive radiotherapy between 2013 to 2018, were identified as eligible for this study. The clinical information of the eligible patients was obtained from medical records of our hospital. Seventy-eight patients underwent concurrent chemoradiotherapy, and the remaining 14 patients received radiotherapy alone. Of 92 patients, 83 had squamous cell carcinoma (SCC) and 9 had non-SCC histology. Progression-free survival (PFS) rate of patients with non-SCC was significantly worse than of those with SCC (2-year PFS: 62.0% vs. 12.5%, p = 0.0020), but overall survival (OS) rate did not statistically differ between the two subtypes (2-year OS: 82.4% vs. 62.5%, p = 0.2157). Pelvic failure-free (PFF) rate of patients with non-SCC histology was significantly worse than of those with non-SCC (2-year PFF; 88.2% vs. 25.0%, p < 0.0001). In univariate analysis, non-SCC histology was associated with PFS rate, although there was no association with OS rate. In multivariate analysis, non-SCC histology and lymph node metastasis were independent prognostic factors for shorter PFS. In patients with stage IIB-IVA cervical cancer who underwent definitive radiotherapy, patients with non-SCC showed significantly worse PFS rate than those with SCC.

Weakly coupled 10-mode-division multiplexed transmission over 48-km few-mode fibers with real-time coherent MIMO receivers.

For weakly coupled mode-division multiplexed (MDM) transmission systems, we design and implement optical coherent receiver prototypes with real-time multiple-input multiple-output (MIMO) digital signal processing to equalize two degenerate linearly polarized modes with dual polarization. Using field programmable gate array circuits, we implement real-value 8 × 2 MIMO adaptive equalization with externally separated phase compensators based on the least mean square algorithm, which enables not only training equalization but also fast carrier-phase tracking. With the optical coherent MIMO receiver prototype, we demonstrate real-time weakly coupled 10 × MDM wavelength-division multiplexed dual-polarization quadrature phase shift keying transmission over 48-km few-mode fibers. This report shows a record number of multiplexed spatial modes, namely, 10 modes with dual polarization, in real-time MDM transmission experiments.

RICK/RIP2 is a NOD2-independent nodal point of gut inflammation.

Previous studies have shown that inhibition of receptor-interacting serine/threonine kinase (RICK) (also known as RIP2) results in amelioration of experimental colitis. This role has largely been attributed to nucleotide-binding oligomerization domain 2 (NOD2) signaling since the latter is considered a major inducer of RICK activation. In this study, we explored the molecular mechanisms accounting for RICK-mediated inhibition of inflammatory bowel disease (IBD). In an initial series of studies focused on trinitrobenzene sulfonic acid (TNBS)-colitis and dextran sodium sulfate (DSS)-colitis we showed that down-regulation of intestinal RICK expression in NOD2-intact mice by intra-rectal administration of a plasmid expressing RICK-specific siRNA was accompanied by down-regulation of pro-inflammatory cytokine responses in the colon and protection of the mice from experimental colitis. Somewhat surprisingly, intra-rectal administration of RICK-siRNA also inhibited TNBS-colitis and DSS-colitis in NOD2-deficient and in NOD1/NOD2-double deficient mice. In complementary studies of humans with IBD we found that expression of RICK, cellular inhibitor of apoptosis protein 2 (cIAP2) and downstream signaling partners were markedly increased in inflamed tissue of IBD compared to controls without marked elevations of NOD1 or NOD2 expression. In addition, the increase in RICK expression correlated with disease activity and pro-inflammatory cytokine responses. These studies thus suggest that NOD1- or NOD2-independenent activation of RICK plays a major role in both murine experimental colitis and human IBD.

Deficiency of Gankyrin in the small intestine is associated with augmented colitis accompanied by altered bacterial composition of intestinal microbiota.

BACKGROUND: Gankyrin (GK) is an oncoprotein which regulates inflammatory responses and its inhibition is considered as a possible anti-inflammatory therapy for inflammatory bowel disease (IBD). METHODS: In this study, we investigated the role of GK in epithelial cells using mice with intestinal epithelial cell-specific GK deletion in (i) the entire small intestine and colon (Villin-Cre;Gankyrinf/f) and (ii) the distal intestine and colon (Cdx2-Cre;Gankyrinf/f). RESULT: Unexpectedly, GK-deficiency in the upper small bowel augmented inflammatory activity compared with control mice when colitis was induced with dextran sodium sulfate. Biochemical analyses have revealed GK-deficiency to have caused reduction in the expression of antimicrobial peptides, α-Defensin-5 and -6, in the upper small bowel. Examination of human samples have further confirmed that the reduction of GK expression in the small bowel is associated with colonic involvement in human Crohn's disease. Through the sequencing of bacterial 16S rRNA gene amplicons, bacteria potentially deleterious to intestinal homeostasis such as Helicobacter japonicum and Bilophila were found to be over-represented in colitis induced Villin-Cre;Gankyrinf/f mice when compared to Gankyrinf/f control mice under the same condition. CONCLUSION: These results highlight the distinct site dependence of the pro- and anti-inflammatory functions of GK and provide important insights into the pathogenesis of IBD.

Dual-Site Cascade Oxygen Reduction Mechanism on SnO x/Pt-Cu-Ni for Promoting Reaction Kinetics.

Designing highly active oxygen reduction reaction (ORR) catalysts is crucial to boost the fuel cell economy. Previous research has mainly focused on Pt-based alloy catalysts in which surface Pt is the solely active site and the activity improvement was challenged by the discovered scaling relationship. Herein we report a new concept of utilizing dual active sites for the ORR and demonstrate its effectiveness by synthesizing a SnO x/Pt-Cu-Ni heterojunctioned catalyst. A maximum of 40% enhancement in the apparent specific activity, which corresponds to 10-fold enhancement on interface sites, is measured compared with pure Pt-Cu-Ni. Detailed investigations suggest an altered dual-site cascade mechanism wherein the first two steps occur on SnO x sites and the remaining steps occur on adjacent Pt sites, allowing a significant decrease in the energy barrier. This study with the suggested dual-site cascade mechanism shows the potential to overcome the ORR energy barrier bottleneck to develop highly active catalysts.

Chronic Fibro-Inflammatory Responses in Autoimmune Pancreatitis Depend on IFN-α and IL-33 Produced by Plasmacytoid Dendritic Cells.

In previous studies, we found that human IgG4-related autoimmune pancreatitis (AIP) and murine AIP are driven by activation of plasmacytoid dendritic cells (pDCs) producing IFN-α. In the present studies we examined additional roles of pDC-related mechanisms in AIP pathogenesis, particularly those responsible for induction of fibrosis. We found that in murine AIP (MRL/Mp mice treated with polyinosinic-polycytidylic acid) not only the pancreatic infiltration of immune cells but also the development of fibrosis were markedly reduced by the depletion of pDCs or blockade of type I IFN signaling; moreover, such treatment was accompanied by a marked reduction of pancreatic expression of IL-33. Conversely, polyinosinic-polycytidylic acid-induced inflamed pancreatic tissue in murine AIP exhibited increased expression of type I IFNs and IL-33 (and downstream IL-33 cytokines such as IL-13 and TGF-ß1). pDCs stimulated by type I IFN were the source of the IL-33 because purified populations of these cells isolated from the inflamed pancreas produced a large amount of IL-33 upon activation by TLR9 ligands, and such production was abrogated by the neutralization of type I IFN. The role of IL-33 in murine AIP pathogenesis was surprisingly important because blockade of IL-33 signaling by anti-ST2 Ab attenuated both pancreatic inflammation and accompanying fibrosis. Finally, whereas patients with both conventional pancreatitis and IgG4-related AIP exhibited increased numbers of acinar cells expressing IL-33, only the latter also exhibited pDCs producing this cytokine. These data thus suggest that pDCs producing IFN-α and IL-33 play a pivotal role in the chronic fibro-inflammatory responses underlying murine AIP and human IgG4-related AIP.