Silencing of tumoral carbohydrate sulfotransferase 15 reactivates lymph node pancreatic cancer T cells in mice

Limited intratumoral T-cell infiltration in pancreatic ductal adenocarcinoma (PDAC) is an obstacle to immunotherapy, yet the efficient approach to enhance tumor-infiltrating T cells is not fully established. Here, we show that tumor-specific knockdown of carbohydrate sulfotransferase 15 (CHST15), a tumor stromal proteoglycan-synthetic enzyme, suppresses tumor growth in a T-cell-dependent manner in a murine model of PDAC. Silencing of tumoral CHST15 unexpectedly expanded CD4⁺ and CD8⁺ T cells in tumor draining LN (TDLN), leading to accelerated accumulation of EdU⁺ proliferating CD4⁺ and CD8⁺ T cells and granzyme B⁺ CD8⁺ T cells in the tumor. RNA expression analysis indicated that tumoral CHST15 knockdown (KD) downregulated matrix remodeling-related genes, while upregulated anti-tumor T-cell activity-related genes in both tumor and TDLN. CHST15 KD significantly diminished intratumoral and TDLN Ly6C/G⁺ myeloid-derived suppressor cells prior to TDLN T-cell expansion, suggesting that tumoral CHST15 remotely regulated myeloid-derived suppressor cell mediated T-cell suppression in the TDLN. Our findings illustrate a novel immunotherapeutic potential of tumoral CHST15 blockage by reactivating T cells in immune suppressive TDLN of PDAC.     

Impact of the COVID-19 pandemic on pathological autopsy practices in Japan

During the coronavirus disease 2019 (COVID-19) pandemic, autopsies have provided valuable insights into the pathogenesis of COVID-19. The precise effect of this pandemic on autopsy procedures in Japan, especially in instances unrelated to COVID-19, has not yet been established. Therefore, we conducted a questionnaire survey from December 2020 to January 2021 regarding the status of pathological autopsy practices in Japan during the first year of the COVID-19 pandemic. The questionnaire was sent to 678 medical facilities with pathologists, of which 227 responded. In cases where a confirmed diagnosis of COVID-19 was not made at the time of autopsy, many facilities counted them as suspected COVID-19 cases if pneumonia was suspected clinically. At around half of the sites, autopsies were prohibited for suspected COVID-19 cases. In addition, the number of autopsies of non-COVID-19 cases during the pandemic period was also investigated, and a significant decrease was observed compared with the incidence in the pre-pandemic period. The COVID-19 pandemic has affected not only the autopsies of COVID-19 cases but also the entire practice of pathological autopsies. It is necessary to establish a system that supports the implementation of pathological autopsy practices during the pandemic of an emerging infectious disease.     

Molecular basis of carotid body tumor and associated clinical features in Japan identified by genomic,immunohistochemical, and clinical analyses

Carotid body tumor (CBT) is classified as a paraganglioma (PGL). Here, we report the genetic background, protein expression pattern, and clinical findings of 30 Japanese CBT cases. Germline pathogenic or likely pathogenic (P/LP) variants of genes encoding succinate dehydrogenase subunits (SDHs) were detected in 15 of 30 cases (50%). The SDHB variants were the most frequently detected, followed by SDHA and SDHD variants. One case with SDHAF2 variant was bilateral CBT, and other two multiple PGL cases were not detected P/LP variants. The three cases with germline variants that could be tested did not have somatic P/LP variants of the same genes. Immunohistochemical analysis showed negative SDHB signals in CBT tissues in five cases with germline P/LP variants of SDHB, SDHD, or SDHA. In addition, SDHB signals in CBT tissues were negative in four of nine cases without germline P/LP variants of SDHs. These findings suggest the involvement of unidentified molecular mechanisms affecting SDHs.     

Accumulation of L-type Bovine Prions in Peripheral Nerve Tissues

We recently reported the intraspecies transmission of L-type atypical bovine spongiform encephalopathy (BSE). To clarify the peripheral pathogenesis of L-type BSE, we studied prion distribution in nerve and lymphoid tissues obtained from experimentally challenged cattle. As with classical BSE prions, L-type BSE prions accumulated in central and peripheral nerve tissues.     

A comparison of stress relaxation in temporary and permanent luting cements

PurposeThe stress relaxation and compressive strength of resin, resin-modified glass ionomer, glass ionomer, polycarboxylate, and zinc oxide eugenol cements were measured to determine the characteristics of these materials after setting.MethodsA total of 19 luting cements including 12 permanent cements and 7 temporary cements were used. Cylindrical cement specimens (10 mm long and 6 mm in diameter) were obtained by chemical setting or light curing. The specimens were stored for 24–36 h in water at 37 °C and were then used for the stress relaxation and compression tests. The stress relaxation test was carried out using three constant cross-head speeds of 5, 50, and 100 mm/min. Upon reaching the preset dislocation of 0.5 mm, the cross-head movement was stopped, and the load was recorded for 60 s. Fractional stress loss at 1 s was calculated from the relaxation curves. The compressive strength and modulus were measured at a cross-head speed of 1 mm/min. Data were analyzed with the Kruskal–Wallis test and Holm's test.ResultsA zinc oxide eugenol cement [TempBOND NX] exhibited the largest fractional stress loss. A resin cement [ResiCem] showed the largest compressive strength, while a glass ionomer cement [HY-BOND GLASIONOMER CX] showed the largest compressive modulus among all tested cements (p < 0.05).ConclusionThe fractional stress loss could not be classified by the cement type. Two implant cements [Multilink Implant and IP Temp Cement] showed similar properties with permanent resin cements and temporary glass ionomer cements, respectively. Careful consideration of the choice of cement is necessary.     

Evaluation of a latex agglutination method for the rapid identification of Campylobacter jejuni/coli

A latex agglutination assay was developed to identify Campylobacter jejuni and Campylobacter coli. We evaluated the specificity, reproducibility and utility of the assay for clinical use and the following results were obtained. 1) To prepare standardized antigen, bacterial cells must be suspended to a density of 1 to 5 McFarland unit, and heated at 121 degrees C for 10 to 30 min. 2) Bacterial cells may be suspended either in the solution provided with the kit, or in physiological saline, without affecting the results. 3) Of C. jejuni, 94 strains, 6 of C. coli, and 3 of "Campylobacter upsaliensis", all tested positive without exception. All other Campylobacter species, encompassing 13 species and 80 strains, were negative. An additional 9 species and 30 strains, of non-Campylobacter gram negative bacteria, isolated on the Campylobacter selection agar medium, also were uniformly negative. Based on these results, we conclude that bacteria testing positive with the kit can be identified as C. jejuni/coli. Interestingly, "C. upsaliensis", although isolated very rarely from the clinical specimens, also tested positive.     

Novel RASA1 mutations in Japanese pedigrees with capillary malformation-arteriovenous malformation

Capillary malformation-arteriovenous malformation (CM-AVM, MIM#608354) is a rare autosomal dominant disorder characterized by multiple cutaneous capillary malformations co-occurring with fast-flow vascular anomalies, such as arteriovenous malformation or fistula. Despite the identification of RASA1 as the first causative gene in Western patients with CM-AVM, there have been no literature reports of Japanese patients with this gene mutation. We herein report two Japanese pedigrees harboring multiple affected members with CM-AVM. Whole-exome sequencing in the two probands identified novel heterozygous mutations in RASA1, which were co-segregated with the disease in each family and were not reported in large-scale sequencing databases. One was a frameshift mutation and the other a splice-site mutation causing aberrant splicing, confirmed by a minigene assay. There were no other genes commonly disrupted among these probands. RASA1 was a major causative gene even in Japanese patients with CM-AVM, although obvious locus heterogeneity was known for this disease.     

Force-time integral does not improve predictability of cardiac O2 consumption from pressure-volume area (PVA) in dog left ventricle

Summary We have proposed the systolic pressure-volume area (PVA) as a measure of the total mechanical energy generated by ventricular contraction, and we found a closely linear correlation between PVA and cardiac oxygen consumption (V_{O 2}). Although the force-time integral (FTI) has long been considered to be the most reliable correlate of cardiac oxygen consumption (V_{O 2}), we have already shown that V_{O 2} remained constant although FTI was changed while PVA was kept constant in the excised, cross-circulated dog left ventricle. This means that PVA is superior to FTI as a predictor of V_{O 2}. In the present study, we studied whether a linear addition of FTI to PVA could improve the prediction of V_{O 2} from PVA in isovolumic and ejecting contractions with different afterload pressures in the same type of dog left ventricle preparation. Although left ventricular V_{O 2} was always closely correlated with either PVA (r=0.967, mean after z-transformation) or FTI (mean r=0.925), multiple regression analysis indicated that PVA alone accounted for as much as 94% (mean) of the variance of V_{O 2} and that FTI linearly added to PVA accounted for an additional few percent of the variance (statistically significant in less than half the cases). We conclude that the addition of FTI to PVA does not improve the predictability of V_{O 2} from PVA in ordinary contractions.     

A cDNA clone encoding a peptide highly specific for hepatitis C infection

A random primed lambda gtll-cDNA library was constructed from donors plasma presumably infected by blood-borne non-A, non-B hepatitis (hepatitis C:HC) agent and immunoscreened with serum pooled from patients with acute or chronic HC. Twelve lambda gtll-cDNA clones encoding antigens associated with HC infection in Japan as well as in the USA were isolated. Of these one clone consisting of 114 nucleotides and showing a discrete band on an immunoblot analysis, was extensively studied. The clone is not derived from the host DNA encoding one polypeptide specific and highly sensitive for serum from patients with HC and has no homology to the nucleotide sequences of known human viruses including hepatitis A, B and D viruses, Ebstein-Barr virus, coxsackievirus, immunodeficiency virus type 1 or Japanese encephalitis virus. These results suggest that this clone is derived from the genome of HC agent.