A pathological study on the efficacy of Syk inhibitors in a Candida albicans-induced aortic root vasculitis murine model.

BACKGROUND: The activation of innate immunity may be involved in the development of Candida albicans-induced murine vasculitis, which resembles Kawasaki disease (KD) vasculitis. This study aimed to histologically clarify the time course of the development of vasculitis in this model in detail and to estimate the potential role of spleen tyrosine kinase (Syk) inhibitors in KD vasculitis. METHODS AND RESULTS: DBA/2 male mice were intraperitoneally injected with a vasculitis-inducing substance and treated with a Syk inhibitor (R788 or GS-9973). Systemic vasculitis, especially in the aortic annulus area, was histologically evaluated. Regarding lesions in the aortic annulus area, some mice in the untreated control group already showed initiation of vasculitis 1 day after the final injection of a vasculitis-inducing substance. The vasculitis expanded over time. Inflammation occurred more frequently at the aortic root than at the coronary artery. The distribution of inflammatory cells was limited to the intima, intima plus adventitia, or all layers. In the Syk inhibitor-treated groups, only one mouse had vasculitis at all observation periods. The severity and area of the vasculitis were reduced by both Syk inhibitors. CONCLUSION: Candida albicans-induced murine vasculitis may occur within 1 day after the injection of a vasculitis-inducing substance. Additionally, Syk inhibitors suppress murine vasculitis.

Amyand's Hernia diagnosed preoperatively via a CT scan: A case report.

Amyand's hernia is a rare type of inguinal hernia characterized by the presence of the vermiform appendix within the hernia sac. It was named after Claudius Amyand who performed the world's first successful appendectomy on an 11-year-old boy with a right inguinal hernia in 1735 and discovered a herniated appendix during surgery. This condition warrants urgent surgical treatment, with the type of surgical intervention depending on the appendix's condition. However, the nonspecific clinical presentation often complicates the preoperative diagnosis, emphasizing the critical role of imaging in surgical planning. Herein, we present the case of a 74-year-old male who presented with fever, inguinal swelling, and discomfort. Clinical suspicion of inguinal and scrotal inflammation prompted us to perform a prompt CT scan. This radiological evaluation led to a preoperative diagnosis of a Type 3 Amyand's hernia. This case highlights the significance of CT scans in the accurate and timely diagnosis of Amyand's hernia. Distinguishing between various types of Amyand's hernia is pivotal as it profoundly influences surgical decision-making and postoperative outcomes. By sharing this case, we contribute to current knowledge about Amyand's hernia, increase clinical awareness of the condition, and emphasize the crucial role of imaging in its management.

Autopsy report of a sudden infant death that was strongly suspicious of Kawasaki disease.

We conducted an autopsy on a 3-month-old boy in whom Kawasaki disease (KD) was strongly suspected based on the autopsy findings. The infant had a fever and was brought to a nearby clinic, where he was prescribed antipyretics and kept under observation. However, 15 days after onset of the fever, he suddenly died in bed. He exhibited no obvious redness of the lips, tongue, or conjunctiva. Membranous desquamation was present on his distal fingers. Vasculitis was observed in the coronary arteries, renal artery, splenic artery, and pulmonary vein. In addition, coronary artery aneurysms were present in the right coronary artery and left anterior descending artery. Thrombotic occlusion was observed in one aneurysm in the right coronary artery, resulting in acute myocardial infarction. The coronary artery wall showed infiltration of numerous macrophages and neutrophils. This case was classified as incomplete KD because the coronary artery aneurysm could not be demonstrated before death and was only recognized at autopsy. Pathologists and forensic scientists need to be aware that there are cases in which KD goes undiagnosed and untreated, leading to coronary artery aneurysm formation and sudden death.

Thirty-year overview of Japanese autopsy cases of Takayasu arteritis -Results of analysis of Japanese autopsy reports.

OBJECTIVE: To analyze the trends in Takayasu arteritis (TAK) in Japan during three recent decades based on autopsy reports. METHODS: We extracted TAK cases from the Japanese Pathological Autopsy Reports published during three decades (1991-2000, 2001-2010, 2011-2020) and compared the data for the number of cases, age, gender ratio, malignant tumor complication rate, and cause of death (COD). RESULTS: 322 TAK cases were reported during the 30 years. They represented 0.04-0.06% of the total autopsies, with little variation among the three decades. The peak age at autopsy increased over time: from the 60s for 1991-2010 to the 70s for 2011-2020. The malignant tumor complication rate increased to 12.2%, 18.5%, and 22.7% during the three decades. However, about half of those cases had no metastases, and malignant tumors were rarely directly involved in a TAK patient's death. TAK-associated cardiovascular lesions (ischemic heart disease, aortic lesions) accounted for most deaths. CONCLUSIONS: Although the age at TAK onset showed little change during the 30 years, the age at autopsy has increased, suggesting that the long-term prognosis has improved. Although the malignant tumor complication rate increased with age, the most common CODs were cardiovascular lesions, which are prognostic factors for TAK.

Histological studies shed new light on the initiation and characteristics of calcification of coronary artery aneurysms in Kawasaki disease.

BACKGROUND: Calcification of coronary artery aneurysms (CAAs) is common in the remote phase of Kawasaki disease (KD), but the detailed features of its development remain unclear. This study aimed to elucidate the histological characteristics of calcification in KD CAAs. MATERIALS AND METHODS: The study materials consisted of 24 coronary artery branches with aneurysms that were obtained from 14 Japanese patients who died during the period from 40 days to 3 years after the onset of KD. We first examined the CAAs for the presence of thrombi and calcification. When calcifications were observed, we determined their location and shape, and investigated the time-course of the changes based on the time-interval from KD onset until death. Then we measured the area of each calcification and examined for correlations between the calcified area, and (1) the disease duration, and (2) the aneurysm diameter. RESULTS: Calcification was observed in 14 of 24 CAAs (in 7 of 13 LCA and 7 of 11 RCA). Thrombi were also seen in 13 of 14 CAAs with calcification. Calcification showed two localizations: in the organized portion of the thrombus (seen in 12 CAAs) and deep in the thickened tunica of the intima (3 CAAs). The earliest observation of calcification was in an infant who died on the 49th disease day: it was a small, band-shaped calcified lesion in granulation tissue that had formed at the boundary between the thrombus and the blood vessel wall. As the duration of KD increased, the calcified lesion increased in size, and nodular shapes were formed. Moreover, the calcified area tended to increase as the diameter of the aneurysm increased. CONCLUSION: Histologically, CAA calcification starts early in the remote phase of KD, and it is closely related to organization of thrombi.

[Idiopathic esophageal submucosal hematoma during antithrombotic therapy for essential thrombocythemia].

A 73-year-old woman was hospitalized with sudden chest pain and hematemesis. Chest computed tomography and upper gastrointestinal endoscopy revealed an idiopathic submucosal hematoma from the cervical esophagus to the esophagogastric mucosal junction. Idiopathic esophageal submucosal hematoma is often prone to a bleeding tendency of an underlying disorder. The patient had a history of essential thrombocythemia (ET) and was taking aspirin. She successfully recovered after aspirin discontinuation and conservative treatment; however, died of cardiopulmonary arrest in the ward on day 9 of hospitalization. The autopsy revealed that the cause of death was pulmonary thromboembolism. This is the first report of ET with submucosal hematoma of the esophagus. The possibility of an esophageal submucosal hematoma should be considered when patients with ET complain of chest pain since ET and treatment with aspirin are considered risk factors for bleeding. Additionally, close attention should be focused on the risk of developing thrombosis if a patient with myeloproliferative neoplasm is required to discontinue antithrombotic therapy due to a bleeding event.

The pathology of Kawasaki disease aortitis: a study of 37 cases.

BACKGROUND: Kawasaki disease (KD) is a systemic vasculitis syndrome that occurs most frequently in children. Most clinical and pathological studies have focused on its coronary artery lesions. To date, no detailed studies of the aorta have been conducted. We studied KD autopsy cases with the aims of clarifying the time-course of changes in aortic lesions, the differences in the inflammatory cells and degree of inflammation at various aortic sites, and the progression of the inflammation. MATERIALS AND METHODS: The study materials were aortic specimens taken from 37 KD autopsy cases (acute phase: 19; remote phase: 18). Twenty-seven of the cases also had coronary aneurysms. We chose 3 aortic sites, i.e., the thoracic aorta, aortic root and aortic bifurcation, and we histologically observed and compared those sites in regard to the changes with time, the kinds of infiltrating cells and the number of inflammatory cells. We also observed the relationship between the vasa vasorum and inflammatory cell localization in the tunica media, and examined the progression of inflammation in the tunica media. RESULTS: Destruction of the vascular architecture was not seen in any of the 37 cases, but inflammatory cell infiltration was observed in 90% of the acute-phase cases. The inflammatory cell infiltration involved the tunica intima and tunica adventitia of the aorta on the 6th disease-day, and all layers of the aorta on the 13th disease-day; the infiltration peaked on the 18th disease-day. The infiltration gradually disappeared thereafter, and no significant infiltration was seen in the remote phase. The infiltrating inflammatory cells consisted mainly of CD163-positive macrophages. Comparison of the 3 sites of the aorta showed that the inflammatory cell infiltration was more severe in the aortic root and aortic bifurcation than in the thoracic aorta. The progression of inflammation to the aortic tunica media from the adventitia showed 2 patterns: 1 in which macrophages were aggregated around the vasa vasorum; and a second in which there was no such aggregation around the vasa vasorum, but there was diffuse inflammatory cell infiltration of the tunica media. In addition to this, there were findings of direct infiltration of cells from the tunica intima into the tunica media. CONCLUSION: Inflammation in KD occurs in the aorta. The changes with time and the kinds of infiltrating cells were the same as reported to date for coronary arteries in KD. There were differences in the degree of inflammation among the 3 aortic sites. It can be thought that the inflammation from the adventitia to the media progresses via the vas vasorum, and also, there is a possibility of spreading directly. From the intima to the media, inflammation spreads directly. However, formation of aneurysms and destruction of the vascular architecture of the aorta were absent in this study, unlike in coronary arteries.

Recognition of alpha-mannan by dectin 2 is essential for onset of Kawasaki disease-like murine vasculitis induced by Candida albicans cell-wall polysaccharide.

Objectives: Using a murine model of systemic Kawasaki disease (KD)-like vasculitis induced by Candida albicans cell-wall-derived mannan · ß-glucan · protein complexes, the objective was to elucidate the relationships of ß-glucan receptor dectin-1 (D1) and α-mannan receptor dectin-2 (D2) to the onset of that vasculitis.Methods: The incidence and histological severity of vasculitis were compared among mice lacking the genes for D1 or D2 (i.e. D1-/- and D2-/-) and wild-type (WT) mice.Results: The incidences of vasculitis in the three animal groups were 100% (18/18) in the WT group, 100% (18/18) in the D1-/- group, and 0% (0/18) in the D2-/- group. In the WT and D1-/- mice, severe inflammatory cell infiltration, consisting mainly of neutrophils and macrophages, was seen in the aortic root and the coronary arteries. On the other hand, in the D2-/- mice, not even mild vascular lesions such as endoarteritis were seen.Conclusion: Recognition of α-mannan by D2 played an important role in the onset of vasculitis in the studied murine model.

Magnetic Resonance Imaging and Histopathology in a Case of Pleomorphic Adenoma of a Minor Salivary Gland in the Nasal Cavity.

BACKGROUND Pleomorphic adenoma of the salivary gland is a common benign tumor of the parotid gland. However, pleomorphic adenoma arising in the minor salivary glands, including the nasopharynx, is uncommon. This report is of a case of nasal pleomorphic adenoma in which the preoperative imaging findings were consistent with the histological features of pleomorphic adenoma of the minor salivary gland, which differs from that of pleomorphic adenoma of the major salivary gland. CASE REPORT A 56-year-old Japanese man was referred to the department of otolaryngology following nasal endoscopy performed at a referral center that identified a right nasal mass. The findings of contrast-enhanced magnetic resonance imaging (MRI) were consistent with a pleomorphic adenoma arising in the nasal septum. Needle biopsy and histology confirmed the diagnosis of pleomorphic adenoma. The tumor was resected using endoscopic surgery, and the histology confirmed the diagnosis of pleomorphic adenoma covered by normal nasal mucosa. CONCLUSIONS This case showed that pleomorphic adenoma arising in the nasal minor salivary gland had typical MRI and histological findings and was a submucosal lesion. Preoperative MRI supported the approach to surgical resection to ensure complete excision.

Plasmodium RON12 localizes to the rhoptry body in sporozoites.

Invasion of host cells by apicomplexan parasites is mediated by proteins released from microneme, rhoptry, and dense granule secretory organelles located at the apical end of parasite invasive forms. Microneme secreted proteins establish interactions with host cell receptors and induce exocytosis of the rhoptry organelle. Rhoptry proteins are involved in target cell invasion as well as the formation of the parasitophorous vacuole in which parasites reside during development within the host cell. In Plasmodium merozoites, the rhoptry neck protein (RON) complex consists of RON2, RON4, and RON5, and interacts with apical membrane antigen 1 (AMA1) as a critical structure of the invasion moving junction. PfRON12 is known to localize to the rhoptry neck of merozoites, but its function remains obscure. The roles of RON proteins are largely unknown in sporozoites, the second invasive form of Plasmodium which possesses a conserved apical end secretory structure. Here, we confirm that RON12 is expressed in the rhoptry neck of merozoites in rodent malaria parasites, whereas in contrast we show that RON12 is localized to the rhoptry body in sporozoites. Phenotypic analysis of Plasmodium berghei ron12-disrupted mutants revealed that RON12 is dispensable for sporogony, invasion of mosquito salivary glands and mouse hepatocytes, and development in hepatocytes.

Expression of tenascin C in cardiovascular lesions of Kawasaki disease.

BACKGROUND/OBJECTIVE: To examine tenascin C (TN-C) expression in coronary artery lesions (CALs) and myocardial lesions (MLs) in Kawasaki disease (KD). METHODS AND RESULTS: Twenty-five KD autopsy cases (post-KD-onset range of 6 days to 17 years) were examined in this study. Time-course analysis based on the disease day was performed of the histological findings for the CALs and MLs, as well as the localization and intensity of expression of TN-C. TN-C expression was observed to coincide with the areas where inflammatory cell infiltration was present in both coronary arteries and myocardium during the acute stage of KD, and the intensity of its expression correlated with the degree of inflammation. Obvious TN-C expression persisted in the thickened intima and media of CALs even after Disease Day 27. However, in spite of the presence of inflammatory cell infiltration, TN-C expression became weaker in the adventitia and surrounding connective tissue. After 8 months or more, TN-C was not expressed in the vasculitis scars of most cases, but expression was observed around newly formed vessels in the thickened intima and around recanalized vessels after thrombotic occlusion. CONCLUSIONS: The findings suggest a correlation between the degree of inflammation and TN-C expression in the cardiovascular lesions of acute-stage Kawasaki disease.

Ovarian Clear Cell Carcinoma Detected During Long-Term Management of Endometriotic Cysts in Young Patients: Possible Heterogeneity of this Tumor.

Ovarian endometriotic cysts have been identified as the possible origin of ovarian clear cell carcinoma (OCCC), so predicting or preventing future transformation is important. Early detection of clear cell carcinoma is important because it shows low sensitivity to chemotherapy and the prognosis is worse than for other histologic types. We recently treated 2 patients with OCCC. They were both young women with no family history of cancer who received long-term oral contraceptive therapy for endometriotic cysts, and the histologic diagnosis was typical clear cell carcinoma in both patients. However, in Case 1, the tumor was detected by periodic examination, tumor expression of WT1 was positive, and the stage was IA. On the other hand, Case 2 presented with fever of unknown origin, her tumor showed expression of p53, and the stage was IVB. Case 1 is alive with no evidence of disease at 38 months after surgery, while Case 2 died after 19 months despite intensive treatment. These contrasting cases suggest that we need to be aware of the risk of cancer in young women receiving long-term hormone therapy for endometriotic cysts and that OCCC may show greater heterogeneity than what has been reported previously.

Facile Skeletal Rearrangement of Polycyclic Disilenes with Bicyclo[1.1.1]pentasilanyl Groups.

The unexpected formations of fused polycyclic disilenes 2 a and (E),(Z)-3 b by the reduction of the 1,2-dibromodisilanes 5 a (R=Me) and 5 b (R=iPr) bearing bicyclo[1.1.1]pentasilanyl (BPS) groups is reported. The disilenes 2 a and (E),(Z)-3 b were characterized by a combination of NMR spectroscopy and X-ray diffraction analysis (XRD). The reduction of 5 b in the presence of 2,3-dimethyl-1,3-butadiene provided an ene adduct of the disilene 1 b bearing BPS groups, which suggested that an initial product of the reduction of 5 b was the disilene 1 b. Thermal reactions of 2 a and (E),(Z)-3 b afforded the highly strained saturated silicon clusters 4 a and 4 b. A computational study suggested that the transformation of 1 to 2, 3, or 4 can involve silyldisilene-disilanylsilylene rearrangement reactions and insertion reactions of a silylene into a Si-Si bond.

Facile synthesis and bridgehead-functionalization of bicyclo[3.3.3]pentasiloxanes.

A fascinating but still rare bicyclic siloxane, bicyclo[3.3.3]pentasiloxane, was synthesized by the oxidation of a bicyclic silicon cluster and characterized using a combination of NMR spectroscopy and X-ray diffraction analysis. The bridgehead OSiMe3 groups of the siloxane were selectively and efficiently converted to O-K+ (siloxide) by treating with tBuOK in the presence of 18-crown-6-ether. The resulting siloxides provided various bridgehead-functionalized bicyclo[3.3.3]pentasiloxanes after treatment with electrophiles.

Histopathological aspects of cardiovascular lesions in Kawasaki disease.

Kawasaki disease (KD) is the commonest vasculitic syndrome. It affects medium-sized arteries, principally the coronary arteries. Histologically, coronary arteritis begins at 6 to 8 days after the onset of KD and the inflammation rapidly involves all layers of the artery. This results in severe damage to the structural components of the artery leading to arterial dilation. The inflammatory infiltrate in KD arteritis is characterized predominantly by infiltration of monocytes and macrophages. Activated neutrophils, monocytes and macrophages are believed to be involved in the initial stage of coronary arteritis. Inflammatory cell infiltration may continue for up to 25 days of disease following which the inflammatory cells gradually decline in number. Inflammatory lesions in the arteries are relatively synchronous as they evolve from an acute to the chronic stage. If a giant aneurysm remains or vessel recanalization occurs after thrombotic occlusion of an aneurysm, the remodeling of vascular structures may continue for a much longer time.