Mediastinal hematoma as an unusual intrathoracic manifestation of Boerhaave Syndrome: A case report

INTRODUCTION

Boerhaave Syndrome (BS) is rare but life-threatening condition caused by a sudden increase in the intraluminal pressure due to vomiting. We present a case of BS manifesting as a posterior mediastinal hematoma, indicative of a potentially fatal condition.

PRESENTATION OF CASE

A 51-year-old man presented with acute chest pain after vomiting. Enhanced Computed Tomography revealed mediastinal fluid with a left pleural effusion, leading to a diagnosis of BS. Emergency surgery revealed a posterior mediastinal hematoma with active bleeding due to a torn proper esophageal artery. Hemostasis and a wall repair were performed, and the patient was discharged uneventfully.

DISCUSSION

This case highlights two important aspects. Firstly, a spontaneous esophageal perforation can manifest as a mediastinal hematoma due to the subpleural arterial injury, delaying bacterial spillage. While preoperative thoracentesis may not always diagnose BS accurately, bloody thoracic drainage can serve as an alternative diagnostic sign. Secondly, the mediastinal hematoma itself poses a serious risk, as it can lead to a catastrophic outcome even before bacterial contamination occurs, emphasizing the necessity of a timely surgical intervention in BS cases.

CONCLUSION

BS can manifest as a mediastinal hematoma, and the absence of gastrointestinal content in the thoracic drainage does not rule out the possibility of BS. Prompt surgical intervention remains essential, as a mediastinal hematoma alone can result in a catastrophic outcome. This case highlights the significance of a comprehensive diagnostic assessment for BS.

Evaluation of the widths of the mucosal strips in pathological examination of specimens of endoscopic submucosal dissection for early gastric cancer

BACKGROUND

Endoscopic submucosal dissection (ESD) is the standard treatment for early gastric cancer in Japan. Pathological evaluation of ESD specimens is considered essential to determine if additional gastrectomy is necessary. Usually, specimens resected by ESD are sliced into 2-3 mm wide sections, and each section is examined for depth of tumor and lymphovascular invasion. Nevertheless, in most cases of additional gastrectomy, lymph node metastasis is not present. Given that there are few-studies on how clinical-decisions based on the pathologic-evaluation-method, in particular the specimen cut-width, influence patient outcomes, we retrospectively evaluated whether reducing the number of cuts to one-half or one-third would result in underestimation of the real need for additional surgery. The effect of the actual cut-width on recommended treatment (referral to operation) and patient-outcomes was also assessed.

METHODS

Pathological records of 498 lesions from 439 patients were reviewed and re-evaluated. All pathological descriptions are based on the gastric cancer classification system of the Japanese Gastric Cancer Association, 15th edition.

RESULTS

In 5.8% and 8.5% of the total specimens, underdiagnosis of tumor-depth and lymphovascular invasion occurred when the number of sections was reduced to one-half and one-third, respectively. Significantly more submucosal invasions were found in the group in which the cut-with was between 3 and 4 mm than in the group in which the cut width was less than 3 mm.

CONCLUSION

Evaluation of the appropriate cut-width is important and should be discussed from the standpoint of labor costs and lost opportunities to search for molecular markers in ESD materials.

[A Case of Robot-Assisted Conversion Surgery for Gastric Cancer with Peritoneal Dissemination That Responded to Intravenous and Intraperitoneal Paclitaxel Combined with S-1 Chemotherapy]

This case involved a 69-year-old female patient with peritoneal dissemination of an advanced gastric cancer. She underwent chemotherapy comprisingintravenous and intraperitoneal paclitaxel combined with S-1. After 20 courses, a staging laparoscopy was performed, and pathological analysis of the peritoneal dissemination and cytologic analysis of ascites fluid yielded negative results. A radical robot-assisted total gastrectomy was successfully performed. The pathological stage was determined to be ypT4aN2M0, ypStage ⅢB. We continued to administer the same chemotherapy regimen for 15 courses (total: 35 courses)after surgery. No recurrence has been detected during the 1-year period after surgery.

[A Case of Duodenal Gastrointestinal Stromal Tumor Resection with Preservation of the Pancreatic Head Following Chemotherapy with Imatinib]

A 60-year-old male was admitted to our hospital on account of a duodenal submucosal tumor on the opposite side of Vater's papilla identified on a screening gastroduodenoscopy. The tumor was diagnosed as a duodenal gastrointestinal stromal tumor(GIST)due to positive c-kit and DOG1tests. Gastroduodenography and enhanced computed tomography showed a 50mm tumor widely invadingthe descendingportion of the duodenum close to the papilla of Vater and indicated the need for extended resection includingpancreaticoduodenectomy to achieve curation. Preoperative chemotherapy was initiated with imatinib mesylate(imatinib)to preserve the pancreas. A 16 month course of imatinib shrunk the tumor up to 21mm and laparoscopic partial duodenectomy was performed as a curative resection. So far, no local tumor recurrence has been seen for 26 months after the surgery. Herein, we report this case with a review of the literature.

Aralin, a type II ribosome-inactivating protein from Aralia elata, exhibits selective anticancer activity through the processed form of a 110-kDa high-density lipoprotein-binding protein: a promising anticancer drug

Aralin from Aralia elata is a newly identified type II ribosome- inactivating protein, which preferentially induces apoptosis in cancer cells. In this study, we identified that the aralin receptor is a 110-kDa high-density lipoprotein-binding protein (HDLBP), which functions as a HDL receptor. The sensitivities of tumor cell lines to aralin were dependent on the expression levels of the 110-kDa HDLBP and its forced expression in aralin-resistant Huh7 cells conferred aralin sensitivity. HDLBP-knockdown HeLa cells showed a significant aralin resistance in vitro and in vivo. Conversely, ectopic expression of the 150-kDa HDLBP resulted in increased aralin sensitivity in vivo, accompanying enhanced expression of the 110-kDa HDLBP. Thus, these results showed that the 110-kDa HDLBP in lipid rafts acted as an aralin receptor and that its expression levels determined aralin sensitivity, suggesting that aralin could be a promising anticancer drug for HDLBP-overexpressing tumors.

Production of aralin, a selective cytotoxic lectin against human transformed cells, in callus culture of Aralia elata

Recently we found that aralin, a novel lectin, from Aralia elata selectively induces apoptosis in human virus-transformed and cancer cells compared with normal cells. To overcome the reduction of aralin biosynthesis according to the development of leaves, we established callus tissues from the young shoots. The N-terminal amino acid sequence and immunochemical analyses revealed that ca-aralin, an aralin synthesized in the callus, was structurally identical with aralin except for the glycosylation of the B chain. The selective cytotoxic index (ratio of IC50 value against human lung normal cells versus virus-transformed cells) of ca-aralin was 2-fold higher than that of aralin. Thus, these results suggest that ca-aralin is more useful than aralin as an anticancer agent.

Inhibitory profile of nonapeptide derived from porcine troponin C against angiotensin I-converting enzyme

A novel angiotensin I-converting enzyme (ACE) inhibitory peptide (RMLGQTPTK; 9mer) from porcine skeletal troponin C was investigated for its inhibitory profile. This peptide was noncompetitive and as hydrophobic as the known ACE inhibitory peptides. Aminopeptidase M quickly hydrolyzed 9mer, resulting in production of MLGQTPTK and LGQTPTK with inhibitory activities similar to those of 9mer. The main hydrolysis product of 9mer with carboxypeptidase A and B was RMLGQTPT showing very weak activity. Most products derived from 9mer hydrolysis by ACE, aminopeptidase, or carboxypeptidase showed weak but definite ACE inhibitory activities. Thus, 9mer was estimated to be a wholly efficient inhibitor with these fragment peptides.

An apoptotic inducer, aralin, is a novel type II ribosome-inactivating protein from Aralia elata

We recently found that aralin, a novel cytotoxic protein consisting of two subunits, from Aralia elata selectively induces apoptosis in transformed cells as compared to normal cells. Here we report that aralin is a lectin specific for galactose (Gal) and its derivatives, and possesses RNA N-glycosidase activity as a new type II ribosome-inactivating protein (RIP). The RNA N-glycosidase activity of aralin was detected in cell-free and whole cell systems by the generation of an R-fragment from 28S rRNA. Coinciding with appearance of the R-fragment in aralin-treated cells, significant inhibition of protein synthesis was observed prior to the onset of apoptosis. Aralin-evoked cell death was efficiently repressed by the addition of Gal and its derivatives. Interestingly, melibiose preferentially protected normal cells from apoptosis as compared with transformed cells. Using rhodamine-coupled aralin, the aralin receptor could be clearly detected around the cell surface of transformed cells, but to a lesser extent on normal cells. Receptor binding was suppressed by Gal. These results indicate that aralin is incorporated into cells via its Gal-containing cell surface receptor and induces apoptosis through its RIP activity. Moreover, the expression level and/or structural changes of the aralin receptor may affect the sensitivity toward aralin.

Aralin, a new cytotoxic protein from Aralia elata, inducing apoptosis in human cancer cells

In this study, we purified a novel cytotoxic protein, aralin, from the shoots of Aralia elata. Aralin is composed of two subunits, A and B chains whose molecular weights are 29,100 and 32,200, respectively. In the assay using a normal human lung fibroblast cells (WI-38) and its SV40-transformed cells (VA-13), aralin demonstrated selective cytotoxicity against the virus-transformed cell line; the IC50 values of WI-38 and VA-13 were 10 and 0.8 ng/ml, respectively. Aralin showed positive response to DNA fragmentation in human lymphocyte HL-60 cells, and caspase specific inhibitors suppressed aralin-induced DNA fragmentation. These results indicate that the cytotoxicity of aralin is brought about primarily through the induction of apoptosis. Aralin also exhibited potent cytotoxic activity against various types of human cancer cell lines; cervical carcinoma cells (HeLa) proved the most sensitive, with an IC50 value of 0.08 ng/ml.

Effects of nucleotides on N-acetyl-d-glucosamine 2-epimerases (renin-binding proteins): comparative biochemical studies

Renin-binding protein (RnBP) is an endogenous renin inhibitor originally isolated from porcine kidney as a complex of renin, so-called high molecular weight (HMW) renin. Our recent studies demonstrated that human RnBP is the enzyme N-acetyl-D-glucosamine (GlcNAc) 2-epimerase [Takahashi, S. et al. (1999) J. Biochem. 125, 348-353]. We have purified recombinant human, rat, and porcine RnBPs expressed in Escherichia coli JM 109 cells. The purified recombinant RnBPs existed as dimers and inhibited porcine renin activity strongly. On the other hand, porcine renin inhibited recombinant GlcNAc 2-epimerase activities. The human GlcNAc 2-epimerase activity could not be detected in the absence of a nucleotide, whereas ATP, dATP, ddATP, ADP, and GTP enhanced the human GlcNAc 2-epimerase activity. Other nucleotides had no effect on human GlcNAc 2-epimerase activity. Rat and porcine GlcNAc 2-epimerases were activated by several nucleotides. Nucleotides that enhance the activity of GlcNAc 2-epimerases protect these enzymes against degradation by thermolysin. These results indicate that mammalian RnBPs have GlcNAc 2-epimerase activity and that nucleotides are essential for formation of the catalytic domain of the enzyme.

Modulation of the immune response to tumors by a novel synthetic compound, (4R)-3-benzoyl-N-[(1R)-1-phenylethyl]-4-thiazolidinecarboxamide (RS-0481)

RS-0481, (4R)-3-benzoyl-N-[(1R)-phenylethyl]-4-thiazolidinecarboxamide, is a compound that can re-establish the function of certain lymphoid cell populations impaired by the presence of a growing tumor in an animal. The compound markedly augmented the tumor-specific cytotoxic T lymphocytes, TDTH (delayed-type hypersensitivity T cells), and the nonspecific lymphokine-activated-killer-cell-like cell responses. It also enhanced the tumor-inhibitory effect of macrophages in tumor-bearing mice, but not in normal mice, indicating that it enhances the antitumor immune responses. Lymphocytes from RS-0481-treated tumor-bearing mice released significantly higher amounts of macrophage-activating factor(s) (MAF) and interleukin-2(IL-2)-like factors in culture compared with lymphocytes from untreated animals. Also, sera from treated tumor bearers showed elevated colony-stimulating factor (CSF) activity. Although the compound did not influence the factor-producing activity in mice without tumor, it enhanced the responsiveness of their bone marrow cells, T cells, and macrophages to CSF, IL-2, and MAF. It seems therefore possible that the compound enhances the responsiveness of immunocompetent cells to cytokines, resulting in a marked augmentation of antitumor T cell responses in tumor-bearing mice. Consistently it inhibited the development of lymph node metastasis of transplanted X5563 plasmacytoma, and we showed that T cells play a decisive role in this inhibition. The compound also counteracted the development of suppressor T cell activity in the spleen of tumor-bearing mice.

Postnatal transformation and location of mitoses in the epithelium lining the mouse vomeronasal organ

The structure and the postnatal transformation of the epithelium lining the vomeronasal organ of the mouse was observed. The medial wall of the middle segment of the organ was lined with the sensory epithelium similar to the olfactory epithelium, and was not undergone any transformation in the postnatal life. The lateral wall of the middle segment and the entire lumen of the rostral segment were covered with the stratified cuboidal epithelium in the newborn mouse. The stratified cuboidal epithelium transformed into the ciliated columnar epithelium with advancing ages, excepting in the vomeronasal duct where the epithelium changed into the stratified squamous one. In the mouse aged between 4 and 10 days, mitotic figures were observed not only in the boundary between the sensory epithelium and the ciliated columnar one in the middle segment, but also in the rostral segment of which the entire lumen was covered with the ciliated columnar epithelium.