Appendiceal neurofibroma with low-grade appendiceal mucinous neoplasm in neurofibromatosis type 1 patient: A case report

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Appendiceal neurofibromas (AN) in Neurofibromatosis type (NF) 1 are rare.

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AN in NF1 with Low-grade appendiceal mucinous neoplasms (LAMNs) are extremely rare.

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AN and LAMNs have potential for malignant transformation.

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Surgical resection is the standard treatment for patients with AN and LAMNs.

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However, appropriate surgical procedure remains controversial.

Introduction

Neurofibromas are a characteristic of the autosomal dominant disorder Neurofibromatosis type 1 (NF1), also known as von Recklinghausen’s disease. Appendiceal neurofibromas are extremely rare, and low-grade appendiceal mucinous neoplasms (LAMNs) have not previously been reported in NF1.

Presentation of case

A 62-year-old man with NF1 was scheduled for elective surgical treatment of an asymptomatic, enlarged and diffusely thickened appendix that remained after curative antimicrobial treatment of acute appendicitis. Laboratory analysis revealed all normal. Colonoscopy showed thickened appendiceal mucosa projecting into the cecum. A sample of the mucosa was found to be pathologically benign. The patient was preoperatively diagnosed with treated acute appendicitis with chronic appendiceal inflammation versus appendiceal neoplasms. Laparoscopic cecectomy was performed. Multiple neurofibromas were observed in the muscle layer, submucosa, and mucosa of the appendix on histopathological examination. Immunohistochemical examination showed positive staining for S-100. Pathologically, the patient was diagnosed with appendiceal neurofibroma consistent with NF1 with LAMNs. His postoperative course was unremarkable. He was discharged on post-operative day 3 and remained in good health 7 month after surgery.

Conclusions

Appendiceal neurofibromas are often preoperatively diagnosed as appendicitis. Appendiceal neurofibromas should be considered in patients with NF1 who are suspected of having appendicitis.

Intestinal obstruction caused by low-grade appendiceal mucinous neoplasm: A case report and review of the literature

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Intestinal obstructions caused by external compression from the appendix are rare.

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Low-grade appendiceal mucinous neoplasm (LAMN) with torsion is rarer still.

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LAMN have the potential to lead to pseudomyxoma peritonei.

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Surgical resection for LAMN is the standard treatment.

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The appropriate surgical procedure, however, remains controversial.

Introduction

Intestinal obstructions due to appendiceal pathology are rare. Obstructions caused by low-grade appendiceal mucinous neoplasms (LAMNs) are rarer still.

Presentation of case

A 79-year-old woman was referred to our hospital for mechanical small intestinal obstruction. The patient had undergone prior left oophorectomy via a lower abdominal incision. Physical examination revealed abdominal distension and slight tenderness. Laboratory analysis was unremarkable. Contrast enhanced computed tomography (CT) demonstrated dilation of an obstructed small intestinal loop without evidence of strangulation. There appeared to be a low density mass measuring 3.0 × 1.5 cm with a potential twist in the mesentery near the transition point in the small intestine. The patient was diagnosed with mechanical small intestinal obstruction and was treated conservatively with nasogastric tube decompression for one week. After no clinical improvement, we elected to surgically explore her. Intraoperative findings revealed that the ileum was compressed by the appendix, which had a cystic mass on its tip. There was no evidence of intestinal ischemia. Laparotomy appendectomy alone was performed. Pathology revealed a LAMN measuring 3.0 × 1.5 cm. She remains disease-free with 18 months of postoperative follow-up.

Discussion

Intestinal obstruction due to external compression by an appendiceal mass is rare, and is often difficult to preoperatively diagnose with CT.

Conclusions

The etiology of small intestinal obstruction with a transition point in the right lower quadrant of abdomen includes an appendiceal mass on the broad differential for this common problem.

Pancreatobiliary fistula associated with intraductal papillary mucinous carcinoma accompanying obstructive jaundice: A case report

INTRODUCTION

Intraductal papillary mucinous neoplasms (IPMNs) occasionally involve formation of fistulas with other adjacent organs. Pancreatobiliary fistulas associated with IPMNs are rare, but affected patients often develop obstructive jaundice and cholangitis.

PRESENTATION OF CASE

A 79-year-old man was referred to our hospital for evaluation of abnormal biliary enzymes. Contrast-enhanced computed tomography and endoscopic retrograde cholangiopancreatography demonstrated multiple cystic lesions with septa in the pancreatic head and fistulas between the cystic lesions and common bile duct. The clinical diagnosis was pancreatobiliary fistula associated with a mixed-type IPMN and accompanying obstructive jaundice. The patient underwent subtotal stomach-preserving pancreaticoduodenectomy. The resected specimen showed fistulas between the cystic lesions and common bile duct. Histopathological examination showed that the main and branch ducts of the pancreatic head were dilated and filled with mucus. The epithelia of the pancreatic ducts revealed papillary proliferation and an invasive adenocarcinoma arising from an intraductal neoplasm. Immunohistochemistry examination showed CDX2- and MUC2-positive reactions. The final diagnosis was an intraductal papillary mucinous carcinoma of the intestinal-type. The patient remained disease-free for 9 months postoperatively.

DISCUSSION

The causes of death in patients who have pancreatobiliary fistulas associated with IPMNs without resection are cholangitis or hepatic insufficiency. Nonoperative treatment is limited for cases with obstructive jaundice. It is necessary to prevent obstructive jaundice and cholangitis due to a large quantity of mucinous material.

CONCLUSIONS

Surgical resection should be considered, if possible, in patients with pancreatobiliary fistulas associated with IPMNs. A better prognosis is expected with prevention of obstructive jaundice or cholangitis.

Splenic hamartoma associated with thrombocytopenia: A case report

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Few cases of splenic hamartomas associated with thrombocytopenia have been reported.

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Imaging findings in splenic hamartomas are non-specific, variable, and making definitive preoperative diagnosis difficult.

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Surgery is necessary for diagnosis when malignancy cannot be ruled out.

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Surgery may also improve symptoms of hypersplenism, including thrombocytopenia.

Introduction

Hamartomas are rare, benign tumors of the spleen. Few cases of splenic hamartomas associated with thrombocytopenia have been reported.

Presentation of case

An asymptomatic 64-year-old man with myelodysplastic syndrome was found to have a splenic tumor. Laboratory tests were significant for thrombocytopenia, with a platelet count of 7.8 × 10⁴/μL. Ultrasonography showed splenomegaly (10.8 × 6.6 cm), and a hypoechoic splenic mass (8.0 × 7.0 cm). Color doppler ultrasound revealed blood flow within the mass, and the mass density was homogeneous on abdominal computed tomography (CT). Contrast-enhanced CT showed heterogeneous enhancement of the splenic mass during the arterial phase. Positron emission tomography (PET)-CT showed no significant fludeoxyglucose (FDG) accumulation within the mass. The differential diagnosis included splenic hamartoma, splenic hemangioma, splenomegaly associated with extramedullary hematopoiesis, and malignant tumor, including solitary splenic metastasis. A laparoscopic splenectomy was performed due to the possibility of malignancy, the presence of thrombocytopenia, and the risk of splenic rupture. The resected specimen showed a localized, well-demarcated, 8.0 × 7.0 cm splenic mass. Histological examination revealed abnormal red pulp proliferation and the absence of normal splenic structures. The patient’s post-operative course was uneventful. His platelet count improved on post-operative day 1 and he was discharged on post-operative day 9. He remained in good health with a normal platelet count one month after surgery.

Discussion

Making definitive preoperative diagnosis is difficult in splenic hamartomas. Surgery is necessary for diagnosis when malignancy cannot be ruled out.

Conclusions

Surgery may also improve symptoms of hypersplenism, including thrombocytopenia.

Topologically protected surface states in a centrosymmetric superconductor β-PdBi2

The topological aspects of electrons in solids can emerge in real materials, as represented by topological insulators. In theory, they show a variety of new magneto-electric phenomena, and especially the ones hosting superconductivity are strongly desired as candidates for topological superconductors. While efforts have been made to develop possible topological superconductors by introducing carriers into topological insulators, those exhibiting indisputable superconductivity free from inhomogeneity are very few. Here we report on the observation of topologically protected surface states in a centrosymmetric layered superconductor, β-PdBi₂, by utilizing spin- and angle-resolved photoemission spectroscopy. Besides the bulk bands, several surface bands are clearly observed with symmetrically allowed in-plane spin polarizations, some of which crossing the Fermi level. These surface states are precisely evaluated to be topological, based on the Z₂ invariant analysis in analogy to three-dimensional strong topological insulators. β-PdBi₂ may offer a solid stage to investigate the topological aspect in the superconducting condensate.

Materials possessing topologically non-trivial electronic surface states are predicted to host exotic Majorana fermion excitations in the superconducting state. Here, the authors demonstrate the existence of topologically-protected surface states in the centrosymmetric layered superconductor β-PdBi2.

[A case of advanced gastric cancer with multiple liver metastases completely responding long term to paclitaxel plus S-1 therapy]

A 69-year-old man was admitted to our hospital with complaints of loss of appetite, fatigue and dysphasia. Upper gastroscopy revealed advanced gastric cancer. Abdominal CT suggested liver metastases. At first we thought the liver metastases has been completely resected, but we found multiple liver metastases unexpectedly. So only total gastric resection and liver biopsy were performed. The pathological diagnosis was metastatic carcinoma. Paclitaxel (PTX) and S-1 combination chemotherapy was started after operation and was continued for 42 courses. A CT scan showed a complete response, and he has been well without tumor re-growth ever since. The combination of PTX and S-1 not only may be an effective regimen for gastric cancer with liver metastases, but also can be used without side effects for a long time.

In vitro drug-drug interaction studies with febuxostat, a novel non-purine selective inhibitor of xanthine oxidase: plasma protein binding, identification of metabolic enzymes and cytochrome P450 inhibition

1. The potential for drug-drug interactions with febuxostat was examined in the following three in vitro systems: the characteristics of the binding of febuxostat to human plasma proteins; identification of the cytochrome P450 (CYP) and UDP-glucuronosyltransferase (UGT) enzymes participating in the metabolism of febuxostat; and the potential inhibitory effects of febuxostat on typical CYP reactions. 2. The results have shown that the presence of ibuprofen or warfarin did not change the plasma protein binding of febuxostat, and that febuxostat did not influence the plasma protein binding of ibuprofen or warfarin. These results indicate that there is little possibility that febuxostat causes a drug-drug interaction by binding to albumin. 3. The UGT 1 and 2 families were involved in the glucuronidation, and several CYPs participated in the metabolism of febuxostat, suggesting that there is little possibility that the blood concentration of febuxostat varies widely even if febuxostat is concomitantly administered with drugs that inhibit CYP or UGT enzyme. Examination of the inhibitory effect of febuxostat on CYP enzymes suggests that febuxostat minimally inhibits the activities of any CYP. 4. The results demonstrate that febuxostat is a novel anti-hyperuricaemia drug with low drug-drug interaction potential in clinical use.

A case of secondary diabetes mellitus with acromegaly improved by pioglitazone

AIM

The acromegaly patient was diagnosed with Type 2 diabetes mellitus. His HbA1c was 10.6% and fasting blood glucose (FBG) 15.3 mmol/l. We prescribed glibenclamide (10 mg/day), but his HbA1c and FBG remained high. At this stage, treatment with short-acting insulin was instigated at a dose of 20 U/day. However, the patient's blood glucose level remained unsatisfactory. We tried using pioglitazone.

METHOD

Pioglitazone was prescribed at 30 mg/day in combination with the insulin.

RESULTS

The FBG and HbA1c value decreased to 7.2 mmol/l and 7.3%, respectively, within 2 months and insulin was discontinued. Pioglitazone alone was able to control the FBG level.

CONCLUSIONS

Pioglitazone treatment might be considered as a choice for similar cases of diabetes secondary to acromegaly.

Pathological change of articular cartilage in the mandibular head treated with immunosuppressant FK 506

While several reports have documented immunosuppressant-induced osteoporosis, the exact mechanism of the pathological change of the joint remains to be clarified. In the present study, we have demonstrated the pathological change of the articular cartilage in the mandibular head of five Sprague-Dawley rats administered with the immunosuppressant FK 506 for 28 days. Three-dimensional micro-computed tomography of the mandibular heads in treated rats showed a significant decrease in trabecular bone volume compared to control rats. Histological observation revealed atrophic change of the articular cartilage. Immunohistological observation using anti-proliferative cell nuclear antibody (PCNA), type I, II, and type X collagen antibodies showed significantly decreased proliferation and differentiation of chondrocytes in the articular cartilage compared with the control group (p<0.05). Tartrate-resistant acid phosphatase (TRAP) staining revealed no significant difference in the numbers of osteoclasts at the chondro-osseous junction. Thus, FK 506 administration inhibited chondrogenic cell proliferation and differentiation and might cause osteoporotic change of subcartilage trabecular bone that subsequently forms in the mandibular head.

Development of a quantification system of ionic dissociative metabolites using an FT-IR/ATR method

A simultaneous quantification system of ionic dissociative metabolites was developed using a Fourier transform mid-infrared spectroscopic method by focusing our attention on the enzyme reaction from glucose 6-phosphate to fructose 6-phosphate with phosphoglucose isomerase (PGI). We studied the pH dependency of the infrared spectra of the mixture solution for which the PGI reaction was assumed. The infrared spectra of ionic dissociative components in the mixture solution were extracted by multiple linear regression analysis under the assumption of ionic dissociation equilibrium. Additionally, we constructed a simultaneous quantification system using the extracted spectra of the ionic dissociative components on the basis of the ionic dissociation equilibrium. We could accurately estimate the pH value and the concentrations of the ionic dissociative materials in their mixture solution by using this quantification system. In addition, the stability of quantification results for a pK shift was also verified.

Extensive primary repair of the thoracic aorta in Stanford type A acute aortic dissection by means of a synthetic vascular graft with a self-expandable stent

OBJECTIVES

To minimize any residual false lumen when operating on patients with an acute type A aortic dissection, we tried to perform extensive primary repair of the thoracic aorta with the modified elephant trunk technique. The early and midterm results of these surgical interventions are reported and evaluated.

METHODS

Among the acute type A aortic dissections with extensive false lumen encountered since December 1997, 19 consecutive patients, 15 DeBakey type I with the tear in the ascending, transverse, or both aortas, and 4 DeBakey type III-D with the tear located in the descending aorta, underwent insertion of a synthetic graft with a distally anchored stent in the descending thoracic aorta. The interpolation method was used as an introducer combined with total replacement of the aortic arch by using a synthetic branching graft with only a median sternotomy.

RESULTS

One patient died, and 18 were discharged after full recovery. Postoperative computed tomographic scans showed that no residual false lumina were present proximal to the diaphragmatic level, and no false lumina were found in 10 patients. Two patients with acute ischemia of the right kidney caused by narrowing of the true lumen, as demonstrated by radiographic computed tomography, improved significantly after surgical intervention with restoration of blood flow in the true lumen. Paraplegia was not observed in any patient.

CONCLUSIONS

In emergency operations for an acute type A aortic dissection, the operation is often limited to replacing the ascending aorta because priority is given to saving the patient's life. However, it is possible to perform extensive primary repair of the thoracic aorta with relative safety by interpolating a synthetic graft with a self-expandable stent.

Repair of the thoracic aorta by transaortic stent grafting (open stenting)

BACKGROUND

The late results of direct open stent grafting of the aortic arch for aortic arch repair have not been reported previously.

METHODS

Between September 1997 and December 2000 19 patients underwent open stent grafting with carotid artery bypass for thoracic arteriosclerotic aneurysms (TAA) of the distal aortic arch. In addition, 21 patients underwent open stent grafting with total aortic arch replacement for Stanford type A acute aortic dissection and 7 patients underwent stenting with carotid bypass for Stanford type B chronic aortic dissection.

RESULTS

The early mortality rate was 11% for TAA, 10% for type A dissection, and 0% for type B dissection. Whereas none of the TAA or type A dissection required a second operation on the thoracic aorta, 1 TAA patient died 6 months postoperatively after sudden aortic rupture and 1 type B patient required descending aortic replacement because of ulceration caused by the stent graft at 11 months postoperatively. On follow-up computed tomography scan, in TAA patients, true aneurysms excluded by the stent graft showed early thrombosis, but the absorption of thrombosed aneurysms started from 1 to 6 months postoperatively and gradually progressed. In patients with type B chronic dissection, the false lumen showed early thrombosis and the true lumen was dilated at the central portion of the graft, which might increase turbulent flow by interaction with the stent. In patients with type A acute dissection, the false lumen showed both early thrombosis and early absorption.

CONCLUSIONS

Early and late results of open stenting are acceptable and follow-up computed tomography scan may be able to predict late results of open stenting.

[Hepatitis C virus genotyping by restriction fragment length polymorphism of polymerase chain reaction products generated with a HCV detection kit]

Highly conserved sequence in the 5' untranslated region(UTR) of hepatitis C virus(HCV) genome have been targeted by most nucleic acid amplification-based detection assays, such as Amplicor HCV test, a commercially available assay kit. In this study, we classified HCV genotypes by direct sequencing determination for 5' UTR of nested-PCR after Amplicor HCV test. Then, based on the results of sequence, RFLP analysis after digestion of the nested PCR fragments with Hae III or Sau 3AI to classify HCV genotype was evaluated. RFLP analysis distinguished the type 1, 2a and 2b. Only one of 29 samples was not classified by RFLP analysis due to the point mutation of Hae III recognition site. HCV genotypes commonly found in JAPAN were classified into three types, 1b, 2a, and 2b. Also, RFLP analysis requires fewer resources than serotype grouping test. Hence, the present method provides an adaptable and rapid HCV genotyping in clinical laboratory in JAPAN.

Radical-capturing reaction of 5,7,3',4'-tetramethylquercetin with the AIBN radical initiator

In order to clarify the mechanism for the radical-capturing reaction which is initiated at the C3-hydroxyl group of flavonols, 5,7,3',4'-tetramethylquercetin (TMQ) was reacted with the 2,2'-azobis-isobutyronitrile (AIBN) radical initiator in benzene. Six products, one depside and its two hydrolytic products, one nitrile adduct, and two others, were isolated from the reaction mixture, and their structures were determined by instrumental analyses. The quantitative change to the four main products against the reaction time was measured by an HPLC method. The radical-capturing reaction pathway for TMQ with AIBN is proposed from these products and their quantitative changes. The pathway dividing into two clearly reveals that one subpath formed the depside and its hydrolytic products, while the other formed the nitrile adduct. The reactivity of each two sub-path was nearly the same, different from the case of TMQ and the 2,2'-azobis-2,4-dimethylvaleronitrile (AMVN) radical initiator.

Syringomatous adenoma of the nipple: report of a case

We report herein a rare case of syringomatous adenoma (SA) of the nipple. Only 22 cases of SA of the nipple have been documented in the world literature, and to the best of our knowledge this is the first case to be reported in Japan. The patient was a 68-year-old woman who presented with a painful mass in the right subareolar region of over 15 years' duration. Clinical examination including needle biopsy indicated a high possibility of carcinoma; however, the final histopathological diagnosis after mastectomy proved to be SA. SA is a benign locally infiltrating neoplasm of the nipple which shares many clinicopathological features with adenoma of the nipple. Both lesions sometimes show deceptive clinicopathological findings, causing then to be easily confused with carcinomas. However, SA can be distinguished by its unique histological appearance resembling sweat duct, or syringomatous, tumors and locally infiltrating growth, which is probably responsible for its misleading clinical findings and higher rate of recurrence. Surgeons should be aware of the possibility of diagnosing this extremely rare tumor, and the appropriate treatment.

Cardiovascular effects of NT-1, a new patch form of nitroglycerin, alone and in combination with nifedipine in conscious dogs

The cardiovascular effects of NT-1, a new patch form of nitroglycerin, alone and in combination with nifedipine in conscious dogs were examined. NT-1 (2.5 mg kg-1 nitroglycerin) decreased systolic blood pressure by 10-15%, while diastolic blood pressure and heart rate were not affected. Coronary blood flow and calculated rate-pressure product were decreased. These parameter changes occurred at 30 min after NT-1 application and remained constant for 8 h until NT-1 was removed. After administration of NT-1 in combination with nifedipine, systolic blood pressure was significantly decreased to a greater extent, and heart rate and coronary blood flow showed a tendency to increase compared with nifedipine alone. Rate-pressure product was not changed compared with that obtained on administration of nifedipine alone. These results suggest that NT-1 may be applicable as a transdermal sustained release medication, and show that in combination with nifedipine, NT-1 can induce a large increase in coronary blood flow without further increasing rate-pressure product.

[Endourologic treatment of the upper urinary tract obstruction in the advanced cancer patients]

88 cancer patients with an upper urinary tract obstruction were endourologically treated. The obstructions were caused by metastasis or invasion of cancer in all patients. First we tried to insert a ureteral stent catheter (STENT). When it failed percutaneous nephrostomy (PCN) was performed. Initially 69 and 19 patients were treated by STENT and PCN, respectively. Of 69 patients with STENT, 13 received PCN later. The average survival of all patients after treatment was 5.7 months. About 60% of the patients were discharged from hospital. The patients treated by STENT and PCN survived for 5.4 months and 6.7 months in average. The STENT was changed 1.8 times on the average in all patients. 79% of the patients who had been treated by STENT experienced only one or two times of STENT changes before dying. Patency period of inserted STENT was studied. On the average the STENT occluded after 72.4 days. The patent period of STENT was longer in the patients group of prophylactic STENT insertion for hydronephrosis. The period was shorter in the patients who showed gross hematuria at the time of surgery. Patent period of STENT was not related to STENT size. Although survival was not so long, over 60% of the patients were able to return to their homes. Endourologic treatment of urinary obstruction was performed in only 6 patients in 1985. The number of such cases has been increasing gradually and currently 20 patients are treated annually. It is supposed that there are many more cancer patients with urinary tract obstruction in their end-stage.(ABSTRACT TRUNCATED AT 250 WORDS)

MR imaging of thymolipoma

A case of thymolipoma that continued from the level of the thymus gland, drooping inferiorly toward the diaphragm is described. Coronal T1-weighted MR images clearly demonstrated the location and characteristic appearances of the tumor.

[Acute mixed lineage leukemia showing resistance to AML and ALL therapy]

A 51-year-old female was who admitted complaining of cough and slight fever and lower limb petechia. The laboratory examinations revealed leukocytosis (49,400/microliters) with blasts (71%) in the peripheral blood. The NCC was 30 x 10(4)/microliters with 84.8% blasts in the bone marrow. Myeloperoxidase staining was positive for 6% of blasts. Auer rods were not seen in some blasts. Thus, acute myeloblastic leukemia (M1) was diagnosed according to FAB classification. In the peripheral blood, 43.3% of blasts expressed CD19, 10.3% of blasts expressed CD20 and 55.6% of blasts expressed CD33 on admission. Though she received two courses of DCMP according to the DCMP-85 protocol, and one combined course of mitoxantrone, etoposide, and Ara-C. The NCC was 20.0 x 10(4)/microliters with 70% blasts in the bone marrow. CD19 was expressed by 72.4% of blasts and 35.0% expressed CD20. The ALL-90 protocol was started, but remission was not achieved. Thus this case was considered to be acute mixed lineage leukemia.

Staphylococcus aureus Wood 46 strain activates human B cells without affecting DNA synthesis or tyrosine phosphorylation

Induction of Ig secretion in human tonsilar B cell by protein A-deficient Staphylococcus aureus WOOD 46 strain (SAW) was examined. SAW induced as much Ig secretion as protein A-rich S. aureus Cowan I strain (SAC) when IL-2 was present in the culture. Activated and resting B cells are separated by Percoll gradient to determine whether SAW stimulates either resting or activated B cells. In resting B cells, SAW plus IL-2 induced IgM secretion significantly, but neither IL-2 nor SAW alone induced IgM secretion. In activated B cells, however, IL-2 induced IgM secretion by itself and SAW plus IL-2 did not induce additional IgM secretion. These results suggest that SAW activates small resting B cells rather than preactivated B cells. Subsequently, mechanisms of B cell activation by SAW and SAC were compared. SAW did not induce [3H]-TdR incorporation through day 1 to 5, and the number of viable cells was not increased by SAW stimulation. Moreover, SAW did not induce significant tyrosine phosphorylation at any concentration tested, when tyrosine phosphorylation of B cells was examined. However, SAC induced both [3H]-TdR incorporation and tyrosine phosphorylation of B cell efficiently. In further experiments, induction of IL-2R and IgM mRNA expressions were examined. SAW by itself induced IL-2R and IgM mRNA expressions without affecting expression of membrane-type IgM mRNA. These results show that SAW activates human B cells in quite a different manner from SAC by up-regulating the expression of secretory type IgM mRNA without affecting cell proliferation nor tyrosine phosphorylation, proposing a distinct B cell activation model from SAC.

Staphylococcus aureus Wood 46 strain activates human B cells without affecting DNA synthesis or tyrosine phosphorylation

Induction of Ig secretion in human tonsilar B cell by protein A-deficient Staphylococcus aureus WOOD 46 strain (SAW) was examined. SAW induced as much Ig secretion as protein A-rich S. aureus Cowan I strain (SAC) when IL-2 was present in the culture. Activated and resting B cells are separated by Percoll gradient to determine whether SAW stimulates either resting or activated B cells. In resting B cells, SAW plus IL-2 induced IgM secretion significantly, but neither IL-2 nor SAW alone induced IgM secretion. In activated B cells, however, IL-2 induced IgM secretion by itself and SAW plus IL-2 did not induce additional IgM secretion. These results suggest that SAW activates small resting B cells rather than preactivated B cells. Subsequently, mechanisms of B cell activation by SAW and SAC were compared. SAW did not induce [3H]-TdR incorporation through day 1 to 5, and the number of viable cells was not increased by SAW stimulation. Moreover, SAW did not induce significant tyrosine phosphorylation at any concentration tested, when tyrosine phosphorylation of B cells was examined. However, SAC induced both [3H]-TdR incorporation and tyrosine phosphorylation of B cell efficiently. In further experiments, induction of IL-2R and IgM mRNA expressions were examined. SAW by itself induced IL-2R and IgM mRNA expressions without affecting expression of membrane-type IgM mRNA. These results show that SAW activates human B cells in quite a different manner from SAC by up-regulating the expression of secretory type IgM mRNA without affecting cell proliferation nor tyrosine phosphorylation, proposing a distinct B cell activation model from SAC.

Purine 8-substitution modulates the ribonuclease L binding and activation abilities of 2',5'-oligoadenylates

Analogues of the 2',5'-linked adenylate trimers monophosphate (p5'A2'p5'A2'p5'A) containing 8-hydroxypropyladenosine, 8-bromoadenosine, and 8-hydroxyadenosine in the first, second, and third nucleotide positions were tested for their ability to bind to and activate RNase L of mouse L cells. p5'AHPr2'p5'AHPr2'p5'AHPr (pAHPr3) (1b) and p5'ABr2'p5'ABr2'p5'ABr (pABr3) (1d) were markedly decreased in ability to bind to the 2-5A dependent endonuclease. On the other hand, analogue of the 2',5'-linked adenylate trimer monophosphate substituted by 8-hydroxyadenosine in the first, second, and third nucleotide position was bound about as well as parent 2-5A [pppA(2'p5'A)2] (p3A3) (1e) to RNase L. Additionally, p5'AOH2'p5'AOH2'p5'AOH (pAOH3) (1c) was as active as parent 2-5A in the rRNA cleavage assay, while pAHPr3 (1b) and pABr3 (1d) were devoid of activity. The 8-substituted analogues of 2-5A were more resistant to the degradation by the (2',5') phosphodiesterase. Finally of particular interest was monophosphate, pAOH3 (1c) which possessed nearly 100% of the translation inhibitory activity of 2-5A triphosphate itself. These results suggest that changes in the base-sugar torsion angles of 2-5A may modulate both binding to and activation of mouse L cell RNase L.

Chemical synthesis and biological activities of analogues of 2',5'-oligoadenylates containing 8-substituted adenosine derivatives

The synthesis of sequence-specific 2'-5'-oligonucleotides and analogues of 2'-5' linked oligoadenylates containing 8-substituted adenosine derivatives [8-hydroxypropyladenosine (AHPr) and 8-hydroxyadenosine (AOH)] is reported. The reaction of 5'-phosphoroimidazolidate of 8-substituted adenosines under conditions of lead ion catalyst did not give the corresponding 2'-5' oligoadenylates containing pAHPr and pAOH. When these reactions were carried out in the presence of uranyl ion (UO2(2+] in place of lead ion as a catalyst, the desired 2'-5' oligoadenylates were obtained. The p5'AHPr2'p5'AHPr2'p5'AHPr and p5'AOH2'p5'AOH2'p5'AOH, p5'A2'p5'A2'pAOH were slightly resistant to snake venom phosphodiesterase. The both circular dichroism and 1H-NMR spectra studies were used to characterize the modified 2'-5' oligoadenylates. Further, the biological activity evaluations of 8-substituted analogues of 2-5A are also described.

An estimation of a model explaining the mechanism causing neurotic disorders using a theory of fuzzy sets

Constructing and estimating a model to explain the mechanism of neurotic disorders is important and significant. The model helps the rearrangement or representation of knowledge obtained from professional physicians. However, it is a very difficult problem, because the objects requiring analysis are mental activities of human beings, and they originally include a comparatively large variance between individuals. The object data were obtained from patients with neurotic disorders who were diagnosed by several doctors for 10 years in a subagricultural areas in Japan. We analyzed the data and calculated the weights attached for personal information depending upon the similarity between the information and the kinds of neurotic disorders using the theory of fuzzy sets. From the results of our analysis, we constructed and estimated a model explaining the mechanism causing neurotic disorders as several linear equations. From data processing points of view, the estimation we attempted is placed in a kind of effective data compression with respect to discrete statistical data.

[Lumbosacral lipoma: computed tomographic scan findings and surgical correction]

Display of the specific anatomic derangements by high-resolution computed tomographic (= CT) scan provides an important basis for planning corrective surgery of lumbosacral lipoma. In this paper, analysis of four infants and a child with lumbosacral lipoma revealed following discrepancy between the image by CT scan and operative finding. Most of lipoma showed a sharply outlined area of low density (approximately -100 H.U.) in the CT scan. Lipoma in the spinal cord parenchym represented intermingled fatty and neural tissue. There were also relatively high density areas in some cases and correspondingly, there were very fibrous lipomas, which could be identified by microscopic histological examination. Although there was a general correlation between the site of lumbosacral skin abnormality and underlying intraspinal lesion, some case does not match perfectly. In conclusion, a removal of the lumbosacral lipoma for the tethering effect always preferable to a total extirpation even though with technological advances in operative magnification and surgical instrumentation and a removal of the compressing lamina is necessary for adequate decompression.

Lucifer yellow, neuronal marking and paraffin sectioning

An unusual procedure with the dye lucifer yellow has provided stable neuronal marking that survives paraffin embedding and sectioning. Lucifer yellow CH was dissolved in an electrolyte containing formaldehyde and injected into the large interneurons of a cricket. Intense fluorescence in the axoplasm was retained even after conventional histological procedures.