CA3 Circuit Model Compressing Sequential Information in Theta Oscillation and Replay

The hippocampus plays a critical role in the compression and retrieval of sequential information. During wakefulness, it achieves this through theta phase precession and theta sequences. Subsequently, during periods of sleep or rest, the compressed information reactivates through sharp-wave ripple events, manifesting as memory replay. However, how these sequential neuronal activities are generated and how they store information about the external environment remain unknown. We developed a hippocampal cornu ammonis 3 (CA3) computational model based on anatomical and electrophysiological evidence from the biological CA3 circuit to address these questions. The model comprises theta rhythm inhibition, place input, and CA3-CA3 plastic recurrent connection. The model can compress the sequence of the external inputs, reproduce theta phase precession and replay, learn additional sequences, and reorganize previously learned sequences. A gradual increase in synaptic inputs, controlled by interactions between theta-paced inhibition and place inputs, explained the mechanism of sequence acquisition. This model highlights the crucial role of plasticity in the CA3 recurrent connection and theta oscillational dynamics and hypothesizes how the CA3 circuit acquires, compresses, and replays sequential information.

Distributed sensory coding by cerebellar complex spikes in units of cortical segments

Sensory processing is essential for motor control. Climbing fibers from the inferior olive transmit sensory signals to Purkinje cells, but how the signals are represented in the cerebellar cortex remains elusive. To examine the olivocerebellar organization of the mouse brain, we perform quantitative Ca²⁺ imaging to measure complex spikes (CSs) evoked by climbing fiber inputs over the entire dorsal surface of the cerebellum simultaneously. The surface is divided into approximately 200 segments, each composed of ∼100 Purkinje cells that fire CSs synchronously. Our in vivo imaging reveals that, although stimulation of four limb muscles individually elicits similar global CS responses across nearly all segments, the timing and location of a stimulus are derived by Bayesian inference from coordinated activation and inactivation of multiple segments on a single trial basis. We propose that the cerebellum performs segment-based, distributed-population coding that represents the conditional probability of sensory events.

Task-Related Synaptic Changes Localized to Small Neuronal Population in Recurrent Neural Network Cortical Models

Humans have flexible control over cognitive functions depending on the context. Several studies suggest that the prefrontal cortex (PFC) controls this cognitive flexibility, but the detailed underlying mechanisms remain unclear. Recent developments in machine learning techniques allow simple PFC models written as a recurrent neural network to perform various behavioral tasks like humans and animals. Computational modeling allows the estimation of neuronal parameters that are crucial for performing the tasks, which cannot be observed by biologic experiments. To identify salient neural-network features for flexible cognition tasks, we compared four PFC models using a context-dependent integration task. After training the neural networks with the task, we observed highly plastic synapses localized to a small neuronal population in all models. In three of the models, the neuronal units containing these highly plastic synapses contributed most to the performance. No common tendencies were observed in the distribution of synaptic strengths among the four models. These results suggest that task-dependent plastic synaptic changes are more important for accomplishing flexible cognitive tasks than the structures of the constructed synaptic networks.

Selective growth inhibition by suppression of F1Fo ATPase in canine malignant melanoma cell lines

Canine malignant melanoma (CMM) is a highly aggressive and fatal neoplasm. To identify potential therapeutic compounds and/or targets, 320 compounds were screened for their growth inhibitory activity in a CMM line (CMM-1) using a chemical library known to target specific signaling pathways/cell growth-related molecules. Among the compounds screened, the F1Fo ATPase inhibitor oligomycin showed potent growth inhibitory effects in CMM-1 cells, while exhibiting less toxic effects in a non-neoplastic control cell line (MDCK cells). The growth inhibitory effect of oligomycin A was then examined using six CMM lines and MDCK cells. Three CMM lines were highly sensitive to oligomycin A, with around 3000-20 000 times lower IC₅₀ compared with oligomycin A-resistant CMM lines and MDCK cells. Oligomycin A-sensitive CMM-1 cells exhibited much greater oligomycin A-induced decreases in cellular ATP compared to oligomycin A-resistant cell lines. Although the oligomycins are clinically unsuitable because of its in vivo toxicity, these findings implicate the potential of F1Fo ATPase as a therapeutic target in a subset of CMM.

Abstract P4-09-15: BRCAness and PD-L1 expression of basal-like and not basal-like triple negative breast cancer

Background: Triple Negative Breast Cancer (TNBC) subtype occurs in approximately 20% of all patients with breast cancer and is associated with rapid growth, early metastasis and poor prognosis compared with other subtypes. TNBCs are a heterogeneous disease entity and further subclassification is needed, but still ongoing. In this study, we assessed BRCAness, defined as shared characteristics between sporadic and BRCA1-mutated tumors, in a cohort of basal-like and non-basal-like TNBCs.

Patients and Methods: DNA was isolated from formalin-fixed paraffin-embedded tumor tissues and BRCAness status was analyzed in 262 patients with primary TNBCs resected at our three hospitals between 2004 and 2014. Classification of BRCAness was performed by using Multiple Ligation-dependent Probe Amplification (MLPA) with the probemix P376 BRCA1ness by MRC (Amsterdam, Holland). The tumor subtypes were routinely determined immunohistochemically by using resected specimens. Basal-like phenotype was defined as being positive for Epidermal Growth Factor Receptor (EGFR) and/or Cytokeratin 5/6 (CK5/6). Moreover, TNBCs were stained and analyzed for programmed cell death ligand-1 (PD-L1) expression as a target of new immune therapies.

Results: Of 262 TNBCs, 232 tumors (88.5%) was a basal-like phenotype. The results of MLPA assay showed that 159 (68.5%) of 232 tumors had a BRCAness profile. Patients with basal-like BRCAness tumors were younger than patients with basal-like non-BRCAness tumors (p<0.0001). There was no significant difference between the two groups regarding pathological stage. The basal-like BRCAness group had shorter relapse-free survival (RFS) and overall survival (OS) than the basal-like non-BRCAness group (p=0.028 and p=0.13, respectively), and anthracycline-based regimens provided greater benefit to the basal-like BRCAness group significantly (p=0.01 in RFS and p=0.007 in OS). PD-L1 was expressed in 71 (44.7%) of 159 basal-like TNBCs with BRCAness.

Conclusion: We reported the majority of basal-like TNBCs showed a BRCAness profile and PD-L1 expressed in approximately 50% of BRCAness tumors. It is known that about 30% of BRCAness tumors are BRCA1-mutated tumors. Those biomarkers are essential for subclassification of TNBCs and may offer not only platinum-based chemotherapy but also novel therapies, such as immune-targeted therapies of PD-1/PD-L1 inhibitors and PARP inhibitors, to patients with basal-like TNBCs with BRCAness.

Citation Format: Mori H, Kubo M, Yamada M, Kai M, Osako T, Nishimura R, Arima N, Okido M, Kuroki S, Oda Y, Nakamura M. BRCAness and PD-L1 expression of basal-like and not basal-like triple negative breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-09-15.

Oxygen reduction activity of carbon nitride supported on carbon nanotubes

Fuel cells offer an alternative to burning fossil fuels, but use platinum as a catalyst which is expensive and scarce. Cheap, alternative catalysts could enable fuel cells to become serious contenders in the green energy sector. One promising class of catalyst for electrochemical oxygen reduction is iron-containing, nanostructured, nitrogen-doped carbon. The catalytic activity of such N-doped carbons has improved vastly over the years bringing industrial applications ever closer. Stoichiometric carbon nitride powder has only been observed in recent years. It has nitrogen content up to 57% and as such is an extremely interesting material to work with. The electrochemical activity of carbon nitride has already been explored, confirming that iron is not a necessary ingredient for 4-electron oxygen reduction. Here, we synthesize carbon nitride on a carbon nanotube support and subject it to high temperature treatment in an effort to increase the surface area and conductivity. The results lend insight into the mechanism of oxygen reduction and show the potential for carbon nanotube-supported carbon nitride to be used as a catalyst to replace platinum in fuel cells.

Lack of association between the insertion/deletion polymorphism of the angiotensin-converting enzyme gene and vasospastic angina

BACKGROUND AND HYPOTHESIS

It has been suggested that the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene is an independent risk factor for coronary atherosclerosis and myocardial infarction, but its relation to vasospastic angina has not been fully proven. In the present study, we investigated the possible relationship between the ACE I/D genotype and vasospastic angina.

METHODS

We explored the distribution of the ACE genotype in 20 patients with vasospastic angina without fixed coronary artery stenosis, 55 angina patients with fixed coronary artery stenosis, and 30 control subjects without coronary artery disease.

RESULTS

The frequency of the DD genotype in patients with vasospastic angina (DD: 30.0%, ID: 20.0%, II: 50.0%) did not differ from that in the control subjects (DD: 23.3%, ID: 26.7%, II: 50.0%), while the frequency in patients with coronary artery stenosis (DD: 43.7%, ID: 21.8%, II: 34.5%) was significantly higher than that in the control subjects. The frequency of the D allele also did not differ between patients with vasospastic angina (0.40) and control subjects (0.37), while the frequency was significantly higher in patients with coronary artery stenosis (0.55).

CONCLUSIONS

These findings suggest that the ACE DD genotype is a potent genetic risk factor for organic coronary artery disease, while it confers no appreciable increase in risk of vasospastic angina. These results also suggest the diversity of the pathogenesis of vascular lesions in these two types of coronary artery disease.

Right ventricular dysplasia with complete atrioventricular block: necessity and limitation of left ventricular epicardial pacing

This paper reports a case of right ventricular dysplasia, in which the patient presented with atrioventricular block and was followed for more than 8 years under left ventricular epicardial pacing. Five years after first epicardial pacemaker implantation, loss of capture occurred. Replacement of the epicardial leads was performed.

Persistent hyperparathyroidism in renal allograft recipients: vitamin D receptor, calcium-sensing receptor, and apoptosis

The phenotypic changes in parathyroid cells after successful renal transplantation remain to be elucidated. We compared 10 diffuse and 11 nodular hyperplastic parathyroid glands from five renal allograft recipients with persistent hyperparathyroidism, with five diffuse and 13 nodular hyperplasia from seven uremic patients on hemodialysis, and 13 normal glands. Comparisons included expressions of both vitamin D receptor (VDR) and calcium-sensing receptor (CaSR), proliferative activity (Ki67), and apoptosis (TUNEL). Immunoreactivity was assessed semiquantitatively and expressed as labeling index. The area/cell was also measured to assess cellular hypertrophy. The labeling indexes of VDR (587+/-71; mean+/-s.e.m.) and CaSR (45.0+/-2.8) in recipients' diffuse hyperplasia were significantly higher than those in uremic diffuse hyperplasia (224+/-44, 29.3+/-2.3, respectively) (P<0.01, each). However, these expressions remained low in recipients' nodular hyperplasia (42+/-8, 11.8+/-1.4, respectively). Ki67 labeling index in recipients' nodular hyperplasia (7+/-1) was significantly smaller than in uremic patients (24+/-6, P<0.01). TUNEL labeling index in recipients' diffuse hyperplasia (30+/-5) was the highest among the groups. The cell volume tended to be smaller in both patterns of hyperplasia in allograft recipients compared with uremic patients. Our results suggest that the phenotypic change in parathyroid cells after renal transplantation depends on the pattern of hyperplasia, where it is normalized only in diffuse hyperplastic glands in which the number of cells also regresses with significant induction of apoptosis.

Infrasternal mediastinoscopic surgery for anterior mediastinal masses

BACKGROUND

Infrasternal mediastinoscopic surgery is a new alternative to the thoracoscopic approach for patients with anterior mediastinal masses.

METHODS

We applied this technique to 18 thymectomies, one thymomectomy, and one cystectomy in a total of 20 patients with anterior mediastinal masses and then assessed the surgical results.

RESULTS

Infrasternal mediastinoscopic surgery was accomplished in 18 of the 20 patients (90%). The pathological diagnoses included 13 Masaoka stage I thymomas, one stage II thymoma, two stage III thymomas, one thymic cyst, one pericardial cyst, one thymic granuloma, and one mature teratoma. Two patients with stage III thymoma required conversion to sternotomy, one for invasion into the innominate vein and the other for invasion into the pericardium. There was no surgically related mortality or complications in any patients.

CONCLUSION

Infrasternal mediastinoscopic surgery is safe and feasible for stage I thymoma and other benign tumors in the anterior mediastinum.

Serum 7alpha-hydroxycholesterol levels during liver regeneration after hepatectomy in humans

BACKGROUND/AIMS

Changes in bile acid synthesis during liver regeneration after hepatectomy is little known in humans. Since it has been reported that the serum 7 alpha-hydroxycholesterol levels reflect the hepatic bile acid synthesis and that the determination of bile acid synthesis is useful to assess the liver regeneration rate, we determined the serum 7 alpha-hydroxycholesterol level during liver regeneration after hepatectomy in clinical patients.

METHODOLOGY

The serum 7 alpha-hydroxycholesterol levels were determined by gas-liquid chromatography-mass spectrometry-selected ion monitoring method before and on days 1, 3, 5, 7, 14 and 21 after hepatectomy in twenty consecutive patients.

RESULTS

The 7 alpha-hydroxycholesterol levels became lower between days 1 and 7, were increased on day 14, and then decreased on day 21 after hepatectomy. The patients with preoperative external biliary drainage showed a higher serum 7 alpha-hydroxycholesterol level than those without biliary drainage before hepatectomy. The former showed lower serum 7 alpha-hydroxycholesterol levels than the latter throughout the 21 days after hepatectomy. In patients whose liver resection rate was more than 50%, the serum 7 alpha-hydroxycholesterol levels were kept lower until 21 days after hepatectomy compared with those whose liver was excised less than 50%.

CONCLUSIONS

It is concluded that the patients who had preoperative biliary drainage or major hepatic resection seem to have less hepatic reserve capacity for bile acid synthesis after hepatectomy.

Thoracic cage extent of melorheostosis depicted by multislice CT

The ribs and vertebrae are rarely affected by melorheostosis. We present a case of melorheostosis of the ribs and thoracic vertebrae, in which multislice computed tomography (CT) was useful in depicting its extent and defining its sclerotome distribution.

Differences in biliary lipid excretion after major hepatectomy in obstructive jaundiced rats with preoperative internal, external, or no biliary drainage

Necessity of preoperative biliary drainage for patients with obstructive jaundice is still controversial. We recently reported that liver regeneration after major hepatectomy was better restored in a rat model of obstructive jaundice with preoperative internal biliary drainage than that without biliary drainage or with external biliary drainage. The aim of this study was to investigate the differences in biliary lipid excretion after hepatectomy in obstructive jaundiced rats with or without preoperative internal or external biliary drainage. After bile duct ligation for 7 days, rats were randomly divided into the three groups; obstructive jaundice-hepatectomy (OJ-Hx), internal biliary drainage-hepatectomy (ID-Hx), and external biliary drainage-hepatectomy (ED-Hx) groups. 70% hepatectomy and internal biliary drainage were carried out 7 days after biliary decompression in the latter two groups and without biliary decompression in the OJ-Hx group. On the day of and on days 1, 2, 3 and 7 after hepatectomy, the liver weight, DNA synthesis rate, biliary lipids excretion rates, and bile acid composition were determined. In the ID-Hx group, the DNA synthesis rate and relative liver weight were significantly higher than those of the OJ-Hx and ED-Hx groups. The excretion rates of biliary lipids were disturbed in the ED-Hx group compared with those in the ID-Hx group and the values in the OJ-Hx group were in-between the ID-Hx and ED-Hx group. The liver regeneration rate was significantly correlated with bile flow and excretion rates of biliary lipids. The maintenance of enterohepatic circulation of biliary lipids before hepatectomy may be important for the liver regeneration.

Endoscopic ultrasonography in patients with thyroid cancer: its usefulness and limitations for evaluating esophagopharyngeal invasion

BACKGROUND AND STUDY AIMS

Although computed tomography (CT) and magnetic resonance imaging (MRI) are useful for detecting esophagopharyngeal invasion by thyroid cancer, they cannot assess the depth of invasion, which is important for the surgical planning. In the present study, endoscopic ultrasonography (EUS) of the esophagus was used to assess esophagopharyngeal invasion by thyroid cancer, and the value of this technique was assessed prospectively.

PATIENTS AND METHODS

Between 1 December 1998 and 31 December 2000, EUS examinations were carried out in 59 patients in whom esophagopharyngeal invasion by thyroid cancer was suspected due to large tumors or tumors with poor mobility. The EUS findings were evaluated in 52 patients (10 men, 42 women; mean age 62.4 years; mean tumor size 39.5mm) with complete resections, and compared with the pathological results.

RESULTS

The diagnostic specificity and accuracy of EUS in assessing invasion into the muscularis propria (82.9 %, 82.7 %) were greater than those of MRI (60 %; P = 0.034, 65.4 %; P = 0.044) and esophagography (58.8 %; P = 0.034, 60 %; P = 0.028). The accuracy for detecting cancer invasion located in the upper part of the lobe was less than for invasion in the middle and/or lower parts of the lobe ( P = 0.020). Conclusions. EUS is useful for assessing esophagopharyngeal invasion by thyroid cancer, although its effectiveness may be limited in thyroid lesions located in the upper part of the lobe.

Low-dose ACTH therapy for West syndrome: initial effects and long-term outcome

BACKGROUND

Most Japanese pediatric neurologists attempt other treatments before using adrenocorticotropic hormone (ACTH) therapy for West syndrome (WS), and even then, they use only a low-dose synthetic ACTH to avoid serious adverse effects. In this multi-institutional study, the authors analyzed the initial effects, adverse effects, and long-term outcome in patients treated with low-dose synthetic ACTH in Japan.

METHODS

The medical records of 138 patients with WS, who were treated with low-dose synthetic ACTH therapy for the first time at the authors' institutions between 1989 and 1998, were analyzed.

RESULTS

At the end of ACTH therapy, excellent effect on seizures was noted in 106 of 138 (76%) patients, good effect in 23 (17%), and poor effect in 9 (7%). Initial effects on EEG were excellent in 53 of 138 (38%) patients, good in 76 (55%), and poor in 9 (7%). As for seizure prognosis at the time of follow-up, 51 of 99 (52%) patients were seizure-free, whereas 48 (48%) patients had seizures. Mental outcome was normal in 6 of 98 (6%) patients, mild mental retardation in 16 (16%), moderate mental retardation in 26 (27%), and severe mental retardation in 50 (51%). The initial effects of ACTH on seizures and long-term outcome were not dose dependent (daily dosage 0.005 to 0.032 mg/kg, 0.2 to 1.28 IU/kg; total dosage 0.1 to 0.87 mg/kg, 4 to 34.8 IU/kg). The severity of adverse effects correlated with total dosage of ACTH, and the severity of brain volume loss due to ACTH correlated well with the daily dosage and total dosage of ACTH.

CONCLUSION

Low-dose synthetic ACTH therapy is as effective for the treatment of WS as the higher doses used in previous studies. The dosage of synthetic ACTH used in the treatment of WS can be decreased as much as possible to avoid serious adverse effects.

Infrasternal mediastinoscopic thymectomy in myasthenia gravis: surgical results in 23 patients

BACKGROUND

Infrasternal mediastinoscopic surgery is a new approach to resection of the anterior mediastinal mass.

METHODS

We evaluated this new approach in 23 patients with myasthenia gravis who underwent total thymectomy assisted by infrasternal mediastinoscopy between 1998 and 2000. The results were analyzed with special reference to morbidity and short-term improvement of the disease severity determined according to quantitative myasthenia gravis (QMG) scores.

RESULTS

Complete removal of the thymic gland with the pericardial adipose tissue was accomplished through an infrasternal mediastinoscopic approach in 21 of the 23 (91.3%) patients. The remaining 2 patients required conversion to sternotomy, the one for insufficient sternal lifting with vascular tape and the other for invasion of a thymoma to the innominate vein. There was no related mortality and only one complication, a phrenic nerve injury in 1 patient (4.3%). Significant clinical improvement of disease was achieved in the short term and several advantages were apparent.

CONCLUSIONS

Infrasternal mediastinoscopic thymectomy is safe and feasible for patients with myasthenia gravis.

Cancer chemopreventive activity of phenylpropanoid esters of sucrose, vanicoside B and lapathoside A, from Polygonum lapathifolium

To search for cancer chemopreventive agents from natural resources, many phytochemicals have been screened using the in vitro synergistic assay indicated by the inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) by 12-O-tetradecanoylphorbol-13-acetate (TPA). Two phenylpropanoid esters of sucrose, vanicoside B and lapathoside A, were isolated from the aerial part of Polygonum lapathifolium as inhibitors on the EBV-EA induction. These compounds also exhibited significant anti-tumor-promoting effects on mouse two-stage skin carcinogenesis induced by 7,12-dimethylbenz[a]anthracene (DMBA, as an initiator) and TPA as a promoter. Further, vanicoside B exhibited the remarkable inhibitory effect on two-stage carcinogenesis test of mouse skin tumors initiated with an NO donor, NOR-1.

[A pediatric case of acute focal bacterial nephritis; comparison with the reports in Japanese child cases]

We report an 8-year-old boy with acute focal bacterial nephritis (AFBN). At the age of 3 months, he had a history of urinary tract infection and vesicoureteral reflux. He was admitted to our hospital because of high fever and costovertebral angle pain. Although acute pyelonephritis was suspected, neither pyuria nor cultures of blood and urine were positive. An initial ultrasonogram (US) of his kidneys was normal except for bilateral hydronephrosis. Two days later, however, a computed tomography (CT) revealed a poorly enhanced mass in the upper pole of the right kidney. Similar findings were also observed by US. Under the diagnosis of AFBN, he received antibiotics for 3 weeks. Voiding cystourethrogram showed both-sided vesicoureteral reflux and he underwent an operation. At present the mass of the kidney still remains, albeit its size tends to decrease. We suggest that an early examination of US or enhanced CT is necessary in cases with fever of unknown origin, considering the possibility of AFBN even if neither pyuria nor cultures of urine are positive.

[Adjuvant GM-CSF cytokine gene therapy for breast cancer]

The aim of this study was to examine the enhancement of antitumor immunity of irradiated granulocyte macrophage-colony-stimulating factor (GM-CSF) gene-transduced mouse breast cancer cells.

METHODS

BALBMC mouse were vaccinated subcutaneously with saline or irradiated mouse breast cancer cells, BALBMC (1 x 10(6)/mouse), infected or not infected with recombinant adenovirus harboring GM-CSF gene on day-7. Mice were injected with parental cells (1 x 10(5)/mouse) on day 0.

RESULTS

No mice vaccinated with irradiated GM-CSF producing BALBMC cells developed a tumor during the observation period of up to 16 weeks, whereas 100% of mice injected with saline developed a tumor.

CONCLUSION

Our study demonstrates the feasibility of this immunotherapeutic approach as a novel adjuvant cancer therapy after surgery for breast cancer.

New phenylpropanoid esters of sucrose from Polygonum lapathifolium

Four new phenylpropanoid esters of sucrose, lapathosides A (1), B (2), C (3), and D (4), were isolated from the aerial parts of Polygonum lapathifolium together with known esters, vanicoside B (5) and hydropiperoside (6). The structures of 1-4 were determined by spectral (1D and 2D NMR and MS) analysis. Lapathoside A (1) and vanicoside B (2) showed significant inhibitory effects on the Epstein-Barr virus early antigen activation by tumor-promoters.

Video-assisted parathyroidectomy for primary hyperparathyroidism: a new approach involving a skin-lifting method

BACKGROUND

Recent advances have allowed the performance of parathyroidectomy as an endoscopic procedure. Carbon dioxide (CO2) insufflation can be used to create a working space in the anterior neck, but it has been associated with a number of complications. We have devised a skin-lifting method to overcome these problems.

METHODS

Eleven consecutive patients underwent video-assisted parathyroidectomy. Preoperative imaging revealed a solitary adenoma in all 11 cases. A 3-cm oblique incision was made below the clavicle, and a 5-mm incision was made on the lateral neck. After the skin was lifted, video-assisted parathyroidectomy was performed.

RESULTS

Surgery required 186 +/- 50 min. No conversions to conventional cervicotomy were needed. Levels of serum calcium and intact parathormone decreased significantly in all patients on postoperative day 1. Laryngeal recurrent nerve paresis and seroma were noted in one patient each.

CONCLUSIONS

Our procedure eliminates any potential CO2 problems and offers the advantages of direct manipulation and improved cosmesis. Endoscopic parathyroidectomy should be considered a viable option for the surgical treatment of a solitary adenoma.

[Docetaxel was effective as neoadjuvant chemotherapy for patients after failure of trans-arterial neoadjuvant chemotherapy with CEF in 2 cases of advanced breast cancer]

Docetaxel was effective as a second line neoadjuvant chemotherapy after failure of cyclophosphamide, epirubicin and 5-FU (CEF) in 2 cases of breast cancer. In Case 1, 4 cycles of trans-arterial neoadjuvant chemotherapy of docetaxel showed a PR effect after failure of 2 cycles of trans-arterial neoadjuvant chemotherapy with CEF. This patient died of pleuritis carcinomatosa 18 months after surgery for breast cancer (latissimus dorsi muscle myocutaneous flap after radical mastectomy). In Case 2, 6 cycles of neoadjuvant venous drip infusion of docetaxel resulted in a CR effect after failure of 2 cycles of transarterial neoadjuvant chemotherapy with CEF. This patient is alive and disease-free 27 months after the operation for breast cancer (same operation as for Case 1). Docetaxel was effective as neoadjuvant chemotherapy for patients after failure of trans-arterial neoadjuvant chemotherapy with CEF.

Pericaval fat collection mimicking an intracaval lesion on CT in patients with chronic liver disease

BACKGROUND

Localized fat collections, which mimic fat-containing lesions of the inferior vena cava (IVC) on computed tomographic (CT) images, have been reported as rare incidental findings. Our goal was to evaluate the association of this CT finding with chronic liver disease.

METHODS

Sixty-one patients with chronic liver disease were prospectively studied with contrast-enhanced abdominal CT. The prevalence, attenuation, location, shape, and size of the pericaval fat collections were assessed. Multidirectional reformatted CT images were obtained from helical CT data to identify origins of the pericaval fat collections. Sixty-one patients without chronic liver disease were studied as control subjects.

RESULTS

Pericaval fat collections were seen on abdominal CT in 16 (26.2%) of the 61 patients. On the reformatted images, the fat collections were contiguous to the fat tissue around the subdiaphragmatic esophagus in all 16 patients. The fat collections were located at the posterior aspect of the IVC in 12 patients. In the control group, pericaval fat collection mimicking an intracaval lesion was not seen.

CONCLUSION

In patients with chronic liver disease, pericaval fat collections are not rare CT findings and their characteristic location is considered to be posterior to the IVC. It is important not to misinterpret such CT findings as abnormalities of the IVC, such as thrombus or tumors.

Effects of internal biliary bypass on the regulation of hepatic cholesterol 7alpha-hydroxylase activity in rats

In order to re-evaluate the importance of the enterohepatic circulation of bile acid in the regulation of the activities of hepatic cholesterol 7alpha-hydroxylase, bile acid metabolism was examined in internal biliary bypass models of rats. A polyethylene tube was inserted into the common bile duct and another side of the tube was placed in the duodenum (DD), lower jejunum (JD), cecum (CeD), or transverse colon (CoD) as internal biliary bypass models and in the urinary bladder as an external biliary drainage (ED). After bile diversion for 7 days in each group, hepatic cholesterol 7alpha-hydroxylase activities, bile acid concentrations in bile, serum, and portal vein, biliary bile acid compositions, and intestinal absorption rates of infused labeled taurocholic acid were analyzed. Hepatic cholesterol 7alpha-hydroxylase activity was similar in the JD group compared with the DD group, however, it was significantly up-regulated in the CeD (227% of the DD group), CoD (312%), and ED groups (316%). Biliary, serum, and portal bile acid concentrations were not significantly changed in the DD, JD, and CeD groups but those were significantly lower in the CoD and ED groups compared with the DD group. The proportion of the secondary bile acids was significantly increased in the CeD group and was decreased in the CoD and ED groups. The absorption rate of taurocholic acid was almost 100%, 56%, and 23% in the JD, CeD, and the CoD group, respectively. As the cholesterol 7alpha-hydroxylase activity was not significantly changed in the JD group and the predominance of secondary bile acids did not suppress the enzyme activity in the CeD group, the luminal factor, which is absorbed in the presence of bile acids, and the bile acid metabolites are not likely the regulatory factor. The cholesterol 7alpha-hydroxylase activity seems to be primarily regulated by the intestinal absorption of bile acids and partly by the intestinal mucosal factor which is linked to the intestinal bile acid absorption.

Three patients with ophthalmoplegia associated with Campylobacter jejuni

Cranial polyneuropathy is idiopathic in most patients. Idiopathic cranial polyneuropathy is an acute postinfectious syndrome, along with Guillain-Barré syndrome and Miller Fisher syndrome, in which the common preceding pathogen is Campylobacter jejuni. Serum anti-GQ1b antibodies are elevated in Miller Fisher syndrome and Guillain-Barré syndrome with ophthalmoplegia. Three patients with idiopathic cranial polyneuropathy with predominant ocular involvement are presented. C. jejuni isolated from stool specimens belonged to Penner serotypes O:4, O:23, and O:33. Serum anti-GQ1b antibodies were elevated in all patients but demonstrated rapid reduction concomitant with clinical recovery. All patients recovered completely. Because both preceding C. jejuni infection and elevated anti-GQ1b antibodies decreasing with time were seen in all patients, the pathogenesis of idiopathic cranial polyneuropathy with ophthalmoplegia may be similar to that of Miller Fisher syndrome.

[A case of secondary meningoencephalitis associated with Mycoplasma pneumoniae infection]

An 11-year-old girl was admitted to our hospital with complaint of disturbance of consciousness and muscle weakness. We diagnosed her as having meningoencephalitis because of the pleocytosis in the cerebrospinal fluid (CSF) and diffuse slow EEG waves. Laboratory tests in admission showed that serum passive hemagglutinin titer to Mycoplasma pneumoniae (M. pneumoniae) was 1:5,120, serum antibody titer to galactocerebroside (Gc) was 1:160, and CSF interleukin-6 (IL-6) level was 20,500 pg/ml, but a specific DNA to M. pneumoniae was not detected in CSF using the polymerase chain reaction. Cranial and whole spine MRI were unremarkable. These results suggest that anti-Gc antibody and IL-6 play some roles in the development of mycoplasmal central nervous system involvement.

Increased urinary excretion of bilirubin oxidative metabolites in septic patients: a new marker for oxidative stress in vivo

BACKGROUND

Bilirubin oxidative metabolites (BOMs) are generated from bilirubin as a result of its scavenging action against free radicals. During sepsis, excess amounts of free radicals are produced, and they play an important role in the pathophysiological process. We studied whether urinary excretion of BOMs would increase under septic conditions in humans and compared BOM levels with other well-established clinical parameters of inflammation.

METHODS

In 19 septic patients and 28 nonseptic control patients, the BOM concentrations in urine were measured by enzyme-linked immunosorbent assay with an anti-bilirubin antibody.

RESULTS

Urinary BOM levels in septic patients were much higher than those in control patients (21.6 +/- 2.5 vs 1.4 +/- 0.4 micromol/g creatinine, P < 0.001). Although there was a linear correlation between urinary BOM and serum total bilirubin levels (r = 0.392, P = 0.008), serum bilirubin levels were not significantly higher in the septic group than in the control group (P = 0.072). BOM levels correlated with body temperature (r = 0.801, P < 0.001), white blood cell counts in the peripheral blood (r = 0.590, P < 0.001), serum C-reactive protein (r = 0.653, P < 0.001), and the acute physiological and chronic health evaluation (APACHE II) score (r = 0.467, P = 0.003).

CONCLUSIONS

These results demonstrated a urinary increase in BOMs in septic patients. This increase indicates that urinary BOM level is a possible marker for continuous monitoring of sepsis severity in clinical practice.

[Colonic varices; a case report]

Colonic varices is a rare entity that is caused by portal hypertension in most instances. In the case reported here, barium enema and colonoscopy showed multiple tortuous polypoid lesions with intact mucosal surface. Inferior mesenteric angiography showed arteriovenous malformation in the sigmoid colon, complete obstruction of the inferior mesenteric vein, and tortuous dilated marginal veins. We assume that the colonic varices of this case was secondary to complete obstruction of the inferior mesenteric vein following AVM of the sigmoid colon. Close follow-up should is warranted in cases of colonic varices because of the risk of bleeding.

Video-assisted parathyroidectomy by a skin-lifting method for primary hyperparathyroidism

OBJECTIVE

The use of endoscopic surgical procedures has rapidly spread to abdominal and thoracic surgeries and subsequently to surgeries of the neck region. Several surgeons initiated endoscopic parathyroidectomy using CO2 insufflation to create the working space; however, they reported various complications. We describe here a skin-lifting method that may have few complications.

METHODS

A 65-year-old man was diagnosed with primary hyperparathyroidism due to a solitary adenoma of the left inferior parathyroid gland. A 3-cm oblique incision was made below the left clavicle, and a 5-mm incision was made on the lateral neck. After the skin was lifted up, we performed video-assisted parathyroidectomy.

RESULTS

Parathyroid extirpation took 2 hours and blood loss was minimal. The patient had minimal pain and no complications postoperatively. Serum concentrations of calcium and intact parathyroid hormone were normalized on the next day.

CONCLUSION

Using the skin-lifting method, we obtained a sufficient operative view and encountered no complications. This procedure is cosmetically desirable, and we consider it a feasible alternative for the treatment of parathyroid adenoma.

Calpastatin domain L is involved in the regulation of L-type Ca2+ channels in guinea pig cardiac myocytes

We have found previously that L-type Ca2+ channel run-down in cell-free patches is partially (10-28%) reversed by calpastatin (CS) and have suggested that CS, an endogenous inhibitor of calpain, has a Ca2+-channel-regulating function. CS is composed of repetitive domains 1-4 (calpain-inhibitory domain) and domain L (a domain whose function is unknown). We therefore investigated which domain of CS was involved in the regulation of Ca2+ channel activity in guinea pig cardiac myocytes using the patch-clamp technique. After the patches were excised into inside-out mode in basic internal solution, the Ca2+ channel activity ran down to 0.45% of the control level recorded in the cell-attached mode. Application of human recombinant full-length CS (25 microM) and domain L (25 microM) restored the Ca2+ channel activity to 13 and 19% of the control level, respectively, while the channel activity was not restored by CS domain 1 (25 microM) (0.66%). Mouse CS domain XLL (25 microM), a complex of domain XL and domain L, restored the calcium channel activity to 11% of the control level. These results suggested that the Ca2+ channel-regulating function of CS is located in domain L. This study is the first description of the function of CS domain L.

Administration of bacterial lipopolysaccharide to rats induces heme oxygenase-1 and formation of antioxidant bilirubin in the intestinal mucosa

Heme oxygenase (HO)-1, the rate-limiting enzyme in heme degradation, is induced by oxidative stress and its major end product, bilirubin, is a potent physiological antioxidant. We studied the induction of HO-1 and bilirubin production in intestinal mucosa using a rat model of sepsis. E. coli lipopolysaccharide was administered intraperitonealy to male Wistar rats and intestinal mucosa was harvested. Intestinal lipid peroxides increased significantly at 1 hr and peaked at 170% of the control value at 5 hr. GSH significantly decreased at 3 hr, reaching the nadir of 50% of the control value at 5 hr. HO-1 mRNA was maximally induced fivefold at 3 hr and HO-1 protein maximally increased to 10 times the control value at 7.5 hr. Both bilirubin and bilirubin oxidative metabolites were maximally increased at 10 hr, to 4.3 and 3.7 times the control value, respectively. These data suggest that oxidative stress in sepsis quickly induces HO-1 in intestinal mucosa and that subsequent production of bilirubin works as an antioxidant. The small intestinal mucosa is an active participant in the general response to sepsis.

A study of conformational stability of polyglycine and poly(L-alanine), and polyglycine/poly(L-alanine) blends in the solid state by (13)C cross-polarization/magic angle spinning NMR

13C Cross-Polarization/Magic Angle Spinning nmr and T(1rhoH) experiments of polyglycine (PG), poly(L-alanine) (PLA), and PG/PLA blends prepared from dichloroacetic acid solution have been carried out, in order to elucidate the conformational stability of these polypeptides in the solid state. From these experimental results, it was clarified that the conformations of PG and PLA in their blends are strongly influenced by intermolecular hydrogen-bonding interactions that cause their miscibility at the molecular level.

Gadolinium pretreatment decreases survival and impairs liver regeneration after partial hepatectomy under ischemia/reperfusion in rats

BACKGROUND

Modulation of Kupffer cell functions by treatment with gadolinium chloride protects the liver against reperfusion injury. However, its effect on liver regeneration after hepatectomy under ischemia/reperfusion has not been studied. Using a common clinical ischemia/reperfusion technique, we examined the effect of gadolinium on liver regeneration after hepatectomy in rats.

METHODS

After an initial 15-minute ischemia and 15-minute reperfusion, 70% hepatectomy was performed during the second 15-minute ischemia period in gadolinium-pretreated (gadolinium group) and saline solution--pretreated (control group) rats. The 24-hour survival rate, relative liver weight, DNA synthesis rate, and hepatic adenosine triphosphate level were examined immediately after hepatectomy and on postoperative days (PODs) 1, 2, 3, and 7. Serum levels of total bilirubin, glutamic pyruvic transaminase, and endotoxin were also measured.

RESULTS

The 24-hour survival rate was significantly lower in the gadolinium group (67%) than in the control group (100%). On POD 1, the relative liver weight and DNA synthesis rate were significantly lower in the gadolinium group than in the control group. On POD 1, serum total bilirubin and endotoxin levels were significantly higher in the gadolinium group than in the control group. Immediately after hepatectomy, the hepatic adenosine triphosphate level was significantly lower in the gadolinium group than in the control group.

CONCLUSIONS

Under ischemia/reperfusion, gadolinium pretreatment impairs liver regeneration and energy status after hepatectomy and decreases postoperative survival.

[A case of synchronous bilateral double primary lung cancer successfully treated by Nd-YAG laser therapy and chemotherapy]

A 61-year-old man was admitted to our hospital with the chief complaint of hemosputum. He was a heavy smoker. A chest radiograph revealed a tumor shadow in right S3 which invaded the pulmonary artery. There was also an associated patchy shadow in the periphery as well as ipsilateral pleural effusion. Bronchoscopy revealed a near occlusion with superficial infiltration at the right B3 bronchus and a nodular tumor at the bifurcation between the left upper and lingual division bronchi, which was consistent with endoscopic early lung cancer. Although both tumors were histologically diagnosed as squamous cell carcinoma, this was considered to be a case of synchronous double primary lung cancer due to their mutual isolation. The left tumor was subsequently diagnosed as carcinoma in situ. Following Nd-YAG laser therapy for carcinoma in situ and 4 courses of systemic chemotherapy using TXT and CDDP, bronchoscopy revealed no residual cancerous tissue and no tumor apart from the nodular shadow in right S3 was seen on a radiograph. Subsequent right upper and middle lobectomy and lymph node (R2a) dissection revealed no residual tumors.

Broader clinical spectrum of Fukuyama-type congenital muscular dystrophy manifested by haplotype analysis

Fukuyama-type congenital muscular dystrophy, Walker-Warburg syndrome, and muscle-eye-brain disease are clinically similar autosomal-recessive diseases, characterized by congenital muscular dystrophy, cobblestone lissencephaly, and eye anomalies. The classification of these disorders remains controversial. We analyzed five patients with congenital muscular dystrophy from four families who had severe eye and brain anomalies, such as retinal dysplasia and hydrocephalus, using polymorphic microsatellite markers flanking the Fukuyama-type congenital muscular dystrophy locus on chromosome 9q31. All patients were heterozygous for the Fukuyama muscular dystrophy founder haplotype with 3-kb insertion. In three cases, the other chromosome without the 3-kb insertion exhibited the same haplotype with a nonsense mutation on exon 3 of the Fukuyama gene. Thus, these three patients were compound heterozygotes for the condition. Severe eye anomalies such as retinal dysplasia or detachment and hydrocephalus could be included in the clinical spectrum of Fukuyama muscular dystrophy. The clinical spectrum of this disease is much broader than previously presumed.

Preoperative internal biliary drainage is superior to external biliary drainage in liver regeneration and function after hepatectomy in obstructive jaundiced rats

OBJECTIVE

To examine the differences in regeneration rates and functions of the liver at the time of and after hepatectomy in obstructive jaundiced rats with preoperative external and internal biliary drainage.

SUMMARY BACKGROUND DATA

The significance of biliary drainage before surgery is controversial in patients with obstructive jaundice.

METHODS

After biliary obstruction for 7 days, rats were randomly divided into three groups: obstructive jaundice and hepatectomy (OJ-Hx), external biliary drainage and hepatectomy (ED-Hx), and internal biliary drainage and hepatectomy (ID-Hx). The OJ-Hx group underwent hepatectomy without biliary drainage; the other two groups underwent hepatectomy after biliary drainage for 7 days. At the time of hepatectomy, all rats were provided with internal biliary drainage. On days 0, 1, 2, 3, and 7 after hepatectomy, the DNA synthesis rate and the concentrations of adenine nucleotides and malondialdehyde in the liver were determined as markers of the hepatic regeneration rate, energy status, and lipoperoxide concentration, respectively. Portal endotoxin concentrations were measured and serum hyaluronic acid concentrations were determined as an indicator of hepatic endothelial function.

RESULTS

The relative liver weight was significantly higher in the ID-Hx group than in the OJ-Hx group on days 1, 3, and 7 after hepatectomy and than in the ED-Hx group on days 1 and 2. The rate of hepatic DNA synthesis was significantly higher in the ID-Hx group than in the OJ-Hx and ED-Hx groups on day 1. The rate was similar in the ED-Hx and ID-Hx groups on day 2 but was significantly higher than in the OJ-Hx group. The hepatic malondialdehyde concentration was significantly higher on day 1 in the ED-Hx group than in the other two groups. It was lowest in the ID-Hx group throughout the study. Both biliary drainage procedures lowered the portal endotoxin concentration and serum hyaluronic acid concentration at the time of hepatectomy. The serum hyaluronic acid concentration was lowest in the ID Hx group. Hepatic adenine triphosphate concentrations and energy charge levels were similar among the three groups.

CONCLUSION

Although both external and internal biliary drainage before hepatectomy improved serum liver function tests, portal endotoxin concentration, and serum hyaluronic acid concentration at the time of surgery, preoperative internal biliary drainage was superior to external drainage, as evidenced by the better liver regeneration and function after hepatectomy.

Prevalence and genetic diversity of cagD, cagE, and vacA in Helicobacter pylori strains isolated from Japanese patients

BACKGROUND

Although cagD and cagE (cagDE) identified upstream of cagA have been shown to be involved in the induction of interleukin (IL)-8 expression, the relationship between cagDE status and gastroduodenal diseases still remains to be examined. Thus we investigated prevalence and genetic diversity of cagD, cagE, and vacA in Helicobacter pylori strains isolated from patients with peptic ulcer or gastritis.

METHODS

We analyzed 73 H. pylori strains isolated from Japanese patients (gastritis (GA), 15; gastric ulcer (GU), 28; duodenal ulcer (DU), 23; GU and DU, 7). The presence of cagDE was evaluated by polymerase chain reaction (PCR) and Southern hybridization. The vacA genotype was examined by PCR, using type-specific primers.

RESULTS

cagDE was present in 13 (86.7%) of 15 patients with GA, 26 (92.9%) of 28 patients with GU, 21 (91.3%) of 23 patients with DU, and 6 (85.7%) of 7 patients with GU and DU (P = 0.89). vacA signal sequence type s1 was found in 14 (93.3%) of 15 patients with GA, 26 (92.9%) of 28 patients with GU, 22 (95.7%) of 23 patients with DU, and 6 (85.7%) of 7 patients with GU and DU (P = 0.84). Sequences of cagDE and vacA in our Japanese strains were highly homologous with one another, and there were no disease-specific mutations.

CONCLUSIONS

Most of the H. pylori strains in Japan were cagDE-positive, vacA s1 type, regardless of clinical outcome. The present study also indicated that these genes were conserved well among our H. pylori isolates.

Coronary artery disease and endothelial nitric oxide synthase and angiotensin-converting enzyme gene polymorphisms

Nitric oxide (NO) inhibits platelet aggregation, proliferation of vascular smooth muscle cells, and leukocyte adhesion to endothelial cells. Thus, genetic variation in or near NO synthase may be involved in the pathogenesis of coronary artery disease (CAD). We investigated the association between CAD and endothelial constitutive NO synthase (ecNOS) and angiotensin-converting enzyme (ACE) gene polymorphisms by polymerase chain reaction analysis. These genotypes were examined in consecutive patients with CAD (n = 40) and control subjects (n = 34). The frequency of ecNOS genotypes in the CAD group (4a/a + 4a/b: 48%; 4bb: 52%) did not differ from that in the control group (4a/a + 4a/b: 29%; 4bb: 71%). The allele frequencies of ecNOS4a and ecNOS4b also did not differ between the two groups. On the other hand, the frequency of the ACE DD genotype in the CAD group (DD: 45%; ID: 35%; II: 20%) was significantly higher than that in the control group (DD: 21%; ID: 35%; II: 44%). The frequency of the D allele in patients with CAD (0.63) was also significantly higher than in controls (0.38). Combined analysis showed that the frequency of the ecNOS genotypes in ACE DD genotype subjects (4a/a + 4a/b: 39%; 4b/b: 61%) in the CAD group was not significantly different from that in the control group (4a/a + 4a/b: 29%; 4b/b: 71%). The ACE genotype might be a predictor of CAD, while the ecNOS genotype appeared to confer no appreciable increase in the risk of CAD.

Effects of cholestyramine on hepatic cholesterol 7alpha-hydroxylase and serum 7alpha-hydroxycholesterol in the hamster

Cholestyramine increases activities of hepatic cholesterol 7alpha-hydroxylase and serum levels of 7alpha-hydroxycholesterol. To examine if serum 7alpha-hydroxycholesterol levels parallel with enzyme activity, 0, 0.5, 1, 2, 4, and 10% of cholestyramine was administered to female golden Syrian hamsters for 28 d in the dose-dependent study, and 2% cholestyramine for 0, 1, 3, 7, 14, 21, and 28 d in the time-dependent study. In the dose-dependent study, hepatic and serum cholesterol levels were significantly decreased dose-dependently when more than 0.5% of cholestyramine was fed for 28 d. Cholestyramine increased the cholesterol 7alpha-hydroxylase activity in a dose-dependent manner, while the serum 7alpha-hydroxycholesterol level was essentially unchanged. No correlation was found between the serum level and the hepatic enzyme activity. In the time-dependent study, hepatic and serum cholesterol levels markedly decreased when 2% cholestyramine was fed for longer than 3 d. The serum triglyceride level increased significantly for the first 7 d and then decreased. Cholesterol 7alpha-hydroxylase activity increased significantly as early as day 1, reached maximum activity level on day 7, and then kept the significantly high values until day 28. The serum 7alpha-hydroxycholesterol level significantly increased for the first 7 d and decreased to the pretreatment level thereafter. 7Alpha-hydroxycholesterol levels significantly correlated with serum cholesterol and triglyceride levels. We conclude that the serum 7alpha-hydroxycholesterol level does not always reflect the activity of hepatic cholesterol 7alpha-hydroxylase, when cholesterol metabolism is severely disturbed by cholestyramine.