Raloxifene ameliorates detrimental enzymatic and nonenzymatic collagen cross-links and bone strength in rabbits with hyperhomocysteinemia

We demonstrate a reduction in enzymatic divalent immature and trivalent pyridinium cross-links and an increase in the nonenzymatic cross-link, pentosidine (Pen), in rabbits with methionine (Met)-induced hyperhomocysteinemia. Such detrimental cross-link formation in bone was ameliorated by raloxifene (RLX) treatment.

INTRODUCTION

Collagen cross-links are determinants of bone quality. Homocysteine (Hcys) interferes with collagen cross-linking. Because RLX is thought to ameliorate bone quality, we investigated whether RLX ameliorated hyperhomocysteinemia-induced cross-link abnormalities using a Met-rich diet rabbit model.

METHODS

We divided New Zealand white rabbits into six groups (n = 6 per group): baseline control, sham operation, sham + 1% Met diet, ovariectomy (OVX), 1% Met diet + OVX, OVX + RLX (10 mg/kg/day), and 1% Met diet + OVX + RLX. RLX was administered for 16 weeks. We measured the amount of enzymatic immature and mature pyridinium cross-links and the nonenzymatic cross-link, Pen, and correlated the cross-link content to bone strength.

RESULTS

Hcys levels were significantly higher in the Met diet groups than in the normal diet groups. Met-fed rabbits with or without OVX showed a significant reduction of enzymatic cross-links, whereas an increase in Pen was observed in Met-fed rabbits with OVX. The cross-link content of the RLX-treated Met-fed rabbits with OVX was restored to similar levels as the sham group, accompanied by an improvement of bone strength.

CONCLUSION

These results demonstrate that hyperhomocysteinemia reduced bone strength via a reduction of enzymatic cross-links and an increase of nonenzymatic cross-links. RLX may ameliorate hyperhomocysteinemia-induced detrimental cross-linking in rabbits with OVX and may improve bone strength via the amelioration of collagen cross-links.

Cerebral microvascular disease predicts renal failure in type 2 diabetes

Abnormalities in small renal vessels may increase the risk of developing impaired renal function, but methods to assess these vessels are extremely limited. We hypothesized that the presence of small vessel disease in the brain, which manifests as silent cerebral infarction (SCI), may predict the progression of kidney disease in patients with type 2 diabetes. We recruited 608 patients with type 2 diabetes without apparent cerebrovascular or cardiovascular disease or overt nephropathy and followed them for a mean of 7.5 years. At baseline, 177 of 608 patients had SCI, diagnosed by cerebral magnetic resonance imaging. The risk for the primary outcome of ESRD or death was significantly higher for patients with SCI than for patients without SCI [hazard ratio, 2.44; 95% confidence interval (CI) 1.36 to 4.38]. The risk for the secondary renal end point of any dialysis or doubling of the serum creatinine concentration was also significantly higher for patients with SCI (hazard ratio, 4.79; 95% CI 2.72 to 8.46). The estimated GFR declined more in patients with SCI than in those without SCI; however, the presence of SCI did not increase the risk for progression of albuminuria. In conclusion, independent of microalbuminuria, cerebral microvascular disease predicted renal morbidity among patients with type 2 diabetes.

A randomized study of arterial infusion chemotherapy for hepatocellular carcinoma: Low-dose 5-fluorouracil/cisplatin versus low-dose 5-fluorouracil/cisplatin/Interferon beta

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Background: Recently, efficacy of intraarterial infusion chemotherapy for advanced hepatocellular carcinoma (HCC) have been improved by combination with interferon(IFN)-alpha and 5-fluorouracil (5-FU) or 5-FU and cisplatin (FP). However, there is no report about combination chemotherapy with 5-FU, cisplatin and IFNbeta. Therefore, we examined to evaluate the efficacy and safety of combination intraarterial infusion chemotherapy with IFN-beta, 5-FU and cisplatin in patients with advanced HCC in comparison with a chemotherapy using 5- FU and cisplatin. Methods: Twelve HCC patients in advanced stage were enrolled in the study after informed consent was performed. Patients with WHO performance status greater than 2, belonging to Child-Pugh class C, or with platelet less 80 x 109/l were not eligible. They were randomly assigned to FP group (n=6) and FP-IFN group (n=6). One cycle of both regimens lasted for 4 wk. 5-FU (500 mg/day) and cisplatin (10mg/day) were administered via the proper hepatic artery for 5 consecutive days per week for 3 wk. IFNbeta (1 x 106 units) was injected via the proper hepatic artery twice a week for 3 wk. Primary and secondary end points are efficacy and safety, respectively. The effect of combination chemotherapy was evaluated in each patient after one cycle based on the reduction of tumor volume. Adverse event was based on Common Terminology Criteria for Adverse Events (CTCAE) v3.0. Results: The reduction rates in the FP group and FPI group were 16.5% and 36.2%, respectively. The response rates in the FP group and FPI group were 16.7%(CR:n=0, PR:n=1) and 66.7%(CR:n=0, PR:n=4), respectively. The efficacy in FPI group was significantly higher than that in FP group. As for safety, any severe adverse event was not observed in this study although neutropenia and thrombocytopenia were more common in FPI group than in FP group. Conclusions: These data indicate that arterial infusion chemotherapy with 5-FU/cisplatin/IFNbeta may be a promising treatment modality for advanced HCC.

No significant financial relationships to disclose.

Tubular changes in obstructed kidney of adult mice evaluated using immunohistochemistry for segment-specific marker

The main focus of the present investigation is to examine obstructed kidneys due to unilateral ureteral obstruction (UUO) model in adult mice using segment-specific tubular marker and to confirm the detailed morphological evaluation of UUO that is a typical model for the tubulointerstitial fibrosis which is an endpoint outcome of chronic renal diseases. Adult mice were subjected to UUO, and kidneys were harvested 1, 3, 7 days after surgical operation. Expansion of interstitial space both in the cortex and the medulla was confirmed 3 days after UUO by HE- and azan-staining. Interstitial fibrosis developed especially around dilated tubules. Immunohistochemistry for segment-specific antibodies revealed that the proximal tubules and the descending limb of Henle's loop did not dilate until 7 days after UUO, whereas initial dilation of the ascending limb of Henle's loop appeared to occur one day after surgery. The segment from the distal tubules to the collecting ducts began dilating one day after surgery and afterward significantly dilated. The downstream segment of nephron was involved in dilating earlier than the upstream of nephron in obstructed kidney examined in the present study. Moreover, the tubules accompanying apoptosis of tubular epithelia significantly dilated compared with those without apoptotic tubular epithelia. From the above-mentioned findings, we conclude that tubular dilatation of distal segment (from the ascending limb of Henle's loop to the collecting ducts) of nephron develops tubular epithelial apoptosis caused by accumulated urine, which would link to tubular disappearance and its replacement with fibrous tissue in UUO kidney of adult mice.

[Autonomic neuropathy in type-2 diabetes, lessons from Okamoto Diabetes Study]

Clinically important diabetic autonomic neuropathy includes constipation, diarrhea, neurogenic bladder, impotence, dry skin, arterio-venous shunt in the lower extremities, reduced heart rate variability with tachycardia, orthostatic hypotension, and dysautoregulation of the cerebral blood flow. To investigate the prevalence, clinical characteristics and risk factor for diabetic complications, prospective epidemiological study (Okamoto Diabetes Study) has been started since 1991. Autonomic neuropathy was judged from the results of RR interval variation (CV < or = 1.5) and/or orthostatic change of systolic blood pressure (deltaSBP > or = 30 mmHg). The prevalence of autonomic neuropathy was 28% in type-2 diabetes enrolled in the Okamoto Diabetes Study. Aging, duration of diabetes, higher systolic blood pressure and HbA1c levels were independent risk factors for autonomic neuropathy. Frequent association with macrovascular complications in the subjects with autonomic neuropathy resulted in poor prognosis, especially due to cardiovascular events. The 55 subjects (19% of the 286 subjects already died) had died suddenly. Cause of sudden death in these subjects is still unclear, but silent myocardial infarction due to autonomic neuropathy may be, at least in part, one of the major causes of unexpected sudden death in type-2 diabetes.

Neuropsychological impairment and decreased regional cerebral blood flow by interferon treatment in patients with chronic hepatitis: a preliminary study

It is well known that interferon (IFN) has various side effects including neuropsychiatric complications such as depression. We examined the relationship between neuropsychological impairment and regional cerebral blood flow (CBF) in chronic hepatitis patients treated with and without IFN-alpha. Eight patients with chronic hepatitis participated in this study. Four patients were treated with IFN-alpha (IFN group) and 4 patients were not treated (control group). The entire IFN group and half of the control group were diagnosed with hepatitis C and the rests of the control group had hepatitis B. Neuropsychological tests were conducted. The Self-Rating Depression Scale and the State-Trait Anxiety Inventory were also completed by the subjects. In addition, cerebral single photon emission computed tomography (SPECT; 3DSRT) was performed in all patients. Neuropsychological tests and SPECT were performed in the IFN group 2 months after starting IFN treatment and in the control group 2 months after starting follow-up. A significant reduction of regional CBF in the IFN group was observed in two cerebral regions (lt-angular and lt-temporal region) (P < 0.05), which have reported associations with memory and language function. In addition, the Auditory-Verbal Learning Test (AVLT), a measure of memory function, showed a decreased tendency in the IFN group. A decrease of regional CBF by IFN treatment was shown, suggesting that a decrease of regional CBF may contribute to the neuropsychological impairment by IFN treatment.

Generation of sub-30 fs ultraviolet pulses by Raman induced phase modulation in nitrogen

We demonstrate compression of ultrashort light pulses in the ultraviolet (UV) by impulsively excited molecular wave-packets in nitrogen filled in a 25 cm long hollow waveguide of 128 microm diameter. After compression with CaF2 prisms the pulse duration was determined by XFROG to be 23 fs with a time-bandwidth product of 0.50. The advantages of our technique are high efficiency and the possibility to use it also for pulses at wavelength shorter than 200 nm. The experimental observations are explained by a theoretical model.

A case of systemic lupus erythematosus with giant hepatic cavernous hemangioma

A 39-year old woman with antiphospholipid antibody positive systemic lupus erythematosus (SLE) was admitted to our department because of high fever, liver dysfunction and high level of C-reactive protein. At hospitalization, there was no anemia or jaundice. A tumor was palpable in the epigastric region, and there was tenderness in this region, but no muscular defense. There were no findings which indicated disease activity of SLE. The result of abdominal ultrasonography showed that there was a giant tumor, which occupied the majority of the left lobule of the liver, and a nonuniform ultrasound image was observed inside the tumor. The result of dynamic computed tomography (CT) showed peripheral globular enhancement, and enhancement then extended to the tumor center with time. Consequently, the patient was diagnosed with multiple hepatic hemangiomas. After admission, anemia rapidly deteriorated, and platelet count tended to decline. Therefore, intratumor hemorrhage was suspected, and emergent angiography was performed. For hemostatic purposes, transcatheter arterial embolization (TAE) and extended left hepatic lobectomy were performed. In patients with autoimmune diseases such as SLE and antiphospholipid syndromes, when thrombocytopenia is observed, care should be paid to identifying its cause, considering thrombocytopenia may be induced by hemangioma, although these cases are extremely rare.

Serine-arginine-rich nuclear protein Luc7l regulates myogenesis in mice

Using a gene trap technique, we identified a murine homologue of the yeast LUC7-like gene (Luc7l), which is a serine-arginine-rich protein (SR protein) that localizes in the nucleus through its arginine-serine-rich domain (RS domain) at the C-terminus and shows a speckled distribution pattern. Although its transcripts are widely expressed in embryos and adults, they are rarely detected in adult skeletal muscle, and Luc7l expression was found to be negatively regulated during the course of development of limb skeletal muscle, as well as during in vitro differentiation of the myoblast cell lines Sol8 and C2C12. We also demonstrated that forced expression of Luc7l protein inhibited myogenesis in vitro. Based on our results, Luc7l is thought to play an important role in the regulation of muscle differentiation.

Influence of endoscopic papillary balloon dilation and endoscopic sphincterotomy on sphincter of oddi function: a randomized controlled trial

BACKGROUND AND STUDY AIM

Endoscopic papillary balloon dilation (EPBD) is assumed to have a theoretical advantage over endoscopic sphincterotomy (EST) in preserving sphincter of Oddi function because it does not involve cutting the biliary sphincter. Although attempts have been made to study the influence of EPBD and EST on sphincter of Oddi function, there is little agreement on this issue. In this study we used a method different from those described in previous reports to clarify whether EPBD or EST preserves sphincter of Oddi function better.

PATIENTS AND METHODS

200 patients with bile duct stones who met the eligibility criteria were randomly assigned to EPBD (n = 104) or an EST (n = 96) group. Sphincter of Oddi function was estimated by measurement of the activity of pancreatic enzymes in the common bile duct (CBD). Pure bile was collected immediately before EPBD or EST, at 1 week and at 1 year after the procedure. We also statistically investigated 14 factors other than EPBD or EST that might have the potential to affect sphincter of Oddi function.

RESULTS

There was no significant difference between the baseline characteristics of the EPBD and EST groups. A total of 91 patients (46 in the EPBD group and 45 in the EST group) remained in the trial. Pure bile was collected from the CBD of 86 patients (43 EPBD and 43 EST) 1 week after the procedure. CBD stones were extracted successfully in all cases. Before the procedure, there were no significant differences in the levels of the five pancreatic enzymes between the EPBD and EST groups. At 1 week after the procedure, in both groups, there were significant increases in the levels of the five pancreatic enzymes. At 1 year after the procedure a complete series of pancreatic enzyme analyses was done in 33 patients (12 EPBD and 21 EST). There was no significant difference between the levels of the five pancreatic enzymes immediately before and 1 year after EPBD and EST. When the pancreatic enzyme levels of the two groups were directly compared, there was no significant difference at 1 year after the procedure, but the EPBD group had significantly higher levels at 1 week following the procedure.

CONCLUSION

In this study it was found that in patients with CBD stones both EPBD and EST preserve sphincter of Oddi function.

Endoscopic mucosal resection in the management of gastric carcinoid tumors

BACKGROUND AND STUDY AIMS

Gastric carcinoid tumors are a rare disease. Previously, total gastrectomy was regarded as the treatment of choice. However, differences in biological malignancy have recently led to the increased use of endoscopic mucosal resection (EMR) for treatment. We studied the outcome of EMR in patients with gastric carcinoids who were treated at our hospital and discuss the indications for endoscopic treatment.

PATIENTS AND METHODS

Between 1986 and 1999 we carried out gastric mucosal resection in five patients with gastric carcinoid tumors. The procedure used for EMR was either strip biopsy or endoscopic aspiration mucosectomy.

RESULTS

The carcinoid tumors measured 10 mm or less in four of the five patients. Two patients had type A gastritis, and all had hypergastrinemia. There was no evidence of recurrence during follow-up (range 6 - 66 months; mean 32.6 months).

CONCLUSION

EMR is useful in the management of type 1 gastric carcinoids as classified by Rindi (hypergastrinemia; tumor diameter of 10 mm or less).

Amino acid residues before the hydrophobic region which are critical for membrane translocation of the N-terminal domain of synaptotagmin II

We examined the fine structure of the type I signal-anchor sequence of synaptotagmin II, which has a 60-residue N-terminal domain followed by a hydrophobic region (H-region), focusing on the hinge region between the N-terminal and the H-regions. It was found that the charged or highly polar residues support the translocation of the N-terminal domain through the endoplasmic reticulum membrane at specific positions in the hinge. The residue requirement correlated with the turn propensity scale for transmembranes. It is suggested that a certain conformation, likely helical hairpin, in the hinge is critical for N-terminal domain translocation.

Acholeplasma laidlawii up-regulates granulysin gene expression via transcription factor activator protein-1 in a human monocytic cell line, THP-1

An antimicrobial protein granulysin is constitutively expressed in cytotoxic T lymphocytes (CTL) and natural killer (NK) cells. However, little is known about the precise regulatory mechanisms underlying granulysin gene expression. In this study, we examined the regulatory mechanisms underlying granulysin gene expression using a human monocytic cell line, THP-1, treated with Acholeplasma laidlawii. The level of granulysin mRNA expression in THP-1 cells was significantly augmented in response to stimulation with A. laidlawii. The transfection of reporter gene constructs into THP-1 cells indicated that DNA sequences between residues -329 and -239, relative to the transcriptional start site of the granulysin gene, are responsible for mediating gene induction. In addition, mutagenesis of a putative activator protein-1 (AP-1)-binding site between residues -277 and -271 in the granulysin promoter resulted in the reduction of granulysin promoter activity. Electrophoretic mobility shift assays (EMSA) demonstrated that nuclear extract prepared from A. laidlawii-treated THP-1 cells can generate specific binding to DNA oligonucleotides encompassing the AP-1-binding site, whereas unstimulated nuclear extract from the cells failed to do so. Furthermore, competition and supershift assays confirmed that A. laidlawii can induce the activation of AP-1. These results indicate that AP-1 dominantly participates in the regulation of inducible granulysin gene expression in THP-1 cells. Therefore, the finding of inducible granulysin gene expression by A. laidlawii suggests that inducible granulysin in macrophages may function as a protective weapon when microbial invasion occurs.

Role of furin in delivery of a CTL epitope of an anthrax toxin-fusion protein

Anthrax toxin lethal factor (LF) in combination with anthrax toxin protective antigen (PA) was endocytosed and translocated to the cytosol of mammalian cells. Residues 1-255 of anthrax toxin lethal factor (LFn) was fused to a cytotoxic T lymphocyte (CTL) epitope of an influenza virus. For processing the toxins, PA must be cleaved into a 63-kDa fragment (PA63) by furin, which is a subtilisin-like processing endo-protease expressed by many eukaryotic cells. To test the ability of cells treated with the LFn fusion protein plus PA to deliver the epitope, CTL assay was performed. Two types of cell lines were identified, one was able to deliver CTL epitope while the other failed to efficiently deliver the epitope. To further elucidate the differences between these cells, the role of furin in these cells was examined. Disruption of the furin gene reduced its ability to deliver the CTL epitope. Furin expression in cells capable of efficiently delivering CTL epitope was quantitatively higher than in cells unable to deliver the epitope. The results suggest that furin plays a critical role in delivery of the CTL epitope of LFn fusion protein.

Change in cytokeratin 19 fragment level according to the severity of pulmonary alveolar proteinosis

A 48-year-old man was diagnosed with primary alveolar proteinosis (PAP). Whole lung lavage was performed for treatment, and the opacity on his chest X-ray completely disappeared. The value of cytokeratin 19 fragment (CYFRA) in the serum was high at the beginning, decreased after lung lavage, and became elevated again when the disease recurred 7 months later. As PAP is thought to be a problem of surfactant secreted from type II pneumocytes, and a cytokeratin is present in the alveolar epithelial tissue, the value of serum CYFRA might be related to the severity of PAP.

Stereotactic gamma radiosurgery for pineal and related tumors

The role of gamma knife radiosurgery as an additional therapy after conventional treatments for pineal and related tumors was studied in 30 of 33 tumors with a mean follow-up of 23.3 months. Overall results showed that a complete response was obtained in 8 cases (26.7%) and the response rate was 73.3%. However, tumor progression was found in 8 cases (26.7%), of whom 7 (23.3%) died as a consequence. Germinoma and pineocytoma showed higher response and control rates (100%), and neither progression nor death occurred after gamma knife treatment. Germinoma with syncytiotrophoblastic giant cells (STGC) has been thought to have an intermediate prognosis. Two of our cases showed a partial response and another progression. Malignant germ cell tumor and pineoblastoma showed unfavorable responses and prognosis, with the response and progression rates both being 50%. Gamma knife radiosurgery was the initial treatment in three pineal tumor cases without a histological diagnosis, and one complete and two partial responses were obtained. Gamma knife radiosurgery is expected to be an effective and novel approach to pineal and related tumors, not only as an adjuvant but also as an initial treatment.

Efficient ablation by immunotoxin-mediated cell targeting of the cell types that express human interleukin-2 receptor depending on the internal ribosome entry site

BACKGROUND

Immunotoxin-mediated cell targeting (IMCT) is a technique for conditional genetic ablation of specific cell types. IMCT provides a useful approach for generating animal models for human neurodegenerative disorders. The strategy of IMCT depends on the cytotoxic activity of antiTac-based recombinant immunotoxins that selectively target cells expressing the human interleukin-2 receptor alpha-subunit (IL-2Ralpha). Transgenic mice were generated that express the IL-2Ralpha under the control of an appropriate tissue-specific gene promoter, and they were treated with the recombinant immunotoxins resulting in the ablation of the target cell types. To restrict the expression of IL-2Ralpha transgene in the cell types of interest, it is useful to knock-in the IL-2Ralpha expression cassette into the specific marker gene locus with gene targeting. Moreover, the knock-in of the IL-2Ralpha cassette located downstream of an internal ribosome entry site (IRES) into the 3'-untranslated region of the marker gene enables IL-2Ralpha expression in the restricted cell types while preserving the intact marker gene expression. However, there is a possibility that IRES-dependent expression of the receptor may be less efficient than cap-dependent expression.

METHODS AND RESULTS

The efficiency of IRES-dependent IL-2Ralpha expression and immunotoxin responsiveness of the cells expressing the receptor were examined. The IL-2Ralpha gene fused to green fluorescence protein (GFP) (IL-2R/ GFP) was used as the target receptor. Embryonic stem cell clones were isolated that carry two types of bicistronic vectors in which the IL-2R/GFP fusion gene or the chloramphenicol acetyltransferase gene was connected upstream or downstream of IRES. The expression level of IL-2R/GFP protein in the cell clones was evaluated by GFP fluorescence detection and Western blot analysis. The IRES-dependent expression produced the same level of receptor protein as cap-dependent expression. The immunotoxin responsiveness of the cloned cells was evaluated by measuring the colony-forming efficiency in medium containing various amounts of a recombinant immunotoxin. The colony-forming efficiency of the cells expressing IL-2R/ GFP through IRES-dependent expression was reduced together with increasing immunotoxin concentration in a similar dose-dependent manner to the cells expressing the receptor through cap-dependent expression.

CONCLUSIONS

The present results indicate that it is possible to effectively use the IRES-dependent expression system for IMCT. The system permits expression of the target receptor in selective cell types by introducing the IRES-driven expression cassette into the 3'-untranslated region of the marker gene locus.

Visual demonstration of calcium accumulation in human arteries of upper and lower limbs

To elucidate the calcium content of the arteries in the upper and lower limbs, the authors determined the calcium content of all the arteries in the upper and lower limbs continuously by microwave-induced plasma-atomic emission spectrometry. The subjects were an 87-yr-old man and a 72-yr-old woman. The calcium content was determined both in the arteries of the upper limbs continuously, such as the subclavian arteries and its distal arteries, and in the arteries of the lower limbs, such as the common iliac arteries and its distal arteries. The common finding that the higher accumulation of calcium occurred in the arteries of the lower limbs in comparison to the arteries of the upper limbs and extremely high accumulation of calcium occurred in the common, external, and internal iliac arteries was obtained in the two subjects. The calcium content of the arteries in the upper and lower limbs was visually demonstrated.