The effects of isoflurane on adrenomedullin-induced haemodynamic responses in pithed rats

BACKGROUND AND OBJECTIVES

Adrenomedullin is a potent vasodilatory peptide. The mechanisms of adrenomedullin-induced responses are via guanine nucleotide guanosine 5'-triphosphate-binding protein (G-protein)-coupled receptor activation and are similar to those of calcitonin gene-related peptide (CGRP). Previously, we reported that sevoflurane and isoflurane inhibit CGRP-induced haemodynamic responses. The effects of volatile anaesthetics on adrenomedullin-induced haemodynamic responses, however, are unclear. We hypothesized that the volatile anaesthetic isoflurane inhibits adrenomedullin-induced haemodynamic responses. We studied the effects of isoflurane on adrenomedullin-induced haemodynamic responses in pithed rats, which enables us to evaluate the direct cardiovascular effects of drugs without interference from centrally mediated circulatory reflexes.

METHODS

Male Wistar rats were pithed by inserting a stainless-steel rod into the spinal cord. Following median sternotomy, a flow probe was placed around the ascending aorta to measure aortic blood flow. Mean arterial pressure and cardiac output were maintained at approximately 100 mmHg and 50 mL min-1, respectively, with continuous infusion of norepinephrine. After 30 min inhalation of isoflurane (1%, or 2%) in oxygen, or only oxygen, adrenomedullin (1, 3, 10 or 30 microg kg-1) was administered intravenously.

RESULTS

Adrenomedullin administration induced a transient increase followed by a persistent decrease in mean arterial pressure and cardiac output. Isoflurane (2%) significantly inhibited the initial increase in mean arterial pressure and the later decrease in mean arterial pressure and systemic vascular resistance.

CONCLUSION

Isoflurane inhibits adrenomedullin-induced vasodilation and positive inotropic effect in pithed rats. Isoflurane might inhibit the adrenomedullin receptor-mediated response, which is a common pathway for both actions.

Wapl localization on the synaptonemal complex, a meiosis-specific proteinaceous structure that binds homologous chromosomes, in the female mouse

The wings apart-like (Wapl) protein is required to hold sister chromatids together in mitotic heterochromatin in Drosophila melanogaster. It is localized on the synaptonemal complex (SC), a meiosis-specific structure connecting one pair of sister chromatids to the homologous pair in mouse pachytene spermatocytes. The human Wapl is a cohesin-binding protein that facilitates cohesin's timely release from chromosome arms during prophase. The objective of the present study was to determine the subcellular localization of the mouse Wapl on female meiotic chromosomes at pachynema. The pachytene oocytes were isolated from foetal ovaries at 18.5 dpc and double immunostained with anti-synaptonemal complex protein 2 (SYCP2) and anti-Wapl. In the pachytene oocytes examined, mouse Wapl was colocalized with SYCP2 on the SC. Our results further implicated that Wapl might play a crucial role in meiotic chromosome remodelling at early meiosis.

Efficient gene transduction of neurons by lentivirus with enhanced neuron-specific promoters

In the field of basic and clinical neurosciences, it is important to develop a method for easy delivery and persistent expression of transgene in central neurons. We firstly generated lentiviral vectors with five kinds of neuron-specific promoters, such as synapsin I (SYN), calcium/calmodulin-dependent protein kinase II, tubulin alpha I, neuron-specific enolase and platelet-derived growth factor beta chain promoters and then novel hybrid promoters by fusing cytomegalovirus enhancer (E) to those neuron-specific promoters. Neuron-specific expression of green fluorescent protein (GFP) with those promoters was examined in vivo by injecting the lentiviral vectors into the rat neostriatum, thalamus and neocortex. Among all the promoters, SYN promoter displayed the highest specificity for neuronal expression in all the regions examined (more than 96%). Although GFP production by the hybrid promoters was about 2-4 times larger than the non-enhanced promoters, the neuronal specificity was significantly decreased in most cases. However, the neuronal specificity of E/SYN hybrid promoter exhibited the least decrease only in the thalamus. Furthermore, the transcriptional activity and neuronal specificity of E/SYN promoter were sustained for up to 8 weeks. Thus, lentivirus with E/SYN promoter is the best vector for strong persistent expression in neurons.

Mucinous adenocarcinoma associated with chronic anal fistula reconstructed by gracilis myocutaneous flaps

Mucinous adenocarcinoma associated with chronic anal fistula is extremely rare, and such tumors have often reached an advanced stage at the time of presentation. Here we report a case of mucinous adenocarcinoma associated with chronic anal fistula that involved repair with gracilis myocutaneous flaps and review other reported cases. A 67-year-old man with an approximate 30-year history of an anal fistula was referred to our hospital due to enlargement of the perianal induration accompanied by mucinous secretion and pain. Physical examination of the perianal region revealed an ulcerated and discharging lesion on the buttocks. Histologic examination of a biopsy specimen of the ulcerated lesion revealed mucinous adenocarcinoma. An abdominoperineal resection was performed with resection of the ischiorectal fossa, coccyx, part of the gluteus maximus, and the obturator internus. The extensive defect was repaired with bilateral gracilis myocutaneous flaps. The patient did not experience a decrease in the strength of hip adduction and survived for 58 months without recurrence until he died of pneumonia. The repair using myocutaneous flaps was considered to contribute to a physically active life without recurrence.

Effective sludge solubilization treatment by simultaneous use of ultrasonic and electrochemical processes

Sludge disintegration treatment by using simultaneously ultrasonic irradiation and electrolysis was investigated experimentally. A lab-scale diaphragm cell irradiated with ultrasound at a constant oscillating frequency of 20 kHz was used as a reactor. The batch experiments were carried out under different conditions of electric outputs of the ultrasonic generator, electric current for the electrolysis and different initial SS concentrations. A simultaneous treatment in the cathodic compartment without any chemical doses considerably facilitated the sludge solubilization, compared to the sonication alone. An increase in the electric current up to 400 mA under a constant ultrasonic density decreased the specific energy by 55% within the experimental range. The specific energy consumption was also reduced when the initial SS concentration increased. In addition, before carrying out the simultaneous treatment, a brief electrolysis was effective for further reduction of the specific energy and the acceleration of soluble COD generation.

Dual axonal terminations from the retrosplenial and visual association cortices in the laterodorsal thalamic nucleus of the rat

Light and electron microscopic tracing studies were conducted to assess the synaptic organization in the laterodorsal thalamic nucleus (LD) of the rat and the laminar origins of corticothalamic terminals from the retrosplenial and visual association cortices to LD. A survey of the general ultrastructure of LD revealed at least three types of presynaptic terminals identified on the basis of size, synaptic vesicle morphology, and synaptic membrane specializations: (1) small axon terminals with round synaptic vesicles (SR), which accounted for the majority of terminal profiles and made asymmetric synaptic contacts predominantly with small dendritic shafts and spines; (2) large axon terminals with round synaptic vesicles (LR), which formed asymmetric synaptic contacts mainly with large dendritic shafts; and (3) small to medium-size axon terminals with pleomorphic synaptic vesicles (SMP), which symmetrically synapsed with a wide range of postsynaptic structures from cell bodies to small dendrites. Synaptic glomeruli were identified, whereas no presynaptic dendrites were found. To characterize and identify corticothalamic terminals arising from the retrosplenial and visual association cortices that project to LD, wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) was injected into these cortices. Axons anterogradely labeled with WGA-HRP ended in both SR and LR terminals. On the other hand, dextran-tetramethylrhodamine injected into LD as a retrograde fluorescent tracer labeled large pyramidal cells of layer V as well as small round or multiform cells of layer VI in the retrosplenial and visual association cortices. These findings provide the possibility that corticothalamic terminations from cortical neurons in layer V end as LR terminals, while those from neurons in layer VI end as SR boutons.

The human papillomavirus E6 and E7 inducible oncogene, hWAPL, exhibits potential as a therapeutic target

Here we show that human papillomavirus (HPV) E6 and E7 oncoproteins induce hWAPL expression. In addition, small interfering RNA (siRNA) of hWAPL suppressed the growth of tumours derived from SiHa cells in nude mice. Thus, hWAPL may be one of the effective targets of uterine cervical cancer therapy.

Comparative study on the bio-electrochemical denitrification equipped with a multi-electrode system

Three biofilm-electrode reactors (BERs) with multiple cathodes were applied to investigate the effect of electrode configuration and flow direction on denitrification under laboratory-scale conditions. The distribution of nitrate, DO and pH varied among applied BERs, as a consequence of a different electrode position in the reactors, bringing about a difference in the performance. Flow-through configuration of electrodes with a downstream anode appears to be the most suitable configuration since nitrite did not accumulate in the effluent only in this experiment and the current-denitrification efficiency at low current densities was high. Thus, it is recommended for a low-loading operation.

Reflux esophagitis after eradication of Helicobacter pylori is associated with the degree of hiatal hernia

BACKGROUND

Several studies have shown that reflux esophagitis (RE) occurs after eradication of Helicobacter pylori. However, endoscopic findings do not allow prediction of the development of RE after successful treatment. In this study, we evaluated the relationship between the prevalence of RE after eradication therapy and the degree of hiatal hernia.

METHODS

The study comprised 148 patients who had undergone H. pylori eradication therapy over the past 5 years. The degree of RE and hiatal hernia was evaluated based on endoscopic findings. Hiatal hernia was graded according to Hill's gastroesophageal flap valve (GEFV; grades I-IV) classification. RE after eradication therapy was graded according to the Los Angeles classification system. H. pylori infection was confirmed in all patients by culture, urease test and histological examination of antral and fundic biopsy specimens.

RESULTS

Among 148 patients, there were 122 patients (82.4%) with successful and 26 (17.6%) with failed eradication therapy. RE was diagnosed in 25 (20.5%) out of 122 patients with successful therapy but only in 1 (3.8%) out of 26 patients with failed therapy (P < 0.05). After successful eradication, 25 patients had mild RE (12 with grade A, 13 with grade B). Among patients of the successful eradication group (n = 122), RE was diagnosed in 2 (5.3%) out of 38 patients without hiatal hernia and in 23 (27.4%) out of 84 patients with hiatal hernia (P = 0.0051). Furthermore, RE was diagnosed in 2 (5.3%) out of 38 patients with GEFV grade I, 13 (24.1%) out of 54 with grade II, 7 (30.4%) among 23 with grade III, and 3 (42.9%) out of 7 patients with grade IV. The pH level of gastric juice after eradication therapy was lower in the group with successful eradication than in the group with failed therapy regardless of the incidence and degree of RE.

CONCLUSIONS

There is a high incidence of RE after successful H. pylori eradication therapy. This incidence of RE was closely associated with the presence and degree of hiatal hernia and with the decrease in gastric juice pH. These findings suggest that the presence of hiatal hernia together with increase in gastric acidity are important determinant factors for the development of RE after successful H. pylori eradication therapy.

Correlations of hemoglobin index (IHb) of gastric mucosa with Helicobacter pylori (H. pylori) infection and inflammation of gastric mucosa

BACKGROUND

Helicobacter pylori (H. pylori) infection causes various gastric diseases, among them H. pylori-associated gastritis characterized by diffuse redness of the gastric mucosa. The haemoglobin index (IHb) of the fundic mucosa is an objective parameter of the extent of mucosal redness, but it is unclear whether or not IHb can be used as a diagnostic marker for H. pylori infection. The purpose of this investigation was to evaluate the correlations between IHb of the fundic mucosa and H. pylori infection, inflammatory cell infiltration, and inflammatory mediator production.

METHODS

IHb of the fundic mucosa was measured in 108 patients with various gastric diseases (group 1), and values were compared between H. pylori-positive and H. pylori-negative patients. Fifteen patients with H. pylori infection from group 1 underwent H. pylori eradication therapy and IHb was measured before and after treatment. Both IHb and inflammatory cell infiltration were assessed in 61 patients (group 2). In 31 patients from group 2, the expression of interleukin (IL)-8 and inducible nitric oxide synthase (iNOS) messenger RNA (mRNA) was assayed in gastric biopsy specimens by the reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

IHb levels were significantly higher in H. pylori-positive patients than in H. pylori-negative patients (P < 0.001). IHb was decreased at one month after the eradication of H. pylori (P < 0.001). IHb was higher in patients with infiltration by both mononuclear cells and neutrophils (P < 0.001). There was a significant correlation between the IHb level and the expression of IL-8 mRNA (P < 0.001), as well as between IHb and iNOS mRNA expression (P < 0.05).

CONCLUSIONS

There were significant correlations between IHb of the gastric mucosa and H. pylori infection, inflammatory cell infiltration, and IL-8/iNOS mRNA expression, suggesting that IHb is a reliable marker of H. pylori infection for use during follow-up endoscopy after H. pylori eradication therapy.

Interleukin-8 expression in the esophageal mucosa of patients with gastroesophageal reflux disease

BACKGROUND

It has been reported that inflammatory cell infiltration can be detected in patients with endoscopically negative gastroesophageal reflux disease (GERD) as well as those with erosive reflux esophagitis. In this study, we examined the expression of mRNA for interleukin (IL)-8, a potent chemokine for neutrophils, in the esophageal mucosa of patients with GERD and compared the results with their endoscopic findings and symptoms.

METHODS

Biopsy samples were obtained from 80 patients. Endoscopic diagnosis was performed according to the Los Angeles classification. Patients with typical symptoms such as heartburn despite normal endoscopic findings were classified as the non-erosive GERD group. Total cellular RNA was extracted from the biopsy samples and IL-8 mRNA was quantified by real-time polymerase chain reaction (PCR). Localization of IL-8 protein in the esophageal mucosa was done by immunostaining.

RESULTS

Expression of IL-8 mRNA was correlated with the endoscopic grade of esophagitis or with inflammatory cell infiltration, but not with the symptoms of the patients. Expression of IL-8 mRNA was also detected in all patients with non-erosive GERD. The level of IL-8 expression in non-erosive GERD was low compared with that in erosive GERD, but was higher than that in normal controls. IL-8 immunostaining was found in the basal layers of the esophageal mucosa. Administration of lansoprazole, a proton-pump inhibitor, decreased both IL-8 mRNA and protein levels in the esophageal mucosa.

CONCLUSION

These results suggest that IL-8 in the esophageal mucosa may be involved in the pathogenesis of esophageal inflammation, including non-erosive GERD.

An orally active matrix metalloproteinase inhibitor, ONO-4817, reduces dextran sulfate sodium-induced colitis in mice

OBJECTIVE

Over-expression of matrix metalloproteinases (MMPs) can accelerate tissue destruction and disrupt subsequent tissue repair. A dextran sulfate sodium (DSS) colitis model was established to examine the effects of MMP inhibition, by an orally active MMP inhibitor ONO-4847, on colonic inflammation.

MATERIALS AND METHODS

Acute colitis was induced in female BALB/c mice by giving 8% DSS orally in drinking water for 7 days. The animals were randomized into groups receiving different concentrations of ONO-4847 or vehicle by oral gavage every day. mRNA levels of 4 MMPs and a tissue inhibitor of MMP (TIMP-1) were measured by RT-PCR in intestinal tissue isolated from mice after DSS administration. Colonic mucosal injury and inflammation were evaluated clinically, biochemically, and histologically. The clinical disease activity index (DAI), including body weight loss, stool consistency, and blood in feces, was examined. Moreover, mucosal tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma were determined by immunoassay.

RESULTS

The intestinal expression of MMP-3, -7, 9, and -12 and TIMP-1 mRNA was upregulated after DSS administration. Shortening of the colon was significantly reversed by ONO-4847 at a dose of 30 mg/kg. DAI in DSS-treated mice was significantly lower in the ONO-4847-treated mice compared with the control mice. Histological study also showed a reduced infiltration of inflammatory cells, especially neutrophils, and reducedmucosal cell disruption in ONO-4847-treated mice compared with the control mice. The increases in tissue-associated myeloperoxidase activity and thiobarbituric acid-reactive substances after DSS administration were both significantly inhibited by co-administration with ONO-4847. ONO-4847 also inhibited increases in the mucosal TNF-alpha and IFN-gamma content after DSS administration.

CONCLUSION

Improvements in DSS colitis in response to ONO-4847 suggest that activation of MMPs contributes to the initiation/amplification of colonic inflammatory injury by mechanisms including oxidative damage as well as enhancement of inflammatory cytokine release.

Modulated hydrogen beam study of adsorption-induced desorption of deuterium from Si(100)-3×1:D surfaces

We have studied the kinetic mechanism of the adsorption-induced-desorption (AID) reaction, H+D/Si(100) --> D2. Using a modulated atomic hydrogen beam, two different types of AID reaction are revealed: one is the fast AID reaction occurring only at the beam on-cycles and the other the slow AID reaction occurring even at the beam off-cycles. Both the fast and slow AID reactions show the different dependence on surface temperature Ts, suggesting that their kinetic mechanisms are different. The fast AID reaction overwhelms the slow one in the desorption yield for 300 K < or = Ts < or = 650 K. It proceeds along a first-order kinetics with respect to the incident H flux. Based on the experimental results, both two AID reactions are suggested to occur only on the 3x1 dihydride phase accumulated during surface exposure to H atoms. Possible mechanisms for the AID reactions are discussed.

Glomerular expression of biglycan and decorin and urinary levels of decorin in primary glomerular disease

AIMS

Recent studies have suggested that small leucine-rich proteoglycans (SLRP) of the extracellular matrix play a major role in modulating the activity of growth factors and in regulating the deposition of collagens. In this study, the expression of the SLRPs biglycan and decorin in the glomeruli of patients with primary glomerular disease (minimal change disease, IgA nephropathy, and membranous nephropathy) and urine immunoreactive levels examined.

METHODS

Renal biopsy specimens were obtained from patients with minimal change disease, IgA nephropathy and membranous nephropathy. Immunohistochemical staining was performed on fresh-frozen samples using anti-biglycan and anti-decorin antibodies. Examination of urine proteoglycan excretion from a total of 26 patients and 8 normal volunteers was performed by indirect ELISA.

RESULTS

In normal kidney samples, biglycan and decorin expression was found predominantly in the intrarenal arteries and tubulointerstitium, with only minimal expression in the glomeruli. Glomerular expression of these proteoglycans in glomerular disease was unchanged in all of the 4 patients examined with minimal change disease. In the case of IgA nephropathy or membranous nephropathy, some of the patients showed minimally increased immunostaining of either biglycan or decorin, but there were no signs of simultaneous upregulation of both proteoglycans. To further examine the changes in proteoglycan expression, ELISA was performed on urine samples. Urine biglycan levels were below detection levels, but high values of urine decorin immunoreactivity were found in the patients with glomerular disease. A significant negative correlation was found between urine decorin and creatinine clearance.

CONCLUSION

These results suggest that distinct changes in the expression of the SLRPs biglycan and decorin may be seen in patients with primary glomerular disease. Moreover, the negative relationship between urine decorin levels and renal function supports the hypothesis that decorin may be involved in the pathophysiology of renal dysfunction in humans.