Amitriptyline up-regulates connexin43-gap junction in rat cultured cortical astrocytes via activation of the p38 and c-Fos/AP-1 signalling pathway

BACKGROUND AND PURPOSE

Intercellular communication via gap junctions, comprised of connexin (Cx) proteins, allow for communication between astrocytes, which in turn is crucial for maintaining CNS homeostasis. The expression of Cx43 is decreased in post-mortem brains from patients with major depression. A potentially novel mechanism of tricyclic antidepressants is to increase the expression and functioning of gap junctions in astrocytes.

EXPERIMENTAL APPROACH

The effect of amitriptyline on the expression of Cx43 and gap junction intercellular communication (GJIC) in rat primary cultured cortical astrocytes was investigated. We also investigated the role of p38 MAPK intracellular signalling pathway in the amitriptyline-induced expression of Cx43 and GJIC.

KEY RESULTS

Treatment with amitriptyline for 48 h significantly up-regulated Cx43 mRNA, protein and GJIC. The up-regulation of Cx43 was not monoamine-related since noradrenaline, 5-HT and dopamine did not induce Cx43 expression and pretreatment with α- and β-adrenoceptor antagonists had no effect. Intracellular signalling involved p38 MAPK, as amitriptyline significantly increased p38 MAPK phosphorylation and Cx43 expression and GJIC were significantly blocked by the p38 inhibitor SB 202190. Furthermore, amitriptyline-induced Cx43 expression and GJIC were markedly reduced by transcription factor AP-1 inhibitors (curcumin and tanshinone IIA). The translocation of c-Fos from the cytosol and the nucleus of cortical astrocytes was increased by amitriptyline, and this response was dependent on p38 activity.

CONCLUSION AND IMPLICATION

These findings indicate a novel mechanism of action of amitriptyline through cortical astrocytes, and further suggest that targeting this mechanism could lead to the development of a new class of antidepressants.

Pantoea agglomerans lipopolysaccharide maintains bone density in premenopausal women: a randomized, double-blind, placebo-controlled trial

Lipopolysaccharide fromPantoea agglomerans (LPSp) facilitates Ca and P turnover in chicken calvaria and femurs. This study investigated osteoporosis prevention by the oral administration of LPSp in mice and in double-blind clinical tests. Using ovariectomized (OVX) osteoporosis mice model, we investigated the effects of LPSp on the bone density and Ca concentration after ingesting LPSp-containing water for 4 weeks. Oral administration of LPSp tended to suppress the decline in the bone density and the cortical bone thickness in the OVX mice. Moreover, the Ca concentrations were maintained in the OVX-LPSp mice. The effects of LPSp on bone turnover were tested in randomized and double-blind clinical test subjects, who were healthy women aged 40-79 years. The subjects ingested either soy milk without LPSp (control group) or with LPSp (LPSp group) for 3 months. The results showed that the LPSp group on premenopause maintained their bone density compared with the control group pre- and postmenopause. Moreover, these effects were maintained for 2 months postobservation. LPSp maintains bone volume and density in vivo. Thus, a combination of soy milk and LPSp may be useful for osteoporosis prevention.

Primary cultures of rat cortical microglia treated with nicotine increases in the expression of excitatory amino acid transporter 1 (GLAST) via the activation of the α7 nicotinic acetylcholine receptor

Although the clearance of glutamate from the synapse under physiological conditions is performed by astrocytic glutamate transporters, their expression might be diminished under pathological conditions. Microglia glutamate transporters, however, might serve as a back-up system when astrocytic glutamate uptake is impaired, and could have a prominent neuroprotective function under pathological conditions. In the current study, the effect of nicotine, well known as a neuroprotective molecule, on the function of glutamate transporters in cultured rat cortical microglia was examined. Reverse transcription polymerase chain reaction and pharmacological approaches demonstrated that, glutamate/aspartate transporter (GLAST), not glutamate transporter 1 (GLT-1), is the major functional glutamate transporter in cultured cortical microglia. Furthermore, the α7 subunit was demonstrated to be the key subunit comprising nicotinic acetylcholine (nACh) receptors in these cells. Treatment of cortical microglia with nicotine led to a significant increase of GLAST mRNA expression and (14)C-glutamate uptake in a concentration- and time-dependent manner, which were markedly inhibited by pretreatment with methyllycaconitine, a selective α7 nACh receptor antagonist. The nicotine-induced expression of GLAST mRNA and protein is mediated through an inositol trisphosphate (IP3) and Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) depend intracellular pathway, since pretreatment with either xestospongin C, an IP3 receptor antagonist, or KN-93, a CaMKII inhibitor, blocked GLAST expression. Together, these findings indicate that activation of nACh receptors, specifically those expressing the α7 subunit, on cortical microglia could be a key mechanism of the neuroprotective effect of nACh receptor ligands such as nicotine.

[A case of subglottic stenosis with bridging granuloma after intubation with double-lumen endotracheal tube]

We present a case of subglottic stenosis with rare bridging granuloma after intubation with double-lumen endotracheal tube. An 81-year-old woman was diagnosed with the lung tumor and scheduled for the thoracoscopic surgery. We induced anesthesia with propofol, remifentanil and rocuronium. A 35 Fr double-lumen intratracheal tube was inserted to the trachea with some resistance, when the tube passed through the glottis. A few days later, she suffered from respiratory discomfort. An otolaryngologist examined her larynx and subglottis. Laryngoscopic examination revealed bridging granuloma leading to tracheal stenosis. Tracheostomy and resection of granuloma were performed, and her symptom improved. If we feel resistance in intubating a double-lumen endotracheal tube in a patient with a history of intubation with a tracheal tube, we should operate gently adjusting the size of the tracheal tube.

Recent progress in gene therapy for Parkinson's disease

Parkinson's disease (PD) is an age-related and the second most common neurodegenerative disorder beyond Alzheimer's disease. A neuropathological hallmark of PD is a prominent loss of dopaminergic neurons in the substantia nigra projecting into the caudate and putamen. Oral administration of L-dopa and/or dopamine agonists ameliorates cardinal motor symptoms of PD. However, an intermittent and long-term treatment with L-dopa frequently induces adverse side effects such as motor fluctuations and dyskinesia. As alternative therapeutic strategies, the following four approaches are currently under evaluation for clinical gene therapy trials in PD; 1) recombinant adeno-associated virus 2 system encoding aromatic L-amino acid decarboxylase (AADC), 2) glutamic acid decarboxylase (GAD) and 3) Neurturin, and 4) equine infectious anemia virus-based lentiviral system encoding AADC, tyrosine hydroxylase (TH) and GTP cyclohydrolase I (GCH) in a single transcriptional unit. GAD and Neurturin have been assessed in double blind placebocontrolled phase II studies; GAD showed a significant improvement in motor function, and Neurturin, although it failed to show significant effects at 12 months post-treatment, exhibited promising outcomes in additional examinations at 18 months. The other two approaches also represented significant effects in phase I or I/II studies. Adverse side effects due to surgery have not been observed. Here, we review preclinical and clinical trials encouraging further investigations of curative treatment for the patients suffering from PD.

Chronic hepatitis B--care delivery and patient knowledge in the Torres Strait region of Australia

BACKGROUND

Chronic hepatitis B (CHB) disproportionately affects Indigenous Australians. This article reports the findings of two studies in the Torres Strait and Northern Peninsula area (T&NPA) of Queensland in Australia. The aim of the first study was to assess CHB care delivery, the second assessed CHB patient knowledge about the condition.

METHODS

A pathology database search (1997-2009) identified a cohort of potential CHB patients in T&NPA. A file audit assessed care delivery for a random sample of 83 CHB patients. A survey assessed knowledge of 42 CHB patients.

RESULTS

A total of 365 hepatitis B positive patients were identified. There are gaps in patient review, monitoring, follow up and specialist referral. Patients had limited knowledge about CHB and measures to reduce its health impact.

DISCUSSION

Chronic hepatitis B affects a substantial number of Indigenous adults in the T&NPA. There is limited adherence to clinical guidelines. Improved uptake of clinical guidelines adapted for remote areas, incorporation of CHB into systematic chronic disease care, and culturally appropriate patient education resources and programs are needed.

Postoperative transient reduced diffusion in the ipsilateral striatum and thalamus

BACKGROUND AND PURPOSE

Restriction of diffusion has been reported in the early phase of secondary neuronal degeneration, such as wallerian degeneration. The purpose of this study was to investigate postoperative transient reduced diffusion in the ipsilateral striatum and thalamus as a remote effect of surgery.

MATERIALS AND METHODS

Six hundred two postoperative MR imaging examinations in 125 patients after cerebral surgery were retrospectively reviewed, focusing on the presence of reduced diffusion in the striatum and/or thalamus. The distribution of reduced diffusion in the striatum was classified into 3 groups: anterior, central, and posterior. Reduced diffusion in the thalamus was also classified on the basis of the anatomic locations of the thalamic nuclei. Further follow-up MRI was available in all patients with postoperative reduced diffusion, and acute infarctions were excluded. The patient medical records were reviewed to evaluate neurologic status.

RESULTS

Restriction of diffusion was observed in the striatum and/or thalamus ipsilateral to the surgical site in 17 patients (13.6%). The distribution of signal abnormality correlated with the location of the operation, in concordance with the architecture of the striatocortical and thalamocortical connections. Reduced diffusion was observed from days 7 to 46 after the operation, especially during days 8-21. The signal abnormalities completely resolved on follow-up examinations. The median follow-up period was 202 days (interquartile range, 76-487 days).

CONCLUSIONS

Postoperative transient reduced diffusion in the ipsilateral striatum and/or thalamus likely represents an early phase of secondary neuronal degeneration based on its characteristic distribution and time course. Clinically, this reduced diffusion should not be mistaken for postoperative ischemic injury.

Glutamatergic changes in the cerebral white matter associated with schizophrenic exacerbation

OBJECTIVE

Glutamatergic dysfunction in the brain has been implicated in the pathophysiology of schizophrenia. This study was aimed to examine several brain chemical mediators, including Glx (glutamate + glutamine), using (1)H magnetic resonance spectroscopy (MRS) in medicated patients with schizophrenia, with and without psychotic exacerbation.

METHOD

(1)H MRS was acquired in 24 patients with schizophrenia, with psychotic exacerbation; 22 patients without exacerbation; and 27 age- and sex-matched healthy volunteers. The levels of metabolites were measured in the left frontal and inferior parietal white matter and compared across the three groups.

RESULTS

The Glx level was significantly elevated in the left inferior parietal white matter in the patients with psychotic exacerbation in comparison with that in the healthy volunteers and the patients without exacerbation (P < 0.05). We also detected that there was a significant correlation between Positive and Negative Syndrome Scale-positive scale and Glx level in the left parietal white matter (r = 0.51, P < 0.001).

CONCLUSION

Higher than normal Glx levels indicate glutamatergic overactivity in the left inferior parietal white matter with schizophrenic exacerbation, a finding that is in accordance with the glutamatergic hypothesis in schizophrenia. The Glx level measured by (1)H MRS could be a biomarker for exacerbation in schizophrenia.

Study of Bandgap Profiling Control on Photovoltaic Performance in the Three Stacked Amorphous Solar Cells

A series of systematic experiments has been made on a bandgap profiling control using a-SiGe and a-SiC cells to clarify the cause for the improvement of the photovoltaic performance by the bandgap profiling in the photovoltaic active layer. It has been shown from the analysis that the most important contribution to the cell performance is an optimization of the ambipolar carrier collection by the bandgap profiling. On the basis of the results, an efficiency of 10.1% was obtained at the promising a-SiC/a-Si/ a-SiGe multi-bandgap stacked cell by the bandgap profiling.

Parasellar T2 dark sign on MR imaging in patients with lymphocytic hypophysitis

BACKGROUND AND PURPOSE

MR imaging findings of LYH and pituitary adenomas are similar, but the therapeutic strategies are completely different. The purpose of this study was to evaluate sellar and parasellar MR imaging findings in patients with both diseases, as well as characteristic clinical findings.

MATERIALS AND METHODS

Clinical findings, including endocrinologic study and MR images of 20 patients with LYH and 22 patients with pituitary adenoma, were retrospectively reviewed. We evaluated the MR images in relation to the following: 1) the PPHI on T1-weighted images, 2) thickened stalk (>3.5 mm), 3) pituitary symmetry, 4) pituitary enhancement pattern, 5) a dural tail, and 6) parasellar signal intensity on T2- and T1-weighted images.

RESULTS

Between patients with LYH and those with pituitary adenoma, a significant difference was identified for the number of patients with loss of PPHI, thickened stalk, pituitary symmetry, homogeneous enhancement, and parasellar dark signal intensity on T2-weighted images by statistical analysis (Fisher exact probability test, P < .05). Among them, only parasellar dark signal intensity on T2-weighted images had no false-positive cases.

CONCLUSIONS

The parasellar T2 dark sign can be a specific finding used to distinguish pituitary adenoma from LYH.

Diffusion abnormalities and reduced volume of the ventral cingulum bundle in agenesis of the corpus callosum: a 3T imaging study

BACKGROUND AND PURPOSE

Patients with agenesis of the corpus callosum (AgCC) exhibit cognitive and behavioral impairments that are not replicated by surgical transection of the callosum, suggesting that other anatomic changes may contribute to the observed clinical findings. The purpose of this study was to determine whether the ventral cingulum bundle (VCB) is affected in patients with AgCC by using diffusion tensor imaging (DTI) and volumetry.

MATERIALS AND METHODS

Twelve participants with AgCC (8 males and 4 females; mean age, 30 +/- 20) and 12 control subjects matched for age and sex (mean age, 37 +/- 19) underwent MR imaging and DTI at 3T. 3D fiber tracking of the VCB was generated from DTI and the average fractional anisotropy (FA) was computed for the tracked fibers. Additionally, the volume, cross-sectional area, and length of the VCB were measured by manually drawn regions of interest on thin-section coronal T1-weighted images. The Student t test was used to compare these results.

RESULTS

Compared with controls, subjects with AgCC demonstrated significantly reduced FA in the right VCB (P = .0098) and reduced volume and cross-sectional areas of both the left and right VCB (P < .001 for all metrics). The length of the VCB was also significantly reduced in the complete AgCC subgroup compared with controls (P = .030 in the right and P = .046 in the left, respectively).

CONCLUSIONS

Patients with AgCC have abnormal microstructure and reduced volume of the VCB, suggesting that abnormalities in intrahemispheric white matter tracts may be an important contributor to the clinical syndrome in patients with AgCC.

Clinical outcome and prognostic factors in borderline tumors of the ovary. Results from 17 years' experience in the Kinki District of Japan (1990-2006)

PURPOSE OF INVESTIGATION

The clinical characteristics and long-term prognostic factors of borderline ovarian tumors (BOTs) were evaluated.

METHODS

Data from patients who were treated for BOTs in the Kinki District of Japan from 1990 to 2006 were revieved. Two hundred and twenty-two cases were retrospectively investigated for stage, surgical procedure, histopathological features, adjuvant chemotherapy and prognosis.

RESULTS

FIGO stages included 212 patients with Stage I disease, three with Stage II and seven with Stage III. One hundred and sixty-nine cases were diagnosed as mucinous tumor, 47 were serous, and six were others. Radical surgery was performed in 136 patients and conservative surgery in 86 patients. Only two patients showed invasive peritoneal implants. Forty patients received adjuvant chemotherapy. The survival rate was 95% at ten-years. Statistical analysis showed that earlier stage, absence of residual tumors, peritoneal implants, ovarian stromal involvement, and negative peritoneal cytology were associated with significantly better overall survival.

CONCLUSION

The prognosis of patients with BOT is excellent. There are insufficient data to support a role for aggressive surgery and adjuvant chemotherapy for the possibility of prolonged survival.

Quantitative analysis of propionibacterial DNA in bronchoalveolar lavage cells from patients with sarcoidosis

BACKGROUND AND AIM OF THE WORK

The causes of sarcoidosis are still unknown. Propionibacterial subspieces are thought to be one of the most likely sources of antigens. Here we attempted to measure the amount of propionibacterial DNA in bronchoalveolar lavage (BAL) cell samples from patients with sarcoidosis and other pulmonary diseases.

METHODS

We examined BAL cells from 42 patients with sarcoidosis and 30 controls. Using quantitative polymerase chain reaction (PCR) for 16S rRNA of Propionibacterium acnes (P. acnes) and Propionibacterium granulosum (P. granulosum), we measured the amount of propionibacterial DNA in 500 ng of total DNA extracted from BAL cells from patients with sarcoidosis or other lung diseases. The correlation between clinical findings and the results of quantitative PCR were analyzed.

RESULTS

The mean level of P. acnes DNA from patients with sarcoidosis was 59.9 genomes per 500 ng of total DNA, which was significantly higher than that in controls (20.7 genomes, p<0.000l). The mean level of P. granulosum DNA from patients with sarcoidosis was 1.2 genomes, which was similar to that in controls (1.0 +/-1.6 genomes, p=0.52). The number of genomes of P. acnes in BAL cells was correlated with the serum angiotensin-converting enzyme (ACE) level and the percentage of macrophages in BAL fluid from patients with sarcoidosis.

CONCLUSIONS

The amount of P. acnes DNA in BAL cells from patients with sarcoidosis was significantly higher than that in BAL cells from patients with other pulmonary diseases. P. acnes may be involved in the pathogenesis of sarcoidosis.

[Involvement of zinc in taste disturbance occurring during treatment for malignant tumor in the chest and the effects of polaprezinc oral disintegrating tablets (a retrospective study)]

We analyzed the correlation between serum zinc levels and taste disturbance, and between patient backgrounds and serum zinc levels or taste disturbance, and evaluated the effects of polaprezinc oral disintegrating tablets on taste disturbance in 29 patients with lung cancer and one patient with malignant pleural mesothelioma who were receiving chemotherapy. Taste disturbance developed in 11 (36.7%) out of 30 patients. Serum zinc levels significantly correlated with taste disturbance (p=0.0227). Serum zinc levels were significantly lower (p=0.0235) and taste disturbance tended to be more frequent (p=0.0625) in males. Polaprezinc improved taste disturbance in 5 of 8 patients.

Aberrant midsagittal fiber tracts in patients with hemimegalencephaly

BACKGROUND AND PURPOSE

In hemimegalencephaly, MR imaging often reveals midsagittal bandlike structures between the 2 lateral ventricles. To determine whether these structures are aberrant midsagittal fibers, we retrospectively reviewed them on conventional MR imaging and prospectively examined them by diffusion tensor MR and fiber tract (FT) reconstruction imaging.

MATERIALS AND METHODS

We retrospectively reviewed conventional MR images of 26 consecutive patients with hemimegalencephaly by 2 neuroradiologists, focusing on abnormal midsagittal structures. The distance between the 2 anterior horns and widths of midsagittal bandlike structures were measured. Prospective analysis was performed in 7 consecutive patients with hemimegalencephaly examined for midsagittal aberrant fibers by diffusion tensor imaging, and cortical distribution areas of the fibers were observed.

RESULTS

The distance between the 2 anterior horns was wide (>4 mm) due to white matter-intensity structures in 20 of 26 patients (76.9%). Mid-sagittal bandlike structures were observed in 15 patients (57.7%). Asymmetry of the fornices was detected in 7 patients (26.9%), and both fornices were thickened in 7 (26.9%) patients. On FT reconstruction, images showed that 4 of 7 patients with hemimegalencephaly had aberrant midsagittal fibers connecting frontal, occipital, or parietal lobes, bilaterally (n = 3) or ipsilaterally (n = 1). All 4 patients had increased width between the 2 anterior horns, and 3 of them exhibited midsagittal bandlike structures on conventional MR imaging. On the other hand, these MR imaging findings were not noted in 3 patients who did not have aberrant midsagittal fibers on diffusion tensor imaging.

CONCLUSIONS

Aberrant midsagittal FTs running intra- or interhemispherically do not infrequently exist in patients with hemimegalencephaly.