DYSMICROBISM, INFLAMMATORY BOWEL DISEASE AND THYROIDITIS: ANALYSIS OF THE LITERATURE.

The human body is colonized by a large number of microbes that are collectively referred to as the microbiota. They interact with the hosting organism and some do contribute to the physiological maintenance of the general good health thru regulation of some metabolic processes while some others are essential for the synthesis of vitamins and short-chain fatty acids. The abnormal variation, in the quality and/or quantity of individual bacterial species residing in the gastro-intestinal tract, is called “dysmicrobism”. The immune system of the host will respond to these changes at the intestinal mucosa level which could lead to Inflammatory Bowel Diseases (IBD). This inflammatory immune response could subsequently extend to other organs and systems outside the digestive tract such as the thyroid, culminating in thyroiditis. The goal of the present study is to review and analyze data reported in the literature about thyroiditis associated with inflammatory bowel diseases such as Ulcerative Colitis (UC) and Crohn’s Disease (CD). It was reported that similarities of some molecular bacterial components with molecular components of the host are considered among the factors causing IBD through an autoimmune reaction which could involve other non-immune cell types. The axis dysmicrobism-IBD-autoimmune reaction will be investigated as a possible etiopathogenic mechanism to Autoimmune Thyroiditis. If such is the case, then the employment of specific probiotic strains may represent a useful approach to moderate the immune system.

An analysis of nonlinear dynamics underlying neural activity related to auditory induction in the rat auditory cortex.

A sound interrupted by silence is perceived as discontinuous. However, when high-intensity noise is inserted during the silence, the missing sound may be perceptually restored and be heard as uninterrupted. This illusory phenomenon is called auditory induction. Recent electrophysiological studies have revealed that auditory induction is associated with the primary auditory cortex (A1). Although experimental evidence has been accumulating, the neural mechanisms underlying auditory induction in A1 neurons are poorly understood. To elucidate this, we used both experimental and computational approaches. First, using an optical imaging method, we characterized population responses across auditory cortical fields to sound and identified five subfields in rats. Next, we examined neural population activity related to auditory induction with high temporal and spatial resolution in the rat auditory cortex (AC), including the A1 and several other AC subfields. Our imaging results showed that tone-burst stimuli interrupted by a silent gap elicited early phasic responses to the first tone and similar or smaller responses to the second tone following the gap. In contrast, tone stimuli interrupted by broadband noise (BN), considered to cause auditory induction, considerably suppressed or eliminated responses to the tone following the noise. Additionally, tone-burst stimuli that were interrupted by notched noise centered at the tone frequency, which is considered to decrease the strength of auditory induction, partially restored the second responses from the suppression caused by BN. To phenomenologically mimic the neural population activity in the A1 and thus investigate the mechanisms underlying auditory induction, we constructed a computational model from the periphery through the AC, including a nonlinear dynamical system. The computational model successively reproduced some of the above-mentioned experimental results. Therefore, our results suggest that a nonlinear, self-exciting system is a key element for qualitatively reproducing A1 population activity and to understand the underlying mechanisms.

Bafilomycin A1 induces apoptosis in PC12 cells independently of intracellular pH.

PC12 cells growth-arrested with bafilomycin A1 died showing apoptotic chromatin condensation in the nuclei. The bafilomycin A1-induced chromatin condensation was preceded by neurite outgrowth (NOG), required higher concentrations of bafilomycin A1 than NOG, and was suppressed by cycloheximide and aurintricarboxylic acid. NH4Cl (10 mM), another acidotropic pH perturbing agent, neither induced apoptotic chromatin condensation by itself nor suppressed that induced by bafilomycin A1, suggesting that bafilomycin A1-induced apoptosis occurs independently of intracellular pH in PC12 cells.

A case of cigarette smoking-induced acute eosinophilic pneumonia showing tolerance.

It has been proposed that acute eosinophilic pneumonia (AEP), which is characterized by the absence of recurrence, is associated with cigarette smoking (CS), because Japanese patients with AEP are young and have a high incidence of short-term smoking history. However, there has been no direct evidence that CS causes AEP. We hypothesized that tolerance might develop against repeated resumption of smoking cigarettes in CS-induced AEP cases. In this connection, we challenged a patient with CS-induced AEP with repeated resumption of CS, and it was demonstrated that CS induced AEP in conjunction with tolerance to repeated resumption of smoking.

Inhibition of NGF-induced neurite outgrowth of PC12 cells by Bacillus cereus sphingomyelinase, a bacterial hemolysin.

Sphingomyelinase of Bacillus cereus, a bacterial hemolysin, reduced nerve growth factor (NGF)-induced neurite outgrowth of PC12 cells in a dose-dependent manner. At 200 mU/ml, sphingomyelinase repressed half the neurite outgrowth of the cells at 250 ng/ml NGF. The c-fos superinduction, one of the early responses induced by NGF, was not influenced by this treatment, suggesting that the repression by sphingomyelinase occurred via a protein kinase C-independent pathway.

Inhibition of cell growth by bafilomycin A1, a selective inhibitor of vacuolar H(+)-ATPase.

Bafilomycin A1, a potent selective inhibitor of vacuolar H(+)-ATPase, inhibited the growth of a variety of cultured cells dose-dependently, including golden hamster embryo and NIH-3T3 fibroblasts, whether or not they were transformed, and PC12 and HeLa cells. The concentration of bafilomycin A1 for 50% inhibition of cell growth ranged from 10 to 50 nM. The dose response was nearly parallel with that of the bafilomycin A1-induced lysosomal pH increase. The degree of pH increase for growth inhibition produced by bafilomycin A1 was similar to that produced by NH4Cl in which little difference was recognized in effect among cell types.

Acute eosinophilic pneumonia caused by cigarette smoking.

It has been suggested that acute eosinophilic pneumonia (AEP) is associated with cigarette smoking because in Japan, the patients with AEP are young and have a high incidence of short-term smoking history. However, there has been no direct evidence to support that cigarette smoke causes AEP. Herein is reported the first case showing the direct evidence and a long-term clinical course of cigarette smoking-induced AEP, in which tolerance to repeated resumption of smoking cigarettes might have occurred. We should pay attention to the history of cigarette smoking in seeing patients with AEP, especially in young patients.

Regression of gastric mucosa-associated lymphoid tissue lymphoma with reduced telomerase activity after eradication of Helicobacter pylori.

Recently, telomerase activity has been demonstrated in a large number of malignant tumors whereas its activity is not detected in most normal somatic cells suggesting its role in the immortalization process. Here we report the first investigation of telomerase activity in a case of gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Elevated telomerase activity was detected in biopsy specimens of the lymphoma. After eradication of Helicobacter pylori, the level of telomerase activity returned to normal with histological regression of the lymphoma. The telomerase activity was associated with the disease activity of the gastric MALT lymphoma after eradication therapy in the present case.

[A case of tsutsugamushi disease in the urban area of Komatsu City].

Most of patients with tsutsugamushi disease are diagnosed by their clinical histories suggesting the opportunities of Rickettsia infection in a rural region. We reported a 76-year-old female patient, who was considered to be infected in her house in the urban area of Komatsu City. She has shown typical clinical manifestations of tsutsugamushi disease, and was remitted successfully by oral administration of minocycline. Although specific antibodies to Rickettsia tsutsugamushi could not be detected in her serum by the complement fixation (CF) method during her clinical course, their significant elevation was confirmed by the indirect immunofluorescence (IF) method.

[Recent advance of endoscopic ultrasonography for evaluating gastroenterologic early cancer].

Lutz et al. made the first report in which ultrasonographic probe could differentiate cystic tumor from solid one. After that, endoscopic ultrasonography (EUS) have advanced rapidly in engineering and clinical application. EUS is the most accurate diagnostic method presently available to determine the depth of gastrointestinal cancer invasion. We have proposed the pattern analysis for the differentiation between cancer invasion and ulcer fibrosis, because fibrosis and cancer invasion have of the same echo level. USP is more useful and easy than EUS in cases with small and flat lesion without ulcer, and EUS should perform in remaining lesions that look like early cancer with ulcer and advanced cancer. Clinically, it is believed that the invasion of early gallbladder cancer limited to the proper muscle, the early pancreas cancer is less than 1 cm. It is also practicable with EUS to detect the these cancer easily and diagnose the local stage of gall bladder and pancreas cancer. Now we are performing IDUS (ER-US, PT-US) and 3D-EUS, and believing that these technics will be used commonly in the near future.