Is stool frequency associated with the richness and community composition of gut microbiota?

BACKGROUND/AIMS: Recently, a number of studies have reported that the gut microbiota could contribute to human conditions, including obesity, inflammation, cancer development, and behavior. We hypothesized that the composition and distribution of gut microbiota are different according to stool frequency, and attempted to identify the association between gut microbiota and stool frequency. METHODS: We collected fecal samples from healthy individuals divided into 3 groups according to stool frequency: group 1, a small number of defecation (≤2 times/wk); group 2, normal defecation (1 time/day or 1 time/2 day); and group 3, a large number of defecation (≥2–3 times/day). We evaluated the composition and distribution of the gut microbiota in each group via 16S rRNA-based taxonomic profiling of the fecal samples. RESULTS: Fecal samples were collected from a total of 60 individuals (31 men and 29 women, aged 34.1±5.88 years), and each group comprised 20 individuals. The microbial richness of group 1 was significantly higher than that of group 3 and tended to decrease with increasing number of defecation (P<0.05). The biological community composition was fairly different according to the number of defecation, and Bacteroidetes to Firmicutes ratio was higher in group 1 than in the other groups. Moreover, we found specific strains at the family and genus levels in groups 1 and 3. CONCLUSIONS: Bacteroidetes to Firmicutes ratio and the abundance of Bifidobacterium were different according to the stool frequency, and specific bacteria were identified in the subjects with large and small numbers of defecation, respectively. These findings suggest that stool frequency might be associated with the richness and community composition of the gut microbiota.

A Case of Salivary Gland Choristoma Mimicking Glomus Tympanicum / 대한이비인후과학회지

Salivary gland choristoma is defined as the architecturally normal salivary gland tissues found in abnormal locations. Middle ear salivary gland choristoma usually presents with conductive hearing loss. We present a case of middle ear mass with conductive hearing loss in a 6-year-old boy. A reddish mass was incidentally found behind the normal tympanic membrane. Magnetic resonance image showed the markedly enhancing lesion which was in accordance with glomus tympanicum. Preoperative angiography was performed, but supplying artery and mass was not identified. Surgical exploration was made and the mass was dissected easily without profuse bleeding. Final diagnosis was salivary gland choristoma by histopathology. We discuss the clinical features and management of middle ear salivary choristoma with the review of literature.

Isolation of Genes Specifically Expressed in Different Developmental Stages of Pleurotus ostreatus Using Macroarray Analysis

The oyster mushroom (Pleurotus ostreatus) is one of the most important edible mushrooms worldwide. The mechanism of P. ostreatus fruiting body development has been of interest both for the basic understanding of the phenotypic change of the mycelium-fruiting body and to improve breeding of the mushrooms. Based on our previous publication of P. ostreatus expressed sequence tag database, 1,528 unigene clones were used in macroarray analysis of mycelium, fruiting body and basidiospore developmental stages of P. ostreatus. Gene expression profile databases generated by evaluating expression levels showed that 33, 10, and 94 genes were abundantly expressed in mycelium, fruiting body and basidiospore developmental stages, respectively. Among them, the genes specifically expressed in the fruiting body stage were further analyzed by reverse transcription-polymerase chain reaction and Northern blot to investigate temporal and spatial expression patterns. These results provide useful information for future studies of edible mushroom development.

Effect of Casing Layer on Growth Promotion of the Edible Mushroom Pleurotus ostreatus

Various bacteria were isolated from the casing layer soil of the culture bed of P. ostreatus and their role in fruiting body induction of the edible mushroom, P. ostreatus, was investigated. Analysis of the bacterial community isolated from the casing layer soil revealed that the composition of genera and number of cultivable bacteria were different for each sterilizing treatment. Bordetella was predominant in the bulk soil whereas Flavobacterium was predominant after sterilization of the casing layer soil. Fluorescent Pseudomonas was predominant in the non-sterilized casing layer soil. Total number of the bacterial genera in the casing layer soil was higher than that in the bulk soil. In particular, an increase in the fluorescent Pseudomonas population was observed in the non-sterilized casing layer accompanied by induction of fruiting body and enhanced mushroom production yield. The results suggested that specific bacterial populations in the casing layer play an important role in the formation of primodia and the development of basidiome in P. ostreatus.

Methods of Treatment and Outcome of Primary Cerebellar Hemorrhage

We analysed a series of 35 patients with primary cerebellar hemorrhage, diagnosed by computerized tomography scanning from 1985 to 1988. They constituted 6.6% of spontaneous intracerebral hemorrhage(35 out of 530) who were admitted during the same period. There were 13 men and 22 women. The site of hemorrhage was vermis in 15 patients and hemisphere in 20 patients. On admission, the Glasgow Coma Scale(GCS) value was less than 10 in 15 patients(42.3%) and not less than 10 in 20 patients(57.1%). Quadrigeminal cistern was normal in 11 patients(31.4%), partially obliterated in 15 patients(42.9%) and completely obliterated in 9 patients(25.7%). The largest diameter of the hematoma was less than 3cm in 15 patients(42.9%) and larger than 3cm in 20 patients(57.2%). Hydrocephalic change was observed in 21 patients(60%). The hematoma was removed via suboccipital craniectomy in 16 patients(45.7%) and managed conservatively in 11 patients(31.4%). In 8 patients(22.9%), external ventricular drainage was performed. The method of treatment was different according to the GCS value on admission, the status of the quadrigeminal cistern, the presence of hydrocephalic change, and the size of hematoma. Overall mortality rate was 22.9%. These results suggested that the conservative treatment can be done in patients with (1) high GCS value(not less than 10), (2) patent quadrigeminal cistern, (3) absent hydrocephalic change, and (4) small sized hematoma(less than 3cm). If not surgical treatment should be considered.

Sequential Histological Changes in Tissued Surrounding Experimental Intracerebral Hematoma (II) : Electron Microscopic Studies

In an attempt to investigate the sequential histological changes in the tissue surrounding intracerebral hematoma, and experimental model of intracerebral hematoma was made by an injection of 0.7ml of autologous whole blood, with the stereotaxic frame, into the right basal ganglia of the anesthetized adult rabbit. The total of 33 adult rabbits weighing 2.5 to 3.5kg were divided into 7 groups and sacrificed in 0.5, 3, 6, 9 and 12 hours, and 1 and 3 days after the formation of intracerebral hematomas. The sequential electron microscopical changes in the brain tissue surrounding hematoma were observed. The results obtained were as follows. 1) Degeneration of axon and glial cell were observed. 2) Degeneration of glial cell began to appear in 3 hours and was aggravated in 12 hours, and glial cell necrosis occurred in 1 day. Degeneration of axon began to appear in 6 hours and was aggravated in 12 hours to 1 day, and phagocytosis of degenerating axon was observed in 3 days. 3) This experimental data suggested that the removal of intracerebral hematoma might be carried out as quickly as possible, and must be done within 12 hours whenever possible.