Commensal microbiota modulate murine behaviors in a strictly contamination‐free environment confirmed by culture‐based methods

Background

There is increasing evidence suggesting the existence of an interaction between commensal microbiota, the gut and the brain. The aim of this study was to examine the influence of commensal microbiota on the host behaviors in a contamination‐free environment, which was verified by culture‐based methods.

Methods

Open‐field and marble‐burying tests were used to analyze anxiety‐like behaviors and locomotor activity in gnotobiotic BALB/c mice with a common genetic background in a sterile isolator. The monoamine levels in several regions of the brain were measured in germfree (GF) mice and commensal fecal microbiota‐associated mice (EX‐GF).

Key Results

A 24‐h exposure to the environment outside the sterile isolators rendered GF mice less anxious than those not contaminated, while there was no change in the locomotion. EX‐GF mice, the gnotobiotic mice with normal specific pathogen‐free microbiota, were less anxious and active than GF mice using open‐field and marble‐burying tests. The norepinephrine, dopamine, and serotonin turnover rates were higher in the EX‐GF mice than in the GF mice in most regions of the brain, suggesting that monoaminergic neurotransmission might increase in the EX‐GF mice comparing the GF mice. Monoassociation with Brautia coccoides reduced the anxiety level, but it did not affect the locomotor activity. In contrast, colonization with Bifidobacterium infantis decreased the locomotor activity, while having little effect on the anxiety level.

Conclusions & Inferences

These results strongly support the current view that gut microorganisms modulate brain development and behavior.     

The interactive effects of acute exercise and hypoxia on cognitive performance: A narrative review

Acute moderate intensity exercise has been shown to improve cognitive performance. In contrast, hypoxia is believed to impair cognitive performance. The detrimental effects of hypoxia on cognitive performance are primarily dependent on the severity and duration of exposure. In this review, we describe how acute exercise under hypoxia alters cognitive performance, and propose that the combined effects of acute exercise and hypoxia on cognitive performance are mainly determined by interaction among exercise intensity and duration, the severity of hypoxia, and duration of exposure to hypoxia. We discuss the physiological mechanism(s) of the interaction and suggest that alterations in neurotransmitter function, cerebral blood flow, and possibly cerebral metabolism are the primary candidates that determine cognitive performance when acute exercise is combined with hypoxia. Furthermore, acclimatization appears to counteract impaired cognitive performance during prolonged exposure to hypoxia although the precise physiological mechanism(s) responsible for this amelioration remain to be elucidated. This review has implications for sporting, occupational, and recreational activities at terrestrial high altitude where cognitive performance is essential. Further studies are required to understand physiological mechanisms that determine cognitive performance when acute exercise is performed in hypoxia.     

Pseudotumor with dominant B-lymphocyte infiltration after metal-on-metal total hip arthroplasty with a modular cup

We report a case of a patient who underwent metal-on-metal total hip arthroplasty with a modular cup and developed a pseudotumor 5 years postoperatively. Immunohistochemistry showed dominant B-lymphocyte infiltration in the periprosthetic tissue.     

Time spent in home meal preparation affects energy and food group intakes among midlife women

Time spent in meal preparation may be indicative of the healthfulness of meals and therefore with weight status. The purpose of this study was to examine the association between amount of time spent preparing meals and meal food group and nutrient content by meal occasion (breakfast, lunch, and dinner) among 1036 midlife women. Participants completed a 1-day food record and eating occasion questionnaires for each meal occasion. ANCOVA was used to identify possible associations. Approximately half of the participants reported spending <5 min preparing breakfast and lunch, and <20 min preparing dinner. Less time spent preparing breakfast was associated with lower energy and fat intakes (p<0.0001), while less time spent preparing lunch and dinner was associated with lower vegetable and sodium intakes (p<0.0001). There were no apparent differences in the association between time spent preparing meals and meal content by weight status. Nutrition education should encourage home meal preparation while stressing the selection of healthier options. The differing associations by meal occasion suggest that interventions should be tailored according to meal type.     

The usefulness of the water swallowing test and videofluorography in swallowing rehabilitation in patients with cerebrovascular disease

It has been suggested that videofluorography (VF) is useful in the diagnosis of aspiration. The aim of this study was to investigate the usefulness of the water swallowing test and VF in swallowing rehabilitation in patients with cerebrovascular disease. Fifteen patients (mean age 72.9 +/- 2.3 years) were examined. The swallowing abnormality was assessed by the water swallowing test and VF. Patients with abnormal swallowing function on the water swallowing test (Group A, n = 4) showed aspiration and silent aspiration into the trachea on VF. However, patients suspected of dysphagia on the water swallowing test (Group B, n = 11) could swallow, demonstrating the disappearance of silent aspiration, with pooling of barium in the piriform sinus on VF. All patients in Group A could not ingest any food by mouth and received percutaneous endoscopic gastrostomy or intermittent oro-esophageal tube feeding. The swallowing function in Group B improved after swallowing rehabilitation. All patients in Group B could ingest food by mouth. These findings suggest that the water swallowing test is useful for quantitative assessment of swallowing disorder and for deciding on therapy of swallowing function.     

Enhancement of murine hematopoiesis by synergistic interactions between steel factor (ligand for c-kit), interleukin-11, and other early acting factors in culture.

Entry into the cell cycle of dormant hematopoietic progenitors appears to be regulated by multiple synergistic factors, including interleukin-6 (IL-6), granulocyte colony-stimulating factor (G-CSF), IL-11, and the ligand for c-kit, which is also known as steel factor (SF). We have tested the effects of these and other hematopoietic factors on the proliferation of partially enriched dormant murine progenitors in the presence and absence of serum. In serum-containing cultures, SF and IL-11 interacted to support the formation of multilineage colonies; the level of colony formation was comparable with the colony formation supported by other effective two-factor combinations. In serum-free cultures, colony formation supported by two factors was significantly less than that in serum-containing culture and the most effective two-factor combination in serum-free culture was SF plus IL-3. In serum-free cultures, three-factor combinations consisting of SF, IL-3, and one of IL-6, G-CSF, or IL-11 yielded colony formation that was comparable with that seen in serum-containing cultures. These studies indicate that IL-11 belongs to a group of early-acting hematopoietic synergistic factors that now includes IL-6, G-CSF, and IL-11. In contrast, SF is unique among the synergistic factors in that it interacts either with growth factors such as IL-3 or GM-CSF or with synergistic factors such as IL-6, IL-11, or G-CSF.     

Elevated levels of prothrombin fragment 1 + 2 indicate high risk of thrombosis.

Prothrombin fragment 1 + 2 (F1 + 2) is considered to be useful for diagnosis of thrombosis. However, the evidence for a diagnosis of thrombosis by F1 + 2 is still not well established. The plasma concentrations of F1 + 2, soluble fibrin, D-dimer, and thrombin-antithrombin complex were measured in 694 patients suspected of having thrombosis and then were correlated with thrombosis. Plasma concentrations of F1 + 2, soluble fibrin, D-dimer, and thrombin-antithrombin complex were significantly higher in patients with thrombosis, compared with patients without thrombosis. When cutoff values of more than 300 pmol/L for F1 + 2 were used for the diagnosis, more than 50% of the patients were thus found to have thrombosis. The findings showed that F1 + 2, soluble fibrin, D-dimer, and thrombin-antithrombin complex have similar diagnostic ability. The plasma concentration of F1 + 2 closely was well correlated with thrombin-antithrombin complex, soluble fibrin, and D-dimer. Finally, F1 + 2 is one of the most useful parameters for the diagnosis of thrombosis.     

Analysis of Biochemical and Virological Efficacy of Human Lymphoblastoid Interferon (IFN) in Patients with Compensated Type C Liver Cirrhosis

A controlled trial was conducted to compare the efficacy of interferon (IFN) between two groups of patients with type C liver. Thirty-five patients were randomly assigned to group A (17 patients) or group B (18 patients). The former received 3 megaunits (MU) of human lymphoblastoid IFN six days per week for two weeks, followed by three days per week for 50 weeks; the latter group received 6 MU six days per week for two weeks followed by three days per week for 24 weeks. The percentages of biological sustained responders (B-SR) and virological sustained responders (V-SR) were 29.4 and 23.5%, respectively, in group B, and 17.6% for both in group A. The therapeutic effects were not different between two groups. HCV genotype 2 accounted for significantly higher percentage of B-SR and V-SR (both 57.1%, respectively). These findings indicate that IFN is effective in type C cirrhosis with genotype 2.     

Experience of quadrantectomy with axillary dissection without radiotherapy sustained by serial pathological examination for stage I breast cancer

Breast conserving treatment usually consists of lumpectomy and axillary dissection followed by a limited dose of irradiation so that no significant side-effects occur. However, the precision of lumpectomy depends on the surgical maneuver and pathological evaluation performed at each institution. For this reason, post-operative irradiation to the preserved breast and for the occult carcinoma in the same breast is absolutely mandatory, and effectively becomes a routine step. In 1986, we started to adopt the new breast-conservation method of quadrantectomy with axillary dissection for restricted stage I breast cancer without using radiotherapy, at the Cancer Institute Hospital, Tokyo, Japan. As an alternative to irradiation to ensure safety, we chose to administer an elaborate pathological examination on serial sections. The pathological proof has saved troublesome post-operative irradiation, and the results have shown this method to be safe and clear-cut compared to the traditional breast-conserving treatment cited in the literature. From July 1986 to December 1994, we performed 321 cases of quadrantectomy and axillary dissection (Q+Ax). If the detailed pathological examination of 5-mm serial sections revealed the stump to be negative, we did not treat the preserved breast with radiotherapy. Out of 321 cases, 247 were analyzed as being stump-negative and of these 235 did not receive radiotherapy at all. During a 5 year 4 month observation period, we have not yet encountered any local recurrence. However, we have experienced 4 cases (1.70%) in which a second cancer developed in the conserved breast. The annual incidence rate was 0.32%. These results are the best so far compared to other published world reports.