OBJECTIVES: As early as the Apollo 11 mission, astronauts experienced ocular, skin, and upper airway irritation after lunar dust (LD) was brought into the return cabin, drawing attention to its potential biological toxicity. However, the biological effects of LD exposure through the digestive system remain poorly understood. This study aimed to evaluate the impact of digestive exposure to lunar dust simulant (LDS) on gut microbiota and on the intestine, liver, kidney, lung, and bone in mice. METHODS: Eight-week-old female C57BL/6J mice were used. LDS was used as a substitute for lunar dust, and Shaanxi loess was used as Earth dust (ED). Mice were randomly divided into a phosphate buffered saline (PBS) group, an ED group (500 mg/kg), and a LDS group (500 mg/kg), with assessments at days 7, 14, and 28. Mice were gavaged once every 3 days, with body weight recorded before each gavage. At sacrifice, fecal samples were analyzed by 16S ribosomal RNA (rRNA) sequencing; inflammatory cytokine expression [interleukin (IL)-1β, IL-6, and tumor necrosis factor alpha (TNF-α)] in intestinal, liver, and lung tissues was measured by real-time reverse transcription PCR (real-time RT-PCR); hematoxylin and eosin (HE) staining was performed on lung, liver, and intestinal tissues; Periodic acid-Schiff (PAS) staining was used to assess the integrity of the intestinal mucus barrier, and immunohistochemical staining was performed to evaluate the expression of mucin-2 (MUC2). Serum biochemical tests assessed hepatic and renal function. Femoral bone mass was analyzed by micro-computed tomography (micro-CT); osteoblasts and osteoclasts were assessed by osteocalcin (OCN) and tartrate-resistant acid phosphatase (TRAP) staining. Bone marrow immune cell subsets were analyzed by flow cytometry. RESULTS: At day 10, weight gain was slowed in ED and LDS groups. At days 22 and 28, body weight in both ED and LDS groups was significantly lower than controls (both P<0.05). LDS exposure increased microbial species richness and diversity at day 7. Compared with the PBS and ED groups, mice in the LDS group showed increased relative abundance of Deferribacterota, Desulfobacterota, and Campylobacterota, and decreased Firmicutes, with increased Helicobacter typhlonius and reduced Lactobacillus johnsonii and Lactobacillusmurinus. HE and PAS staining of the colon showed that mucosal structural disruption and goblet cell loss were more severe in the LDS group. In addition, immunohistochemistry revealed a significant downregulation of MUC2 expression in this group (P<0.05). No obvious pathological alterations were observed in liver HE staining among the 3 groups, and none of the groups exhibited notable hepatic or renal dysfunction. HE staining of the lungs in the ED and LDS groups showed increased perivascular inflammatory cell infiltration (both P<0.05). CONCLUSIONS LDS exposure via the digestive route induces gut dysbiosis, intestinal barrier disruption, pulmonary inflammation, bone loss, and bone marrow immune imbalance. These findings indicate that LD exposure poses potential health risks during future lunar missions. Targeted restoration of beneficial gut microbiota may represent a promising strategy to mitigate LD-related health hazards.
Animals ; Dust ; Mice ; Mice, Inbred C57BL ; Dysbiosis/etiology* ; Female ; Gastrointestinal Microbiome/drug effects* ; Moon ; Liver/metabolism* ; Digestive System/microbiology* ; Lung/metabolism* ; Kidney

OBJECTIVE: To investigate the risk factors of methicillin-resistant Staphylococcus aureus(MRSA) enterocolitis after gastrointestinal surgery. METHODS: Clinical and pathological data of 17 cases with MRSA enteritis after gastrointestinal surgery from March 2015 to March 2017 at Department of General Surgery of Affiliated Drum Tower Hospital were retrospectively analyzed. INCLUSION CRITERIA: (1) age of 18 to 80 years;(2) with history of gastrointestinal surgery; (3) diarrhea symptoms within 7 days after gastrointestinal surgery; (4) use of antibiotics before diarrhea; (5) fecal smear showing a large number of gram positive cocci; (6) fecal culture suggested the presence of MRSA; (7) application of antibiotic therapy against MRSA was effective. EXCLUSION CRITERIA: (1)clostridium difficile toxin positive; (2) toxic shock syndrome caused by food poisoning. According to gender, age, and inpatient ward, 1:2 pairing was performed, and 34 patients with non-MRSA enteritis from the hospitalized cases in the same ward were selected as the control group for retrospective case-control study. There were no significant differences in the gender, age, and constitution index between two groups (all P>0.05), indicating that the two groups were comparable. The χ² test was used to perform univariate analysis on 11 factors, including the nature of the primary disease, colorectal surgery, emergency surgery, use of multiple antibiotics, preoperative bowel preparation, perioperative hormone, intraoperative intraperitoneal chemotherapy, perioperative nasogastric tube, diabetes history, intensive care unit stay, and previous infectious disease hospitalization, and then multivariate logistic regression analysis was performed. RESULTS: MRSA enteritis occurred 3 to 5 days after surgery in all the 17 cases, and 4 cases developed septic shock rapidly. Univariate analysis showed that the operation site (colorectal surgery) (χ²=4.747, P=0.029) and use of two antibiotics before MRSA enteritis (χ²=3.959, P=0.047) were associated with MRSA enteritis after gastrointestinal surgery. Multivariate logistic regression analysis revealed that colorectal surgery was the only independent risk factor for MRSA enteritis after gastrointestinal surgery(OR=5.526, 95%CI: 1.350-22.602,P=0.017), while the use of two antibiotics was not (OR=0.204, 95%CI:0.051-0.819, P=0.025). CONCLUSIONS MRSA enteritis has a rapid onset, and a high incidence of septic shock, which requires immediate attention. Colorectal surgery is an independent risk factor for MRSA enteritis.
Anti-Bacterial Agents ; Case-Control Studies ; Colorectal Surgery ; adverse effects ; Digestive System Surgical Procedures ; adverse effects ; Enterocolitis ; etiology ; microbiology ; Humans ; Methicillin-Resistant Staphylococcus aureus ; Retrospective Studies ; Risk Factors ; Staphylococcal Infections ; etiology

BACKGROUND/AIMS: The interaction between nonsteroidal anti-inflammatory drugs (NSAIDs) and Helicobacter pylori remains controversial. We retrospectively investigated whether H. pylori infection exacerbates severe gastric mucosal injury among chronic NSAID users. METHODS: From January 2010 to December 2013, a total of 245 long-term NSAID (including low-dose aspirin) users who had undergone an esophagogastroduodenoscopy and had been evaluated for H. pylori infection were enrolled at Okayama University Hospital and Tsuyama Chuo Hospital. The degree of gastric mucosal injury was assessed according to the modified Lanza score (MLS). Severe gastric mucosal injury was defined as an MLS > or =4. Univariate and multivariate logistic regression analyses were performed. RESULTS: In the univariate analysis, age > or =75 years (odds ratio [OR], 2.4; 95% confidence interval [CI], 1.3 to 4.2), H. pylori-positivity (OR, 2.0; 95% CI, 1.2 to 3.5), and the concomitant use of proton pump inhibitors (PPIs) (OR, 0.48; 95% CI, 0.26 to 0.86) were significantly associated with severe gastric mucosal injury. The multivariate analysis was adjusted by age and sex and demonstrated that H. pylori-positivity (OR, 1.8; 95% CI, 1.0 to 3.3) and the concomitant use of PPIs (OR, 0.53; 95% CI, 0.28 to 0.99) significantly contributed to severe gastric mucosal injury. CONCLUSIONS: H. pylori infection exacerbates severe gastric mucosal injury among chronic NSAID users.
Aged ; Anti-Inflammatory Agents, Non-Steroidal/*adverse effects ; Case-Control Studies ; *Disease Progression ; Endoscopy, Digestive System ; Female ; Gastric Mucosa/*drug effects/*microbiology ; Helicobacter Infections/*complications/microbiology/pathology ; *Helicobacter pylori/drug effects ; Humans ; Logistic Models ; Male ; Middle Aged ; Odds Ratio ; Proton Pump Inhibitors/adverse effects ; Retrospective Studies

OBJECTIVETo compare the impact of traditional and fast bowel preparation on the changes of gut flora in the patients following colorectal resection.

METHODSSixty patients undergoing colorectal resection from March 2010 to March 2011 in the Nanfang Hospital were randomly divided into the control group(n=27, 3 days of bowel preparation) and the experimental group(n=33, 1 day of bowel preparation). Fresh feces were collected before bowel preparation and on the first defecation after surgery. The postoperative changes in gut flora and septic complications were observed.

RESULTSGut flora disturbance was found in both groups. The postoperative population of Bifidobacterium and Lactobacillus decreased significantly(P<0.05), and the decrease was more significant in the experimental group compared to the control group(P<0.05), while E.coli and Staphylococcus were much higher than the preoperative level(P<0.05), which was more significant in the control group. The incidence of postoperative infection was 9.1%(3/33) in the experimental group, which was significantly lower than 29.6%(8/27) in the control group(P<0.05).

CONCLUSIONFast bowel preparation is effective in reducing gut flora disturbance and the incidence of postoperative infection.

Colorectal Neoplasms ; microbiology ; surgery ; Digestive System Surgical Procedures ; Enema ; methods ; Feces ; microbiology ; Female ; Humans ; Male ; Microbiota ; Middle Aged ; Postoperative Period ; Preoperative Care ; Prospective Studies

Foreign body ingestion is not uncommon in clinical practice, and it may occasionally lead to penetration injuries. Emergency physicians and radiologists sometimes fail to obtain complete histories including ingestion and may overlook the possibility of foreign body-induced complications. Herein, we report a case of stomach antrum perforation due to foreign body migration. We were unaware of the patient's history of eating the Korean delicacy "Kanjang-gaejang," which is raw crab seasoned with soy sauce. Several imaging diagnostic modalities had suggested the possibility of a malignant mass in the gastrocolic ligament area. During the operation, a crab leg was discovered as the cause of an intra-abdominal abscess. The patient underwent an antrectomy, a vagotomay, and a transverse colon wedge resection. We present this unusual case of a pseudotumorous lesion caused by ingestion of Kanjang-gaejang.
Abscess/microbiology ; Endoscopy, Digestive System ; Foreign-Body Migration/*radiography/ultrasonography ; Humans ; Male ; Middle Aged ; Omentum/*radiography/ultrasonography ; Positron-Emission Tomography ; Pyloric Antrum/radiography ; Rupture ; Stomach/injuries ; Streptococcus/isolation & purification ; Tomography, X-Ray Computed

Although it is difficult to define the term "aging" consensually, in medical fields, usually it means the progressive accumulation of irreversible degenerative changes leading to loss of homeostasis. It is supposable that there is also modest decline in the structure and function of several digestive organs. However, data about this subject are not enough. Main problem in studying aging digestive organ is that discrimination of primary senile change of the organ with secondary one from other senile diseases is not easy. That is, the prevalence of many non-digestive disorders which can badly affect the digestive functions is increasing by aging; for example, diabetes, malignancy, etc. To prove that some phenomenon is as result of pure senile change, it is necessary to exclude secondary one, but, the process is very complicated and difficult. In spite of this limitation, here, I will discuss the senile change of several digestive organs by aging, especially at the view of the gastrointestinal functions, with review of literatures.
*Aging ; Digestive System Diseases/*physiopathology ; Esophageal Diseases/physiopathology ; Humans ; Intestinal Diseases/metabolism/physiopathology ; Stomach Diseases/metabolism/microbiology/physiopathology

The human body is actually a super-organism that is composed of 10 times more microbial cells than our body cells. Metagenomic study of the human microbiome has demonstrated that there are 3.3 million unique genes in human gut, 150 times more genes than our own genome, and the bacterial diversity analysis showed that about 1000 bacterial species are living in our gut and a majority of them belongs to the divisions of Firmicutes and Bacteriodetes. In addition, most people share a core microbiota that comprises 50-100 bacterial species when the frequency of abundance at phylotype level is not considered, and a core microbiome harboring more than 6000 functional gene groups is present in the majority of human gut surveyed till now. Gut bacteria are not only critical for regulating gut metabolism, but also important for host immune system as revealed by animal studies.
Animals ; Biota ; Cell Culture Techniques ; Digestive System ; immunology ; microbiology ; Digestive System Diseases ; microbiology ; Humans ; Immune System ; Metagenome ; Obesity ; microbiology ; Symbiosis

Child ; Child, Preschool ; Constipation ; diagnosis ; physiopathology ; therapy ; Digestive System ; microbiology ; physiopathology ; Gastrointestinal Hormones ; physiology ; Gastrointestinal Motility ; physiology ; Humans

OBJECTIVESTo evaluate the essentials for successful management of entero-cutaneous fistulas and their.

METHODSWe analyzed. The therapeutic results of 1 168 cases treated in a single center from January. 1971 to December. 2000.

RESULTSIn these patients, the cure rate of fistulas was 93% and 37.1% after non-operative treatment. Most cases died of sepsis (60/65 cases, 93.2%) with a total mortality of 5.5%. In 659 cases who had undergone operation for enteric fistula, 647 (98.2%) recovered. The cure rate, mortality rate and successful rate of operation (94.2%, 4.4%, 99.7%) in the period of January. 1985 - December. 2000 were better than those (90.4%, 8.2%, 95, 5%) in the early period of January 1971 December 1984 (P < 0.05).

CONCLUSIONSThe change of therapeutic strategy, improved technique in control of sepsis, rational nutritional support and careful monitoring of vital organs are essential to the management of enteric fistulas. How to increase the spontaneous closure of fistula, the therapeutic rate of specific enteric fistula (e.g. IBD, radiation enteritis) and the operative rate of enteric fistula in the early period requires further study.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Child, Preschool ; Digestive System Fistula ; mortality ; therapy ; Female ; Humans ; Infant ; Male ; Middle Aged ; Nutritional Physiological Phenomena ; Postoperative Complications ; microbiology ; mortality ; Treatment Outcome