Intra-abdominal Surgery and Intestinal Syndromes After Pelvic Radiation Therapy.

Purpose: To determine the effects of intra-abdominal surgery on the intensities of 5 radiation-induced intestinal syndromes in survivors of pelvic cancer. Methods and Materials: The analysis included 623 women born in 1927 or later who had survived cancer. They all had received external radiation therapy toward the pelvic area to treat gynecologic cancers. Information from 344 women who did not undergo irradiation, matched for age and residency, was also included. Main outcome measures after the surgical procedures were the intensity scores for 5 radiation-induced intestinal syndromes: urgency-tenesmus syndrome, fecal-leakage syndrome, excessive mucus discharge, excessive gas discharge, and blood discharge. The scores were based on symptom frequencies obtained from patient-reported outcomes and on factor loadings obtained from a previously reported factor analysis. Follow-up was 2 to 15 years after radiation therapy. Results: Among survivors of cancer, intra-abdominal surgery increased the intensity of the urgency-tenesmus syndrome, the fecal-leakage syndrome, excessive gas discharge, and blood discharge but had a negligible effect on mucus discharge. Intra-abdominal surgery had an especially negative effect on the urgency-tenesmus syndrome. Although the combination of appendectomy with 1 or more other intra-abdominal surgeries resulted in the highest score for all syndromes, appendectomy alone had weak to no effect. In women who did not undergo irradiation, a similar pattern was seen, albeit with much lower scores. Conclusions: We found intra-abdominal surgery to be a risk factor among survivors of gynecologic cancer, increasing the intensity score of 4 out of 5 radiation-induced intestinal syndromes. During radiation therapy, it may be worthwhile to pay extra attention to the dose of unwanted ionizing radiation to the intestines if the patient previously has undergone intra-abdominal surgery.

Low-grade intestinal inflammation two decades after pelvic radiotherapy.

BACKGROUND: Radiotherapy is effective in the treatment of cancer but also causes damage to non-cancerous tissue. Pelvic radiotherapy may produce chronic and debilitating bowel symptoms, yet the underlying pathophysiology is still undefined. Most notably, although pelvic radiotherapy causes an acute intestinal inflammation there is no consensus on whether the late-phase pathophysiology contains an inflammatory component or not. To address this knowledge gap, we examined the potential presence of a chronic inflammation in mucosal biopsies from irradiated pelvic cancer survivors. METHODS: We biopsied 24 cancer survivors two to 20 years after pelvic radiotherapy, and four non-irradiated controls. Using tandem mass tag (TMT) mass spectrometry and mRNA sequencing (mRNA-seq), we charted proteomic and transcriptomic profiles of the mucosal tissue previously exposed to a high or a low/no dose of radiation. Changes in the immune cell populations were determined with flow cytometry. The integrity of the protective mucus layers were determined by permeability analysis and 16S rRNA bacterial detection. FINDINGS: 942 proteins were differentially expressed in mucosa previously exposed to a high radiation dose compared to a low radiation dose. The data suggested a chronic low-grade inflammation with neutrophil activity, which was confirmed by mRNA-seq and flow cytometry and further supported by findings of a weakened mucus barrier with bacterial infiltration. INTERPRETATION: Our results challenge the idea that pelvic radiotherapy causes an acute intestinal inflammation that either heals or turns fibrotic without progression to chronic inflammation. This provides a rationale for exploring novel strategies to mitigate chronic bowel symptoms in pelvic cancer survivors. FUNDING: This study was supported by the King Gustav V Jubilee Clinic Cancer Foundation (CB), The Adlerbertska Research Foundation (CB), The Swedish Cancer Society (GS), The Swedish State under the ALF agreement (GS and CB), Mary von Sydow's foundation (MA and VP).

A Preparatory Study for a Randomized Controlled Trial of Dietary Fiber Intake During Adult Pelvic Radiotherapy.

Background: Patients undergoing pelvic radiotherapy are often advised to omit fiber-rich foods from their diet to reduce the adverse effects of treatment. Scientific evidence supporting this recommendation is lacking, and recent studies on animals and humans have suggested that there is a beneficial effect of dietary fiber for the alleviation of symptoms. Randomized controlled studies on dietary fiber intake during pelvic radiotherapy of sufficient size and duration are needed. As preparation for such a large-scale study, we evaluated the feasibility, compliance, participation rate, and logistics and report our findings here in this preparatory study. Methods: In this preparatory study of a fiber intervention trial, Swedish gynecological cancer patients scheduled for radiotherapy were recruited between January 2019 and August 2020. During the intervention, the participants filled out questionnaires and used an application. They also consumed a fiber supplement at first in powder form, later in capsules. Blood- and fecal samples were collected. The study is registered in clinicaltrials.gov (https://clinicaltrials.gov/ct2/show/NCT04534075?cond=fidura&draw=2&rank=1). Results: Among 136 approached patients, 57 started the study and the participation rate for primary outcomes was 63% (third blood sample) and 65% (third questionnaire). Barely half of the participants provided fecal samples. Providing concise and relevant information to the patients at the right time was crucial in getting them to participate and stay in the study. The most common reasons for declining participation or dropping out were the expected burden of radiotherapy or acute side effects. Tailoring the ambition level to each patient concerning the collection of data beyond the primary endpoints was an important strategy to keep the dropout rate at an acceptable level. Using capsules rather than psyllium in powder form made it much easier to document intake and to create a control group. During the course of the preparatory study, we improved the logistics and for the last 12 participants included, the participation rate was 100% for the earliest primary outcome. Conclusion: A variety of adjustments in this preparatory study resulted in an improved participation rate, which allowed us to set a final protocol and proceed with the main study.

Dietary Fiber and the Hippocampal Neurogenic Niche in a Model of Pelvic Radiotherapy.

We sought to determine whether radiation to the colorectum had an impact on parameters of hippocampal neurogenesis and, if so, whether it could be modulated by a fiber-rich diet. Male C57BL/6J mice were fed a diet containing bioprocessed oat bran or a fiber-free diet, starting two weeks before colorectal irradiation with 4 fractions of 8 Gray or sham-irradiation. Diets were then continued for 1, 6 or 18 weeks, whereafter parameters of hippocampal neurogenesis were analyzed and correlated to serum cytokine levels. No statistically significant changes in neuronal markers or cell proliferation were found at one week post-irradiation. Six weeks post-irradiation there was a decreased cell proliferation in the subgranular zone that appeared slightly more pronounced in irradiated animals on a fiber-free diet and increased numbers of immature neurons per mm2 dentate gyrus in the irradiated mice, with a statistically significant increase in mice on a fiber-rich diet. Microglial abundancy was similar between all groups. 18 weeks post-irradiation, a fiber-free diet had reduced the number of immature neurons, whereas irradiation resulted in an increase. Despite this, the population of mature neurons was stable. Analysis of serum cytokines revealed a negative correlation between MIP1-α and the number of immature neurons one week after irradiation, regardless of diet. Our findings show that pelvic radiotherapy has the potential to cause a long-lasting impact on hippocampal neurogenesis, and dietary interventions may modulate this impact. More in-depth studies on the relationship between irradiation-induced intestinal injury and brain health are warranted.

A Fiber-Rich Diet and Radiation-Induced Injury in the Murine Intestinal Mucosa.

Dietary fiber is considered a strong intestinal protector, but we do not know whether dietary fiber protects against the long-lasting mucosal damage caused by ionizing radiation. To evaluate whether a fiber-rich diet can ameliorate the long-lasting pathophysiological hallmarks of the irradiated mucosa, C57BL/6J mice on a fiber-rich bioprocessed oat bran diet or a fiber-free diet received 32 Gray in four fractions to the distal colorectum using a linear accelerator and continued on the diets for one, six or 18 weeks. We quantified degenerating crypts, crypt fission, cell proliferation, crypt survival, macrophage density and bacterial infiltration. Crypt loss through crypt degeneration only occurred in the irradiated mice. Initially, it was most frequent in the fiber-deprived group but declined to levels similar to the fiber-consuming group by 18 weeks. The fiber-consuming group had a fast response to irradiation, with crypt fission for growth or healing peaking already at one week post-irradiation, while crypt fission in the fiber-deprived group peaked at six weeks. A fiber-rich diet allowed for a more intense crypt cell proliferation, but the recovery of crypts was eventually lost by 18 weeks. Bacterial infiltration was a late phenomenon, evident in the fiber-deprived animals and intensified manyfold after irradiation. Bacterial infiltration also coincided with a specific pro-inflammatory serum cytokine profile. In contrast, mice on a fiber-rich diet were completely protected from irradiation-induced bacterial infiltration and exhibited a similar serum cytokine profile as sham-irradiated mice on a fiber-rich diet. Our findings provide ample evidence that dietary fiber consumption modifies the onset, timing and intensity of radiation-induced pathophysiological processes in the intestinal mucosa. However, we need more knowledge, not least from clinical studies, before this finding can be introduced to a new and refined clinical practice.

Neonatal gut colonization by Bifidobacterium is associated with higher childhood cytokine responses.

The gut microbiota is a major stimulus for the immune system, and late acquisition of bacteria and/or reduced complexity of the gut flora may delay adaptive immune maturation. However, it is unknown how the gut bacterial colonization pattern in human infants is related to T cell activation during early childhood. We followed 65 Swedish children in the FARMFLORA cohort, from birth up to 3 years of age. In fecal samples collected at several time points during the first year of life, the gut colonization pattern was investigated with the use of both 16S rRNA next generation sequencing (NGS) and culture-based techniques. This was related to production of IL-13, IL-5, IL-6, TNF, IL-1ß and IFN-γ by PHA-stimulated fresh mononuclear cells and to proportions of CD4+ T cells that expressed CD45RO at 36 months of age. Both NGS and culture-based techniques showed that colonization by Bifidobacterium at 1 week of age associated with higher production of IL-5, IL-6, IL-13, TNF and IL-1ß at 36 months of age. By contrast, gut colonization by Enterococcus, Staphylococcus aureus or Clostridium in early infancy related inversely to induced IL-13, IL-5 and TNF at 3 years of age. Infants with elder siblings produced more cytokines and had a larger fraction of CD45RO+ T cells compared to single children. However, controlling for these factors did not abolish the effect of colonization by Bifidobacterium on immune maturation. Thus, gut colonization in early infancy affects T cell maturation and Bifidobacterium may be especially prone to induce infantile immune maturation.

Isolation, identification, and selection of strains as candidate probiotics and starters for fermentation of Swedish legumes.

BACKGROUND: The non-dairy sector is growing, fermented alternatives to dairy are sparse. Adapted starter cultures to substituting raw materials needs to be developed. OBJECTIVE: Aims of this study were to isolate, identify, and phenotypically characterize lactic acid bacteria (LAB) that inhabit Swedish legumes, and assess properties necessary for selecting strains with the ability to ferment a bean beverage and with potential health beneficial properties. DESIGN: Isolates of presumed LAB were obtained from legumes collected at Öland, Sweden. Strain diversity was assessed by repetitive polymerase chain reaction (rep-PCR). The strains were identified using matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS). Species belonging to Enterococcus were predominant along with Pediococcus and closely related Bacillus. Strains were tested for tolerance to low pH, phenol, and bile as well as their bile salt hydrolase (BSH) activity. In addition, Enterococcus strains were tested for antibiotic resistance, and Pediococcus strains for their ability to ferment a bean beverage. RESULTS: From the 25 strains characterized, five were found resistant to low pH, bile, and phenol, suggesting that they can survive a passage through the gastrointestinal tract (GIT) and hence potentially exert beneficial effects in the host. These are suggested for further investigation on specific host-beneficial properties. Two of these, belonging to Pediococcus pentosaceus, were able to ferment a bean beverage without any added nutrients, indicating that the Pediococcus strains are well adapted to the bean substrate. One of the P. pentosaceus strains were also able to markedly improve the reduction of phytate by the phytase-producing yeast strain Pichia kudriavzevii TY1322 during co-fermentation as well as increase the final cell count of the yeast strain. CONCLUSION: Strain isolation and characterization performed in this study aids in selecting starter cultures for legume fermentation. Nutritional properties can be improved by co-fermentation with yeast indicating that novel nutritious fermented non-dairy products could be developed.

Are all faecal bacteria detected with equal efficiency? A study using next-generation sequencing and quantitative culture of infants' faecal samples.

BACKGROUND: Many species of intestinal bacteria are present in moderate numbers in the faecal microbiota, which is dominated by obligate anaerobes. Little is known regarding the detection sensitivity of next-generation sequencing for these microbes in samples of complex microbiota. METHODS: Twenty stool samples from six healthy infants, who were followed from 1 week to 1 year of age, were previously cultured quantitatively for total population counts, as well as for counts of relevant facultative bacteria and a limited selection of obligate anaerobes that are prevalent in the neonatal microbiota. The same samples were analysed by Next-generation sequencing (NGS, pyrosequencing) of the 16S rRNA gene (V1-V3 regions; average read length, 500 nucleotides; average number of reads per sample, 30,000). We used the bacterial culture data to determine the lowest bacterial populations that could be detected by NGS. Different DNA extraction kits (QIAamp DNA Stool Mini, ZR Faecal DNA MiniPrep, and PowerSoil DNA Isolation) were compared for efficacy in extracting DNA from Gram-negative and Gram-positive Type strains. RESULTS: NGS yielded one read per 106 CFU/g faeces of the Gram-negative commensal gut bacteria Bacteroides and Enterobacteriaceae, but only one read per 108 CFU/g faeces of Gram-positive bifidobacteria. The Gram-positive facultative bacteria Enterococcus was often undetectable by DNA-based methods despite being present at >106 CFU/g faeces. The DNA extraction kits tested varied considerably in their ability to extract DNA from bacterial samples, and showed considerably lower efficacies in extracting DNA from Gram-positive than from Gram-negative bacteria. CONCLUSIONS: NGS has lower sensitivity for detecting Gram-positive bacteria than Gram-negative bacteria, due at least in part to inefficient extraction of DNA from Gram-positive bacteria. Therefore, enzymatic lysis may enhance the yield of DNA and increase the sensitivity of NGS methods for Gram-positive bacteria, and the inclusion of positive and negative controls during DNA extraction is indicated for validation purposes. The differential extraction of DNA from bacterial samples by different DNA extraction kits may limit comparability between studies on the gut microbiota. Finally, quantitative culture methods detect certain bacteria with greater sensitivity than NGS techniques, and thus culture- and DNA-based methods can be used in tandem to define the complex composition of the gut microbiota with greater accuracy.

Dietary Oat Bran Reduces Systemic Inflammation in Mice Subjected to Pelvic Irradiation.

Patients undergoing radiotherapy to treat pelvic-organ cancer are commonly advised to follow a restricted fiber diet. However, reducing dietary fiber may promote gastrointestinal inflammation, eventually leading to deteriorated intestinal health. The goal of this study was to evaluate the influence of dietary fiber on radiation-induced inflammation. C57BL/6J male mice were fed a High-oat bran diet (15% fiber) or a No-fiber diet (0% fiber) and were either irradiated (32 Gy delivered in four fractions) to the colorectal region or only sedated (controls). The dietary intervention started at 2 weeks before irradiation and lasted for 1, 6, and 18 weeks after irradiation, at which time points mice were sacrificed and their serum samples were assayed for 23 cytokines and chemokines. Our analyses show that irradiation increased the serum cytokine levels at all the time points analyzed. The No-fiber irradiated mice had significantly higher levels of pro-inflammatory cytokines than the High-oat irradiated mice at all time points. The results indicate that a fiber-rich oat bran diet reduces the intensity of radiation-induced inflammation, both at an early and late stage. Based on the results, it seems that the advice to follow a low-fiber diet during radiotherapy may increase the risk of decreased intestinal health in cancer survivors.

Fecal short chain fatty acids in children living on farms and a link between valeric acid and protection from eczema.

Children growing up on farms have low rates of allergy, but the mechanism for this protective effect has not been fully elucidated. Short chain fatty acids (SCFAs) produced by the gut microbiota may play a role in protection from allergy. We measured fecal SCFA levels in samples collected from 28 farming and 37 control children over the first 3 years of life using gas chromatography. Data on diet and other host factors were recorded and allergy was diagnosed at 8 years of age. Among all children, median propionic and butyric acid concentration increased over the first 3 years, and longer SCFAs typically appeared by 1 year of age. Farm children had higher levels of iso-butyric, iso-valeric and valeric acid at 3 years of age than rural controls. In addition, children with elder siblings had higher levels of valeric acid at 3 years of age, and dietary factors also affected SCFA pattern. High levels of valeric acid at 3 years of age were associated with low rate of eczema at 8 years of age. The fecal SCFA pattern in farm children suggests a more rapid maturation of the gut microbiota. Valeric acid or associated microbes may have protective potential against eczema.

Long-term mucosal injury and repair in a murine model of pelvic radiotherapy.

Chronic intestinal injury after pelvic radiotherapy affects countless cancer survivors worldwide. A comprehensive understanding of the long-term injury dynamics is prevented in available animal models. With linear accelerators that are used to treat cancer in patients, we irradiated a small volume encompassing the colorectum in mice with four fractions of 8 Gy per fraction. We then determined the long-term dynamics of mucosal injury, repair, and the duration of inflammation. We show that crypt fission, not cell proliferation, is the main long-term mechanism for rescuing crypt density after irradiation, and provides a potentially wide window for clinical interventions. Persisting macrophage aggregations indicate a chronic mucosal inflammation. A better understanding as to how crypt fission is triggered and why it fails to repair fully the mucosa may help restore bowel health after pelvic radiotherapy. Moreover, anti-inflammatory interventions, even if implemented long after completed radiotherapy, could promote bowel health in pelvic cancer survivors.

Intake of citrus fruits and vegetables and the intensity of defecation urgency syndrome among gynecological cancer survivors.

BACKGROUND: Despite the experimental evidence that certain dietary compounds lower the risk of radiation-induced damage to the intestine, clinical data are missing and dietary advice to irradiated patients is not evidence-based. MATERIALS AND METHODS: We have previously identified 28 intestinal health-related symptoms among 623 gynaecological-cancer survivors (three to fifteen years after radiotherapy) and 344 matched population-based controls. The 28 symptoms were grouped into five radiation-induced survivorship syndromes: defecation-urgency syndrome, fecal-leakage syndrome, excessive mucus discharge, excessive gas discharge and blood discharge. The grouping was based on factor scores produced by Exploratory Factor Analysis in combination with the Variable Cutoff Method. Frequency of food intake was measured by a questionnaire. We evaluated the relationship between dietary intake and the intensity of the five syndromes. RESULTS: With the exception of excessive mucus discharge, the intensity of all syndromes declined with increasing intake of citrus fruits. The intensity of defecation-urgency and fecal-leakage syndrome declined with combined intake of vegetables and citrus fruits. The intensity of excessive mucus discharge was increased with increasing intake of gluten. CONCLUSION: In this observational study, we found an association between a high intake of citrus fruits and vegetables and a lower intensity of the studied radiation-induced cancer survivorship syndromes. Our data suggest it may be worthwhile to continue to search for a role of the diet before, during and after radiotherapy to help the cancer survivor restore her or his intestinal health after irradiation.

[Differing dietary advice are given to gynaecological and prostate cancer patients receiving radiotherapy in Sweden]. / Stor variation i kostråden vid strålbehandling av lilla bäckenet - Kost har potential att förebygga följdsjukdomar till strålning och ge bättre tarmhälsa ­ men vetenskaplig evidens saknas.

Preclinical studies indicate that an optimal diet during pelvic radiotherapy may be able to prevent radiation-induced survivorship diseases that diminish cancer survivors' intestinal health. We do not yet know what this optimal diet might be because scientific studies needed to determine what dietary advice might best be given to patients during treatment. Oncology clinics in Sweden were contacted to determine the nature of dietary advice given to gynaecological and prostate cancer patients at each clinic before, during and after radiotherapy. Reports from these clinics revealed that dietary advice given to patients differs from one clinic to another. This was as expected, since it was known that the scientific evidence needed to identify the best possible diet is not yet available. Clinical studies of the effects of different diets are urgently needed if we are to prevent survivorship diseases that decrease intestinal health.

Nutritional impact on Immunological maturation during Childhood in relation to the Environment (NICE): a prospective birth cohort in northern Sweden.

INTRODUCTION: Prenatal and neonatal environmental factors, such as nutrition, microbes and toxicants, may affect health throughout life. Many diseases, such as allergy and impaired child development, may be programmed already in utero or during early infancy. Birth cohorts are important tools to study associations between early life exposure and disease risk. Here, we describe the study protocol of the prospective birth cohort, 'Nutritional impact on Immunological maturation during Childhood in relation to the Environment' (NICE). The primary aim of the NICE cohort is to clarify the effect of key environmental exposures-diet, microbes and environmental toxicants-during pregnancy and early childhood, on the maturation of the infant's immune system, including initiation of sensitisation and allergy as well as some secondary outcomes: infant growth, obesity, neurological development and oral health. METHODS AND ANALYSIS: The NICE cohort will recruit about 650 families during mid-pregnancy. The principal inclusion criterion will be planned birth at the Sunderby Hospital in the north of Sweden, during 2015-2018. Questionnaires data and biological samples will be collected at 10 time-points, from pregnancy until the children reach 4 years of age. Samples will be collected primarily from mothers and children, and from fathers. Biological samples include blood, urine, placenta, breast milk, meconium, faeces, saliva and hair. Information regarding allergic heredity, diet, socioeconomic status, lifestyle including smoking, siblings, pet ownership, etc will be collected using questionnaires. Sensitisation to common allergens will be assessed by skin prick testing and allergic disease will be diagnosed by a paediatrician at 1 and 4 years of age. At 4 years of age, the children will also be examined regarding growth, neurobehavioural and neurophysiological status and oral health. ETHICS AND DISSEMINATION: The NICE cohort has been approved by the Regional Ethical Review Board in Umeå, Sweden (2013/18-31M). Results will be disseminated through peer-reviewed journals and communicated on scientific conferences.

Dose-response relationships of the sigmoid for urgency syndrome after gynecological radiotherapy.

PURPOSE: To find out what organs and doses are most relevant for 'radiation-induced urgency syndrome' in order to derive the corresponding dose-response relationships as an aid for avoiding the syndrome in the future. MATERIAL AND METHODS: From a larger group of gynecological cancer survivors followed-up 2-14 years, we identified 98 whom had undergone external beam radiation therapy but not brachytherapy and not having a stoma. Of those survivors, 24 developed urgency syndrome. Based on the loading factor from a factor analysis, and symptom frequency, 15 symptoms were weighted together to a score interpreted as the intensity of radiation-induced urgency symptom. On reactivated dose plans, we contoured the small intestine, sigmoid colon and the rectum (separate from the anal-sphincter region) and we exported the dose-volume histograms for each survivor. Dose-response relationships from respective risk organ and urgency syndrome were estimated by fitting the data to the Probit, RS, LKB and gEUD models. RESULTS: The rectum and sigmoid colon have steep dose-response relationships for urgency syndrome for Probit, RS and LKB. The dose-response parameters for the rectum were D50: 51.3, 51.4, and 51.3 Gy, γ50 = 1.19 for all models, s was 7.0e-09 for RS and n was 9.9 × 107 for LKB. For Sigmoid colon, D50 were 51.6, 51.6, and 51.5 Gy, γ50 were 1.20, 1.25, and 1.27, s was 2.8 for RS and n was 0.079 for LKB. CONCLUSIONS: Primarily the dose to sigmoid colon as well as the rectum is related to urgency syndrome among gynecological cancer survivors. Separate delineation of the rectum and sigmoid colon in order to incorporate the dose-response results may aid in reduction of the incidence of the urgency syndrome.

Elastase as a potential biomarker for radiation-induced gut wall injury of the distal bowel in an experimental mouse model.

BACKGROUND AND PURPOSE: Traditionally, elastase has been used to study exocrine activity of the pancreas in patients with chronic pancreatitis and cystic fibrosis, and calprotectin as a marker for gut-wall inflammation in patients with inflammatory bowel disease. The aim of the study was to find out whether elastase and calprotectin could be used as inflammatory markers for radiation-induced gut wall injury of the distal bowel. MATERIAL AND METHODS: Adult male mice were exposed to two, three, or four fractions of 6 Gy or 8 Gy irradiation to the sigmoid and rectum of the large bowel, using a linear accelerator. Fecal samples were collected from mice at 1, 3, and 6 weeks post-irradiation. The fecal levels of elastase and calprotectin were analyzed using ELISA. RESULTS: Three and 6 weeks after irradiation, we found a dose-effect relationship between dose of ionizing radiation and the fecal level of elastase; that is significantly higher levels of elastase were observed in mice that had received a high irradiation dose. We also found that irradiated mice hosted in the same cage had a comparable level (either high or low) of elastase. No significant differences were observed from the calprotectin data. CONCLUSIONS: We found a clear association between the dose of ionizing radiation to the distal colon and the level of elastase in the fecal samples.

Corrigendum: Rapid identification of intact bacterial resistance plasmids via optical mapping of single DNA molecules.

This corrects the article DOI: 10.1038/srep30410.

Low-complexity microbiota in the duodenum of children with newly diagnosed ulcerative colitis.

BACKGROUND: Inflammatory bowel disease (IBD) is characterized by gut dysbiosis. To date, the large bowel microbiota has been in focus. However, the microbiota of the small intestine may also be of importance, as the small bowel is a site for the induction and control of mucosal immune responses, which can be modulated by constituents of the local microbiota. METHODS: Duodenal fluids were collected during diagnostic work-up of treatment-naïve children who were suspected of having IBD. The duodenal fluids were analyzed by pyrosequencing (average of 32,000 reads/sample, read length of 500 nucleotides). After diagnosis, the duodenal microbiota of subjects with ulcerative colitis (N = 8) or Crohn's disease (N = 5), and non-IBD controls (N = 8) were compared. RESULTS: Pyrosequencing revealed that the duodenal microbiota of children with ulcerative colitis contained fewer Operational Taxonomic Units (OTUs) per individual than the duodenal microbiota of the controls (P = 0.005). This reduction in richness of the duodenal microbiota was seen for three major phyla: Firmicutes, Actinobacteria, and Bacteroidetes. Several bacterial genera were detected less frequently in the children with ulcerative colitis than in the non-IBD controls, including Collinsella (P = 0.001), Lactobacillus (P = 0.007), and Bacillus (P = 0.007), as well as a non-identified member of the order Sphingobacteriales (P = 0.007). CONCLUSIONS: In this pilot study, we show that the duodenal microbiota of children with ulcerative colitis exhibits reduced overall richness, despite the fact that the inflammation is primarily localized to the colon. These results should be corroborated in a larger study.

Lingual microbiota profiles of patients with geographic tongue.

Geographic tongue (GT) is an oral mucosal lesion that affects the tongue. The association between GT and the bacterial colonization profiles of the tongue is not clear. Lingual swabs were collected from lesion sites and healthy sites of 35 patients with GT (19 males and 16 females; Mage = 54.3 ± 16.1 years) and 22 controls (12 males and 10 females; Mage = 56.3 ± 15.8 years). Bacterial DNA was extracted and sequenced by next-generation sequencing. At the phylum level, Fusobacteria were significantly less abundant, while Spirochaetes were significantly more abundant in GT patients compared to controls. At the operational taxonomic units level, multivariate analysis revealed distinct clusters for the three groups based on the lingual microbiota composition. Acinetobacter and Delftia were significantly associated with GT lesion and healthy sites. However, Microbacterium, Leptospira, Methylotenera, and Lactococcus were significantly associated with GT lesion sites. Additionally, Mogibacterium and Simonsiella were significantly associated with GT healthy sites and controls. The changes in the lingual microbiota profiles of patients with GT imply a shift in the lingual bacterial ecology. However, it remains unknown if this shift is a consequence of the lesions or of factors associated with the initiation and progression of the disease.