Remedial trial of sequential anoxic/oxic chemico-biological treatment for decontamination of extreme hexachlorocyclohexane concentrations in polluted soil.

During production of γ-hexachlorocyclohexane (γ-HCH), thousands of tons of other isomers were synthesized as byproducts, and after dumping represent sources of contamination for the environment. Several microbes have the potential for aerobic and anaerobic degradation of HCHs, and zero-valent iron is an effective remediation agent for abiotic dechlorination of HCHs, whereas the combination of the processes has not yet been explored. In this study, a sequence of anoxic/oxic chemico-biological treatments for the degradation of HCHs in a real extremely contaminated soil (10-30 g/kg) was applied. Approximately 1500 kg of the soil was employed, and various combinations of reducing and oxygen-releasing chemicals were used for setting up the aerobic and anaerobic phases. The best results were obtained with mZVI/nZVI, grass cuttings, and oxygen-releasing compounds. In this case, 80 % removal of HCHs was achieved in 129 days, and 98 % degradation was achieved after 1106 days. The analysis of HCHs and their transformation products proved active degradation when slight accumulation of the transformation product during the anaerobic phase was followed by aerobic degradation. The results document that switching between aerobic and anaerobic phases, together with the addition of grass, also created suitable conditions for the biodegradation of HCHs and monochlorobenzene/benzene by microbes.

Faecal microbiota transplantation in the treatment of recurrent intestinal Clostridioides difficile infection - a ten-year single-center experience.

Clostridioides difficile (Clostridium difficile in older taxonomy) is a gram-positive anaerobic and bacteria enabled by endospores. Clostridioides difficile is currently the main cause of nosocomial infections in developed countries. Due to the high probability of developing bacterial resistance to treatment and the numerous recurrences in multiple chronic conditions in older adults of our society it causes a widespread medical problem. Faecal microbiota transplantation (FMT) is a highly effective method for treating recurrent intestinal Clostridioides difficile infections (CDI). With this method the potential mechanism of effect is the transmission of a complex intestinal ecosystem, including vital microorganisms, from the donor to the recipient. Presenting the results of monocentric prospective monitoring: Primary aim of the study was to evaluate long-term remission (the continued absence of clinical manifestations of CDI 3 months after FMT administration). The secondary aim of the study was to monitor the short-term remission in the 7 days after FMT administration. Demographic data, information about CDI and the details of therapy were obtained and completed by the treating physician of each patient or by targeted questioning of the patient or their family. We used clinical monitoring to determine the effect of the treatment. The examinations of stool donors and the preparation for a faecal microbiota transplantation were performed according to the currently valid guidelines of the Czech Society of Infectious Diseases for the treatment of the recurrent bacterial infection Clostridioides difficile with faecal microbiota transplantation. The follow-ups took place from February 2011 to July 2021 in the gastroenterology department at the AGEL Ostrava-Vítkovice Hospital and included 116 patients with their first and subsequent recurrence of CDI that were treated with faecal bacteriotherapy. The median age of our patients was 71 years old (the youngest was 19 years old, the oldest 103 years old). 69 women and 47 men took part in the study. 56 patients had their first recurrence of CDI, 41 had a second attack, and 20 patients had a third and subsequent recurrences. In 62 patients (53.4 %), the route of FMT administration was a local enema into the left colon. With 37 patients (31.9 %) we used a colonoscopy after standard anterograde bowel preparation. With 12 patients (10.3 %) gastroscopy administration (deep into the duodenum) was used. 4 patients (3.5 %) were given a nasoenteral tube and one patient (0.9 %) was administered FMT per percutaneous endoscopic gastrostomy (PEG). We applied a frozen universal donor FMT in 81 patients (69.8 %), and a freshly prepared FMT from a person living in the same household was used in 35 patients (30.1 %). The secondary endpoint (the absence of clinical manifestations of CDI within 7 days of FMT administration) was achieved with 102 patients (87.9 %) in our study. The fulfilment of the primary endpoint (the development of long-term remission) was observed with 93 patients (80.2 %). An early administration of FMT appears to be a significant predictor of treatment effect (p = 0.05; OR 5.11; 95% CI 1.65-15.8). Faecal microbiota transplantation is an effective and safe therapy for recurrent intestinal Clostridioides difficile infection, and it respects the up-to-date guidelines for treatment. Of the 116 patients included in our study with first and subsequent CDI, we achieved long-term remission in 80.2 % of them. An early administration of FMT appears to be a significant predictor of treatment effect.