Anti-HELLS monoclonal antibody, clone 3H21

Folia are speleothems that resemble bells, inverted cups, or bracket fungi, and whose origins are still controversial. Cenote Zapote (an underwater cave) in the Yucatan Peninsula (Mexico), is home to some of the largest folia reported to date. These speleothems are currently growing in an active underwater system, meaning this site offers an excellent opportunity to constrain the different formation models proposed for folia, which have traditionally relied on inactive examples. In Cenote Zapote, folia are closely related to bubble trails and cupolas, suggesting an underwater CO2-degassing process. In thin section, they display a succession of columnar-open and columnar-elongated endings in micrite-dendritic fabrics. Our petrographic and geochemical results demonstrate the abiotic origin of these folia and indicate carbonate precipitation from cold water by CO2 degassing below the water table that started at least 5,210 yrs BR We conclude that these folia formed as a result of subaqueous calcite precipitation around CO2 bubbles trapped below overhanging walls of the cave. The sequential alternation of columnar and micritic fabrics can be explained by changes in the position of the halocline and H2S-rich water mass while the exceptional size is the result of carbonate precipitation from waters saturated in CaCO3 during thousans of years. Then we propose the classification of these speleothems as a subtype of folia. This subtype could be named Hells Bells, respecting its original description.

Gut microbiota is represented by different microorganisms that colonize the intestinal tract, mostly the large intestine, such as bacteria, fungi, archaea and viruses. The gut microbial balance has a key role in several functions. It modulates the host's metabolism, maintains the gut barrier integrity, participates in the xenobiotics and drug metabolism, and acts as protection against gastro-intestinal pathogens through the host's immune system modulation. The impaired gut microbiota, called dysbiosis, may be the result of an imbalance in this equilibrium and is linked with different diseases, including cancer. While most of the studies have focused on the association between microbiota and gastrointestinal adenocarcinomas, very little is known about gastroenteropancreatic (GEP) neuroendocrine neoplasms (NENs). In this review, we provide an overview concerning the complex interplay between gut microbiota and GEP NENs, focusing on the potential role in tumorigenesis and progression in these tumors.