Distribution and Identification of Fish Eggs in an Internal Wave Transport Mechanism

Internal waves have been proven to transport invertebrate larvae onshore, but there has been little indication on whether internal waves transport fish eggs. Fish eggs are typically buoyant and are often found in neustonic samples, and internal waves often cause fronts that transport oils and other light particles. This research aims to determine whether there are patterns to the distribution of fish eggs. One possibility is that offshore fish eggs can be transported onshore, to nearshore nursery habitats. Before 2003, when genetic barcoding was proposed as an identification mechanism, fish eggs could only be identified visually, using color, size, and shape. However, this method can be unreliable, so this research utilizes the COI barcoding gene to identify fish eggs to a species in samples taken in the South La Jolla State Marine Preserve, an area known to experience internal waves. Samples were taken within internal wave events and also at times without internal waves for control samples. Overall, 14 species of fish were found throughout the samples via DNA barcoding, 13 in event samples, and 7 in control samples. One sample was unable to be identified to a species, due to a higher level of species divergence from the most closely related sequenced specimen. No statistically significant differences were seen in abundance or distribution, although weak trends were seen that more fish eggs were found during event samples than in controls, and that more species were found in event samples. After calculation of diversity indices, only Simpson’s evenness showed significant differences, with event samples being more evenly distributed than control samples. Overall, fish eggs were found during internal wave fronts, indicating that they can be transported. However, insights as to how or why these eggs are transported are unclear, including whether or not the eggs are simply carried along in the fronts by accident

Gut Microbiome Impacts on the Progression ​and Treatment of Diabetes

Diabetes mellitus is an autoimmune disease that impacts millions of individuals worldwide. Diabetes is treatable and one can live a normal life with this treatment, yet there is still no cure and the exact mechanism through which it develops remains elusive. Diet, environment, genetics, and lifestyle are all factors contributing to the increasing number of diabetes cases, though genetics are being reconsidered as the primary factor. Instead, recent research has turned to the gut microbiome as both a cause of diabetes and a possible treatment and prevention option, with new data elevating the importance. However, this is controversial, because findings remain mixed and additional support is needed, as this manuscript will review. Presently, Type 1 diabetes (T1D) research has found that the microbiome can be used as a biomarker because an increase in alpha-diversity is correlated to a decreased likelihood of developing diabetes. Research has also focused on using the gut microbiome to alleviate symptoms or prevent T1D. On the other hand, Type 2 diabetes (T2D) likely has a partial cause in gut microbiome dysbiosis due to increases in gut permeability and systemic inflammation leading to insulin resistance. However, an increase in beneficial bacteria through probiotics and other dietary changes could provide a reversal of the disease state. Studies still need to be conducted to advance understanding of the exact mechanisms through which gut microbes can trigger or protect from diabetes, using further human clinical studies.  &nbsp

The cervicovaginal microbiome and its resistome in a random selection of Afro-Caribbean women

The cervicovaginal microbiome consists of community state types (CSTs) I-V. Several studies have reported positive correlations between health issues such as bacterial vaginosis (BV), acquisition of sexually transmitted infections (STIs), preterm labour and CST IV. The cervicovaginal microbiome in Afro-Caribbean women has never been characterized. Hence, this study aimed to determine the composition, CST, microbial function and resistome of the cervicovaginal microbiome in a cohort of Afro-Caribbean women using targeted (16S rRNA V4) and whole genome shotgun metagenomics. CST IV predominated in this ethnic group, with Prevotella (13.91 %) being the most abundant genus followed by Gardnerella (12.14 %). The relative abundance for Lactobacillus was 9.37 %. The most abundant species for Prevotella and Lactobacillus were P. timonensis (5.00 %) and L. iners (7.00 %), respectively. Taxa with significant nucleotide similarity to the less virulent culture collection strain G. vaginalis 409–05 (8.14 %) were more abundant than G. vaginalis ATCC 14019 (4.00 %) in this group that was asymptomatic of BV. Functional profiling revealed a high abundance of biological processes (such as flagellum-dependent cell motility, cell adhesion and quorum sensing) associated with biofilm activity. In the resistome, 2,753 predicted antimicrobial resistance (AMR) genes consisting of 28 types (mostly tet and Emr; relative abundance 52.94 % and 16.18 %, respectively) that can potentially confer resistance to tetracyclines and the macrolide-lincosamide streptogramin B group were identified. Theoretically, these AMR genes can impact the effectiveness of antibiotics commonly used in the treatment of STIs and BV. This study is the first to provide insight into the cervicovaginal microbiome and its resistome in Afro-Caribbean women

Intestinal and hepatic microbiota changes associated with chronic ethanol administration in mice

Alcohol-induced liver disease is closely related to translocation of bacterial products and bacteria from the intestine to the liver. However, it is not known whether bacterial translocation to the liver depends on certain intestinal microbiota changes that would predispose bacteria to translocate to the liver. In this study, we investigated the microbiota in the jejunum, ileum, cecum, feces and liver of mice subjected to chronic ethanol feeding using a Lieber DeCarli diet model of chronic ethanol feeding for 8 weeks. We demonstrate that chronic ethanol administration changes alpha diversity in the ileum and the liver and leads to compositional changes especially in the ileum. This is largely driven by an increase in gram-negative phyla - the source of endotoxins. Moreover, gram-negative Prevotella not only increased in the mucus layer of the ileum but also in liver samples. These results suggest that bacterial translocation to the liver might be associated with microbiota changes in the distal gastrointestinal tract

Longitudinal Study of Oral Microbiome Variation in Twins

Humans are host to a multitude of microorganisms that rapidly populate the body at birth, subject to a complex interplay that is dependent on host genetics, lifestyle, and environment. The host-associated microbiome, including the oral microbiome, presents itself in a complex ecosystem important to health and disease. As the most common chronic disease globally, dental caries is induced by host-microbial dysbiosis in children and adults. Multiple biological and environmental factors are likely to impact disease predisposition, onset, progression, and severity, yet longitudinal studies able to capture these influences are missing. To investigate how host genetics and environment influenced the oral microbial communities over time, we profiled supragingival plaque microbiomes of dizygotic and monozygotic twins during 3 visits over 12-months. Dental plaque DNA samples were amplified by targeting the 16S rRNA gene V4 region, and microbial findings were correlated with clinical, diet and genetic metadata. We observed that the oral microbiome variances were shaped primarily by the environment when compared to host genetics. Among the environmental factors shaping microbial changes of our subjects, significant metadata included age of the subject, and the age by which subjects initiated brushing habits, and the types of actions post-brushing. Relevant heritability of the microbiome included Actinomyces and Capnocytophaga in monozygotic twins and Kingella in dizygotic twins. Corynebacterium and Veillonella abundances were associated with age, whereas Aggregatibacter was associated with younger subjects. Streptococcus abundance showed an inverse association over time, and Selenomonas abundances increased with brushing frequency per day. Unraveling the exact biological mechanisms in caries has the potential to reveal novel host-microbial biomarkers, pathways, and targets important to effective preventive measures, and early disease control in children

Intestinal Fungal Dysbiosis and Systemic Immune Response to Fungi in Patients With Alcoholic Hepatitis.

Chronic alcohol consumption causes increased intestinal permeability and changes in the intestinal microbiota composition, which contribute to the development and progression of alcohol-related liver disease. In this setting, little is known about commensal fungi in the gut. We studied the intestinal mycobiota in a cohort of patients with alcoholic hepatitis, patients with alcohol use disorder, and nonalcoholic controls using fungal-specific internal transcribed spacer amplicon sequencing of fecal samples. We further measured serum anti-Saccharomyces cerevisiae antibodies (ASCA) as a systemic immune response to fungal products or fungi. Candida was the most abundant genus in the fecal mycobiota of the two alcohol groups, whereas genus Penicillium dominated the mycobiome of nonalcoholic controls. We observed a lower diversity in the alcohol groups compared with controls. Antibiotic or steroid treatment was not associated with a lower diversity. Patients with alcoholic hepatitis had significantly higher ASCA levels compared to patients with alcohol use disorder and to nonalcoholic controls. Within the alcoholic hepatitis cohort, patients with levels of at least 34 IU/mL had a significantly lower 90-day survival (59%) compared with those with ASCA levels less than 34 IU/mL (80%) with an adjusted hazard ratio of 3.13 (95% CI, 1.11-8.82; P = 0.031). Conclusion: Patients with alcohol-associated liver disease have a lower fungal diversity with an overgrowth of Candida compared with controls. Higher serum ASCA was associated with increased mortality in patients with alcoholic hepatitis. Intestinal fungi may serve as a therapeutic target to improve survival, and ASCA may be useful to predict the outcome in patients with alcoholic hepatitis