Clinical and functional outcomes of reverse total shoulder arthroplasty supplemented with latissimus dorsi transfer: a systematic review and meta-analysis.

Background: To optimize patients' functional external rotation outcomes, reverse total shoulder arthroplasties (rTSAs) including a latissimus dorsi tendon transfer were undertaken with promising early results and no significant increase in complications in comparison to traditional rTSAs. This was especially utilized for patients with a pronounced combined loss of elevation and external rotation. The purpose of this study is to evaluate and synthesize the findings of all relevant publications assessing the outcomes of rTSAs with associated latissimus dorsi transfer. Methods: We thoroughly searched the literature within the PubMed database using a standardized methodology. For our inclusion criteria, we included any study regarding rTSAs that contained functional outcome scores for postoperative range of motion (such as elevation, external rotation, etc.) or postoperative outcomes such as complications (reoperation, infection, etc.) and patient satisfaction. For the extraction of data, we used pilot-tested Google Forms to record extracted data. These data were then converted to spreadsheets (Microsoft Excel [Microsoft, Redmond, WA, USA]). This was done on 2 separate scenarios by 2 authors to ensure accuracy. We used the modified Coleman Methodology Score to assess the methodological quality of the studies in our samples. Meta-analysis mathematics and statistical analysis were performed using Stata software 17 (StataCorp, College Station, TX, USA). Results: Our search returned a total of 12 studies containing data of 213 shoulders receiving RTSAs with a latissimus dorsi transfer. Functional outcomes were available for 160 shoulders. The mean preoperative elevation of the affected shoulder was 73.57 degrees, and the mean postoperative elevation was 141.80 degrees. For external rotation, the mean preoperative average was -6.71 degrees, and the mean postoperative average was 22.73 degrees. The absolute Constant score average was 31.56 preoperatively, while the postoperative value was 68.93. In our sample, 25 patients (11.73%) required a revision of the RTSA implant due to complications. Discussion: Combined loss of elevation and external rotation can be a severely debilitating condition for those with a glenohumeral pathology. Latissimus dorsi transfer for this condition has been proven to be an effective modality. The reoperation and complication rate appears to be sizable, and as such surgeons should consider this when considering this modality for their patients.

Epithelial-myeloid exchange of MHC class II constrains immunity and microbiota composition.

Intestinal epithelial cells (IECs) have long been understood to express high levels of major histocompatibility complex class II (MHC class II) molecules but are not considered canonical antigen-presenting cells, and the impact of IEC-MHC class II signaling on gut homeostasis remains enigmatic. As IECs serve as the primary barrier between underlying host immune cells, we reasoned that IEC-intrinsic antigen presentation may play a role in responses toward the microbiota. Mice with an IEC-intrinsic deletion of MHC class II (IECΔMHC class II) are healthy but have fewer microbial-bound IgA, regulatory T cells (Tregs), and immune repertoire selection. This was associated with increased interindividual microbiota variation and altered proportions of two taxa in the ileum where MHC class II on IECs is highest. Intestinal mononuclear phagocytes (MNPs) have similar MHC class II transcription but less surface MHC class II and are capable of acquiring MHC class II from IECs. Thus, epithelial-myeloid interactions mediate development of adaptive responses to microbial antigens within the gastrointestinal tract.

Fusobacterium nucleatum and Clinicopathologic Features of Colorectal Cancer: Results From the ColoCare Study.

BACKGROUND: Fusobacterium nucleatum (Fn), a bacterium associated with a wide spectrum of infections, has emerged as a key microbe in colorectal carcinogenesis. However, the underlying mechanisms and clinical relevance of Fn in colorectal cancer (CRC) remain incompletely understood. PATIENTS AND METHODS: We examined associations between Fn abundance and clinicopathologic characteristics among 105 treatment-naïve CRC patients enrolled in the international, prospective ColoCare Study. Electronic medical charts, including pathological reports, were reviewed to document clinicopathologic features. Quantitative real-time polymerase chain reaction (PCR) was used to amplify/detect Fn DNA in preoperative fecal samples. Multinomial logistic regression was used to analyze associations between Fn abundance and patient sex, age, tumor stage, grade, site, microsatellite instability, body mass index (BMI), alcohol consumption, and smoking history. Cox proportional hazards models were used to investigate associations of Fn abundance with overall survival in adjusted models. RESULTS: Compared to patients with undetectable or low Fn abundance, patients with high Fn abundance (n = 22) were 3-fold more likely to be diagnosed with rectal versus colon cancer (odds ratio [OR] = 3.01; 95% confidence interval [CI], 1.06-8.57; P = .04) after adjustment for patient sex, age, BMI, and study site. Patients with high Fn abundance also had a 5-fold increased risk of being diagnosed with rectal cancer versus right-sided colon cancer (OR = 5.32; 95% CI, 1.23-22.98; P = .03). There was no statistically significant association between Fn abundance and overall survival. CONCLUSION: Our findings suggest that Fn abundance in fecal samples collected prior to surgery varies by tumor site among treatment-naïve CRC patients. Overall, fecal Fn abundance may have diagnostic and prognostic significance in the clinical management of CRC.

Expansion of Bacteriophages Is Linked to Aggravated Intestinal Inflammation and Colitis.

Bacteriophages are the most abundant members of the microbiota and have the potential to shape gut bacterial communities. Changes to bacteriophage composition are associated with disease, but how phages impact mammalian health remains unclear. We noted an induction of host immunity when experimentally treating bacterially driven cancer, leading us to test whether bacteriophages alter immune responses. Treating germ-free mice with bacteriophages leads to immune cell expansion in the gut. Lactobacillus, Escherichia, and Bacteroides bacteriophages and phage DNA stimulated IFN-γ via the nucleotide-sensing receptor TLR9. The resultant immune responses were both phage and bacteria specific. Additionally, increasing bacteriophage levels exacerbated colitis via TLR9 and IFN-γ. Similarly, ulcerative colitis (UC) patients responsive to fecal microbiota transplantation (FMT) have reduced phages compared to non-responders, and mucosal IFN-γ positively correlates with bacteriophage levels. Bacteriophages from active UC patients induced more IFN-γ compared to healthy individuals. Collectively, these results indicate that bacteriophages can alter mucosal immunity to impact mammalian health.