Genomics-Microbiome Based Assessment of Bidirectional Causality Between Gut Microbiota and Psoriasis.

Background: Traditional observational studies have found a possible risk association of the gut microbiota for psoriasis. Meanwhile, psoriasis may also affect the changes in the gut microbiota. However, the available evidence does not demonstrate a reciprocal relationship between the gut microbiota and psoriasis. This limits our understanding on the role of the gut microbiota in the mechanisms of psoriasis. Methods: To address this question we used Mendelian randomization, a novel epidemiological approach, and acquired the largest current gut microbiota GWAS data from the MiBioGen consortium as well as psoriasis GWAS data from the FinnGen consortium, and performed two-sample bidirectional MR analyses using a multiple MR analysis approach. Finally, the robustness of the results was assessed by sensitivity analysis. Results: Our results indicate that five bacterial genera are causally related to psoriasis and psoriasis is causally related to four bacterial genera. Conclusion: These results suggest a bidirectional causal influence of psoriasis on the gut microbiota. Our results somewhat challenge the causal inferences of previous observational studies. We found that the specific bacterial genera with a risk effect on psoriasis were different from those found to characterize psoriasis in previous observational studies, and that these psoriasis-characterizing genera were inversely associated with psoriasis.

Construct Validity of a Novel Assessment System for Laparoscopic Suture Accuracy Based on Stereoscopy.

BACKGROUND: An accurate and objective measuring tool is lacking for laparoscopic suture accuracy assessment in simulation training. We designed and developed the suture accuracy testing system (SATS) and aimed to determine its construct validity in this study. METHODS: Twenty laparoscopic experts and 20 novices were recruited to perform a suturing task in three sessions using traditional laparoscopic instruments (Tra. session), a handheld multi-degree-of-freedom (MDoF) laparoscopic instrument (MDoF session) and a surgical robot (Rob. session), respectively. The needle entry and exit errors were calculated using the SATS and compared between the two groups. RESULTS: No significant difference of the needle entry error was found in all comparisons. As for the needle exit error, the value of the novice group was significantly higher than that of the expert group in Tra. session (3.48 ± 0.61 mm vs. 0.85 ± 0.14 mm; p = 1.451e-11) and MDoF session (2.65 ± 0.41 mm vs. 1.06 ± 0.17 mm; p = 1.451e-11) but not in Rob. session (0.51 ± 0.12 mm vs. 0.45 ± 0.08 mm; p = 0.091). CONCLUSIONS: The SATS demonstrates construct validity. Surgeons' experience in conventional laparoscopic instruments could be transferred to the MDoF instrument. Surgical robot helps to improve suture accuracy and may bridge the experience gap between laparoscopic experts and novices in basic exercises.

3D reconstruction based novel methods are more effective than traditional clinical assessment in breast cancer axillary lymph node metastasis prediction.

The status of axillary lymph node metastases determines the treatment and overall survival of breast cancer (BC) patients. Three-dimensional (3D) assessment methods have advantages for spatial localization and are more responsive to morphological changes in lymph nodes than two-dimensional (2D) assessment methods, and we speculate that methods developed using 3D reconstruction systems have high diagnostic efficacy. This exploratory study included 43 patients with histologically confirmed BC diagnosed at Second Xiangya Hospital of Central South University between July 2017 and August 2020, all of whom underwent preoperative CT scans. Patients were divided into a training cohort to train the model and a validation cohort to validate the model. A 3D axillary lymph node atlas was constructed on a 3D reconstruction system to create various methods of assessing lymph node metastases for a comparison of diagnostic efficacy. Receiver operating characteristic (ROC) curve analysis was performed to assess the diagnostic values of these methods. A total of 43 patients (mean [SD] age, 47 [10] years) met the eligibility criteria and completed 3D reconstruction. An axillary lymph node atlas was established, and a correlation between lymph node sphericity and lymph node metastasis was revealed. By continuously fitting the size and characteristics of axillary lymph nodes on the 3D reconstruction system, formulas and models were established to determine the presence or absence of lymph node metastasis, and the 3D method had better sensitivity for axillary lymph node assessment than the 2D method, with a statistically significant difference in the correct classification rate. The combined diagnostic method was superior to a single diagnostic method, with a 92.3% correct classification rate for the 3D method combined with ultrasound. In addition, in patients who received neoadjuvant chemotherapy (NAC), the correct classification rate of the 3D method (72.7%) was significantly higher than that of ultrasound (45.5%) and CT (54.5%). By establishing an axillary lymph node atlas, the sphericity formula and model developed with the 3D reconstruction system achieve a high correct classification rate when combined with ultrasound or CT and can also be applied to patients receiving NAC.

Assessment of occupant-behavior-based indoor air quality and its impacts on human exposure risk: A case study based on the wildfires in Northern California.

The recent wildfires in California, U.S., have caused not only significant losses to human life and property, but also serious environmental and health issues. Ambient air pollution from combustion during the fires could increase indoor exposure risks to toxic gases and particles, further exacerbating respiratory conditions. This work aims at addressing existing knowledge gaps in understanding how indoor air quality is affected by outdoor air pollutants during wildfires-by taking into account occupant behaviors (e.g., movement, operation of windows and air-conditioning) which strongly influence building performance and occupant comfort. A novel modeling framework was developed to simulate the indoor exposure risks considering the impact of occupant behaviors by integrating building energy and occupant behaviour modeling with computational fluid dynamics simulation. Occupant behaviors were found to exert significant impacts on indoor air flow patterns and pollutant concentrations, based on which, certain behaviors are recommended during wildfires. Further, the actual respiratory injury level under such outdoor conditions was predicted. The modeling framework and the findings enable a deeper understanding of the actual health impacts of wildfires, as well as informing strategies for mitigating occupant health risk during wildfires.

Assessment of therapeutic efficacy of liposomal nanoparticles mediated gene delivery by molecular imaging for cancer therapy.

The inadequate treatment efficacy, suboptimal cancer detection and disease monitoring in anticancer therapies have led to the quest for clinically relevant, innovative multifaceted solutions such as development of targeted and traceable approaches. Molecular imaging technologies with the versatility of liposomal nanoparticles platform offer tangible options to better guide treatment delivery and monitor outcome. In this study, we introduced noninvasive, quantitative and functional imaging techniques with reporter gene methods to probe breast cancer processes with liposomal nanoparticles by bioluminescence imaging (BLI). A breast cancer model was applied for therapy by injecting 5.0 x 10(5) 4T1 cells carrying a reporter system encoding a double fusion reporter gene consisting of firefly luciferase (Fluc) and green fluorescent protein (GFP) into BALB/c mice. Liposomal nanoparticles loaded with a triple fusion gene containing the herpes simplex virus truncated thymidine kinase (HSV-ttk) and renilla luciferase (Rluc) and red fluorescent protein (RFP) were applied by in situ injection for monitoring and evaluating gene therapy. The BALB/c mice were subsequently treated with ganciclovir (GCV) and the growth status of tumor was monitored by bioluminescence imaging of Fluc and the treatment delivery of liposomal nanoparticle was efficiently tracked by Rluc imaging. In fact, TF plasmids were shown to be useful for monitoring and evaluating targeting efficacy and gene therapy by non-invasive molecular imaging. In conclusion, the combination of noninvasive imaging techniques and liposomal nanoparticle can provide a practical and clinically useful way for gene delivery and monitoring the level of gene expression over time and treatment response in patients undergoing gene therapy.

Neuropeptide Y and agouti-related peptide mediate complementary functions of hyperphagia and reduced energy expenditure in leptin receptor deficiency.

Neuropeptide Y (NPY) and agouti-related peptide (AGRP) can produce hyperphagia, reduce energy expenditure, and promote triglyceride deposition in adipose depots. As these two neuropeptides are coexpressed within the hypothalamic arcuate nucleus and mediate a major portion of the obesity caused by leptin signaling deficiency, we sought to determine whether the two neuropeptides mediated identical or complementary actions. Because of separate neuropeptide receptors and signal transduction mechanisms, there is a possibility of distinct encoding systems for the feeding and energy expenditure aspects of leptin-regulated metabolism. We have genetically added NPY deficiency and/or AGRP deficiency to LEPR deficiency isolated to AGRP cells. Our results indicate that the obesity of LEPR deficiency in AGRP/NPY neurons can produce obesity with either AGRP or NPY alone with AGRP producing hyperphagia while NPY promotes reduced energy expenditure. The absence of both NPY and AGRP prevents the development of obesity attributable to isolated LEPR deficiency in AGRP/NPY neurons. Operant behavioral testing indicated that there were no alterations in the reward for a food pellet from the AGRP-specific LEPR deficiency.