Citations

The patient is a male in his 60s with morbid obesity and end-stage renal disease secondary to hypertension and diabetes. After a lifelong struggle with weight management, he was approved for bariatric surgery. Following completion of the bariatric clinic courses, he underwent laparoscopic Roux-en-Y gastric bypass. There were no intraoperative complications nor divergences from our routine practice. Postoperatively, the patient resumed peritoneal dialysis (PD) on postoperative day zero. He tolerated the operation and dialysis well, noting that the drained abdominal fluid remained serosanguinous for 5 days after surgery. While the traditional practice after intra-abdominal surgery is to temporarily transition to haemodialysis in patients who require dialysis, we demonstrate that immediate resumption of PD may be safe and efficacious. However, patients should be educated regarding the temporary change in colour of the drained intra-abdominal fluid. More robust data is required for further research and future practice guideline development.

Study Design: Retrospective analyses of the center of rotation (COR) in asymptomatic volunteers and symptomatic patients. Objective: Document (i) level-specific COR position at radiographically normal levels in asymptomatic volunteers, (ii) preoperative COR abnormalities in symptomatic patients, and (iii) correlations between COR and other intervertebral motion metrics. Summary of Background Data: The COR has been discussed in many prior publications; however, our understanding of the normal position of the COR, the types and prevalence of COR abnormalities in patients, and the association between COR and other more common measures of intervertebral motion remains limited. Methods: Using automated, FDA-cleared software, we quantified COR and standard motion/alignment metrics from cervical flexion-extension radiographs of 341 asymptomatic volunteers and 1263 symptomatic preoperative patients. Level-specific 95% reference ellipses were derived from volunteers. Abnormality was defined as COR outside the level-matched ellipse. Associations between COR (cranial-caudal and anteroposterior) and rotation, translation, sagittal plane offset, disc height change, and standardized instability indices were evaluated. Results: In volunteers, COR was level-dependent and well summarized by 95% reference ellipses. The cranial-caudal position of COR was chiefly determined by rotation and translation, whereas the anteroposterior position related to sagittal plane offset and disc height change. COR also correlated with translational (TI-Index) and vertical (AVI/PVI) instability metrics. In symptomatic patients, most levels fell within reference ellipses; when deviations occurred, they were infrequent and multidirectional. Conclusions: COR can be automatically derived from flexion-extension radiographs. Deviations from level-specific reference ellipses provide an intuitive visualization of abnormal kinematics, complementing established motion metrics and linking cranial-caudal and anteroposterior shifts to specific patterns of translation, alignment, and instability.

Background: Tranexamic acid (TXA) is widely used in craniosynostosis surgery to reduce blood loss. Although the efficacy of TXA administration has been documented in the literature, dosing in the perioperative setting is variable and without a standard protocol. The purpose of this study is to determine the efficacy of continuing TXA postoperatively for patients undergoing suturectomy for metopic or unicoronal synostosis. Methods: We conducted a retrospective cohort study evaluating the use of postoperative TXA infusion in patients undergoing suturectomy for metopic and unicoronal craniosynostosis. All patients received a TXA bolus of 10 mg/kg at the time of surgical prep, followed by a TXA infusion at 5 mg/kg/hour during the procedure. Patients undergoing suturectomy for metopic or unicoronal synostosis in 2020 to 2021 received postoperative TXA infusion at 5 mg/kg/hour for the first 4 hours after surgery. Following a protocol change in anemia management at the institution in 2022, patients undergoing this surgery in 2022 did not receive a postoperative TXA infusion. Chart review was performed, and mean hemoglobin values were compared between patients who received postoperative TXA and those who did not, with analyses stratified by suture involvement to determine the impact of the protocol change. Results: Twenty-eight patients met the inclusion criteria: 14 patients received postoperative TXA, and 14 patients did not. Both groups included 8 patients undergoing metopic suturectomy and 6 patients undergoing unicoronal suturectomy. For patients who underwent metopic suturectomy and received postoperative TXA, the mean preoperative hemoglobin was 11.4 g/dL, and on postoperative day 1 (POD1) was 8.1 g/dL. For patients who underwent metopic suturectomy and did not receive postoperative TXA, the mean preoperative hemoglobin was 11 g/dL and on POD1 was 9.2 g/dL ( P =0.27). The differences in mean preoperative and postoperative hemoglobin were not statistically significant between the 2 cohorts, P =0.15 and P =0.20, respectively. For patients who underwent unicoronal suturectomy and received postoperative TXA, the mean preoperative hemoglobin was 12 g/dL, and on POD1 was 8.7 g/dL. For patients who underwent unicoronal suturectomy and did not receive postoperative TXA, the mean preoperative hemoglobin was 11.4 g/dL and on POD1 was 9.1 g/dL ( P =0.36). The mean preoperative and postoperative hemoglobin were not statistically different between the 2 cohorts, P =0.42 and P =0.92, respectively. Hospital length of stay averaged 1 day across both cohorts. No patient received a postoperative blood transfusion. Conclusion: In patients undergoing suturectomy for metopic or unicoronal craniosynostosis, postoperative TXA infusion made no significant difference in postoperative hemoglobin levels, length of stay, or postoperative transfusion. Discontinuing postoperative TXA could potentially decrease monitoring needs and lower hospital costs.

BACKGROUND: Subtotal cholecystectomy is increasingly recommended as a bailout strategy for the difficult gallbladder, yet its long-term durability and the risk profile of subsequent completion cholecystectomy remain incompletely defined. STUDY DESIGN: We performed a population-based retrospective cohort study of adults undergoing laparoscopic or open subtotal cholecystectomy for acute cholecystitis from 2012 to 2021 using Healthcare Cost and Utilization Project state databases from New York and Florida. The primary endpoint was remnant cholecystitis, defined as a postoperative emergency, inpatient, or outpatient diagnosis of cholecystitis or need for subsequent cholecystectomy. Kaplan–Meier analysis estimated cumulative incidence. Secondary outcomes included completion cholecystectomy and bile duct injury requiring surgical repair. RESULTS: Among 2,682 patients (98.7% laparoscopic), the cumulative incidence of remnant cholecystitis was 13.3% during a median follow-up of 2 years (interquartile range [IQR] 0.7 to 4.1). The median time to developing remnant cholecystitis was 28 days (IQR 13 to 91), with 79.7% occurring within 6 months. Only 70 patients (2.6%) underwent completion cholecystectomy at a median of 103 days (IQR 43 to 202). Completion cholecystectomy was performed via open surgery in 47.1% of patients and was associated with a 7.1% bile duct injury rate and median length of stay of 3 days (IQR 1 to 7), compared with a 0.9% bile duct injury rate for subtotal cholecystectomy overall. CONCLUSIONS: Although remnant cholecystitis occurred in 13.3% of patients after subtotal cholecystectomy, few required completion cholecystectomy. When necessary, completion cholecystectomy was frequently open and associated with a substantially higher bile duct injury rate, supporting referral to experienced hepatobiliary centers for reoperation.

Biological heterogeneity among different breast cancer (BC) subtypes results in markedly varying clinical outcomes. Identification and analysis of key gene biomarkers that are differentially regulated during radiation therapy (RT) may pose multiple clinical challenges for BC treatment. The purpose of the study is to identify and analyze the expression of key gene biomarkers and their networks that are differentially regulated after hypofractionated RT. Patients with BC (cT0-T2, N0, M0) were treated with hypofractionated whole breast RT 25 Gy in five fractions, 4 to 8 weeks before breast conservation surgery (BCS). Biopsy (pre-RT; n = 5) and surgical (post-RT; n = 14 or 15) BC tumor samples were used for NanoString targeted sequencing. We identified 165 and 244 differentially expressed genes (DEGs; p < 0.05) in BC tumor samples from BC patients post-RT using the nCounter BC360 and IO360 panels, respectively. Gene networks and pathway analysis revealed that RT increases the gene signature of tumor inflammation (TIS), cytotoxicity, and apoptosis, while downregulating the gene signatures of tumor cell proliferation, differentiation, and cell adhesion, and increases the claudin-low gene score. RT-induced mammary stemness and enhanced infiltration of stroma, mast, and macrophage cells in the BC tumor microenvironment (TME). Further, the nCounter IO360 (immuno-oncology) panel analysis validated the findings of BC360 and demonstrated that RT increased the myeloid inflammation signature and chemokine expression, modulated B, T, NK, and DC cell activities, and enhanced residual cancer burden (RCB) in BC tumors, thus creating an immunosuppressive TME. Collectively, RT sensitized BC tumors by increasing the gene signature of TIS, cytotoxicity, apoptosis, and mammary stemness. RT facilitated an immunosuppressive environment and increased RCB, suggesting that the therapeutic potential of RT is highly individualized for each patient based on their unique tumor biology, genetic makeup, and TME.

The regulation of the cardiomyocyte cell cycle is central to understanding heart regeneration. In adult mammals, cardiomyocytes withdraw from the cell cycle, limiting their ability to proliferate and repair heart tissue after injury. This process is controlled by intrinsic genetic programs and extrinsic signals, which together restrict the regenerative response in mature hearts. Understanding the mechanisms that regulate cardiomyocyte cell cycle activity is therefore critical for advancing cardiac regenerative medicine. In this review, we provide a comparative and integrated overview of cardiomyocyte cell cycle regulation in lower vertebrates and mammals, and discuss the major intrinsic factors that govern this process, including cyclin/CDK pathways, transcription factors and co-activators, oxygen and metabolic regulation, and epigenetic mechanisms. We also review the influence of hormones and growth factors, as well as the supportive roles of nonmyocyte populations in heart regeneration. By integrating findings across species, developmental stages, and regulatory levels, these findings highlight the complex regulatory network controlling cardiomyocyte proliferation and provide insight into potential therapeutic strategies for stimulating cardiac repair in the adult mammalian heart.

Abstract Introduction Detecting and estimating blood volume loss are important for the diagnosis and management of life-threatening hemorrhage. There is a direct relationship between percent blood volume loss (BVL%) and falling in stroke volume (SV); furthermore, there is a direct relationship between diminishing SV and the corrected flow time of the carotid artery (ccFT). Therefore, we hypothesized that change in ccFT (ccFTΔ) would directly relate with BVL% in a phlebotomy paradigm. Materials and Methods A prospective, convenience sample of healthy volunteers was studied. Volunteers underwent blood donation protocol in a physiology lab. A wireless, wearable Doppler ultrasound system monitored ccFT during blood donation. Traditional vital signs were also measured throughout. The relationship between traditional vital signs as well as ccFTΔ were compared to BVL% using 2 mixed linear regression models. Results Data from 20 subjects and blood donations comprising 46,123 cardiac cycles are included. On average 413.5 ± 39 mL of blood were drawn representing 8.6 ± 1.6% BVL%. There was a significant and strong linear relationship between BVL% and ccFTΔ during blood draw with the regression slope demonstrating that for every 1 ms reduction in ccFT there was a 0.4% reduction in blood volume. Conclusions In healthy subjects and when blood loss is the sole mechanism for falling SV, we estimate that for every 1 ms reduction in ccFT, there is an approximate 0.4 BVL%. Validation of these results in patients with traumatic hemorrhage is underway.

Abstract Objective Evaluate how RAG architecture, including corpus structure, retrieval strategy, and pipeline complexity, affects LLM-based medical problem solving and knowledge retrieval in sleep medicine. Materials and Methods We benchmarked four open-source LLMs (Llama-3-8B, Llama -3 -70B, Qwen 2.5-14B, and Qwen 2.5-235B) using a knowledge base of five sleep medicine textbooks. We compared performance across three dimensions: corpus structure (raw text vs table-of-contents aligned.), retrieval strategy (dense embedding vs hybrid sparse-dense), and pipeline complexity (baseline vs augmented). Evaluation metrics included board-style multiple choice question (MCQ) accuracy and clinical case vignette diagnostic ranking. Results RAG improved MCQ accuracy for all models. Llama-8B saw the largest gain of 10.6% (61.8% to 72.4%), while Qwen-235B reached 87.3%. In clinical cases, Llama-8B accuracy dropped by 7.1% when using raw text and dense retrieval due to context noise. This was corrected by using structured hybrid configurations. Hybrid retrieval consistently outperformed dense-only methods. Overall, structured corpora improved primary diagnosis accuracy by 6.1% on average, with Qwen-235B reaching a peak 10.2% increase. Discussion RAG effectiveness depends on the balance between model size and data structure. Large models handle uncurated text well, but smaller models are easily distracted by irrelevant data. Hybrid retrieval is necessary to maintain precision with specialized medical terms. A structured corpus paired with a baseline hybrid pipeline offers the best stability and speed for clinical use. Conclusion Rigorous data curation and hybrid retrieval are as essential as model scale for deploying safe, guideline-compliant AI in sleep medicine.