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The spleen is an immune organ that plays a key role in blood-borne immune responses. The anatomical or functional loss of this tissue increases susceptibility to severe blood infections and sepsis. Auto-transplantation of spleen slices has been used clinically to replace lost tissue and restore immune function. However, the mechanism driving robust and immunologically functional spleen tissue regeneration has not been fully elucidated. Here, we aim to develop a method for aggregating and encapsulating spleen cells within a semi-solid matrix in order to investigate the cellular requirements for spleen tissue formation. Basement membrane matrix encapsulated cell constructs are amenable to both in vitro tissue culture of three-dimensional organoids as well as transplantation under the kidney capsule to directly assess in vivo tissue formation. By manipulating the input cells for aggregation and encapsulation, we demonstrate that graft-derived PDGFRβ + MAdCAM-1 - neonatal stromal cells are required for spleen tissue regeneration under animal transplantation models.

Radiation-induced cystitis is an inflammatory condition affecting the urinary bladder, which can develop as a side effect of abdominopelvic radiotherapy, specifically external-beam radiation therapy or myeloablative radiotherapy. A possible involvement of mast cells in the pathophysiology of radiation-induced cystitis has been indicated in cases of external-beam radiation therapy; however, there is no evidence that these findings apply to the myeloablative aetiology. As such, this study investigated potential changes to urinary bladder mast cell prevalence when exposed to myeloablative radiation. Lethally irradiated C57BL/6J mice that received donor rescue bone marrow cells exhibited an increased mast cell frequency amongst host leukocytes 1 week following irradiation. By 4 weeks, no significant difference in either frequency or cell density was observed. However mast cell diameter was smaller, and a significant increase in mast cell number in the adventitia was observed. This study highlights that mast cells constitute a significant portion of the remaining host leukocyte population following radiation exposure, with changes to mast cell distribution and decreased cell diameter four weeks following radiation-induced injury., (© 2024. The Author(s).)

Objective: There are well-described impacts of biological rhythms on human physiology. With the increasing push for routine blood tests for preventative medical care and clinical and physiological research, optimizing effectiveness is paramount. This study aimed to determine whether it is feasible to assess diurnal variations of peripheral lymphocyte prevalence using finger prick blood in a small sample size., Methods: Using polychromatic flow cytometry, the prevalence of lymphocytes was assessed using 25 µL fingertip blood samples at 8 AM and 5 PM from 8 participants., Results: TH cells and B cells showed significantly higher percentages in the 5 PM samples, whereas NK cells demonstrated a significantly higher morning percentage. T cells, leukocytes, and cytotoxic T cells showed no significant changes., Conclusion: The detection of diurnal variations demonstrates that small blood volumes can be used to detect lymphocyte variations. The lower blood volume required provides a new testing method for clinical and research settings., (© The Author(s) 2023. Published by Oxford University Press on behalf of American Society for Clinical Pathology.)

Background: Mast cells have been implicated in the pathology of various urinary bladder disorders. However, the distribution of mast cells throughout urinary bladder tissue remains uncertain despite mast cell prevalence being relatively well-defined. Using a mouse tissue model, this study aims to characterise the prevalence and distribution of mast cells throughout the urinary bladder., Methods: Bladder tissues were collected from six C57BL/6J female mice. Mast cell prevalence was quantified by flow cytometry, based on the expression of the following characteristic markers: CD45, CD117 and FcɛRIα. The toluidine blue stain assessed mast cell distribution, size, and proximity to vasculature. A repeated measures one-way ANOVA was used to evaluate the density of mast cells between the discrete layers of the urinary bladder, and an ordinary one-way ANOVA was used to assess potential differences between mast cell size across the urinary bladder wall., Results: It was determined that mast cells compose less than 4% of all live leukocytes in the urinary bladder. They were also found to be more prominent in the lamina propria and detrusor muscle layers, compared to the urothelium and adventitia. In addition, 20.89% of mast cells were located near vasculature, which may be an important factor in consideration of their function and potential to contribute to various bladder pathologies, such as cystitis or overactive bladder., Conclusion: These findings provide a baseline understanding of mast cell prevalence and distribution throughout the urinary bladder., (© 2024. The Author(s).)

Background: Surgical high dependency (SHD) allows for intermediate care provision between general ward (GW) and intensive care unit (ICU) for surgical patients but no universally accepted admission criteria exists. Unnecessary SHD admissions should be minimized to limit resource wastage and maintain spare critical care capacity. This study evaluates the utility of SHD admissions following elective laparoscopic colectomy by comparing post-operative outcomes and interventions performed between SHD and GW patients., Methodology: A retrospective review of all colorectal cancer patients who underwent elective laparoscopic colectomy in our institution between January 2019 and December 2021 was conducted. Patients converted to open surgery or admitted to IC post-operatively were excluded. Peri-operative parameters and outcomes between patients admitted to GW and SHD post-operatively were evaluated., Results: The cohort comprised 393 patients. There were 153 patients (38.93%) who required SHD admission. SHD patients had higher American Society of Anesthesiology (ASA) scores, body mass index, age and intra-operative blood loss. Majority of post-operative morbidity were minor (Clavien-Dindo II or lower) in both groups and the interventions required were safely instituted in both SHD and GW. None of the patients in the cohort required inotropic or ventilatory support in the SHD., Conclusions: GW patients were "healthier" but post-operative morbidity and interventions required were similar to the SHD group. Nonetheless, treatment delays, absence of continuous monitoring, and decreased nurse-to-patient ratio may be significant for patients with limited physiological reserves. Further studies should evaluate safety and cost-effectiveness of managing high risk surgical patients in GW using continuous remote vital signs monitoring., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Despite the global prevalence of colorectal cancer (CRC) and efforts in screening advocacy, screening uptake remains relatively low. Considering the greater accessibility and popularity of telemedicine in behaviour change interventions, this meta-analysis seeks to examine the usefulness of digital interventions in promoting CRC screening uptake as compared to existing non-digital strategies. A systematic search on five databases identified articles published before September 2022. Randomized controlled trials comparing the effectiveness of digital interventions to usual care were included and assessed using the Cochrane's Risk of Bias tool. Effectiveness of interventions was measured by CRC screening completion rates, and pooled effect sizes were computed for both digital intervention subtypes identified - decision-making aids and tailored educational interventions. 14 studies (17,075 participants) assessed to have low or some risk of bias were included in this meta-analysis. A random-effects model revealed that digital interventions were more likely to promote CRC screening uptake (OR = 1.31, 95% CI: 1.11-1.56), and using a decision-making aid was almost 1.5 times more likely to result in screening completion (i.e., completed a colorectal investigation using stool-based or direct visualization test) (OR = 1.42, 95% CI: 1.24-1.63). Meanwhile, the tailored educational intervention subtype failed to achieve statistical significance in promoting screening uptake, bearing in mind the significant heterogeneity across studies (I 2  = 88.6%). Digital decision-making aids significantly improved CRC screening uptake compared to tailored digital educational interventions and usual care. However, as all included studies were conducted in Western settings, its role in augmenting existing CRC screening promotion strategies especially among Asians should be further evaluated., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Inc.)

Background: Enhanced recovery after surgery programs have improved patient outcomes following colorectal surgery. This has provided a platform for the consideration of ambulatory colectomies where patients are discharged within 24 hours after surgery. Although some studies have demonstrated its feasibility, the safety profile and patient eligibility criteria for discharge within 24 hours after surgery remain relatively ill-defined. This study provided a review of the patient selection criteria and postoperative outcomes shown in patients discharged within 24 hours after surgery., Methods: Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews guidelines were adhered to. A comprehensive search was performed on 3 electronic databases, and the relevant articles were identified. The primary outcome measures were postoperative morbidity and readmission rates. The different domains relevant to the selection of patients and perioperative care of patients discharged within 24 hours after surgery were also qualitatively assessed., Results: Eight studies were included, which involved a total of 1,229 patients. The majority of selected patients underwent elective laparoscopic colonic surgeries. The patient characteristics, such as age, comorbidities, obesity, and psychosocial environment, were important considerations. A close follow-up with home-based medical services was ideal in patients discharged within 24 hours after surgery. The readmission rates ranged from 0.0% to 9.0%. Despite morbidity rates of up to 26.7%, the majority of them were minor and classified as Clavien-Dindo Grade I to II., Conclusion: The use of programs related to discharge within 24 hours after surgery in colorectal surgery is safe, feasible, and practical in a select group of patients within a well-designed clinical framework and pathway. Future studies should compare patient outcomes following discharge within 24 hours after surgery with conventional enhanced recovery after surgery protocols. In addition, patient and caregiver perceptions, quality of life, and cost-effectiveness analysis should also be performed., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: The application of intra-operative blood salvage autotransfusion(IBSA) in liver transplantation(LT) for hepatocellular carcinoma(HCC) remains controversial due to the theoretical risk of tumour cell(TC) reintroduction. Current studies evaluating for presence of TC are limited by suboptimal detection techniques. This study aims to analyze the presence of TC in HCC LT autologous blood using microfluidics technology., Methods: A prospective study of HCC patients who underwent LT from February 2018-April 2019 was conducted. Blood samples were collected peri-operatively. TCs were isolated using microfluidics technology and stained with antibody cocktails for confirmation., Results: A total of 15 HCC LT patients were recruited. All recipients had tumour characteristics within the University of California, San Francisco(UCSF) criteria pre-operatively. TC was detected in all of the autologous blood samples collected from the surgical field. After IOCS wash, five patients had no detectable TC, while 10 patients had detectable TC; of these two remained positive for TC after Leukocyte Depletion Filter(LDF) filtration., Conclusion: The risk of tumour cell reintroduction using IBSA in HCC LT patients can be reduced with a single LDF. Future studies should evaluate the proliferation capacity and tumorigenicity of HCC TC in IBSA samples, and the effects of TC reintroduction in patients with pre-existing HCC TCs., (Copyright © 2021. Published by Elsevier Ltd.)

Introduction: Enhanced recovery after surgery (ERAS) programs for patients undergoing colorectal surgery has yielded promising results. However, there remains controversy regarding the application of ERAS protocols in an elderly population. The aim of this review is to compare the clinical outcomes between ERAS versus conventional peri-operative care (Non-ERAS) for colorectal surgery in patients aged ≥ 65 years old., Methods: The PRISMA guidelines were adhered to. A comprehensive search was performed using Medline, Embase and the Cochrane Library electronic databases and relevant articles were identified. Indications for the colorectal resections included both benign and malignant diseases, while emergency surgeries were excluded. Primary outcomes include post-operative morbidity, length of stay and re-admission rates. Data analysis was performed using Revman 5.3., Results: A total of six studies were included, which involved a total of 1174 patients. ERAS was associated with a lower incidence of post-operative morbidity compared to Non-ERAS (OR 0.38, 95% CI 0.25-0.59), p < 0.001). Similarly, ERAS was also associated with a significantly shorter hospital length of stay (MD - 2.49, 95% CI - 4.11 to 0.88, p = 0.002). Return of bowel function as measured by time to flatus was significantly faster in the ERAS group (MD - 20.01 95% CI - 36.23 to 3.79, p = 0.02), but post-operative ileus rates (OR 0.86, 95% CI 0.50-1.47, p = 0.58) were comparable. Re-admission, re-operation and post-operative mortality rates were also similar between both groups., Conclusion: The application of ERAS protocols in an elderly population provides the advantages of lower post-operative morbidity and shorter hospital length of stay. Future studies should aim to evaluate factors that can improve ERAS compliance rates in this group of patients.

Background: A longitudinal or a transverse incision is routinely used for common femoral artery (CFA) exposure. Some believe a transverse incision is associated with a lower incidence of postoperative complications. We performed a systematic review and meta-analysis to evaluate the risk of postoperative surgical site infection, lymphatic complications, wound dehiscence and haematoma formation when using a longitudinal or transverse incision for CFA exposure., Methods: Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines were adhered to. We searched various databases such as MEDLINE via PubMed and Embase for relevant studies from inception till 31 May 2020. Relevant search terms such as 'longitudinal', 'transverse', 'vertical', 'horizontal', 'femoral', 'incision' were used. We included both randomized controlled trials and case-controlled studies, and extracted data related to study characteristics and postoperative complications. We assessed risk of bias using the Cochrane risk of bias tool and the Newcastle-Ottawa scale. A random-effects meta-analysis was performed to obtain the pooled proportions and risk ratios (RR) for our study outcomes., Results: We included seven studies with a total of 5922 groin incisions. A longitudinal incision was associated with a significantly higher incidence of wound infection (RR 2.93, 95% confidence interval (CI) 1.12-7.70, P = 0.03) and wound dehiscence (RR 2.87, 95% CI 1.06-7.77, P = 0.04). The risk of lymphatic complications (RR 1.09, 95% CI 0.39-3.05, P = 0.87) and wound haematoma (RR 2.85, 95% CI 0.88-9.21, P = 0.08) were similar., Conclusions: A longitudinal incision may be associated with a higher incidence of wound infection and wound dehiscence, as compared to using a transverse incision for CFA exposure., (© 2020 Royal Australasian College of Surgeons.)

A reduction in daily caloric or nutrient intake has been observed to promote health benefits in mammals and other vertebrates. Feed Restriction (FR), whereby the overall food intake of the organism is reduced, has been explored as a method to improve metabolic and immune health, as well as to optimize productivity in farming. However, less is known regarding the molecular and physiological consequences of FR. Using the model organism, Danio rerio , we investigated the impact of a short-term (month-long) FR on growth, gut morphology and gene expression. Our data suggest that FR has minimal effects on the average growth rates, but it may affect weight and size heterogeneity in a sex-dependent manner. In the gut, we observed a significant reduction in gut circumference and generally lower mucosal heights, whereas other parameters remained unchanged. Gene Ontology (GO), EuKaryotic Orthologous Groups (KOG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified numerous metabolic, reproductive, and immune response pathways that were affected by FR. These results broaden our understanding of FR and contribute towards growing knowledge of its effects on vertebrate health.

Introduction: Elderly patients with colorectal cancer are high-risk surgical candidates. ERAS protocols have been developed to mitigate against these risks. We performed this study to quantify the risks which elderly patients face and then to determine independent risk factors for short-term ERAS-specific outcomes., Methods: An analysis of a prospectively collected audit database of all patients who underwent elective colorectal cancer resection within an ERAS framework from January 2018 to December 2018 was performed. Elderly was defined in our study as age ≥ 65 years., Results: There were 172 elective colorectal cancer resections performed. Ninety-seven (56.4%) were elderly. Elderly patients were at increased risk of developing post-operative complications (33.0% vs 16.0%, p = 0.011), longer time to diet (3.4 vs 2.2 days, p = 0.001), and longer hospital stay (10.9 vs 6.7 days, p = 0.007). Independent risk factors were determined for the abovementioned three outcomes. Elderly status was the only risk factor for increased complications (OR 2.61 95% CI (1.05-6.51), p = 0.040). For delayed time to soft diet, male gender (OR 6.67(1.92-20.0), p = 0.002), open approach (OR 9.06(2.26-36.30), p = 0.002), and increased operative time (OR 1.01(1.00-1.01) p = 0.014) were risk factors. Finally, elderly age (OR 5.53(1.82-16.84), p = 0.003), leucocyte count (OR 1.39(0.76-2.57), p = 0.038), open approach (OR 5.26(1.41-19.62), p = 0.013), operative time (OR 1.01(1.00-1.01), p = 0.021), and Clavien-Dindo classification (OR 7.97(1.27-49.88), p = 0.027) were risk factors for prolonged length of stay., Conclusion: Elderly patients are intrinsically at risk for increased complications, longer time to soft diet and longer hospital stay. ERAS protocols may need to be specifically tailored for elderly patients.

Spleen stromal lines which support in vitro hematopoiesis are investigated for their lineage origin and hematopoietic support function in vivo. Marker expression and gene profiling identify a lineage relationship with mesenchymal stem cells and perivascular reticular cells described recently in bone marrow. Stromal lines commonly express Cxcl12, Pdgfra and Pdgfr typical of bone marrow derived perivascular reticular cells but reflect a unique cell type in terms of other gene and marker expression. Their classification as osteoprogenitors is confirmed through ability to undergo osteogenic, but not adipogenic or chondrogenic differentiation. Some stromal lines were shown to form ectopic niches for HSCs following engraftment under the kidney capsule of NOD/SCID mice. The presence of myeloid cells and a higher representation of a specific dendritic-like cell type over other myeloid cells within grafts was consistent with previous in vitro evidence of hematopoietic support capacity. These studies reinforce the role of perivascular/perisinusoidal reticular cells in hematopoiesis and implicate such cells as niches for hematopoiesis in spleen., Competing Interests: The authors have declared that no competing interests exist.

Background: Minimally invasive pancreaticoduodenectomy (PD) is a feasible option for periampullary tumours. However, it remains a complex procedure with no proven advantages over open PD (OPD). The aim of the study was to compare the outcomes between laparoscopic-assisted PD (LAPD) and OPD using a propensity score-matched analysis., Methods: Retrospective review of 40 patients who underwent PD for periampullary tumours between January 2014 and December 2016 was conducted. The patients were matched 1:1 for age, gender, body mass index, Charlson comorbidty index, tumour size and haematological indices. Peri-operative outcomes were evaluated., Results: LAPD appeared to have a longer median operative time as compared to OPD (LAPD, 425 min (285-597) versus OPD, 369 min (260-500)) (P = 0.066). Intra-operative blood loss was comparable between both groups. Respiratory complications were five times higher in the OPD group (LAPD, 5% versus OPD, 25%) (P = 0.077), while LAPD patients required less time to start ambulating post-operatively (LAPD, 2 days versus OPD, 2 days) (P = 0.021). Pancreas-specific complications and morbidity/mortality rates were similar., Conclusion: LAPD is a safe alternative to OPD in a select group of patients for an institution starting out with minimally invasive PD, and can be used to bridge the learning curve required for total laparoscopic PD., (© 2019 Royal Australasian College of Surgeons.)

Background: To compare the presentations and outcomes of anti-HBc seropositive Hepatocellular Carcinoma (HBc-HCC) with anti-HBc seronegative (NHBc-HCC) patients in HBsAg negative Non-HBV Non-HCV (NBNC-HCC) HCC population., Methods: 515 newly diagnosed HCC patients from January 2011 to September 2016 were retrospectively reviewed. 145 (66.5%) NHBc-HCC and 73 (33.5%) HBc-HCC patients were identified. Patient demographics, disease characteristics, details of treatments, recurrence and survival outcomes were analysed., Results: A significantly lower proportion of HBc-HCC patients were diagnosed through surveillence (6.8% vs 26.2%, p = 0.001). HBc-HCC patients were less likely cirrhotic (p < 0.001), portal hypertensive (p < 0.001), ascitic (p = 0.008) and thrombocytopenic (p = 0.003). A higher proportion of HBc-HCC patients had treatment with curative intent (46.6% vs 30.3%, p = 0.018) and surgery (39.7% vs 16.6%, p < 0.001). Although HBc-HCC patients had larger median tumor size (74.0 mm vs 55.0 mm, p = 0.016) with a greater proportion of patients having tumors ≥5 cm, there was no difference in the overall median survival (19.0 months vs 22.0 months, p = 0.919) and recurrence rates (38.2% vs 40.9%)., Conclusion: Isolated anti-HBc seropositivity in HbsAg negative patients tend to present incidentally with delayed diagnoses resulting in larger tumors, but their long-term survival remain comparable., (Copyright © 2018 International Hepato-Pancreato-Biliary Association Inc. Published by Elsevier Ltd. All rights reserved.)

The spleen is an organ that filters the blood and is responsible for generating blood-borne immune responses. It is also an organ with a remarkable capacity to regenerate. Techniques for splenic auto-transplantation have emerged to take advantage of this characteristic and rebuild spleen tissue in individuals undergoing splenectomy. While this procedure has been performed for decades, the underlying mechanisms controlling spleen regeneration have remained elusive. Insights into secondary lymphoid organogenesis and the roles of stromal organiser cells and lymphotoxin signalling in lymph node development have helped reveal similar requirements for spleen regeneration. These factors are now considered in the regulation of embryonic and postnatal spleen formation, and in the establishment of mature white pulp and marginal zone compartments which are essential for spleen-mediated immunity. A greater understanding of the cellular and molecular mechanisms which control spleen development will assist in the design of more precise and efficient tissue grafting methods for spleen regeneration on demand. Regeneration of organs which harbour functional white pulp tissue will also offer novel opportunities for effective immunotherapy against cancer as well as infectious diseases., Competing Interests: The authors declare no competing financial interests.

Introduction: Studies have shown that same-admission laparoscopic cholecystectomy (SALC) is superior to delayed laparoscopic cholecystectomy (DLC) for acute cholecystitis (AC). However, no studies have compared both modalities in patients with delayed presentation. The aim of the study was to compare outcomes between SALC and DLC in AC patients with more than 7-day symptom duration., Methods: A retrospective analysis of 83 AC patients who underwent LC after presenting with >7 days of symptoms from June 2010 to June 2015 was performed. Patients were divided into L-SALC and L-DLC, defined as LC performed within the same admission and between 4 and 24 weeks after discharge, respectively. Peri-operative outcomes were evaluated., Results: In L-SALC patients, the intra-operative severity was higher (p < 0.001) and median operative time was longer (L-SALC, 107 min (46-220) vs L-DLC, 95 mins (25-186)) (p = 0.048). Conversion rates were also higher in L-SALC than that in L-DLC (L-SALC, 21.4% vs L-DLC, 4.9%) (p = 0.048). While post-operative morbidity was similar, L-SALC was associated with a longer post-operative length of stay as compared to L-DLC (L-SALC, 2 (1-17) vs L-DLC, 1 (1-6)) (p < 0.001)., Conclusion: DLC provides lower conversion rates and shorter length of stay in AC patients presenting beyond 7 days of symptoms. This group of patients should be offered DLC.