Relation between resting spleen volume and apnea-induced increases in hemoglobin mass.

Introduction: Indigenous populations renowned for apneic diving have comparatively large spleen volumes. It has been proposed that a larger spleen translates to heightened apnea-induced splenic contraction and elevations in circulating hemoglobin mass (Hbmass), which, in theory, improves O2 carrying and/or CO2/pH buffering capacities. However, the relation between resting spleen volume and apnea- induced increases in Hbmass is unknown. Therefore, we tested the hypothesis that resting spleen volume is positively related to apnea-induced increases in total Hbmass. Methods: Fourteen healthy adults (six women; 29 ± 5 years) completed a two-minute carbon monoxide rebreathe procedure to measure pre-apneas Hbmass and blood volume. Spleen length, width, and thickness were measured pre-and post-five maximal apneas via ultrasound. Spleen volume was calculated via the Pilström equation (test-retest CV:2 ± 2%). Hemoglobin concentration ([Hb]; g/dl) and hematocrit (%) were measured pre- and post-apneas via capillary blood samples. Post-apneas Hbmass was estimated as post-apnea [Hb] x pre-apnea blood volume. Data are presented as mean ± SD. Results: Spleen volume decreased from pre- (247 ± 95 mL) to post- (200 ± 82 mL, p<0.01) apneas. [Hb] (14.6 ± 1.2 vs. 14.9 ± 1.2 g/dL, p<0.01), hematocrit (44 ± 3 vs. 45 ± 3%, p=0.04), and Hbmass (1025 ± 322 vs. 1046 ± 339 g, p=0.03) increased from pre- to post-apneas. Pre-apneas spleen volume was unrelated to post-apneas increases in Hbmass (r=-0.02, p=0.47). O2 (+28 ± 31 mL, p<0.01) and CO2 (+31 ± 35 mL, p<0.01) carrying capacities increased post-apneas. Conclusion: Larger spleen volume is not associated with a greater rise in apneas-induced increases in Hbmass in non-apnea-trained healthy adults.

Blood defense system - Proposal for a new concept of an immune system against blood borne pathogens comprising the liver, spleen and bone marrow.

Blood-borne pathogen (BBP) infections can rapidly progress to life-threatening sepsis and must therefore be promptly eliminated by the host's immune system. Intravascular macrophages of the liver sinusoid, splenic marginal zone and red pulp and perisinusoidal macrophage protrusions in the bone marrow (BM) directly phagocytose BBPs in the blood as an innate immune response. The liver, spleen and BM thereby work together as the blood defence system (BDS) in response to BBPs by exerting their different immunological roles. The liver removes the vast majority of these invading organisms via innate immunity, but their complete elimination is not possible without the actions of antibodies. Splenic marginal zone B cells promptly produce IgM and IgG antibodies against BBPs. The splenic marginal zone transports antigenic information from the innate to the adaptive immune systems. The white pulp of the spleen functions as adaptive immune tissue and produces specific and high-affinity antibodies with an immune memory against BBPs. The BM works to maintain immune memory by supporting the survival of memory B cells, memory T cells and long-lived plasma cells (LLPCs), all of which have dedicated niches. Furthermore, BM perisinusoidal naïve follicular B cells promptly produce IgM antibodies against BBPs in the BM sinusoid and the IgG memory B cells residing in the BM rapidly transform to plasma cells which produce high-affinity IgG antibodies upon reinfection. This review describes the complete immune defence characteristics of the BDS against BBPs through the collaboration of the liver, spleen and BM with combined different immunological roles.

Transmissibility of Mycobacterium pinnipedii in a murine model.

The causative agent of tuberculosis in pinnipeds is Mycobacterium pinnipedii, a member of the Mycobacterium tuberculosis complex (MTC). The natural hosts are pinnipeds; however, other non-marine mammals, including humans, can also be infected. The transmissibility of a pathogen is related to its virulence. The transmissibility of a M. pinnipedii strain (i.e., 1856) was investigated in a murine model and compared with that of two Mycobacterium bovis strains (i.e., 534 and 04-303) with different reported virulence. Non-inoculated mice (sentinels) were co-housed with intratracheally inoculated mice. Detailed inspection of mice to search for visible tuberculosis lesions in the lungs and spleen was performed, and bacillus viability at 30, 60, and 90 days post-inoculation (dpi) was assayed. A transmissibility of 100% was recorded at 30 dpi in sentinel mice co-housed with the inoculated mice from the M. pinnipedii and M. bovis 04-303 groups, as evidenced by the recovery of viable M. pinnipedii and M. bovis from the lungs of sentinel mice. Mice inoculated with M. pinnipedii (1856) and M. bovis (534) survived until euthanized, whereas five of the M. bovis 04-303-inoculated mice died at 17 dpi. This study constitutes the first report of the transmissibility of a M. pinnipedii strain in mice and confirms the utility of this experimental model to study virulence features such as the transmission of poorly characterized MTC species.

[Buzhong Yiqi Decoction ameliorates spleen deficiency syndrome by regulating gut microbiota].

This study aims to decipher the mechanism of Buzhong Yiqi Decoction(BZYQD) in the treatment of spleen deficiency syndrome via gut microbiota. The mouse models of spleen deficiency syndrome were established by fecal microbiota transplantation(FMT, from patients with spleen deficiency syndrome) and administration of Sennae Folium(SF, 10 g·kg~(-1)), respectively, and treated with BZYQD for 5 d. The pseudosterile mice(administrated with large doses of antibiotics) and the mice transplanted with fecal bacteria from healthy human were taken as the controls. The levels of IgA, interleukin(IL)-2, IL-1ß, interferon(IFN)-γ, tumor necrosis factor-alpha(TNF-α), and 5-hydroxytryptamine(5-HT) in the intestinal tissue of two models were measured by enzyme-linked immunosorbent assay, and the CD8~+/CD3~+ ratio was determined by flow cytometry. The composition and changes of the gut microbiota were determined by 16S rRNA high-throughput sequencing and qPCR. Furthermore, the correlation analysis was performed to study the mediating role of gut microbiota in the treatment. The results showed that BZYQD elevated the IgA level, lowered the IL-1ß, TNF-α, and 5-HT levels, and decreased the CD8~+/CD3~+ ratio in the intestinal tissue of the two models. Moreover, BZYQD had two-way regulatory effects on the levels of IL-2 and IFN-γ. BZYQD inhibited the overgrowth and reduced the richness of gut microbiota in the SF model, and improved the gut microbiota structure in the two models. Algoriphagus, Mycobacterium, and CL500＿29＿marine＿group were the common differential genera in the two models compared with the control. Acinetobacter, Parabacteroides, and Ruminococcus were the differential genera unique to the FMT model, and Sphingorhabdus, Lactobacillus, and Anaeroplasma were the unique differential genera in the SF model. BZYQD was capable of regulating all these genera. The qPCR results showed that BZYQD increased the relative abundance of Akkermansia muciniphila and decreased that of Bacteroides uniformis in the two models. The correlation analysis revealed that the levels of above intestinal cytokines were significantly correlated with characteristic gut microorganisms in different mo-dels. The IL-1ß level had a significantly positive correlation with Acinetobacter and CL500＿29＿marine＿group in the two models, while the different levels of IL-2 and IFN-γ in the two models may be related to its different gut microbiota structures. In conclusion, BZYQD could regulate the disordered gut microbiota structure in different animal models of spleen deficiency syndrome to improve the intestinal immune status, which might be one of the mechanisms of BZYQD in treating spleen deficiency syndrome.

A new method to predict venous complications in pediatric liver transplantation: Evaluation of splenic parameters by ultrasonography.

BACKGROUND: Venous complications after pediatric liver transplantation seriously affect the survival rate of patients and grafts. At present, the diagnostic indicators have not been unified. Venous complications may cause portal hypertension, which may lead to splenomegaly and splenic vein dilatation. Therefore, the changes in spleen may be closely related to the venous complications. The purpose of this study was to explore the relationship between ultrasonic splenic parameters and venous complications and to study whether these splenic parameters can be used for the diagnosis of venous complications. METHODS: We retrospectively included pediatric patients who underwent liver transplantation and collected ultrasonic spleen parameters before, and then 1-3 days, 1-3 weeks, 1-3 months, and 4-12 months after liver transplantation. We observed whether there were portal vein or hepatic vein complications within 1 year after liver transplantation. RESULTS: Among 109 pediatric patients after liver transplantation included in our study, 11 of them suffered from portal vein complications and nine hepatic vein complications. Spleen transverse diameter, spleen longitudinal diameter, spleen portal vein diameter, spleen index, spleen transverse diameter ratio, spleen longitudinal diameter ratio, and spleen index ratio were independent risk factors of venous complications. The accuracy of spleen transverse diameter (AUROC: 0.73), spleen index (AUROC: 0.70), spleen transverse diameter ratio (AUROC: 0.71), and spleen index ratio (AUROC: 0.72) in predicting venous complications were higher than other ones. CONCLUSIONS: Ultrasonic examination is a common follow-up method for pediatric patients after liver transplantation and the application of ultrasonic spleen parameters may be helpful to monitor venous complications.

Comparative effectiveness of angioembolization versus open surgery in patients with blunt splenic injury.

The effectiveness and safety of transcatheter splenic artery embolization (SAE) compared to those of open surgery in patients with blunt splenic injury (BSI) remain unclear. This retrospective cohort-matched study utilized data from the Japan Trauma Data Bank recorded between 2004 and 2019. Patients with BSI who underwent SAE or open surgery were selected. A propensity score matching analysis was used to balance the baseline covariates and compare outcomes, including all-cause in-hospital mortality and spleen salvage. From 361,706 patients recorded in the data source, this study included 2,192 patients with BSI who underwent SAE or open surgery. A propensity score matching analysis was used to extract 377 matched pairs of patients. The in-hospital mortality rates (SAE, 11.6% vs. open surgery, 11.2%, adjusted relative risk (aRR): 0.64; 95% confidence interval [CI]: 0.38-1.09, p = 0.10) were similar in both the groups. However, spleen salvage was significantly less achieved in the open surgery group than in the SAE group (SAE, 87.1% vs. open surgery, 32.1%; aRR: 2.84, 95%CI: 2.29-3.51, p < 0.001). Survival rates did not significantly differ between BSI patients undergoing SAE and those undergoing open surgery. Nonetheless, SAE was notably associated with a higher likelihood of successful spleen salvage.

High-altitude hypoxia exposure inhibits erythrophagocytosis by inducing macrophage ferroptosis in the spleen.

High-altitude polycythemia (HAPC) affects individuals living at high altitudes, characterized by increased red blood cells (RBCs) production in response to hypoxic conditions. The exact mechanisms behind HAPC are not fully understood. We utilized a mouse model exposed to hypobaric hypoxia (HH), replicating the environmental conditions experienced at 6000 m above sea level, coupled with in vitro analysis of primary splenic macrophages under 1% O2 to investigate these mechanisms. Our findings indicate that HH significantly boosts erythropoiesis, leading to erythrocytosis and splenic changes, including initial contraction to splenomegaly over 14 days. A notable decrease in red pulp macrophages (RPMs) in the spleen, essential for RBCs processing, was observed, correlating with increased iron release and signs of ferroptosis. Prolonged exposure to hypoxia further exacerbated these effects, mirrored in human peripheral blood mononuclear cells. Single-cell sequencing showed a marked reduction in macrophage populations, affecting the spleen's ability to clear RBCs and contributing to splenomegaly. Our findings suggest splenic ferroptosis contributes to decreased RPMs, affecting erythrophagocytosis and potentially fostering continuous RBCs production in HAPC. These insights could guide the development of targeted therapies for HAPC, emphasizing the importance of splenic macrophages in disease pathology.

The lack of PPARα exacerbated the progression of non-alcoholic steatohepatitis in mice with spleen deficiency syndrome by triggering an inflammatory response.

Background: In addition to abnormal liver inflammation, the main symptoms of non-alcoholic steatohepatitis (NASH) are often accompanied by gastrointestinal digestive dysfunction, consistent with the concept of spleen deficiency (SD) in traditional Chinese medicine. As an important metabolic sensor, whether peroxisome proliferator-activated receptor alpha (PPARα) participates in regulating the occurrence and development of NASH with SD (NASH-SD) remains to be explored. Methods: Clinical liver samples were collected for RNA-seq analysis. C57BL/6J mice induced by folium sennae (SE) were used as an SD model. qPCR analysis was conducted to evaluate the inflammation and metabolic levels of mice. PPARα knockout mice (PPARαko) were subjected to SE and methionine-choline-deficient (MCD) diet to establish the NASH-SD model. The phenotype of NASH and the inflammatory indicators were measured using histopathologic analysis and qPCR as well. Results: The abnormal expression of PPARα signaling, coupled with metabolism and inflammation, was found in the results of RNA-seq analysis from clinical samples. SD mice showed a more severe inflammatory response in the liver evidenced by the increases in macrophage biomarkers, inflammatory factors, and fibrotic indicators in the liver. qPCR results also showed differences in PPARα between SD mice and control mice. In PPARαko mice, further evidence was found that the lack of PPARα exacerbated the inflammatory response phenotype as well as the lipid metabolism disorder in NASH-SD mice. Conclusion: The abnormal NR signaling accelerated the vicious cycle between lipotoxicity and inflammatory response in NAFLD with SD. Our results provide new evidence for nuclear receptors as potential therapeutic targets for NAFLD with spleen deficiency.

[Non-targeted metabolomics of spleen and liver metabolism in mice treated with Pruni Semen processed with different methods].

Ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) was employed to investigate the impacts of Pruni Semen processed with different methods(raw and fried) on the liver and spleen metabolism in mice. A total of 24 male mice were randomly assigned to three groups: raw Pruni Semen group, fried Pruni Semen group, and control(deionized water) group. Mice in the three groups were orally administrated with 0.01 g·mL~(-1) Pruni Semen decoction or deionized water for one week. After that, the liver and spleen tissues were collected, and liquid chromatography-mass spectrometry(LC-MS)-based metabolomic analysis was carried out to investigate the impact of Pruni Semen on the liver and spleen metabolism in mice. Compared with thte control group, the raw Pruni Semen group showed up-regulation of 11 metabolites and down-regulation of 57 metabolites in the spleen(P<0.05), as well as up-regulation of 15 metabolites and down-regulation of 58 metabolites in the liver(P<0.05). The fried Pruni Semen group showed up-regulation of 31 metabolites and down-regulation of 10 metabolites in the spleen(P<0.05), along with up-regulation of 26 metabolites and down-regulation of 61 metabolites in the liver(P<0.05). The differential metabolites identified in the raw Pruni Semen group were primarily associated with alanine, aspartate, and glutamate metabolism, purine metabolism, amino sugar and nucleotide sugar metabolism, and D-glutamine and D-glutamate metabolism. The differential metabolites identified in the fried Pruni Semen group predominantly involved riboflavin metabolism, amino sugar and nucleotide sugar metabolism, purine metabolism, alanine, aspartate, and glutamate metabolism, D-glutamine and D-glutamate metabolism, and glutathione metabolism. The findings suggest that both raw and fried Pruni Semen have the potential to modulate the metabolism of the liver and spleen in mice by influencing the glutamine and glutamate metabolism.

Correlation between spleen density and prognostic outcomes in patients with colorectal cancer after curative resection.

OBJECTIVE: The objective of this study was to investigate the correlation between spleen density and the prognostic outcomes of patients who underwent curative resection for colorectal cancer (CRC). METHODS: The clinical data of patients who were diagnosed with CRC and underwent radical resection were retrospectively analyzed. Spleen density was determined using computed tomography. Analysis of spleen density in relation to overall survival (OS) and disease-free survival (DFS) utilizing the Kaplan-Meier method. Univariate and multivariate Cox regression models were used to screen for independent prognostic factors, and a nomogram was constructed to predict OS and DFS. Moreover, internally validated using a bootstrap resamplling method. RESULTS: Two hundred twelve patients were included, of whom 23 (10.85%) were defined as having a diffuse reduction of spleen density (DROSD) based on diagnostic cutoff values (spleen density≦37.00HU). Kaplan-Meier analysis indicated that patients with DROSD had worse OS and DFS than those non-DROSD (P < 0.05). Multivariate Cox regression analysis revealed that DROSD, carbohydrate antigen 199 (CA199) > 37 U/mL, tumor node metastasis (TNM) stage III-IV, laparoscopy-assisted operation and American Society of Anesthesiology (ASA) score were independent risk factors for 3-year DFS. DROSD, CA199 > 37 U/mL, TNM stage III-IV, hypoalbuminemia, laparoscopy-assisted operation and ASA score were chosen as predictors of for 3-year OS. Nomograms showed satisfactory accuracy in predicting OS and DFS using calibration curves, decision curve analysis and bootstrap resamplling method. CONCLUSION: Patients with DROSD who underwent curative resection have worse 3-year DFS and OS. The nomogram demonstrated good performance, particularly in predicting 3-year DFS with a net clinical benefit superior to well-established risk calculator.

Dynamics of ex vivo cytokine transcription during experimental Toxocara canis infection in Balb/c mice.

The cytokine microenvironment is crucial in generating and polarizing the immune response. A means of monitoring this environment would be of great value for better understanding Toxocara canis immune modulation. The aim of this study was to analyze the dynamics of cytokine transcription ex vivo, during early (24-48 hours) and late (15-30 days) times post-infection, in the mesenteric lymph nodes, spleen and intestinal mucosa of Balb/c mice experimentally infected with T. canis larvae. Mice in the treated group were infected with 100 third-stage larvae (L3), whereas mice in the control group were not infected. Analyses were performed at different times: 24-48 hours post-infection (HPI), 15-30 days post-infection (DPI). IL4, IL10, IL12 and Ym1 mRNA transcriptions were analyzed through qPCR. This study showed cytokine transcription mediated by migrating larvae in the mesenteric lymph nodes and spleen at 24-48 HPI, whereas cytokine transcription in the intestinal mucosa was observed only at late times (15-30 DPI). These results suggest that the T. canis larvae migration during infection might play a role in cytokine dynamics. Since the cytokine microenvironment is crucial in modulating immune response, knowledge of cytokine dynamics during T. canis infections pave the way to better understand its interaction with the host.

Trauma to the solid abdominal organs: The missed dark box of colonoscopy.

Colonoscopy is an integral part of the lower bowel care and is generally considered a potentially safe diagnostic and therapeutic procedure performed as a daycare outpatient procedure. Colonoscopy is associated with different complications that are not limited to adverse events related to the bowel preparation solutions used, the sedatives used, but to the procedure related as well including bleeding and perforation. Injuries to the extra-luminal abdominal organs during colonoscopy are uncommon, however, serious complications related to the procedure have been reported infrequently in the literature. Life threatening injuries to the spleen, liver, pancreas, mesentery, and urinary bladder have been reported as early as in mid-1970s. These injuries should not be overlooked by clinicians and endoscopists. Steadily increasing abdominal pain, abdominal distension, and hemodynamic instability in absence of rectal bleeding should raise the possibility of severe organ injury. Splenic and hepatic injury following colonoscopy are usually serious and may be life threatening. Although conservative management may help, yet they usually need interventional radiology or surgical intervention. Acute pancreatitis following colonoscopy is usually mild and is mostly managed conservatively. The mechanism of abdominal organ injuries during colonoscopy is not fully understood, however many risk factors have been identified, which can be classified as- organ related, procedure related, and local abdominal factors. Difficult colonoscopy and prior intra-abdominal adhesions are probably the most relevant risk factors for these injuries. Left lateral position, avoidance of looping and excessive force during the procedure would probably reduce the risk of such injuries.

Phospholipase D regulates ferroptosis signal transduction in mouse spleen hypoxia response.

High-altitude hypoxia exposure can lead to phospholipase D-mediated lipid metabolism disorder in spleen tissues and induce ferroptosis. Nonetheless, the key genes underlying hypoxia-induced splenic phospholipase D and the ferroptosis pathway remain unclear. This study aimed to establish a hypoxia animal model. Combined transcriptomic and proteomic analyses showed that 95 predicted target genes (proteins) were significantly differentially expressed under hypoxic conditions. Key genes in phospholipase D and ferroptosis pathways under hypoxic exposure were identified by combining Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis techniques. Gene set enrichment analysis (GSEA) showed that the differential gene sets of the phospholipase D and ferroptosis signaling pathways were upregulated in the high-altitude hypoxia group. The genes in the phospholipase D signalling pathway were verified, and the expression levels of KIT and DGKG were upregulated in spleen tissues under hypoxic exposure. Subsequently, the mRNA and protein expression levels of genes from the exogenous pathway such as TFRC, SLC40A1, SLC7A11, TRP53, and FTH1 and those from the endogenous pathway such as GPX4, HMOX1, and ALOX15 differentials in the ferroptosis signalling pathway were verified, and the results indicated significant differential expression. In summary, exposure to high-altitude hypoxia mediated phospholipid metabolism disturbance through the phospholipase D signalling pathway and further induced ferroptosis, leading to splenic injury.

Persistent disparities between trauma center types in the management of children with high-grade blunt splenic injuries.

BACKGROUND: In the early 2000s, substantial variations were reported in the management of pediatric patients with blunt splenic injury (BSI). The purpose of this study was to assess the recent trends and disparities between different types of trauma centers. We hypothesized that there would be persistent disparities despite decreased trends in the rate of splenectomy. METHODS: This is a retrospective cohort study using the American College of Surgeons Trauma Quality Improvement Program database. We included patients (age ≤18 years) with high-grade BSI (Abbreviated Injury Scale 3-5) between 2014 and 2021. The patients were divided into three groups based on trauma center types (adult trauma centers [ATCs], mixed trauma centers [MTCs], and pediatric trauma centers [PTCs]). The primary outcome was the splenectomy rate. Logistic regression was performed to evaluate the association between trauma center types and clinical outcomes. Additionally, the trends in the rate of splenectomy at ATCs, MTCs, and PTCs were evaluated. RESULTS: A total of 6601 patients with high-grade BSI were included in the analysis. Overall splenectomy rates were 524 (17.5%), 448 (16.3%), and 32 (3.7%) in the ATC, MTC, and PTC groups, respectively. ATCs and MTCs had significantly higher splenectomy rates compared to PTCs (ATCs: OR = 5.72, 95%CI = 3.78-8.67, and p < 0.001 and MTCs: OR = 4.50, 95%CI = 2.97-6.81, and p < 0.001), while decreased trends in the splenectomy rates were observed in ATCs and MTCs (ATCs: OR = 0.92, 95%CI = 0.87-0.97, and p = 0.003 and MTCs: OR = 0.92, 95%CI = 0.87-0.98, and p = 0.013). CONCLUSIONS: This study suggested persistent disparities between different trauma center types in the management of children with high-grade BSI.

Repeat imaging increases detection of delayed pseudoaneurysms in patients with high-grade solid organ injury following abdominal trauma.

BACKGROUND: Nonoperative management of abdominal trauma can be complicated by the development of delayed pseudoaneurysms. Early intervention reduces the risk of rupture and decreases mortality. The objective of this study is to determine the utility of repeat computed tomography (CT) imaging in detecting delayed pseudoaneurysms in patients with abdominal solid organ injury. METHODS: A retrospective cohort study reviewing Montreal General Hospital registry between 2013 and 2019. Patients with The American Association for the Surgery of Trauma (AAST) grade 3 or higher solid organ injury following abdominal trauma were identified. A chart review was completed, and demographics, mechanism of injury, Injury Severity Score (ISS) score, AAST injury grade, CT imaging reports, and interventions were collected. Descriptive analysis and logistic regression model were completed. RESULTS: We identified 195 patients with 214 solid organ injuries. The average age was 38.6 years; 28.2% were female, 90.3% had blunt trauma, and 9.7% had penetrating trauma. The average ISS score was 25.4 (SD 12.8) in patients without pseudoaneurysms and 19.5 (SD 8.6) in those who subsequently developed pseudoaneurysms. The initial management was nonoperative in 57.0% of the patients; 30.4% had initial angioembolization, and 12.6% went to the operating room. Of the cohort, 11.7% had pseudoaneurysms detected on repeat CT imaging within 72 h. Grade 3 represents the majority of the injuries at 68.0%. The majority of these patients underwent angioembolization. CONCLUSIONS: In patients with high-grade solid organ injury following abdominal trauma, repeat CT imaging within 72 h enabled the detection of delayed development of pseudoaneurysms in 11.7% of injuries. The majority of the patients were asymptomatic.

Oral subacute polypropylene microplastics administration effect on potential immunotoxicity in ICR mice.

Exposure to microplastics may be associated with damage of immune system. Polypropylene microplastics (PP-MPs) with a wide range of beneficial applications have not been extensively studied with respect to the immune system. The aim of this investigation is to examine the influence of two different sizes of PP-MPs (5.2 and 23.9 µm diameter) on immune system components in ICR mice. PP-MPs were administered orally to female and male mice at 0 (corn oil vehicle), 500, 1000, or 2000 mg/kg/d for single and daily for 4-week repeated toxicity test, respectively. No significant differences were observed in number of thymic CD4+, CD8+, CD4+CD8+ T lymphocytes, splenic helper T cells, cytotoxic T cells, and B cells. The ratio of interferon-γ to interleukin-4 in culture supernatants from activated splenocytes ex vivo (48 hr) was lower in females which were repeatedly administered with PP-MPs compared to vehicle irrespective of PP-MPs size and dose. In contrast, the opposite trend was observed in males. Production of tumor necrosis factor-α was upregulated in females that were repeatedly exposed to PP-MPs. The serum IgG2a/IgG1 ratio was lowered in female receiving large-size PP-MPs. Data suggest that immune disturbances resulting in predominant type-2 helper T cell reactivity may occur in mice, especially in females, when repeatedly exposed to PP-MPs. Further investigations with longer exposure periods are necessary to determine the immunotoxicities attributed to PP-MPs.

Non-operative Management - The First Option in the Treatment of Blunt Liver and Spleen Trauma in Pediatric Patients.

AIM: The aim of the present study is to assess some characteristics of blunt hepatic and splenic injuries in children, the non-operative management (NOM) procedures and efficiency, over a 5-year period in a tertiary hospital for children. Materials and Methods: We conducted a retrospective study on 32 patients with blunt liver and/or spleen injuries. Age, gender, mechanism of injury, hemoglobin and hematocrit levels, lenght of stay and bedrest, imaging diagnosis, hemostatics and transfusions, treatment, and discharge status were evaluated. Results: 58% of patients were males. Mean age was 10.7 years. The main mechanism of injury was motor vehicle accident. Ultrasound (US) and Computed Tomography (CT) found 56.2% patients with spleen injury and 43.8% with liver injuries. On US the most frequent injuries were lacerations, and on CT were splenic-grade III and hepatic-grade II. 84.4% of patients were hospitalized in Intensive Care Unit and 15.6% in the surgical unit. The mean hemoglobin and hematocrit were 10.91g/l and 33%, respectively.The treatment was non-operative for 84.4%, and operative for 15.6%. When discharged, 56.2% of patients were cured and 43.8% were improved. CONCLUSION: With a performing multidisciplinary team of surgeons, intensive care therapists and radiologists, NOM in pediatric patients with blunt liver and spleen injuries is safe and effective, may be conducted depending on the hemodynamic stability rather than the lesions' extension, and reduces the ICU lenght of stay, as well as the need for hemostatics and transfusion.