Adipose-derived stem cell modulate tolerogenic dendritic cell-induced T cell regulation is correlated with activation of Notch-NFκB signaling.

BACKGROUND: Adipose-derived stem cells (ASCs) are recognized for their potential immunomodulatory properties. In the immune system, tolerogenic dendritic cells (DCs), characterized by an immature phenotype, play a crucial role in inducing regulatory T cells (Tregs) and promoting immune tolerance. Notch1 signaling has been identified as a key regulator in the development and function of DCs. However, the precise involvement of Notch1 pathway in ASC-mediated modulation of tolerogenic DCs and its impact on immune modulation remain to be fully elucidated. This study aims to investigate the interplay between ASCs and DCs, focusing the role of Notch1 signaling and downstream pathways in ASC-modulated tolerogenic DCs. METHODS: Rat bone marrow-derived myeloid DCs were directly co-cultured with ASCs to generate ASC-treated DCs (ASC-DCs). Notch signaling was inhibited using DAPT, while NFκB pathways were inhibited by NEMO binding domain peptide and si-NIK. Flow cytometry assessed DC phenotypes. Real-time quantitative PCR, Western blotting and immunofluorescence determined the expression of Notch1, Jagged1 and the p52/RelB complex in ASC- DCs. RESULTS: Notch1 and Jagged1 were highly expressed on both DCs and ASCs. ASC-DCs displayed significantly reduced levels of CD80, CD86 and MHC II compared to mature DCs. Inhibiting the Notch pathway with DAPT reversed the dedifferentiation effects. The percentage of induced CD25+/FOXP3+/CD4+ Tregs decreased when ASC-DCs were treated with DAPT (inhibition of the Notch pathway) and si-NIK (inhibition of the non-canonical NFκB pathway). CONCLUSIONS: ASCs induce DC tolerogenicity by inhibiting maturation and promoting downstream Treg generation, involving the Notch and NFκB pathways. ASC-induced tolerogenic DCs can be a potential immunomodulatory tool for clinical application.

Relationship between the Number of Repeats in the Neck Regions of L-SIGN and Augmented Virus Replication and Immune Responses in Dengue Hemorrhagic Fever.

C-type lectins play a crucial role as pathogen-recognition receptors for the dengue virus, which is responsible for causing both dengue fever (DF) and dengue hemorrhagic fever (DHF). DHF is a serious illness caused by the dengue virus, which exists in four different serotypes: DEN-1, DEN-2, DEN-3, and DEN-4. We conducted a genetic association study, during a significant DEN-2 outbreak in southern Taiwan, to explore how variations in the neck-region length of L-SIGN (also known as CD209L, CD299, or CLEC4M) impact the severity of dengue infection. PCR genotyping was utilized to identify polymorphisms in variable-number tandem repeats. We constructed L-SIGN variants containing either 7- or 9-tandem repeats and transfected these constructs into K562 and U937 cells, and cytokine and chemokine levels were evaluated using enzyme-linked immunosorbent assays (ELISAs) following DEN-2 virus infection. The L-SIGN allele 9 was observed to correlate with a heightened risk of developing DHF. Subsequent results revealed that the 9-tandem repeat was linked to elevated viral load alongside predominant T-helper 2 (Th2) cell responses (IL-4 and IL-10) in K562 and U937 cells. Transfecting K562 cells in vitro with L-SIGN variants containing 7- and 9-tandem repeats confirmed that the 9-tandem repeat transfectants facilitated a higher dengue viral load accompanied by increased cytokine production (MCP-1, IL-6, and IL-8). Considering the higher prevalence of DHF and an increased frequency of the L-SIGN neck's 9-tandem repeat in the Taiwanese population, individuals with the 9-tandem repeat may necessitate more stringent protection against mosquito bites during dengue outbreaks in Taiwan.

A Multifunctional Polyethylene Glycol/Triethoxysilane-Modified Polyurethane Foam Dressing with High Absorbency and Antiadhesion Properties Promotes Diabetic Wound Healing.

The delayed healing of chronic wounds, such as diabetic foot ulcers (DFUs), is a clinical problem. Few dressings can promote wound healing by satisfying the demands of chronic wound exudate management and tissue granulation. Therefore, the aim of this study was to prepare a high-absorption polyurethane (PU) foam dressing modified by polyethylene glycol (PEG) and triethoxysilane (APTES) to promote wound healing. PEG-modified (PUE) and PEG/APTES-modified (PUESi) dressings were prepared by self-foaming reactions. Gauze and PolyMem were used as controls. Next, Fourier transform-infrared spectroscopy, thermomechanical analyses, scanning electron microscopy and tensile strength, water absorption, anti-protein absorption, surface dryness and biocompatibility tests were performed for in vitro characterization. Wound healing effects were further investigated in nondiabetic (non-DM) and diabetes mellitus (DM) rat models. The PUE and PUESi groups exhibited better physicochemical properties than the gauze and PolyMem groups. Moreover, PUESi dressing showed better anti-adhesion properties and absorption capacity with deformation. Furthermore, the PUESi dressing shortened the inflammatory phase and enhanced collagen deposition in both the non-DM and DM animal models. To conclude, the PUESi dressing not only was fabricated with a simple and effective strategy but also enhanced wound healing via micronegative-pressure generation by its high absorption compacity with deformation.

Proteomic Analysis of Peri-Wounding Tissue Expressions in Extracorporeal Shock Wave Enhanced Diabetic Wound Healing in a Streptozotocin-Induced Diabetes Model.

Our former studies have demonstrated that extracorporeal shock wave therapy (ESWT) could enhance diabetic wound healing but the bio-mechanisms remain elusive. This study investigated the changes of topical peri-wounding tissue expressions after ESWT in a rodent streptozotocin-induced diabetic wounding model by using the proteomic analysis and elucidated the molecular mechanism. Diabetic rats receiving ESWT, normal control, and diabetic rats receiving no therapy were analyzed. The spots of interest in proteome analysis were subjected to mass spectrometry to elucidate the peptide mass fingerprints. Protein expression was validated using immunohistochemical staining and related expression of genes were analyzed using real-time RT-PCR. The proteomic data showed a significantly higher abundance of hemopexin at day 3 of therapy but down-regulation at day 10 as compared to diabetic control. In contrast, the level of serine proteinase inhibitor (serpin) A3N expression was significantly decreased at day 3 therapy but expression was upregulated at day 10. Using real-time RT-PCR revealed that serpin-related EGFR-MAPK pathway was involved in ESWT enhanced diabetic wound healing. In summary, proteome analyses demonstrated the expression change of hemopexin and serpin with related MAPK signaling involved in ESWT-enhanced diabetic wound healing. Modulation of hemopexin and serpin related pathways are good strategies to promote wound healing.

Modulation of vascular endothelial growth factor and mitogen-activated protein kinase-related pathway involved in extracorporeal shockwave therapy accelerate diabetic wound healing.

Extracorporeal shockwave therapy (ESWT) has a significant positive effect to accelerate chronic wound healing. This study investigated whether the vascular endothelial growth factor (VEGF)-related pathway has involved in ESWT enhancement of diabetic wound healing. A dorsal skin defect (area, 6 × 5 cm) in a streptozotocin-induced diabetes rodent model was used. Thirty-two male Wistar rats were divided into four groups. Group I consisted of nondiabetic control; group II, diabetic control without treatment; group III, diabetic rats received ESWT; and group IV, rats received Avastin (a VEGF monoclonal antibody) on day 0 (post-wounding immediately) to day 7 and ESWT on day 3 and day 7. The wound healing was assessed clinically. The VEGF, endothelial nitric oxide synthase (eNOS), and Ki-67 were analyzed with immunohistochemical staining. The mRNA expression of mitogen-activated protein kinase-related genes was measured by real-time quantitative real-time polymerase chain reaction. The results revealed wound size was significantly reduced in the ESWT-treated rats as compared to the diabetic control (p < 0.01). The positive effect of ESWT-increasing wound healing was significantly suppressed in pretreatment of the Avastin group. Histological findings revealed significant increase in neo-vessels in the ESWT group as compared to the control. In immunohistochemical stain, significant increases in VEGF, eNOS, and Ki-67 expressions were noted in the ESWT group as compared to that in controls. However, Avastin suppressed the shockwave effect and down-regulation of VEGF, eNOS, and Ki-67 expressions in the Avastin-ESWT group as compared to that in the ESWT alone group. We found that highly mRNA expression of Kras, Raf1, Mek1, Jnkk, Jnk, and Jun at early stage in the ESWT group, as compared to the diabetic control. These evidences indicated treatment with multiple sessions of ESWT significantly enhanced diabetic wound healing associated with increased neovascularization and tissue regeneration. The bio-mechanism of ESWT-enhanced wound healing is correlated with VEGF and mitogen-activated protein kinase-mediated pathway.

The suppression effect of dendritic cells maturation by adipose-derived stem cells through TGF-ß1 related pathway.

BACKGROUND: Our previous studies demonstrated that adipose-derived stem cells (ASCs) could modulate regulatory T cells (Treg) and prolong hind-limb allotransplant survival in vitro and in vivo. Dendritic cells (DCs) play a pivotal role in innate and adaptive immunity. The aim of this study is to investigate the underlying mechanism of ASCs in modulating DC maturation. MATERIALS AND METHODS: ASCs were isolated from rodent adipose tissue, DCs were derived from the bone marrow, and CD4+ T cells were purified from splenocytes. DCs were co-cultured with ASCs to evaluate the suppressive effects of ASCs. CD4+ T-cells were co-cultured with DCs pre-treated with or without ASCs. The cell surface markers of DCs were analyzed by flow cytometry. T-cell proliferation was analyzed by the BrdU proliferation test. Tolerogenic cytokines and indoleamine 2,3-dioxygenase (IDO) expressions after different treatments were detected by quantitative real-time PCR, Western blotting, and ELISA analysis. RESULT: ASCs suppressed DC maturation as evidenced by low expressions of CD80, CD86, and MHC-II. Also, ASC-treated mature DCs showed higher levels of TGF-ß1, IL-10, and IDO expressions, as compared to that in matured DCs (mDCs) alone. ASC-treated mDCs co-cultured with CD4+ T cells revealed a significant higher percentage of Treg than mDC without treatment. The IDO level in ASC-treated mDCs and Treg induction effects were blocked by the ASCs pre-treated with TGF-ß1 siRNAs, but not IL-10 siRNAs. CONCLUSION: ASC-modulated DC maturation correlated with TGF-ß1 secretion, IDO expression, and Treg induction. ASCs could be used as a potential immunomodulatory strategy for clinical application in allotransplantation.

Suppression of Oxygen Radicals Protects Diabetic Endothelium Damage and Tissue Perfusion in a Streptozotocin-Induced Diabetes Rodent Model.

BACKGROUND: Oxygen free radicals play a central role in diabetic angiopathy. This study investigated whether suppression of oxygen radicals could decrease endothelial damage and increase peripheral tissue circulation in a diabetic rodent model. METHODS: Sprague-Dawley rats were treated using streptozotocin to induce diabetes. The experiments were performed 4 weeks after diabetes induction: group 1: control, consisted of normal rats; group 2: diabetes, did not receive treatment; groups III (SOD10) and IV (SOD50): diabetes, received polyethylene glycol-conjugated superoxide dismutase (SOD), an antioxidant, 10 and 50 U/kg per day intraperitoneally for 4 weeks. Each subgroup consisted of 10 rats. Oxygen radicals in blood mononuclear cells were detected by flow cytometry. The blood lipid peroxidation byproduct malondialdehyde was measured. Tissue perfusion of hind limb was examined by laser Doppler. The expressions of oxygen radicals, as demonstrated by 8-hydroxyguanosine (8-OG), and constitutive endothelial nitric oxide synthase in distal femoral vessels were examined by immunohistochemical staining. RESULTS: Oxygen radicals, as demonstrated by H2O2 with 2',7'-dichlorofluorescin diacetate-conjugated expression, were significantly increased in diabetic rats. However, the SOD treatment groups significantly suppressed the H2O2 reaction. Diabetic-induced high malondialdehyde levels were significantly suppressed in the SOD50 group. The topical tissue blood perfusion was significantly increased as detected by laser Doppler in SOD10 and SOD50 groups, as compared with that in diabetes without treatment group (P < 0.05). The expression of 8-OG was markedly increased in the diabetic endothelium and subintima compared with that in normal vessels. Polyethylene glycol-conjugated SOD significantly suppressed 8-OG expression and protected endothelial nitric oxide synthase expression. CONCLUSIONS: Suppression of oxygen radicals, particularly with the higher dosage of polyethylene glycol-conjugated SOD at 50 U/kg per day, could have a positive effect to protect against endothelial damage and enhance peripheral perfusion in diabetes.

Triamcinolone Acetonide Suppresses Keloid Formation Through Enhancing Apoptosis in a Nude Mouse Model.

BACKGROUND: Current understanding of steroid treatments for keloids is in regards to modulation of inflammation, proliferation, and apoptosis, with no in vivo study on the latter. Using a nude mouse model, we investigated whether triamcinolone acetonide (TA) injections induce keloids regression through enhancing apoptosis. MATERIALS AND METHODS: Thirty-six keloid specimens (1 × 1 cm) were harvested from 6 patients and separated into sets of 2 from the same patient: no treatment and intralesional TA injection (0.4 mg/mL/kg) at 8 weeks of postimplantation. One set was implanted in each of 18 randomly selected nude mice, which were separated into 3 groups based on time of keloid harvesting after treatment: group A, 2 weeks; group B, 8 weeks; and group C, 14 weeks. Each group had 1 set of specimen from each patient. Histological staining was performed with hematoxylin and eosin stain. Immunohistochemistry staining was performed for human-prolyl 4-hydroxylase (hPH4) and caspase 3 protein, along with terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. RESULTS: All keloid specimens survived, with no noted overgrowth. Hematoxylin and eosin staining revealed dense extracellular matrix and viable fibroblasts, and hPH4 immunohistochemistry revealed strong expression, demonstrating keloid viability. Caspase 3 protein and TUNEL expressions were significantly increased in the treatment versus control groups, demonstrating that TA injections induced apoptosis. CONCLUSIONS: Triamcinolone acetonide intralesional injections significantly increased apoptosis in keloids, represented by increased caspase 3 protein and TUNEL expressions, supporting that steroids suppress keloids in part owing to enhancement of apoptosis.

Three Simple Steps for Refining Transcutaneous Lower Blepharoplasty for Aging Eyelids: The Indispensability of Micro-Autologous Fat Transplantation.

BACKGROUND: Lower blepharoplasty has been used for rejuvenating lower eyelids, and diverse modifications have been used to treat conjunct deformities at the tear trough/lid-cheek junction. Strategies for recontouring prominent tear trough/lid-cheek junctions, including orbital fat manipulation, have been reported with good results in the literature. Micro-autologous fat transplantation (MAFT) is a previously unevaluated, potentially advantageous approach to blending the prominent tear trough/lid-cheek junction. OBJECTIVES: We determined the long-term results after 3-step transcutaneous lower blepharoplasty with MAFT for patients with aging eyelids and prominent tear trough/lid-cheek junctions. METHODS: We evaluated 205 patients with aging lower eyelids who underwent transcutaneous lower blepharoplasty with MAFT between October 2010 and September 2016. The 3-step procedure involved a subciliary elliptical skin excision, resection of 3 orbital fat compartments, and MAFT for the tear trough/lid-cheek junction employing a MAFT-GUN under intravenous anesthesia. RESULTS: The mean patient age was 52 years (range, 34-78 years). The mean operating time was 61 minutes. The mean fat volumes delivered to the tear trough/lid-cheek junctions were 2.80 mL and 2.76 mL for the left and right sides, respectively. The average weights of the 3 resected orbital fat compartments were 0.58 g for the left side and 0.56 g for the right side. Patients showed significant improvement and maintenance at an average follow-up of 60.2 months (range, 18-90 months). CONCLUSIONS: Three-step transcutaneous lower blepharoplasty with MAFT is an effective, reliable, and promising method with high patient satisfaction and minimal risk of complications. Long-term results demonstrated its utility for aging lower eyelid treatment.

Early Hyperbaric Oxygen Treatment Attenuates Burn-Induced Neuroinflammation by Inhibiting the Galectin-3-Dependent Toll-Like Receptor-4 Pathway in a Rat Model.

Hyperbaric oxygen (HBO) treatment has been proven to decrease neuroinflammation in rats. This study aimed to determine the potential mechanism underlying the anti-inflammatory effects of HBO treatment on burn-induced neuroinflammation in rats. Thirty-six adult male Sprague-Dawley (SD) rats were randomly assigned to the following six groups (n = 6 per group): (1) sham burn with sham HBO treatment; (2) sham burn with HBO treatment; (3) burn with one-week sham HBO treatment; (4) burn with two-week sham HBO treatment; (5) burn with one-week HBO treatment; and (6) burn with two-week HBO treatment. SD rats that received third-degree burn injury were used as a full-thickness burn injury model. Subsequently, we analyzed the expression of proteins involved in the galectin-3 (Gal-3)-dependent Toll-like receptor-4 (TLR-4) pathway through enzyme-linked immunosorbent assay (ELISA), immunohistochemistry (IHC) analysis, and Western blotting. A behavior test was also conducted, which revealed that HBO treatment significantly suppressed mechanical hypersensitivity in the burn with HBO treatment group compared to the burn with sham HBO treatment group (p < 0.05). ELISA results showed that tumor necrosis factor α (TNF-α) and interleukin 1 beta (IL-1ß) levels in the dorsal horn of the spinal cord and the skin significantly decreased in the burn with HBO treatment group compared with the burn with sham HBO treatment group (p < 0.05). Western blotting results demonstrated that HBO treatment significantly reduced the expression of Gal-3 and TLR-4 in the dorsal horn of the spinal cord in the burn with HBO treatment group compared with the burn with sham HBO treatment group (p < 0.05). IHC analysis showed that the expression of Gal-3, TLR-4, CD68 and CD45 in the dorsal horn of the spinal cord was significantly lower in the burn with HBO treatment group than in the burn with sham HBO treatment group (p < 0.05), and the expression of CD68 and macrophage migration inhibitory factor (MIF) in the right hind paw skin was significantly lower. The expression of vimentin and fibroblast growth factor in the right hind paw skin was significantly higher after HBO treatment (p < 0.05). This study proved that early HBO treatment relieves neuropathic pain, inhibits the Gal-3-dependent TLR-4 pathway, and suppresses microglia and macrophage activation in a rat model.

The effects of the location of cancer stem cell marker CD133 on the prognosis of hepatocellular carcinoma patients.

BACKGROUND: CD133 (prominin-1) is widely believed to be a cancer stem cell marker in various solid tumor types, and CD133 has been correlated with tumor-initiating capacity. Recently, the nuclear location of CD133 expression in tumors has been discussed, but hepatocellular carcinoma (HCC) has not been included in these discussions. The goal of this study was to investigate the location of CD133 expression in HCC and this location's potential value as a prognostic indicator of survival in patients with HCC. METHODS: We enrolled 119 cancerous tissues and pair-matched adjacent normal liver tissue from HCC patients. These tissues were obtained immediately after operation, and tissue microarrays were subsequently constructed. The expression of CD133 was measured by immunohistochemistry (IHC), and the correlations between this expression and clinical characteristics and prognosis was estimated using statistical analysis. RESULTS: The results showed that the CD133 protein expression levels of HCC in both the cytoplasm and nucleus were significantly higher than adjacent normal liver tissue. Kaplan-Meier survival and Cox regression analyses revealed that high CD133 expression in the cytoplasm was an independent predictor of poor prognosis for the overall survival (OS) and relapse-free survival (RFS) rates of HCC patients (P = 0.028 and P = 0.046, respectively). Surprisingly, high nuclear CD133 expression of HCC was an independent predictor of the good prognosis of the OS and RFS rates of HCC patients (P = 0.023 and P = 0.012, respectively). CONCLUSIONS: The clinical evidence that revealed cytoplasmic CD133 expression was correlated with poor prognosis, while nuclear CD133 expression was significantly correlated with favorable prognosis.

Role of CAPE on cardiomyocyte protection via connexin 43 regulation under hypoxia.

Background: Cardiomyocyte under hypoxia cause cell death or damage is associated with heart failure. Gap junction, such as connexin 43 play a role in regulation of heart function under hypoxia. Caffeic acid phenethyl ester (CAPE) has been reported as an active component of propolis, has antioxidative, anti-inflammatory antiproliferative and antineoplastic biological properties. Aims: Connexin 43 appear to have a critical role in heart failure under hypoxia, there has been considerable interest in identifying the candidate component or compound to reduce cell death. Methods: In this study, we used human cardiomyocyte as a cell model to study the role of connexin 43 in hypoxia- incubated human cardiomyocyte in absence or presence of CAPE treatment. Results: Results showed that hypoxia induced connexin 43 expression, but not altered in connexin 40. Interestingly, CAPE attenuates hypoxia-caused connexin 43 down-regulation and cell death or cell growth inhibition. Conclusion: We suggested that reduction of cell death in cardiomyocytes by CAPE is associated with an increase in connexin 43 expression.

Beneficial effects of bipolar hemiarthroplasty replacement and fosamax in the retrospective cohort study of refracture and mortality of hip fractured patients.

The epidemiological hip fracture leads to a high death rate in the elderly with osteoporosis worldwide. However, the appropriate surgical styles or anti-osteoporotic therapy could prevent these patients with hip fractures from suffering refracture, but the efficacy of such treatment remains elusive for first hip fractured patients. Our retrospective analysis was conducted on 508 hip fracture patients who were enrolled from Show Chwan Memorial Hospital from January 2005 through December 2011 and followed up until the end of 2012. However, bipolar hemiarthroplasty replacement and open reduction internal fixation (ORIF) are treatment options for femoral neck and intertrochanic hip fracture in our study population. Among these patients, 82 suffered 2nd hip fracture (refracture) with femoral neck or intertrochanteric fracture and 39 died after surgical intervention accompanied complications. Kaplan-Meier analysis revealed a better outcome in patients with bipolar hemiarthroplasty replacement or fosamax therapy of hip fractured patients than those with femoral neck/ORIF and intertrochanteric/ORIF or without fosamax therapy. Multivariate cox regression analysis revealed the lowest incidence of refracture and mortality in hip fracture patients with received bipolar hemiarthroplasty replacement surgical intervention (OR=0.732, CI=0.587-0.912; P=0.006). It is therefore concluded that fosamax therapy may improve bone density and increase bone tissue repair to prevent patients with hip fracture from refracture, and bipolar hemiarthroplasty replacement may promote patients who undertake outdoor activities to produce more vitamin D than those who have received ORIF.

Physiological characterization of aluminum tolerance and accumulation in tartary and wild buckwheat.

Ionic aluminum (Al) is toxic for plant growth, but some plant species are able to accumulate Al at high concentrations without showing toxicity symptoms. In order to determine whether other species in the genus Fagopyrum are able to accumulate Al like common buckwheat (Fagopyrum esculentum), we investigated the external and internal detoxification mechanisms of Al in two self-compatible species: tartary (Fagopyrum tataricum) and wild buckwheat (Fagopyrum homotropicum). Both tartary and wild buckwheat showed high Al tolerance comparable to common buckwheat. Furthermore, these two species also secreted oxalate rapidly from the roots in response to Al in a time-dependent manner. Both tartary and wild buckwheat accumulated > 1 mg g(-1) Al in the leaves after short-term exposure to Al. Analysis with (27) Al-nuclear magnetic resonance (NMR) revealed that Al was present in the form of Al-oxalate (1 : 3 ratio) in the roots and leaves, but in the form of Al-citrate (1 : 1 ratio) in the xylem sap in both species. These results indicate that similar to common buckwheat, both tartary and wild buckwheat detoxify Al externally and internally, respectively, by secreting oxalate from the roots and by forming the Al-oxalate complex, which is a nonphytotoxic form. These features of Al response and accumulation may be conserved in genus Fagopyrum.

Altered cell wall properties are responsible for ammonium-reduced aluminium accumulation in rice roots.

The phytotoxicity of aluminium (Al) ions can be alleviated by ammonium (NH4(+)) in rice and this effect has been attributed to the decreased Al accumulation in the roots. Here, the effects of different nitrogen forms on cell wall properties were compared in two rice cultivars differing in Al tolerance. An in vitro Al-binding assay revealed that neither NH4(+) nor NO3(-) altered the Al-binding capacity of cell walls, which were extracted from plants not previously exposed to N sources. However, cell walls extracted from NH4(+)-supplied roots displayed lower Al-binding capacity than those from NO3(-)-supplied roots when grown in non-buffered solutions. Fourier-transform infrared microspectroscopy analysis revealed that, compared with NO3(-)-supplied roots, NH4(+)-supplied roots possessed fewer Al-binding groups (-OH and COO-) and lower contents of pectin and hemicellulose. However, when grown in pH-buffered solutions, these differences in the cell wall properties were not observed. Further analysis showed that the Al-binding capacity and properties of cell walls were also altered by pHs alone. Taken together, our results indicate that the NH4(+)-reduced Al accumulation was attributed to the altered cell wall properties triggered by pH decrease due to NH4(+) uptake rather than direct competition for the cell wall binding sites between Al(3+) and NH4(+).

Aluminium alleviates manganese toxicity to rice by decreasing root symplastic Mn uptake and reducing availability to shoots of Mn stored in roots.

BACKGROUND AND AIMS: Manganese (Mn) and aluminium (Al) phytotoxicities occur mainly in acid soils. In some plant species, Al alleviates Mn toxicity, but the mechanisms underlying this effect are obscure. METHODS: Rice (Oryza sativa) seedlings (11 d old) were grown in nutrient solution containing different concentrations of Mn(2+) and Al(3+) in short-term (24 h) and long-term (3 weeks) treatments. Measurements were taken of root symplastic sap, root Mn plaques, cell membrane electrical surface potential and Mn activity, root morphology and plant growth. KEY RESULTS: In the 3-week treatment, addition of Al resulted in increased root and shoot dry weight for plants under toxic levels of Mn. This was associated with decreased Mn concentration in the shoots and increased Mn concentration in the roots. In the 24-h treatment, addition of Al resulted in decreased Mn accumulation in the root symplasts and in the shoots. This was attributed to higher cell membrane surface electrical potential and lower Mn(2+) activity at the cell membrane surface. The increased Mn accumulation in roots from the 3-week treatment was attributed to the formation of Mn plaques, which were probably related to the Al-induced increase in root aerenchyma. CONCLUSIONS: The results show that Al alleviated Mn toxicity in rice, and this could be attributed to decreased shoot Mn accumulation resulting from an Al-induced decrease in root symplastic Mn uptake. The decrease in root symplastic Mn uptake resulted from an Al-induced change in cell membrane potential. In addition, Al increased Mn plaques in the roots and changed the binding properties of the cell wall, resulting in accumulation of non-available Mn in roots.

Proteomic analysis of a high aluminum tolerant yeast Rhodotorula taiwanensis RS1 in response to aluminum stress.

Rhodotorula taiwanensis RS1 is a high-aluminum (Al)-tolerant yeast that can survive in Al concentrations up to 200mM. The mechanisms for the high Al tolerance of R. taiwanensis RS1 are not well understood. To investigate the molecular mechanisms underlying Al tolerance and toxicity in R. taiwanensis RS1, Al toxicity-induced changes in the total soluble protein profile were analyzed using two-dimensional gel electrophoresis (2-DE) coupled with mass spectrometry. A total of 33 differentially expressed proteins responding to Al stress were identified from approximately 850 reproducibly detected proteins. Among them, the abundance of 29 proteins decreased and 4 increased. In the presence of 100mM Al, the abundance of proteins involved in DNA transcription, protein translation, DNA defense, Golgi functions and glucose metabolism was decreased. By contrast, Al treatment led to increased abundance of malate dehydrogenase, which correlated with increased malate dehydrogenase activity and the accumulation of intracellular citrate, suggesting that Al-induced intracellular citrate could play an important role in detoxification of Al in R. taiwanensis RS1.

Aspirin enhances opsonophagocytosis and is associated to a lower risk for Klebsiella pneumoniae invasive syndrome.

BACKGROUND: Klebsiella pneumoniae (KP) expressing hypermucoviscosity phenotype (HV-KP) has abundant capsular polysaccharide (CPS) and is capable of causing invasive syndrome. Sodium salicylate (SAL) reduces the production of CPS. The study was aimed to investigate the relationship between aspirin usage and KP-mediated invasive syndrome and the effect of SAL on HV-KP. METHODS: Patients with community-acquired KP bacteraemia were prospectively enrolled. KP-M1, a serotype-K1 HV-KP clinical isolate, was used in the following experiments: CPS production, HV-KP phenotype, and the effect of SAL on neutrophils phagocytosis. The effect of oral aspirin intake on the leukocyte bactericidal activity was evaluated. RESULTS: Patients infected by HV-KP and diabetic patients with poor glycemic control were at an increased risk for invasive syndrome (p < 0.01); those who had recent use of aspirin (p = 0.02) were at a lower risk. CPS production was significantly reduced in the presence of SAL. The HV-KP phenotype and resistance to neutrophil phagocytosis were both significantly reduced in the KP-M1 after incubation with SAL (p < 0.01). Aspirin treatment significantly enhanced the killing of KP-M1 by leukocytes (p < 0.01). CONCLUSION: Treatment with SAL significantly reduces CPS production in HV-KP, thereby contributing to leukocyte phagocytosis and bactericidal activity against this pathogen.

Cell therapies and its derivatives as immunomodulators in vascularized composite allotransplantation.

The adverse effects of traditional pharmaceutical immunosuppressive regimens have been a major obstacle to successful allograft survival in vascularized composite tissue allotransplantation (VCA) cases. Consequently, there is a pressing need to explore alternative approaches to reduce reliance on conventional immunotherapy. Cell therapy, encompassing immune-cell-based and stem-cell-based regimens, has emerged as a promising avenue of research. Immune cells can be categorized into two main systems: innate immunity and adaptive immunity. Innate immunity comprises tolerogenic dendritic cells, regulatory macrophages, and invariant natural killer T cells, while adaptive immunity includes T regulatory cells and B regulatory cells. Investigations are currently underway to assess the potential of these immune cell populations in inducing immune tolerance. Furthermore, mixed chimerism therapy, involving the transplantation of hematopoietic stem and progenitor cells and mesenchymal stem cells (MSC), shows promise in promoting allograft tolerance. Additionally, extracellular vesicles (EVs) derived from MSCs offer a novel avenue for extending allograft survival. This review provides a comprehensive summary of cutting-edge research on immune cell therapies, mixed chimerism therapies, and MSCs-derived EVs in the context of VCAs. Findings from preclinical and clinical studies demonstrate the tremendous potential of these alternative therapies in optimizing allograft survival in VCAs.