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Fibrinogen-Like Protein 1 Serves as an Anti-Inflammatory Agent for Collagen-Induced Arthritis Therapy in Mice. Front Immunol 2021; 12:767868. [PMID: 34975855 PMCID: PMC8716738 DOI: 10.3389/fimmu.2021.767868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 11/29/2021] [Indexed: 11/18/2022] Open
Abstract
Fibrinogen-like protein 1 (FGL1) was recently identified as a major ligand of lymphocyte-activation gene-3 (LAG-3) on activated T cells and serves as an immune suppressive molecule for regulation of immune homeostasis. However, whether FGL1 has therapeutic potential for use in the T cell-induced the autoimmune disease, rheumatoid arthritis (RA), is still unknown. Here, we attempted to evaluate the effect of FGL1 protein on arthritis progression. We also evaluated potential adverse events in a collagen-induced arthritis (CIA) mouse model. We first confirmed that soluble Fgl1 protein could specifically bind to surface Lag-3 receptor on 3T3-Lag-3 cells and further inhibit interleukin (IL-2) and interferon gamma (IFNγ) secretion from activated primary mouse T cells by 95% and 43%, respectively. Intraperitoneal administration of Fgl1 protein significantly decreased the inflammatory cytokine level (i.e., IL-1β and IL-6) in local paw tissue, and prevented joint inflammation, cellular infiltration, bone deformation and attenuated collagen-induced arthritis progression in vivo. We further demonstrated that exogenous Fgl1 does not cause obvious adverse events during treatment by monitoring body weight and liver weight, and assessing the morphology of several organs (i.e., heart, liver, spleen, lung and kidney) by pathological studies. We expect that Fgl1 protein may be suitable to serve as a potential therapeutic agent for treatment of RA or even other types of T cell-induced autoimmune or inflammatory diseases in the future.
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[Advice on the rationalized layout of outpatient clinics in a wound repair department]. ZHONGHUA SHAO SHANG ZA ZHI = ZHONGHUA SHAOSHANG ZAZHI = CHINESE JOURNAL OF BURNS 2021; 37:666-667. [PMID: 34304407 DOI: 10.3760/cma.j.cn501120-20210224-00067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
According to a document issued by the General Office of National Health Commission, "one person, one diagnosis, and one room" is required in the process of outpatient consultation. However, the patient will need to go to another room for dressing change after the doctor checks the wound if sticking to the conventional layout of current wound repair specialist outpatient clinic in hospitals and following the regulation of "separation of diagnosis and treatment". To allow a patient walking back and forth with the exposed wounds to different clinics or going to another clinic for dressing change with the original dressing reapplied to the wound is against the regulation of nosocomial infection control and the principle of sterility. To ensure that the layout of the outpatient clinic in the wound repair outpatient department not only conforms to the principle of "one person, one diagnosis, and one room", but also meets the characteristics of the diagnosis and treatment process of chronic wounds, this paper proposes the layout of "large space and small partition" in the wound repair clinic.
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Selective activation of pro-anti-IL-1β antibody enhances specificity for autoinflammatory disorder therapy. Sci Rep 2021; 11:14846. [PMID: 34290297 PMCID: PMC8295355 DOI: 10.1038/s41598-021-94298-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 07/07/2021] [Indexed: 12/26/2022] Open
Abstract
Canakinumab is a fully human monoclonal antibody that specifically neutralizes human interleukin (IL)-1β and has been approved by the US Food and Drug Administration for treating different types of autoinflammatory disorders such as cryopyrin-associated periodic syndrome, tumor necrosis factor receptor-associated periodic syndrome and systemic juvenile idiopathic arthritis. However, long-term systemic neutralization of IL-1β by Canakinumab may cause severe adverse events such as serious upper respiratory tract infections and inflammation, thereby decreasing the quality of life of patients. Here, we used an IgG1 hinge as an Ab lock to cover the IL-1β-binding site of Canakinumab by linking with matrix metalloprotease 9 (MMP-9) substrate to generate pro-Canakinumab that can be specifically activated in the inflamed regions in autoinflammatory diseases to enhance the selectivity and safety of treatment. The Ab lock significantly inhibited the IL-1β-binding by 68-fold compared with Canakinumab, and MMP-9 completely restored the IL-1β neutralizing ability of pro-Canakinumab within 60 min and blocked IL-1β-downstream signaling and IL-1β-regulated genes (i.e., IL-6). It is expected that MMP-9 cleavable and efficient Ab lock will be able to significantly enhance the selective reaction of Canakinumab at the disease site and reduce the on-target toxicities of Canakinumab during systemic circulation, thereby showing potential for development to improve the safety and quality of life of patients with autoinflammatory disorders in the future.
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Correction: Development of a structure-based computational simulation to optimize the blocking efficacy of pro-antibodies. Chem Sci 2021; 12:10395. [PMID: 34377426 PMCID: PMC8336449 DOI: 10.1039/d1sc90153b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 07/07/2021] [Indexed: 11/21/2022] Open
Abstract
Correction for ‘Development of a structure-based computational simulation to optimize the blocking efficacy of pro-antibodies’ by Bo-Cheng Huang et al., Chem. Sci., 2021, DOI: 10.1039/D1SC01748A.
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Development of a structure-based computational simulation to optimize the blocking efficacy of pro-antibodies. Chem Sci 2021; 12:9759-9769. [PMID: 34349949 PMCID: PMC8293997 DOI: 10.1039/d1sc01748a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 07/20/2021] [Accepted: 06/13/2021] [Indexed: 11/21/2022] Open
Abstract
The on-target toxicity of monoclonal antibodies (Abs) is mainly due to the fact that Abs cannot distinguish target antigens (Ags) expressed in disease regions from those in normal tissues during systemic administration. In order to overcome this issue, we “copied” an autologous Ab hinge as an “Ab lock” and “pasted” it on the binding site of the Ab by connecting a protease substrate and linker in between to generate a pro-Ab, which can be specifically activated in the disease region to enhance Ab selectivity and reduce side effects. Previously, we reported that 70% of pro-Abs can achieve more than 100-fold blocking ability compared to the parental Abs. However, 30% of pro-Abs do not have such efficient blocking ability. This is because the same Ab lock linker cannot be applied to every Ab due to the differences in the complementarity-determining region (CDR) loops. Here we designed a method which uses structure-based computational simulation (MSCS) to optimize the blocking ability of the Ab lock for all Ab drugs. MSCS can precisely adjust the amino acid composition of the linker between the Ab lock and Ab drug with the assistance of molecular simulation. We selected αPD-1, αIL-1β, αCTLA-4 and αTNFα Ab as models and attached the Ab lock with various linkers (L1 to L7) to form pro-Abs by MSCS, respectively. The resulting cover rates of the Ab lock with various linkers compared to the Ab drug were in the range 28.33–42.33%. The recombinant pro-Abs were generated by MSCS prediction in order to verify the application of molecular simulation for pro-Ab development. The binding kinetics effective concentrations (EC-50) for αPD-1 (200-250-fold), αIL-1β (152-186-fold), αCTLA-4 (68-150-fold) and αTNFα Ab (20-123-fold) were presented as the blocking ability of pro-Ab compared to the Ab drug. Further, there was a positive correlation between cover rate and blocking ability of all pro-Ab candidates. The results suggested that MSCS was able to predict the Ab lock linker most suitable for application to αPD-1, αIL-1β, αCTLA-4 and αTNFα Ab to form pro-Abs efficiently. The success of MSCS in optimizing the pro-Ab can aid the development of next-generation pro-Ab drugs to significantly improve Ab-based therapies and thus patients' quality of life. The pro-Ab blocks the Ag binding site using an Ab lock. We designed a method which uses structure-based computational simulation (MSCS) to predict the cover rate of Ab locks with various linkers and select the suitable linker for each Ab.![]()
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Enhancement of tumor tropism of mPEGylated nanoparticles by anti-mPEG bispecific antibody for ovarian cancer therapy. Sci Rep 2021; 11:7598. [PMID: 33828191 PMCID: PMC8027450 DOI: 10.1038/s41598-021-87271-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 03/22/2021] [Indexed: 12/16/2022] Open
Abstract
Ovarian cancer is highly metastatic, with a high frequency of relapse, and is the most fatal gynecologic malignancy in women worldwide. It is important to elevate the drug susceptibility and cytotoxicity of ovarian cancer cells, thereby eliminating resident cancer cells for more effective therapeutic efficacy. Here, we developed a bispecific antibody (BsAb; mPEG × HER2) that can easily provide HER2+ tumor tropism to mPEGylated liposomal doxorubicin (PLD) and further increase the drug accumulation in cancer cells via receptor-mediated endocytosis, and improve the cytotoxicity and therapeutic efficacy of HER2+ ovarian tumors. The mPEG × HER2 can simultaneously bind to mPEG molecules on the surface of PLD and HER2 antigen on the surface of ovarian cancer cells. Simply mixing the mPEG × HER2 with PLD was able to confer HER2 specificity of PLD to HER2+ ovarian cancer cells and efficiently trigger endocytosis and enhance cytotoxicity by 5.4-fold as compared to non-targeted PLD. mPEG × HER2-modified PLD was able to significantly increase the targeting and accumulation of HER2+ ovarian tumor by 220% as compared with non-targeted PLD. It could also significantly improve the anti-tumor activity of PLD (P < 0.05) with minimal obvious toxicity in a tumor-bearing mouse model. We believe that the mPEG × HER2 can significantly improve the therapeutic efficacy, potentially reduce the relapse freqency and thereby achieve good prognosis in ovarian cancer patients.
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Double attack strategy for leukemia using a pre-targeting bispecific antibody (CD20 Ab-mPEG scFv) and actively attracting PEGylated liposomal doxorubicin to enhance anti-tumor activity. J Nanobiotechnology 2021; 19:16. [PMID: 33422061 PMCID: PMC7796588 DOI: 10.1186/s12951-020-00752-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 12/08/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Tumor-targeted nanoparticles hold great promise as new tools for therapy of liquid cancers. Furthermore, the therapeutic efficacy of nanoparticles can be improved by enhancing the cancer cellular internalization. METHODS In this study, we developed a humanized bispecific antibody (BsAbs: CD20 Ab-mPEG scFv) which retains the clinical anti-CD20 whole antibody (Ofatumumab) and is fused with an anti-mPEG single chain antibody (scFv) that can target the systemic liquid tumor cells. This combination achieves the therapeutic function and simultaneously "grabs" Lipo-Dox® (PEGylated liposomal doxorubicin, PLD) to enhance the cellular internalization and anticancer activity of PLD. RESULTS We successfully constructed the CD20 Ab-mPEG scFv and proved that CD20 Ab-mPEG scFv can target CD20-expressing Raji cells and simultaneously grab PEGylated liposomal DiD increasing the internalization ability up to 60% in 24 h. We further showed that the combination of CD20 Ab-mPEG scFv and PLD successfully led to a ninefold increase in tumor cytotoxicity (LC50: 0.38 nM) compared to the CD20 Ab-DNS scFv and PLD (lC50: 3.45 nM) in vitro. Importantly, a combination of CD20 Ab-mPEG scFv and PLD had greater anti-liquid tumor efficacy (P = 0.0005) in Raji-bearing mice than CD20 Ab-DNS scFv and PLD. CONCLUSION Our results indicate that this "double-attack" strategy using CD20 Ab-mPEG scFv and PLD can retain the tumor targeting (first attack) and confer PLD tumor-selectivity (second attack) to enhance PLD internalization and improve therapeutic efficacy in liquid tumors.
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Humanized bispecific antibody (mPEG × HER2) rapidly confers PEGylated nanoparticles tumor specificity for multimodality imaging in breast cancer. J Nanobiotechnology 2020; 18:118. [PMID: 32854720 PMCID: PMC7457265 DOI: 10.1186/s12951-020-00680-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 08/17/2020] [Indexed: 02/07/2023] Open
Abstract
Background Developing a universal strategy to improve the specificity and sensitivity of PEGylated nanoaparticles (PEG-NPs) for assisting in the diagnosis of tumors is important in multimodality imaging. Here, we developed the anti-methoxypolyethylene glycol (mPEG) bispecific antibody (BsAb; mPEG × HER2), which has dual specificity for mPEG and human epidermal growth factor receptor 2 (HER2), with a diverse array of PEG-NPs to confer nanoparticles with HER2 specificity and stronger intensity. Result We used a one-step formulation to rapidly modify the nanoprobes with mPEG × HER2 and optimized the modified ratio of BsAbs on several PEG-NPs (Lipo-DiR, SPIO, Qdot and AuNP). The αHER2/PEG-NPs could specifically target MCF7/HER2 cells (HER2++) but not MCF7/neo1 cells (HER2+/−). The αHER2/Lipo-DiR and αHER2/SPIO could enhance the sensitivity of untargeted PEG-NPs on MCF7/HER2 (HER2++). In in vivo imaging, αHER2/Lipo-DiR and αHER2/SPIO increased the specific targeting and enhanced PEG-NPs accumulation at 175% and 187% on 24 h, respectively, in HER2-overexpressing tumors. Conclusion mPEG × HER2, therefore, provided a simple one-step formulation to confer HER2-specific targeting and enhanced sensitivity and contrast intensity on HER2 positive tumors for multimodality imaging. ![]()
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Bispecific antibody (HER2 × mPEG) enhances anti-cancer effects by precise targeting and accumulation of mPEGylated liposomes. Acta Biomater 2020; 111:386-397. [PMID: 32417267 DOI: 10.1016/j.actbio.2020.04.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 04/13/2020] [Accepted: 04/14/2020] [Indexed: 12/17/2022]
Abstract
Targeted antibodies and methoxy-PEGylated nanocarriers have gradually become a mainstream of cancer therapy. To increase the anti-cancer effects of targeted antibodies combined with mPEGylated liposomes (mPEG-liposomes), we describe a bispecific antibody in which an anti-methoxy-polyethylene glycol scFv (αmPEG scFv) was fused to the C-terminus of an anti-HER2 (αHER2) antibody to generate a HER2 × mPEG BsAb that retained the original efficacy of a targeted antibody while actively attracting mPEG-liposomes to accumulate at tumor sites. HER2 ×mPEG BsAb can simultaneously bind to HER2-high expressing MCF7/HER2 tumor cells and mPEG molecules on mPEG-liposomal doxorubicin (Lipo-Dox). Pre-incubation of HER2 × mPEG BsAb with cells increased the endocytosis of Lipo-DiD and enhanced the cytotoxicity of Lipo-Dox to MCF7/HER2 tumor cells. Furthermore, pre-treatment of HER2 × mPEG BsAb enhanced the tumor accumulation and retention of Lipo-DiR 2.2-fold in HER2-high expressing MCF7/HER2 tumors as compared to HER2-low expressing MCF7/neo1 tumors. Importantly, HER2 × mPEG BsAb plus Lipo-Dox significantly suppressed tumor growth as compared to control BsAb plus Lipo-Dox in MCF7/HER2 tumor-bearing mice. These results indicate that HER2 × mPEG BsAb can enhance tumor accumulation of mPEG-liposomes to improve the therapeutic efficacy of combination treatment. Anti-mPEG scFv can be fused to any kind of targeted antibody to generate BsAbs to actively attract mPEG-drugs and improve anti-cancer efficacy. STATEMENT OF SIGNIFICANCE: Antibody targeted therapy and PEGylated drugs have gradually become the mainstream of cancer therapy. To enhance the anti-cancer effects of targeted antibodies combined with PEGylated drugs is very important. To this aim, we fused an anti-PEG scFv to the C-terminal of HER2 targeted antibodies to generate a HER2×mPEG bispecific antibody (BsAb) to retain the original efficacy of targeted antibody whilst actively attract mPEG-liposomal drugs to accumulate at tumor sites. The present study demonstrates pre-treatment of HER2×mPEG BsAb can enhance tumor accumulation of mPEG-liposomal drugs to improve the therapeutic efficacy of combination treatment. Anti-mPEG scFv can be fused to any kind of targeted antibody to generate BsAbs to actively attract mPEG-drugs and improve anti-cancer efficacy.
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Non-alcoholic fatty liver disease increases the prevalence of maintenance haemodialysis in patients with chronic kidney disease. ACTA ACUST UNITED AC 2020; 121:348-351. [PMID: 32437208 DOI: 10.4149/bll_2020_055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
AIM To investigate the association between non-alcoholic fatty liver disease (NAFLD) and incidence of maintenance haemodialysis in patients with chronic kidney disease (CKD). METHODS We enrolled patients diagnosed with CKD between 2001 and 2007. The patients were categorized into two groups based on abdominal ultrasound finding, namely those with NAFLD and those without NAFLD. The disease (maintenance haemodialysis)-free survival rate was estimated using the Kaplan-Meier method. Univariate and multivariate Cox regression analyses was used to evaluate the hazard ratios of covariates for the incidence of maintenance haemodialysis. RESULTS A total of 161 patients (61 with NAFLD and 100 without NAFLD) were enrolled. The mean age was 69.3 years. The mean follow-up was 7.4 years. The patients with NAFLD had an increased incidence of maintenance haemodialysis (39.3 % vs 24.0 %; p=0.0396) and inferior disease-free survival rate (p=0.006). Furthermore, diabetes (p=0.0126) and proteinuria (p=0.0003) were identified as significant predictors of CKD progression. CONCLUSION NAFLD was associated with an increased incidence of maintenance haemodialysis and inferior disease-free survival rate. NAFLD may impair renal function and patients with renal impairment should be monitored carefully (Tab. 3, Fig. 1, Ref. 25) Keywords: non-alcoholic fatty liver disease, haemodialysis, chronic kidney disease, proteinuria.
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Abstract
Monoclonal antibodies (mAbs) are a major targeted therapy for malignancies, infectious diseases, autoimmune diseases, transplant rejection and chronic inflammatory diseases due to their antigen specificity and longer half-life than conventional drugs. However, long-term systemic antigen neutralization by mAbs may cause severe adverse events. Improving the selectivity of mAbs to distinguish target antigens at the disease site from normal healthy tissue and reducing severe adverse events caused by the mechanisms-of-action of mAbs is still a pressing need. Development of pro-antibodies (pro-Abs) by installing a protease-cleavable Ab lock is a novel and advanced recombinant Ab-based strategy that efficiently masks the antigen binding ability of mAbs in the normal state and selectively "turns on" the mAb activity when the pro-Ab reaches the proteolytic protease-overexpressed diseased tissue. In this review, we discuss the design and advantages/disadvantages of different Ab lock strategies, focusing particularly on spatial-hindrance-based and affinity peptide-based approaches. We expect that the development of different masking strategies for mAbs will benefit the local reactivity of mAbs at the disease site, increase the therapeutic efficacy and safety of long-term treatment with mAbs in chronic diseases and even permit scientists to develop Ab drugs for formerly undruggable targets and satisfy the unmet medical needs of mAb therapy.
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Specific activation of pro-Infliximab enhances selectivity and safety of rheumatoid arthritis therapy. PLoS Biol 2019; 17:e3000286. [PMID: 31194726 PMCID: PMC6563948 DOI: 10.1371/journal.pbio.3000286] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 05/10/2019] [Indexed: 12/15/2022] Open
Abstract
During rheumatoid arthritis (RA) treatment, long-term injection of antitumor necrosis factor α antibodies (anti-TNFα Abs) may induce on-target toxicities, including severe infections (tuberculosis [TB] or septic arthritis) and malignancy. Here, we used an immunoglobulin G1 (IgG1) hinge as an Ab lock to cover the TNFα-binding site of Infliximab by linking it with matrix metalloproteinase (MMP) -2/9 substrate to generate pro-Infliximab that can be specifically activated in the RA region to enhance the selectivity and safety of treatment. The Ab lock significantly inhibits the TNFα binding and reduces the anti-idiotypic (anti-Id) Ab binding to pro-Infliximab by 395-fold, 108-fold compared with Infliximab, respectively, and MMP-2/9 can completely restore the TNFα neutralizing ability of pro-Infliximab to block TNFα downstream signaling. Pro-Infliximab was only selectively activated in the disease site (mouse paws) and presented similar pharmacokinetics (PKs) and bio-distribution to Infliximab. Furthermore, pro-Infliximab not only provided equivalent therapeutic efficacy to Infliximab but also maintained mouse immunity against Listeria infection in the RA mouse model, leading to a significantly higher survival rate (71%) than that of the Infliximab treatment group (0%). The high-selectivity pro-Infliximab maintains host immunity and keeps the original therapeutic efficiency, providing a novel strategy for RA therapy. During treatment of rheumatoid arthritis, systemic administration of anti-TNFα antibodies may induce on-target toxicities, limiting their application. The incorporation of IgG1 hinge as an antibody lock generates a pro-Infliximab whose activation is specific to the disease region, enabling safer RA therapy.
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Enhanced drug internalization and therapeutic efficacy of PEGylated nanoparticles by one-step formulation with anti-mPEG bispecific antibody in intrinsic drug-resistant breast cancer. Biomater Sci 2019; 7:3404-3417. [DOI: 10.1039/c9bm00323a] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
One-step formulation of BsAb with PLD is a simple method to enhance tumor specificity, internalization and the anti-cancer activity.
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Pharmacological inhibition of bacterial β-glucuronidase prevents irinotecan-induced diarrhea without impairing its antitumor efficacy in vivo. Pharmacol Res 2019; 139:41-49. [DOI: 10.1016/j.phrs.2018.10.029] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 10/13/2018] [Accepted: 10/30/2018] [Indexed: 12/27/2022]
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SN38-loaded <100 nm targeted liposomes for improving poor solubility and minimizing burst release and toxicity: in vitro and in vivo study. Int J Nanomedicine 2018; 13:2789-2802. [PMID: 29785106 PMCID: PMC5955381 DOI: 10.2147/ijn.s158426] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Background SN38 (7-ethyl-10-hydroxycamptothecin) is a camptothecin derivative acts against various tumors. However, SN38 is hydrolyzed in the physiological environment (pH 7.4), and this instability interferes with its potential therapeutic effect. Our objective was to investigate SN38-loaded liposomes to overcome the poor solubility of SN38 and its biodistribution, which further diminish its toxicity. Materials and methods The sub-100 nm targeted liposomes was employed to deliver SN-38 and evaluate the characterization, release behaviors, cytotoxicity, in vivo pharmacokinetics and biochemical assay. Results The SN38-loaded targeted liposomes consisted of small (100.49 nm) spherical nanoparticles with negative charge (−37.93 mV) and high entrapment efficiency (92.47%). The release behavior of the SN38-loaded targeted liposomes was fitted with Higuchi kinetics (R2=0.9860). Free SN38 presented initial burst release. The IC50 for the SN38-loaded targeted liposomes (0.11 μM) was significantly lower than for the SN38 solution (0.37 μM) in the MCF7 cell line (P<0.01). Confocal laser scanning microscopy also confirmed highly efficient accumulation in the MCF7 cells. Pharmacokinetics demonstrated that the SN38-loaded targeted liposomes had a slightly increased half-life and mean residence time and decreased area under the concentration–time curve and maximum concentration. The results suggested that retention was achieved while the exposure of SN38 was significantly decreased. A noninvasive in vivo imaging system also showed that the targeted liposomes selectively targeted MCF7 tumors. In vivo toxicity data demonstrated that the decrease in platelets was significantly improved by SN38-loaded targeted liposomes, and diarrhea was not observed in BALB/c mice. Conclusion In summary, SN38-loaded targeted liposomes could be a good candidate for application in human breast cancer.
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Specific Inhibition of Bacterial β-Glucuronidase by Pyrazolo[4,3-c]quinoline Derivatives via a pH-Dependent Manner To Suppress Chemotherapy-Induced Intestinal Toxicity. J Med Chem 2017; 60:9222-9238. [DOI: 10.1021/acs.jmedchem.7b00963] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Selective antibody activation through protease-activated pro-antibodies that mask binding sites with inhibitory domains. Sci Rep 2017; 7:11587. [PMID: 28912497 PMCID: PMC5599682 DOI: 10.1038/s41598-017-11886-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 08/31/2017] [Indexed: 12/16/2022] Open
Abstract
Systemic injection of therapeutic antibodies may cause serious adverse effects due to on-target toxicity to the antigens expressed in normal tissues. To improve the targeting selectivity to the region of disease sites, we developed protease-activated pro-antibodies by masking the binding sites of antibodies with inhibitory domains that can be removed by proteases that are highly expressed at the disease sites. The latency-associated peptide (LAP), C2b or CBa of complement factor 2/B were linked, through a substrate peptide of matrix metalloproteinase-2 (MMP-2), to an anti-epidermal growth factor receptor (EGFR) antibody and an anti-tumor necrosis factor-α (TNF-α) antibody. Results showed that all the inhibitory domains could be removed by MMP-2 to restore the binding activities of the antibodies. LAP substantially reduced (53.8%) the binding activity of the anti-EGFR antibody on EGFR-expressing cells, whereas C2b and CBa were ineffective (21% and 9.3% reduction, respectively). Similarly, LAP also blocked 53.9% of the binding activity of the anti-TNF-α antibody. Finally, molecular dynamic simulation showed that the masking efficiency of LAP, C2b and CBa was 33.7%, 10.3% and −5.4%, respectively, over the binding sites of the antibodies. This strategy may aid in designing new protease-activated pro-antibodies that attain high therapeutic potency yet reduced systemic on-target toxicity.
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Effects of mutant TDP-43 on the Nrf2/ARE pathway and protein expression of MafK and JDP2 in NSC-34 cells. GENETICS AND MOLECULAR RESEARCH 2017; 16:gmr-16-02-gmr.16029638. [PMID: 28510254 DOI: 10.4238/gmr16029638] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that affects motor neurons and lacks an effective treatment. The disease pathogenesis has not been clarified at present. Pathological transactive response DNA-binding protein 43 (TDP-43) plays an important role in the pathogenesis of ALS. Nuclear translocation of nuclear factor erythroid 2 (NF-E2)-related factor 2 (Nrf2) is found in a mutant TDP-43 transgenic cell model, but its downstream antioxidant enzyme expression is decreased. To elucidate the specific mechanism of Nrf2/ARE (antioxidant responsive element) signaling dysfunction, we constructed an ALS cell model with human mutant TDP-43 using the NSC-34 cell line to evaluate the impact of the TDP-43 mutation on the Nrf2/ARE pathway. We found the nuclear translocation of Nrf2, but the expression of total Nrf2, cytoplasmic Nrf2, and downstream phase II detoxifying enzyme (NQO1) was decreased in NSC-34 cells transfected with the TDP-43-M337V plasmid. Besides, TDP-43-M337V plasmid-transfected NSC-34 cells were rounded with reduced neurites, shortened axons, increased levels of intracellular lipid peroxidation products, and decreased viability, which suggests that the TDP-43-M337V plasmid weakened the antioxidant capacity of NSC-34 cells and increased their susceptibility to oxidative damage. We further showed that expression of the MafK protein and the Jun dimerization protein 2 (JDP2) was reduced in TDP-43-M337V plasmid-transfected NSC-34 cells, which might cause accumulation of Nrf2 in nuclei but a decrease in NQO1 expression. Taken together, our results confirmed that TDP-43-M337V impaired the Nrf2/ARE pathway by reducing the expression of MafK and JDP2 proteins, and provided information for further research on the molecular mechanisms of TDP-43-M337V in ALS.
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Optimization of an Anti-poly(ethylene glycol) (anti-PEG) Cell-Based Capture System To Quantify PEG and PEGylated Molecules. Anal Chem 2016; 88:12371-12379. [DOI: 10.1021/acs.analchem.6b03614] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Modified nanoprecipitation method for polysulfone nanoparticles preparation. SOFT MATTER 2014; 10:3414-20. [PMID: 24643577 DOI: 10.1039/c3sm53003e] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Towards developing a more universal and productive nanoprecipitation processes, we focus on the preparation of polysulfone (PSF) nanoparticles through instantaneous solvent displacement in a metal membrane contactor between dimethylformamide (DMF) and water. In the original nanoprecipitation process, cubic nuclei can form instantaneously, but slow growth and aggregation have intensive interactions. Moreover, the reservation of DMF may enhance the adhesive effect between polymeric particles, causing severe particle aggregation. To overcome this difficulty, a modified nanoprecipitation method appending a quenching step was proposed. The well-dispersed PSF nanoparticles are successfully obtained when ethyl acetate is introduced. In this way, DMF can be extracted from water solution, thus facilitating the precipitating of PSF. Furthermore, selecting water as the continuous fluid, the particle size can be adjusted simply by tuning the operating parameters, including the PSF concentration in the dispersed fluid and the ratio of two feeds. Compared with previous reports on the continuous nanoprecipitation process for polymeric nanoparticles preparation, this work shows advantages including expanding the adaptability to more functional polymers, providing better flexibility on process or product development independent of the use of surfactant, and presenting a high throughput and easy-to-scale-up equipment platform.
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Retinoblastoma protein-interacting zinc-finger gene 1 (RIZ1) dysregulation in human malignant meningiomas. Oncogene 2012; 32:1216-22. [PMID: 22614009 DOI: 10.1038/onc.2012.155] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Retinoblastoma protein-interacting zinc-finger gene 1 (RIZ1) expression is often silenced in many types of human tumors. However, the relationship between RIZ1 expression and malignant meningiomas remains unclear. Here we have found for the first time that the expression of RIZ1 genes are associated with meningiomas progression through extensive analyses of Affymetrix GeneChip microarray data. Further validation methods for gene expression included quantitative PCR (qPCR), western blot and immunohistochemistry analysis, and these methods confirmed that RIZ1 is significantly downregulated in malignant meningioma tissues, as compared with benign meningiomas. In addition, malignant meningioma cells were stably transfected with ectogenic RIZ1 using Lentivirus-mediated transfection, and the transfections were followed by an in vitro 5-bromo-2-deoxyuridin incorporation assay, colony formation assay, cell cycle analysis, invasive analysis, apoptotic assay and western blot analysis. Our results demonstrate that the forced expression of RIZ1 in a malignant meningioma cell line inhibited cellular proliferation and arrested the cells in the G2/M phase of the cell cycle. We also confirmed that overexpression of RIZ1 may induce apoptosis of malignant meningioma cells. Furthermore, RIZ1 overexpression in malignant meningioma cells was associated with the downregulation of c-myc expression. These results from our study indicate that RIZ1 expression is significantly downregulated as the formation of meningiomas progressed, and suggest that RIZ1 may represent a promising candidate tumor suppressor gene that contributes to malignant meningiomas.
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Solitary Intracranial Plasmacytoma Located in the Spheno-Clival Region Mimicking Chordoma: A Case Report. J Int Med Res 2010; 38:1868-75. [PMID: 21309504 DOI: 10.1177/147323001003800535] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Solitary intracranial plasmacytoma (SIP) is very rare. This case report presents serial findings of SIP located in the spheno-clival region in a 54-year old female who presented with an inferior hemianopia in the right eye and an enlarged physiological blind spot in both eyes. Based on the initial diagnosis of a spheno-clival region chordoma, the tumour was partially resected by the nasal–sphenoidal sinus approach. Subsequently, the correct diagnosis of SIP was made based on the pathology and immunohistochemical staining of the tumour. The patient was treated using a whole skull-base radiation therapy protocol with 45 Gy and she was in good physical condition during the subsequent 22 months. The findings of a series of similar case reports documenting SIP in 20 cases published from 1976 to 2008 are also reviewed. Based on these case reports, the key features of SIP, including their clinical manifestations, clinical imaging characteristics, treatment and prognosis, are described.
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Tailoring of silver wires and their performance as transparent conductive coatings. NANOTECHNOLOGY 2010; 21:215707. [PMID: 20431210 DOI: 10.1088/0957-4484/21/21/215707] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A feasible way to manipulate the scales of Ag wires through the polyol process is presented. By adjusting the amounts of either Pd or Ag precursor used in this process, we demonstrated the ability to control the scale of the wires. The presence of Pd ultrafine particles reduced by EG in advance served as the nuclei for inducing the subsequent formation of Ag wires, and the diameter of the resulting wires was observed to be inversely proportional to the quantity of Pd added. Further, the wire length was demonstrated to be proportional to and highly correlated with the total amount of Ag added, by a linear relationship. A glass plate coated with Ag wire film by the spray method is shown to be both transparent and conductive. The effect of scaling the wires on their performance is also discussed.
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Rosette-forming glioneuronal tumour of the fourth ventricle with previous intratumoural haemorrhage: case report and review of the literature. J Int Med Res 2009; 37:958-66. [PMID: 19589282 DOI: 10.1177/147323000903700342] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The case is reported of a rosette-forming glioneuronal tumour of the fourth ventricle (RGTFV) in a 27-year-old male. Symptoms included headache, severe vomiting and clumsy walking that had progressively worsened over 14 days. Computed tomography and magnetic resonance imaging indicated a 3.0 x 2.5 x 2.0 cm solid-cystic mass in the fourth ventricle and obstructive hydrocephalus. The tumour showed evidence of previous intra-tumour haemorrhage, with heterogeneous enhancement after contrast administration. Complete excision of the lesion was performed. Signs of previous intra-tumoural haemorrhage were seen intra-operatively. The detailed clinical, radiological and pathological features in this patient are described and compared with existing literature on this type of tumour. Despite benign histological features and a reported favourable post-operative course, there is still limited clinical experience with this type of tumour, however intratumoural haemorrhage may result in morbidity and mortality. This report will help provide better characterization of this entity, improving the diagnosis and potentially reducing mortality in RGTFV.
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Determination of dynamic interfacial tension and its effect on droplet formation in the T-shaped microdispersion process. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:2153-2158. [PMID: 19152256 DOI: 10.1021/la803049s] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Interfacial tension is an important physical property affecting the droplet formation process in microfluidic devices. This work presents the variation of dynamic interfacial tension caused by slow adsorption of surfactant, as well as its influence on the liquid/liquid microdispersion process in a T-shaped microchannel. Using hexane/water-Tween 20 as the working system, it was observed that the droplet size changed with the variation of surfactant concentration when the concentration of Tween 20 was lower than 10 mmol/L, but hardly changed at higher concentrations, which was caused by the unsaturated adsorption and saturated adsorption of surfactant, respectively. The saturated interfacial tension was measured with an interfacial tension meter, and the relationship between the interfacial tension and the droplet diameter was established. Accordingly, the dynamic interfacial tension with unsaturated adsorption of surfactant was determined. The main factors affecting the dynamic interfacial tension were discussed, and a semiempirical equation was established to characterize those effects.
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Safrole-Induced Ca2+Mobilization and Cytotoxicity in Human PC3 Prostate Cancer Cells. J Recept Signal Transduct Res 2008; 26:199-212. [PMID: 16777715 DOI: 10.1080/10799890600662595] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The effect of the carcinogen safrole on intracellular Ca2+ mobilization and on viability of human PC3 prostate cancer cells was examined. Cytosolic free Ca2+ levels ([Ca2+]i) were measured by using fura-2 as a probe. Safrole at concentrations above 10 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 350 microM. The Ca2+ signal was reduced by more than half after removing extracellular Ca2+ but was unaffected by nifedipine, nicardipine, nimodipine, diltiazem, or verapamil. In Ca2+-free medium, after treatment with 650 microM safrole, 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) failed to release Ca2+. Neither inhibition of phospholipase C with U73122 nor modulation of protein kinase C activity affected safrole-induced Ca2+ release. Overnight incubation with 0.65-65 microM safrole did not affect cell viability, but incubation with 325-625 microM safrole decreased viability. Collectively, the data suggest that in PC3 cells, safrole induced a [Ca2+]i increase by causing Ca2+ release from the endoplasmic reticulum in a phospholipase C- and protein kinase C-independent fashion, and by inducing Ca2+ influx. Safrole can decrease cell viability in a concentration-dependent manner.
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Melittin-induced [Ca2+]i increases and subsequent death in canine renal tubular cells. Hum Exp Toxicol 2008; 27:417-24. [DOI: 10.1177/0960327108094606] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The effect of melittin on cytosolic free Ca2+ concentration ([Ca2+]i) and viability is largely unknown. This study examined whether melittin alters Ca2+ levels and causes Ca2+-dependent cell death in Madin-Darby canine kidney (MDCK) cells. [Ca2+]i and cell death were measured using the fluorescent dyes fura-2 and WST-1 respectively. Melittin at concentrations above 0.5 μM increased [Ca2+]i in a concentration-dependent manner. The Ca2+ signal was reduced by 75% by removing extracellular Ca2+. The melittin-induced Ca2+ influx was also implicated by melittin-caused Mn2+ influx. After pretreatment with 1 μM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), melittin-induced Ca2+ release was inhibited; and conversely, melittin pretreatment abolished thapsigargin-induced Ca2+ release. At concentrations of 0.5–20 μM, melittin killed cells in a concentration-dependent manner. The cytotoxic effect of 0.5 μM melittin was nearly completely reversed by prechelating cytosolic Ca2+ with BAPTA. Melittin at 0.5–2 μM caused apoptosis as assessed by flow cytometry of propidium iodide staining. Collectively, in MDCK cells, melittin induced a [Ca2+]i rise by causing Ca2+ release from endoplasmic reticulum and Ca2+ influx from extracellular space. Furthermore, melittin can cause Ca2+-dependent cytotoxicity in a concentration-dependent manner.
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Abstract
BACKGROUND Dentatorubropallidoluysian atrophy (DRPLA) is a rare, autosomal dominant neurodegenerative disease characterized by a range of clinical manifestations, including cerebellar ataxia, epilepsy, myoclonus, choreoathetosis, and dementia. Outside the Japanese population, the prevalence is extremely low worldwide. The reason for different ethnic prevalences of DRPLA is unclear. A previous assumption was that large normal alleles contribute to generation of expanded alleles and the relative frequencies of DRPLA. OBJECTIVES To describe the clinical, radiological, and genetic features of the first reported Chinese family with DRPLA, to our knowledge, and to compare the size distribution of normal alleles at the DRPLA locus in healthy Chinese individuals with that of other ethnic groups. PATIENTS AND METHODS Of 80 Chinese kindreds with autosomally dominant spinocerebellar ataxias, 1 pedigree with 2 affected patients was found by polymerase chain reaction to carry the characteristic DRPLA mutation. The allele frequencies of different CAG repeat lengths at the DRPLA locus in 225 healthy Chinese individuals were also analyzed and compared with Japanese, white, and African American distributions. RESULTS The clinical presentations of the 2 Chinese patients affected with DRPLA are similar to those described in Japanese patients, except that the affected father exhibited myoclonus but not chorea. Although the normal DRPLA allele size is distributed similarly in Chinese and Japanese populations, DRPLA in Chinese individuals is rare. Thus far, to our knowledge, only 1 intermediate-sized allele containing more than 30 CAG repeats has been reported among healthy Chinese individuals, in contrast to 3 among Japanese populations. CONCLUSION The ethnic prevalence of DRPLA seems to be correlated with the prevalence of intermediate-sized alleles in individual populations.
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Abstract
A 10-year longitudinal follow-up study of hearing was conducted in patients with nasopharyngeal carcinoma (NPC) in order to elucidate the mechanism of hearing loss in irradiated ears. Ten NPC patients were subjected to a battery of audiological tests before irradiation and 6 months, 5 years, and 10 years after irradiation. The tests included pure tone audiometry, tympanometry, eustachian tube function testing, and myringotomy to confirm middle ear effusion. The prevalences of otitis media with effusion (OME) were 25%, 25%, 40%, and 25% at the 4 testing periods described above, respectively. The prevalences of chronic otitis media were 0%, 0%, 15%, and 25%, respectively. In myringotomized ears (n = 17), the mean hearing levels for both air conduction and bone conduction were preserved from the preirradiation period to 10 years after irradiation. In contrast, in grommeted ears (n = 3), the mean hearing levels for both air conduction and bone conduction deteriorated progressively from the preirradiation period to 10 years after irradiation. We conclude that hearing can be preserved in NPC patients 10 years after irradiation if middle ear inflammation is well controlled. We do not recommend grommet insertion in irradiated NPC patients with OME, as it may result in persistent otorrhea and hearing deterioration.
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Abstract
The purpose of this study was to evaluate the effects of various surface treatments on the bond strength at the In-Ceram/resin composite interface. Ninety-eight In-Ceram specimens were divided into seven groups and exposed to various surface treatments as follows: (A) control (B) saliva contamination (C) saliva contamination plus aluminum oxide sandblasting (D) glove powder contamination (E) glove powder contamination plus aluminum oxide sandblasting (F) rough aluminum oxide sandblasting and (G) excess glass infiltration. A resin composite cylinder was cemented to each In-Ceram specimen with Panavia 21 resin luting cement. Half of the cemented specimens in each group were stored in water for 24 h, and the other half were stored in water for 2 weeks and then were thermo-cycled for 2000 cycles. Shear bond strengths (SBS) of seven specimens in each subgroup were determined and analysed using analysis of variance (ANOVA) and Tukey HSD test as well as Student's t-test. Scanning electronic microscopy was used to identify the type of bond failure. Shear bond strength was significantly decreased by saliva and glove powder contaminations (P < 0.05). Sandblasting treatment did not improve the saliva-contaminated specimens. However, the glove powder plus sandblasting group showed no significant difference in SBS compared with the control group. There was no significant difference in SBS between the excess glass-infiltrating group and the control group. The SBS was significantly decreased by rough aluminum oxide sandblasting (P < 0.05). The SBS values of groups without thermocycling were significantly greater than those of groups with thermocycling (P < 0.05). There were no significant differences among SBS values of the seven groups with thermocycling. Combined cohesive and adhesive bond failures were seen in every group. Various surface treatments or contaminants may significantly influence the bond strength of In-Ceram restorative in clinical use.
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Lipoma arborescens of the knee: a case report. J Formos Med Assoc 2001; 100:412-5. [PMID: 11480252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
Lipoma arborescens is a rare intraarticular lesion of unknown etiology. We describe the radiographic, computerized tomographic, and magnetic resonance (MR) imaging characteristics of lipoma arborescens in a 17-year-old boy presenting with chronic painful swollen knee. Histologic examination after surgical synovectomy confirmed the diagnosis of lipoma arborescens. The fatty nature and frond-like appearance of this lesion can be demonstrated on imaging studies, especially MR imaging. Open synovectomy is curative in most cases. Although lipoma arborescens is rare, it is important to recognize and differentiate it from other synovial lesions by MR imaging.
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Abstract
Community-based services are being developed as mental health services. The purpose of this study was to examine the effect between home care and half-way house services on patients with schizophrenia. The design was quasi-experimental and used repeated measurements. There were 60 subjects, 37 receiving home care and 23 receiving half-way house care which were affiliated with one general hospital in the south of Taiwan. Of the 60 chronic schizophrenic patients, there were 34 males and 26 females with an average age of 34 years. The Quality of Life Scale was applied to measure each patient four times, at an interval of two months. These follow-up data were analyzed by Generalized Estimating Equation-I (GEE-I) because repeated observations on an individual may be correlated. The result showed that the total QOL in patients receiving home care programs was significantly higher than those receiving half-way house service. The total scores of QOL in patients under half-way house and home care services did not show secular change. The patients under home care program showed a somewhat improvement for a short period of time. However, as time went on, the patients showed no obvious improvement in their life quality. The dimensions of independence and social activity in QOL also showed significantly different between these two groups. The results may provide guides on designing programs and activities for the chronic mental patients. However, the best decision to apply which program for patients need continouous and comprehensive assessment.
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Abstract
On-line carcass inspection of chickens in the United States is currently done using visual (organoleptic) methods. Inspectors from the USDA Food Safety and Inspection Service (FSIS) inspect the viscera and carcass and, for older birds, the heads using a sequence of observations and palpations at a postmortem inspection station. The streamlined inspection system (SIS) and the new line speed inspection system (NELS) are the most prevalent visual inspection methods. The former has a line speed of 70 birds/min with two inspectors per line, and the latter has a line speed of 91 birds/min requiring three inspectors per line. Both inspection methods are labor intensive and prone to human error. In addition, the speed of the slaughter line is dictated by the number of birds per minute that can be inspected by FSIS inspectors. Ninety-one birds/min is currently the maximum visual inspection line speed allowed under current Federal regulations. This study evaluates the economic benefits of using automated inspection in place of visual inspection from the perspective of both the slaughter plant and FSIS. The results indicate that FSIS and slaughter plants would gain economic benefits by using automated inspection in place of visual inspection. The economic benefits to FSIS would accrue from labor savings, whereas the economic benefits to slaughter plants would accrue primarily from increased throughput from faster inspection line speeds.
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The race of the millennium: CD-ROM versus the textbook. CMAJ 1999; 161:1527-8. [PMID: 10624411 PMCID: PMC1230869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
OBJECTIVE To determine whether CD-ROMs are as fast as everyone thinks they are. METHODS A grand contest between 2 textbooks and their electronic versions, held with the help of 10 victims. RESULTS AND INTERPRETATION We can't be expected to tell you that now. You'll have to read the paper.
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Abstract
For patients with differentiated thyroid carcinoma, the appropriate degree of TSH suppression by levothyroxine (L-T4) is still unknown. To find the target level of TSH suppression, we analyzed the relationship between the degree of TSH suppression determined by third generation assay and thyroglobulin (Tg) response during the titration of the dosage of L-T4. Ninety-two patients with differentiated thyroid carcinoma (19 males and 73 females; age, 40.5+/-13.5, mean +/- SD) were included. All of the recruited patients had near-total thyroidectomy, 30-150 mCi 131I thyroid ablation, and negative Tg autoantibodies. They were classified into 3 groups. Group A was composed of 25 patients with local or distant relapse. Group B was composed of 12 patients without clinically detectable relapse, but Tg levels either above 2 ng/mL under L-T4 suppression or above 3 ng/mL off L-T4 therapy. Group C included 55 patients who had no active disease and Tg levels below 2 and 3 ng/mL during and off L-T4 suppression, respectively. Serum TSH and Tg were measured simultaneously at the end of 8-12 weeks of a certain dose of L-T4 therapy during dosage titration and also after withdrawal of L-T4 for 4-6 weeks for the total body scan. Wilcoxon signed ranks test was used to compare paired samples of Tg, and Spearman rank correlation was used to determine the correlation of relative changes in TSH to changes in Tg calculated by individual. The results showed that 1) Tg levels were significantly higher during the period off L-T4 therapy than on L-T4, therapy in all 3 groups (P < 0.01); 2) during L-T4, therapy, within the same treatment course, mean Tg levels were higher when TSH levels were normal than when TSH levels were suppressed, statistically significant in group A (P = 0.001), nonsignificant in group B (P = 0.09), and nonsignificant in group C (P = 0.30); and 3) when TSH was suppressed below normal, there was no correlation between the relative changes in TSH and Tg by individual in all 3 groups (P > 0.05). The data suggest a stratified postoperative thyroid hormone management of patients with differentiated thyroid carcinoma. TSH should be lowered to below normal in patients with active disease. If patients are clinically disease free with Tg levels below 2 ng/mL, TSH can be kept within the normal range. For the most controversial group B patients, it is recommended that the TSH be suppressed and be closely followed up.
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Corticotropin releasing factor and substance P mediate the nucleus amygdaloideus centralis-nucleus ventromedialis-nucleus dorsomedialis pressor system. Brain Res 1999; 842:392-8. [PMID: 10526135 DOI: 10.1016/s0006-8993(99)01862-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Prolonged emotional stress is an important factor in the development of neurogenic hypertension, but its mechanism is still unclear. The purpose of the present study is to analyze the possible neural basis of hypertension induced by prolonged emotional stress. In the brain many nuclei are involved in emotional reaction, stress or defense response; among them the nucleus amygdaloideus centralis (AC) is the most important one which widely connects with other nuclei controlling emotion and stress, such as nucleus ventromedialis (NVM), nucleus dorsomedialis (NDM), nucleus paraventricularis (NPV) etc. These nuclei contain corticotropin releasing factor (CRF)- and substance P (SP)-immunoreactive cell bodies, nerve terminals and corresponding receptors. Our previous and present studies showed that microinjection of CRF or SP into these nuclei induced pressor responses. These data imply that excitation of the AC can activate many nuclei controlling emotion and stress via CRF and SP, and excessive activities of these nuclei may be the neural basis of hypertension induced by prolonged emotional stress. The present study revealed that (1) the AC pressor response to glutamate (Glu) could be reduced by preinjection of CRF antagonist (alpha-Helical CRF[9-41] or SP antagonist ([D-Pro(2), D-Phe(7), D-Trp(9)]-substance P) into bilateral NVM, (2) the NVM pressor response to Glu were decreased by pretreatment of the NDM with CRF- or SP-antagonist, (3) the AC-, NVM- or NDM-pressor responses were all attenuated by preinjection of CRF- or SP-antagonist into bilateral NPV or rostral ventrolateral medulla (RVL). The results indicate that excitation of the AC can indirectly activate the NPV and RVL to evoke pressor response via the NVM-NDM, CRF and SP are transmitters in each connection of this pathway; this is one component of the mechanism underlying the AC pressor response. Taken together with the findings of our previous studies, it provides neurophysiological basis for the above-mentioned implications.
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Abstract
A case of acute progressive disseminated histoplasmosis complicated with hypercalcemia is reported and the literature is reviewed. This and the previously reported cases imply that physicians should have a higher index of suspicion for this infection and the probable underlying diseases resulting from impaired cellular-mediated immunity when encountering patients with hypercalcaemia.
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Abstract
OBJECTIVE To define the imaging characteristics of intra-articular tophi of the knee. DESIGN AND PATIENTS Twelve patients with intra-articular tophi in the knee were studied with routine MR imaging, gadolinium (Gd)-enhanced MR imaging, and CT over a 4-year period. There were 11 men and one woman, 25-82 years of age (mean age 48 years). Four patients did not have a documented history of gout at the time of the MR examination. The diagnosis of intra-articular tophi was provided by arthroscopy and histological examination (5 patients), by microscopic study of joint fluid (5 patients), or by characteristic clinical, laboratory and imaging findings (2 patients). RESULTS In 15 MR examinations the tophi were located purely intra-articularly in 10 knees. In the remaining five MR studies, periarticular soft tissues or bone, or both, were involved. All the intra-articular tophi manifested low to intermediate signal intensity on both T1- and T2-weighted images. All five Gd-enhanced MR examinations demonstrated a heterogeneous peripheral enhancement. All 10 CT scans showed varying degrees of stippled calcifications within the tophi. The nature of the calcifications was confirmed on histological examination in three patients. CONCLUSION Presenting clinical manifestations of gout may relate to intra-articular tophaceous deposits. Such deposits present as masses on MR images with low to intermediate signal intensity on both T1- and T2-weighted images and a characteristic enhancement pattern following intravenous Gd administration. These features relate primarily to internal calcifications, which are most evident on CT images. MR evaluation (including Gd administration) supplemented, in some cases, with CT scanning allows accurate diagnosis of intra-articular tophaceous deposits.
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Co-regulation of tissue-specific alternative human carnitine palmitoyltransferase Ibeta gene promoters by fatty acid enzyme substrate. J Biol Chem 1998; 273:32901-9. [PMID: 9830040 DOI: 10.1074/jbc.273.49.32901] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Carnitine palmitoyltransferase I (CPT-I) catalyzes the rate-determining step in mitochondrial fatty acid beta-oxidation. CPT-I has two structural genes (alpha and beta) that are differentially expressed among tissues. Our CPT-Ibeta isolates from a human cardiac cDNA library contained two different extreme 5'-sequences derived from short alternative first untranslated exons that utilize a common splice acceptor site in exon 2. Primer extension identified single dominant start sites for each transcript, and ribonuclease protection assays showed the presence of one 5'-exon in liver, muscle, and heart mRNAs, indicating that the cognate promoter U (upstream/ubiquitous) is active in each of these tissues. By contrast, mRNAs containing the alternative 5'-exon were present only in muscle and heart, indicating a muscle-specific promoter M (muscle). CPT-Ibeta mRNA levels increased markedly in tissues of fasted rats, when circulating free fatty acid concentrations are elevated. Using CPT-Ibeta promoter/reporter transient transfection of murine C2C12 myotubes and HepG2 hepatocytes, fatty acids were found to increase promoter activity in a peroxisome proliferator-activated receptor alpha (PPARalpha)-dependent fashion. A promoter fatty acid response element (FARE) was mapped, mutation of which ablated fatty acid-mediated production of both transcripts. PPARalpha/retinoid X receptor alpha formed specific complexes with oligonucleotides containing the FARE, and anti-PPARalpha antibody shifted nuclear protein-DNA complexes, confirming the role of this factor in regulating the expression of this critical metabolic enzyme gene. The constitutive repressor chicken ovalbumin upstream promoter transcription factor competitively binds at the FARE and modulates fatty acid induction of the promoters.
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Outcome of Graves' disease after antithyroid drug treatment in Taiwan. J Formos Med Assoc 1998; 97:619-25. [PMID: 9795530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The outcome of Graves' disease after treatment with antithyroid drugs (ATDs) varies widely among countries, and large-scale studies in Asia are rare. We investigated the associations of various clinical and laboratory features with the outcome of ATD therapy for Graves' disease in Taiwan. A total of 210 patients (177 women, 33 men; mean +/- SD age, 41.7 +/- 15.1 yr) treated with ATD in Taiwan were included. ATD therapy started with methimazole 30 mg daily or propylthiouracil 300 mg daily and was continued until a euthyroid state was achieved. Afterwards, 154 patients received a maintenance dose of ATD alone, while 56 patients received a combination of an ATD and thyroxine (L-T4). Patients were considered to be in remission if they remained in a euthyroid state for more than 2 years after drug withdrawal. The mean follow-up periods were 45.0 +/- 20.9 months for patients with remission and 30.4 +/- 19.8 months for those with relapse. Relapse occurred in 126 (60%) patients during the follow-up period, within 3 months after drug withdrawal in 47 (37%), and within 6 months in 60 (46%). The relapse rate was 100% among patients with two or more previous relapses. Patients with a second occurrence had a higher relapse rate than those with a first occurrence (84% vs 43%). Past history of recurrence, goiter size, thyroid-stimulating hormone level and thyrotropin-binding inhibition immunoglobulin activity at the end of ATD treatment were independently associated with relapse. Prolonged duration of treatment did not yield better results in patients with larger goiters or a history of recurrence, or both. Combination therapy with L-T4 yielded similar results to those achieved with ATD treatment alone. In conclusion, the relapse rate of Graves' disease after ATD treatment in Taiwanese patients was high, especially in those with a history of recurrence. The treatment duration and drug regimen did not affect the outcome.
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Expression of novel isoforms of carnitine palmitoyltransferase I (CPT-1) generated by alternative splicing of the CPT-ibeta gene. Biochem J 1998; 334 ( Pt 1):225-31. [PMID: 9693124 PMCID: PMC1219683 DOI: 10.1042/bj3340225] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Carnitine palmitoyltransferase I (CPT-I) catalyses the rate-determining step in mitochondrial fatty acid beta-oxidation. The enzyme has two cognate structural genes that are preferentially expressed in liver (alpha) or fat and muscle (beta). We hypothesized the existence of additional isoforms in heart to account for unique kinetic characteristics of enzyme activity in this tissue. Hybridization and PCR screening of a human cardiac cDNA library revealed the expression of two novel CPT-I isoforms generated by alternative splicing of the CPT-Ibeta transcript, in addition to the beta and alpha cDNA species previously described. Ribonuclease protection and reverse transcriptase-mediated PCR assays confirmed the presence of mRNA species of each splicing variant in heart, skeletal muscle and liver, with differing relative concentrations in the tissues. The novel splicing variants omit exons or utilize a cryptic splice donor site within an exon. Deduced polypeptide sequences of the novel enzymes include omissions in the region of putative membrane-spanning and malonyl-CoA regulatory domains compared with the previously described CPT-Is, implying that the encoded enzymes will exhibit unique features with respect to outer mitochondrial membrane topology and response to physiological and pharmacological inhibitors.
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Abstract
Carnitine palmitoyltransferase I (CPT-I) catalyzes the rate-determining step in mitochondrial fatty acid beta-oxidation. The enzyme has two cognate structural genes (alpha and beta) that are differentially expressed in tissues. We show multiple mature mRNAs in rat heart derived from alternative splicing of CPT-Ibeta transcripts. Two novel messages are deleted for regions of the previously described mRNA that encode membrane-spanning and regulatory domains, suggesting that the cognate isozymes will exhibit unique kinetic characteristics.
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Endobronchial metastasis from an occult papillary thyroid carcinoma: a case report. CHANGGENG YI XUE ZA ZHI 1998; 21:200-5. [PMID: 9729656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
It is well known that occult papillary thyroid cancers can result in regional lymph node metastasis. However, this small, clinically undetectable cancer rarely causes distant metastasis; moreover, an endobronchial presentation has not been described previously. We report on a 48-year-old man who experienced hemoptysis. A fiberoptic bronchoscopic biopsy established the diagnosis of endobronchial metastasis in the absence of clinically apparent thyroid cancer. After the patient was treated with a total thyroidectomy and radioactive iodine (131I), a whole body radioiodine scan revealed no evidence of distant functioning metastasis. A histological evaluation of the thyroid gland showed the presence of a 0.2 x 0.2 x 0.2 cm nodule in the right lobe. A left pneumonectomy was undertaken to treat the distant metastasis of the disease. Since most papillary thyroid carcinomas are curable, an aggressive surgical approach to the solitary metastasis is indicated.
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[Role of substance P in pressor response of central amygdaloid nucleus to glutamate]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 1997; 49:419-26. [PMID: 9812874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Substance P (SP)-immunoreactive cells and the axon terminals are widely distributed in the central amygdaloid nucleus (AC) and its important projection areas. The present study showed that (1) Excitation of the AC by glutamate (Glu) or injection of SP into the AC projection areas: locus coeruleus (LC), nucleus parabrachialis (NPB), periaqueductal gray matter (PAG) or lateral hypothalamus-perifornical region (LH/PF), all elicited pressor response. (2) Preinjection of DPDPDT (a SP antagonist) into bilateral LC, NPB, PAG or LH/PF could attenuate the AC pressor response to Glu. (3) Intra-RVLM (rostral ventrolateral medulla) preinjection of either phentolamine, propranolol or atropine (but not GDEE, a Glu antagonist) could also reduce the AC pressor response. Taken together with our previous findings that the alpha-, beta-, M-receptors in RVLM mediated the pressor response to LC excitation, alpha-receptors mediated the NPB pressor response, alpha- and beta-receptors mediated the PAG pressor response; these results indicate that the SPergic projections of the AC not only directly act upon the brainstem pressor areas (LC, NPB, PAG)-RVLM system, but also indirectly via the LH/PF act upon the brainstem pressor areas-RVLM system to induce the pressor response.
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Abstract
The purpose of the study was to examine the relationship between the hormonal and psychological responses of young men about to engage in a potentially life-threatening event. Subjects were recruited to take their first skydiving jump. The scores on questionnaires designed to assess anxiety were not significantly increased at 0800 h on the morning before the jump by comparison with scores obtained from the same subjects 3-5 days previously. However, a psychological instrument for rating of events indicated significantly increased intensity, and sympathetic nervous system activity, as measured by the salivary amylase response, was increased over self-control values. Salivary cortisol and testosterone levels were significantly lower on the morning of the jump than self-control values and values in control subjects determined at the same time of day. However, plasma LH was not suppressed. The anxiety and stress measures as well as the rating of events rose to high levels just before the jump. With the exception of testosterone, which remained low, serum cortisol, PRL, and GH all increased greatly subsequent to the rise in psychological measures, reached peak values before or shortly after landing, and declined significantly within the next hour. Anxiety and subjective stress scores declined to those of the self-control values within 15 min after landing, but the rating of events scale remained significantly elevated. In summary, reported anxiety associated with a purely psychological stressor was suppressed until within a few hours preceding the event, but was preceded by an increase in sympathetic nervous system activity and suppression of plasma cortisol and salivary testosterone levels. The event itself was associated with a reversal of the cortisol decline; other stress-associated hormones increased, but salivary testosterone remained low.
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Abstract
We have developed a simple, direct radioimmunoassay for progesterone in saliva. The correlation coefficient (r) between the direct assay and an extraction procedure was 0.92 (n = 65, P < 0.001), and the correlation between concurrent serum and salivary progesterone concentrations in the luteal phases of menstrual cycles of 48 women was 0.75 (P < 0.001). Whereas certain polystyrene and polyethylene vials and tubes were found to bind and remove up to 87% of the progesterone from saliva, other plastic and glass surfaces were satisfactory for the procedure. Intraassay and interassay CVs from values greater than 300 pmol/L were 12.0 and 12.4%, respectively. The assay sensitivity was 48 pmol/L. Collection of saliva is a more convenient and less invasive technique for frequent sample collection than phlebotomy, and is useful for monitoring ovulation and assessment of luteal function in women clinically.
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[Involvement of nucleus amygdaloideus centralis, lateral hypothalamus/perifornical region and nucleus paraventricularis in insular cortex-pressor response]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 1997; 49:221-6. [PMID: 9812861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
In urethane-anesthetized, tubocurarine-immobilized and artificially ventilated rats, glutamate (Glu) injection into the insular cortex (INS) and substance P injection into the lateral hypothalamus-perifornical region (LH/PF) or nucleus paraventricularis (NPV) caused pressor responses. Preinjection of procaine or glutamate diethyl ester (GDEE, a glutamate antagonist) bilaterally into the nucleus amygdaloideus centralis (AC) and [D-Pro2, D-Phe7, D-Trp9]-substance P (DPDPDT, a substance P antagonist), but not GDEE, into the LH/PF markedly attenuated the pressor response induced by glutamate injection into the INS. Procaine or DPDPDT preinjection into the NPV also reduced the INS-pressor response. Since the LH/PF and NPV were found to mediate the AC-pressor response, the above results suggest that the INS-pressor response is the final outcome of activation of AC (Glu-receptor)-LH/PF and NPV (SP receptor) system.
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Glucocorticoid remediable aldosteronism: a case report. CHANGGENG YI XUE ZA ZHI 1997; 20:52-7. [PMID: 9178594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Glucocorticoid remediable aldosteronism (GRA) is a hereditary cause of mineralocorticoid hypertension. The most common presentation is asymptomatic hypertension. Hypokalemia, hyperaldosteronism and suppressed plasma renin activity are other forms of primary hyperaldosteronism. However, the aldosterone secretion in these patients is regulated by adrenocortico-tropic hormone (ACTH) rather than the reninangiotension system. Here, we report a patient with a 12-year history of hypertension without response to any treatment until dexamethasone was administered. The diagnosis of GRA was confirmed by elevated plasma level of 18-oxocortisol, which is a unique steroid biochemical abnormality of this disease. In GRA, hybrid steroids (18-oxocortisol and 18-hydroxycortisol) are synthesized at the C-18 carbon of cortisol in a similar way as when corticosterone is converted to aldosterone. The gene duplication defect is on chromosome 8 codes for a chimerical 11 beta-hydroxylase/aldosterone synthase enzyme, causing ectopic expression of aldosterone synthase in zona fasiculata. Because this hypertension is remediable by exogenous glucocorticoid, this case was reported to raise attention about treatable aldosteronism.
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Inhibition of nitric oxide synthase potentiates hypertension and increases mortality in traumatically brain-injured rats. MOLECULAR AND CHEMICAL NEUROPATHOLOGY 1997; 30:125-37. [PMID: 9138424 DOI: 10.1007/bf02815154] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We examined the effects of N omega-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide synthase (NOS), on mortality, morbidity, and cardiovascular parameters following traumatic brain injury (TBI) in the rat. Rats were anesthetized with 2% isoflurane prior to moderate (2.0 atmosphere), central fluid percussion TBI. Temporalis muscle temperature was maintained at 37 +/- 0.5 degrees C. L-NAME (10 mg/kg iv) was administered once at either 5 min before, 5 min after, or 15 min after TBI. Sensorimotor deficits and spatial learning/ memory deficits were assessed after injury. Separate groups of rats were monitored for cardiovascular parameters. Preinjury administration of L-NAME significantly increased mortality from 13 (vehicle) to 70% (associated with pulmonary edema), whereas postinjury, L-NAME had no effect on mortality (14 and 25%). L-NAME administered at 5 or 15 min after injury had no significant effect on motor performance or cognitive performance deficits associated with TBI. L-NAME in uninjured rats increased arterial blood pressure by 25 mmHg within 2 min. L-NAME injected 5 min before TBI greatly prolonged the hypertensive episode associated with TBI (1 min in vehicle vs 60 min in L-NAME). L-NAME injected 5 min after TBI caused a sustained 35 mmHg increase in blood pressure. These findings suggest that acute inhibition of NOS has detrimental consequences on mortality that may be owing to its cardiovascular effects.
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Salivary alpha-amylase as a measure of endogenous adrenergic activity. CLINICAL PHYSIOLOGY (OXFORD, ENGLAND) 1996; 16:433-48. [PMID: 8842578 DOI: 10.1111/j.1475-097x.1996.tb00731.x] [Citation(s) in RCA: 403] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This investigation was designed to evaluate the production rates and concentrations of salivary alpha-amylase as a measure of adrenergic activity under several conditions of stress in human subjects. Saliva and blood samples were simultaneously collected from men at four 15 min intervals both before and after regimens for exercise, a written examination, or a rest period. The regressions of salivary alpha-amylase on plasma norepinephrine (NE) concentrations were significant for both exercise (P < 0.001) and examination (P < 0.01) protocols. Aerobic exercise induced a 3-fold mean increase in alpha-amylase; both NE and epinephrine (EP) increased approximately 5-fold over control levels. Levels of alpha-amylase and NE returned to control levels within 30-45 min after exercise, but EP remained elevated by approximately 2-fold during the remaining hour of observation. During the written examination, alpha-amylase and NE, but not EP, concentrations increased in parallel. In further studies the effects of exercise and exposure to heat and cold on the relationship of salivary alpha-amylase to heart rate and body temperature were investigated. Greater intensities of exercise were associated with greater increases in alpha-amylase concentrations. During heat exposure in a sauna (66 degrees C for 40 min) amylase, heart rate and body temperature all increased progressively. However, during exposure to cold (4 degrees C for 40 min) amylase increased rapidly, though heart rate and body temperature remained unchanged. Salivary cortisol concentrations were unchanged during exposure to heat or cold. We conclude that salivary alpha-amylase concentrations are predictive of plasma catecholamine levels, particularly NE, under a variety of stressful conditions, and may be a more direct and simple end point of catecholamine activity than are changes in heart rate.
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