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1.
J Med Virol ; 96(3): e29556, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38511554

RESUMO

Neutrophil extracellular traps (NETs) play a role in innate pathogen defense and also trigger B-cell response by providing antigens. NETs have been linked to vaccine-induced thrombotic thrombocytopenia. We postulated a potential link between NET biomarkers, NET-promoting autoantibodies, and adverse events (AEs) after COVID-19 vaccine boosters. Healthy donors (HDs) who received ChAdOx1-S (A), mRNA-1273 (M), or recombinant protein (MVC-COV1901) vaccines at the National Taiwan University Hospital between 2021 and 2022 were recruited. We measured serial NET-associated biomarkers, citrullinated-histone3 (citH3), and myeloperoxidase (MPO)-DNA. Serum citH3 and MPO-DNA were significantly or numerically higher in HDs who reported AEs (n = 100, booster Day 0/Day 30, p = 0.01/p = 0.03 and p = 0.30/p = 0.35, respectively). We also observed a positive correlation between rash occurrence in online diaries and elevated citH3. A linear mixed model also revealed significantly higher citH3 levels in mRNA-1273/ChAdOx1-S recipients than MVC-COV1901 recipients. Significant positive correlations were observed between the ratios of anti-heparin platelet factor 4 and citH3 levels on Booster Day 0 and naïve and between the ratios of anti-NET IgM and citH3 on Booster Day 30/Day 0 in the AA-M and MM-M group, respectively. The increased levels of citH3/MPO-DNA accompanied by NET-promoting autoantibodies suggest a potential connection between mRNA-1273/ChAdOx1-S vaccines and cardiovascular complications. These findings provide insights for risk assessments of future vaccines.


Assuntos
COVID-19 , Armadilhas Extracelulares , Humanos , Armadilhas Extracelulares/metabolismo , Vacinas contra COVID-19/efeitos adversos , Autoanticorpos , Vacina de mRNA-1273 contra 2019-nCoV , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , COVID-19/prevenção & controle , COVID-19/metabolismo , Biomarcadores , ChAdOx1 nCoV-19 , Vacinação , DNA/metabolismo , Adenoviridae
2.
Front Endocrinol (Lausanne) ; 14: 1063837, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36817581

RESUMO

Background: Secondary hyperparathyroidism (SHPT) is a common condition in patients with end-stage renal disease (ESRD) who are on dialysis. Parathyroidectomy is a treatment for patients when medical therapy has failed. Recurrence may occur and is indicated for further surgery in the era of improved quality of care for ESRD patients. Methods: We identified, 1060 patients undergoing parathyroidectomy from January, 2011 to June, 2020. After excluding patients without regular check-up at our institute, primary hyperparathyroidism, or malignancy, 504 patients were enrolled. Sixty-two patients (12.3%, 62/504) were then excluded due to persistent SHPT even after the first parathyroidectomy. We aimed to identify risk factors for recurrent SHPT after the first surgery. Results: During the study period, 20% of patients who underwent parathyroidectomy at our institute (in, 2019) was due to recurrence after a previous parathyroidectomy. There were 442 patients eligible for analysis of recurrence after excluding patients with the persistent disease (n = 62). While 44 patients (9.95%) had recurrence, 398 patients did not. Significant risk factors for recurrent SHPT within 5 years after the first parathyroidectomy, including dialysis start time to first operation time < 3 years (p = 0.046), postoperative PTH >106.5 pg/mL (p < 0.001), and postoperative phosphorus> 5.9 mg/dL (p = 0.016), were identified by multivariate analysis. Conclusions: The starting time of dialysis to first operation time < 3 years in the patients with dialysis, postoperative PTH> 106.5 pg/mL, and postoperative phosphorus> 5.9 mg/dL tended to have a higher risk for recurrent SHPT within 5 years after primary treatment.


Assuntos
Hiperparatireoidismo Secundário , Falência Renal Crônica , Humanos , Hormônio Paratireóideo , Recidiva , Hiperparatireoidismo Secundário/complicações , Hiperparatireoidismo Secundário/cirurgia , Paratireoidectomia/efeitos adversos , Fósforo
3.
J Multidiscip Healthc ; 14: 1107-1117, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34017176

RESUMO

The clinical impact of nutrition therapy in critically ill patients has been known for years, and relevant guidelines regarding nutrition therapy have emphasized the importance of proteins. During critical illness, such as sepsis or the state following major surgery, major trauma, or major burn injury, patients suffer from a high degree of stress/inflammation, and during this time, metabolism deviates from homeostasis. The increased degradation of endogenous proteins in response to stress hormones is among the most important events in the acute phase of critical illness. Currently published evidence suggests that adequate protein supplementation might improve the clinical outcomes of critically ill patients. The role of sufficient protein supplementation may even surpass that of caloric supplementation. In this review, we focus on relevant physiological alterations in critical illness, the effects of critical illness on protein metabolism, nutrition therapy in clinical practice, and the function of specific amino acids.

4.
Sci Rep ; 11(1): 7318, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795739

RESUMO

Acinetobacter baumannii-induced nosocomial pneumonia has become a serious clinical problem because of high antibiotic resistance rates. Antimicrobial peptides (AMP) are an ideal alternative strategy due to their broad-spectrum of antimicrobial activity and low incidence of bacterial resistance. However, their application is limited by toxicity and stability in vivo. The present study used a mouse model to directly identify potential AMPs effective for treatment of A. baumannii-induced pneumonia. Fifty-eight AMPs were screened and two identified (SMAP-29 and TP4) to have prophylactic effects which prevented the death of mice with pneumonia. Furthermore, two TP4 derivatives (dN4 and dC4) were found to have therapeutic activity in pneumonia mouse models by peritoneal or intravenous administration. Both dN4 and dC4 also inhibited and/or eliminated A. baumannii biofilms at higher doses. Taken together, these data suggest the AMP derivatives dN4 and dC4 represent a potential treatment strategy for A. baumannii-induced pneumonia.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Pneumonia/tratamento farmacológico , Pneumonia/microbiologia , Infecções por Acinetobacter/microbiologia , Animais , Biofilmes/efeitos dos fármacos , Carbapenêmicos/farmacologia , Química Farmacêutica/métodos , Modelos Animais de Doenças , Desenho de Fármacos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Hemólise , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos , Proteínas Citotóxicas Formadoras de Poros , Células-Tronco
5.
Abdom Radiol (NY) ; 46(6): 2891-2899, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33388808

RESUMO

PURPOSE: Percutaneous cholecystostomy (PC) is an important modality for acute cholecystitis and has been applied for other clinical scenarios as well. In the present study, we aimed to investigate an alternative use of PC for obstructive jaundice. METHODS: From January 2012 to December 2018, eligible subjects were selected from patients undergoing PC in our institute. The characteristics, spectrum of underlying disease, indication for PC performance, details of the procedure, and treatment effect were all investigated. RESULTS: During the study period, 1364 patients underwent PC. Seventy patients fulfilled the defined inclusion criteria. While 47 patients were diagnosed with malignant biliary obstruction with or without cholangitis, 23 patients were diagnosed with nonmalignant biliary obstruction and acute cholangitis. There were 63 patients (90%) diagnosed with acute cholangitis. Pancreatic cancer (n = 24, 51%) and advanced malignancy (n = 28, 59%) were noted mostly in the group with malignant biliary obstruction. Treatment effects were proven by laboratory data, including the white blood cell count, C-reactive protein level, and hepatic function. CONCLUSION: PC can temporize definitive therapies and serve as an alternative treatment for patients with nonmalignant conditions. For patients with advanced malignancy, PC can serve as a palliative procedure that has a high success rate and low complication rate and effectively relieves biliary obstruction.


Assuntos
Colangite , Colecistite Aguda , Colecistostomia , Colestase , Neoplasias Pancreáticas , Colecistite Aguda/cirurgia , Colestase/diagnóstico por imagem , Colestase/cirurgia , Humanos , Estudos Retrospectivos , Resultado do Tratamento
6.
Nutrients ; 10(7)2018 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-30002347

RESUMO

Probiotic supplements are potential therapeutic agents for age-related disorders due to their antioxidant and anti-inflammatory properties. However, the effect of probiotics on age-related brain dysfunction remains unclear. To investigate the effects of Lactobacillus paracasei PS23 (LPPS23) on the progression of age-related cognitive decline, male and female senescence-accelerated mouse prone 8 (SAMP8) mice were divided into two groups (n = 6 each): the control and PS23 groups. From the age of 16 weeks, these groups were given saline and LPPS23, respectively, because SAMP8 mice start aging rapidly after four months of age. After 12 weeks of treatment, we evaluated the effect of LPPS23 by analyzing their appearance, behavior, neural monoamines, anti-oxidative enzymes, and inflammatory cytokines. The PS23 group showed lower scores of senescence and less serious anxiety-like behaviors and memory impairment compared to the control group. The control mice also showed lower levels of neural monoamines in the striatum, hippocampus, and serum. Moreover, LPPS23 induced the anti-oxidative enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx). Higher levels of tumor necrosis factor (TNF)-α and monocyte chemotactic protein-1 (MCP1) and lower levels of interleukin (IL)-10 indicated that LPPS23 modulated the inflammation. Our results suggest that LPPS23 supplements could delay age-related cognitive decline, possibly by preventing oxidation and inflammation and modulating gut⁻brain axis communication.


Assuntos
Comportamento Animal , Cognição , Envelhecimento Cognitivo/psicologia , Disfunção Cognitiva/microbiologia , Disfunção Cognitiva/psicologia , Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Lacticaseibacillus paracasei/fisiologia , Probióticos/administração & dosagem , Fatores Etários , Animais , Monoaminas Biogênicas/sangue , Biomarcadores/sangue , Disfunção Cognitiva/sangue , Disfunção Cognitiva/fisiopatologia , Citocinas/sangue , Modelos Animais de Doenças , Progressão da Doença , Feminino , Glutationa Peroxidase/sangue , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Mediadores da Inflamação/sangue , Masculino , Camundongos , Estresse Oxidativo , Superóxido Dismutase/sangue , Fatores de Tempo
7.
Int J Surg ; 55: 182-187, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29883619

RESUMO

BACKGROUND: Cranial metastasis of thyroid cancer is rare. The aim of this study was to analyse the clinical characteristics, treatments and outcomes of thyroid cancer patients with cranial metastasis and to identify the associated prognostic factors. MATERIALS AND METHODS: Between January 1977 and August 2017, a total of 4683 patients were histologically confirmed to have thyroid cancer. Among them, 25 patients (0.53%) were identified as having cranial metastases, and their medical records were reviewed. The Kaplan-Meier method with a log-rank test was performed with cancer-specific survival as the main outcome. Cox regression analysis was used to examine the potential prognostic factors influencing patient survival. RESULTS: Of the 25 patients, 21 were female, and 4 were male. The median age at the time of diagnosis of cranial metastasis was 63 years. Sixteen patients had metastases to the brain, and nine patients had metastases involving the skull only. Papillary carcinoma and follicular carcinoma accounted for 84.0% of cases. Twenty-four cases (96.0%) had extracranial metastases at the time of diagnosis of cranial metastases. Twenty patients received surgery, and 4 patients received palliative radiotherapy. One patient received supportive care only. The median cancer-specific survival after the diagnosis of cranial metastases was 27 months. According to the Kaplan-Meier test, 3 factors had a significant impact on survival, the metastatic site, histological types and surgical resection. According to the Cox regression analysis, skull metastases (HR: 0.274, 95% CI: 0.083-0.904, p = 0.033) and surgical resection (HR: 0.134, 95% CI: 0.019-0.929, p = 0.042) were identified as independent prognostic factors for a better outcome. CONCLUSIONS: Surgical resection is the mainstay therapy for thyroid cancer patients with cranial metastasis. Cranial metastases involving the skull only are associated with a better outcome.


Assuntos
Adenocarcinoma Folicular/mortalidade , Neoplasias Encefálicas/mortalidade , Carcinoma Papilar/mortalidade , Neoplasias Cranianas/mortalidade , Neoplasias da Glândula Tireoide/mortalidade , Adenocarcinoma Folicular/secundário , Adenocarcinoma Folicular/cirurgia , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Carcinoma Papilar/secundário , Carcinoma Papilar/cirurgia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Análise de Regressão , Estudos Retrospectivos , Neoplasias Cranianas/secundário , Neoplasias Cranianas/cirurgia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Fatores de Tempo
8.
Medicine (Baltimore) ; 95(28): e4194, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27428220

RESUMO

BACKGROUND: the difference in the risk of thyroid malignancy for patients with multinodular goiter (MNG) and solitary nodular goiter (SNG) remains controversial. Although total thyroidectomy (TT) is the current preferred surgical option for MNG, permanent hypothyroidism in these patients may be a concern. Therefore, we discuss whether nontotal thyroidectomy is a reasonable alternative surgical option. METHODS: A retrospective cohort study was performed for 1598 consecutive patients who underwent thyroid surgery for nodular goiter between January 2007 and December 2012. Numerous clinical parameters were collected and analyzed. RESULTS: We reviewed 795 patients with MNG and 803 patients with SNG. The prevalence of malignancy on final pathology was significantly higher in the patients with MNG than in the patients with SNG (15.6% vs 10.1%, P = 0.001). However, a multivariate analysis revealed that this difference was insignificant (P = 0.50). Papillary carcinoma was the predominant type in both groups, but papillary microcarcinoma was more frequently found (41.1%) in the patients with MNG. The only multifocal cancers were of the papillary carcinoma histologic type, and the incidence of multifocal papillary carcinoma was significantly higher in the patients with MNG (23.4% vs 7.4%, P = 0.005). Reoperation was not required for the patients who underwent TT for goiter recurrence or incidental carcinoma. The overall rate of recurrence following nontotal thyroidectomy was 12.2%. Among the patients who underwent reoperation for goiter recurrence, 2 (20.0%) were complicated with permanent hypoparathyroidism. Among the patients who underwent a nontotal bilateral thyroidectomy, an average of 56.5% had permanent hypothyroidism. CONCLUSIONS: Multinodularity does not increase the risk of thyroid malignancy. However, patients with MNG who develop papillary carcinoma are at an increased risk of cancer multifocality. If a patient can tolerate lifelong thyroid hormone replacement, TT is the preferred surgical option because it helps avoid reoperation and the associated complications. Nontotal bilateral thyroidectomy does not ensure the preservation of thyroid hormone function.


Assuntos
Carcinoma Papilar/patologia , Bócio Nodular/patologia , Bócio Nodular/cirurgia , Neoplasias da Glândula Tireoide/patologia , Feminino , Humanos , Hipoparatireoidismo/etiologia , Hipotireoidismo/etiologia , Masculino , Pessoa de Meia-Idade , Recidiva , Reoperação , Estudos Retrospectivos , Risco , Tireoidectomia , Resultado do Tratamento
9.
Int J Surg ; 27: 46-52, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26796368

RESUMO

BACKGROUND: When to use a thoracic approach to treat substernal goitres has often been discussed in the literature. But there are few published reports describing surgical outcomes and associated complications for patients with right-sided vs. left-sided substernal goitres. OBJECTIVE: This study evaluated the characteristics and clinical outcomes of patients who underwent surgical management of substernal goitres, presenting factors indicating the use of a thoracic approach and differences between right- and left-sided goitre extensions. DESIGN: Retrospective cohort study. SETTING: Tertiary referral centre. METHODS: Between January 2007 and December 2012, 2104 patients underwent thyroidectomy at Chang Gung Memorial Hospital and 140 (6.7%) were diagnosed with substernal goitres. Patient medical records were retrospectively reviewed, and data were analysed to assess surgical outcomes. RESULTS: Seven (5.0%) patients required a thoracic approach for goitre removal. Goitre malignancy was verified in 17 (12.1%) patients. The most common postoperative complication was transient hypoparathyroidism (15.0%). Permanent RLN injury occurred in 4.3% of patients and was significantly more frequent using the thoracic approach. Unilateral extension of a substernal goitre was more common than bilateral extension. Right- and left-sided extensions occurred with equal frequency. The rate of postoperative complications was similar between groups and there were no patient deaths. CONCLUSION: Chest radiography and thyroid sonography may provide initial radiologic evidence of goitre extension into the superior mediastinum. Computed tomography evaluation of the depth of goitre extension to the tracheal bifurcation was the strongest predictor of the need to use a thoracic approach. There were no significant differences in the clinical features and outcomes of patients with right- and left-sided substernal goitres. The right recurrent laryngeal nerve shows increased susceptibility to damage during thyroid surgery for substernal goitres. The incidence of malignant substernal goitres is similar to that of malignant cervical goitres.


Assuntos
Bócio Subesternal/cirurgia , Complicações Pós-Operatórias/epidemiologia , Tireoidectomia/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Bócio Subesternal/patologia , Humanos , Hipoparatireoidismo/epidemiologia , Hipoparatireoidismo/etiologia , Masculino , Mediastino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Radiografia Torácica , Nervo Laríngeo Recorrente , Estudos Retrospectivos , Centros de Atenção Terciária , Glândula Tireoide/diagnóstico por imagem , Tireoidectomia/métodos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
10.
Anticancer Res ; 34(9): 5029-36, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25202087

RESUMO

AIM: Imatinib mesylate (IM) is effective in metastatic gastrointestinal stromal tumor (GIST) patients; however, disease progression eventually occurs due to IM resistance or intolerance. Treatment options include IM escalation or a direct shift to sunitinib, but comparison of these strategies is required. PATIENTS AND METHODS: This study included 91 out of 214 metastatic GIST patients treated with IM, who experienced progression or intolerance between August 2001 and December 2012 at the Chang Gung Memorial Hospital. Treatment efficacy and safety profiles were retrospectively compared between groups of patients who either received escalated IM or were directly switched to sunitinib. RESULTS: There were no significant differences in age, gender, second-line treatment causes or gene mutations in the IM escalation group (N=63) versus the sunitinib group (N=28). The 2 groups had similar progression-free survival (PFS, p=0.316) and overall survival (OS, p=0.599). Patients without primary KIT exon 9 mutations and who treated with sunitinib had significantly better PFS (14.3 vs. 6.2 months, p=0.037) and a trend toward better OS (not reached vs. 16.4 months, p=0.161) compared to the IM-escalation group. Patients in both groups with responses and stable disease (SD), and IM escalation patients who underwent surgery and who had KIT exon 9 mutations, had favorable PFS. The most common non-hematological adverse events were edema in the IM escalation group and hand-foot syndrome and hypertension in the sunitinib group. CONCLUSION: Comparable results were achieved by IM escalation and sunitinib treatment. Physicians should consider kinase mutations and specific adverse effects when choosing between these treatments.


Assuntos
Benzamidas/uso terapêutico , Neoplasias Gastrointestinais/tratamento farmacológico , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/patologia , Indóis/uso terapêutico , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Benzamidas/administração & dosagem , Benzamidas/efeitos adversos , Substituição de Medicamentos , Feminino , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/mortalidade , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/mortalidade , Humanos , Mesilato de Imatinib , Indóis/administração & dosagem , Indóis/efeitos adversos , Masculino , Pessoa de Meia-Idade , Mutação , Metástase Neoplásica , Piperazinas/administração & dosagem , Piperazinas/efeitos adversos , Prognóstico , Proteínas Proto-Oncogênicas c-kit/genética , Pirimidinas/administração & dosagem , Pirimidinas/efeitos adversos , Pirróis/administração & dosagem , Pirróis/efeitos adversos , Retratamento , Sunitinibe , Resultado do Tratamento , Adulto Jovem
11.
PLoS One ; 9(5): e96292, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24852749

RESUMO

BACKGROUND: Colibactin is a nonribosomal peptide-polyketide synthesized by multi-enzyme complexes encoded by the pks gene cluster. Colibactin-producing Escherichia coli have been demonstrated to induce host DNA damage and promote colorectal cancer (CRC) development. In Taiwan, the occurrence of pyogenic liver abscess (PLA) has been suggested to correlate with an increasing risk of CRC, and Klebsiella pneumoniae is the predominant PLA pathogen in Taiwan. METHODOLOGY/PRINCIPAL FINDINGS: At the asn tRNA loci of the newly sequenced K. pneumoniae 1084 genome, we identified a 208-kb genomic island, KPHPI208, of which a module identical to the E. coli pks colibactin gene cluster was recognized. KPHPI208 consists of eight modules, including the colibactin module and the modules predicted to be involved in integration, conjugation, yersiniabactin production, microcin production, and unknown functions. Transient infection of BALB/c normal liver cells with K. pneumoniae 1084 increased the phosphorylation of histone H2AX, indicating the induction of host DNA damage. Colibactin was required for the genotoxicity of K. pneumoniae 1084, as it was diminished by deletion of clbA gene and restored to the wild type level by trans-complementation with a clbA coding plasmid. Besides, BALB/c mice infected with K. pneumoniae 1084 exhibited enhanced DNA damage in the liver parenchymal cells when compared to the isogenic clbA deletion mutant. By PCR detection, the prevalence of pks-positive K. pneumoniae in Taiwan is 25.6%, which is higher than that reported in Europe (3.5%), and is significantly correlated with K1 type, which predominantly accounted for PLA in Taiwan. CONCLUSIONS: Our knowledge regarding how bacteria contribute to carcinogenesis has just begun. The identification of genotoxic K. pneumoniae and its genetic components will facilitate future studies to elucidate the molecular basis underlying the link between K. pneumoniae, PLA, and CRC.


Assuntos
Infecções por Klebsiella/complicações , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , Família Multigênica , Mutagênicos/metabolismo , Peptídeos/genética , Animais , Linhagem Celular , Dano ao DNA , Deleção de Genes , Genes Bacterianos , Humanos , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/genética , Klebsiella pneumoniae/fisiologia , Fígado/microbiologia , Abscesso Hepático Piogênico/etiologia , Abscesso Hepático Piogênico/genética , Abscesso Hepático Piogênico/microbiologia , Camundongos Endogâmicos BALB C , Policetídeos , Taiwan/epidemiologia
12.
Int J Pharm ; 441(1-2): 381-8, 2013 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-23220078

RESUMO

The aim of this work is to establish an optimal process for generating liposomal berberine and assessing its anticancer ability against human hepatic carcinoma in a murine xenograft model. Of various forms of liposomal berberine with different lipid compositions, preparation by various methods, the one that contained 5 mol% polyethenyl glycol (PEG) that was produced by a thin-film hydration/extrusion method exhibited the highest encapsulation efficiency (E.E.) of berberine (14%). Additionally, in vitro studies reveal that this batch of liposomal berberine inhibited the growth of HepG2 cells 2.5 times as effectively as berberine solution since the half maximal inhibitory concentration (IC(50)) of berberine solution was 4.23 µg berberine/mL while that of liposomal berberine was only 1.67 µg berberine/mL, and this inhibition effect was based on the induction of apoptosis through the caspase/mitochondria-dependent pathway. Additionally, the results of in vivo studies indicate that the liposome effectively reduced the rate of elimination of berberine in both plasma and tissues, and liposomal berberine effectively reduced the size and weight of tumors as compared with the untreated tumor control group. Therefore, this work demonstrates that liposome is a good carrier for berberine to inhibit the tumor growth in HepG2 tumor-bearing mice.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Berberina/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Apoptose/efeitos dos fármacos , Berberina/administração & dosagem , Carcinoma Hepatocelular/patologia , Caspases/metabolismo , Excipientes/química , Células Hep G2 , Humanos , Concentração Inibidora 50 , Lipossomos , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Nus , Mitocôndrias/metabolismo , Polietilenoglicóis/química , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Biochem Biophys Res Commun ; 291(1): 165-9, 2002 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11829478

RESUMO

The potential residue at the autoprocessing site for improving processing efficiency was evaluated from hydrolysis of 19 cleavage-site-mimicking octapeptides, VTTXQTVP (-4 to +4), by the mature subtilisin YaB and YaB-G124A mutants. Both enzymes cleaved the octapeptides mainly at two sites, X-Q (A-site) and Q-T (B-site), at varied preferences. Based on the results above, Met(-1) of YaB-G124A was mutated and, as expected, extracellular enzyme production increased with Gln or Ala replacement, but decreased with Ile or Asp substitution. Together with previous structural studies, our results suggest that autoprocessing is dependent on not only the primary structure, but also the peptide flexibility around the processing site. Cleavage at the B-site resulted in a novel YaB mutant lacking the N-terminus Gln 1, which led the mutant enzyme to less enzymatic activity by 80% and less thermal stability by 20 degrees C, perhaps due to its ligation to the high-affinity calcium ion.


Assuntos
Mutagênese Sítio-Dirigida , Processamento de Proteína Pós-Traducional/fisiologia , Subtilisina/química , Subtilisina/metabolismo , Substituição de Aminoácidos , Bacillus subtilis , Sítios de Ligação , Cromatografia Líquida de Alta Pressão , Ativação Enzimática/fisiologia , Estabilidade Enzimática , Hidrólise , Peptídeos/química , Relação Estrutura-Atividade , Especificidade por Substrato , Subtilisina/genética
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