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1.
Opt Express ; 32(3): 2906-2915, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297527

RESUMO

We present a novel micro-fabrication technique for creating concave surfaces on the endfacets of photonic crystal fibers. A fiber fusion splicer is used to generate arc discharges to melt and reshape the fiber endfacet. This technique can produce large spherical concave surfaces with roughness as low as 0.12 nm in various types of photonic crystal fibers. The deviation of fabricated surface and a spherical profile in the region of 70 µm in diameter is less than 50 nm. The center of the concave surface and the fiber mode field are highly coincident with a deviation less than 500 nm. Finesse measurements have shown that a Fabry-Pérot cavity composed of the fiber fabricated using this method and a plane mirror maintains finesse of 20000. This method is easy to replicate, making it a practical and efficient approach to fabricate concave surface on fibers for open-access fiber Fabry-Pérot cavities.

2.
BMC Gastroenterol ; 24(1): 176, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773485

RESUMO

BACKGROUND: Angiogenesis is a critical step in colorectal cancer growth, progression and metastasization. CT are routine imaging examinations for preoperative clinical evaluation in colorectal cancer patients. This study aimed to investigate the predictive value of preoperative CT enhancement rate (CER) and CT perfusion parameters on angiogenesis in colorectal cancer, as well as the association of preoperative CER and CT perfusion parameters with serum markers. METHODS: This retrospective analysis included 42 patients with colorectal adenocarcinoma. Median of microvessel density (MVD) as the cut-off value, it divided 42 patients into high-density group (MVD ≥ 35/field, n = 24) and low-density group (MVD < 35/field, n = 18), and 25 patients with benign colorectal lesions were collected as the control group. Statistical analysis of CER, CT perfusion parameters, serum markers were performed in all groups. Receiver operating curves (ROC) were plotted to evaluate the diagnostic efficacy of relevant CT perfusion parameters for tumor angiogenesis; Pearson correlation analysis explored potential association between CER, CT perfusion parameters and serum markers. RESULTS: CER, blood volume (BV), blood flow (BF), permeability surface (PS) and carbohydrate antigen 19 - 9 (CA19-9), carbohydrate antigen 125 (CA125), carcinoembryonic antigen (CEA), trefoil factor 3 (TFF3), vascular endothelial growth factor (VEGF) in colorectal adenocarcinoma were significantly higher than those in the control group, the parameters in high-density group were significantly higher than those in the low-density group (P < 0.05); however, the time to peak (TTP) of patients in colorectal adenocarcinoma were significantly lower than those in the control group, and the high-density group showed a significantly lower level compared to the low-density group (P < 0.05). The combined parameters BF + TTP + PS and BV + BF + TTP + PS demonstrated the highest area under the curve (AUC), both at 0.991. Pearson correlation analysis showed that the serum levels of CA19-9, CA125, CEA, TFF3, and VEGF in patients showed positive correlations with CER, BV, BF, and PS (P < 0.05), while these indicators exhibited negative correlations with TTP (P < 0.05). CONCLUSIONS: Some single and joint preoperative CT perfusion parameters can accurately predict tumor angiogenesis in colorectal adenocarcinoma. Preoperative CER and CT perfusion parameters have certain association with serum markers.


Assuntos
Adenocarcinoma , Antígeno Carcinoembrionário , Neoplasias Colorretais , Neovascularização Patológica , Valor Preditivo dos Testes , Tomografia Computadorizada por Raios X , Humanos , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Neoplasias Colorretais/irrigação sanguínea , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/sangue , Adenocarcinoma/patologia , Adenocarcinoma/irrigação sanguínea , Idoso , Neovascularização Patológica/diagnóstico por imagem , Neovascularização Patológica/sangue , Tomografia Computadorizada por Raios X/métodos , Antígeno Carcinoembrionário/sangue , Biomarcadores Tumorais/sangue , Adulto , Densidade Microvascular , Antígeno CA-19-9/sangue , Curva ROC , Fator A de Crescimento do Endotélio Vascular/sangue , Volume Sanguíneo , Cuidados Pré-Operatórios/métodos
3.
Int J Colorectal Dis ; 37(9): 2021-2029, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35997991

RESUMO

OBJECTIVES: To evaluate the value of preoperative CT energy spectrum imaging in detecting lymph node metastasis of colorectal cancer. METHODS: From September 2019 to November 2021, a retrospective study was performed for the eighty-two patients with colorectal cancer through preoperative colonoscopy or surgical pathology confirmed in our hospital. Based on the lymph node metastasis status, these cases were divided into the metastasis and non-metastasis groups. GE Revolution CT scanner was used to scan the patients with energy spectrum imaging, it measured and recorded the single-energy CT values from 40 to 140 keV and various energy spectrum parameters of lymph nodes around the lesions in the arterial and venous phases, and statistically analyze the above indices. RESULTS: In the arterial and venous phases: the single-energy CT values of 40-140 keV in the non-metastatic group were higher than those in the metastatic group (all P < 0.05); the parameter values of IC (iodine concentration), NIC (normalized iodine concentration), λ (the slope of the energy spectrum curve), and Eff-Z (effective-Z) in the non-metastatic group were higher than those in the metastatic group (all P < 0.05). Further evaluation of ROC curve showed that the higher AUC (area under curve) of the single-energy CT value of 50 keV in the arterial phase was 0.889, among the energy spectrum parameters of IC, NIC, λ, and Eff-Z, the NIC had the better diagnostic efficiency and the AUC of the NIC was 0.873, the highest AUC of the combination of NIC and λ was 0.885 when the energy spectrum parameters were combined. The higher AUC of the single-energy CT value of 60 keV in the venous phase was 0.853, among the energy spectrum parameters of IC, NIC, λ, and Eff-Z, the λ had the better diagnostic efficiency and the AUC of the λ was 0.822, the higher AUC of the combination of NIC, λ, and Eff-Z was 0.840 when the energy spectra were combined. CONCLUSIONS: Parameters of energy spectrum CT imaging can effectively evaluate whether lymph nodes have metastases, and provide favorable imaging diagnosis basis for the range and the number of lymph nodes to be cleaned during clinical operation and can evaluate the prognosis of patients. It is worthy of clinical recommendation.


Assuntos
Neoplasias Colorretais , Iodo , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/patologia , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Estudos Retrospectivos , Tomografia Computadorizada Espiral , Tomografia Computadorizada por Raios X/métodos
4.
Lipids Health Dis ; 14: 157, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26630989

RESUMO

BACKGROUND: Exercise is beneficial for blood glucose metabolism. However, whether moderate aerobic exercise could improve impaired fasting glucose is unknown. And the mechanism is also needed to investigate. METHODS: A cross-sectional research was performed and 120 participants with impaired fasting glucose (IFG) were randomly assigned into active and controlled groups. Briefly, participants in active group were required to take moderate aerobic exercise at least 30 min for five times per week, whereas in controlled group, participants were also advised to take exercise but not mandatorily required the same degree as that of active group. At baseline and 3 month's follow-up, laboratory and demographic variables were compared. RESULTS: At baseline, no significant between-group differences were observed. Generally, leukocyte ROCK2 activity in the active and controlled groups were 58.7 ± 6.0 mg/mL and 60.2 ± 7.3 mg/mL, and daily average exercise time at baseline in both groups was extremely little, with 5.2 ± 3.8 min and 5.9 ± 3.5 min, respectively. After 3 months' follow-up, 52 and 56 participants in the active and controlled groups completed the whole program. Compared to baseline, leukocyte ROCK2 activity and daily average exercise time were improved in both groups. Nonetheless, compared to the controlled group, leukocyte ROCK2 activity was reduced more profoundly and the daily average exercise time was longer in the active group (37.5 ± 6.3 min versus 18.3 ± 7.2 min, p < 0.05). Moreover, the percentage of IFG in the active group was decreased more prominently than the controlled group (76.9% versus 82.1%, p < 0.05). Multivariate regression analyses revealed that exercise time and leukocyte ROCK2 activity was significantly associated with IFG, with OR of 0.836 (active group versus controlled group, 95% CI 0.825-0.852, p < 0.05) in exercise time, and 1.043 (controlled group versus active group, 95% CI 1.021-1.069, p < 0.05) in leukocyte ROCK2 activity. In addition, exercise time was significantly associated with leukocyte ROCK2 activity, with OR of 0.822 (active group versus controlled group, 95% CI 0.818-0.843, p < 0.05). CONCLUSION: In subjects with IFG, increased daily average exercise time is beneficial for improving fasting blood glucose metabolism, and the mechanism may be associated with its effects on attenuating leukocyte ROCK2 activity.


Assuntos
Hiperglicemia/terapia , Adulto , Glicemia , Estudos Transversais , Exercício Físico , Terapia por Exercício , Feminino , Humanos , Hiperglicemia/sangue , Leucócitos/enzimologia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Quinases Associadas a rho/metabolismo
5.
World J Clin Cases ; 10(35): 13115-13121, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36569015

RESUMO

BACKGROUND: We describe a case of relentless placoid chorioretinitis (RPC) that progressed despite administration of peribulbar and systemic corticosteroids, and was resolved by systemic combined with intravitreal methotrexate. CASE SUMMARY: A 16-year-old male reported painless blurred vision and a temporal scotoma in his right eye for one week. Due to widespread distribution and continuous enlargement, multimodal imaging of the lesions led to the diagnosis of RPC. Lesions in the right eye extended despite peribulbar injection of triamcinolone acetonide, but the progression was immediately terminated by a single dose of intravitreal methotrexate. A new fresh lesion occurred in the contralateral eye despite systemic prednisolone but was resolved by oral methotrexate. CONCLUSION: Systemic immunosuppressants should be given upon RPC diagnosis. Intravitreal methotrexate immediately halted progression and may be considered for sight-threatening cases as part of the initial therapy.

6.
Artigo em Inglês | MEDLINE | ID: mdl-35656468

RESUMO

Objective: To investigate the correlation of CT perfusion-related parameters with serum vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (BFGF) in patients with primary liver cancer. Methods: A total of 100 patients with primary liver cancer who were treated in our hospital from June 2019 to June 2021 were selected as the observation group, and 90 patients with benign liver lesions during the same period were selected as the control group. The CT perfusion-related parameters (perfusion volume and perfusion index) and serum VEGF and BFGF levels were compared between the two groups. Pearson correlation was used to analyze the correlation between CT perfusion-related parameters and serum VEGF and BFGF levels. Results: Compared to the control group, significantly higher HAP and lower HPP and TLP were observed in the observation group. The perfusion volume indexes of patients with different stages of liver cancer in the observation group were statistically different (P < 0.05). Compared to the control group, the observation group witnessed significantly higher HAPI and lower HPPI. There were statistically significant differences in the perfusion index of patients with different stages of primary liver cancer in the observation group (P < 0.05). The serum VEGF and BFGF levels in the observation group were significantly higher than those in the control group, and the serum VEGF and BFGF levels in patients with different stages of primary liver cancer in the observation group were statistically different (P < 0.05). Pearson correlation analysis showed that HAP and HAPI were positively correlated with VEGF and BFGF (r = 0.986, P ≤ 0.001; r = 0.983, P ≤ 0.001), and HPP, TLP, and HPPI were negatively correlated with VEGF and BFGF (r = -0.992, P ≤ 0.001; r = -0.993, P ≤ 0.001; r = -0.995, P ≤ 0.001). Conclusion: CT perfusion-related parameters and serum VEGF and BFGF levels in patients with primary liver cancer are abnormally expressed, and there is a strong correlation between the two, which might aid clinical diagnosis and treatment.

7.
Front Med (Lausanne) ; 8: 750760, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35004721

RESUMO

Purpose: To evaluate the safety and efficacy of continuous high-dose (6 mg) intravitreal ganciclovir injections (IVG) for cytomegalovirus (CMV) retinitis (CMVR) after haploidentical hematopoietic stem cell transplantation (Haplo-HSCT), and to explore factors that may influence the treatment procedure. Design: Prospective, randomized, single-blinded, positive-controlled, interventional, comparative study. Methods: A total of 22 patients with CMVR (32 eyes) were randomized to either high-dose group (IVG 6 mg weekly) or low-dose group (IVG 3 mg given twice weekly for 2 weeks as induction phase and weekly thereafter as maintenance phase). Patients who were recorded any positive CMV DNAemia or other active CMV diseases and needed systemic anti-CMV treatment during the study period were excluded. The vision outcome, variables of the treatment procedure, and incidence of complication and CMVR recurrence were analyzed and compared. Logistic regression was applied to determine the factors that may have an impact on the treatment process at baseline. Results: Compared to the low-dose group, the high-dose group resulted in a median of two less intravitreal injections (4 vs. 6 times, respectively, P = 0.016), while the rate of vision stability or improvement (81.2 vs. 87.5%), the incidence of complication (6.2 vs. 18.8%), and CMVR recurrence (12.5% vs. 6.2%) were similar (all P > 0.05). No drug-related toxicity was observed. Initial aqueous CMV-DNA load (OR: 6.872, 95% CI: 1.335-35.377, P = 0.021) and extension of lesion (OR: 0.942, 95% CI: 0.897 to .991, P = 0.020), but not dosing regimen (P = 0.162), were predictors of the treatment duration. Conclusions: Continuous high-dose regimen was well tolerated and resulted in less intravitreal injections, with similar vision outcomes and safety profiles. The clinical course of CMVR after Haplo-HSCT was determined by its own nature at baseline and could not be modified by treatment protocols under consistent immune background.

8.
World J Stem Cells ; 12(1): 87-99, 2020 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-32110277

RESUMO

BACKGROUND: Breast cancer is a common malignant tumor that seriously threatens women's health. Breast cancer stem cell (CSC)-like cell population may be the main factor for breast cancer metastasis. Therefore, targeted therapy for CSCs has great potential significance. Hypoxia-inducible factor is a transcription factor widely expressed in tumors. Studies have shown that down-regulation of the hypoxia signaling pathway inhibits tumor stem cell self-renewal and increases the sensitivity of stem cells to radiotherapy and chemotherapy mediated by hypoxia-inducible factor-2α (HIF-2α). However, the specific mechanism remains unclear and further research is necessary. AIM: To investigate the effect of HIF-2α down-regulation on stem cell markers, microsphere formation, and apoptosis in breast cancer cell line MDA-MB-231 under hypoxia and its possible mechanism. METHODS: Immunohistochemistry was used to detect the expression of HIF-2α and CD44 in triple-negative breast cancer (TNBC) and non-TNBC tissues. Double-labeling immunofluorescence was applied to detect the co-expression of HIF-2α and CD44 in MDA-MB-231 cells and MCF-7 cells. HIF-2α was silenced by RNA interference, and the expression of CD44 and transfection efficiency were detected by real-time fluorescent quantitative PCR. Further, flow cytometry, TdT-mediated X-dUTP nick end labeling, and mammosphere formation assays were used to evaluate the effect of HIF-2α on CSCs and apoptosis. The possible mechanisms were analyzed by Western blot. RESULTS: The results of immunohistochemistry showed that HIF-2α was highly expressed in both TNBC and non-TNBC, while the expression of CD44 in different molecular types of breast cancer cells was different. In in vitro experiments, it was found that HIF-2α and CD44 were expressed almost in the same cell. Compared with hypoxia + negative-sequence control, HIF-2α small interfering ribonucleic acid transfection can lower the expression of HIF-2α and CD44 mRNA(P < 0.05), increase the percentage of apoptotic cells (P < 0.05), and resulted in a reduction of CD44+/CD24- population (P < 0.05) and mammosphere formation (P < 0.05) in hypoxic MDA-MB-231 cells. Western blot analysis revealed that phosphorylated protein-serine-threonine kinase (p-AKT) and phosphorylated mammalian target of rapamycin (p-mTOR) levels in MDA-MB-231 decreased significantly after HIF-2α silencing (P < 0.05). CONCLUSION: Down-regulation of HIF-2α expression can inhibit the stemness of human breast cancer MDA-MB-231 cells and promote apoptosis, and its mechanism may be related to the CD44/phosphoinosmde-3-kinase/AKT/mTOR signaling pathway.

9.
World J Gastrointest Oncol ; 11(12): 1206-1217, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31908725

RESUMO

BACKGROUND: Accurate assessment of the prognosis after colorectal cancer surgery is of great significance in patients with colorectal cancer. However, there is no systematic analysis of factors affecting the prognosis of colorectal cancer currently. AIM: To systematically analyze the influence of clinical data and serological and histological indicators on the prognosis of patients with colorectal cancer, and to explore the indicators that can accurately assess the prognosis of patients with colorectal cancer. METHODS: A total of 374 patients with colorectal cancer were enrolled. The clinical data, tumor-node-metastasis (TNM) stage, and Dukes stage were recorded. All patients received examinations including carcinoembryonic antigen (CEA), carbohydrate antigen 199, C-reactive protein, albumin, D-dimer, and fibrinogen as well as routine blood tests one week before surgery. The tumor location, size, depth of invasion, lymph node metastasis, and distant metastasis were recorded during surgery. The pathological tissue typing and expression of proliferating cell nuclear antigen (PCNA) and p53 were observed. All patients were followed for 3 years, and patients with endpoint events were defined as a poor prognosis group, and the remaining patients were defined as a good prognosis group. The differences in clinical data, serology, and histology were analyzed between the two groups. Multivariate COX regression was used to analyze the independent influencing factors for the prognosis of colorectal cancer. The receiver operating characteristic curve was used to evaluate the predictive value of each of the independent influencing factors and their combination for the prognosis of colorectal cancer. RESULTS: The follow-up outcomes showed that 81 patients were in the good prognosis group and 274 patients in the poor prognosis group. The TNM stage, PCNA, Glasgow prognostic score (GPS), neutrophil-lymphocyte ratio (NLR), C-reactive protein/albumin ratio (CAR), D-dimer, and CEA were independent influencing factors for the prognosis of colorectal cancer (P = 0.000). NLR had the highest predictive power for colorectal cancer prognosis [area under the receiver operating characteristic curve (AUC) = 0.925], followed by D-dimer (AUC = 0.879) and GPS (AUC = 0.872). The accuracy of the combination of all indicators in predicting the prognosis of colorectal cancer was the highest (AUC = 0.973), which was significantly higher than that of any of the indicators alone (P < 0.05). The sensitivity and specificity of the combination were 92.59% and 90.51%, respectively. CONCLUSION: The independent influence factors for the prognosis of colorectal cancer include TNM stage, PCNA, GPS, NLR, CAR, D-dimer, and CEA. The combined assessment of the independent factors is the most accurate predictor of the prognosis after colorectal cancer surgery.

10.
Nan Fang Yi Ke Da Xue Xue Bao ; 36(11): 1573-1576, 2016 Nov 20.
Artigo em Zh | MEDLINE | ID: mdl-27881353

RESUMO

OBJECTIVE: To explore the correlation of homocysteine with diabetic microangiopathy and the change after drug intervention. METHODS: A total of 200 patients with type 2 diabetes were selected between January and December 2013. The patients were divide into group of no microvascular disease and group of microvascular lesion according to the complications. Blood lipid, blood glucose, renal function and serum homocysteine were deteced pre-treatment and after 6 months treatment.A total of 100 cases of healthy subjects with physical examination over the same period were selected as control group according to the principle of age and gender matching. RESULTS: SBP, DBP, TG, TC, LDL, FBG, 2 hPBG, HbA1, SUN, SCr and HCY in group of no microvascular disease and group of microvascular lesion were significantly higher than that in control group(P<0.01), while HDL were significantly lower(P<0.01); SBPDBP,SUN,SCr and HCY in group of microvascular lesion were significantly higher than that in group of no microvascular disease(P<0.01); Multi factor Logistic regression analysis showed blood pressure, urea nitrogen, serum creatinine and homocysteine levels are risk factors for microvascular complications in patients with diabetes mellitus; HCY after treatment were significantly lower than that before treatment in group of no microvascular disease and group of microvascular lesion than(P<0.01). CONCLUSION: High homocysteine levels are risk factor of diabetic microvascular disease, and the homocysteine levels can be reduced after treatment.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/sangue , Homocisteína/sangue , Glicemia , Pressão Sanguínea , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Lipídeos/sangue , Fatores de Risco
11.
Artigo em Inglês | MEDLINE | ID: mdl-26114653

RESUMO

Herein, we report an on-line two-dimensional system constructed by counter-current chromatography (CCC) coupling with preparative high-performance liquid chromatography (prep-HPLC) for the separation and purification of polar natural products. The CCC was used as the first dimensional isolation column, where an environmental friendly polar two-phase solvent system of isopropanol and 16% sodium chloride aqueous solution (1:1.2, v/v) was introduced for low toxicity and favorable resolution. In addition, by applying the stop-and-go flow technique, effluents pre-fractionated by CCC was further purified by a preparative column packed with octadecyl silane (ODS) as the second dimension. The interface between the two dimensions was comprised of a 6-port switching valve and an electronically controlled 2-position 10-port switching valve connected with two equivalent holding columns. To be highlighted here, this rationally designed interface for the purpose of smooth desalination, absorption and desorption, successfully solved the solvent compatibility problem between the two dimensional separation systems. The present integrated system was successfully applied in a one-step preparative separation and identification of 10 pure compounds from the water extracts of Tieguanyin tea (Chinese oolong tea). In short, all the results demonstrated that the on-line 2D CCC×LC method is an efficient and green approach for harvesting polar targets in a single step, which showed great promise in drug discovery.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Distribuição Contracorrente/métodos , Extratos Vegetais/química , Polifenóis/isolamento & purificação , Chá/química , Polifenóis/análise , Polifenóis/química , Reprodutibilidade dos Testes
12.
Biol Trace Elem Res ; 160(2): 258-67, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24962641

RESUMO

Studies have shown that men and women exhibit significant differences regarding iron status. However, the effects of sex on iron accumulation and distribution are not well established. In this study, female and male Sprague-Dawley rats were killed at 4 months of age. Blood samples were analyzed to determine the red blood cell (RBC) count, hemoglobin (Hb) concentration, hematocrit (Hct), and mean red blood cell volume (MCV). The serum samples were analyzed to determine the concentrations of serum iron (SI), transferrin saturation (TS), ferritin, soluble transferrin receptor (sTfR), and erythropoietin (EPO). The tissue nonheme iron concentrations were measured in the liver, spleen, bone marrow, kidney, heart, gastrocnemius, duodenal epithelium, lung, pallium, cerebellum, hippocampus, and striatum. Hepatic hepcidin expression was detected by real-time PCR analysis. The synthesis of ferroportin 1 (FPN1) in the liver, spleen, kidney, and bone marrow was determined by Western blot analysis. The synthesis of duodenal cytochrome B561 (DcytB), divalent metal transporter 1 (DMT1), FPN1, hephaestin (HP) in the duodenal epithelium was also measured by Western blot analysis. The results showed that the RBC, Hb, and Hct in male rats were higher than those in female rats. The SI and plasma TS levels were lower in male rats than in female rats. The levels of serum ferritin and sTfR were higher in male rats than in female rats. The EPO levels in male rats were lower than that in female rats. The nonheme iron contents in the liver, spleen, bone marrow, and kidney in male rats were also lower (56.7, 73.2, 60.6, and 61.4 % of female rats, respectively). Nonheme iron concentrations in the heart, gastrocnemius, duodenal epithelium, lung, and brain were similar in rats of both sexes. A moderate decrease in hepatic hepcidin mRNA content was also observed in male rats (to 56.0 % of female rats). The levels of FPN1 protein in the liver, spleen, and kidney were higher in male rats than in female rats. There was no significant change in FPN1 expression in bone marrow. Significant difference was also not found in DcytB, DMT1, FPN1, and HP protein levels in the duodenal epithelium between male and female rats. These data suggest that iron is distributed differently in male and female rats. This difference in iron distribution may be associated with the difference in the hepcidin level.


Assuntos
Perfilação da Expressão Gênica , Hepcidinas/genética , Ferro/sangue , Fígado/metabolismo , Animais , Western Blotting , Medula Óssea/metabolismo , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Grupo dos Citocromos b/genética , Grupo dos Citocromos b/metabolismo , Contagem de Eritrócitos , Eritropoetina/sangue , Eritropoetina/metabolismo , Feminino , Ferritinas/sangue , Ferritinas/metabolismo , Hematócrito , Hemoglobinas/metabolismo , Hepcidinas/metabolismo , Ferro/metabolismo , Rim/metabolismo , Masculino , Ratos Sprague-Dawley , Receptores da Transferrina/sangue , Receptores da Transferrina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores Sexuais , Baço/metabolismo
13.
FEBS Lett ; 588(17): 3259-64, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-25064840

RESUMO

The known functions of type II thioesterases (TEIIs) in type I polyketide synthases (PKSs) include selecting of starter acyl units, removal of aberrant extender acyl units, releasing of final products, and dehydration of polyketide intermediates. In this study, we characterized two TEIIs (ScnI and PKSIaTEII) from Streptomyces chattanoogensis L10. Deletion of scnI in S. chattanoogensis L10 decreased the natamycin production by about 43%. Both ScnI and PKSIaTEII could remove acyl units from the acyl carrier proteins (ACPs) involved in the natamycin biosynthesis. Our results show that the TEII could play important roles in both the initiation step and the elongation steps of a polyketide biosynthesis; the intracellular TEIIs involved in different biosynthetic pathways could complement each other.


Assuntos
Ácido Graxo Sintases/metabolismo , Natamicina/biossíntese , Streptomyces/metabolismo , Tioléster Hidrolases/metabolismo , Sequência de Aminoácidos , Arginina/metabolismo , Ácido Graxo Sintases/química , Espaço Intracelular/enzimologia , Dados de Sequência Molecular , Streptomyces/citologia , Streptomyces/enzimologia , Tioléster Hidrolases/química
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