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1.
Plant Physiol Biochem ; 211: 108677, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38703499

RESUMEN

Phosphorus (P) plays a crucial role in facilitating plant adaptation to cadmium (Cd) stress. However, the molecular mechanisms underlying P-mediated responses to Cd stress in roots remain elusive. This study investigates the effects of P on the growth, physiology, transcriptome, and metabolome of Salix caprea under Cd stress. The results indicate that Cd significantly inhibits plant growth, while sufficient P alleviates this inhibition. Under Cd exposure, P sufficiency resulted in increased Cd accumulation in roots, along with reduced oxidative stress levels (superoxide anion and hydrogen peroxide contents were reduced by 16.8% and 30.1%, respectively). This phenomenon can be attributed to the enhanced activities of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT), as well as increased levels of antioxidants including ascorbic acid (AsA) and flavonoids under sufficient P conditions. A total of 4208 differentially expressed genes (DEGs) and 552 differentially accumulated metabolites (DAMs) were identified in the transcriptomic and metabolomic analyses, with 2596 DEGs and 113 DAMs identified among treatments with different P levels under Cd stress, respectively. Further combined analyses reveal the potential roles of several pathways in P-mediated Cd detoxification, including flavonoid biosynthesis, ascorbate biosynthesis, and plant hormone signal transduction pathways. Notably, sufficient P upregulates the expression of genes including HMA, ZIP, NRAMP and CAX, all predicted to localize to the cell membrane. This may elucidate the heightened Cd accumulation under sufficient P conditions. These findings provide insights into the roles of P in enhancing plant resistance to Cd stress and improving of phytoremediation.


Asunto(s)
Cadmio , Fósforo , Raíces de Plantas , Salix , Transcriptoma , Cadmio/metabolismo , Cadmio/toxicidad , Raíces de Plantas/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , Fósforo/metabolismo , Salix/metabolismo , Salix/genética , Salix/efectos de los fármacos , Transcriptoma/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Metabolómica , Estrés Oxidativo/efectos de los fármacos , Metaboloma/efectos de los fármacos , Antioxidantes/metabolismo , Perfilación de la Expresión Génica
2.
J Affect Disord ; 361: 17-23, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38815765

RESUMEN

BACKGROUND: Depression is linked to obesity. The body roundness index (BRI) provides a more accurate assessment of body and visceral fat levels than the body mass index or waist circumference. However, the association between BRI and depression is unclear. Therefore, we investigated this relationship using the National Health and Nutrition Examination Survey (NHANES) database. METHODS: In this population-based cross-sectional study, data from 18,654 adults aged ≥20 years from the NHANES 2011-2018 were analyzed. Covariates, including age, gender, race/ethnicity, education level, marital status, poverty-income ratio, alcohol status, smoking status, hypertension, diabetes mellitus, cardiovascular disease, energy intake, physical activity, total cholesterol, and triglycerides were adjusted in multivariable logistic regression models. In addition, smooth curve fitting, subgroup analysis, and interaction testing were conducted. RESULTS: After adjusting for covariates, BRI was positively correlated with depression. For each one-unit increase in BRI, the prevalence of depression increased by 8 % (odds ratio = 1.08, 95 % confidence interval = 1.05-1.10, P < 0.001). LIMITATIONS: As this was a cross-sectional study, we could not determine a causal relationship between BRI and depression. Patients with depression in this study were not clinically diagnosed with major depressive disorder. CONCLUSION: BRI levels were positively related to an increased prevalence of depression in American adults. BRI may serve as a simple anthropometric index to predict depression.

4.
J Environ Manage ; 357: 120691, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38554452

RESUMEN

Regions affected by heavy metal contamination frequently encounter phosphorus (P) deficiency. Numerous studies highlight crucial role of P in facilitating cadmium (Cd) accumulation in woody plants. However, the regulatory mechanism by which P affects Cd accumulation in roots remains ambiguous. This study aims to investigate the effects of phosphorus (P) deficiency on Cd accumulation, Cd subcellular distribution, and cell wall components in the roots of Salix caprea under Cd stress. The results revealed that under P deficiency conditions, there was a 35.4% elevation in Cd content in roots, coupled with a 60.1% reduction in Cd content in shoots, compared to the P sufficiency conditions. Under deficient P conditions, the predominant response of roots to Cd exposure was the increased sequestration of Cd in root cell walls. The sequestration of Cd in root cell walls increased from 37.1% under sufficient P conditions to 66.7% under P deficiency, with pectin identified as the primary Cd binding site under both P conditions. Among cell wall components, P deficiency led to a significant 31.7% increase in Cd content within pectin compared to P sufficiency conditions, but did not change the pectin content. Notably, P deficiency significantly increased pectin methylesterase (PME) activity by regulating the expression of PME and PMEI genes, leading to a 10.4% reduction in the degree of pectin methylesterification. This may elucidate the absence of significant changes in pectin content under P deficiency conditions and the concurrent increase in Cd accumulation in pectin. Fourier transform infrared spectroscopy (FTIR) results indicated an increase in carboxyl groups in the root cell walls under P deficiency compared to sufficient P treatment. The results provide deep insights into the mechanisms of higher Cd accumulation in root mediated by P deficiency.


Asunto(s)
Pectinas , Salix , Pectinas/química , Pectinas/metabolismo , Pectinas/farmacología , Cadmio/metabolismo , Salix/metabolismo , Raíces de Plantas/química , Pared Celular/metabolismo , Fósforo/análisis
5.
BMC Psychiatry ; 23(1): 845, 2023 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-37974120

RESUMEN

BACKGROUND: As the most abundant fatty acid in plasma, oleic acid has been found to be associated with multiple neurological diseases; however, results from studies of the relationship between oleic acid and depression are inconsistent. METHODS: This cross-sectional study analyzed 4,459 adults from the National Health and Nutrition Examination Survey 2011-2014. The following covariates were adjusted in multivariable logistic regression models: age, sex, race/ethnicity, education level, marital status, body mass index, physical activity, smoking status, alcohol status, metabolic syndrome, omega-3 polyunsaturated fatty acids, and total cholesterol. RESULTS: Serum oleic acid levels were positively associated with depression. After adjusting for all covariates, for every 1 mmol/L increase in oleic acid levels, the prevalence of depression increased by 40% (unadjusted OR: 1.35, 95%CI: 1.16-1.57; adjusted OR: 1.40, 95% CI: 1.03-1.90). CONCLUSIONS: Our study suggests that oleic acid may play a role in depression. Further research is needed to investigate the potential benefits of changing oleic acid levels for the treatment and prevention of depression.


Asunto(s)
Depresión , Ácidos Grasos Omega-3 , Adulto , Humanos , Estados Unidos/epidemiología , Depresión/epidemiología , Ácido Oléico , Estudios Transversales , Encuestas Nutricionales
6.
BMC Psychiatry ; 23(1): 671, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37715146

RESUMEN

BACKGROUND: Despite the close relationship between sleep-wake cycles and depression symptoms, the relationship between sleep midpoint and depression symptoms in adults remains understudied. METHODS: In this cross-sectional study, 18280 adults aged ≥ 18 years from the National Health and Nutrition Examination Survey (NHANES) 2015-2020 were analyzed. Covariates included age, sex, race/ethnicity, education level, marital status, family income, body mass index, smoking status, drinking status, physical activity, comorbid condition, sleep duration, and sleep disturbance were adjusted in multivariate regression models. RESULTS: Weighted restricted cubic spline based on the complex sampling design of NHANES showed that in participants with a sleep midpoint from 2:18 AM to 6:30 AM, the prevalence of depression symptoms increased by 0.2 times (adjusted odds ratio [OR] = 1.20, 95% confidence interval [CI]: 1.08-1.33) per 1-h increment in sleep midpoint compared to the reference point of 2:18 AM. For participants with a sleep midpoint after 6:30 AM and before 2:18 AM the next day, the relationship between sleep midpoint and depression symptoms was not significant after adjusting for all covariates (adjusted OR = 1.01, 95% CI: 0.99-1.03). CONCLUSIONS: The findings indicate a significant nonlinear association between sleep midpoint and depression symptoms in a nationally representative sample of adults.


Asunto(s)
Depresión , Sueño , Humanos , Adulto , Estudios Transversales , Depresión/epidemiología , Encuestas Nutricionales , Duración del Sueño
7.
Sci Rep ; 13(1): 10220, 2023 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-37353507

RESUMEN

The relationship between current dietary caffeine intake and severe headache or migraine is controversial. Therefore, we investigated the association between dietary caffeine intake and severe headaches or migraines among American adults. This cross-sectional study included 8993 adults (aged ≥ 20 years) with a dietary caffeine intake from the National Health and Nutrition Examination Surveys of America from 1999 to 2004. Covariates, including age, race/ethnicity, body mass index, poverty-income ratio, educational level, marital status, hypertension, cancer, energy intake, protein intake, calcium intake, magnesium intake, iron intake, sodium intake, alcohol status, smoking status, and triglycerides, were adjusted in multivariate logistic regression models. In US adults, after adjusting for potential confounders, a 100 mg/day increase in dietary caffeine intake was associated with a 5% increase in the prevalence of severe headache or migraine (odds ratio [OR] 1.05, 95% confidence interval [CI] 1.02-1.07). Further, the prevalence of severe headache or migraine was 42% higher with caffeine intake of ≥ 400 mg/day than with caffeine intake of ≥ 0 to < 40 mg/day (OR 1.42, 95% CI 1.16-1.75). Conclusively, dietary caffeine intake is positively associated with severe headaches or migraines in US adults.


Asunto(s)
Cafeína , Trastornos Migrañosos , Adulto , Humanos , Estados Unidos/epidemiología , Cafeína/efectos adversos , Estudios Transversales , Trastornos Migrañosos/epidemiología , Encuestas Nutricionales , Cefalea/epidemiología
8.
Ecotoxicol Environ Saf ; 249: 114461, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38321680

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are well known persistent organic pollutants that have carcinogenic, teratogenic, and mutagenic effects on humans and animals. Arbuscular mycorrhizal fungi (AMF) that can infest plant hosts and form symbioses may help plants to enhance potential rhizosphere effects, thus contributing to the rhizodegradation of PAH-contaminated soils. The present study aimed to assess the effectiveness of AMF on enhancing Salix viminalis-mediated phytoremediation of PAH-polluted soil and clarify the plant enzymatic and organic acid mechanisms induced by AMF. Natural attenuation (NA), phytoremediation (P, Salix viminalis), S. viminalis-AMF combined remediation using willow inoculated with Funneliformis mosseae (PM), Laroideoglomus etunicatum (PE), and Rhizophagus intraradices (PI) were used as strategies for the remediation of PAH-polluted soils. The results showed that AMF inoculation contributed to the dissipation of the high-molecular-weight PAH benzo (α) pyrene that had concentrations in PM, PE, and PI treatments of 40.1 %, 24.49 %, and 36.28 % of the level in the NA treatment, and 62.32 %, 38.05 %, and 56.38 % of the level in the P treatment after 90 days. The mycorrhizal treatment also improved the removal efficiency of phenanthrene and pyrene, as their concentrations were sharply decreased after 30 days compared to the NA and P treatments. The research further clarified the changes in rhizosphere substances induced by AMF. Organic acids including arachidonic acid, octadecanedioic acid, α-linolenic acid, 10,12,14-octadecarachidonic acid and 5-methoxysalicylic acid that can act as co-metabolic substrates for certain microbial species to metabolize PAHs were significantly increased in AMF-inoculated treatments. AMF inoculation also elevated the levels of polyphenol oxidase, laccase, and dehydrogenase, that played crucial roles in PAHs biodegradation. These findings provide an effective strategy for using AMF-assisted S. viminalis to remediate PAH-polluted soils, and the results have confirmed the key roles of organic acids and soil enzymes in plant-AMF combined remediation of PAHs.


Asunto(s)
Micorrizas , Hidrocarburos Policíclicos Aromáticos , Salix , Contaminantes del Suelo , Animales , Humanos , Micorrizas/metabolismo , Hidrocarburos Policíclicos Aromáticos/análisis , Biodegradación Ambiental , Salix/metabolismo , Suelo , Pirenos/metabolismo , Contaminantes del Suelo/análisis , Raíces de Plantas/metabolismo
9.
Front Nutr ; 9: 983511, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36159493

RESUMEN

Depressive symptoms are major public health problems. Leisure-time Physical activity (LPA) and dietary inflammatory preference are emerging factors that tends to affect the mental health status. There is limited evidence regarding the joint influence of LPA and dietary status on the prevalence of depression. This study was a cross-sectional study, which used a nationwide represented sample from the National Health and Nutrition Examination Survey (NHANES) to assess the relationship among LPA, diet status and depression. Depression and LPA status was reported by the 9-item Patient Health Questionnaire (PHQ-9) and Physical Activity Questionnaire (PAQ), respectively. To assess dietary inflammatory preferences, dietary inflammatory index (DII) was applied based on a 24-h dietary recall interview. A total of 11,078 subjects was included in this study and weighted participants were 89,682,020. Weighted multivariable linear regression showed that DII was negatively associated with LPA after full adjustment, with ß (95% CI): -0.487 (-0.647, -0.327). Weighted multivariable logistic regression showed that LPA was significantly associated with depressive symptoms after full adjustment, with odds ratios OR (95% CIs): 0.986 (0.977, 0.995). By DII stratification analysis, this phenomenon was also existed in groups with anti-inflammatory diet. Mediation effect analysis was further performed, which showed that DII significantly mediating the association between LPA and depression with proportion mediated as 3.94%. Our findings indicated the mediating role of DII in the association between LPA condition and incident depression. More well-designed studies are still needed to validate the causal relationship.

10.
Clin Med Insights Oncol ; 16: 11795549221109500, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35875418

RESUMEN

Background: Bone-related extramedullary disease (EMD-B) is mass of clonal plasma cells derived from adjacent bone lesions and has obvious heterogeneities in clinical outcomes. This retrospective study aims to evaluate the treatment outcomes and long-term prognosis of newly diagnosed myeloma patients with EMD-B. Methods: This was a retrospective study conducted in Beijing Chaoyang Hospital from January 1, 2010 to December 31, 2019. Seventy-seven newly diagnosed multiple myeloma patients with EMD-B were selected. Propensity score matching (1:2) was used to match patients with and without EMD-B. After matching, 132 patients without extramedullary disease (non-EMD) were included in the study. All patients received bortezomib-based regimens as induction therapy. Results: After matching, baseline data of the 2 groups were comparable. The Cox regression analysis of patients with EMD-B showed that age, paravertebral lesions, and immunoglobulin D (IgD) type may have adverse effects on survival. Bone-related extramedullary disease at new diagnosis was a risk predictor of survival (hazard ration [HR] = 1.80, 95% confidence interval [CI]: 1.09-2.98, P = .022). The median survival time of the EMD-B group was significantly shorter than that of the non-EMD group (52 months vs 96 months, P = .043). Induction therapy did not show any significant differences in effectiveness between the 2 groups. Autologous stem cell transplantation (ASCT) significantly increased complete remission rate of patients with EMD-B (EMD-B vs non-EMD: no ASCT 15.7% vs 31.9%, P = .035; ASCT 42.3% vs 48.8%, P = .626) and improved their median overall survival rate (EMD-B vs non-EMD: no ASCT 49 months vs 75 months, P = .003; ASCT not reached vs 96 months, P = .505). Conclusions: This study demonstrated that newly diagnosed myeloma patients with EMD-B had poor outcomes, which could be improved by ASCT.

11.
Mol Med Rep ; 24(4)2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34414446

RESUMEN

Cell therapy is a promising treatment strategy for patients with type 1 diabetes. Porcine pancreas­derived mesenchymal stromal cells (PMSCs) have emerged as one of the most widely used cell resources owing to their high proliferative capacity and multi­lineage differentiation potential. Although the induction efficiency and insulin production of induced insulin­producing cells (IPCs) derived from PMSCs have been estimated, these have primarily focused on the function of induced cells and alterations in related gene expression levels. However, morphological analyses and biological characterization of PMSCs and induced IPCs have not been conducted. Therefore, the present study aimed to optimize an induction protocol, resulting in a 78.92% induction rate. The present study investigated the biological characteristics of PMSCs and optimized a simple but functional three­step protocol to transform PMSCs into IPCs. PMSCs were isolated from 2­3­month­old Bama miniature pig embryos, which were then subcultured to passage 16. The surface markers pancreatic and duodenal homeobox 1, NK6 homeobox 1, Vimentin, Nestin, CD73, CD90, neurogenin 3, CD45 and CD34 were detected by immunofluorescence staining or flow cytometry. Proliferative capacity was evaluated by constructing growth curves of cells at three different passages. Functional differentiation was assessed by morphological observation, dithizone staining, and immunofluorescence staining of C­peptide, insulin, NK6 homeobox 1 and glucagon. The production of insulin by differentiated cells was also analyzed by performing ELISAs. The results demonstrated that differentiated cells were distributed with an islet­like structure, expressed specific markers C­peptide and insulin, and displayed glucose responsiveness. The results of the present study demonstrated that PMSCs were functionally induced into IPCs with the optimized three­step protocol, which may serve as a potential cell therapy strategy to widen the availability and promote the clinical application of cell therapy.


Asunto(s)
Diferenciación Celular , Insulina/metabolismo , Células Madre Mesenquimatosas/metabolismo , Páncreas/metabolismo , Animales , Diferenciación Celular/genética , Tratamiento Basado en Trasplante de Células y Tejidos , Expresión Génica , Glucosa/metabolismo , Células Secretoras de Insulina , Porcinos
12.
Pancreas ; 49(7): 947-954, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32658079

RESUMEN

OBJECTIVES: This study aims to investigate the characteristics of sheep pancreatic mesenchymal stem cells (PSCs) and therapeutic potential of differentiated ß-like cells in streptozotocin-induced diabetic mice. METHODS: Pancreatic mesenchymal stem cells were isolated from 3- to 4-month-old sheep embryos, and their biological characteristics were explored. The function and therapeutic potential of differentiated ß-like insulin-producing cells were also investigated in vitro and in vivo. Differentiated cells were identified through dithizone staining and immunofluorescence staining. Insulin secretion was analyzed using an enzyme-linked immunosorbent assay kit. The preliminary therapeutic potential of induced ß-like cells in diabetic mice was detected by blood glucose and body weight. RESULTS: Primary PSCs were isolated and subcultured up to passage 36. Immunofluorescence staining presented PSC-expressed important markers such as Pdx1, Nkx6-1, Ngn3, and Nestin. Primary PSCs could be induced into functional pancreatic ß-like islet cells with a 3-step protocol. The induced ß-like islet cells could ameliorate blood glucose in diabetic mice. CONCLUSIONS: The method proposed for generating pancreatic islet ß cells provided a preliminary phenotypic investigation of induced cell treatment in diabetic mice, and also laid a foundation in the identification of pharmaceutical targets to treat insulin-dependent diabetes.


Asunto(s)
Diferenciación Celular , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 1/terapia , Células Secretoras de Insulina/citología , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/citología , Animales , Glucemia/metabolismo , Peso Corporal , Péptido C/metabolismo , Células Cultivadas , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Tipo 1/sangre , Glucagón/metabolismo , Glucosa/farmacología , Humanos , Insulina/metabolismo , Secreción de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Masculino , Células Madre Mesenquimatosas/metabolismo , Ratones , Ovinos
13.
Rev Sci Instrum ; 91(5): 056104, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32486737

RESUMEN

A gas switch triggered by µJ laser pulses was developed. The switch employed a 10 mm-gap GaAs photoconductive semiconductor switch (PCSS) mounted in parallel with one of its two gaps. The dark current-voltage characteristic of the PCSS was obtained, and the gas switch characteristics at different bias voltages were experimentally investigated. The results indicate that the switch can be triggered reliably by using a 17 µJ laser pulse, and the jitter is less than 3 ns at the bias voltage of 80 kV and 60% of the self-breakdown voltage.

14.
BMC Urol ; 19(1): 139, 2019 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-31888583

RESUMEN

BACKGROUND: Urolithiasis is a clinically common benign disease in urology. Surgical treatments that are widely used in urolithiasis are percutaneous nephrolithotomy, rigid/flexible ureteroscopy, laparoscopic surgery, and endoscopic combined intrarenal surgery. The da Vinci surgical system is rarely used in the treatment of urolithiasis. In the current study, we report a case of multiple urinary tract calculi treated by robot-assisted laparoendoscopic single-site (RA-LESS) surgery. CASE PRESENTATION: A 49-year-old male patient was admitted to our hospital and diagnosed with multiple urinary tract calculi. He previously underwent right ureterolithotomy, laparoscopic cholecystectomy, and extracorporeal shockwave lithotripsy. Computed tomography (CT) scan and three-dimensional reconstruction CT image showed that multiple calculi were located in the right kidney, right upper ureter, and bladder. The preoperative glomerular filtration rate (GFR) were 17.81 ml/min (right kidney) and 53.11 ml/min (left kidney). We utilized the da Vinci system docking with a single-site port to perform pyelolithotomy, ureterolithotomy, and cystolithotomy, simultaneously. The operative time was 135 min and estimated blood loss was 30 ml. The postoperative hospital stay was 5 days. Three months after surgery, the serum creatinine and urea nitrogen levels dropped to a normal range, and no residual fragments were found in the CT scan. The postoperative GFR were 26.33 ml/min (right kidney) and 55.25 ml/min (left kidney). CONCLUSIONS: RA-LESS surgery is a safe and effective surgical procedure in the treatment of multiple urinary tract calculi; however, further investigation is needed to validate its long-term therapeutic effect.


Asunto(s)
Cálculos Renales/cirugía , Laparoscopía/métodos , Procedimientos Quirúrgicos Robotizados/métodos , Cálculos Ureterales/cirugía , Cálculos de la Vejiga Urinaria/cirugía , Tasa de Filtración Glomerular , Humanos , Cálculos Renales/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Tempo Operativo , Tomografía Computarizada por Rayos X , Cálculos Ureterales/diagnóstico por imagen , Cálculos de la Vejiga Urinaria/diagnóstico por imagen
16.
Rev Sci Instrum ; 89(9): 096105, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30278756

RESUMEN

To reduce the trigger threshold voltage of the multi-gap gas switch used for linear transformer drivers, a method is proposed by mounting resistors and capacitors in parallel with the switch gaps. Based on the circuit model of the six-gap gas switch, the gap voltage distribution during the triggering process is analyzed. When the multi-gap gas switch is triggered, the voltage distribution between gaps is mainly determined by the stray capacitance between electrodes. In such condition, the trigger voltage is not fully applied on the trigger gap, and as a consequence, a higher trigger voltage is required for obtaining a low jitter. The effects of capacitor parameters on the triggering characteristics of the switch are experimentally investigated. Compared with the original switch design, the results indicate that at a charging voltage of ±80 kV and operating at 60% of the self-breakdown voltage, the trigger voltage is reduced from 110 kV to 75 kV while the 3.2 ns jitter of the switch is preserved.

17.
Rev Sci Instrum ; 88(7): 076102, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28764501

RESUMEN

It is difficult to feed the trigger pulse into an electrically triggered mega-volt switch, and the present note presents a novel trigger pulse feed method. The trigger pulse is introduced via a damping resistor, which is mounted between the inner and outer cylindrical electrodes of the pulse transmission line. The mega-volt pulse is damped because the voltage is resistively divided by the resistor and trigger cable arrangement. Both the complex breakdown processes of the switch and its insulation issues are experimentally studied. The function and the beneficial effects of the damping resistor, installed together with an additional inductor, are discussed. Finally, the parameters of these two damping components are set to 500 Ω and 2 µH values for which the switch has been demonstrated to work successfully at over 2.3 MV.

18.
Arch Orthop Trauma Surg ; 131(2): 157-61, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20499244

RESUMEN

A 40-year-old woman had her right extremity avulsed at the proximal upper arm level and the wrist and hand of her left extremity irretrievably injured in a traffic accident. The right distal forearm was surgically amputated and replanted onto the stump of the left distal forearm. New strategy for nerve repair was applied and the function recovery of the cross-replanted hand was favorable. We thought that cross-extremity replantation was indicated when the patient suffered from bilateral total or subtotal amputation at different levels and orthotopic replantation was impossible.


Asunto(s)
Amputación Traumática/cirugía , Traumatismos del Brazo/cirugía , Reimplantación/métodos , Adulto , Femenino , Humanos , Procedimientos Ortopédicos/métodos
19.
Int J Pharm ; 314(1): 46-55, 2006 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-16551494

RESUMEN

Poly(lactic-co-glycolic acid) (PLGA) nanospheres containing protease inhibitors, camostat mesilate (CM) and nafamostat mesilate (NM), were prepared by the emulsion solvent diffusion methods in water or in oil, and the w/o/w emulsion solvent evaporation method. The average diameter of PLGA nanospheres prepared in the water system were about 150-300 nm, whereas those prepared in the oil system were 500-600 nm. Among the three methods, these drugs were the most efficiently encapsulated up to 60-70% in PLGA nanospheres in the oil system. Other factors that may influence drug encapsulation efficiency and in vitro release such as drug load, molecular weight of polymer were also investigated. Both the CM- and NM-loaded nanospheres prepared in the water system immediately released about 85% of the drug upon dispersed in the release medium while the drug initial burst of nanospheres prepared by the emulsion solvent diffusion in oil method reduced to 30% and 60% for CM and NM, respectively. Poly(aspartic acid) (PAA), a complexing agent for cationic water soluble drugs, showed little effect on the encapsulation efficiency and release behavior for CM and NM. The DSC study and AFM pictures of nanospheres demonstrated that temperature-dependent drug release behavior was ascribable to the glass transition temperature of the polymer, which also affected the morphology of nanospheres upon dispersed in the release medium and influenced the drug release consequently.


Asunto(s)
Guanidinas/química , Ácido Láctico/química , Nanotubos/química , Ácido Poliglicólico/química , Polímeros/química , Inhibidores de Proteasas/química , Benzamidinas , Química Farmacéutica , Ésteres , Gabexato/administración & dosificación , Gabexato/análogos & derivados , Gabexato/química , Guanidinas/administración & dosificación , Peso Molecular , Tamaño de la Partícula , Péptidos/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Inhibidores de Proteasas/administración & dosificación , Solubilidad
20.
Chem Pharm Bull (Tokyo) ; 53(8): 893-8, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16079515

RESUMEN

Gabexate mesilate (GM) and camostat mesilate (CM) are protease inhibitors used for the treatment of pancreatitis, and have been reported to show anticancer effects in vivo. Lipid emulsions (20% fractionated soybean oil) were investigated in terms of physicochemical interaction between the drugs and lipid emulsions as a possible drug carrier. The result showed that the drugs did not distribute in the oil phase but were adsorbed at the phospholipid interface of oil droplets. With increasing concentration of the drugs, the adsorption amount at the interface rose steeply to around 2.2x10(-11) mol/cm2 for GM and 1.2x10(-11) mol/cm2 for CM, respectively, followed by further adsorption deviated from the Langmuir adsorption manner after the inflection. To interpret this two-stage adsorption of the drugs, surface potential and fluorescence changes were examined in addition to thermodynamics for their interaction with the interfacial lipid layer. The primary adsorption was exothermic and was due to electrostatic interaction and van der Waals interaction between drug molecules and phospholipid molecules. Both acidic and neutral phospholipids in the lipid were involved in the adsorption of GM, while acidic phospholipids were mainly involved in the adsorption of CM. On the other hand, the secondary adsorption was endothermic and was entropy-driven most probably due to hydrophobic interaction for GM and CM in common, including peripheral penetration of drug molecules into the interfacial lipid layer.


Asunto(s)
Gabexato/análogos & derivados , Gabexato/química , Lípidos/química , Inhibidores de Proteasas/química , Emulsiones , Ésteres , Guanidinas , Espectrometría de Fluorescencia , Termodinámica
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