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1.
Metabolomics ; 20(3): 57, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773045

RESUMEN

BACKGROUND: Despite the clear clinical diagnostic criteria for necrozoospermia in andrology, the fundamental mechanisms underlying it remain elusive. This study aims to profile the lipid composition in seminal plasma systematically and to ascertain the potential of lipid biomarkers in the accurate diagnosis of necrozoospermia. It also evaluates the efficacy of a lipidomics-based random forest algorithm model in identifying necrozoospermia. METHODS: Seminal plasma samples were collected from patients diagnosed with necrozoospermia (n = 28) and normozoospermia (n = 28). Liquid chromatography-mass spectrometry (LC-MS) was used to perform lipidomic analysis and identify the underlying biomarkers. A lipid functional enrichment analysis was conducted using the LION lipid ontology database. The top 100 differentially significant lipids were subjected to lipid biomarker examination through random forest machine learning model. RESULTS: Lipidomic analysis identified 46 lipid classes comprising 1267 lipid metabolites in seminal plasma. The top five enriched lipid functions as follows: fatty acid (FA) with ≤ 18 carbons, FA with 16-18 carbons, monounsaturated FA, FA with 18 carbons, and FA with 16 carbons. The top 100 differentially significant lipids were subjected to machine learning analysis and identified 20 feature lipids. The random forest model identified lipids with an area under the curve > 0.8, including LPE(20:4) and TG(4:0_14:1_16:0). CONCLUSIONS: LPE(20:4) and TG(4:0_14:1_16:0), were identified as differential lipids for necrozoospermia. Seminal plasma lipidomic analysis could provide valuable biochemical information for the diagnosis of necrozoospermia, and its combination with conventional sperm analysis may improve the accuracy and reliability of the diagnosis.


Asunto(s)
Algoritmos , Lipidómica , Semen , Adulto , Humanos , Masculino , Biomarcadores/sangre , Infertilidad Masculina/diagnóstico , Infertilidad Masculina/metabolismo , Lipidómica/métodos , Lípidos/análisis , Lípidos/sangre , Aprendizaje Automático , Bosques Aleatorios , Semen/metabolismo , Semen/química , Cromatografía Líquida con Espectrometría de Masas
2.
Sensors (Basel) ; 23(16)2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37631718

RESUMEN

Aiming at the problem of large measurement error and phase shift in resistance voltage dividers under high-frequency conditions in the field of power measurement, such as power harmonics, an error correction method is proposed for an alternating current (AC) resistance voltage divider based on the equivalence principle. Firstly, the frequency error model of the AC resistance voltage divider precision is established, and the angle difference of the continuous spectrum ratio difference from 50 Hz to 100 kHz is corrected by determining the shielding structure and the resistance parameters and fine-tuning the shielding potential correction method to reduce the capacities error of the AC resistance voltage divider design precision. At the same time, the performance parameters such as the direction and magnitude of the shielding potential compensation capacitive error are investigated. Finally, the precision voltage divider (the maximum voltage applied is 480 V) calibration experiments verify that the important characteristic judgment factor of the voltage divider is independent of the frequency and the equivalent capacitance value, which effectively solves the phase correction problem of harmonic power measurement.

3.
Sensors (Basel) ; 23(9)2023 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-37177416

RESUMEN

Early seismic prediction in tunnels has become a necessary task to prevent construction risks. The type and performance of the seismic source are crucial factors that affect its efficiency and prediction accuracy. Among the existing main types of tunnel seismic sources, both explosive and spark sources require pre-drilling and pose safety hazards. In addition, explosive sources pose a risk of damage to tunnel structure walls. Spark sources must be used in a water medium. Artificial hammer sources have weak energy and short prediction distance. This paper proposes a portable tunnel electromagnetic impulse shock source that overcomes the deficiencies of the aforementioned seismic sources. This paper elaborates on the design and working principle of the electromagnetic impulse shock source, and analyzes the electromagnetic force exerted on the hammer body during acceleration. Through finite element simulation, this paper analyzes the multi-physical field changes of the entire electromagnetic acceleration system. Meanwhile, combining experimental testing, the design parameters and energy of the seismic source are optimized to finally design a portable electromagnetic impulse shock source. The engineering measurement data results show that the seismic source can stably generate an output energy of 1500 J, and the overall weight of the seismic source does not exceed 40 kg, with a single shot time less than 30 s and an effective prediction distance over 100 m. This work has significant practical value and superiority.

4.
Sensors (Basel) ; 23(24)2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38139617

RESUMEN

This paper proposes a nondestructive, separate transmitter-receiver (TX-RX) electromagnetic measurement system for near-surface detection. Different from the traditional dual-coil integrated design, the proposed transient electromagnetic (TEM) system performs shallow subsurface detection using independent TX coil and movable RX coils. This configuration requires a large primary field so that the far-away secondary field is able to generate reliably induced voltages. To achieve this goal, a bipolar current-pulsed power supply (BCPPS) with a late resonant charging strategy is designed to produce a sufficiently large magnetic moment for the exciting coil with low source interference. The magnetic dipole source (MDS) with a large proportion of weight is separated from the field observation device and does not need to be dragged or transported during the detection process. This setup lowers the weight of the scanning device to 3 kg and greatly improves the measurement efficiency. The results of the laboratory test verify the effectiveness of the separate MDS and RX module system. Field experimental detection further demonstrates that the proposed system can realize highly efficient and shallow surface detection within a 200 m range of the MDS device.

5.
Sensors (Basel) ; 22(2)2022 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-35062572

RESUMEN

The pulsed eddy current (PEC) inspection is considered a versatile non-destructive evaluation technique, and it is widely used in metal thickness quantifications for structural health monitoring and target recognition. However, for non-ferromagnetic conductors covered with non-uniform thick insulating layers, there are still deficiencies in the current schemes. The main purpose of this study is to find an effective feature, to measure wall thinning under the large lift-off variations, and further expand application of the PEC technology. Therefore, a novel method named the dynamic apparent time constant (D-ATC) is proposed based on the coil-coupling model. It associates the dynamic behavior of the induced eddy current with the geometric dimensions of the non-ferromagnetic metallic component by the time and amplitude features of the D-ATC curve. Numeral calculations and experiments show that the time signature is immune to large lift-off variations.

6.
Sensors (Basel) ; 20(2)2020 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-31963491

RESUMEN

As an electromagnetic field conversion tool in the transient electromagnetic method (TEM), the weak coupling coils reduce the mutual inductance of its transmitter and receiver coils by special structural optimization, so the detection signal can be protruded from the primary field interference generated by the transmitter coil; thus, this kind of coil design can significantly improve the signal-to-noise ratio. However, with the popularity of drag or aerial TEM exploration, the structural stability problem caused by bumps or windage leads to non-negligible primary field leakages, thereby reducing the detection reliability. This paper incorporates the primary field shielding stability as a key indicator of the weak coupling designs and proposes a calibration scheme for this stability assessment, based on which the shielding stability of five typical weak coupling coil designs is quantitatively compared, and the relationship between the primary field density and the shielding stability explored in this study may contribute to the selection and improvement of TEM coils.

7.
Sensors (Basel) ; 19(16)2019 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-31443286

RESUMEN

The multi-coil sensor consisting of a series of sub-coils provides a reliable way to avoid signal distortion from excitation field. Compared with conventional coil sensors, the multi-coil sensor exhibits more complex signal conversion performance, and the conventional equivalent circuit cannot reveal the possible attenuated oscillation, which seriously degrades the detection reliability. Based on a novel equivalent circuit model, this research investigates the causes of signal oscillation and proposes and validates an effective solution, which contributes to the signal transmission characteristics of multi-coil sensors for engineering applications.

8.
Sensors (Basel) ; 19(5)2019 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-30871052

RESUMEN

Seismic imaging is the most effective geophysical method and has been extensively implemented to detect potential geological hazards in tunnels during construction. The coupling of geophones and the design of geometry in tunnels are the two major challenges. To ensure successful coupling, a high-sensitivity semi-automatic coupling geophone with a broadband was designed. In practice, this geophone is attached with a wheel and two springs. Once inserted into the borehole, an automatic coupling action occurs. This semi-automatic coupling design within the geophone not only guarantees good coupling, but reduces the time and costs usually required to install a traditional geophone. In the use of geophones for tunnel seismic detection, we propose two new two-dimensional (2D) seismic geometries based on the two commonly used geometries. A test to assess the effectiveness of the qualities of imaging from four geometries was completed by comparing the results of the forward modeling of sandwich models. The conclusion is that the larger the horizontal offset of the layout geometry, the higher the resolution of the imaging; the larger the vertical offset, the weaker the mirror image. The vertical offset is limited due to the narrow tunnel condition. Therefore, the mirror effect cannot be entirely eliminated; however, it can be further suppressed by constructing 2D geometry. The two newly proposed 2D geometries caused the imaging arc of the inter-layer, but suppressed the mirror image. The mirror image added a significant number of errors to the data, which could misguide tunnel construction; therefore the new 2D geometries are more reasonable than the two most commonly used. We applied one of the two new 2D geometries that was more practical to an actual project, the Chongqing Jinyunshan Tunnel in China, and acquired high-quality seismic data using two semi-automatic coupling geophones. The detection results were essentially consistent with the excavation conclusions.

9.
Sensors (Basel) ; 19(9)2019 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-31052490

RESUMEN

The grounding grid is critical to the safety and stability of a power system. Corrosive cracking of the grounding conductor is the main cause of deterioration of grounding grid performance. Existing fault diagnosis methods for grounding grids are limited by the number and distribution of grounding leads, and some of them cannot be used for online detection. This paper proposes a grounding grid detection method based on magnetic source excitation. The measuring device consists of four coils, two horizontal excitation coils, and two vertical receiving coils. The secondary magnetic field signal is extracted from the primary field and the background field by properly positioning the coils, such that the measured signal can reflect the underground media more accurately. The measuring device of the method is portable, the measurement process is contactless with the grounding grid, and it is not limited by the grounding leads. Furthermore, it has a strong anti-interference ability and can realize online detection. It was proven by simulations and experiments that the proposed method has a higher measurement accuracy and stronger anti-interference ability when compared with existing methods. This paper also discusses the influence of various factors such as the number and the location of the breakpoints, the frequency of the excitation source, the soil resistivity, and stratification from the measurement data. It was proven that the method has high precision and a wide application range, and is important for guiding significance and reference value in engineering applications.

10.
Sensors (Basel) ; 19(17)2019 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-31470534

RESUMEN

The tunnel seismic method allows for the detection of the geology in front of a tunnel face for the safety of tunnel construction. Conventional geophones have problems such as a narrow spectral width, low sensitivity, and poor coupling with the tunnel wall. To tackle issues above, we propose a semi-automatic coupling geophone equipped with a piezoelectric sensor with a spectral range of 10-5000 Hz and a sensitivity of 2.8 V/g. After the geophone was manually pushed into the borehole, it automatically coupled with the tunnel wall under the pressure of the springs within the device. A comparative experiment showed that the data spectrum acquired by the semi-automatic coupling geophone was much higher than that of the conventional geophone equipped with the same piezoelectric sensor. The seismic data were processed in combination with forward modeling. The imaging results also show that the data acquired by the semi-automatic coupling geophone were more in line with the actual geological conditions. In addition, the semi-automatic coupling geophone's installation requires a lower amount of time and cost. In summary, the semi-automatic coupling geophone is able to efficiently acquire seismic data with high fidelity, which can provide a reference for tunnel construction safety.

11.
Biotechnol Bioeng ; 113(12): 2597-2604, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27241235

RESUMEN

Medium-chain fatty acids (MCFA, e.g., caproic, heptanoic, caprylic acid) are more valuable than short-chain fatty acids (SCFA, e.g., acetic, propionic, butyric, valeric acid). SCFAs are major products in methane-inhibited mixed-culture anaerobic fermentation. By feeding ethanol to the fermentor, MCFA formation is enhanced through chain elongation. Microorganisms such as Clostridium kluyveri elongate short-chain acids by combining them with alcohol. Very low ethanol concentration reduces chain elongation rates, whereas very high ethanol concentrations inhibit microorganisms. To maximize MCFA production, different ethanol concentrations were investigated in the mixed-culture fermentation of office paper and chicken manure. At 10 g/L ethanol concentration, 10 g/L MCFA was formed. High ethanol concentrations (above 40 g/L) inhibit microorganisms resulting in no chain elongation. For chain elongation, propanol was found to be more inhibitory than ethanol. The data suggest that MCFA production will increase by continuously extracting MCFA and maintaining 5-10 g/L ethanol concentration by periodic addition. Biotechnol. Bioeng. 2016;113: 2597-2604. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Celulosa/metabolismo , Etanol/metabolismo , Ácidos Grasos/biosíntesis , Sedimentos Geológicos/microbiología , Estiércol/microbiología , Papel , Animales , Reactores Biológicos/microbiología , Pollos , Medios de Cultivo/química , Medios de Cultivo/metabolismo , Etanol/administración & dosificación , Ácidos Grasos/química , Fermentación/fisiología
12.
Pak J Pharm Sci ; 29(6 Spec): 2207-2212, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28412681

RESUMEN

To explore in vitro release rules of isoniazid (INH) when Isoniazid Super paramagnetic Iron Oxide Microspheres (ISPIOM) are subject to no external magnetic field, applied mechanical magnetic field and scillating magnetic field. ISPIOM was prepared by using the spray drying method; Isoniazid contented in the microspheres was determined, the drug loading capacity and encapsulation efficiency were calculated. Release of isoniazid in the microspheres was determined respectively under the effect of no external magnetic field, applied mechanical magnetic field and oscillating magnetic field, to explore the release rules. In solution with pH=7.4 PBS, microspheres featured 8-hour sustained release under the effect of magnetic field, the released rate of the microspheres is accelerated,. In solution with pH=3 PBS, microspheres release faster and could realize the fastest completion of release in 2 hours under the effect of oscillating magnetic field. To join the external magnetic field in different point time to can't affect the release, under pH=3 of medium, ISPIOM release faster; under the effect of magnetic field, the released rate of the microspheres is accelerated, and the longer effect of magnetic field, the faster release. Oscillating magnetic field can make ISPIOM within a certain period of time, get ideal release curve, so as to achieve good control release effect.

13.
J Health Popul Nutr ; 42(1): 63, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37420277

RESUMEN

BACKGROUND: The elevated circulating toxins secondary to the impairment of intestinal barrier integrity commonly elicit a chronic inflammatory response and finally contribute to multiple diseases. These toxins, including bacterial by-products and heavy metals, are the potent risk factors for the development of recurrent spontaneous abortion (RSA). Preclinical evidence suggests that several dietary fibers can restore intestinal barrier function and decrease the accumulation of heavy metals. However, it is uncertain whether treatment with a newly developed blend of dietary fibers product (Holofood) benefits patients with RSA. METHODS: In this trial, we enrolled 70 adult women with RSA, who were randomly assigned into the experiment group and the control group in a 2:1 ratio. Upon the basis of conventional therapy, subjects in the experiment group (n = 48) received 8 weeks oral administration with Holofood three times daily at a dose of 10 g each time. Subjects without Holofood consumption were set as the control (n = 22). Blood samples were collected for the determinations of metabolic parameters, heavy mental lead, and the indices related to intestinal barrier integrity (D-lactate, bacterial endotoxin, and diamine oxidase activity). RESULTS: The reduction amplitude in blood lead from baseline to week 8 was 40.50 ± 54.28 (µg/L) in the experiment group as compared with 13.35 ± 36.81 (µg/L) in the control group (P = 0.037). The decreased level of serum D-lactate from baseline to week 8 was 5.58 ± 6.09 (mg/L) in the experiment group as compared with - 2.38 ± 8.90 (mg/L, P < 0.0001) in the control group. The change in serum DAO activity from baseline to week 8 was 3.26 ± 2.23 (U/L) in the experiment group as compared with - 1.24 ± 2.22 (U/L, P < 0.0001) in the control group. Participants who received Holofood had a greater decline in blood endotoxin from baseline to week 8 than those in the control group. Moreover, by comparing with the self-baseline, Holofood consumption significantly decreased the blood levels of lead, D-lactate, bacterial endotoxin, and DAO activity. CONCLUSION: Our results suggest that Holofood affords a clinically relevant improvements in blood lead level and intestinal barrier dysfunction in patients with RSA.


Asunto(s)
Aborto Espontáneo , Plomo , Humanos , Adulto , Femenino , Embarazo , Plomo/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Aborto Espontáneo/metabolismo , Endotoxinas/metabolismo , Fibras de la Dieta/uso terapéutico , Fibras de la Dieta/metabolismo , Ácido Láctico/metabolismo
14.
Am J Obstet Gynecol ; 207(6): 511.e1-7, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23099193

RESUMEN

OBJECTIVE: The purpose of this study was to assess the receptivity of the homogeneous endometrium in the late follicular phase in infertile women with natural cycles. STUDY DESIGN: Twenty-eight infertile women with ultrasonographically homogeneous (group 1) or trilaminar (group 2) endometria in the late follicular phase underwent endometrial biopsies. Some molecular markers and development of pinopodes were evaluated. RESULTS: In the late follicular phase, the mean level of vascular endothelial growth factor was significantly lower in group 1 than in group 2 (0.96 ± 0.37 marks vs 1.39 ± 0.46 marks; P = .010). In the mid luteal phase, a decreased leukemia inhibitory factor and integrin alpha v beta 3 levels were found in group 1 (1.58 ± 0.99 marks vs 2.59 ± 0.61 marks; 1.85 ± 0.72 marks vs 2.60 ± 0.73 marks; 1.92 ± 0.91 marks vs 2.83 ± 0.57 marks; P = .003; P = .011; P = .004). The rate of fully developed pinopodes in the mid luteal phase was significantly decreased in group 1 (P = .018). CONCLUSION: An ultrasonographically homogeneous endometrium in the late follicular phase was associated with poor receptivity in infertile women with natural cycles.


Asunto(s)
Endometrio/diagnóstico por imagen , Fase Folicular , Infertilidad Femenina/sangre , Factor Inhibidor de Leucemia/sangre , Fase Luteínica , Factor A de Crecimiento Endotelial Vascular/metabolismo , Adulto , Biopsia , Endometrio/fisiopatología , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Factor Inhibidor de Leucemia/genética , Microscopía Electrónica de Rastreo , Ultrasonografía , Factor A de Crecimiento Endotelial Vascular/genética
15.
Am J Obstet Gynecol ; 204(1): 61.e1-6, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20934676

RESUMEN

OBJECTIVE: We sought to investigate the effectiveness of repeated transvaginal ultrasound-guided aspiration of endometriomas in infertile women with endometriosis. STUDY DESIGN: A retrospective study was performed in our department of reproductive health on 129 infertile women who underwent monthly repeated transvaginal aspiration of endometriomas. The recurrence and pregnancy were monitored during a follow-up period of 24 months. RESULTS: Recurrences of cysts were found in 118 (91.5%) patients in the first postaspirate month and 86 (66.7%) in the second, 60 (46.5%) in the third, 28 (21.7%) in the fourth, 12 (9.3%) in the fifth, 7 (5.4%) in the sixth, and 36 (27.9%) in the 24th postaspiration month. Mean 3.1 ± 2.8 times of aspirations per patient were performed without any adverse effect. There was a linear regression relationship between the change of times of aspirations and the chance of recurrence of cysts. Overall pregnancy rate of 43.4% (56/129) was obtained. CONCLUSION: The repetitive aspiration of endometriomas is an effective therapeutic option in patients with endometriosis.


Asunto(s)
Endometriosis/cirugía , Enfermedades del Ovario/cirugía , Ultrasonografía Intervencional/métodos , Adulto , Endometriosis/diagnóstico por imagen , Femenino , Humanos , Infertilidad Femenina/cirugía , Modelos Lineales , Quistes Ováricos/diagnóstico por imagen , Quistes Ováricos/cirugía , Enfermedades del Ovario/diagnóstico por imagen , Embarazo , Índice de Embarazo , Recurrencia , Reoperación/métodos , Estudios Retrospectivos , Succión/métodos
16.
Appl Microbiol Biotechnol ; 90(5): 1669-79, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21365471

RESUMEN

Wet storage and in situ lime pretreatment (50 °C, 1-atm air, 56 days, excess lime loading of 0.3 g Ca(OH)(2)/g dry biomass) of sugarcane bagasse (4,000 g dry weight) was performed in a bench-scale pile pretreatment system. Under thermophilic conditions (55 °C, NH(4)HCO(3) buffer, methane inhibitors), air-lime-treated bagasse (80 wt.%) and chicken manure (20 wt.%) were anaerobically co-digested in 1-L rotary fermentors by a mixed culture of marine microorganisms (Galveston, TX). During four-stage countercurrent fermentation, the resulting carboxylic acids consisted of primarily acetate (average 87.7 wt.%) and butyrate (average 9.0 wt.%). The experimental fermentation trains had the highest yield (0.47 g total acids/g volatile solids (VS) fed) and highest selectivity (0.79 g total acids/g VS digested) at a total acid concentration of 28.3 g/L, which is equivalent to an ethanol yield of 105.2 gal/(tonne VS fed). Both high total acid concentrations (>44.7 g/L) and high substrate conversions (>77.5%) are predicted for countercurrent fermentations of bagasse at commercial scale, allowing for an efficient conversion of air-lime-treated biomass to liquid transportation fuels and chemicals via the carboxylate platform.


Asunto(s)
Bacterias/metabolismo , Biotecnología/métodos , Ácidos Carboxílicos/metabolismo , Celulosa/metabolismo , Saccharum/microbiología , Anaerobiosis , Compuestos de Calcio/química , Fermentación , Calor , Óxidos/química , Saccharum/metabolismo , Agua de Mar/microbiología
17.
Biotechnol Bioeng ; 106(2): 216-27, 2010 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-20091732

RESUMEN

The MixAlco process is an example of consolidated bioprocessing (CBP) in which anaerobic mixed-culture fermentation biochemically converts any biodegradable feedstock into carboxylate salts. Downstream processing thermochemically transforms the resulting salts into mixed alcohol fuels or gasoline. To enhance digestibility, sugarcane bagasse was treated under mild conditions (55 degrees C, 24 h, and 30% aqueous ammonia solution with a loading of 10 mL/g dry biomass). Using NH(4)HCO(3) buffer, the feedstock (80% ammonia-treated sugarcane bagasse/20% chicken manure) was anaerobically fermented by a mixed culture of marine microorganisms at 55 degrees C. Four-stage countercurrent fermentations were performed at various volatile solids loading rates (VSLRs) and liquid residence times (LRTs). The highest acid productivity (1.14 g/(L day)) occurred at a total acid concentration of 29.8 g/L. The highest conversion (65%) occurred at a total acid concentration of 27.6 g/L. The continuum particle distribution model (CPDM) predicted the experimental total acid concentrations and conversions within 4.98% and 10.41%, respectively. When using NH(4)HCO(3) buffer, ammonia pretreatment is an attractive option. The CPDM "map" shows that both high volatile solid conversions (78.8%) and high acid concentrations (32.6 g/L) are possible with 300 g/(L liquid) substrate concentration, 30 days LRT, 2 g/(L day) solid loading rate and NH(4)HCO(3) buffer.


Asunto(s)
Amoníaco/química , Bacterias Anaerobias/fisiología , Reactores Biológicos/microbiología , Celulosa/metabolismo , Saccharum/química , Saccharum/microbiología , Agua/química , Celulosa/química
18.
Zhonghua Nan Ke Xue ; 16(6): 516-9, 2010 Jun.
Artículo en Zh | MEDLINE | ID: mdl-20608355

RESUMEN

OBJECTIVE: Germ cells are much more susceptible to oxidative stress than somatic cells. Accumulating evidence indicates that uncoupling protein 2 (UCP2) prevents the apoptosis of multiple types of cells induced by reactive oxygen species (ROS). The present study aimed to evaluate the protective effect of uncoupling protein 2 (UCP2) against oxidative damage to human sperm. METHODS: Semen parameters were obtained from 97 semen samples by computer assisted sperm analysis (CASA), and the samples, based on the percentage of grade a + b sperm, allotted to Groups I (n = 25, grade a + b sperm > 50%), II (n = 24, grade a + b sperm 25%-50%), III (n = 24, grade a + b sperm 10-25%) and IV (n = 24, grade a + b sperm < 10%). The expressions of sperm UCP2 mRNA was detected by RT-PCR, and the malonaldehyde (MDA) content in ROS was determined in the sperm suspension. RESULTS: The expressions of UCP2 mRNA in sperm were 1.51 +/- 0.24, 1.28 +/- 0.15, 1.17 +/- 0.20 and 0.69 +/- 0.18, and the MDA contents were (14.66 +/- 2.55), (16.00 +/- 2.09), (17.44 +/- 1.40) and (21.20 +/- 3.50) nmol/10(8) sperm in Groups I, II, III and lV, respectively. There was a significant negative correlation between the expression of UCP2 mRNA and the content of MDA (r = -0.633, P < 0.01), the former obviously reduced while the latter remarkably increased in the groups of lower sperm motility (P < 0.01). CONCLUSION: UCP2 plays an important protective role against oxidative stress damage to human sperm by diminishing ROS production.


Asunto(s)
Canales Iónicos/metabolismo , Proteínas Mitocondriales/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Espermatozoides/metabolismo , Adulto , Humanos , Masculino , Persona de Mediana Edad , Recuento de Espermatozoides , Motilidad Espermática , Proteína Desacopladora 2
19.
Zhonghua Fu Chan Ke Za Zhi ; 44(1): 27-31, 2009 Jan.
Artículo en Zh | MEDLINE | ID: mdl-19563059

RESUMEN

OBJECTIVE: To evaluate the clinical and endocrine effectiveness of different laser doses for ultrasound-guided transvaginal ovarian interstitial laser treatment in patients with polycystic ovary syndrome (PCOS). METHODS: Between January 2005 and July 2007, 56 women with clomifene citrate-resistant PCOS selected from the patients who were referred to Shenzhen Maternity and Child Healthcare Hospital with a request for fertility underwent ultrasound-guided transvaginal ovarian interstitial laser treatment. All subjects were randomly divided into four groups of A, B, C and D. In group A, one coagulation point per ovary was done and group B, two points; group C, three points; group D, four to five points. The size of each point was about 10 mm in diameter (the electrical laser was projected persistently for 1-3 min with a power of 3 -5 W). The serum sexual hormone level, ovulation rate and pregnancy rate within six postoperative months were compared among the four groups. RESULTS: (1) The spontaneous ovulation rates of groups A (0) and B (21%) within six postoperative months were significantly lower than groups C (71% ,P <0. 05) and D (79%, P < 0.01). The accumulative pregnancy rates of group C(43%) and D(36%) for six postoperative months were significantly higher than group A (0; P < 0.01, P < 0.05). Although they were also higher than that of group B, no statistical significance was found (P > 0.05). (2) No statistically significant differences were found among four groups when various preoperative hormone values were compared (P > 0. 05). The mean serum luteinizing hormone (LH), testosterone level and LH/ follicle stimulating hormone (FSH) ratio was significantly lower postoperatively in groups C [(6.3 +/- 2.6) U/L, (2.2 +/- 0.7) nmol/L, 1.1 +/- 0.3] and D [(5.8 +/- 2.5) U/L, (2.1 +/- 0.4) nmol/L, 1.0 +/- 0.4] than in groupsA [(11.9 +/- 3.1) U/L, (3.9 +/- 1.6) nmol/L, 2.1 +/- 0.5] and B [(10.4 +/- 3.9) U/L, (3.3 +/- 1.1) nmol/L, 2.0 +/- 0.6], respectively (P < 0.05). The mean LH, testosterone level and LH/FSH ratio reduced more obviously in groups C (42%, 39% and 42%) and D (53%, 40% and 58%) than in groups A (4%, 9% and 16%) and B (11%, 6% and 5%; P < 0.05). All above-mentioned parameters between groups C and D had no statistical significant difference (P > 0.05). CONCLUSIONS: One and two intraovarian laser coagulation points per ovary are associated with poor results. Three points per ovary seem to represent the plateau of effective dose for the ovarian interstitial laser treatment. Increasing the dose above it does not improve the outcome.


Asunto(s)
Anovulación/cirugía , Infertilidad Femenina/cirugía , Coagulación con Láser/métodos , Síndrome del Ovario Poliquístico/cirugía , Adulto , Anovulación/diagnóstico por imagen , Clomifeno/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Infertilidad Femenina/diagnóstico por imagen , Ovario/diagnóstico por imagen , Ovario/cirugía , Síndrome del Ovario Poliquístico/diagnóstico por imagen , Embarazo , Resultado del Tratamiento , Ultrasonografía Intervencional , Vagina/diagnóstico por imagen , Vagina/cirugía , Adulto Joven
20.
Appl Biochem Biotechnol ; 181(1): 294-308, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27535410

RESUMEN

In rapidly growing developing countries, waste disposal is a major challenge. Current waste disposal methods (e.g., landfills and sewage treatment) incur costs and often are not employed; thus, wastes accumulate in the environment. To address this challenge, it is advantageous to create economic incentives to collect and process wastes. One approach is the MixAlco process, which uses methane-inhibited anaerobic fermentation to convert waste biomass into carboxylate salts, which are chemically converted to industrial chemicals and fuels. In this paper, humanure (raw human feces and urine) is explored as a possible nutrient source for fermentation. This work focuses on fermenting municipal solid waste (energy source) and humanure (nutrient source) in batch fermentations. Using the Continuum Particle Distribution Model (CPDM), the performance of continuous countercurrent fermentation was predicted at different volatile solid loading rates (VSLR) and liquid residence times (LRT). For a four-stage countercurrent fermentation system at VSLR = 4 g/(L∙day), LRT = 30 days, and solids concentration = 100 g/L liquid, the model predicts carboxylic acid concentration of 68 g/L and conversion of 78.5 %.


Asunto(s)
Fermentación , Eliminación de Residuos , Residuos Sólidos , Biomasa , Ácidos Carboxílicos/química , Celulosa/química , Países en Desarrollo , Heces/química , Humanos , Orina/química
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