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Many spheric bodies with radiating, needle-like filaments are present in semen of patients with fertility problems. These bodies are most likely degenerated sperm. The intermediate forms and a sequential series of degeneration are discussed.  相似文献   

3.
In this study we report on magnetic orientation of human sperms. Samples were taken from 17 donors. Normal human sperms became oriented with their long axis perpendicular to the magnetic field (1 T maximum). Total orientation was achieved with magnetic field of about 1 T, while for abnormal sperms the magnetic behavior was different. The dependence of the measured degree of orientation on the intensity of the magnetic field was in good agreement with the theoretical equation for the magnetic orientation of diamagnetic substances. As a result of a numerical analysis based on the equation, the anisotropic diamagnetic susceptibility of normal sperm was found to be Δχ = 8 × 10–20 J/T2. The degree of orientation was influenced by the alterations in the shape of the head, body or the tail. It has been suggested that the DNA in the sperm head retain the strong magnetic anisotropy to counterbalance the magnetic anisotropy retained by flagellum microtubules. Recent studies demonstrated a well‐defined nuclear architecture in human sperm nucleus, where the head morphology has significant correlation with sperm chromatin structure assay SCSA. Then, as the methods to evaluate SCSA can be difficult and expensive our simple magnetic orientation technique can be an alternative to diagnose alteration in DNA. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

4.
An analytical method based on high-performance liquid chromatographic (HPLC) was developed for the determination of montelukast in human plasma using mefenamic acid as an internal standard. After precipitation of plasma proteins with acetonitrile, chromatographic separation was carried out using a Zorbax Eclipse XDB C8 (150 mm x 4.6 mm i.d., 5 microm) with mobile phase consisted of methanol-acetonitrile-0.04M disodium hydrogen orthophosphate (22:22:56, v/v, pH 4.9). The wavelengths of fluorescence detection were set at 350 nm for excitation and 450 nm for emission. The linearity was confirmed in the concentration range of 5-1000 ng/ml in human plasma. Intra- and inter-day accuracy determined from quality control samples were 101.50 and 107.24%, and 97.15 and 100.37%, respectively. Intra- and inter-day precision measured as coefficient of variation were < or =4.72 and < or =9.00%, respectively. Extraction recoveries of drug from plasma were >48.14%. The protocol herein described was employed in a pharmacokinetic study of tablet formulation of montelukast in healthy Thai male volunteers.  相似文献   

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A novel technique is described for assay of aryl hydrocarbon hydroxylase in cultured human lymphocytes. The sensitivity is equal to that of previous methods, but this method requires fewer manipulations. One million lymphocytes are incubated for one hour with 2 micrograms of benzo(a)pyrene in a glass cuvette. The reaction is stopped by addition of neutral formalin and the cell suspension is alkalinized with NaOH. Fluorescence intensity of the suspension is measured with excitation at 465 nm and emission at 520 nm.  相似文献   

7.
Summary The effects of herbicides on chloroplast and bacterial photosynthetic reaction centers were assayed photoelectrochemically. A photoelectrochemical cell with a simple structure and a small sample volume was prepared. This method enabled the simple and effective detection of the inhibition. Photocurrent response reflected the mechanism of the inhibition by herbicides.  相似文献   

8.
Glyceraldehyde-3-phosphate dehydrogenase (GAPDs) was purified from human sperms and properties of the enzyme were investigated. After sonication of sperms, the most part of GAPDs is associated with the insoluble cell fraction. Trypsin treatment results in the cleavage of part of the N-terminal domain of the enzyme yielding a soluble fragment that was purified by hydrophobic chromatography on Phenyl-Sepharose. The isolated fragment was shown to be a tetramer with molecular weight of approximately 150 kD (according to Blue Native PAGE) and composed of subunits of 40 kD (according to SDS-PAGE). The specific activity of the isolated fragment reached 374 U/mg. It is supposed that GAPDs exists in sperms as the tetrameric molecule bound to the fibrous sheath of the flagellum through the N-terminus of one or two subunits. Comparative study of the amino acid sequences of mammalian GAPDs revealed conservative cysteine residues (C21, C94, and C150) that are specific for the sperm isoenzyme and absent in the somatic isoenzyme. Residue C21 can be involved in the formation of the disulfide bond between the N-terminal domain of GAPDs and fibrous sheath proteins.  相似文献   

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A new and simple colorimetric method for human serum lipase [EC 3.1.1.3] assay has been developed, using 2,3-dimercaptopropan-1-ol tributyroate as a substrate, 5,5'-dithiobis(2-nitro-benzoic acid) as a chromogenic reagent, phenylmethylsulfonyl fluoride as an inhibitor of serum esterases, and sodium dodecylsulfate as a lipase activator. The method requires only 50 micron1X2 of serum sample and a reaction time of less than 30 min. The method is reproducible and sensitive enough to measure low levels of lipase activity in normal and abnormal sera. The gel filtration of serum samples on a Sephadex G-200 column gave one peak of lipase activity, when measured by the present method, and the molecular weight of the enzyme was identical with that of lipase of human pancreatic origin, confirming the specificity of this new method for the serum lipase.  相似文献   

11.
SummaryObjectives: Defining the mechanism of infection with human herpesvirus-8 (HHV-8) or Kaposi’s sarcoma associated herpesvirus (KSHV) is an important clinical issue. HHV-8 has been linked to Kaposi’s sarcoma (KS) development in HIV-1-infected individuals, and KS develops in 40% of those infected with both viruses. A series of epidemiological data suggest that sexual transmission is one of the routes of transmission for HHV-8. In our studies, we sought to assess the cellular reservoirs of HHV-8 DNA in the semen of HIV-1-infected men and the potential role of HHV-8 infected spermatozoa in horizontal transmission.Design and methods: A nested polymerase chain reaction (PCR), in situ PCR (ISPCR) and a sodium iodide (NaI) DNA isolation technique that extracts both nuclear and episomal DNA were utilized to amplify specific genes in vitro and within intact cells to evaluate the types of seminal cells infected with HHV-8 in HIV-1-infected and uninfected men.Results HHV-8 was present in the spermatozoa and mononuclear cells of the semen in 64 of 73 (88%) HIV-1 infected individuals. Both the sperms as well as the mononuclear cells of the semen specimens of HIV-1 infected men were found to be infected with HHV-8. Multiplex ISPCR revealed that a significantly higher percentage of semen cells were infected with HHV-8 than HIV-1 (p>0.001). Rare (less than one in a 100,000) sperm cells were co-infected with both viruses. A co-culture of HHV-8 infected sperm with uninfected 293 or Sup-T1 cell lines resulted in an abortive infection of these cells with HHV-8. DNA isolation by NaI yielded 73% of the positive sperm, whereas the standard phenol/chloroform method resulted in significantly lower positives (45%) from the same specimens.Conclusions: Design and methods: Our data strongly suggest a potential sexual/horizontal route of transmission of HHV-8, via the HHV-8 infected sperm and other semen cells, where a large percentage of HIV-1 infected men’s sperm and other semen cells are infected with HHV-8. Co-culture studies have further supported the observations that HHV-8 in the sperm cells is infectious and capable of transmission of the virus to uninfected cells.  相似文献   

12.
Cryopreservation of sperms is common therapy but with multiple damages to sperms. The aim of this study was to assess the effect of insulin as a prosurvival factor on the most important functional parameters of human spermatozoa during cryopreservation. Semen samples were obtained from 15 normozoospermic men at age 25–40 years of old through masturbation. Cryopreservation of sperms was conducted along with adding 10, 100, 500 and 1000 (ng/ml) insulin and a control group was also considered by adding distilled water. Samples were cryopreserved for 2 weeks in liquid nitrogen. Then, after thawing sperm motility; cytosolic/mitochondrial reactive oxygen species (ROS) levels; and DNA fragmentation were analyzed. Data were analyzed by SPSS software using one-way ANOVA. Results showed that insulin at all doses significantly decreased cytosolic ROS especially in 10 ng/ml group (P˂0.05). Mitochondrial ROS also decreased by adding insulin in comparison to the control group, although unmeaningfully (P˃0.05). Insulin at 1000 (ng/ml) decreased DNA fragmentation, significantly (P˂0.05). Also, the number of motile sperms increased in all insulin groups but it wasn't meaningful (P˃0.05). Based on our findings adding insulin to semen leads to protecting effects against cryopreservation damages and increases sperms motility. Therefore, using insulin for human semen seems to could be suggested for future clinical applications.  相似文献   

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The viability of Mycobacterium tuberculosis (MTB) in serial sputum specimens from persistently smear positive patients was evaluated. The assay was based on oxidation-reduction of Alamar Blue and Malachite Green dyes that change their color in response to MTB growth. A total of 280 sputum specimens from 40 persistently smear positive TB patients and 40 sputa from non-tuberculosis patients were digested, decontaminated and examined microscopically. To check the MTB viability, the sediments from decontaminated samples were inoculated into three culture media: Lowenstein-Jensen (LJ) slants, Alamar Blue and Malachite Green culture tubes. We found that out of 280 smear positive specimens, the LJ culture was positive in 124 (44%). The numbers of correctly identified S+/C+ cases by Alamar Blue and Malachite Green were 118 (95%) and 116 (93%), respectively. The mean time required for reporting the positive signal in Alamar Blue culture tubes was 9 versus 11 days by Malachite Green culture tubes. In the standard LJ culture media the average detection time was 27 days (P < 0.05). The sensitivity of LJ was 99%, Alamar Blue 95% and Malachite Green 93%. The specificity was 100%, 92% and 93%, respectively. The oxidation-reduction method is rapid, sensitive and inexpensive in monitoring the treatment response of patients with pulmonary TB. Thus, using this method can be of paramount importance, particularly in resource-constrained areas.  相似文献   

15.
Østgaard  Kjetill 《Hydrobiologia》1993,255(1):513-520
The action of alginate lyases may be easily followed in a UV-spectrophotometer, since each cut of the alginate chain will create an unsaturated unit at the non-reducing end with a strong absorbance at 230 nm. During prolonged incubation, this absorbance will approach an apparent endpoint level that reflects the initial substrate concentration. On this basis, a standardized assay has been developed. A combination of purified mannuronate lyase from Haliotis tuberculata and purified guluronate lyase from Klebsiella pneumoniae is applied to get quantitative concentration estimates that do not depend on alginate composition. The production of alginate in Azotobacter vinelandii is included as an example of application. Most important, by applying both enzymes alone and in combination, the block composition of the alginate may be estimated. Data for a series of widely different alginates have been compared with those obtained by NMR.  相似文献   

16.
Toxoplasma gondii is the etiologic agent of toxoplasmosis. Although the combination of sulfadiazine and pyrimethamine is used as therapy for this disease, these drugs can have serious side effects and its use is limited in pregnancy. Therefore there is a need for new anti-T. gondii drugs in the clinic. Some systems for T. gondii drug screening have been described, but these have limitations and can be difficult. In order to solve these problems, we established a system to screen drugs in vitro that involved using cell viability methods to calculate drug selectivities, which are Trypan blue, [3-(4,5-dimethylthiazol-zyl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazoliuzolium, inner salt] (MTS) method and lactate dehydrogenase (LDH) assay. These assays were simple to establish and perform. The IC50 values calculated from the morphological assay were not significantly different from the EC50 values calculated using the other three methods. In particular, the results of the morphological assay showed a distinct association with the MTS assay (R = 0.9841). These assays could be used for a wide range of applications in the screening of new drugs and may provide an alternative to the techniques currently used to screen for candidate anti-T. gondii compounds in vitro. In this study, we also tested many compounds and identified some that had a good anti-T. gondii effect in vitro based on the MTS assay. This simple and fast system allowed us to determine which compounds to investigate further using in vivo experiments.  相似文献   

17.
J W Ferkany 《Life sciences》1987,41(7):881-884
Radioreceptor assays (RRAs) are analogous in concept to radioimmuno assays. Characteristic to both methods is the saturable, specific, competitive and reversible ligand/receptor interaction. The RRA is simple, sensitive and reproducible and provides a degree of precision comparable to more sophisticated analytical techniques. Since RRAs require little specialized equipment, they can be used routinely by any laboratory engaged in biochemical research or, as an inexpensive exercise to teach the fundamentals of ligand binding and analytical pharmacology.  相似文献   

18.
Phospholipase A2 (PLA2) activity is usually assayed with expensive radioactive or chromogenic substrates unsuitable for performing large numbers of assays. We have designed a simple microplate assay for human serum PLA2 using the chromogenic substrate 4-nitro-3-octanoyloxy-benzoic acid. Using this substrate, serum PLA2 activity was similar to that measured with the previously characterized chromogenic phospholipid substrate 1,2-bis-heptanoylthio-glycerophosphocholine. However, the assay described here appears to be more sensitive. The mean PLA2 activity in serum from healthy volunteers (n = 30) measured by this assay was 10.4 +/- 1.6 micromol x h(-1) x ml(-1). The assay is reproducible and is suitable for the analysis of large numbers of samples in a clinical setting. We have also demonstrated that 94% of the PLA2 activity in normal human serum is associated with high-density lipoproteins and that serum PLA2 activity is positively correlated with the lipoprotein parameters total triglyceride (P < 0.0001), total cholesterol (P < 0.0001), and atherogenic index (P = 0.008). The serum PLA2 activity was calcium dependent and was inhibited by the serine protease inhibitor 3,4-dichloroisocoumarin (EC(50) = 0.4 mM). The PLA2 activity characterized here is unlikely to be due to plasma platelet-activating factor acetylhydrolase or low molecular weight His-Asp sPLA2, and may represent a new sPLA2 type.  相似文献   

19.
A micronucleus test method to assess radiation-induced chromosomal damage in human spermatozoa is described, and its efficiency examined by comparison with that of sperm chromosome analysis. Human spermatozoa were exposed in vitro to 1.11 and 2.13 Gy of 137Cs gamma-rays at a dose rate of 1.36 Gy/min. After interspecific in vitro fertilization of irradiated spermatozoa with zona-free hamster oocytes, a total of 193 monospermic eggs were examined with the micronucleus test at the 2-cell stage, and a total of 304 male pronuclear chromosome plates were analyzed according to our established method. The incidence of 2-cell embryos with micronuclei coincided well with the incidence of spermatozoa with chromosomal breaks and fragments (51.6% vs. 50.3% in the 1.11-Gy group and 82.7% vs. 79.3% in the 2.13-Gy group). A similar correlation was also found between the number of micronuclei per embryo and the number of breaks and fragments per spermatozoon (0.85 vs. 0.88 and 1.50 vs. 1.45 in the 2 dose groups, respectively). These results indicate that our micronucleus test is useful as a simple and rapid method for assessing the clastogenic effects of various environmental mutagens on human sperm chromosomes.  相似文献   

20.
《Biochemical education》1999,27(3):171-173
A simple laboratory procedure is described for demonstrating the enzyme-catalysed reaction in the browning of potato. It requires a minimum of equipment and can be completed in a 3-h lab class.  相似文献   

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