Spermatozoa recovered by IxaPrep gradient have improved longevity and better motion characteristics than those by Percoll gradient

To compare the effectiveness of various sperm preparation methods, we examined sperm concentration, percentage of progressive motility, recovery rate, and various motion characteristics in 32 semen samples after Percoll and IxaPrep preparations. Except for sperm concentration, which was much higher after IxaPrep preparation, no statistical differences existed between these two methods in terms of motile sperm concentration (MSC), recovery rate, mean curvilinear velocity (VCL), mean straight-line velocity (VSL) and mean amplitude of lateral head displacement (ALH). Among 22 samples that were allocated in a 37 degrees C, 5% CO2 incubator, the mean MSC after 3 hours was significantly higher following IxaPrep preparation than following Percoll preparation (63.2 x 10(6)/mL vs. 42.8 x 10(6)/mL, p < .03). VCL and VSL were much higher after IxaPrep preparation than after Percoll preparation, both at 3 hours (p < .01) and at 24 hours (p < .03). ALH was also higher after IxaPrep preparation than after Percoll preparation, and it was statistically significant after 3 hours of incubation (p < .03). We conclude that the IxaPrep gradient may be adopted as the preferred method to the Percoll gradient in preparing spermatozoa for assisted reproduction because of the spermatozoa's persistent and better motion activities after incubation.

Ecological risk assessment using RAPD and distribution pattern of a rare and endangered species

Environmental and ecological risk assessment always provide useful evidence for characterisation and conservation of the rare and endangered species, e.g. seven-son flower (Heptacodium miconioides Rehd.). Seven-son flower is a deciduous arbor species, but endangered, with a restricted distribution in the subtropical forests of China. Genetic risk assessment of 56 samples of the flower from nine main populations in Zhejiang (China) was carried out by using the RAPD analysis. This was to study the ecological characteristics, spatial distribution and genetic features of the seven-son flower communities and establish a feasible conservation plan. Twenty-one primers screened from 50 yielded 119 RAPD bands with 72 polymorphic products and 60.50% of total bands. The genetic variation was found to be partitioned mainly among rather than within populations. Percentages of genetic diversity among populations were quantified by Shannon index and the Nei's gene diversity coefficient. AMOVA also demonstrated that these relict populations were highly differentiated. The high level of population variation observed is in contrast to that expected for a primarily outcrossed woody perennial plant, and suggests that there may be a degree of inbreeding. The dendrogram constructed from genetic distances through UPGMA method based on Nei's coefficients shows two groups among nine population clusters, which is further supported by a principle components analysis (PCA) of RAPD phenotypic data. The analysis showed that the biologic characteristics and habitat fragmentation were the reasons of the great genetic variation among populations. Some strategies of its genetic diversity conservation were proposed in the fragmented habitats based on its genetic structure and its biological characteristics in this study.

[The progress in management of esophagogastric variceal bleeding in cirrhotic portal hypertension]

Esophagogastric variceal bleeding (EVB) is the most dangerous complication of cirrhotic portal hypertension.With the continuous emergence of research findings on EVB, multiple disciplinary team, including internal medicine department, surgery department, intervention therapy department, radiology department, has become a new mode for the prevention and treatment of EVB. This article first reviewed the classification of esophageal varices and gastric varices, and then reviewed the recent research findings of EVB from three aspects: primary prophylaxis, active variceal bleeding treatment, and secondary prophylaxis.The aim was to provide new ideas for the individualized prevention and treatment of EVB.

Root growth inhibition and induction of DNA damage in soybean (Glycine max) by chlorobenzenes in contaminated soil

The cytotoxic and genotoxic effects of 1,2,4-trichlorobenzene (TCB), chlorobenzene (CB), and hexachlorobenzene (HCB) on root growth and DNA strand breakage damage of soybean nuclei in the test soil were studied using the comet assay. Results indicated that the root growth was significantly inhibited, and DNA strand breaks and the comet tail in the root tip nuclei were both induced after 48 h exposure with TCB concentrations of 50, 100, 200, 300 microg g(-1) in the soil. DNA strand breakage was more sensitive to the TCB than the root growth. There was a significant dose-response relationship between the TCB exposure and DNA strand breakage in the soybean nuclei. Thus it is possible for DNA strand breakage to be used as a biomarker of soybean exposed to TCB contamination. Significant cytotoxic threshold concentration of the TCB exposure on the root growth inhibition was determined as 61 microg g(-1) in the soil. The toxicity of 100-1,000 microg g(-1) CB and HCB to the soybean seedlings in the soil were not observed after 48 h or longer exposure.

Correlation between the immature characteristics of umbilical cord blood-derived mesenchymal stem cells and engraftment of hematopoietic stem cells in NOD/SCID mice

Umbilical cord blood (UCB)-derived mesenchymal stem cells (MSC) facilitate the engraftment of human (h) hematopoietic stem cells when transplanted simultaneously in animal and human studies. However, the type of MSCs that preferentially enhance the engraftment of HSCs is unknown. Recent studies have shown that MSCs derived from a single source are heterogeneous in terms of cell size, morphology, proliferation rate, and differentiation potential. This study was designed to investigate the properties of UCB-MSCs, which influence the engraftment of hHSCs in a NOD/SCID mouse model. We categorized MSCs as being the most effective (UCB-352 MSCs) or the least effective (UCB-156 MSCs) at promoting the homing and engraftment of HSCs, and compared the characteristics of these 2 MSC populations. We observed that the 2 populations showed differences in characteristics typical of immature MSCs, and related to proliferation potential. We showed that UCB-352 MSCs, which proliferate quickly, preferentially enhanced the engraftment of HSCs in NOD/SCID mice. In addition, we observed differences in the pattern of both PODXL and Oct4 expression, and in the levels of cytokines such as SDF-1 and SCF using flow cytometry and membrane arrays. The more effective UCB-352 MSCs expressed higher levels of PODXL and Oct4, which were associated with immaturity, than did the UCB-156 MSCs. Furthermore, UCB-352 cells secreted greater levels of SDF-1 and SCF, both of which are required for hematopoiesis. We propose that the proliferation potential of UCB-MSCs, coupled with their immature characteristics, may serve as a novel standard to promote the homing and engraftment of HSCs.

Revelation of intertwining organic and inorganic fractal structures in polymer coatings

X-ray microtomography and serial block face scanning electron microscopy are used to reveal independent clusters of inorganic particles embedded within a polymer. These clusters are interpenetrating, of varying size, and have fractal dimensions that strongly influence transport and structure-property relations. This interpretation forms a baseline for designing hybrid materials for applications in self-healing, drug delivery, and membranes.

Translaparoscopic tubal embryo transfer: preliminary experience at National Taiwan University Hospital

Forty-six couples with various causes of infertility were treated by tubal embryo transfer. Oocyte retrievals were carried out under ultrasound guidance transvaginally and embryos were transferred 48 hours later by laparoscopy into fallopian tubes. Totally 52 cycles were stimulated and 45 retrievals were performed with an average of 8.1 oocytes per retrieval. The average fertilization rate was 54.8%. The implantation rate was 23.8% and the pregnancy rate was 53.5% per transfer. The pregnancy rate per transfer was comparable whether 3 or 4 embryos were transferred. Nine (39.1%) of the 23 pregnancies had multiple pregnancies. Six cases (26.1%) aborted in the first trimester and the remaining 17 were ongoing or term delivery.

A simplified technique for embryo biopsy: use of the same micropipette for zona drilling and blastomere aspiration

PURPOSE

Using different micropipettes for zona drilling and blastomere aspiration for embryo biopsy is prevalent at centers of preimplantation genetic diagnosis. The purpose of our study was to simplify the technique by using only one micropipette.

METHODS

In this animal model, ICR mouse embryos at the four-cell stage (n = 446) were randomly allocated into two groups; a biopsied group (n = 224) for blastomere aspiration and a control group (n = 222) without micromanipulation. We used a drilling/biopsy micropipette to drill a hole in the zona by expulsion of acidified Tyrode's solution and to aspirate the blastomere by gentle suction with the same micropipette and pull it out of the zona. One blastomere was biopsied from each embryo.

RESULTS

In all, 222 (99.1%) intact blastomeres were successfully biopsied from 224 embryos. Only two blastomeres were damaged during aspiration. The capacity for blastocyst development (92.4 vs 93.7%) was not different between the two groups, but the percentages of embryos hatching (51.8 vs 18.0%) and hatched (29.9 vs 8.1%) were significantly higher in the biopsied group than in the control group.

CONCLUSIONS

This simplified technique of embryo biopsy is safe and highly efficient for obtaining blastomeres for preimplantation genetic diagnosis and may also facilitate hatching of the blastocysts.

Recovery of motile sperm using the osmolality-gradient technique

A simple, effective method for collecting motile sperm from ejaculates is developed. One hundred semen samples were obtained from both fertile and infertile men. Following initial semen dilution (1: 1) to 4 mL in a hypoosmotic medium (210 mOsm/kg), the mixture was layered into the specially designed tube filled with 1 mL recovery medium in the bottom and 1 mL isolation medium in the second layer to form three discrete layers. During the next hour the highly motile sperm out-distanced the other seminal contents to reach the bottom of the tube. Compared with the parent ejaculates, the recovered specimens exhibited an increased percentage of motile sperm with significantly enhanced sperm velocity and linearity (p less than .001). This method isolated motile sperm with higher velocity than those obtained using the swim-up technique.

Secretion of human chorionic gonadotropin and alpha-fetoprotein by an ovarian germ cell tumor of apparent yolk sac origin

alpha-Fetoprotein (alpha FP) and four placental proteins, human chorionic gonadotropin (hCG), human placental lactogen (hpL), pregnancy specific beta 1-glycoprotein (SP1), and placental protein 5 (PP5), were measured in a 17-year-old patient with endodermal sinus tumor of the ovary. The circulating levels of alpha FP were consistently high (more than 14 mg/ml), and alpha FP was localized in tissue sections using immunohistochemical techniques. None of the four placental proteins was detectable in serum samples, but hCG was detected in urinary concentrates in an episodic manner. This ectopic hCG resembled placental hCG in its physicochemical and immunological characteristics. Unlike alpha FP, hCG was not detected in the tumor by immunohistochemical methods. This study indicates that the neoplasm elaborated both hCG and alpha FP. Whether pure endodermal sinus tumor of the ovary is capable of secreting hCG cannot be answered by this study because of limited histologic sampling. The likelihood that this represents a mixed germ cell tumor in which only the endodermal sinus tumor element was sampled remains a possibility. This study also indicates that the 24-hr urinary concentrate is far more sensitive than serum samples for hCG detection.

Determination of tolerance to tear protein release following a twice a day topical application of N,N-dimethyl-2-phenylethylamine HCl

In an effort to develop a long-term topically active tear stimulant, it was important to determine if tolerance developed following the repeated instillation of N,N-Dimethyl-2-phenylethylamine hydrochloride (AF2975) to the albino rabbit eye. New Zealand white rabbits were administered AF2975 (0.15%) twice a day (9 am and 4:30 pm) for 10 days. The right eye received the drug solution (50 microliters) and the left eye received an equal volume of the vehicle. Prior to dosing and at the end of first and last dose (10 and 60 minutes post-dosing), protein secretion was measured with the use of Schirmer tear test strips placed under the lower lid of each eye for five minutes. The strips absorbed tears from which protein was extracted. Eyes treated with AF2975 showed a statistically significant % increase in protein release compared to baseline values. Control eyes did not show statistically significant increases over baseline. A comparison of % changes from baseline in protein secretion rates after the first and last dose showed no significant differences in either treated or control eyes at 10 and 60 minutes postdosing. These results indicate that tolerance does not occur for protein secretion of topically administered AF2975 (0.15%) following a twice a day dosing schedule for 10 days to the rabbit eye.

Histone gene switching in murine erythroleukemia cells is differentiation specific and occurs without loss of cell cycle regulation

We investigated the expression characteristics of the fully replication-dependent (FRD) and the partially replication-dependent (PRD) histone gene variants by measuring changes in steady-state mRNA levels during hexamethylene bisacetamide (HMBA)-induced differentiation of murine erythroleukemia (MEL) cells. Between 24 and 60 h after induction, there was a dramatic switch in histone gene expression, such that the ratio of PRD to FRD transcripts increased severalfold over that found in uninduced MEL cells. We demonstrated that this gene switching was not simply a partial or complete uncoupling of PRD gene expression from DNA synthesis. PRD and FRD transcript levels were regulated coordinately upon treatment of uninduced or induced MEL cells with inhibitors of DNA synthesis, protein synthesis, or both. Using several criteria, we were unable to detect any difference in PRD and FRD gene expression under any conditions except in cells undergoing differentiation. MEL cells were arrested at a precommitment stage of differentiation by induction with HMBA in the presence of dexamethasone (DEX). If DEX was subsequently removed, DNA synthesis resumed, the cells underwent commitment, and histone gene switching was observed. In contrast, if both DEX and HMBA were removed, DNA synthesis still resumed, but commitment did not occur and no gene switching was observed. These results imply that histone gene switching is intimately related to the differentiation process.

Wide-angle fluorescein angiographic scanning with high resolution using a scanning laser ophthalmoscope through a mirror image fixation target

Internal and moving targets of scanning laser ophthalmoscopes are not capable of observing the fundus beyond a field of more than 80 degrees with high resolution. The authors enabled wide-angle fundus examination with high resolution through a modification of the target. Mirror image fixation targets(MIFT), which fixated the opposite side of the examined eye onto the mirror image of five lamps placed 1.5 m away from the patient, were used to observe the fundus during fluorescein angiography in five diabetic retinopathy patients. In three of them, the ranges of the fundus examinations were measured using conventional internal fixation targets. The mean ranges of the fundus examinations when using MIFT (77.2 +/- 2.5 degrees horizontally, 67.9 +/- 2.1 degrees vertically) were significantly wider than when using internal fixation targets (65.5 +/- 2.6 degrees horizontally, 44.4 +/- 2.8 degrees vertically). MIFT provided a wide angle fundus view with high resolution equal to that of 40 degrees angle images using a scanning laser ophthalmoscope.

Hydrogeo-chemical impacts of air sparging remediation on a semi-confined aquifer: evidences from field monitoring and modeling

Air sparging (AS) was explored for remediation of a petroleum contaminated semi-confined groundwater system in NE China. Physical, hydro-chemical and hydraulic behaviors in subsurface environment during AS were investigated with support of modeling to understand the hydrogeo-chemical impacts of AS on the aquifer. The responses of groundwater, dissolved oxygen and temperature indicated that the radius of influence of AS was up to 8-9 m, and a 3D boundary of the zone of influence (ZOI) was accordingly obtained with volume of 362 m(3). Water mounding unlike normal observations was featured by continuous up-lift and blocked dissipation. AS induced water displacement was calculated showing no obvious spreading of contaminant plume under this AS condition. Slug tests were employed before and after AS to reveal that the physical perturbation led to sharp increase in permeability and porosity. Modeling indicated that the regional groundwater flow field was not affected by AS except the physical perturbation in ZOI. Hydro-chemically increase of pH and Eh, and reduction of TDS, electrical conductivity and bicarbonate were observed in ZOI during AS. PHREEQC modeling inferred that these chemical phenomena were induced by the inorganic carbon transfer during air mixing.

Microinjection of human sperm into perivitelline space of hamster eggs: comparison with zona-free hamster egg penetration of human sperm

Micromanipulation of human sperm and oocyte has been utilized to facilitate fertilization of those patients with male factor due to oligoasthenospermia or those patients with repeated fertilization failure in an in vitro fertilization (IVF) program. Before manipulating human gametes, one needs experience with animal models. Our objective was to perform subzonal insertion of human sperm into hamster eggs and to compare the result with that of sperm penetration assay (SPA) using zona-free hamster eggs. Semen samples were obtained from 15 fertile donors with normal semen analysis and the motile sperm were collected by swim-up procedure. Microinjection was performed by injecting a varied number of sperm into the perivitelline space of 222 hamster eggs pretreated with sucrose solution (0.1 M). The rate of damage of eggs during microinjection was 7.2% (16/222). The rates of penetration in the microinjection group were 5.1% (4/79) for 1-5 sperm injected, 10.9% (11/101) for 6-10 sperm injected, and 11.5% (3/26) for 11-15 sperm injected. The average rate of penetration per egg was 8.7% (18/206), and the polyspermic rate was 11.1% (2/18). Simultaneously SPA was performed in each sample of semen as a positive control, and the average rate of penetration of SPA was 51.4% (108/210). The rate of penetration in the microinjection group was significantly smaller (p < .05) than that in the SPA group. Whether the penetration rate and polyspermic rate in a hamster model reflect similar results in human oocyte requires further investigation. However, the hamster egg provides an ideal model to develop a micromanipulation technique for human beings.

Nonserine esterases from rat liver cytosol

An effort to identify the major general esterases of rat liver cytosol that are insensitive to the serine esterase inhibitor paraoxon (diethyl 4-nitrophenyl phosphate) has led to the isolation of a dozen enzymes. Four of these are electrophoretically homogeneous. Although purified on the basis of their hydrolytic activity toward 4-nitrophenyl acetate, each of the enzymes has a very broad and overlapping substrate specificity for aromatic esters. Thiol esters serve as substrates but, within the limits of the methods used, amides are not hydrolyzed.

Mouse embryo toxicity of IL-6 in peritoneal fluids from women with or without endometriosis

BACKGROUND

To determine whether there is a factor (or factors) in the peritoneal fluid of endometriosis patients that impairs embryo growth and embryo implantation.

METHODS

Growth and development of two-cell mouse embryos which were cultured in media with peritoneal fluid from women with or without endometriosis and interleukin-1-beta (IL-1beta), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) levels in conditioned media were measured.

RESULTS

The blastocyst rate in the non-endometriosis group was 46.4 +/- 31.1%, and that of the endometriosis group was 54.6 +/- 28.7%. Logistic regression analysis using the criteria of blastocyst development in 454 embryos, showed that the peritoneal fluid from endometriosis could promote (p=0.015) but IL-6 could arrest embryo growth to blastocyst (p=0.025). IL-1beta and TNF-alpha levels had no significant effect on blastocyst formation.

CONCLUSION

Peritoneal fluid from women with endometriosis was not toxic to mouse embryo development. However, IL-6 in the peritoneal fluid deteriorated the growth and development of mouse embryos.