Visual Immunoprecipitate Assay (VIP) for Listeria monocytogenes and Related Listeria Species Detection in Selected Foods: Collaborative Study

Six foods representing a variety of food products were analyzed by the Assurance Listeria polyclonal enzyme immunoassay (EIA) and by either the Bacteriological Analytical Manual or the U.S. Department of Agriculture culture method for detecting Listeria monocytogenes and related Listeria species. Samples of each food type, at each inoculation level, were analyzed simultaneously by both methods. A total of 19 laboratories representing federal government agencies and private industry in the United States and Canada participated. Food types were inoculated with Listeria species including L. monocytogenes, with the exception of 3 lots of green beans, which were naturally contaminated. During this study, 1764 samples and controls were analyzed and confirmed, of which 492 were positive and 947 were negative by both methods. There were 159 samples that were positive by culture method but negative by the EIA and 188 that were negative by culture method but positive by EIA. Twenty-two samples were negative by EIA and by culture method but confirmed positive when Assurance selective enrichment broths were subcultured to selective agar. The Assurance polyclonal EIA for detecting L. monocytogenes and related Listeria species in foods has been adopted first action by AOAC INTERNATIONAL.

Assurance Enzyme Immunoassay for Detection of Enterohemorrhagic Escherichia coli 0157:H7 in Selected Foods: Collaborative Study

Five foods types were analyzed by the Assurance EHEC (Escherichia coli 0157:H7) enzyme immunoassay (EIA) and by the Bacteriological Analytical Manual (BAM) culture method. Each sample of each food type at each inoculation level was simultaneously analyzed by both methods. A total of 21 laboratories representing state and federal government agencies and private industry in the United States and Canada participated. Samples were inoculated with E. coli 0157:H7, except for one lot of poultry that was naturally contaminated. A total of 1304 samples and controls were analyzed and confirmed, of which 473 were positive and 818 were negative by both methods. Thirteen samples were positive by BAM but negative by EIA. Because of the study design, it was not possible for the BAM method to produce false-negative or falsepositive results. The Assurance method for detection of E. coli OI57:H7 in selected foods has been adopted first action by AOAC INTERNATIONAL.

Visual Immunoprecipitate Assay (VIP) for Detection of Enterohemorrhagic Escherichia coli (EHEC) 0157:H7 in Selected Foods: Collaborative Study

Five foods representative of a variety of food products were analyzed by the Visual Immunoprecipitate Assay (VIP) and the Bacteriological Analytical Manual (BAM) culture method for the presence of Escherichia coli 0157: H7. A total of 21 laboratories representing state and federal government agencies, as well as private industry, in the United States and Canada participated. Food types were inoculated with strains of E. coli 0157:H7, with the exception of one lot of poultry, which was naturally contaminated. During this study, a total of 1377 samples and controls were analyzed and confirmed, of which 508 were positive and 867 were negative by both methods. Two samples were positive by BAM and negative by VIP. Because of the study design, it was not possible for the BAM method to produce false-negative or false-positive results. The VIP assay for detection of EHEC in selected foods has been adopted first action by AOAC INTERNATIONAL.

Assurance Polyclonal Enzyme Immunoassay for Detection of Listeria monocytogenes and Related Listeria Species in Selected Foods: Collaborative Study

Six foods representing a variety of food products were analyzed by the Assurance Listeria polyclonal enzyme immunoassay (EIA) and by either the Bacteriological Analytical Manual or the U.S. Department of Agriculture culture method for detecting Listeria monocytogenes and related Listeria species. Samples of each food type, at each inoculation level, were analyzed simultaneously by both methods. A total of 19 laboratories representing federal government agencies and private industry in the United States and Canada participated. Food types were inoculated with Listeria species including L. monocytogenes, with the exception of 3 lots of green beans, which were naturally contaminated. During this study, 1764 samples and controls were analyzed and confirmed, of which 492 were positive and 947 were negative by both methods. There were 159 samples that were positive by culture method but negative by the EIA and 188 that were negative by culture method but positive by EIA. Twenty-two samples were negative by EIA and by culture method but confirmed positive when Assurance selective enrichment broths were subcultured to selective agar. The Assurance polyclonal EIA for detecting L. monocytogenes and related Listeria species in foods has been adopted first action by AOAC INTERNATIONAL.

Determination of Vitamins A (Retinol) and E (alpha-Tocopherol) in Foods by Liquid Chromatography: Collaborative Study

A collaborative study was conducted for the determination of vitamins A and E. Existing AOAC liquid chromatographic (LC) methods are suited for specific vitamins A and E analytical applications. This method differs from existing methods in that it can be used to assay samples in all 9 sectors of the food matrix. Standards and test samples are saponified in basic ethanol–water solution, neutralized, and diluted, converting fats to fatty acids and retinol esters and tocopherol esters to retinol and tocopherol, respectively. Retinol and alpha-tocopherol are quantitated on separate LC systems, using UV detection at 313 or 328 nm for retinol, and fluorescence detection (excitation 290 nm, emission 330 nm) for alpha-tocopherol. Vitamin concentrations are calculated by comparison of the peak heights or peak areas of vitamins in test samples with those of standards.

Equivalence of Assurance® Gold Enzyme Immunoassay for Visual or Instrumental Detection of Motile and Nonmotile Salmonella in All Foods to AOAC Culture Method: Collaborative Study

Six foods representative of a wide variety of processed, dried powder processed, and raw food types were analyzed by the Assurance® Gold Salmonella Enzyme Immunoassay (EIA) and AOAC INTERNATIONAL culture method. Paired samples of each food type were simultaneously analyzed; one sample by the Assurance method and one by the AOAC culture method. The results for Assurance method were read visually and instrumentally with a microplate reader. A total of 24 laboratories representing federal government agencies and private industry, in the United States and Canada, participated in this collaborative study. Food types were inoculated with species of Salmonella with the exception of raw ground chicken, which was naturally contaminated. No statistical differences (p < 0.05) were observed between Assurance Gold Salmonella EIA with either visual or instrumental interpretation and the AOAC culture method for any inoculation level of any food type or naturally contaminated food. The Assurance visual and instrumental options of reading sample reactions produced the same results for 1277 of the 1296 sample and controls analyzed.

FOXO1 targeting by capsaicin reduces tissue damage after testicular torsion

Testicular torsion-related oxidative stress causes a sequential chain of DNA damage, lipid peroxidation and cell death that leads to the derangement in the sperm functions and infertility. Capsaicin that has been applied for pain relief and cancer prevention possesses antioxidant properties which can be exploited to confer cell survival under ischaemic testis damage. Wistar male rats weighing 150-200 g were randomly divided into four groups: (i) sham group (all procedures except torsion of testis), (ii) ischaemia group (TT group), (iii) three TT groups treated with different dose of capsaicin (TT + different doses of Cap) and (iv) three control groups treated with different doses of capsaicin (100, 500 and 1000 ug/ml). Capsaicin administration significantly decreased the expression of pro-apoptotic factors and increased the expression of anti-apoptotic factors. Likewise, the expression of FOXO1 is significantly increased by higher doses of the capsaicin. Histological assessment by H&E and TUNEL method also exhibited an improved testicular morphology and decreased apoptosis in testes. These results suggested clinical potential for capsaicin in treatment of testicular torsion by targeting FOXO1 and apoptotic pathways.

Increased sperm ubiquitination correlates with abnormal chromatin integrity

Ubiquitin, a 8.5 kDa peptide that marks other proteins for proteasomal degradation, tags defective spermatozoa during epididymal passage and is proposed as a biomarker for sperm quality. The present study was designed to evaluate the relationships between sperm ubiquitination, sperm chromatin integrity and semen parameters. Semen samples from 63 couples were collected and analysed according to World Health Organization criteria. Each sample was evaluated for sperm ubiquitination by the direct immunofluorescence method, using anti-ubiquitin antibodies. Chromatin integrity of the same samples was analysed using acridine orange (AO) and toluidine blue (TB) tests. A positive correlation was found between ubiquitinated spermatozoa and the percentage of spermatozoa with abnormal chromatin (AO: r = 0.58, P < 0.001 and TB: r = 0.48, P < 0.001). Negative correlations were obtained between sperm ubiquitination and: sperm count (r = -0.2, P = 0.048), sperm morphology (r = -0.36, P = 0.003), rapidly progressive motility (r = -0.25, P = 0.044) and slow progressive motility (r = -0.28, P = 0.022). Sperm ubiquitination was positively correlated with the percentage of immotile spermatozoa. These results show that among semen parameters, chromatin abnormality is more closely associated with sperm ubiquitination and further validate sperm ubiquitination as a suitable marker for sperm quality.

DNA damage of human spermatozoa in assisted reproduction: origins, diagnosis, impacts and safety

Sperm DNA contributes half the offspring's genomic material and abnormal DNA can lead to derangements in the reproductive process. Normal sperm genetic material is required for successful fertilization, as well as for further embryo and fetal development that will result in a healthy child. Thus, the damage to sperm DNA is critical in assisted reproductive techniques which are increasingly used to treat infertile couples. There has been improving data about the effects of human sperm DNA damage or fragmentation. As well, increasing knowledge concerning the effects of DNA damage on embryo and fetal development has been attained. This review aims to summarize the present knowledge on the impact of human sperm cell DNA damage on male infertility and outcome in the context of safety.

Hydrosalpinx and IVF: assessment of treatments implemented prior to IVF

It is well known that the success of artificial reproductive techniques, especially IVF, for patients with tubal pathologies such as hydrosalpinx is reduced by half compared with patients without hydrosalpinx. Notably, there are also substantial increases in both early pregnancy loss and ectopic pregnancies. Alterations in the outcome of these patients generally reflect a detrimental effect of hydrosalpinx. However, although many theories have been published, a single explanation has not yet been found over a period of decades. Therefore, the negative effects of hydrosalpinx have generally been attributed largely to: (i) mechanical effects; (ii) embryo and gametotoxicity; (iii) alterations in endometrial receptivity markers; or dwindled cross talk between embryo-endometrium resulting in hindered implantation, and (iv) direct effect on endometrium, leading to intrauterine fluid formation. On the other hand, the most important question is selection of the preferred treatment option with either surgical or medical therapies. How should hydrosalpinx be managed? Does selection of the surgical method, either proximal obstruction or salpingectomy, depending on patients' clinical findings, differ in outcome, or is routine prophylactic salpingectomy needed? Additionally, the requirement for IVF or intracytoplasmic sperm injection is still controversial in patients with unilateral hydrosalpinx who have been treated with unilateral salpingectomy.

Elective cryopreservation of all pronuclear oocytes after GnRH agonist triggering of final oocyte maturation in patients at risk of developing OHSS: a prospective, observational proof-of-concept study

BACKGROUND

A bolus dose of GnRH agonist can substitute for hCG as a trigger for the resumption of meiosis in ovarian stimulation with GnRH antagonists, which has been suggested to reduce the risk of ovarian hyperstimulation syndrome (OHSS). As the efficacy of this measure in fresh embryo transfer (ET) cycles is unclear, we evaluated a new clinical concept of GnRH-agonist triggering.

METHODS

In this prospective, observational proof-of-concept study, 20 patients considered at increased risk of developing OHSS (> or = 20 follicles > or = 10 mm or estradiol > or = 4000 pg/ml, or a history of cycle cancellation due to OHSS risk or the development of severe OHSS in a previous cycle) after ovarian stimulation and concomitant GnRH-antagonist administration had final oocyte maturation triggered with 0.2 mg triptorelin s.c. All two pronucleate (2 PN) oocytes were cryopreserved by vitrification, and frozen-thawed ETs (FT-ETs) were performed in an artificial cycle. Main outcome measures were the cumulative ongoing pregnancy rate per patient and the ongoing pregnancy rate per first ET. Secondary outcomes included the incidence of moderate-to-severe OHSS.

RESULTS

Of the 20 patients triggered with GnRH agonist, 19 patients underwent 24 FT-ETs in the observational period. The cumulative ongoing pregnancy rate was 36.8% (95% confidence interval: 19.1-59.0%). The ongoing pregnancy rate per first FT-ET was 31.6% (15.4-54.0%). No cases of moderate or severe OHSS were observed.

CONCLUSIONS

The present study is the proof of the concept that GnRH-agonist triggering of final oocyte maturation in combination with elective cryopreservation of 2 PN oocytes offers OHSS risk patients a good chance of pregnancy achievement, while reducing the risk of moderate and severe OHSS.

Cytokine profile in cases with premature elevation of progesterone serum concentrations during ovarian stimulation

The aim of this study was to investigate the concentrations of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), leptin, tumor necrosis factor-alpha, interleukin (IL)-1beta and IL-6, in cycles with a premature rise of serum progesterone. 25 intracytoplasmic sperm injection (ICSI) cycles with (Group 1) and 25 ICSI cycles without a premature progesterone elevation (Group 2) were included. The cut-off value of serum progesterone on the day of human chorionic gonadotropin (hCG) administration was 0.9 ng/ml. The indication for ICSI was male factor infertility exclusively. On the day of hCG injection, serum IL-6, VEGF and bFGF were significantly higher in Group 1 (7.7+/-24.5 pg/ml, 290.2+/-161.4 pg/ml and 15.7+/-8.2 ng/ml respectively) than in Group 2 (1.7+/-0.7 pg/ml, 175.2+/-92.1 pg/ml, and 9+/-1.6 ng/ml respectively). On the day of follicular puncture, serum cytokine concentrations were similar in the two groups. IL-6 intrafollicular concentrations were higher in Group 1 (14.7+/-20.7 pg/ml) than in Group 2 (9+/-9.3 pg/ml, p=0.031). There were no differences regarding the ICSI outcome. Patients with serum progesterone above 0.9 ng/ml, have elevated serum concentrations of IL-6, VEGF, and bFGF, as well as elevated intrafollicular concentrations of IL-6. The outcome of ICSI cycles is not associated with premature elevation of progesterone when the cut-off value is set at 0.9 ng/ml.

Comparison of reactive oxygen species concentration in seminal plasma and semen parameters in partners of pregnant and non-pregnant patients after IVF/ICSI

The aims of this study were (i) to determine and compare the concentration of reactive oxygen species (ROS) and total antioxidant status (TAS) in seminal plasma and sperm parameters of the male partners of patients undergoing IVF or intracytoplasmic sperm injection (ICSI) treatment and (ii) to establish the relationship between ROS and TAS concentrations and sperm quality and their effect on fertilization and pregnancy rate of patients who achieved a pregnancy and those who were unsuccessful. Twenty-six IVF and 22 ICSI patients were included in this study. The ROS concentration in seminal plasma and sperm concentration, vitality (eosin test), motility, morphology, membrane integrity (HOS test), maturity (chromomycin, CMA3) and DNA fragmentation (TUNEL) results and their relationship to fertilization and pregnancy were analysed. ROS concentrations were similar regarding the seminal plasma of male partners of patients who achieved a pregnancy and those who were unsuccessful. The other semen parameters, concentration, motility, vitality, membrane and DNA integrity, were comparable in both groups. However, both groups demonstrated a negative correlation between ROS concentration and sperm vitality, membrane integrity and morphology. Moreover, an inverse correlation was found between TUNEL, vitality, and membrane integrity. In conclusion, ROS concentration in seminal plasma affects the quality of spermatozoa. A negative correlation between the ROS concentration in seminal plasma and fertilization rate in both IVF/ICSI programmes was shown.