International collaborative follow - up investigation of graduating high school students’ understandings of the nature of scientific inquiry: is progress Being made?

Understandings of the nature of scientific inquiry (NOSI), as opposed to engaging students in inquiry learning experiences, are included in science education reform documents around the world. However, little is known about what students have learned about NOSI during their pre-college school years. The purpose of this large-scale follow-up international project (i.e. 32 countries and regions, spanning six continents and including 3917 students for the high school sample) was to collect data on what exiting high school students have learned about NOSI. Additionally, the study investigated changes in 12th grade students’ NOSI understandings compared to seventh grade (i.e. 20 countries and regions) students’ understandings from a prior investigation [Lederman et al. (2019). An international collaborative investigation of beginning seventh grade students’ understandings of scientific inquiry: Establishing a baseline. Journal of Research in Science Teaching, 56(4), 486–515. https://doi.org/10.1002/tea.21512]. This study documents and discusses graduating high school students’ understandings and compares their understandings to seventh grade students’ understandings of the same aspects of scientific inquiry for each country. It is important to note that collecting data from each of the 130+ countries globally was not feasible. Similarly, it was not possible to collect data from every region of each country. A concerted effort was made, however, to provide a relatively representative picture of each country and the world

Comparative study of follicular fluid and cultured granulosa cell steroid production

To determine the steroidogenic capacity of follicular and cultured granulosa cells, estradiol and progesterone productions were studied in 10 fertilized and 10 nonfertilized IVF-ET cases. After separation of granulosa cells, they were cultured in EBSS within 24 hours. Follicular fluid obtained from follicles with fertilized oocytes contained higher levels of estradiol (E2), progesterone (P) and P/E2 ratio although the differences were statistically nonsignificant. Cultured granulosa cells demonstrated higher numbers per mililiter in fertilized oocyte group in comparison with the nonfertilized ones (p<0.05). However, nonfertilized group showed higher estradiol and progesterone production per 10 million granulosa cells (p<0.05) while P/E2 production rate of cultured granulosa cells was higher than the P/E2 ratio of fertilized group (p<0.05). These results suggest that preovulatory granulosa cell steroid production in favor of progesterone may deteriorate fertilization

Sperm acrosin activity and fertilization success

Purpose of this study was to determine the impact of acrosine activity of ejaculated human spermatozoa on in vitro fertilization success [1]. 71 samples picked up from routine screening for infertility and for IVF-ET procedures were divided into four groups and total acrosin activity of semen samples were estimated biochemically by a method of acrosin assay [2]. Total acrosin levels were lower in subjects with oligospermia and teratospermia. The strongest positive correlation was determined between acrosin activity and fertilization rate amongst the all parameters. In conclusion, measurement of acrosin activity may be a valuable laboratory tool for assessing the sperm fertilization potential for normo and oligospermic subjects

Evaluation of the fetal kidney maturation by assessment of amniotic fluid alpha-1 microglobulin levels

Objective: To evaluate the fetal renal maturation by assessment of amniotic fluid microproteins and to show these proteins originate from fetal urine. Study design: Amniotic fluid proteins (total protein, albumin, high molecular weight protein-HMWP, low molecular weight protein-LMWP, alpha(1)-microglobulin and beta(2)-microglobulin) were determined in 39 pregnant women at delivery and by amniocentesis in 30 pregnant women. These values were compared with first urine values of neonates with the same gestational age. Results: Albumin was the largest protein component in the amniotic fluid. LMWP showed an increase in the amniotic fluid until the end of the second trimester; and as pregnancy advanced a progressive decrease occurred in parallel to fetal renal maturation. After 26 weeks' gestation, a strong correlation was identified between LMWP levels and alpha(1)-microglobulin, and between LMWP and beta(2)-microglobulin. No significant difference was detected between LMWP levels in the first urine of the neonates and in amniotic fluids. Conclusion: Microproteins in the fetal urine are of fetal origin. Fetal renal maturation can be evaluated by measuring microproteins in the amniotic fluid. Fetal renal maturation is best reflected by alpha(1)-microglobulin. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved

Does leukocytospermia associate with poor semen parameters and sperm functions in male infertility? The role of different seminal leukocyte concentrations

To investigate the effect of leukocytospermia on standard semen analysis and sperm function tests such as acrosome reaction, hypoosmotic swelling, antisperm antibody binding and cervical mucus penetration, a prospective clinical study was performed. Two hundred and nineteen male infertility patients undergoing investigation and treatment were included in the study. There was a significant association between acrosome reaction positivity and leukocytospermia according to WHO (World Health Organization) criteria. Increased hypoosmotic swelling test score, higher sperm concentration and enhanced acrosome reaction were closely related to leukocytospermia. When the patients were divided into subgroups according to seminal leukocyte concentrations, acrosome reaction and hypoosmotic swelling were observed to be higher in semen samples with higher leukocyte concentrations compared to those with low seminal leukocyte concentration. In addition, higher sperm concentrations were observed in semen samples with increased leukocyte levels compared to semen samples with low leukocyte levels. These results suggest that leukocytospermia may have a favorable effect on some sperm functions at seminal leukocyte concentrations between 1 and 3 x 10(6)/ml. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved

Antibiotic therapy in men with leukocytospermia

Objective-In this prospective study, we aimed to determine the efficacy of doxycycline and doxycycline plus ceftriaxone for the treatment of asymptomatic men with leukocytospermia. Method-Seventy men were included in this randomized and placebo-controlled study. White blood cell (WBC) concentrations were determined by peroxidase assay during the routine semen analysis. Twenty-four of 70 men with leukocytospermia were randomized as control group and administered placebo (group I), 25 received doxycycline alone (group II), and 21, doxycycline plus ceftriaxone (group III). Doxycycline, 100 mg, was given twice a day for ten days and ceftriaxone, 1 g, in two doses for only one day. After the treatment, semen analyses were repeated. Results-After the treatment there was a significant decrease in WBC counts in groups II and II when compared with group I (P < .05). Both antibiotic regimens were found to be equally effective. However, the time needed for resolution of leukocytospermia (similar to 4 weeks) was similar between the control and treatment groups. Conclusion-Although both antibiotic regimens significantly, and equally improved the white blood cell counts in men with leukocytospermia, they failed to treat the leukocytospermia, i.e., to bring the count below the limit of one million WBC/mL. Therefore, it is doubtful that antibiotic therapy should be recommended for asymptomatic men with leukocytospermia