Analysis of Human Sperm Chromatin Integrity

Determining potential maternal or paternal sources of abnormal chromosomal constitution gives opportunity for preconception genetic counseling. The most direct determination is achieved by analyzing the nuclear constitution of the gametes. The present study evaluated the integrity of human spermatozoal nuclear material in the two condensation stages of chromatin and chromosomes. Original semen samples (ORI) and their swim-up fractions (SW, selected for motility) from men of known (donors) and unknown (patients) fertility were analyzed. The extent of chromatin condensation was assessed by light microscopy and flow cytometry during the time course of a chemically-induced decondensation reaction. Motile spermatozoa were used to inseminate hamster oocytes for human sperm chromosomal analysis (original method). A modification of this technique was introduced in an attempt to overcome the motility barrier required for fertilization. Spermatozoa rendered immotile by cryodamage were directly microinjected into the perivitelline space of hamster oocytes in order to obtain fertilization and possible chromosomal development. The swim-up-selected spermatozoa showed a higher resistance to the chromatin decondensation assay (10.53% decondensed) than their corresponding nonselected whole semen samples (94.74%). Sperm chromosomal analysis by the traditional technique was restricted to donor samples (86.7% fertilization rate) since all the patients failed to achieve fertilization. Although a high number of chromosomal complements were obtained (2362) only 7.4% provided complete information (range 0-56 complements/donor). The observed X/Y relationship (39/44) was not significantly different than the expected 1/1 ratio. Ten spermatozoa (7.69%) carried structural and 3.08% carried numerical abnormalities. High rates of fertilization (64-86%) with low rates of polyspermy ($ Swim-up selected spermatozoa have a higher resistance to the in-vitro induced nuclear chromatin decondensation assay (NCDA) than their corresponding ORI samples, which may correlate with their greater nuclear stability. Although SW procedures are invaluable as an aid in infertility treatment due to their selectivity in motility, morphology, fertilizing ability, chromatin resistance, etc. they are not able to discriminate against spermatozoal carriers of genetic defects

Influence of Exposure to Benzo[a]pyrene on Mice Testicular Germ Cells during Spermatogenesis

The objective of this study was to assess the toxicological effect of exposure to benzo(a)pyrene, B[a]P, on germ cells during spermatogenesis. Mice were exposed to B[a]P at 1, 10, 50, and 100 mg/kg/day for 30 days via oral ingestion. Germ cells, including spermatogonia, spermatocytes, pachytene spermatocytes, and round spermatids, were recovered from testes of mice exposed to B[a]P, while mature spermatozoa were isolated from vas deferens. Reproductive organs were collected and weighed. Apoptotic response of germ cells and mature spermatozoa were qualified using the terminal deoxynucleotidyl transferase mediated deoxy-UTP nick end labeling (TUNEL) assay. B[a]P exposure a

Legacy of wood charcoal production on subalpine forest structure and species composition

Land-use legacy on forest dynamics at both stand and landscape scale can last for centuries, affecting forest structure and species composition. We aimed to disentangle the history of the charcoal production legacies that historically shaped Mont Avic Natural Park (Aosta Valley, Italy) forests by integrating LiDAR, GIS, anthracological, and field data at the landscape scale. We adopted different geostatistical tools to relate geographic layers from various data sources. The overexploitation due to intensive charcoal production to fuel mining activities shaped the current forests by homogenising their structure and species composition into dense and young stands with a reduction in late seral species such as Norway spruce (Picea abies) and an increase in pioneer species such as Mountain pine (Pinus uncinata). The multidisciplinary and multi-scale framework adopted in this study stresses the role of historical landscape ecology in evaluating ecosystem resilience to past anthropogenic disturbances. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13280-022-01750-y

Occupational Exposure to Metal Engineered Nanoparticles: A Human Biomonitoring Pilot Study Involving Italian Nanomaterial Workers

Advances in nanotechnology have led to an increased use of engineered nanoparticles (ENPs) and the likelihood for occupational exposures. However, how to assess such exposure remains a challenge. In this study, a methodology for human biomonitoring, based on Single Particle Inductively Coupled Plasma Mass Spectrometry (SP-ICP-MS), was developed as a tool to assess the ENPs exposure of workers involved in nanomaterial activities in two Italian Companies. The method was validated for size and number concentration determination of Ag, Au, In2O3, Ir, Pd, Pt, and TiO2 NPs in urine and blood samples. The results showed the presence of In2O3 NPs in blood of exposed workers (mean, 38 nm and 10,371 particles/mL), but not in blood of controls. Silver, Au, and TiO2 NPs were found in urine (mean, Ag 29 nm and 16,568 particles/mL) or blood (mean, Au 15 nm and 126,635 particles/mL; TiO2 84 nm and 27,705 particles/mL) of workers, though these NPs were found also in controls. The presence of ENPs in both workers and controls suggested that the extra-professional exposure is a source of ENPs that cannot be disregarded. Iridium, Pd, and Pt NPs were not detected neither in blood nor in urine. Overall, the findings provided a rational basis to evaluate the exposure assessment to ENPs in cohorts of workers as part of risk assessment and risk management processes in workplaces

Influence of Exposure to Benzo[a]pyrene on Mice Testicular Germ Cells during Spermatogenesis

The objective of this study was to assess the toxicological effect of exposure to benzo(a)pyrene, B[a]P, on germ cells during spermatogenesis. Mice were exposed to B[a]P at 1, 10, 50, and 100 mg/kg/day for 30 days via oral ingestion. Germ cells, including spermatogonia, spermatocytes, pachytene spermatocytes, and round spermatids, were recovered from testes of mice exposed to B[a]P, while mature spermatozoa were isolated from vas deferens. Reproductive organs were collected and weighed. Apoptotic response of germ cells and mature spermatozoa were qualified using the terminal deoxynucleotidyl transferase mediated deoxy-UTP nick end labeling (TUNEL) assay. B[a]P exposure at ≤10 mg/kg/day for 30 days did not significantly alter concentrations of germ cells and mature spermatozoa and apoptotic response in germ cells and mature spermatozoa. Exposure to B[a]P at 50 and 100 mg/kg/day induced testicular atrophy and yielded a significant reduction in the concentrations of spermatogonia, spermatocytes, pachytene spermatocytes, and round spermatid cells as compared with the control. Also, mature spermatozoa experienced decreased concentrations and viability. B[a]P-exposed mice experienced a significant increase in apoptotic germ cells as compared to the control mice. However, the mice dose concentrations were not relevant for comparison to human exposure

How accurate are pedotransfer functions for bulk density for Brazilian soils?

The aim of this study was to evaluate the predictive capability of PTFs available in the literature to estimate soil pb in different regions of Brazil, using different metrics (mean absolute error (MAE), root mean squared error (RMSE), mean error (ME) and regression error characteristic (REC) curve)

Risk of developmental delay increases exponentially as gestational age of preterm infants decreases:a cohort study at age 4 years

Aim The aim of the study was to assess the influence of decreasing gestational age on the risk of developmental delay in various domains at age 4 years among children born at a wide range of gestational ages. Method In a community-based cohort, the parents of 1439 preterm-born children (24 0/7 to 35 6/7wks) and 544 term-born children (38 0/7 to 41 6/7wks) born in 2002 and 2003 completed the Ages and Stages Questionnaire (ASQ) when their child was 3 years 7 months to 4 years 1 month old. The prevalence rates of abnormal scores on the ASQ-total problems scale were compared in preterm and term-born children and the resulting odds ratios for gestational age groups were calculated and adjusted for social and biological covariates. Results The prevalence rates of abnormal scores on the ASQ-total problems scale increased with decreasing gestational age: from 4.2% among term-born children to 37.5% among children born at 2425 weeks gestation (p Interpretation The risk of developmental delay increases exponentially with decreasing gestational age below 36 weeks gestation on all developmental domains of the ASQ. Adjustment for covariates did not alter the pattern of exponential increase in developmental risk with decreasing gestational age. We speculate that both direct perinatal cerebral injuries and tropic and maturational brain disturbances are involved

Growth of Preterm and Full-Term Children Aged 0-4 Years:Integrating Median Growth and Variability in Growth Charts

Objectives To assess the distribution of height, weight, and head circumference (HC) in preterm infants for ages 0-4 years, by gestational age (GA) and sex, and to construct growth reference charts for preterm-born children, again by GA and sex, for monitoring growth in clinical practice. Study design The community-based cohort study covered a quarter of The Netherlands. 1690 preterm infants (GA, 25-35(+6) weeks) and a random sample of 634 full-term control infants (GA 38-41(+6)), who were followed from birth to 4 years of age. Height, weight, and HC were regularly assessed during routine well-child visits and data were retrospectively collected. Results At all ages, the median height and weight of preterm children were lower compared with full-term children. Growth depended on the child's GA. Increase in HC showed an early catch-up and was similar to full-term children by the age of 1. Height, weight, and HC were more variable in boys, particularly in the very preterm children. Conclusions At 0 to 4 years, the growth of preterm children differed from that of full-term children and depended on their GA. The greater variability of growth in boys suggests that they are more vulnerable to the complications of preterm birth that influence growth. These growth charts are the most precise tools currently available for monitoring growth in preterm children. (J Pediatr 2012;161:460-5)