Sperm quality of rats exposed to difenoconazole using classical parameters and surface-enhanced Raman scattering: classification performance by machine learning methods

Application and Progress of Machine Learning in Pesticide Hazard and Risk Assessment

Long-term exposure to pesticides is associated with the incidence of cancer. With the exponential increase in the number of new pesticides being synthesized, it becomes more and more important to evaluate the toxicity of pesticides by means of simulated calculations. Based on existing data, machine learning methods can train and model the predictions of the effects of novel pesticides, which have limited available data. Combined with other technologies, this can aid the synthesis of new pesticides with specific active structures, detect pesticide residues, and identify their tolerable exposure levels. This article mainly discusses support vector machines, linear discriminant analysis, decision trees, partial least squares, and algorithms based on feedforward neural networks in machine learning. It is envisaged that this article will provide scientists and users with a better understanding of machine learning and its application prospects in pesticide toxicity assessment.

Chronic exposure to tebuconazole alters thyroid hormones and plumage quality in house sparrows (Passer domesticus)

Triazoles belong to a family of fungicides that are ubiquitous in agroecosystems due to their widespread use in crops. Despite their efficiency in controlling fungal diseases, triazoles are also suspected to affect non-target vertebrate species through the disruption of key physiological mechanisms. Most studies so far have focused on aquatic animal models, and the potential impact of triazoles on terrestrial vertebrates has been overlooked despite their relevance as sentinel species of contaminated agroecosystems. Here, we examined the impact of tebuconazole on the thyroid endocrine axis, associated phenotypic traits (plumage quality and body condition) and sperm quality in wild-caught house sparrows (Passer domesticus). We experimentally exposed house sparrows to realistic concentrations of tebuconazole under controlled conditions and tested the impact of this exposure on the levels of thyroid hormones (T3 and T4), feather quality (size and density), body condition and sperm morphology. We found that exposure to tebuconazole caused a significant decrease in T4 levels, suggesting that this azole affects the thyroid endocrine axis, although T3 levels did not differ between control and exposed sparrows. Importantly, we also found that exposed females had an altered plumage structure (larger but less dense feathers) relative to control females. The impact of tebuconazole on body condition was dependent on the duration of exposure and the sex of individuals. Finally, we did not show any effect of exposure to tebuconazole on sperm morphology. Our study demonstrates for the first time that exposure to tebuconazole can alter the thyroid axis of wild birds, impact their plumage quality and potentially affect their body condition. Further endocrine and transcriptomic studies are now needed not only to understand the underlying mechanistic effects of tebuconazole on these variables, but also to further investigate their ultimate consequences on performance (i.e. reproduction and survival).

Recent development of surface-enhanced Raman scattering for biosensing

Surface-Enhanced Raman Scattering (SERS) technology, as a powerful tool to identify molecular species by collecting molecular spectral signals at the single-molecule level, has achieved substantial progresses in the fields of environmental science, medical diagnosis, food safety, and biological analysis. As deepening research is delved into SERS sensing, more and more high-performance or multifunctional SERS substrate materials emerge, which are expected to push Raman sensing into more application fields. Especially in the field of biological analysis, intrinsic and extrinsic SERS sensing schemes have been widely used and explored due to their fast, sensitive and reliable advantages. Herein, recent developments of SERS substrates and their applications in biomolecular detection (SARS-CoV-2 virus, tumor etc.), biological imaging and pesticide detection are summarized. The SERS concepts (including its basic theory and sensing mechanism) and the important strategies (extending from nanomaterials with tunable shapes and nanostructures to surface bio-functionalization by modifying affinity groups or specific biomolecules) for improving SERS biosensing performance are comprehensively discussed. For data analysis and identification, the applications of machine learning methods and software acquisition sources in SERS biosensing and diagnosing are discussed in detail. In conclusion, the challenges and perspectives of SERS biosensing in the future are presented.

Difenoconazole Exposure Induces Retinoic Acid Signaling Dysregulation and Testicular Injury in Mice Testes

Difenoconazole (DFZ) is a broad-spectrum triazole fungicide that is widely utilized in agriculture. Although DFZ has been demonstrated to induce reproductive toxicity in aquatic species, its toxic effects on the mammalian reproductive system have yet to be fully elucidated. In vivo, male mice were administered 0, 20 or 40 mg/kg/d of DFZ via oral gavage for 35 days. Consequently, DFZ significantly decreased testicular organ coefficient, sperm count and testosterone levels, augmented sperm malformation rates, and elicited histopathological alterations in testes. TUNEL assay showed increased apoptosis in testis. Western blotting results suggested abnormally high expression of the sperm meiosis-associated proteins STRA8 and SCP3. The concentrations of retinoic acid (RA), retinaldehyde (RE), and retinol (ROL) were increased in the testicular tissues of DFZ-treated groups. The mRNA expression level of genes implicated in RA synthesis significantly increased while genes involved in RA catabolism significantly decreased. In vitro, DFZ reduced cell viability and increased RA, RE, and ROL levels in GC-2 cells. Transcriptome analysis revealed a significant enrichment of numerous terms associated with the RA pathway and apoptosis. The qPCR experiment verified the transcriptome results. In conclusion, our results indicate that DFZ exposure can disrupt RA signaling pathway homeostasis, and induce testicular injury in mice testes.

Machine learning-augmented surface-enhanced spectroscopy toward next-generation molecular diagnostics

The world today is witnessing the significant role and huge demand for molecular detection and screening in healthcare and medical diagnosis, especially during the outbreak of COVID-19. Surface-enhanced spectroscopy techniques, including Surface-Enhanced Raman Scattering (SERS) and Infrared Absorption (SEIRA), provide lattice and molecular vibrational fingerprint information which is directly linked to the molecular constituents, chemical bonds, and configuration. These properties make them an unambiguous, nondestructive, and label-free toolkit for molecular diagnostics and screening. However, new issues in molecular diagnostics, such as increasing molecular species, faster spread of viruses, and higher requirements for detection accuracy and sensitivity, have brought great challenges to detection technology. Advancements in artificial intelligence and machine learning (ML) techniques show promising potential in empowering SERS and SEIRA with rapid analysis and automatic data processing to jointly tackle the challenge. This review introduces the combination of ML and SERS/SEIRA by investigating how ML algorithms can be beneficial to SERS/SEIRA, discussing the general process of combining ML and SEIRA/SERS, highlighting the molecular diagnostics and screening applications based on ML-combined SEIRA/SERS, and providing perspectives on the future development of ML-integrated SEIRA/SERS. In general, this review offers comprehensive knowledge about the recent advances and the future outlook regarding ML-integrated SEIRA/SERS for molecular diagnostics and screening.

The effect of conazoles on reproductive organs structure and function – a review

Conazoles are azole antifungals used in agricultural and pharmaceutical products. Exposure to conazole fungicides leads to several toxic endpoints, including reproductive and endocrine. The results of animal experiments have shown that various conazole fungicides at high doses affect the structure and functions of reproductive organs. In males, adverse effects of conazole fungicides are manifested in the testes, prostate, sperm viability, fertility and sexual behaviour. Reduced testis weight, testis atrophy and reduced or absent sperm production were frequently observed. In female genitalia, structural changes in the ovaries and uterus have been observed. The extent of the changes depends on the dose and duration of treatment. Triazoles affected the expression of multiple genes involved in steroid hormone metabolism and modulate enzyme activity of multiple cytochrome P450 (CYP) and other metabolic enzymes in mammalian liver and other tissues. Conazole fungicides act as endocrine disruptors. Conazoles have been reported to reduce oestradiol and testosterone production and to increase progesterone concentration, indicating the inhibition of enzymes involved in the conversion of progesterone to testosterone. The reproductive effects are consistent with impairment of testosterone homeostasis. The disruption in steroid homeostasis is a common mode of action, leading to abnormal reproductive development and diminished reproductive function. At high doses, azole fungicides affect reproductive organs and fertility in several species.

A Framework for Biosensors Assisted by Multiphoton Effects and Machine Learning

The ability to interpret information through automatic sensors is one of the most important pillars of modern technology. In particular, the potential of biosensors has been used to evaluate biological information of living organisms, and to detect danger or predict urgent situations in a battlefield, as in the invasion of SARS-CoV-2 in this era. This work is devoted to describing a panoramic overview of optical biosensors that can be improved by the assistance of nonlinear optics and machine learning methods. Optical biosensors have demonstrated their effectiveness in detecting a diverse range of viruses. Specifically, the SARS-CoV-2 virus has generated disturbance all over the world, and biosensors have emerged as a key for providing an analysis based on physical and chemical phenomena. In this perspective, we highlight how multiphoton interactions can be responsible for an enhancement in sensibility exhibited by biosensors. The nonlinear optical effects open up a series of options to expand the applications of optical biosensors. Nonlinearities together with computer tools are suitable for the identification of complex low-dimensional agents. Machine learning methods can approximate functions to reveal patterns in the detection of dynamic objects in the human body and determine viruses, harmful entities, or strange kinetics in cells.

Application and Progress of Raman Spectroscopy in Male Reproductive System

Raman spectroscopy is a fast-developing, unmarked, non-invasive, non-destructive technique which allows for real-time scanning and sampling of biological samples in situ, reflecting the subtle biochemical composition alterations of tissues and cells through the variations of spectra. It has great potential to identify pathological tissue and provide intraoperative assistance in clinic. Raman spectroscopy has made many exciting achievements in the study of male reproductive system. In this review, we summarized literatures about the application and progress of Raman spectroscopy in male reproductive system from PubMed and Ovid databases, using MeSH terms associated to Raman spectroscopy, prostate, testis, seminal plasma and sperm. The existing challenges and development opportunities were also discussed and prospected.

Ginger reserves testicular spermatogenesis and steroidogenesis in difenoconazole-intoxicated rats by conducting oxidative stress, apoptosis and proliferation

Difenoconazole, a triazole fungicide, can induce reproductive toxicity in aquatic species, but the probable mechanisms of this hazard in mammals are not formally reported. Here, we have examined the possible ameliorative efficiency of the ginger aqueous extract against the reproductive toxicity of difenoconazole in male rats. Thirty-six animals were equally divided into six groups: control, ginger aqueous extract (50 mg/kg), difenoconazole (15 mg/kg), difenoconazole (30 mg/kg) and ginger co-treated with two doses of difenoconazole. Difenoconazole markedly decreased sperm count, motility and normality percentage, together with the Johnson score. Difenoconazole also significantly reduced serum testosterone, luteinizing hormone and follicle-stimulating hormone levels, as well as the activities of testicular steroidogenic acute regulatory protein and 17 β-hydroxysteroid dehydrogenases. Furthermore, difenoconazole brought a significant decrease in the testicular activity of catalase, but it increased the activity of glutathione peroxidase. Moreover, difenoconazole upregulated the testicular transcripts of Bax and caspase-3, increased Ki-67 immunoreactivity and induced histoarchitecture alterations plus DNA damage. Remarkably, ginger co-treatment preserved sperm toxicity, restored hormone profiles, increased steroidogenic activity and prevented oxidative injury-promoted testicular apoptosis. In conclusion, phenolic acids and flavonoids of ginger can reserve spermatogenesis and steroidogenesis in difenoconazole-intoxicated rats by improving testicular redox status, inhibiting apoptosis and refining proliferation capacity.