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Organophosphates are a large class of chemicals with anticholinesterase action insecticides. Dimethoate belongs to the class of organophosphates and it is used for agriculture purpose. Its main toxicological role in animals and humans is the inhibition of the activity of acetylcholinesterase. Although it is not considered genotoxic, carcinogenic and teratogen, there is evidence of increased pup mortality in developmental neurotoxicity studies. Since there is scant published literature about developmental toxicity, we investigated the adverse effects of dimethoate on fertilization and embryonic development in sea urchin (Paracentrotus lividus), a model organism widely used to assess the toxicity of contaminants on environmental matrices; so pesticide residues can be released into the environment, and could affect the health of organisms, including humans. Different solution of dimethoate (4 × 10−3, 4 × 10−4, 4 × 10−5, 4 × 10−6 and 4 × 10−7 g/10 ml) have been tested on spermatozoa of P. lividus to evaluate the fertilizing ability of them when we added egg cells untreated. We demonstrated that dimethoate does not interfere with fertilizing ability of spermatozoa but egg cells fertilized by treated spermatozoa showed alterations in the segmentation planes as asymmetric and/or asynchronous cell divisions.

The use of paper-based methods for clinical diagnostics is a rapidly expanding research topic attracting a great deal of interest. Some groups have attempted to realize an integrated nucleic acid test on a single microfluidic paper chip, including extraction, amplification, and readout functions. However, these studies were not able to overcome complex modification and fabrication requirements, long turn-around times, or the need for sophisticated equipment like pumps, thermal cyclers, or centrifuges. Here, we report an extremely simple paper-based test for the point-of-care diagnosis of rotavirus A, one of the most common pathogens that causes pediatric gastroenteritis. This paper-based test could perform nucleic acid extraction within 5 min, then took 25 min to amplify the target sequence, and the result was visible to the naked eye immediately afterward or quantitative by the UV–Vis absorbance. This low-cost method does not require extra equipment and is easy to use either in a lab or at the point-of-care. The detection limit for rotavirus A was found to be 1 × 103 copies/mL. In addition, 100% sensitivity and specificity were achieved when testing 48 clinical stool samples. In conclusion, the present paper-based test fulfills the main requirements for a point-of-care diagnostic tool, and has the potential to be applied to disease prevention, control, and precision diagnosis.

DNA analysis is essential for diagnosis and monitoring of many diseases. Conventional DNA testing is generally limited to the laboratory. Increasing access to relevant technologies can improve patient care and outcomes in both developed and developing regions. Here, we demonstrate direct DNA analysis in paper-based devices, uniquely enabled by ion concentration polarization at the interface of patterned nanoporous membranes in paper (paper-based ICP). Hepatitis B virus DNA targets in human serum are simultaneously preconcentrated, separated, and detected in a single 10 min operation. A limit of detection of 150 copies/mL is achieved without prior viral load amplification, sufficient for early diagnosis of hepatitis B. We clinically assess the DNA integrity of sperm cells in raw human semen samples. The percent DNA fragmentation results from the paper-based ICP devices strongly correlate (R(2) = 0.98) with the sperm chromatin structure assay. In all cases, agreement was 100% with respect to the clinical decision. Paper-based ICP can provide inexpensive and accessible advanced molecular diagnostics.

In a retrospective study, the results from 786 samples of alleged sexual assaults during a 5-year period were evaluated. Of the samples, 758 were from female victims and 28 were from male victims. The material examined during this 5-year period consisted of 561 cotton swabs with swabs taken from the genitals, mouth, anus, or skin surface. In addition, textile products were examined 191 times, paper products 23 times, and other evidentiary materials 11 times. The acid phosphatase (acP) test was performed as a preliminary test for all samples, followed by microscopy after Baecchi staining. DNA analysis was performed on 74 samples following individual court orders. The retrospectively evaluated results from this period indicate that additional tests for the detection of sperm on textiles and paper products are dispensable after a negative acP test. This is different for genital swabs, since sperm could be found microscopically in 3% of cases with a negative acP test, and DNA analysis was also successful. However, an individual investigative strategy has to be determined for each case, as, depending on the structure of the case, the evidence of male DNA on a female victim, or on her clothes, for instance, can also have evidentiary value without microscopic proof for sperm.

Isocode card and IsoCode ID Sample Registration Matrix (Schleicher and Schuell BioScience Inc.) are different paper devices chemically treated that keep sample DNA safe from degradation, allowing for the indefinite storage of DNA at ambient temperatures. In this study, blood was collected on Isocode card while saliva, sperm were collected on IsoCode ID. We also tried to verify the effect of collecting urine on Isocode ID. All samples (belonging to the same male donor) were analyzed after 1 day, 1-5 months since their application on the paper.

The authors suggest the use of Baecchi's staining for the morphological demonstration of spermatozoa on paper tissues. They affirm that the method suggested allows good results to be obtained even using material abandoned at the site of sexual aggression.

A blot-immunobinding test was used to detect anti-sperm antibodies in human sera and to identify the corresponding auto- or iso-antigens on human sperm. A high proportion of sera at a 1:100 dilution from fertile persons, as well as infertile patients, contains antibodies reactive with sperm. This phenomenon might be physiological. At 1:2,000 dilution, a higher binding capacity was detected in the sera from infertile groups, but a few fertile persons were also positive. Antibodies to a single antigenic determinant with Mr of approximately 14,000 were found in a significantly higher proportion among males with unexplained infertility.

Two monoclonal antibodies (16 D3 and 24 E3) were used to map tubulin domains in human spermatozoa by indirect immunofluorescence. Their specificity to tubulin in these cells was established by Western blotting. Whereas 16 D3 uniformly stained the principal piece of the flagellum, the staining provided by 24 E3 decreased along the tail to become very weak 30 micron further away from the midpiece. This latter antibody also reacted with the proximal centriole as well as the midpiece, but not all spermatozoa stained identically at this level indicating heterogeneity within the population of sperm cells from a given donor. 16 D3 reacted weakly with the head, and the staining was interrupted after a bright spot in the neck. The study of a pathological case (the short tail spermatozoon) with an abnormal arrangement of dense fibers was consistent with a correlation between the distribution of the epitope defined by 24 E3 and that of peri-axenomal structures. The existence of tubulin domains interacting with these structures is postulated.