Search Results (24)

Early pregnancy diagnosis is a key component of reproductive management in swine production systems. Accurate identification of pregnant and non-pregnant sows within the first 30 days after insemination allows timely reproductive decisions and reduces non-productive days. The present systematic review evaluates the diagnostic efficiency of ultrasonographic and progesterone-based methods used for early detection of pregnancy in sows. A structured literature search was conducted in accordance with the PRISMA Statement guidelines, using major scientific databases. Studies evaluating pregnancy diagnosis in sows within the first 30 days after insemination were included. Diagnostic approaches were analyzed with respect to methodological design, timing of examination, biological sample matrix, and reported indicators of diagnostic accuracy. Ultrasonographic techniques have evolved from early acoustic detection in A-mode to real-time imaging in B-mode and more recently algorithm-assisted interpretation of ultrasound images. Real-time ultrasonography allows direct visualization of gestational structures; in one study, diagnostic accuracy above 95% was reported after approximately 23–24 days of pregnancy under optimal examination conditions. Progesterone-based analyses evaluate luteal endocrine activity and are particularly useful for early identification of non-pregnant animals after luteolysis. The diagnostic efficiency of hormonal assays depends strongly on the timing of sampling and the biological matrix used for analysis, including plasma, serum, dried blood spots, saliva, or feces. The comparative analysis shows that ultrasonography provides morphological confirmation of pregnancy, whereas progesterone analyses serve mainly as functional indicators of luteal activity. These methods play complementary roles in reproductive management. Ultrasonography remains the most reliable method for confirming pregnancy, while progesterone-based analyses are valuable tools for early reproductive screening and identification of non-pregnant sows. Full article

The use of dried matrix spots (DMSs) has recently re-emerged as a useful sample storage technique and analytical platform along with the increased adoption of and general preference for ambient ionization mass-spectrometric methods. However, challenges associated with precise liquid confinement and sample targeting persist. In this paper, we present a laser micromachining-based approach to prepare DMSs on hydrophobic paper substrates that include visual recognition elements, or reticles, around surface energy traps (SETs). This targeted DMS substrate is combined with direct mass spectrometric analyses, namely liquid microjunction–surface sampling probe–mass spectrometry (LMJ-SSP-MS) and flowing atmospheric-pressure afterglow–mass spectrometry (FAPA-MS). With the laser-based micromachining approach, DMSs flanked by crosshairs for enhanced visualization are prepared on SETs as small as 0.55 mm in diameter, which offers an approximately 12-fold reduction in size compared to traditional DMS preparations. The DMSs prepared on these targeting SETs are demonstrated with the detection of caffeine in model aqueous and artificial urine solutions using LMJ-SSP-MS and FAPA-MS, respectively. With further refinement, this approach could be automated using computer vision and robotics to broaden the scope of DMSs and improve the analytical workflow. Full article

Dried matrix spot (DMS) techniques have gained increasing attention in bioanalytical and forensic toxicology for the detection of opiates and opioids, offering minimally invasive sampling, enhanced sample stability, and simplified storage and transport. This review provides a critical overview of recent methodological advances and applications of DMS across multiple biological matrices, including blood, plasma, urine, and oral fluid. Particular focus is given to sample preparation protocols, extraction strategies, analytical instrumentation, and method performance. Dried blood spots (DBS) remain the most established format; however, alternative matrices such as dried plasma, urine, and saliva spots (DPS, DUS, DSS) are expanding the scope of DMS, particularly in decentralised and point-of-care contexts. Despite clear advantages, such as reduced biohazard risk and compatibility with high-throughput workflows, several limitations persist, including low sample volumes, matrix-specific recovery issues, and lack of standardised procedures. Future efforts should aim to optimise paper substrates, improve solvent–matrix compatibility, and integrate DMS workflows with automated or miniaturised mass spectrometry platforms. Overall, DMS techniques represent a versatile and evolving analytical platform with strong potential for reliable opioid monitoring in both clinical and forensic settings. Full article

Xerostomia, the subjective complaint of a dry mouth, is frequently associated with salivary flow reduction and/or salivary gland hypofunction. This condition significantly impacts an individual’s quality of life and oral health, including difficulties in speaking, chewing, and swallowing. Xerostomia may be caused by autoimmune diseases, xerogenic medications, and radiation therapy. Our objective was to identify differentially expressed proteins in the saliva of patients with medication and autoimmune disease-associated xerostomia compared to non-xerostomic control subjects. Two groups of individuals (N = 45 total) were recruited: non-xerostomic subjects (NX-group; n = 18) and xerostomic patients (XP-group; n = 27). Dried saliva spot samples were collected from major salivary glands, i.e., parotid (left and right) and submandibular glands. Proteomic analysis was performed by deep nanoLC-MS/MS. Differential protein expression in the XP-group relative to the NX-group was determined by the Mann–Whitney U-test with FDR Benjamini–Hochberg correction (p_adj < 0.05). The Search Tool for Recurring Instances of Neighboring Genes (STRING_v12.0) was used to generate interaction networks and perform pathway analysis. A total of 1407 proteins were detected. Of these, 86 from the left parotid gland, 112 from the right parotid gland, and 73 from the submandibular gland were differentially expressed proteins (DEPs). Using STRING analysis, we identified, for the first time, several neurodegenerative disease-associated networks, primarily involving the downregulation of the 20S proteasome core complex and glyoxalase proteins across salivary glands. In this study, we determined neuronal dysregulation and impaired methylglyoxal (MGO) detoxification, possibly through reduced protein expression of glyoxalase Parkinson’s Disease (PD) Protein 7 (encoded by the PARK7 gene) in major salivary glands of xerostomic patients. Indeed, impaired MGO detoxification has been previously shown to cause salivary gland dysfunction in a mouse model of type 2 diabetes. Based on other DEPs associated with neurodegenerative disorders, our results also suggest a possible deficiency in the parasympathetic nervous system innervation of salivary glands, warranting further investigation. Full article

Background/Objectives: Epilepsy affects approximately 50 million people worldwide, with antiepileptic drugs (AEDs) remaining the cornerstone of treatment. Due to their narrow therapeutic windows, AEDs are ideal candidates for therapeutic drug monitoring (TDM). Oral fluid is increasingly considered a viable alternative to blood and urine, as it reflects the free (active) concentration of many AEDs. Its non-invasive collection, which does not require trained personnel, makes it particularly suitable for TDM in paediatric and geriatric populations. However, as samples are often stored for extended periods before analysis, analyte stability becomes a critical concern. This study aimed to evaluate the stability of four commonly used AEDs in dried saliva spot (DSS) samples. Methods: Phenobarbital, phenytoin, carbamazepine, and carbamazepine-10,11-epoxide were analysed in oral fluid samples collected via spitting and stored as DSSs. Quantification was performed using high-performance liquid chromatography with diode array detection (HPLC-DAD). Design of experiments tools were used to assess the effects of preservatives, storage temperatures, light exposure, and storage durations on analyte stability. Results: Optimal conditions were refrigeration in the dark, with a low concentration of ascorbic acid as preservative. Samples at 10 µg/mL remained stable for 14 days longer than those without preservative or reported in previous studies. Unexpectedly, at 0.5 µg/mL, analytes in samples without preservative showed greater stability. Conclusions: To our knowledge, this is the first study combining DSS and HPLC-DAD to assess the stability of these AEDs in oral fluid, providing valuable insights for non-invasive TDM strategies and supporting the feasibility of saliva-based monitoring in clinical settings. Full article

The analysis of biological fluids plays a crucial role in biomarker discovery, disease diagnostics, and precision medicine. Dried sample carriers—such as dried blood spots, dried plasma, serum, saliva, tears, and urine—have emerged as powerful tools, offering advantages in sample collection, storage, and transport, particularly in remote and resource-limited settings. Recent advances in proteomic methodologies have expanded the potential of these dried matrices, yet challenges related to protein stability, sensitivity, and standardization persist. This review critically examines the current state of proteomic investigations using dried biological fluids. Furthermore, we compare proteomics’ progress in this field with other omics approaches, such as metabolomics, to contextualize its development and integration potential. While dried fluid proteomics is promising for non-invasive diagnostics and large-scale epidemiological studies, addressing technical limitations will be essential for its broader adoption in clinical and translational research. Full article

Background: The Safety and Immunogenicity of COVID-19 Vaccines in Systemic Autoimmune-Mediated Inflammatory Diseases (SUCCEED) study was created to better understand COVID-19 vaccination in immune-mediated inflammatory disease (IMID). Knowing the frequency of COVID-19 breakthrough infections is important, particularly in IMID. Our objective was to assess these events in IMID. Methods: We prospectively studied IMID participants who had received ≥three COVID-19 vaccine doses. Individuals provided saliva samples monthly (September 2022 to August 2023). These were evaluated by polymerase chain reaction (PCR) for SARS-CoV-2. We also assessed antibodies against SARS-CoV-2 (anti-spike, SmT1, receptor binding domain, RBD, and nucleocapsid, NP) based on dried blood spots. Multivariable general estimating equation regression produced odd ratios (OR) for PCR SARS-CoV-2 positivity, related to demographics, immunosuppressives, and antibody levels. Results: Diagnoses included rheumatoid arthritis RA (N = 161, 44% of the total), systemic lupus, psoriatic arthritis, spondylarthritis, vasculitis, systemic sclerosis, and inflammatory bowel disease. Of the 366 participants, most were taking immunosuppressive medication. Of 1266 saliva samples, 56 (5.1%) were positive for SARS-CoV-2 on PCR. Higher anti-SmT1 antibodies were inversely associated with SARS-CoV-2 detection on PCR (adjusted OR 0.66, 95% confidence interval 0.45–0.97). Antibodies to SmT1, RBD, and NP were correlated and thus could not be included in a single model, but when anti-RBD was used in place of anti-SmT1, the results were similar. No other factor (including prior COVID-19 infection) was clearly associated with SARS-CoV-2 detection. Conclusions: This is the first study of SARS-CoV-2 in a large prospective cohort of triple (or more) vaccinated individuals with IMIDs. Anti-SmT1 antibodies appeared to be protective against later SARS-CoV-2 positivity, although recent past infection was not clearly related. This suggests the importance of maintaining robust vaccine-induced immunity through vaccination in IMID. Full article

Volumetric absorptive microsampling (VAMS) is an emerging technique in clinical and forensic toxicology. It is recognized as a promising alternative to traditional sampling methods, offering an accurate and minimally invasive means of collecting small volumes of biological samples, such as blood, urine, and saliva. Unlike conventional methods, VAMS provides advantages in terms of sample stability, storage, and transportation, as it enables samples to be collected outside laboratory environments without requiring refrigeration. This review explores several VAMS methodologies, with a particular focus on its application for the quantification of drugs and other substances in clinical and forensic toxicology. It compares VAMS to other microsampling techniques, such as dried blood spots (DBSs), highlighting VAMS’s superiority in addressing issues related to sample volume consistency and environmental impact. Despite its advantages, VAMS also presents certain limitations, including higher costs and difficulties in detecting underfilled samples. Overall, VAMS stands out as a microsampling technique with the potential to enhance patient compliance and operational efficiency, positioning itself as a viable tool for toxicological analysis in both clinical and forensic contexts. Full article

Zika virus (ZIKV) can cause neurological issues in infants. To provide protection, neutralizing antibodies should be transferred from the mother to the infant. We conducted a study at the Hospital General de Pochutla, Oaxaca, Mexico. Samples were collected from mothers (blood and breast milk) and infants (saliva and dried blood spots) within the first 12 postnatal hours (December 2017 to February 2018) and tested for ZIKV total and neutralizing antibodies as well as ZIKV-PCR. Microcephaly was evaluated according to INTERGROWTH-21st standards. Maternal IgG seroprevalence was 28.4% with 10.4% active infection, while infant IgG seroprevalence was 5.5% with 2.4% active infection. There were two cases of virolactia, and 6.3% of the infant saliva samples tested positive for ZIKV. Additionally, 18.3% of the infants were in a cephalic perimeter percentile lower than 10 and had an association between microcephaly and serology or a PCR between 8.6 and 60.9%. The infant blood samples had neutralizing antibodies, indicating intrauterine protection. Microcephaly was correlated with serology or PCR, but in our study population, non-ZIKV factors may be involved as well. Low ZIKV infection values in breast milk mean that breastfeeding is safe in most of the mothers and infants of the endemic area studied. Full article

Congenital cytomegalovirus (cCMV) infection is a leading cause of sensorineural hearing loss (SNHL) and neurodevelopmental disabilities in children worldwide. Some regions in the United States and Canada have implemented universal newborn screening for cCMV, which requires molecular diagnostic technologies for identifying cCMV, such as PCR testing of newborn dried blood spots (DBS). This study aimed to evaluate the sensitivity of droplet digital PCR (ddPCR) compared to quantitative real-time PCR to detect CMV DNA in newborn DBS. The limit of detection of various ddPCR primer/probe combinations (singleplex UL55-HEX, singleplex UL83-FAM, and multiplex UL55-HEX/UL83-FAM) was evaluated using the National Institute of Standards and Technology’s (NIST) CMV quantitative standard. Singleplex UL55-HEX ddPCR exhibited the lowest limit of detection among the primer/probe combinations tested for ddPCR. UL55 ddPCR was then compared to real-time PCR in 49 infants with confirmed cCMV identified through newborn screening for CMV in saliva swabs and confirmed by a urine test. The results showed that ddPCR was only positive for 59% (29 out of 49) of the cCMV infants, while real-time PCR was positive for 80% (39 out of 49). Due to its lower sensitivity and throughput, ddPCR may not be suitable for cCMV newborn screening. Full article

The collection of dried blood spots (DBS) facilitates newborn screening for a variety of rare, but very serious conditions in healthcare systems around the world. Sub-punches of varying sizes (1.5–6 mm) can be taken from DBS specimens to use as inputs for a range of biochemical assays. Advances in DNA sequencing workflows allow whole-genome sequencing (WGS) libraries to be generated directly from inputs such as peripheral blood, saliva, and DBS. We compared WGS metrics obtained from libraries generated directly from DBS to those generated from DNA extracted from peripheral blood, the standard input for this type of assay. We explored the flexibility of DBS as an input for WGS by altering the punch number and size as inputs to the assay. We showed that WGS libraries can be successfully generated from a variety of DBS inputs, including a single 3 mm or 6 mm diameter punch, with equivalent data quality observed across a number of key metrics of importance in the detection of gene variants. We observed no difference in the performance of DBS and peripheral-blood-extracted DNA in the detection of likely pathogenic gene variants in samples taken from individuals with cystic fibrosis or phenylketonuria. WGS can be performed directly from DBS and is a powerful method for the rapid discovery of clinically relevant, disease-causing gene variants. Full article

A universal screening research study was conducted in six hospitals to identify the clinical sensitivity of polymerase chain reaction (PCR) testing on newborn dried blood spots (DBSs) versus saliva specimens for the diagnosis of congenital cytomegalovirus (cCMV). CMV DNA positive results from DBSs or saliva were confirmed with urine testing. Findings of several false-positive (FP) saliva PCR results prompted an examination of a possible association with donor milk. Documentation of the frequency of positive saliva results, including both true-positive (TP) and FP status from clinical confirmation, occurred. The frequency of donor milk use was compared for TP and FP cases. Of 22,079 participants tested between 2016 and 2022, 96 had positive saliva results, 15 were determined to be FP, 79 TP, and 2 were excluded for incomplete clinical evaluation. Newborn donor milk use was identified for 18 (19.14%) of all the positive saliva screens. Among the 15 FPs, 11 (73.33%) consumed donor milk compared to 7 of the 79 TPs (8.8%) (OR 28.29, 95% CI 7.10–112.73, p < 0.001). While milk bank Holder pasteurization inactivates CMV infectivity, CMV DNA may still be detectable. Due to this possible association, screening programs that undertake testing saliva for CMV DNA may benefit from documenting donor milk use as a potential increased risk for FP results. Full article

Therapeutic drug monitoring (TDM) is a specialized area of laboratory medicine which involves the measurement of drug concentrations in biological fluids with the aim of optimizing efficacy and reducing side effects, possibly modifying the drug dose to keep the plasma concentration within the therapeutic range. Plasma and/or whole blood, usually obtained by venipuncture, are the “gold standard” matrices for TDM. Microsampling, commonly used for newborn screening, could also be a convenient alternative to traditional sampling techniques for pharmacokinetics (PK) studies and TDM, helping to overcome practical problems and offering less invasive options to patients. Although technical limitations have hampered the use of microsampling in these fields, innovative techniques such as 3-D dried blood spheroids, volumetric absorptive microsampling (VAMS), dried plasma spots (DPS), and various microfluidic devices (MDS) can now offer reliable alternatives to traditional samples. The application of microsampling in routine clinical pharmacology is also hampered by the need for instrumentation capable of quantifying analytes in small volumes with sufficient sensitivity. The combination of microsampling with high-sensitivity analytical techniques, such as liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), is particularly effective in ensuring high accuracy and sensitivity from very small sample volumes. This manuscript provides a critical review of the currently available microsampling devices for both whole blood and other biological fluids, such as plasma, urine, breast milk, and saliva. The purpose is to provide useful information in the scientific community to laboratory personnel, clinicians, and researchers interested in implementing the use of microsampling in their routine clinical practice. Full article

Screening newborns for congenital cytomegalovirus (cCMV) infection is critical for early detection and prompt diagnosis of related long-term consequences of infection, such as sensorineural hearing loss and neurodevelopmental delays. The objective of this study was to describe the validity of different newborn cCMV infection screening approaches and compare the expected number of cCMV cases detected across targeted and universal screening algorithms. The overall sensitivity (OSn) of targeted screening algorithms that required failure of auditory brain stem response and transient evoked otoacoustic emissions (TOAE; two-fail serial testing) or TOAE only (one-fail serial testing) before diagnostic CMV testing using saliva and urine PCR tests was 79% and 88%, respectively. The OSn for two-fail serial testing with diagnostic CMV testing using dried blood spot (DBS) was 75%. In contrast, OSn was 90% for universal screening (saliva and urine PCR tests) and 86% for universal screening with DBS testing alone. Overall, specificities were 100% across all algorithms. Universal screening using DBS testing and universal screening using saliva and urine testing can potentially detect 312 and 373 more cCMV cases per 100,000 live births, respectively, than two-fail serial testing. Overall, implementing universal cCMV newborn screening would improve cCMV detection, ultimately leading to better health outcomes. Full article

Antipsychotics have narrow therapeutic windows, and their monitoring in biological fluids is therefore important; consequently, stability in those fluids must be investigated during method development and validation. This work evaluates the stability of chlorpromazine, levomepromazine, cyamemazine, clozapine, haloperidol, and quetiapine in oral fluid (OF) samples, using the dried saliva spots (DSS) sampling approach and gas chromatography coupled to tandem mass spectrometry. Since many parameters can influence the stability of the target analytes, design of experiments was adopted to check the crucial factors that affect that stability in a multivariate fashion. The studied parameters were the presence of preservatives at different concentrations, temperature, light, and time. It was possible to observe that antipsychotic stability improved when OF samples in DSS were stored at 4 °C, with a low ascorbic acid concentration, and in the absence of light. With these conditions, chlorpromazine and quetiapine were stable for 14 days, clozapine and haloperidol were stable for 28 days, levomepromazine remained stable for 44 days, and cyamemazine was stable for the entire monitored period (146 days). This is the first study that evaluates the stability of these antipsychotics in OF samples after application to DSS cards. Full article