Differential diagnosis between multiple sclerosis and leukodystrophies - A scoping review.

Multiple Sclerosis (MS) is an autoimmune demyelinating disease of the central nervous system (CNS) characterized by damage to the myelin sheaths of oligodendrocytes. Currently, there is no specific biomarker to identify the disease; however, a diagnostic criterion has been established based on patient's clinical, laboratory, and imaging characteristics, which assists in identifying this condition. The primary method for diagnosing MS is the McDonald criteria, first described in 2001 and revised in the years 2005, 2012, and 2017. These criteria have been continuously reviewed to enhance specificity and sensitivity in the diagnosis of MS, thereby reducing errors in its differential diagnosis. An important differential diagnosis that shares overlapping features with MS, mainly the progressive forms, are leukodystrophies with demyelination as underlying pathology. Leukodystrophies comprise a rare group of genetically determined disorders that lead to either demyelination or hypomyelination of the central nervous system that can result neuroimaging changes as well as clinical findings similar to those observed in MS. Thus, systematic evaluation encompassing clinical presentation, neuroimaging findings, and laboratory metrics proves indispensable for a differential diagnosis. As such, this study aimed to establish, clearly and objectively, the similarities and differences between MS and the main demyelinating leukodystrophies. The study analyzed the parameters of the McDonald criteria, including clinical, laboratory, and magnetic resonance imaging aspects, as found in patients with leukodystrophies through scoping literature review. The data were compared with the determinations of the revised 2017 McDonald criteria to facilitate the differential diagnosis of these diseases in clinical practice.

Early pharmacological profiling of isatin derivatives as potent and selective cytotoxic agents.

Isatin derivatives have attracted a lot of interest for their potential in the development of new anticancer drugs. A library of 38 isatin derivatives, created through an Ugi four-component reaction, underwent an initial screening in a panel of six human solid tumor cell lines. The four most active derivatives were then selected for further testing. These compounds showed selectivity towards the non-small cell lung cancer (NSCLC) cell line SW1573, whilst NSCLC A549 cells were barely affected. The combination of phenotypic assays, including wound healing, clonogenic and continuous live cell imaging provided a deeper understanding of the compounds' mode of action. In particular, the latter demonstrated that isatin derivatives were able to induce necroptosis in SW1573 cells. The kinetics of cell death showed that necroptosis appeared after 2.5 h of exposure, which could be delayed to 7 h when co-treated with necrostatin-1. Interaction between the isatin derivatives and the KRAS G12C protein variant was discarded after in silico studies. Further studies are warranted to identify the cellular target responsible for the observed selectivity among cell lines.

Sleep and memory complaints in long COVID: an insight into clustered psychological phenotypes.

This study evaluated clinical features of individuals with long COVID (5-8 months after diagnosis) who reported sleep and memory problems (62 cases) compared to those without (52 controls). Both groups had a similar mean age (41 vs. 39 years). Around 86% of the participants were non-hospitalized at the time of infection, and none of them were vaccinated at that point. Subsequently, both cases and controls received the vaccine; however, the vaccination rates differed significantly between the groups (30.7% vs. 51.0%). Cases and controls had similar rates of symptoms at acute COVID phase. However, cases were more likely to experience coryza, dyspnea, headache, and nausea/vomiting during long COVID. Regarding new-onset symptoms in long COVID, 12.9% of cases had dyspnea, and 14.5% experienced nausea/vomiting, whereas in the control group there were only 1.9% and 0.0%, respectively. Cases also had a significantly higher prevalence of persistent headache (22.6% vs. 7.7%), and dyspnea (12.9% vs. 0.0). In addition, cases also showed an increased rate of mental health complaints: disability in daily activities (45.2% vs. 9.6%; P < 0.001); concentration/sustained attention difficulties (74.2% vs. 9.6%; P < 0.001); anxiety-Generalized Anxiety Disorder 2-item scale (GAD-2) ≥ 3 (66.1% vs. 34.6%; P = 0.0013); and "post-COVID sadness" (82.3% vs. 40.4%; P < 0.001). We observed a significant correlation between sadness and anxiety in cases, which was not observed in controls (P=0.0212; Spearman correlation test). Furthermore, the frequency of concomitant sadness and anxiety was markedly higher in cases compared to controls (59.7% vs. 19.2%) (P < 0.0001; Mann-Whitney test). These findings highlight a noteworthy association between sadness and anxiety specifically in cases. In conclusion, our data identified concurrent psychological phenotypes in individuals experiencing sleep and memory disturbances during long COVID. This strengthens the existing evidence that SARS-CoV-2 causes widespread brain pathology with interconnected phenotypic clusters. This finding highlights the need for comprehensive medical attention to address these complex issues, as well as major investments in testing strategies capable of preventing the development of long COVID sequelae, such as vaccination.

Potential use of two Serratia strains for cadmium remediation based on microbiologically induced carbonate precipitation and their cadmium resistance.

Cadmium (Cd) presence and bioavailability in soils is a serious concern for cocoa producers. Cocoa plants can bioaccumulate Cd that can reach humans through the food chain, thus posing a threat to human health, as Cd is a highly toxic metal. Currently, microbiologically induced carbonate precipitation (MICP) by the ureolytic path has been proposed as an effective technique for Cd remediation. In this work, the Cd remediation potential and Cd resistance of two ureolytic bacteria, Serratia sp. strains 4.1a and 5b, were evaluated. The growth of both Serratia strains was inhibited at 4 mM Cd(II) in the culture medium, which is far higher than the Cd content that can be found in the soils targeted for remediation. Regarding removal efficiency, for an initial concentration of 0.15 mM Cd(II) in liquid medium, the maximum removal percentages for Serratia sp. 4.1.a and 5b were 99.3% and 99.57%, respectively. Their precipitates produced during Cd removal were identified as calcite by X-ray diffraction. Energy dispersive X-ray spectroscopy analysis showed that a portion of Cd was immobilized in this matrix. Finally, the presence of a partial gene from the czc operon, involved in Cd resistance, was observed in Serratia sp. 5b. The expression of this gene was found to be unaffected by the presence of Cd(II), and upregulated in the presence of urea. This work is one of the few to report the use of bacterial strains of the Serratia genus for Cd remediation by MICP, and apparently the first one to report differential expression of a Cd resistance gene due to the presence of urea.

Floor and ceiling effects on the Montreal Cognitive Assessment in patients with Parkinson's disease in Brazil.

Parkinson's disease (PD) is a common neurodegenerative disease associated with cognitive impairment. The Montreal Cognitive Assessment (MoCA) has been used as a recommended global cognition scale for patients with PD, but there are some concerns about its application, partially due to the floor and ceiling effects. Objective: To explore the floor and ceiling effects on the MoCA in patients with PD in Brazil. Methods: Cross-sectional study with data from patients with PD from five Brazilian Movement Disorders Clinics, excluding individuals with a possible diagnosis of dementia. We analyzed the total score of the MoCA, as well as its seven cognitive domains. The floor and ceiling effects were evaluated for the total MoCA score and domains. Multivariate analyses were performed to detect factors associated with floor and ceiling effects. Results: We evaluated data from 366 patients with PD and approximately 19% of individuals had less than five years of education. For the total MoCA score, there was no floor or ceiling effect. There was a floor effect in the abstraction and delayed memory recall domains in 20% of our sample. The ceiling effect was demonstrated in all domains (80.8% more common in naming and 89% orientation), except delayed recall. Education was the main factor associated with the floor and ceiling effects, independent of region, sex, age at evaluation, and disease duration. Conclusion: The floor and ceiling effects are present in specific domains of the MoCA in Brazil, with a strong impact on education. Further adaptations of the MoCA structure for underrepresented populations may reduce these negative effects.

A doença de Parkinson (DP) é uma doença neurodegenerativa comum associada ao declínio cognitivo. A Avaliação Cognitiva de Montreal (Montreal Cognitive Assessment ­ MoCA) tem sido usada como uma escala de cognição global recomendada para pacientes com DP, mas existem algumas preocupações sobre sua aplicação, em parte pelos efeitos solo e teto. Objetivo: Explorar os efeitos solo e teto na MoCA em pacientes com DP no Brasil. Métodos: Estudo transversal com dados de pacientes com DP oriundos de cinco Clínicas de Distúrbios de Movimento no Brasil, excluindo-se pessoas com possível diagnóstico de demência. Nós analisamos a pontuação total da MoCA, assim como a de seus sete domínios cognitivos. Os efeitos solo e teto foram avaliados para a pontuação total da MoCA e seus domínios. Foram feitas análises multivariadas para a detecção de fatores associados os efeitos solo e teto. Resultados: Nós avaliamos dados de 366 pacientes com DP, e aproximadamente 19% das pessoas tinham menos que cinco anos de escolaridade. Para a pontuação total do MoCA, não houve efeito solo ou teto. Houve efeito solo nos domínios abstração e memória de evocação tardia em 20% de nossa amostra. O efeito teto foi demonstrado em todos os domínios (80,8% mais comum em nomeação e 89% orientação), com exceção de memória de evocação tardia. A educação foi o principal fator associado aos efeitos solo e teto, independentemente de região, sexo, idade na avaliação e duração da doença. Conclusão: Os efeitos solo e teto estão presentes em domínios específicos da MoCA no Brasil, com forte impacto da educação. Adaptações adicionais à estrutura da MoCA para populações vulneráveis podem reduzir esses efeitos negativos.

Nanocarriers in Tuberculosis Treatment: Challenges and Delivery Strategies.

The World Health Organization identifies tuberculosis (TB), caused by Mycobacterium tuberculosis, as a leading infectious killer. Although conventional treatments for TB exist, they come with challenges such as a heavy pill regimen, prolonged treatment duration, and a strict schedule, leading to multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains. The rise of MDR strains endangers future TB control. Despite these concerns, the hunt for an efficient treatment continues. One breakthrough has been the use of nanotechnology in medicines, presenting a novel approach for TB treatment. Nanocarriers, such as lipid nanoparticles, nanosuspensions, liposomes, and polymeric micelles, facilitate targeted delivery of anti-TB drugs. The benefits of nanocarriers include reduced drug doses, fewer side effects, improved drug solubility, better bioavailability, and improved patient compliance, speeding up recovery. Additionally, nanocarriers can be made even more targeted by linking them with ligands such as mannose or hyaluronic acid. This review explores these innovative TB treatments, including studies on nanocarriers containing anti-TB drugs and related patents.

Multidimensional chromatography in environmental analysis: Comprehensive two-dimensional liquid versus gas chromatography.

Analysis of complex environmental matrices poses an extreme challenge for analytical chemists due to the vast number of known and unknown compounds, with very diverse chemical and physical properties. The need for a holistic characterisation of this complexity has sparked the development of effective tools to unravel the chemical composition of such environmental samples. Multidimensional chromatographic methods, namely comprehensive two-dimensional (2D) gas and liquid chromatography (GC × GC and LC × LC, respectively), coupled to different detection systems have emerged as powerful tools with the capability to address this challenge. While GC × GC has steadily gained popularity in environmental analysis, LC × LC is surprisingly less attractive in this research field. This critical review article explores the potential reasons why LC × LC is not the dominant technique used in environmental analysis as compared to GC × GC, while simultaneously highlighting the quite unique role of LC × LC for the target and untargeted analysis of complex environmental matrices. The possible combinations of stationary phases, the important role of the interfacing valve as the heart of an LC × LC assembly, the existing optimization strategies for improving the separation power in the 2D chromatographic space, and the need for user-friendly mathematical tools for multidimensional data handling are also discussed. Finally, a set of practical measures are suggested to increase the use and secure the success of LC × LC in environmental analysis.

Shared IVF among female couples: clinical outcomes of the Reception of Oocytes from the Partner (ROPA) method.

RESEARCH QUESTION: What is the population undergoing the ROPA (Reception of Oocytes from Partner) method and what are the outcomes of the technique? DESIGN: Case series of all ROPA treatments carried out between 2011 and 2020 in 18 fertility clinics in Spain. Demographic characteristics, cycle features, laboratory and clinical outcomes, and the intentions regarding the disposition of surplus embryos were analysed. RESULTS: Donor patients were on average 3.5 years younger than recipients (P = 0.001). No significant differences were found in body mass index or anti-Müllerian hormone. In 13% of cases, fertility issues were found: poor ovarian reserve (6.8%); endometriosis (2.9%); and polycystic ovary syndrome (2.2%). Including cases of advanced age (38 years old or older), more than one-half of couples (53.6%) had some condition that could affect fertility. Mean number of mature oocytes per cycle was 10 (+/- 5.7), and fertilization rate was 74.5% (+/- 18.8). Mean number of viable embryos was 3.2 (+/- 1.5). Surplus embryos were cryopreserved in 50.4% of cycles. Outcomes after embryo transfers from ROPA, and subsequent frozen cycles were as follows: positive pregnancy test (61.0%), clinical pregnancy (54.1%) and miscarriage rate (16.1%). Other outcomes were live birth rate per embryo transfer (44.7%); multiple pregnancy rate (5.4%); per cumulative ROPA cycle (48.6%); and per couple (61.6%). CONCLUSION: The outcomes of the ROPA method are reassuring. About one-half of the ROPA cycles resulted in a live birth and one-quarter of the cycles had surplus embryos after achieving a live birth. Main neonatal outcomes were also reassuring.

Altered structural connectivity in olfactory disfunction after mild COVID-19 using probabilistic tractography.

We aimed to investigate changes in olfactory bulb volume and brain network in the white matter (WM) in patients with persistent olfactory disfunction (OD) following COVID-19. A cross-sectional study evaluated 38 participants with OD after mild COVID-19 and 24 controls, including Sniffin' Sticks identification test (SS-16), MoCA, and brain magnetic resonance imaging. Network-Based Statistics (NBS) and graph theoretical analysis were used to explore the WM. The COVID-19 group had reduced olfactory bulb volume compared to controls. In NBS, COVID-19 patients showed increased structural connectivity in a subnetwork comprising parietal brain regions. Regarding global network topological properties, patients exhibited lower global and local efficiency and higher assortativity than controls. Concerning local network topological properties, patients had reduced local efficiency (left lateral orbital gyrus and pallidum), increased clustering (left lateral orbital gyrus), increased nodal strength (right anterior orbital gyrus), and reduced nodal strength (left amygdala). SS-16 test score was negatively correlated with clustering of whole-brain WM in the COVID-19 group. Thus, patients with OD after COVID-19 had relevant WM network dysfunction with increased connectivity in the parietal sensory cortex. Reduced integration and increased segregation are observed within olfactory-related brain areas might be due to compensatory plasticity mechanisms devoted to recovering olfactory function.

Reproductive plans and knowledge of assisted reproductive techniques among lesbian women: an international survey study.

OBJECTIVE: Lesbian couples must resort to adoption or donated semen to achieve parenthood, the latter usually involving assisted reproductive technology. The aim of this study is to assess homosexual women's knowledge about assisted reproductive techniques, the importance of perceived genetic and gestational relationships for their future mother-child bond, as well as their reproductive plans. METHODS: This is an observational study based on an anonymous survey disseminated online in several countries on different continents, addressed to homosexual women. RESULTS: From the 549 participants, most reported being well informed about reproductive options including assisted reproductive technology. The majority want to be a mother as part of a couple, mainly through assisted reproduction or step adoption of their partner's child. The importance of a genetic or gestational relationships with their future child varies greatly between women. Among the sampled women, pregnancy was believed to have a slightly greater impact on the future mother-child connection compared to genetics. CONCLUSIONS: Homosexual women are well informed about the assisted reproductive technology treatments. The majority considers it important to become a mother as a couple, mainly through assisted reproduction or step adoption of their partner's child. The importance given to gestation or genetic mother-child relationships varies greatly between women, and it seems they believe pregnancy may have a slightly greater impact on the future mother-child connection compared to genetics.

Lesbian shared IVF: the ROPA method: a systematic review.

The ROPA (Reception of Oocytes from PArtner) method, also known as lesbian shared IVF (in vitro fertilization), is an assisted reproduction technique for female couples, in which one of the women provides the oocytes (genetic mother) and the other receives the embryo and gestates (gestational mother). As a double parented method, it is the only way lesbian women may biologically share motherhood. This is a narrative review of data concerning ROPA published in PubMed, Scopus, and Cochrane Library. A total of 35 articles were included, 10 about motivations for undergoing ROPA, 13 about ethics or legislation, 4 about motherhood, and 8 studies reporting clinical outcomes. Despite being used for more than a decade, there is a paucity of data regarding this technique in scientific literature. Most women choose this technique to share biological motherhood, but medical issues may also justify its use. Many ethical and legal issues are still to be solved. Despite the small number of studies, data regarding the outcomes of this technique and the resulting motherhood are reassuring.

University students' opinion on gamete donor identification regimes.

PURPOSE: This study aims to evaluate the opinion of university students about the identification or nonidentification of gamete donation and the probability of donation according to the different regimes. METHODS: This was a cross-sectional observational study based on an online anonymous survey including questions about sociodemographic data, reasons for considering donations, information about the donation process and legislation, and their opinions about the different regimes and how they would influence donations. RESULTS: In total, 1393 valid responses were obtained, with a mean age of 24.0 years (SD = 4.8), most of the respondents being female (68.5%), living in a relationship (56.7%), and without children (88.4%). The main reasons for considering donation would be altruism and monetary compensation. Overall, it was found that participants were poorly informed about the donation procedure and legislation. Students revealed preference for nonidentified donation, and they were less likely to donate in an open identity regime. CONCLUSION: Most university students consider themselves poorly informed about gamete donation, express a preference for nonidentified gamete donation, and would less likely donate on an open identity basis. Thus, an identified regime may be less attractive to potential donors and lead to a decrease in the availability of gamete donors.

Female couples undergoing assisted reproduction - choices and the importance of pregnancy and genetics.

OBJECTIVE: To evaluate female couples' reproductive choices, the importance given to genetics and pregnancy and their expectations regarding mother-child relationship. METHODS: Observational study based on an anonymous survey applied to 217 patients during 2021. The survey was given to female couples under reproductive treatment in a private fertility clinic. The outcomes were divided into 3 main groups: the choice of their reproductive treatment, motherhood and biological links, and their plans for future reproductive treatments. RESULTS: Most patients found it easy to choose their treatments and roles. The choice was mainly driven by success rates, costs, and simplicity, except for ROPA for which sharing biological motherhood was the main reason. Most couples consider genetics and pregnancy important but, in the end, they believe they will have a similar connection to their child, regardless of the role played. In the future, some couples consider doing the same treatment while others consider inverting roles. CONCLUSIONS: Most female couples have no difficulty when it comes to choosing a reproductive treatment or role to play, mainly based on costs, success rates and the possibility of sharing biological motherhood with the ROPA method. These patients give great importance to genetics and pregnancy, but they expect a similar connection to their child regardless of the type of treatment and the roles played.

Saccharopolyspora sp. NFXS83 in Marine Biotechnological Applications: From Microalgae Growth Promotion to the Production of Secondary Metabolites.

Marine bacteria are a significant source of bioactive compounds for various biotechnological applications. Among these, actinomycetes have been found to produce a wide range of secondary metabolites of interest. Saccharopolyspora is one of the genera of actinomycetes that has been recognized as a potential source of these compounds. This study reports the characterization and genomic analysis of Saccharopolyspora sp. NFXS83, a marine bacterium isolated from seawater from the Sado estuary in Portugal. The NFXS83 strain produced multiple functional and stable extracellular enzymes under high-salt conditions, showed the ability to synthesize auxins such as indole-3-acetic acid, and produced diffusible secondary metabolites capable of inhibiting the growth of Staphylococcus aureus. Furthermore, when Phaeodactylum tricornutum was co-cultivated with strain NFXS83 a significant increase in microalgae cell count, cell size, auto-fluorescence, and fucoxanthin content was observed. Detailed analysis revealed the presence of clusters involved in the production of various secondary metabolites, including extracellular enzymes, antimicrobial compounds, terpenes, and carotenoids in the genome of strain NFXS83. Ultimately, these findings indicate that Saccharopolyspora sp. NFXS83 has a significant potential for a wide range of marine biotechnological applications.

Parkinson's Disease-Cognitive Rating Scale (PD-CRS): Normative Data and Mild Cognitive Impairment Assessment in Brazil.

Background: The Parkinson's Disease-Cognitive Rating Scale (PD-CRS) assesses posterior-cortical and frontal-subcortical cognitive functioning and distinguishes mild cognitive impairment in Parkinson's disease (PD-MCI); however, it was not evaluated in Brazil. Objectives: To investigate PD-CRS's reliability, validity, normative data, and accuracy for PD-MCI screening in Brazil. Methods: The effects of age, education, and sex on PD-CRS scores were explored. The instrument was tested in 714 individuals (53% female, 21-94 years), with a broad range of education and no neurodegenerative disorder. Trail Making, Consonant Trigrams, Five-Point, and semantic fluency tests were administered for comparison. A second study enrolled patients with PD and intact cognition (n = 44, 59.75 ± 10.79 years) and with PD-MCI (n = 25, 65.76 ± 10.33 years) to investigate criterion validity. PD-CRS subtests were compared with the Cambridge Automated Neuropsychological Battery memory and executive tasks. Results: PD-CRS was unidimensional and reliable (McDonald's ω = 0.83). Using robust multiple regressions, age, and education predicted the total and derived scores in the normative sample. At the 85-point cutoff, PD-MCI was detected with 68% sensitivity and 86% specificity (area under the curve = 0.870). PD-CRS scores strongly correlated with executive and verbal/visual memory tests in both normative and clinical samples. Conclusions: This study investigated the applicability of PD-CRS in the Brazilian context. The scale seems helpful in screening for PD-MCI, with adequate internal consistency and construct validity. The PD-CRS variance is influenced by age and educational level, a critical issue for cognitive testing in countries with educational and cultural heterogeneity.

Isolation of urease-producing bacteria from cocoa farms soils in Santander, Colombia, for cadmium remediation.

Cadmium (Cd) is a toxic heavy metal that causes serious health problems and is present in agriculturally important soils in Colombia, such as the ones used for cocoa farming. Recently, the use of ureolytic bacteria by the Microbiologically Induced Carbonate Precipitation (MICP) activity has been proposed as an alternative to mitigate the availability of Cd in contaminated soils. In this study, 12 urease-positive bacteria able to grow in the presence of Cd(II) were isolated and identified. Three were selected based on urease activity, precipitates formation and growth, with two belonging to the genus Serratia (codes 4.1a and 5b) and one to Acinetobacter (code 6a). These isolates exhibited low urease activity levels (3.09, 1.34 and 0.31 µmol mL-1 h-1, respectively), but could raise the pH to values close to 9.0 and to produce carbonate precipitates. It was shown that the presence of Cd affects the growth of the selected isolates. However, urease activity was not negatively influenced. In addition, the three isolates were observed to efficiently remove Cd from solution. The two Serratia isolates presented maximum removals of 99.70% and 99.62%, with initial 0.05 mM Cd(II) in the culture medium (supplemented with urea and Ca(II)) at 30 °C and 144 h of incubation. For the Acinetobacter isolate, the maximum removal was 91.23% at the same conditions. Thus, this study evidences the potential use of these bacteria for bioremediation treatments in samples contaminated with Cd, and it is one of the few reports that shows the high cadmium removal capacity of bacteria from the genus Serratia. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03495-1.

Plant Growth Promotion, Phytohormone Production and Genomics of the Rhizosphere-Associated Microalga, Micractinium rhizosphaerae sp. nov.

Microalgae are important members of the soil and plant microbiomes, playing key roles in the maintenance of soil and plant health as well as in the promotion of plant growth. However, not much is understood regarding the potential of different microalgae strains in augmenting plant growth, or the mechanisms involved in such activities. In this work, the functional and genomic characterization of strain NFX-FRZ, a eukaryotic microalga belonging to the Micractinium genus that was isolated from the rhizosphere of a plant growing in a natural environment in Portugal, is presented and analyzed. The results obtained demonstrate that strain NFX-FRZ (i) belongs to a novel species, termed Micractinium rhizosphaerae sp. nov.; (ii) can effectively bind to tomato plant tissues and promote its growth; (iii) can synthesize a wide range of plant growth-promoting compounds, including phytohormones such as indole-3-acetic acid, salicylic acid, jasmonic acid and abscisic acid; and (iv) contains multiple genes involved in phytohormone biosynthesis and signaling. This study provides new insights regarding the relevance of eukaryotic microalgae as plant growth-promoting agents and helps to build a foundation for future studies regarding the origin and evolution of phytohormone biosynthesis and signaling, as well as other plant colonization and plant growth-promoting mechanisms in soil/plant-associated Micractinium.

Evaluation of the Cutaneous Silent Period in a Healthy Brazilian Population.

PURPOSE: To establish cutaneous silent period (CSP) normative values and investigate the variables that may influence them. METHODS: We tested 41 healthy subjects. All subjects underwent nerve conduction studies, and we evaluated the CSP in both arms. RESULTS: Four subjects did not have CSP and were excluded. The analyses were performed in the healthy group composed of 23 women and 14 men, with a mean age of 35 (range, 19-64) years. The CSP median duration was 23.2 milliseconds (ms), with 2 to 98th percentile at 11.3 and 48.7 ms. The median onset latency was 87.9 (range, 72.9-109) ms, and the median end latency was 112 (range, 93.8-138) ms. The CSP onset latency positively correlated with height, whereas CSP end latency and duration were weakly but significantly associated with age. Some measurements of ulnar nerve conduction study also correlated with CSP measures. The interrater coefficients for the primary measures of onset and end latency demonstrates the reproducibility of the method. CONCLUSIONS: The CSP with the fifth digit stimulation and recording from the abductor digiti minimi muscle is a valid diagnostic tool that can be used in clinical practice.