Guanosine-specific single-stranded ribonuclease effectors of a phytopathogenic fungus potentiate host immune responses.

Plants activate immunity upon recognition of pathogen-associated molecular patterns. Although phytopathogens have evolved a set of effector proteins to counteract plant immunity, some effectors are perceived by hosts and induce immune responses. Here, we show that two secreted ribonuclease effectors, SRN1 and SRN2, encoded in a phytopathogenic fungus, Colletotrichum orbiculare, induce cell death in a signal peptide- and catalytic residue-dependent manner, when transiently expressed in Nicotiana benthamiana. The pervasive presence of SRN genes across Colletotrichum species suggested the conserved roles. Using a transient gene expression system in cucumber (Cucumis sativus), an original host of C. orbiculare, we show that SRN1 and SRN2 potentiate host pattern-triggered immunity responses. Consistent with this, C. orbiculare SRN1 and SRN2 deletion mutants exhibited increased virulence on the host. In vitro analysis revealed that SRN1 specifically cleaves single-stranded RNAs at guanosine, leaving a 3'-end phosphate. Importantly, the potentiation of C. sativus responses by SRN1 and SRN2, present in the apoplast, depends on ribonuclease catalytic residues. We propose that the pathogen-derived apoplastic guanosine-specific single-stranded endoribonucleases lead to immunity potentiation in plants.

Nerve enlargement differs among chronic inflammatory demyelinating polyradiculoneuropathy subtypes and multifocal motor neuropathy.

Objective: We aimed to evaluate differences in ultrasonographic nerve enlargement sites among typical chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), distal CIDP, multifocal CIDP and multifocal motor neuropathy (MMN) in a Japanese population. Methods: We retrospectively reviewed medical records and selected 39 patients (14 with typical CIDP, 7 with multifocal CIDP, 4 with distal CIDP, and 14 with MMN) who underwent ultrasonography. Median and ulnar nerve cross-sectional areas (CSAs) were measured at the wrist, forearm, elbow, and upper arm. CSA ratios for each nerve were calculated as: wrist-to-forearm index (WFI) = wrist CSA/forearm CSA; elbow-to-upper arm index (EUI) = elbow CSA/upper arm CSA; and intranerve CSA variability (INCV) = maximal CSA/minimal CSA. Results: Significant differences were observed among typical CIDP, multifocal CIDP, distal CIDP, and MMN in CSA at the forearm and upper arm in the median nerves (p < 0.05). Patients with multifocal CIDP had lower WFI and EUI and higher INCV than the other groups (p < 0.05). Conclusions: Regardless of the untreated period, compared with other CIDP subtypes and MMN, multifocal CIDP showed a focal and marked nerve enlargement in the Japanese population. Significance: Differences in nerve enlargement site may be an underlying feature of multifocal CIDP.

Selective modification of tryptophan in polypeptides via C-N coupling with azoles using in situ-generated iodine-based oxidants in aqueous media.

This study demonstrates the C-N coupling of tryptophan with azoles, promoted by an in situ-generated iodine-based oxidant. The protocol was successfully applied to the selective modification of tryptophan in nonprotected polypeptide bearing oxidatively sensitive residues in acidic aqueous media. The present method allows the attachment of reactive handles to polypeptides and the peptide stapling.

Functional integration of protein A binding ability to antibody fragments for convenient and tag-free purification.

Although the development of small therapeutic antibodies is important, the affinity tags used for their purification often result in heterogeneous production and immunogenicity. In this study, we integrated Staphylococcus aureus protein A (SpA) binding ability into antibody fragments for convenient and tag-free purification. SpA affinity chromatography is used as a global standard purification method for conventional antibodies owing to its high binding affinity to the Fc region. SpA also has a binding affinity for some variable heavy domains (VH) classified in the VH3 subfamily. Through mutagenesis based on alignment and structural modeling results using the SpA-VH3 cocrystal structure, we integrated the SpA-binding ability into the anti-CD3 single-chain Fv. Furthermore, we applied this mutagenesis approach to more complicated small bispecific antibodies and successfully purified the antibodies using SpA affinity chromatography. The antibodies retained their biological function after purification. Integration of SpA-binding ability into conventional antibody fragments simplifies the purification and monitoring of the production processes and, thus, is an ideal strategy for accelerating the development of small therapeutic antibodies. Furthermore, because of its immunoactivity, the anti-CD3 variable region with SpA-binding ability is an effective building block for developing engineered cancer therapeutic antibodies without the Fc region.

Polyphyllin D induces necroptosis in neuroblastoma cells (IMR-32 and LA-N-2) in mice.

BACKGROUND: We previously reported that polyphyllin D, the main component of the traditional herbal medicinal Paris polyphylla, exhibited anticancer effects in vitro against human neuroblastoma cells. The aim of this investigation was to examine in vivo antitumor effects of polyphyllin D. METHODS: Subcutaneous tumors were established in immune-deficient BALB/c nude mice using human neuroblastoma cell lines IMR-32 and LA-N-2. To evaluate the polyphyllin D activity, we used a mouse model of IMR-32 or LA-N-2 cell lines and analyzed subcutaneous tumors. RESULTS: Subcutaneous tumor models were successfully established in mice using two human neuroblastoma cell lines. In the subcutaneous tumor model, porphyrin D was found to suppress tumor volume. We found that polyphyllin D suppressed the number of foci by Ki-67 staining (IMR-32 and LA-N-2; p < 0.01, 0.02, respectively). We found that polyphyllin D induces the RIPK3 expression, while polyphyllin D phosphorylates Ser358 in IMR-32 and Ser358 and Tyr376 in LA-N-2. CONCLUSION: We developed a mouse model of subcutaneous tumors of neuroblastoma and demonstrated for the first time that polyphyllin D has an antitumor effect on neuroblastoma. Polyphyllin D can cause necroptosis depending on the cell type. The new drug can be expected by investigating a method to selectively induce cell death through the analysis of necroptosis.

A Fluorescence Cross-Correlation-Spectroscopy-Based Immunoassay for Rapid, Selective, and Accurate Protein Sizing in Human Plasma, Applied to the von Willebrand Factor.

Multimeric abnormalities in plasma von Willebrand factor (VWF) cause bleeding or clotting disorders. Electrophoretic analysis of multimers is used to detect such abnormalities but is qualitative, slow, and difficult to standardize. Fluorescence correlation spectroscopy (FCS) is a good alternative but is affected by low selectivity and concentration bias. Here, we report the development of a homogeneous immunoassay based on dual-color fluorescence cross-correlation spectroscopy (FCCS) that overcomes these challenges. By performing a mild denaturation treatment followed by reacting with polyclonal antibodies, the concentration bias was drastically reduced. The use of a dual antibody assay improved selectivity. Diffusion times of immunolabeled VWF were measured with FCCS and standardized relative to calibrator measurements. The assay measures size changes in VWF using 1 µL of plasma and less than 10 ng of antibody per measurement and was validated over a 16-fold range of VWF antigen concentration (VWF:Ag), with a sensitivity of VWF:Ag 0.8%. Concentration bias and imprecision were less than 10%. Measurements were unaffected by hemolytic, icteric, or lipemic interference. Strong correlations were obtained with reference densitometric readouts (0.97 for calibrators, 0.85 for clinical samples), and significant differences were found between normal (n = 10), type 2A (n = 5), and type 2B (n = 5) von Willebrand's disease and acquired thrombotic thrombocytopenic purpura (n = 10) samples (p < 0.01). This FCCS based immunoassay accurately and selectively determines changes in the multimeric status of plasma VWF and may be used as a simpler, faster, and a standardizable alternative for multimer analysis, following further clinical validation in larger cohorts.

Development of a new HISCL automated CXCL9 immunoassay.

C-X-C motif chemokine ligand 9 (CXCL9), a candidate biomarker, reflects type 1 (T1) inflammation pathology. Here, we report the analytical performance and clinical characteristics of a new CXCL9 reagent for a fully automated immunoassay device. We evaluated the limits of blank, detection, and quantitation (LoQ) along with other efficacy parameters, and the ability of the assay to report patient health, COVID-19 status, and the presence of asthma and/or interstitial lung diseases (ILDs). The coefficient of variation for 5-day total precision using two instruments was 7% across two controls, serum, and plasma panels. LoQ of 2.2 pg/mL suggested the efficacy of the assay in detecting T1 inflammation in plasma or serum; no cross-reactivity or interference was observed. We identified high serum CXCL9 levels in samples from patients with acute COVID-19 infections (n = 57), chronic bird-related hypersensitivity pneumonitis (n = 61), asthma (n = 194), and ILDs (n = 84) compared to healthy individuals (< 39.0 pg/mL). Furthermore, CXCL9 levels increased with age in asthma patients, and an opposite trend was observed for T2 inflammatory factors. These results suggest the utility of the automated CXCL9 immunoassay for measuring CXCL9 in clinical samples and reflect its role in T1 inflammation.

Structural metamorphosis and photophysical properties of thermostable nano- and microcrystalline lanthanide polymer with flexible coordination chains.

Luminescent lanthanide coordination polymer crystals (LCPCs) represent an area of growing interest in materials chemistry owing to their unique and tailorable functional properties. The LCPCs provide a high level of structural tunability, including size- and morphology-dependent properties; therefore, they are promising materials for next-generation phosphors in a wide range of applications such as light emitting diodes. Here, by controlling the morphology of thermostable europium coordination polymer crystals, [Eu(hfa)3(dpbp)]n, hfa: hexafluoroacetylacetonate and dpbp:4,4'-bis(diphenyl　phosphoryl) biphenyl), we realized a novel red phosphor with narrow linewidth emission (FWHM = 7.8 nm). The obtained luminescent LCPCs with unique structures were characterized by X-ray diffraction (XRD), scanning transmission electron microscopy (STEM), dynamic light scattering (DLS) and thermogravimetric analysis. Among, them, size tunable crystalline polymer spheres were found to have high internal quantum efficiency (ex., IQE = 79%) and highly thermostability (>300°C), and to exhibit dispersibility in PMMA media. The obtained results on the structural tunability of these materials can be used for the development of synthesis techniques for nanoscale materials based on crystalline lanthanide-based coordination phosphors.

[A case of autopsy-confirmed duodenal perforation due to calcium polystyrene sulfonate].

A 77-year-old male patient was referred to our hospital because of jaundice. He was diagnosed with alcoholic liver cirrhosis and was admitted to our hospital because of liver failure. After admission, we observed conservative liver disease, but the liver damage did not improve and gradually worsened. Renal function deteriorated during liver failure. Hyperkalemia presented due to renal dysfunction. Hence, calcium polystyrene sulfonate (CPS) was initiated. He died because of liver failure although hyperkalemia improved. An autopsy revealed ulcer perforation with CPS crystals in the duodenum. A basic substance considered a crystal of CPS was found by hematoxylin and eosin staining from the ulcer adjacent to the perforation and the exudate attached to the peritoneum. Furthermore, a large amount of CPS crystals were found in the ascites. A final diagnosis of gastrointestinal perforation peritonitis due to CPS was made. Gastrointestinal perforation due to CPS is presumed as a direct mucosal injury due to the drug, most of which is the sigmoid colon of elderly patients. Upper gastrointestinal tract perforation is extremely rare. We experienced a case of autopsy in which duodenal perforation due to CPS was pathologically confirmed. CPS is a widely used drug for renal disorders, but it has a risk of gastrointestinal injury. Therefore, a potential gastrointestinal mucosal injury should be considered when using CPS.

Iron Nutrition in Plants: Towards a New Paradigm?

Iron (Fe) is an essential micronutrient for plant growth and development. Fe availability affects crops' productivity and the quality of their derived products and thus human nutrition. Fe is poorly available for plant use since it is mostly present in soils in the form of insoluble oxides/hydroxides, especially at neutral to alkaline pH. How plants cope with low-Fe conditions and acquire Fe from soil has been investigated for decades. Pioneering work highlighted that plants have evolved two different strategies to mine Fe from soils, the so-called Strategy I (Fe reduction strategy) and Strategy II (Fe chelation strategy). Strategy I is employed by non-grass species whereas graminaceous plants utilize Strategy II. Recently, it has emerged that these two strategies are not fully exclusive and that the mechanism used by plants for Fe uptake is directly shaped by the characteristics of the soil on which they grow (e.g., pH, oxygen concentration). In this review, recent findings on plant Fe uptake and the regulation of this process will be summarized and their impact on our understanding of plant Fe nutrition will be discussed.

Successful treatment of mediastinal pancreatic pseudocyst and pancreatic pleural effusion with endoscopic pancreatic duct drainage: A case report.

An 81-year-old man with chronic pancreatitis was being treated with a protease inhibitor. He developed an acute exacerbation of chronic pancreatitis and dyspnea. Contrast-enhanced computed tomography showed disruption of the main pancreatic duct, a cystic lesion connecting the mediastinum to the main pancreatic duct, and left pleural effusion. We diagnosed a pancreatic pseudocyst, mediastinal pancreatic pseudocyst, and pancreatic pleural effusion. Endoscopic retrograde pancreatography showed leakage of contrast medium from the pancreatic body; furthermore, a cystic cavity extending to the mediastinum through a pancreatic duct fistula was visualized. An endoscopic transpapillary nasopancreatic drainage tube was placed in the cystic cavity. Computed tomography showed that the mediastinal pseudocyst and pleural effusion had disappeared. Endoscopic transpapillary pancreatic duct drainage may be useful when a connection between the main pancreatic duct and a mediastinal pseudocyst is confirmed by imaging.

A Prospective Study of Neoadjuvant Gemcitabine Plus Nab-paclitaxel in Patients with Borderline-resectable Pancreatic Cancer.

Objectives Neoadjuvant therapy followed by radical resection improves the borderline-resectable pancreatic cancer (BRPC) prognosis; however, the optimal therapeutic regimen remains unclear. Gemcitabine plus nab-paclitaxel (GnP) showed a high anti-tumor effect in primary lesions in a prospective study for metastatic disease. However, evidence concerning its feasibility is still lacking in patients with BRPC. We therefore evaluated the tolerability of neoadjuvant GnP (NAC-GnP) for BRPC. Methods This single-center prospective study evaluated 10 patients with BRPC who were treated with two cycles of NAC-GnP. The primary endpoint was feasibility for NAC-GnP. Treatment feasibility was defined as a successful outcome in at least eight patients. Results Ten patients who had BRPC in contact with the celiac artery (n=5), superior mesenteric artery (n=3), or hepatic artery (n=2) were enrolled. The median age was 75 (range, 40-82) years old. Grade 3 anorexia and grade 2 pneumonia occurred in one patient each, so treatment was feasible in eight patients. The median primary tumor reduction and response rates were 33% (range, 0-68%) and 60%, respectively. Six of eight patients who had abnormal CA19-9 levels at the time of enrolment showed a decrease in CA19-9 levels, with a median decrease of 72%. Five patients underwent radical resection, including R0 resection in four. Postoperative grade IIIa Clavien-Dindo complications occurred in one patient (upper gastrointestinal bleeding and pancreatic fistula). Conclusion Two-cycle NAC-GnP is a feasible treatment for patients with BRPC. Further studies on NAC-GnP in patients with BRPC are warranted.

Evaluation of Ki-67 as prognostic factor for pediatric neuroblastoma and the possibility of molecular-targeted drugs with VEGF and PDGFR.

BACKGROUND: Neuroblastoma (NB) is a pediatric malignant solid tumor characterized as refractory cancer with poor prognosis. The Mitosis-Karyorrhexis Index (MKI) is a prognostic factor but is prone to observer bias. The usefulness of MKI with Ki-67, as a marker of malignancy, was investigated. The efficacy of molecular-targeted therapeutic agents with fewer side effects in tumors has been studied. Molecular-targeted therapy targets include vascular endothelial growth factor (VEGF), involved in tumor angiogenesis; c-Kit, receptor of Kit/stem cells involved in tumor growth, vasculature, and lymphangiogenesis; platelet-derived growth factor receptor (PDGFR); and B-Raf proto-oncogene, serine/threonine kinase (BRAF), involved in the RAS protein-mediated mitogen-activated protein kinase pathway. Therefore, expression profiles of these factors and growth inhibitory effects of molecular-targeted drugs against NB were investigated. METHODS: Ten frozen NB tissue samples collected from January 1993 to December 2017 were evaluated immunohistochemically for Ki-67 and VEGF. c-Kit, PDGFR, and BRAF expression levels were evaluated using enzyme-linked immunosorbent assays; relationships between these factors and clinicopathological parameters of NB were analyzed. RESULTS: Eight patients with NB showed no amplification of MYCN (MYCN proto-oncogene, bHLH transcription factor). There were two cases of ganglioneuroblastoma (GNB). More NB cells were positive for Ki-67 than for GNB cells. VEGF expression was observed in all NB specimens and was stronger in stage IIB and higher. No BRAF or c-Kit activity was observed; PDGFR activity was greater in NB than in GNB (P=0.02). CONCLUSIONS: Thus, Ki-67 may help evaluate NB malignancy. As the first therapy for NB prevents amplification of MYCN, agents targeting PDGFR as well as VGFG can inhibit NB cell proliferation.

Ethanol-Mediated Novel Survival Strategy against Drought Stress in Plants.

Water scarcity is a serious agricultural problem causing significant losses to crop yield and product quality. The development of technologies to mitigate the damage caused by drought stress is essential for ensuring a sustainable food supply for the increasing global population. We herein report that the exogenous application of ethanol, an inexpensive and environmentally friendly chemical, significantly enhances drought tolerance in Arabidopsis thaliana, rice and wheat. The transcriptomic analyses of ethanol-treated plants revealed the upregulation of genes related to sucrose and starch metabolism, phenylpropanoids and glucosinolate biosynthesis, while metabolomic analysis showed an increased accumulation of sugars, glucosinolates and drought-tolerance-related amino acids. The phenotyping analysis indicated that drought-induced water loss was delayed in the ethanol-treated plants. Furthermore, ethanol treatment induced stomatal closure, resulting in decreased transpiration rate and increased leaf water contents under drought stress conditions. The ethanol treatment did not enhance drought tolerance in the mutant of ABI1, a negative regulator of abscisic acid (ABA) signaling in Arabidopsis, indicating that ABA signaling contributes to ethanol-mediated drought tolerance. The nuclear magnetic resonance analysis using 13C-labeled ethanol indicated that gluconeogenesis is involved in the accumulation of sugars. The ethanol treatment did not enhance the drought tolerance in the aldehyde dehydrogenase (aldh) triple mutant (aldh2b4/aldh2b7/aldh2c4). These results show that ABA signaling and acetic acid biosynthesis are involved in ethanol-mediated drought tolerance and that chemical priming through ethanol application regulates sugar accumulation and gluconeogenesis, leading to enhanced drought tolerance and sustained plant growth. These findings highlight a new survival strategy for increasing crop production under water-limited conditions.

Arabidopsis NPF5.1 regulates ABA homeostasis and seed germination by mediating ABA uptake into the seed coat.

Abscisic acid (ABA) is a plant hormone that induces seed dormancy during seed development and inhibits seed germination after imbibition. Although ABA is synthesized in the seed coat (testa), endosperm, and embryo, the physiological roles of the hormone derived from each tissue are not fully understood. We found that the gene encoding an Arabidopsis ABA importer, NPF5.1, was expressed in the seed coat during seed development. Dry seeds of loss-of-function npf5.1 mutants contained significantly higher levels of dihydrophaseic acid (DPA), an inactive ABA metabolite, than the wild type. The npf5.1 mutant also had a slight increase in ABA content. An increase in DPA was prominent in the fraction containing the seed coat and endosperm. Seed germination of the npf5.1 mutant was similar to the wild type in the presence of ABA or the gibberellin biosynthesis inhibitor paclobutrazol. However, a mutation in NPF5.1 suppressed the paclobutrazol-resistant germination of npf4.6, a mutant impaired in an ABA importer expressed in the embryo. These results suggest that ABA uptake into the seed coat mediated by NPF5.1 is important for ABA homeostasis during seed development and for regulating seed germination.

Fully automated and highly specific plasma ß-amyloid immunoassays predict ß-amyloid status defined by amyloid positron emission tomography with high accuracy.

BACKGROUND: Clinicians, researchers, and patients alike would greatly benefit from more accessible and inexpensive biomarkers for neural ß-amyloid (Aß). We aimed to assess the performance of fully automated plasma Aß immunoassays, which correlate significantly with immunoprecipitation mass spectrometry assays, in predicting brain Aß status as determined by visual read assessment of amyloid positron emission tomography (PET). METHODS: The plasma Aß42/Aß40 ratio was measured using a fully automated immunoassay platform (HISCL series) in two clinical studies (discovery and validation studies). The discovery and validation sample sets were retrospectively and randomly selected from participants with early Alzheimer's disease (AD) identified during screening for the elenbecestat Phase 3 program. RESULTS: We included 197 participants in the discovery study (mean [SD] age 71.1 [8.5] years; 112 females) and 200 in the validation study (age 70.8 [7.9] years; 99 females). The plasma Aß42/Aß40 ratio predicted amyloid PET visual read status with areas under the receiver operating characteristic curves of 0.941 (95% confidence interval [CI] 0.910-0.973) and 0.868 (95% CI 0.816-0.920) in the discovery and validation studies, respectively. In the discovery study, a cutoff value of 0.102 was determined based on maximizing the Youden Index, and the sensitivity and specificity were calculated to be 96.0% (95% CI 90.1-98.9%) and 83.5% (95% CI 74.6-90.3%), respectively. Using the same cutoff value, the sensitivity and specificity in the validation study were calculated to be 88.0% (95% CI 80.0-93.6%) and 72.0% (95% CI 62.1-80.5%), respectively. CONCLUSIONS: The plasma Aß42/Aß40 ratio measured using the HISCL series achieved high accuracy in predicting amyloid PET status. Since our blood-based immunoassay system is less invasive and more accessible than amyloid PET and cerebrospinal fluid testing, it may contribute to the diagnosis of AD in routine clinical practice.

Antitumor effect of polyphyllin D on liver metastases of neuroblastoma.

PURPOSE: We previously reported that polyphyllin D, a main component of the traditional Chinese medicinal herb Paris polyphylla, exhibited anticancer effects in vitro against human neuroblastoma cells. The aims of this investigation was to examine the presence or absence of in vivo anti-metastasis effects of polyphyllin D were to establish a liver metastasis model of neuroblastoma and to evaluate the anti-metastasis effects of polyphyllin D. METHODS: Subcutaneous and intraperitoneal tumors, and metastasis models were established in immune-deficient BALB/c nude and BALB/c Rag-2/Jak3 double-deficient (BRJ) mice using the human neuroblastoma cell lines IMR-32, LA-N-2, or NB-69. For evaluating polyphyllin D activity, we used a mouse model of liver metastasis with the IMR-32 cells line injected through the tail vein. We analyzed the livers number and area of liver tumors in of the phosphate buffer solution- and polyphyllin D-treated groups. RESULTS: Liver metastasis and intraperitoneal dissemination models were successfully established in immune-deficient BRJ mice using the three human neuroblastoma cell lines. In the liver metastasis, the model of IMR-32 cells, we found that polyphyllin D suppressed both the number and total area of metastatic foci the average number of metastatic foci, average focus areas, and number of cleaved caspase-3-positive cells were significantly lower in the polyphyllin D group (p = 0.016, 0.020, 0.043, respectively). CONCLUSIONS: We developed a mouse models of neuroblastoma metastasis and demonstrated for the first time that polyphyllin D has an antitumor effect on neuroblastoma liver metastases.

4-Phenylbutyric acid promotes plant regeneration as an auxin by being converted to phenylacetic acid via an IBR3-independent pathway.

4-Phenylbutyric acid (4PBA) is utilized as a drug to treat urea cycle disorders and is also being studied as a potential anticancer drug that acts via its histone deacetylase (HDAC) inhibitor activity. During a search to find small molecules that affect plant regeneration in Arabidopsis, we found that 4PBA treatment promotes this process by mimicking the effect of exogenous auxin. Specifically, plant tissue culture experiments revealed that a medium containing 4PBA enhances callus formation and subsequent shoot regeneration. Analyses with auxin-responsive or cytokinin-responsive marker lines demonstrated that 4PBA specifically enhances AUXIN RESPONSE FACTOR (ARF)-dependent auxin responses. Our western blot analyses showed that 4PBA treatment does not enhance histone acetylation in Arabidopsis, in contrast to butyric acid and trichostatin A, other chemicals often used as HDAC inhibitors, suggesting this mechanism of action does not explain the observed effect of 4PBA on regeneration. Finally, mass spectroscopic analysis and genetic approaches uncovered that 4PBA in Arabidopsis plants is converted to phenylacetic acid (PAA), a known natural auxin, in a manner independent of peroxisomal IBR3-related ß-oxidation. This study demonstrates that 4PBA application promotes regeneration in explants via its auxin activity and has potential applications to not only plant tissue culture engineering but also research on the plant ß-oxidation pathway.

Clinical Utility of Repetitive Nerve Stimulation Test in Differentiating Multifocal Motor Neuropathy From Progressive Muscular Atrophy.

OBJECTIVES: To evaluate the utility of repetitive nerve stimulation test (RNS) for differentiating multifocal motor neuropathy (MMN) and progressive muscular atrophy (PMA). METHODS: We retrospectively enrolled 20 patients with MMN or PMA. We extracted the results of the initial 3-Hz RNS in the ulnar and accessory nerves and compared the percentage and frequency of abnormal decremental responses between both groups. RESULTS: RNS was performed in 8 ulnar and 9 accessory nerves in patients with MMN, and in 8 ulnar and 10 accessory nerves in patients with PMA. Patients with MMN had a significantly lower decrement percentage (0.6 ± 4.0% in MMN vs. 10.3 ± 6.5% in PMA, P < 0.01) and frequency of abnormal decremental response (0 of 9 in MMN vs. 6 of 10 in PMA, P = 0.01) than patients with PMA in the accessory nerve. CONCLUSIONS: The RNS has clinical utility for differentiating MMN from PMA.