Ultrasound-Guided Perineural Vitamin B12 Injection for Brachial Plexus Injury: A Preliminary Study.

Individuals with brachial plexus injury (BPI) require upper limb function restoration, but the treatment remains controversial. Vitamin B12 may aid in pain control and nerve regeneration. We present the technical aspects of ultrasound-guided perineural vitamin B12 injection for BPI. The demonstrative case is a 50-year-old man with BPI resulting from a traffic accident. Under ultrasound guidance, vitamin B12 was injected precisely into the brachial plexus compartment around the swollen neuroma of the C6 root. Motor and sensory functions of the left upper extremity improved over 6 months. Ultrasound-guided perineural vitamin B12 injection may be an efficient and personalized intervention in cases of post-ganglionic BPI that failed to improve in the first 3 months.

The clinicopathological and genetic differences among gastric cancer patients with no recurrence, early recurrence, and late recurrence after curative surgery.

BACKGROUND: To date, few reports have investigated the genetic alterations and clinicopathological features among gastric cancer (GC) patients with no tumor recurrence, early recurrence, and late recurrence following curative surgery. METHODS: A total of 473 GC patients undergoing curative surgery were included. The clinicopathological characteristics, patient prognosis, recurrence patterns, and genetic alterations were compared between GC patients with early recurrence and late recurrence. RESULTS: Among the 473 GC patients, 119 had early recurrence (<2 years) and 45 had late recurrence (≥2 years). Patients with early recurrence had tumor size larger than 5 cm, fewer superficial-type tumors, more lymphovascular invasion, more advanced pathological T and N categories and Tumor, Node, Metastasis (TNM) stages, and worse 5-year overall survival than patients with late recurrence and no recurrence. For intestinal-type GC, patients with no tumor recurrence had more Helicobacter pylori infection than patients with early recurrence and late recurrence; for diffuse-type GC patients, the frequency of PIK3CA amplification was the highest in early recurrence, followed by late recurrence and no recurrence. GC patients with single-site recurrence had more ARID1A mutations than those with multiple-site recurrence. Multivariate analysis demonstrated that age, tumor recurrence, and pathological N categories were independent prognostic factors. CONCLUSION: PIK3CA amplifications were more common in diffuse-type GC with early recurrence, whereas ARID1A mutations were more common in patients with single-site recurrence. Targeted therapy and immunotherapy might be helpful for these patients.

Compensation for Electrode Detachment in Electrical Impedance Tomography with Wearable Textile Electrodes.

Electrical impedance tomography (EIT) is a radiation-free and noninvasive medical image reconstruction technique in which a current is injected and the reflected voltage is received through electrodes. EIT electrodes require good connection with the skin for data acquisition and image reconstruction. However, detached electrodes are a common occurrence and cause measurement errors in EIT clinical applications. To address these issues, in this study, we proposed a method for detecting faulty electrodes using the differential voltage value of the detached electrode in an EIT system. Additionally, we proposed the voltage-replace and voltage-shift methods to compensate for invalid data from the faulty electrodes. In this study, we present the simulation, experimental, and in vivo chest results of our proposed methods to verify and evaluate the feasibility of this approach.

Rapid Detection of Virus Nucleic Acid via Isothermal Amplification on Plasmonic Enhanced Digitizing Biosensor.

Rapid detection for infectious diseases is highly demanded in diagnosis and infection prevention. In this work, we introduced a plasmonic enhanced digitizing biosensor for the rapid detection of nucleic acids. The sensor successfully achieved the detection of loop-mediated isothermal amplification for the hepatitis virus in this work. The sensor comprised a nanodisc array and Bst polymerases conjugated on the rough surface of a nanodisc. The rough surface of the nanodisc provided plasmonic hot spots to enhance the fluorescence signal. The virus DNA was detected by conducting a modified loop-mediated isothermal amplification with fluorescence resonance energy transfer reporter conjugated primers on the sensor. The modified isothermal amplification improved the signal contrast and detection time compared to the original assay. By integrating the modified amplification assay and plasmonic enhancement sensor, we achieved rapid detection of the hepatitis virus. Nucleic acid with a concentration of 10-3 to 10-4 mg/mL was detected within a few minutes by our design. Our digitizing plasmonic nanoarray biosensor also showed 20-30 min earlier detection compared to conventional loop-mediated isothermal amplification sensors.

Dry Wearable Textile Electrodes for Portable Electrical Impedance Tomography.

Electrical impedance tomography (EIT), a noninvasive and radiation-free medical imaging technique, has been used for continuous real-time regional lung aeration. However, adhesive electrodes could cause discomfort and increase the risk of skin injury during prolonged measurement. Additionally, the conductive gel between the electrodes and skin could evaporate in long-term usage and deteriorate the signal quality. To address these issues, in this work, textile electrodes integrated with a clothing belt are proposed to achieve EIT lung imaging along with a custom portable EIT system. The simulation and experimental results have verified the validity of the proposed portable EIT system. Furthermore, the imaging results of using the proposed textile electrodes were compared with commercial electrocardiogram electrodes to evaluate their performance.

Multi-Layer Reflectivity Calculation Based Meta-Modeling of the Phase Mapping Function for Highly Reproducible Surface Plasmon Resonance Biosensing.

Phase-sensitive surface plasmon resonance biosensors are known for their high sensitivity. One of the technology bottle-necks of such sensors is that the phase sensorgram, when measured at fixed angle set-up, can lead to low reproducibility as the signal conveys multiple data. Leveraging the sensitivity, while securing satisfying reproducibility, is therefore is an underdiscussed key issue. One potential solution is to map the phase sensorgram into refractive index unit by the use of sensor calibration data, via a simple non-linear fit. However, basic fitting functions poorly portray the asymmetric phase curve. On the other hand, multi-layer reflectivity calculation based on the Fresnel coefficient can be employed for a precise mapping function. This numerical approach however lacks the explicit mathematical formulation to be used in an optimization process. To this end, we aim to provide a first methodology for the issue, where mapping functions are constructed from Bayesian optimized multi-layer model of the experimental data. The challenge of using multi-layer model as optimization trial function is addressed by meta-modeling via segmented polynomial approximation. A visualization approach is proposed for assessment of the goodness-of-the-fit on the optimized model. Using metastatic cancer exosome sensing, we demonstrate how the present work paves the way toward better plasmonic sensors.

Biosensing Amplification by Hybridization Chain Reaction on Phase-Sensitive Surface Plasmon Resonance.

Surface Plasmon Resonance (SPR) is widely used in biological and chemical sensing with fascinating properties. However, the application of SPR to detect trace targets is hampered by non-specific binding and poor signal. A variety of approaches for amplification have been explored to overcome this deficiency including DNA aptamers as versatile target detection tools. Hybridization chain reaction (HCR) is a high-efficiency enzyme-free DNA amplification method operated at room temperature, in which two stable species of DNA hairpins coexist in solution until the introduction of the initiator strand triggers a cascade of hybridization events. At an optimal salt condition, as the concentrations of H1 and H2 increased, the HCR signals were enhanced, leading to signal amplification reaching up to 6.5-fold of the detection measure at 30 min. This feature enables DNA to act as an amplifying transducer for biosensing applications to provide an enzyme-free alternative that can easily detect complex DNA sequences. Improvement of more diverse recognition events can be achieved by integrating HCR with a phase-sensitive SPR (pSPR)-tested aptamer stimulus. This work seeks to establish pSPR aptamer system for highly informative sensing by means of an amplification HCR. Thus, combining pSPR and HCR technologies provide an expandable platform for sensitive biosensing.

Breathing Sound Segmentation and Detection Using Transfer Learning Techniques on an Attention-Based Encoder-Decoder Architecture.

This paper focuses on the use of an attention-based encoder-decoder model for the task of breathing sound segmentation and detection. This study aims to accurately segment the inspiration and expiration of patients with pulmonary diseases using the proposed model. Spectrograms of the lung sound signals and labels for every time segment were used to train the model. The model would first encode the spectrogram and then detect inspiratory or expiratory sounds using the encoded image on an attention-based decoder. Physicians would be able to make a more precise diagnosis based on the more interpretable outputs with the assistance of the attention mechanism.The respiratory sounds used for training and testing were recorded from 22 participants using digital stethoscopes or anti-noising microphone sets. Experimental results showed a high 92.006% accuracy when applied 0.5 second time segments and ResNet101 as encoder. Consistent performance of the proposed method can be observed from ten-fold cross-validation experiments.

Hybridization Chain Reactions Targeting the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).

In this work, hybridization chain reactions (HCRs) toward Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) nucleocapsid phosphoproteins gene loci and human RNase P are proposed to provide an isothermal amplification screening tool. The proposed chain reactions target the complementary DNA (cDNA) of SARS-CoV-2, with loci corresponding to gold-standard polymerase chain reaction (PCR) loci. Four hybridization chain reaction reactions are demonstrated herein, targeting N1/N2/N3 loci and human RNase P. The design of the hybridization chain reaction, herein, is assisted with an algorithm. The algorithm helps to search target sequences with low local secondary structure and high hybridization efficiency. The loop domain of the fuel hairpin molecule H1 and H2, which are the tunable segments in such reactions, are used as an optimization parameter to improve the hybridization efficiency of the chain reaction. The algorithm-derived HCR reactions were validated with gel electrophoresis. All proposed reactions exhibit a hybridization complex with a molecular mass >1.5k base pairs, which is clear evidence of chain reaction. The hybridization efficiency trend revealed by gel electrophoresis corresponds nicely to the simulated data from the algorithm. The HCR reactions and the corresponding algorithm serve as a basis to further SARS-CoV-2 sensing applications and facilitate better screening strategies for the prevention of on-going pandemics.

Gold Nanoparticle-Based Colorimetric Strategies for Chemical and Biological Sensing Applications.

Gold nanoparticles are popularly used in biological and chemical sensors and their applications owing to their fascinating chemical, optical, and catalytic properties. Particularly, the use of gold nanoparticles is widespread in colorimetric assays because of their simple, cost-effective fabrication, and ease of use. More importantly, the gold nanoparticle sensor response is a visual change in color, which allows easy interpretation of results. Therefore, many studies of gold nanoparticle-based colorimetric methods have been reported, and some review articles published over the past years. Most reviews focus exclusively on a single gold nanoparticle-based colorimetric technique for one analyte of interest. In this review, we focus on the current developments in different colorimetric assay designs for the sensing of various chemical and biological samples. We summarize and classify the sensing strategies and mechanism analyses of gold nanoparticle-based detection. Additionally, typical examples of recently developed gold nanoparticle-based colorimetric methods and their applications in the detection of various analytes are presented and discussed comprehensively.

Reversible Spasticity Suppression and Locomotion Change After Pulsed Radiofrequency on the Dorsal Root Ganglia of Rats With Spinal Cord Injury.

OBJECTIVES: Radiofrequency has been used to suppress spasticity affecting motion in patients with cerebral palsy and spinal cord injury. This study tested spasticity suppression and locomotion change after pulsed radiofrequency (PRF) at the dorsal root ganglion of rats with spasticity. MATERIALS AND METHODS: Twenty-four rats that survived for 28 days after thoracic spinal cord injury and showed spasticity in the right hind limb were separated randomly to a PRF group or Sham operation group. PRF consisted of 2 Hz biphasic 25 msec trains of PRF (500 kHz, 5 V intensity) applied on the right L5 dorsal root ganglion for 300 sec. Muscle tension of the right triceps surae was measured at 450 deg/sec of passive ankle dorsiflexion on the day before and 3, 7, and 14 days after PRF or sham operation. Locomotive function was evaluated by obtaining Basso, Beattie, and Bresnahan (BBB) scores. RESULTS: Muscle tension of the triceps surae decreased significantly three days after PRF, and gradually returned to baseline 14 days later. In the sham operation group, muscle tension increased significantly more than 14 days. The BBB scores declined from 10 to 8 after PRF and returned to pre-PRF levels 14 days later, while scores remained constant after sham operation. CONCLUSIONS: PRF produced significant and reversible suppression in spasticity, but this was accompanied by deterioration in locomotive function. Thus, caution should be exercised in considering the benefits and costs in suppressing spasticity in ambulatory patients, and implanted devices that apply titratable doses of PRF may be best to optimize patients' needs.

Low-Fouling Characteristics of Ultrathin Zwitterionic Cysteine SAMs.

Surface fouling remains an exigent issue for many biological implants. Unwanted solutes adsorb to reduce device efficiency and hasten degradation while increasing the risks of microbial colonization and adverse inflammatory response. To address unwanted fouling in modern implants in vivo, surface modification with antifouling polymers has become indispensable. Recently, zwitterionic self-assembled monolayers, which contain two or more charged functional groups but are electrostatically neutral and form highly hydrated surfaces, have been the focus of many antifouling coatings. Reports using various compositions of zwitterionic polymer brushes have demonstrated ultralow fouling in the ng/cm2 range. These coatings, however, are thick and can hinder the target application of biological devices. Here, we report an ultrathin (8.52 Å) antifouling self-assembled monolayer composed of cysteine that is amenable to facile fabrication. The antifouling characteristics of the zwitterionic surfaces were evaluated against bovine serum albumin, fibrinogen, and human blood in real time using quartz crystal microbalance and surface plasmon resonance imaging. Compared to untreated gold surfaces, the ultrathin cysteine coating reduced the adsorption of bovine serum albumin by 95% (43 ng/cm2 adsorbed) after 3 h and 90% reduction after 24 h. Similarly, the cysteine self-assembled monolayer reduced the adsorption of fibrinogen as well as human blood by >90%. The surfaces were further characterized using scanning electron microscopy: protein-enhanced adsorption and cellular adsorption in human blood was found on untreated surfaces but not on the cysteine SAM-protected surfaces. These findings suggest that surfaces can be functionalized with an ultrathin layer of cysteine to resist the adsorption of key proteins, with performance comparable to zwitterionic polymer brushes. As such, cysteine surface coatings are a promising methodology to improve the long-term utility of biological devices.

Demographic and Symptomatic Features of Voice Disorders and Their Potential Application in Classification Using Machine Learning Algorithms.

BACKGROUND: Studies have used questionnaires of dysphonic symptoms to screen voice disorders. This study investigated whether the differential presentation of demographic and symptomatic features can be applied to computerized classification. METHODS: We recruited 100 patients with glottic neoplasm, 508 with phonotraumatic lesions, and 153 with unilateral vocal palsy. Statistical analyses revealed significantly different distributions of demographic and symptomatic variables. Machine learning algorithms, including decision tree, linear discriminant analysis, K-nearest neighbors, support vector machine, and artificial neural network, were applied to classify voice disorders. RESULTS: The results showed that demographic features were more effective for detecting neoplastic and phonotraumatic lesions, whereas symptoms were useful for detecting vocal palsy. When combining demographic and symptomatic variables, the artificial neural network achieved the highest accuracy of 83 ± 1.58%, whereas the accuracy achieved by other algorithms ranged from 74 to 82.6%. Decision tree analyses revealed that sex, age, smoking status, sudden onset of dysphonia, and 10-item voice handicap index scores were significant characteristics for classification. CONCLUSION: This study demonstrated a significant difference in demographic and symptomatic features between glottic neoplasm, phonotraumatic lesions, and vocal palsy. These features may facilitate automatic classification of voice disorders through machine learning algorithms.

Reversion of gold nanoparticle aggregates for the detection of Cu2+ and its application in immunoassays.

A high concentration of copper is a hazardous element to organisms and human health. Although various strategies have been reported for the sensitive detection of copper, a facile and rapid detection of aqueous copper has seldom been addressed to date. Here, we present an easy and accessible colorimetric method to detect Cu2+ using the redispersion of cysteamine-modified gold nanoparticles (CA-AuNPs). Initially, CA caused the aggregation of AuNPs due to the electrostatic interaction and aggregated AuNPs can be regenerated in basic medium. The subsequent addition of Cu2+ to the CA-AuNP dispersion could effectively trigger the aggregation of CA-AuNPs, resulting from the coordination reactivity between the deprotonated CA and Cu2+. This strategy resulted in a detection limit (LOD) of 1.52 µM in drinking water, which is below the U.S. Environmental Protection Agency permissible limit (20 µM). To demonstrate the broad application of CA-AuNPs, we further applied this method to plasmonic immunoassays based on the competitive interaction of Cu2+ between CA-AuNPs and enzymes. The LOD of the Down syndrome biomarker hyperglycosylated human chorionic gonadotropin (H-hCG) was 0.125 mIU mL-1, which is better than that of commercial immunoassays. Importantly, the determination of H-hCG in serum indicates its applicability for the measurement of real samples. Our assay agrees well with the current immunoassay systems and thus it can easily be expanded to a more common sensing platform for different types of biotargets by changing the corresponding antibodies.

Current Perspectives on Viable but Non-culturable State in Foodborne Pathogens.

The viable but non-culturable (VBNC) state, a unique state in which a number of bacteria respond to adverse circumstances, was first discovered in 1982. Unfortunately, it has been reported that many foodborne pathogens can be induced to enter the VBNC state by the limiting environmental conditions during food processing and preservation, such as extreme temperatures, drying, irradiation, pulsed electric field, and high pressure stress, as well as the addition of preservatives and disinfectants. After entering the VBNC state, foodborne pathogens will introduce a serious crisis to food safety and public health because they cannot be detected using conventional plate counting techniques. This review provides an overview of the various features of the VBNC state, including the biological characteristics, induction and resuscitation factors, formation and resuscitation mechanisms, detection methods, and relationship to food safety.

Rapid and Delayed Effects of Pulsed Radiofrequency on Neuropathic Pain: Electrophysiological, Molecular, and Behavioral Evidence Supporting Long-Term Depression.

BACKGROUND: Pulsed radiofrequency (PRF) has been widely employed for ameliorating clinical neuropathic pain. How PRF alters electrophysiological transmission and modulates biomolecular functions in neural tissues has yet to be clarified. We previously demonstrated that an early application of low-voltage bipolar PRF adjacent to the dorsal root ganglion (DRG) reduced acute neuropathic pain in animals. By contrast, the present study investigated how PRF alters postsynaptic sensitization to produce early and delayed effects on neuropathic pain. OBJECTIVES: Our objective was to test the hypothesis that a 5-minute session of PRF could rapidly produce selective long-term depression (LTD) on C-fiber-mediated spinal sensitization and sustain the effect through the long-lasting inhibition of injury-induced ERK-MAPK activation. This may explain the prolonged analgesic effect of PRF on chronic neuropathic pain. STUDY DESIGN: Experiments were conducted on both normal rats and neuropathic pain rats that received spinal nerve ligation (SNL) 8 days prior. SETTING: An animal laboratory in a medical center of a university in Taiwan. METHODS: We first compared changes in field potentials in the L5 superficial spinal dorsal horn (SDH) that were evoked by conditioning electrical stimuli in the sciatic nerve in male adult rats before (as the baseline) and after PRF stimulation for at least 2 hours. Bipolar PRF was applied adjacent to the L5 DRG at an intensity of 5 V for 5 minutes, whereas the control rats were treated with sham applications. The electrophysiological findings were tested for any correlation with induction of spinal phospho-ERK (p-ERK) in normal and neuropathic pain rats. We then investigated the delayed effect of PRF on SNL-maintained pain behaviors for 2 weeks as well as p-ERK in SDH among the control, SNL, and PRF groups. Finally, potential injury in the DRGs after PRF stimulation was evaluated through behavioral observations and ATF-3, a neuronal stress marker. RESULTS: In the evoked field-potential study, the recordings mediated through A- and C-afferent fibers were identified as A-component and C-component, respectively. PRF significantly reduced the C-components over 2 hours in both the normal and SNL rats, but it did not affect the A-components. In the SNL rats, the C-component was significantly depressed in the PRF group compared with the sham group. PRF also inhibited acute p-ERK induced by mechanical nociception in both the control and SNL rats. For a longer period, PRF ameliorated SNL-maintained mechanical allodynia for 10 days and thermal analgesia for 14 days, and it significantly reduced late ERK activation within spinal neurons and astrocytes 14 days afterward. Moreover, PRF in the normal rats did not alter basal withdrawal thresholds or increase the expression and distribution of ATF-3 in the DRGs. LIMITATIONS: Several issues should be considered before translating the animal results to clinical applications. CONCLUSIONS: Low-voltage bipolar PRF produces LTD through selective suppression on the C-component, but not on the A-component. It also inhibits ERK activation within neurons and astrocytes in SDHs. The findings suggest that PRF alleviates long-lasting neuropathic pain by selectively and persistently modulating C-fiber-mediated spinal nociceptive hypersensitivity.Key words: Pulsed radiofrequency (PRF), dorsal root ganglion (DRG), neuropathic pain, ERK activation, evoked field potential, ATF-3, long-term depression (LTD), spinal nerve ligation (SNL).

Enhancing the Detection of Dysmorphic Red Blood Cells and Renal Tubular Epithelial Cells with a Modified Urinalysis Protocol.

Urinary sediment is used to evaluate patients with possible urinary tract diseases. Currently, numerous protocols are applied to detect dysmorphic red blood cells (RBCs) and renal tubular epithelial cells (RTECs) in urinary sediment. However, distinct protocols are used by nephrologists and medical technologists for specimen concentration and observation, which leads to major discrepancies in the differential counts of formed elements such as dysmorphic RBCs and RTECs and might interfere with an accurate clinical diagnosis. To resolve these problems, we first tested a modified urinalysis protocol with an increased relative centrifuge force and concentration factor in 20 biopsy-confirmed glomerulonephritis patients with haematuria. We successfully improved the recovery ratio of dysmorphic RBCs in clinical specimens from 34.7% to 42.0% (P < 0.001). Furthermore, we confirmed the correlation between counts by the modified urinary protocol and Sysmex UF-1000i urinary flow cytometer (r ≥ 0.898, P < 0.001). A total of 28 types of isomorphic and dysmorphic RBCs were detected using a bright field microscope, with results comparable to those using a standard phase contrast microscope. Finally, we applied Sternheimer stain to enhance the contrast of RTECs in the urinary sediments. We concluded that this modified urinalysis protocol significantly enhanced the quality of urinalysis.

Effect of polymyxin resistance (pmr) on biofilm formation of Cronobacter sakazakii.

Cronobacter sakazakii (C.sakazakii) has been identified as a wide-spread conditioned pathogen associated with series of serious illnesses, such as neonatal meningitis, enterocolitis, bacteremia or sepsis. As food safety is concerned, microbial biofilm has been considered to be a potential source of food contamination. The current study aims to investigate the ability of biofilm formation of two C. sakazakii strains (wild type BAA 894 and pmrA mutant). Crystal violet (CV), XTT (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino carbonyl)-2H-(tetrazolium hydroxide)] assays, and scanning electron microscopy (SEM) are performed on different time points during biofilm formation of C. sakazakii strains. Furthermore, RNA-seq strategy is utilized and the transcriptome data is analyzed to study the expression of genes related to biofilm formation along with whole genome sequencing. For biomass, in the first 24 h, pmrA mutant produced approximately 5 times than wildtype. However, the wild type exhibited more biomass than pmrA mutant during the post maturation stage (7-14 d). In addition, the wildtype showed higher viability than pmrA mutant during the whole biofilm formation. This study represents the first evidence on the biofilm formation of C. sakazakii pmrA mutant, which may further aid in the prevention and control for the food contamination caused by C. sakazakii.