Efficient detection of Streptococcus pyogenes based on recombinase polymerase amplification and lateral flow strip.

PURPOSE: This article aims to establish a rapid visual method for the detection of Streptococcus pyogenes (GAS) based on recombinase polymerase amplification (RPA) and lateral flow strip (LFS). METHODS: Utilizing speB of GAS as a template, RPA primers were designed, and basic RPA reactions were performed. To reduce the formation of primer dimers, base mismatch was introduced into primers. The probe was designed according to the forward primer, and the RPA-LFS system was established. According to the color results of the reaction system, the optimum reaction temperature and time were determined. Thirteen common clinical standard strains and 14 clinical samples of GAS were used to detect the selectivity of this method. The detection limit of this method was detected by using tenfold gradient dilution of GAS genome as template. One hundred fifty-six clinical samples were collected and compared with qPCR method and culture method. Kappa index and clinical application evaluation of the RPA-LFS were carried out. RESULTS: The enhanced RPA-LFS method demonstrates the ability to complete the amplification process within 6 min at 33 °C. This method exhibits a high analytic sensitivity, with the lowest detection limit of 0.908 ng, and does not exhibit cross-reaction with other pathogenic bacteria. CONCLUSIONS: The utilization of RPA and LFS allows for efficient and rapid testing of GAS, thereby serving as a valuable method for point-of-care testing.

Complicated placement of a nasogastric tube in the gastric mucosa: A case report and literature review.

Nasogastric tubes (NGTs) are commonly used in the intensive care unit (ICU) and are often inserted blindly at the bedside. Previous studies have highlighted various complications associated with NGT misplacement, including epistaxis, pneumothorax and even fatal perforations. To reduce the incidence of complications, guidelines recommend confirming the correct position of the NGT through radiography, pH testing, end-expiratory carbon dioxide monitoring, ultrasonography, etc. Herein, we present the case of a 78-year-old man who experienced sudden dyspnoea, was brought to the ICU and subsequently developed gastrointestinal bleeding following improper NGT placement. In this patient, air was rapidly injected down the NGT while auscultating for a 'whooshing sound' over the epigastrium. However, the correct position of the NGT was eventually confirmed by X-ray. Urgent upper gastrointestinal endoscopy revealed an oesophagogastric submucosal tunnelling of the NGT. This case emphasizes that auscultation may be unreliable and no longer encouraged. Additionally, various verification methods may not detect such rare complications related to NGT placement, making it necessary to focus on the emerging clinical manifestations following NGT insertion. Moreover, gaining further insight into the history of gastrointestinal diseases in patients may be beneficial. RELEVANCE TO CLINICAL PRACTICE: This case underscores the importance of noting resistance during a blind nasogastric tube (NGT) insertion in the intensive care unit (ICU). Additionally, the 'whooshing testing' for tube placement verification is not recommended. Although radiographic confirmation remains the gold standard, it may not effectively identify rare complications. Furthermore, emerging clinical signs (such as the abnormal nature of the gastrointestinal decompression drainage fluid, hypotension and anaemia) after insertion may suggest NGT misalignment. Finally, in urgent ICU settings, the patient's history of gastrointestinal disease should not be overlooked, as it can lead to complications such as gastrointestinal bleeding.

Lung Ultrasound in Emergency and Critically Ill Patients: Number of Supervised Exams to Reach Basic Competence.

BACKGROUND: Lung ultrasound is increasingly used in critically ill patients as an alternative to bedside chest radiography, but the best training method remains uncertain. This study describes a training curriculum allowing trainees to acquire basic competence. METHODS: This multicenter, prospective, and educational study was conducted in 10 Intensive Care Units in Brazil, China, France and Uruguay. One hundred residents, respiratory therapists, and critical care physicians without expertise in transthoracic ultrasound (trainees) were trained by 18 experts. The main study objective was to determine the number of supervised exams required to get the basic competence, defined as the trainees' ability to adequately classify lung regions with normal aeration, interstitial-alveolar syndrome, and lung consolidation. An initial 2-h video lecture provided the rationale for image formation and described the ultrasound patterns commonly observed in critically ill and emergency patients. Each trainee performed 25 bedside ultrasound examinations supervised by an expert. The progression in competence was assessed every five supervised examinations. In a new patient, 12 pulmonary regions were independently classified by the trainee and the expert. RESULTS: Progression in competence was derived from the analysis of 7,330 lung regions in 2,562 critically ill and emergency patients. After 25 supervised examinations, 80% of lung regions were adequately classified by trainees. The ultrasound examination mean duration was 8 to 10 min in experts and decreased from 19 to 12 min in trainees (after 5 vs. 25 supervised examinations). The median training duration was 52 (42, 82) days. CONCLUSIONS: A training curriculum including 25 transthoracic ultrasound examinations supervised by an expert provides the basic skills for diagnosing normal lung aeration, interstitial-alveolar syndrome, and consolidation in emergency and critically ill patients.

Bedside Ultrasound Assessment of Lung Reaeration in Patients With Blunt Thoracic Injury Receiving High-Flow Nasal Cannula Oxygen Therapy: A Retrospective Study.

BACKGROUND: High-flow nasal cannula (HFNC) oxygen therapy has been shown to reduce the need for mechanical ventilation and decrease the duration of hospital and intensive care unit (ICU) stays for patients with a severely compromised respiratory system. This study aims to observe the evolution of lung aeration via lung ultrasound score (LUS) in a chest-injured population who had been treated with HFNC oxygen therapy, and to assess the benefit of the HFNC oxygen therapy in trauma patients. METHODS: A retrospective study examined trauma patients with moderate to severe thoracic injuries who were admitted to the ICU at a tertiary hospital between October 2015 and March 2017. The decision to initiate HFNC oxygen therapy was made at the discretion of the trauma surgeon and respiratory therapist when supplemental oxygen delivery was required. All of the patients were assessed by transthoracic lung ultrasound every day after being admitted into the ICU. We retrospectively analyzed 3 time points for this study: the initial emergency intensive care units presentation within 12 hours (T1), 24 to 48 hours after the treatment (T2), and 72 to 96 hours after the treatment (T3). Transthoracic lung ultrasound was performed by an experienced investigator with level 3 certification using a Mindray M9 echograph and a 2- to 4-MHz round-tipped probe. Primary outcomes were the need for intubation after HFNC oxygen therapy for respiratory failure during the treatment within 72 hours, the length of ICU stay, and mortality of 28 days. RESULTS: During the study period, 50 patients with blunt chest trauma were admitted to the study; 18 patients received HFNC therapy and 32 received conventional oxygen therapy (COT); there was no significant difference in the baseline clinical characteristics between the 2 groups. The length of ICU stay and intubation rate for respiratory failure within 72 hours were significantly different between the 2 groups (P < .05), but there was no difference in the 28-day mortality. The LUS of the COT group was not significantly different from T1 to T2 or from T2 to T3 (P > .05). However, the LUS decreased significantly-by 25% from T1 to T2 (P < .05) and by 31% from T1 to T3 (P < .05) in the HFNC therapy group. The LUS of the patients intubated for respiratory failure within 72 hours, in the COT group increased from T1 (17 ± 3) to T3 (21 ± 3), and the LUS (21 ± 3) was much higher than the patients who were not intubated (11 ± 3) at T3; the LUS of the HFNC group was all above 15, which was not significantly different from T1 to T2 or from T2 to T3 (P > .05). CONCLUSIONS: High-flow nasal cannula oxygen therapy may be considered as an initial respiratory therapy for trauma patients with blunt chest injury. High-flow nasal cannula therapy could improve lung aeration as noted by the transthoracic lung ultrasound assessment, and LUS may help the attending physicians identify the usefulness of HFNC therapy and decide whether to continue the use of HFNC therapy or intubate the patient.

Use of a Doppler-Based Pulsatility Index to Evaluate Cerebral Hemodynamics in Neurocritical Patients After Hemicraniectomy.

OBJECTIVES: As a noninvasive method for evaluation of cerebral hemodynamics, the correct interpretation of transcranial Doppler or transcranial imaging (TCI) data remains a major challenge. We explored how to interpret the pulsatility index (PI) derived via TCI during evaluations of cerebral hemodynamics in posthemicraniectomy patients. METHODS: We included patients who underwent invasive arterial pressure and intracranial pressure (ICP) monitoring and simultaneous TCI examinations after hemicraniectomy. We classified the PI of the middle cerebral artery (MCA) into ipsilateral (craniectomy side) and contralateral (opposite side) and analyzed both data sets. The statistical analysis was performed by the Bland-Altman approach, by calculating intraclass correlation coefficients and Spearman correlations, and by drawing receiver operating characteristic curves. Pulsatility index probability charts were created for ICPs exceeding 20, 25, and 30 mm Hg and cerebral perfusion pressures (CPPs) lower than 70, 60, and 50 mm Hg; we thus explored defined ICP and CPP values. RESULTS: The ipsilateral and contralateral MCA PI data differed. Only the ipsilateral MCA PI showed a weak correlation with ICP (r = 0.378; P < .001). The receiver operating characteristic curve analysis revealed limited diagnostic utility of bilateral MCA PIs for ICP and CPP assessments. An extremely elevated MCA PI indicated that patients were at high risk of a dangerous ICP elevation or CPP reduction. However, MCA PI values within the normal range did not effectively rule out an ICP of 20 mm Hg or higher but effectively eliminated a CPP lower than 50 mm Hg. CONCLUSIONS: In posthemicraniectomy patients, the Doppler-based MCA PI value was ineffectively for quantitative ICP and CPP evaluations but a useful index for assessment of cerebral hemodynamics in terms of the probability of an ICP elevation or a CPP reduction.

Diagnostic and prognostic value of the optic nerve sheath diameter with respect to the intracranial pressure and neurological outcome of patients following hemicraniectomy.

BACKGROUND: In cases showing cerebrospinal fluid (CSF) redistribution as a compensatory mechanism in acute intracranial hypertension, the optic nerve sheath diameter (ONSD) can be used to estimate intracranial pressure (ICP). However, it remains unclear whether the ONSD can be applied in patients with skull defects after a craniectomy, because the primary injury or surgical craniectomy may alter the dynamics of the CSF circulation or structure of the optical nerve sheath. This study explored the value of the ONSD in patients after a hemicraniectomy. METHODS: This prospective observational study enrolled patients after a hemicraniectomy. All patients underwent invasive ICP monitoring and ocular ultrasound within 6 h postoperatively. We followed the patients for 6 months and evaluated them using the Glasgow Outcome Score (GOS), classifying the outcome as favorable (GOS 4-5) or unfavorable (GOS 1-3). We evaluated the ONSD in both according to the ICP and neurological outcome. RESULTS: Of the 33 enrolled patients, 20 (60.6%) had an unfavorable outcome at 6 months. Disagreement was seen in the ONSD measurements between the eyes [craniectomy side (ONSDips) and opposite side (ONSDcon)]. The intraclass correlation coefficient between ONSDips and ONSDcon was 0.745 (p < 0.001). ONSD had no significant correlation with ICP in Spearman correlation analysis (ONSDips r = 0.205, p = 0.252; ONSDcon r = 0.164, p = 0.362). Receiver operator characteristic (ROC) curve analysis revealed that the GCS, Helsinki computed tomography (CT) score, pupil reaction, and ONSDcon measured after the craniectomy were significantly associated with a poor outcome. ONSDcon > 5.5 mm predicted a poor outcome, with an area under the ROC curve of 0.717 (95% confidence interval, 0.534-0.860, p = 0.02), 70% sensitivity, and 69.2% specificity. CONCLUSIONS: After hemicraniectomy, the ONSD measured on ultrasound was unreliable for evaluating ICP, but showed potential prognostic value for a poor neurological outcome.

Performance Enhancement via Incorporation of ZnO Nanolayers in Energetic Al/CuO Multilayers.

Al/CuO energetic structure are attractive materials due to their high thermal output and propensity to produce gas. They are widely used to bond components or as next generation of MEMS igniters. In such systems, the reaction process is largely dominated by the outward migration of oxygen atoms from the CuO matrix toward the aluminum layers, and many recent studies have already demonstrated that the interfacial nanolayer between the two reactive layers plays a major role in the material properties. Here we demonstrate that the ALD deposition of a thin ZnO layer on the CuO prior to Al deposition (by sputtering) leads to a substantial increase in the efficiency of the overall reaction. The CuO/ZnO/Al foils generate 98% of their theoretical enthalpy within a single reaction at 900 °C, whereas conventional ZnO-free CuO/Al foils produce only 78% of their theoretical enthalpy, distributed over two distinct reaction steps at 550 °C and 850 °C. Combining high-resolution transmission electron microscopy, X-ray diffraction, and differential scanning calorimetry, we characterized the successive formation of a thin zinc aluminate (ZnAl2O4) and zinc oxide interfacial layers, which act as an effective barrier layer against oxygen diffusion at low temperature.

Probing the Structure, Composition, and Spatial Distribution of Ligands on Gold Nanorods.

The structure and size of ligands attached to the surfaces of gold nanorods, such as adsorbed surfactants or grafted polymers, are important considerations that facilitate the use of such nanoparticles in the human body, in advanced materials for energy harvesting, or in devices for single molecule detection. Here, we report small-angle neutron scattering (SANS) measurements from surfactant or poly(ethylene glycol) (PEG) coated gold nanorods in solution, which quantitatively determine the location, structure, and composition of these surface layers. In addition, by synthesizing gold nanorods using seed crystals which are coated with deuterated cetyltrimethylammonium bromide (dCTAB), we are able to exploit the isotopic sensitivity of SANS to study, for the first time, the retention of surfactant from the seed crystals to the final gold nanorod product, finding that very little exchange of the deuterated with hydrogenated surfactant occurs. Finally, we demonstrate that, when Au NRs are PEGylated using standard techniques, the surfactant bilayer remains intact, and while mass spectrometry detects the presence of both surfactant and PEG, the composition as measured from SANS is predominantly that of the surfactant. These measurements not only provide new insight into the synthesis and functionalization of gold nanorods but provide a quantitative picture of the structure of grafted polymer and surfactant layers on gold nanorod surfaces which has implications for the fabrication of plasmonic and biomedical materials.

Using binary surfactant mixtures to simultaneously improve the dimensional tunability and monodispersity in the seeded growth of gold nanorods.

We report a dramatically improved synthesis of colloidal gold nanorods (NRs) using a binary surfactant mixture composed of hexadecyltrimethylammonium bromide (CTAB) and sodium oleate (NaOL). Both thin (diameter <25 nm) and thicker (diameter >30 nm) gold NRs with exceptional monodispersity and broadly tunable longitudinal surface plasmon resonance can be synthesized using seeded growth at reduced CTAB concentrations (as low as 0.037 M). The CTAB-NaOL binary surfactant mixture overcomes the difficulty of growing uniform thick gold NRs often associated with the single-component CTAB system and greatly expands the dimensions of gold NRs that are accessible through a one-pot seeded growth process. Gold NRs with large overall dimensions and thus high scattering/absorption ratios are ideal for scattering-based applications such as biolabeling as well as the enhancement of optical processes.

Seeded growth of monodisperse gold nanorods using bromide-free surfactant mixtures.

We demonstrate for the first time that monodisperse gold nanorods (NRs) with broadly tunable dimensions and longitudinal surface plasmon resonances can be synthesized using a bromide-free surfactant mixture composed of alkyltrimethylammonium chloride and sodium oleate. It is found that uniform gold NRs can be obtained even with an iodide concentration approaching 100 µM in the growth solution. In contrast to conventional wisdom, our results provide conclusive evidence that neither bromide as the surfactant counterion nor a high concentration of bromide ions in the growth solution is essential for gold NR formation. Correlated electron microscopy study of three-dimensional structures of gold NRs reveals a previously unprecedented octagonal prismatic structure enclosed predominantly by high index {310} crystal planes. These findings should have profound implications for a comprehensive mechanistic understanding of seeded growth of anisotropic metal nanocrystals.

[Assessment of positive end-expiratory pressure induced lung volume change by ultrasound in mechanically ventilated patients].

OBJECTIVE: To investigate the value of lung ultrasound for assessing positive end-expiratory pressure (PEEP) -induced lung volume change in mechanically ventilated patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) . METHODS: Eighteen patients with ALI or ARDS were prospectively studied. P-V curves and lung ultrasound were performed at PEEP 12, 8, 4 and 0 cm H2O (1 cm H2O = 0.098 kPa). PEEP-induced lung volume change was measured using the P-V curve method and lung ultrasound. RESULTS: Four lung ultrasound entities were defined: consolidation, multiple irregularly spaced B lines, multiple abutting B lines and normal aeration.For each of the 12 lung regions examined, PEEP-induced ultrasound changes were measured and an lung ultrasound score (LUS) was calculated. A highly significant correlation was found between PEEP-induced lung volume change measured by P-V curves and LUS change (r = 0.82, P < 0.01) . A statistically significant correlation was found between LUS change and PEEP-induced increase in PaO2 (r = 0.66, P < 0.01). CONCLUSION: PEEP-induced lung volume change can be adequately estimated with bedside lung ultrasound. Since lung ultrasound cannot assess PEEP-induced lung hyperinflation, it should not be the sole method for PEEP titration.

Anti-papillary thyroid carcinoma effects of dioscorea bulbifera L. through ferroptosis and the PI3K/AKT pathway based on network pharmacology and experimental validation.

ETHNOPHARMACOLOGICAL RELEVANCE: Papillary thyroid carcinoma (PTC) is the predominant form of thyroid cancer with a rising global incidence. Despite favorable prognoses, a significant recurrence rate persists. Dioscorea bulbifera L. (DBL), a traditional Chinese medicine, has been historically used for thyroid-related disorders. However, its therapeutic effects and mechanisms of action on PTC remain unclear. AIM OF THE STUDY: To explore the potential therapeutic effects, principal active components, and molecular mechanisms of DBL in the treatment of PTC through network pharmacology and molecular docking, with experimental validation conducted to corroborate these findings. MATERIALS AND METHODS: The Traditional Chinese Medicine Systems Pharmacology Database (TCMSP) was utilized as a systematic tool for collecting and screening the phytochemical components of DBL, and for establishing associations between these components and molecular targets. Based on this, network data was visually processed using Cytoscape software (version 3.8.0). Concurrently, precise molecular docking studies of the principal active components of DBL and their corresponding targets were conducted using Autodock software. Additionally, PTC-related genes were selected through the GeneCards and GEO databases. We further employed the DAVID bioinformatics resources to conduct comprehensive Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses on the intersecting genes between DBL and PTC. These analyses aid in predicting the potential therapeutic actions of DBL on PTC and its mechanisms of action. To validate these findings, corresponding in vitro experimental studies were also conducted. RESULTS: In this investigation, 14 bioactive compounds of DBL and 195 corresponding molecular targets were identified, with 127 common targets shared between DBL and PTC. Molecular docking revealed strong binding affinities between major bioactive compounds and target proteins. GO enrichment analysis unveiled key processes involved in DBL's action. KEGG analysis highlighted DBL's modulation of the PI3K/AKT signaling pathway. Experimental outcomes demonstrated DBL's potential in inhibiting PTC cell proliferation and migration, suppressing PI3K/AKT pathway activation, and promoting ferroptosis. CONCLUSION: In conclusion, DBL offers a multifaceted therapeutic approach for PTC, targeting multiple molecular entities and influencing diverse biological pathways. Network pharmacology and molecular docking shed light on DBL's potential utility in PTC treatment, substantiated by experimental validation. This study contributes valuable insights into using DBL as a promising therapeutic agent for PTC management.

Development and application of a rapid visual detection technique for VanA gene in vancomycin-resistant Enterococcus faecium.

The objective of this study was to establish a rapid visual diagnosis method for vancomycin-resistant Enterococcus faecium (VREFm) based on multienzyme isothermal rapid amplification (MIRA) combined with lateral flow strips (LFSs). The MIRA primers and probes were specifically designed to maintain the sequence of the VanA gene of VREFm. We optimized the reaction time and temperature and thoroughly assessed the specificity and sensitivity of the MIRA-LFS system. We also compared the MIRA-LFS method with the polymerase chain reaction (PCR) assay and the disc diffusion method. We then evaluated the MIRA-LFS assay for consistency testing and clinical application. The MIRA-LFS technique completed the amplification process within 30 min, and the results were observed on LFS. The method demonstrated high sensitivity, with a minimum detection limit of 1.066 CFU/µL for VREFm and exhibited specificity without cross-reactivity with other pathogenic bacteria. When applied to the detection of clinical samples, the method exhibited consistency with the PCR and agar dilution methods. The combined use of MIRA and LFS in this study facilitates simplifying the workflow for detecting VREFm, which is of great significance for rapidly detecting the enterococcal infections and preventing and controlling the nosocomial infections. IMPORTANCE: One of the key approaches to treating and controlling vancomycin-resistant Enterococcus faecium (VREFm) is an accurate and rapid diagnosis. To achieve this goal, a simple and rapid method must be constructed for immediate detection in the field. Multienzyme isothermal rapid amplification (MIRA) is an isothermal rapid amplification method that allows amplification reactions to be completed under room temperature conditions. When combined with lateral flow strips (LFSs), MIRA-LFS enables the rapid detection of pathogenic microorganisms. However, the MIRA method often produces false signals. These false signals are eliminated by using base mismatches introduced in primers and probes. The MIRA-LFS system was constructed with high specificity and sensitivity for the detection of VREfm, without the limitation of sophisticated instruments. This enables the prompt formulation of diagnostic and therapeutic decisions.

Establishment and application of a rapid visual diagnostic method for Streptococcus agalactiae based on recombinase polymerase amplification and lateral flow strips.

This study aims to establish a rapid diagnostic method for Streptococcus agalactiae (GBS) based on recombinase polymerase amplification (RPA) and lateral flow strips (LFS). The best primer pairs designed by SIP gene were screened according to the basic RPA reaction, then the probe was designed. The reaction condition was optimized based on the color development of the LFS detection line. To ascertain the reaction specificity, 10 common clinical pathogens and 10 clinical specimens of GBS were tested. Furthermore, the reaction sensitivity was assessed by utilizing a tenfold gradient dilution of GBS genomic DNA as templates. RPA-LFS method was compared to the qPCR assay and biochemical culture method for the Kappa consistency test. The RPA-LFS technique was able to complete the amplification process within 30 min and the results were observed on lateral flow strips. The method is highly sensitive, with a minimum detection limit of 1.31 ng for GBS. The RPA-LFS method showed consistent accuracy of results compared to qPCR and the culture-biochemical method. The establishment of this method is conducive to the development of on-site immediate detection, which can provide information for the timely development of a reasonable antimicrobial treatment plan, and has a greater potential for clinical application.

A rapid and visual detection of Staphylococcus haemolyticus in clinical specimens with RPA-LFS.

Staphylococcus haemolyticus (S. haemolyticus), which is highly prevent in the hospital environment, is an etiological factor for nosocomial infections. Point-of-care rapid testing (POCT) of S. haemolyticus is not possible with the currently used detection methods. Recombinase polymerase amplification (RPA) is a novel isothermal amplification technology with high sensitivity and specificity. The combination of RPA and lateral flow strips (LFS) can achieve rapid pathogen detection, enabling POCT. This study developed an RPA-LFS methodology using a specific probe/primer pair to identify S. haemolyticus. A basic RPA reaction was performed to screen the specific primer from 6 primer pairs targeting mvaA gene. The optimal primer pair was selected based on agarose gel electrophoresis, and the probe was designed. To eliminate false-positive results caused by the byproducts, base mismatches were introduced in the primer/probe pair. The improved primer/probe pair could specifically identify the target sequence. To explore the optimal reaction conditions, the effects of reaction temperature and duration of the RPA-LFS method were systematically investigated. The improved system enabled optimal amplification at 37 °C for 8 min, and the results were visualized within 1 min. The S. haemolyticus detection sensitivity of the RPA-LFS method, whose performance was unaffected by contamination with other genomes, was 0.147 CFU/reaction. Furthermore, we analyzed 95 random clinical samples with RPA-LFS, quantitative polymerase chain reaction (qPCR), and traditional bacterial-culture assays and found that the RPA-LFS had 100% and 98.73% compliance rates with the qPCR and traditional culture method, respectively, which confirms its clinical applicability. In this study, we designed an improved RPA-LFS assay based on the specific probe/primer pair for the detection of S. haemolyticus via rapid POCT, free from the limitations of the precision instruments, helping to make diagnoses and treatment decisions as soon as possible.

An improved recombinase polymerase amplification assay for the visual detection of Staphylococcus epidermidis with lateral flow strips.

Staphylococcus epidermidis is an opportunistic pathogenic microorganism that is an important cause of cross-infection in hospitals. The development of rapid and effective detection techniques is important for its control. The application of traditional identification and PCR-based methods is limited by their requirements for both laboratory instrumentation and trained personnel. To overcome this issue, we developed a fast detection approach for S. epidermidis that was based on recombinase polymerase amplification (RPA) and lateral flow strips (LFS). First, five pairs of primers were designed for molecular diagnosis using the sesB gene as the target, and were screened for their amplification performance and the formation of primer dimers. Specific probes were then designed based on the best primer pairs screened, which were susceptible to primer-dependent artifacts and generated false-positive signals when used for LFS detection. This weakness of the LFS assay was overcome by modifying the sequences of the primers and probes. The efficacy of these measures was rigorously tested, and improved the RPA-LFS system. Standardized systems completed the amplification process within 25 min at a constant temperature of 37 °C, followed by visualization of the LFS within 3 min. The approach was very sensitive (with a detection limit of 8.91 CFU/µL), with very good interspecies specificity. In the analysis of clinical samples, the approach produced results consistent with PCR and 97.78% consistent with the culture-biochemical method, with a kappa index of 0.938. Our method was rapid, accurate, and less dependent on equipment and trained personnel than traditional methods, and provided information for the timely development of rational antimicrobial treatment plans. It has high potential utility in clinical settings, particularly in resource-constrained locations.

Rapid detection of recurrent intraventricular hemorrhage by ultrasound in a multiple trauma patient who had undergone craniectomy.

Ultrasound may be a useful tool to evaluate intracranial abnormalities in critically ill patients undergoing decompressive craniectomy. We present a multiple trauma patient who had undergone craniectomy and in whom recurrent intraventricular hemorrhage and patterns of cerebral blood flow were rapidly detected by ultrasound.

Hemocompatibility investigation of the NiTi alloy implanted with tantalum.

A composite TiO(2)/Ta(2)O(5) nano-film has been formed on the NiTi shape memory alloy by Ta implantation. The wettability, protein adsorption, platelets adhesion and hemolysis tests are conducted to evaluate the hemocompatibility. The contact angle measurements showed that the surface of the NiTi alloy kept hydrophilic before and after Ta implantation, although the water contact angle increased with the increasing of implantation current. Both of the surface energy and the interfacial tension decreased after Ta implantation. The protein adsorption behavior was investigated by (125)I isotope labeling. The fibrinogen adsorption was enhanced by a high surface roughness or a large interfacial tension, while the albumin adsorption was insensitive to the surface modification. Platelet adhesion and activation were weakened and the hemolysis rate was reduced at least 46% after Ta implantation due to the decreased surface energy and improved corrosion resistance ability, respectively.