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.

The Potential Immunomodulatory Properties of Levornidazole Contribute to Improvement in Experimental Ulcerative Colitis.

The use of an antibiotic with immunomodulatory properties could be fascinating in treating multifactorial inflammatory conditions such as ulcerative colitis (UC). We report our investigations into the immunomodulatory properties of levornidazole, the S-enantiomer of ornidazole, which displayed a tremendous therapeutic potential in UC induced by dextran sodium sulfate (DSS). Levornidazole administration to DSS-colitic mice attenuated the intestinal inflammatory process, with an efficacy better than that shown by 5-amino salicylic acid. This was evidenced by decreased disease activity index, ameliorated macroscopic and microscopic colon damages, and reduced expression of inflammatory cytokines. Additionally, levornidazole displayed anti-inflammatory activity through Caveolin-1-dependent reducing IL-1ß and IL-18 secretion by macrophages contributing to its improvement of the intestinal inflammation, as confirmed in vitro and in vivo. In conclusion, these results pointed out that the immunomodulatory effects of levornidazole played a vital role in ameliorating the intestinal inflammatory process, which would be crucial for the translation of its use into clinical settings.

Establishment of a swine model of traumatic cardiac arrest induced by haemorrhage and ventricular fibrillation.

OBJECTIVE: To establish and evaluate a swine model of traumatic cardiac arrest (TCA) induced by haemorrhage and ventricular fibrillation. METHODS: Thirteen male pigs were divided into a sham group (n = 5) and TCA group (n = 8). Animals in the sham-operated group underwent intubation and monitoring but not haemorrhage and resuscitation, while animals in the TCA group underwent 40% blood volume haemorrhage over 20 min followed by 5 min of ventricular fibrillation and 5 min of cardiopulmonary resuscitation with fluid resuscitation. RESULTS: Restoration of spontaneous circulation was achieved in seven of eight animals in the TCA group. After resuscitation, the heart rate was significantly increased while the mean arterial pressure and ejection fraction were significantly decreased in the TCA group. The TCA group had significant cardiac and neurological injuries post-resuscitation and had higher serum creatinine and blood lactic acid levels and lower PaO2 than the sham group. Animals in the TCA group also exhibited significantly higher apoptotic indices and caspase-3 protein levels in the heart, brain and kidney than the sham group. CONCLUSION: Animals in this swine model of TCA exhibited high rates of successful resuscitation, significant vital organ injury and prolonged survival. The model is suitable for use in further TCA research.

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.

Factors influencing outcomes after cardiopulmonary resuscitation in emergency department.

BACKGROUND: The outcome of cardiopulmonary resuscitation (CPR) may depend on a variety of factors related to patient status or resuscitation management. To evaluate the factors influencing the outcome of CPR after cardiac arrest (CA) will be conducive to improve the effectiveness of resuscitation. Therefore, a study was designed to assess these factors in the emergency department (ED) of a city hospital. METHODS: A CPR registry conforming to the Utstein-style template was conducted in the ED of the First Affiliated Hospital of Wenzhou Medical College from January 2005 to December 2011. The outcomes of CPR were compared in various factors groups. The primary outcomes were rated to return of spontaneous circulation (ROSC), 24-hour survival, survival to discharge and discharge with favorable neurological outcomes. Univariate analysis and multivariable logistic regression analysis were performed to evaluate factors associated with survival. RESULTS: A total of 725 patients were analyzed in the study. Of these patients, 187 (25.8%) had ROSC, 100 (13.8%) survived for 24 hours, 48 (6.6%) survived to discharge, and 23 (3.2%) survived to discharge with favorable neurologic outcomes. A logistic regression analysis demonstrated that the independent predictors of ROSC included traumatic etiology, first monitored rhythms, CPR duration, and total adrenaline dose. The independent predictors of 24-hour survival included traumatic etiology, cardiac etiology, first monitored rhythm and CPR duration. Previous status, cardiac etiology, first monitored rhythms and CPR duration were included in independent predictors of survival to discharge and neurologically favorable survival to discharge. CONCLUSIONS: Shockable rhythms, CPR duration ≤15 minutes and total adrenaline dose ≤5 mg were favorable predictors of ROSC, whereas traumatic etiology was unfavorable. Cardiac etiology, shockable rhythms and CPR duration ≤15 minutes were favorable predictors of 24-hour survival, whereas traumatic etiology was unfavorable. Cardiac etiology, shockable rhythms, CPR duration ≤15 minutes were favorable predictors of survival to discharge and neurologically favorable survival to discharge, but previous terminal illness or multiple organ failure (MOF) was unfavorable.

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.