Accurate and reliable surface-enhanced Raman spectroscopy assay for early detection of SARS-CoV-2 RNA with exceptional sensitivity.

This research proposes a highly sensitive and simple surface-enhanced Raman spectroscopy (SERS) assay for the detection of SARS-CoV-2 RNA using suitably designed probes specific for RdRp and N viral genes attached to a Raman marker. The sensitivity of the assay was optimized through precise adjustments to the conditions of immobilization and hybridization processes of the target RNA, including modifications to factors such as time and temperature. The assay achieved a remarkable sensitivity down to 58.39 copies/mL, comparable to or lower than the sensitivities reported for commercial fluorescent polymerase chain reaction (PCR) based methods. It has good selectivity in discriminating SARS-CoV-2 RNA against other respiratory viruses, respiratory syncytial virus (RSV), and influenza A virus. The reliability of the assay was validated by testing 24 clinical samples, including 12 positive samples with varying cycle threshold (Ct) values and 12 negative samples previously tested using real-time PCR. The assay consistently predicted true results that were in line with the PCR results for all samples. Furthermore, the assay demonstrated a notable limit of detection (LOD) of Ct (38 for RdRp gene and 37.5 for N-gene), indicating its capability to detect low concentrations of the target analyte and potentially facilitating early detection of the pathogen.

Recovery of facial nerve function after repair or grafting: our experience with 24 patients.

OBJECTIVE: The aim of this study was to review the outcomes of facial nerve repair and attempt to identify predictors of recovery time. STUDY DESIGN: A retrospective chart review was conducted. SETTING: The study was done in a single, tertiary care, otologic referral center. PATIENTS AND METHODS: Thirty-one patients underwent facial nerve repair or grafting between 1990 and 2003. Twenty-four patients were found to have complete data sets with at least 11-month follow-up. The following data were noted: patient age and sex, preoperative diagnosis and facial nerve status, administration of radiation, surgical procedure performed (including type and length of graft), proximal and distal sites of anastomosis, time interval to first recovery of clinical facial nerve function, and facial nerve status at most recent follow-up. RESULTS: Nineteen patients had some return of function within 12 months postoperatively. Five patients were lost to follow-up but had no documented facial function at a minimum of 11 months postoperatively. Mean follow-up was 8 months, with a range from 3 to 25 months. Overall mean time to recovery of function was 7 months. Mean times to recovery for each anastomotic site were calculated and found to correlate with recovery times, with an R(2) value of 0.86. A more proximal anastomosis was associated with a longer recovery period. When the data were analyzed individually, no statistical correlation was found between time to recovery of function and patient age, radiation status, length of graft, or site of anastomosis. CONCLUSIONS: Intuitively, because of technical difficulty and the proximity of injury to the cell body, a more proximal repair would seem to result in slower recovery. In our series of patients undergoing repair or grafting, neither the site of injury and repair nor the length of graft were statistically predictive of recovery intervals. A trend toward longer recovery time with a more proximal anastomosis is likely, however, based on the relationship identified between average recovery times and site of injury. A larger series is needed to identify a significant correlation.

Preauricular infratemporal fossa surgical approach: modifications of the technique and surgical indications.

A retrospective clinical analysis was performed to evaluate the effectiveness of the preauricular infratemporal fossa (ITF) surgical approach using modifications based on tumor pathology and extension, without compromising outcomes. Patients were surgically treated for tumors involving the ITF via a preauricular surgical approach during 1990 to 2000. Their clinical charts were reviewed to determine the association among pathological variables, details of the surgical procedure, and outcomes. Tumors in 65 patients were categorized as "malignant" and "benign." The malignant group included 44 patients (mean age, 49.5 years). Squamous cell carcinoma was the most common pathology followed by sarcomas. To achieve complete tumor resection, the ITF approach and dissection were combined with other procedures in 74% of these patients. No surgical complications were encountered in 74.4%, and a clinical cure was obtained in 55% of patients (follow-up, 2 years). The benign group included 21 patients (mean age, 36.7 years). Juvenile angiofibromas and meningiomas constituted most of the tumors in this group. An ITF approach alone was sufficient to achieve complete tumor excision in 66.7% of these patients. A clinical cure was achieved in 85% of patients (follow-up, 2 years), and 76.2% had no surgical complications. Chi-square tests revealed significant correlations between tumor extensions and surgical treatment variables. These were more evident in the malignant group, indicating the use of wider surgical exposures and more aggressive, extirpative surgery. The preauricular surgical approach to the ITF can be used to achieve a complete resection of a variety of tumors arising from or extending into the ITF. This approach can be tailored to the nature of the tumor and its extensions.

Association between tobacco use and metastatic neck disease.

OBJECTIVES/HYPOTHESIS: Tobacco has multiple effects on connective tissues that might affect tumor behavior. This study examined the association between tobacco use and tumor behavior (lymphatic metastasis and extracapsular spread) in head and neck cancers. STUDY DESIGN: Chart audit. METHODS: Medical records of patients from the Department of Otolaryngology, University of Pittsburgh Medical Center (Pittsburgh, PA) with oral cavity, pharyngeal, and laryngeal cancers who underwent neck dissection were reviewed focusing on their tobacco use habits, as well as the clinical and pathological criteria of primary tumors and cervical lymph nodes. Univariate and multivariate analyses were performed to study the significance between pathological and tobacco use variables. RESULTS: The study included 171 patients. Both univariate and multivariate analyses revealed significant associations between tobacco use and pathological findings. Cervical metastasis was observed in 100% of tobacco users and 54% of nonusers (P <.0001). Extracapsular spread was observed in 100% of tobacco users and 19% of nonusers (P <.0001). Tobacco use was independently associated with pathological nodal stage in multivariate analysis. Former users and light users of tobacco were not at reduced risk of cervical metastasis or extracapsular spread. CONCLUSIONS: The study demonstrates that tobacco use is a possible risk factor for cervical metastasis and extracapsular spread, which may be helpful information in planning therapy for patients with clinically staged node-negative necks.