The Latest Achievements in the Construction of Influenza Virus Detection Aptasensors

Aptamers are short fragments of nucleic acids, DNA or RNA that have the ability to bind selected proteins with high specificity and affinity. These properties allow them to be used as an element of biosensors for the detection of specific proteins, including viral ones, which makes it possible to design valuable diagnostic tools. The influenza virus causes a huge number of human and animal deaths worldwide every year, and contributes to remarkable economic losses. In addition, in 2020, a new threat appeared—the SARS-Cov-2 pandemic. Both disease entities, especially in the initial stage of infection, are almost identical in terms of signs and symptoms. Therefore, a diagnostic solution is needed that will allow distinguishing between both pathogens, with high sensitivity and specificity; it should be cheap, quick and possible to use in the field, for example, in a doctor’s office. All the mentioned properties are met by aptasensors in which the detection elements are specific aptamers. We present here the latest developments in the construction of various types of aptasensors for the detection of influenza virus. Aptasensor operation is based on the measurement of changes in electric impedance, fluorescence or electric signal (impedimetric, fluorescence and electrochemical aptasensors, respectively); it allows both qualitative and quantitative determinations. The particularly high advancement for detecting of influenza virus concerns impedimetric aptasensors.     

Exposure equalization radiography of the chest: clinical comparison of slit and raster scanning techniques

Exposure equalization radiography systems with scanning slit and raster geometries were constructed and tested with 75 patients. The scanning equalization radiography (SER) technique uses a detector, placed behind the patient, connected in a feedback loop to a microprocessor-controlled x-ray source. The detector monitors the transmitted radiation, and in turn the x-ray output is varied to equalize the radiographic film density over the entire image. The clinical evaluation of these systems included 25 posteroanterior (PA) chest radiographs by an SER slit-geometry system (5.0-sec scan time), 25 PA chest radiographs by an SER raster-geometry system with an 8.8-sec scan time, and 25 PA chest radiographs by an SER raster-geometry system with a 4.7-sec scan time. These SER radiographs were compared to conventional radiographs of the same patients by two radiologists. The observers noted that the SER slit radiographs had seriously overexposed areas in 80% of instances, and that any potential gains from this system were offset by the overexposure problems. The radiographs obtained by the SER raster technique with a 4.7-sec scan time showed more uniform and adequate exposure in 80% of instances and better visualization of normal anatomic detail in the lung (52%) and mediastinum (84%) than conventional radiographs. The radiographs obtained by the SER raster technique with an 8.8-sec scan time showed fewer peripheral lung markings in 15 of 25 cases, presumably due to motion. In all other respects, the images were similar in quality to the SER raster 4.7-sec radiographs.     

Comparing thin-section and thick-section CT of pericardial sinuses and recesses

OBJECTIVE: The aim of this study was to assess the prevalence and appearance of the pericardial sinuses and recesses on thin-section (2.5- or 3-mm) CT scans compared with thick-section (5- or 7-mm) CT scans. MATERIALS AND METHODS: Nine hundred forty-one consecutive contrast-enhanced chest CT scans were retrospectively evaluated. Three hundred sixty-five patients underwent thin-section CT, and 576 patients underwent thick-section CT. The prevalence and appearance of every pericardial recess were determined. RESULTS: Large recesses such as the superior aortic recess were depicted in 12.5-30.4% of patients using thick-section CT, whereas smaller recesses such as the postcaval recess were depicted in fewer than 5% of patients. With thin-section CT, the depiction rates increased significantly compared with thick-section CT (p < 0.01). Large recesses were depicted in 28.7-44.7% of patients, and smaller recesses were recognized in 10.8-19.8% of patients. Generally, most recesses were linear if they were small and became band-shaped as the fluid increased. However, the recesses were often visualized as crescent, triangle, spindle, ovoid, hemisphere, or irregular shapes. CONCLUSION: Pericardial sinuses and recesses are more frequently and better depicted on thin-section CT scans. Knowledge of their locations and shapes is helpful for distinguishing pericardial fluid from abnormal findings such as lymphadenopathy and cystic lesions.     

Aptamers in Diagnostics and Treatment of Viral Infections

Aptamers are in vitro selected DNA or RNA molecules that are capable of binding a wide range of nucleic and non-nucleic acid molecules with high affinity and specificity. They have been conducted through the process known as SELEX (Systematic Evolution of Ligands by Exponential Enrichment). It serves to reach specificity and considerable affinity to target molecules, including those of viral origin, both proteins and nucleic acids. Properties of aptamers allow detecting virus infected cells or viruses themselves and make them competitive to monoclonal antibodies. Specific aptamers can be used to interfere in each stage of the viral replication cycle and also inhibit its penetration into cells. Many current studies have reported possible application of aptamers as a treatment or diagnostic tool in viral infections, e.g., HIV (Human Immunodeficiency Virus), HBV (Hepatitis B Virus), HCV (Hepatitis C Virus), SARS (Severe Acute Respiratory Syndrome), H5N1 avian influenza and recently spread Ebola. This review presents current developments of using aptamers in the diagnostics and treatment of viral diseases.     

Detection and diagnosis of nonpalpable supraclavicular lymph nodes in lung cancer at CT and US.

PURPOSE: To assess frequency and significance of enlarged nonpalpable supraclavicular lymph nodes by using chest computed tomography (CT) and supraclavicular ultrasonography (US) in patients at initial diagnosis of lung cancer. MATERIALS AND METHODS: Fifty-five patients with no prior malignancy who presented with suspected and subsequently proven lung cancer of any stage or a proven but potentially resectable lung cancer were prospectively selected after chest CT. Chest CT and other radiologic findings were reviewed and tabulated. Standardized US technique was used to identify and guide needle biopsy of enlarged supraclavicular lymph nodes (> or =0.5 cm short axis). RESULTS: Twenty-two (40%) of 55 patients had supraclavicular abnormalities detected at CT and/or US. In 18 (82%) of the 22 patients, supraclavicular abnormalities were recognizable at CT. Seventeen of 22 patients had malignant nodes, and five patients had benign nodes (n = 3), a cyst (n = 1), or an indeterminate lesion (n = 1) at US-guided supraclavicular needle sampling. There were no complications. Supraclavicular metastases (31% of patients) were about as common as the combined number of patients with indeterminate (n = 13) and probably or proven malignant (n = 6) adrenal nodules (35% of patients). Supraclavicular metastases were often associated with mediastinal adenopathy or suspected extrapulmonary nonnodal metastases (P <.05). CONCLUSION: In many patients with lung cancer, chest CT that includes the neck base followed by US-guided sampling of enlarged supraclavicular lymph nodes is a simple and safe method for simultaneously establishing a tissue diagnosis and tumor nonresectability.     

Systematic review of periprosthetic tibia fracture after total knee arthroplasties

AIM: To investigate the known incidences, treatment options, and related outcomes of periprosthetic tibia fractures after total knee arthroplasty (TKA).METHODS: A literature search was done to identify studies that fit the inclusion criteria. The database search yielded 185 results, which were further reduced by the exclusion criteria to 13 papers, totaling 157 patients that met these criteria. Incidence rates of the different types of periprosthetic tibia fractures were determined and their treatments were subsequently analyzed based on the fracture’s subclass, with patient outcomes being overall favorable.RESULTS: Of the 144 documented patients, 54 (37.5%) had a subclass C fracture, which are frequently seen in revision arthroplasties or when using cement intraoperatively. The fractures of subclasses A and B occur postoperatively. There were 90 subclass A and B fractures with incidences of 18.75% and 43.75% respectively. When broken down by type, 62 (55.36%) were type 1, 24 (21.4%) were type 2, 24 (21.4%) were type 3, and 2 (1.8%) were type 4. Furthermore, from the studies that included origin of injury, the types were further classified as having non-traumatic or traumatic origins. Type 1 had 78% (40/51) non-traumatic origin and 22% (11/51) traumatic origin. Fifteen fractures were type 2, but 5 were falls and 1 through a motor vehicle accident, giving a trauma causation of 40% (6/15). Of the 24 type 3 fractures, 12 were falls and 2 vehicular accidents, leading to a trauma causation of 58% (14/24).CONCLUSION: Type 1 fractures were the most common. Subclass A was treated with locking plates, B required a revision TKA, and C was treated intraoperatively or nonoperatively.     

Pulmonary fat embolism after pelvic and long bone fractures in a trauma patient

Fat embolism is a common complication of pelvic and long bone fractures. Macroscopic fat emboli in the pulmonary arteries on computed tomography have been reported postoperatively after fixation of long bone fractures for trauma, however the quantification of attenuation values of fat emboli have been infrequently reported in the literature. We present a case of pulmonary fat embolism in a 52-year-old female after acute bony trauma sustained during a motor vehicle accident. To the authors' knowledge however, pulmonary fat embolism has not been described on the initial trauma CT scan.     

A Systematic Review of Total Dislocation of the Talus

This review summarizes the treatment and resulting outcomes for total talar dislocation. The PubMed database was searched for articles about humans with total talar dislocation published in the English language in the last twenty years. The following data were entered into a Microsoft Excel spreadsheet: type of dislocation, nature of associated fractures (if any), type of reduction/fixation utilized, immobilization, weight‐bearing status, outcome, complications and average follow‐up time. Thirty‐nine articles reporting a total of 86 cases of total talar dislocation are included in this review. Seventy‐three of these were open injuries and 13 closed. Forty‐three cases had an associated foot or ankle fracture, 32 of those cases specifically having a fracture of the talus. The talus was preserved in the initial management of 74 cases, whereas the remaining 12 cases were managed by primary talectomy. The mean duration of follow‐up was 32 months. Twenty‐two cases required a secondary arthrodesis or another additional procedure. A good outcome was achieved in 35% of cases, a fair outcome in 37% and a poor outcome in 27%. The complication of avascular necrosis (AVN) occurred in 22 cases and 14 subjects developed clinically significant osteoarthritis. Generally, the outcome of current treatments associated with total talar dislocation is not ideal, only 1/3 of cases achieving good outcomes. So far, preservation of the talus is the best treatment option. AVN is still a relatively common complication even in the absence of fracture or postoperative infection.