Cost-Benefit Analysis of Tafenoquine for Radical Cure of Plasmodium vivax Malaria in Korea.

BACKGROUND: Plasmodium vivax malaria has a persistent liver stage that causes relapse, and introducing tafenoquine to suppress relapse could aid in disease eradication. Therefore, we assessed the impact of tafenoquine introduction on P. vivax malaria incidence and performed a cost-benefit analysis from the payer's perspective. METHODS: We expanded the previously developed P. vivax malaria dynamic transmission model and calibrated it to weekly civilian malaria incidences in 2014-2018. Primaquine and tafenoquine scenarios were considered by assuming different relapse probabilities, and relapse and total P. vivax malaria cases were predicted over the next decade for each scenario. We then estimated the number of cases prevented by replacing primaquine with tafenoquine. The cost and benefit of introducing tafenoquine were obtained using medical expenditure from a nationwide database, and a cost-benefit analysis was conducted. A probabilistic sensitivity analysis was performed to assess the economic feasibility robustness of tafenoquine introduction under uncertainties of model parameters, costs, and benefits. RESULTS: Under 0.04 primaquine relapse probability, the introduction of tafenoquine with relapse probability of 0.01 prevented 129 (12.27%) and 35 (77.78%) total and relapse cases, respectively, over the next decade. However, under the same relapse probability as primaquine, introducing tafenoquine had no additional preventative effect. The 14-day primaquine treatment cost was $3.71. The tafenoquine and the glucose-6-phosphate dehydrogenase rapid diagnostic testing cost $57.37 and $7.76, totaling $65.13. The average medical expenditure per malaria patient was estimated at $1444.79. The cost-benefit analysis results provided an incremental benefit-cost ratio (IBCR) from 0 to 3.21 as the tafenoquine relapse probability decreased from 0.04 to 0.01. The probabilistic sensitivity analysis showed an IBCR > 1, indicating that tafenoquine is beneficial, with a probability of 69.1%. CONCLUSION: Tafenoquine could reduce P. vivax malaria incidence and medical costs and bring greater benefits than primaquine.

Electrochemical Gene Amplification Signal Detection of Disposable Biochips Using Electrodes.

Real-time Polymerase Chain Reaction (RT-PCR), a molecular diagnostic technology, is spotlighted as one of the quickest and fastest diagnostic methods for the actual coronavirus (SARS-CoV-2). However, the fluorescent label-based technology of the RT-PCR technique requires expensive equipment and a sample pretreatment process for analysis. Therefore, this paper proposes a biochip based on Electrochemical Impedance Spectroscopy (EIS). In this paper, it was possible to see the change according to the concentration by measuring the impedance with a chip made of two electrodes with different shapes of sample DNA.

Hematologic Expression After Shoulder Surgery: Normalization Curve of Serum Inflammatory Markers.

PURPOSE: To determine the normalization curves of the serologic markers including white blood cell (WBC) count, WBC differential for segmented neutrophil (WBC seg.), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) after elective shoulder surgery and to investigate the hematologic differences among different shoulder surgeries. METHODS: Seventy-seven patients underwent arthroscopic rotator cuff repair (RCR, group A), 44 patients had open rotator cuff repair (group B), and 84 patients had shoulder arthroplasty (group C). Peak and normalization times of markers were determined at preoperatively, postoperative day (POD) 1 and 2 days, 1 and 2 weeks, 1, 2, 3, 6 months, and 1 year after surgery. The normal ranges of serologic markers were set to WBC 4000 to10,000/µL, WBC seg. 40% to 60%, ESR 0 to 20 mm/h, and CRP 0 to 0.8 mg/dL. RESULTS: Groups reached peak mean WBC count and WBC seg. on POD 1; mean WBC count started decreasing on POD 2 but was within normal value afterwards. Mean WBC seg. decreased to normal value at 1 month postoperatively in group A and B and at 2 months postoperatively in group C. Mean ESR peaked at 2 weeks postoperatively and normalized after 1 month in groups A and B and 3 months in group C. Mean CRP levels peaked on POD 2 in all groups and normalized within 2 weeks postoperatively in groups A and B and 1 month postoperatively in Group C. Normalized values of WBC count, WBC seg., and ESR varied widely. In contrast, CRP showed a consistent undetectable median, upper and lower quartile values less than 0.5 after normalization. Mean serum ESR and CRP values at peak time were significantly greater in group C than in the other groups (P = .001). CONCLUSIONS: The mean CRP levels were normalized at 2 weeks after rotator cuff repair and at 1 month after arthroplasties. Unlike the other serologic markers, CRP had consistent normalized values of median, upper and lower quartile afterwards. The peak levels of the inflammatory markers were greater and therefore normalized slower following more invasive surgery. LEVEL OF EVIDENCE: Level III, case control study.

Quantitative Analysis of Fluorescence Detection Using a Smartphone Camera for a PCR Chip.

Most existing commercial real-time polymerase chain reaction (RT-PCR) instruments are bulky because they contain expensive fluorescent detection sensors or complex optical structures. In this paper, we propose an RT-PCR system using a camera module for smartphones that is an ultra small, high-performance and low-cost sensor for fluorescence detection. The proposed system provides stable DNA amplification. A quantitative analysis of fluorescence intensity changes shows the camera's performance compared with that of commercial instruments. Changes in the performance between the experiments and the sets were also observed based on the threshold cycle values in a commercial RT-PCR system. The overall difference in the measured threshold cycles between the commercial system and the proposed camera was only 0.76 cycles, verifying the performance of the proposed system. The set calibration even reduced the difference to 0.41 cycles, which was less than the experimental variation in the commercial system, and there was no difference in performance.

Open Platform Cameras Based Bio-Imaging Evaluation System.

With the active development of mobile devices, a variety of ultra-small, high-definition, and open platform-based cameras are being mass-produced. In this paper, we established an emulation system to verify the bio-imaging performance of the bulky and expensive high-performance cameras and various smartphone cameras that have been used in bio-imaging devices. In the proposed system, the linearity of the brightness gradient change of four types of cameras was compared and analyzed. Based on these results, three cameras were selected in order of excellent linearity, and gel image analysis results were compared.

Cost-Effective Multiplex Fluorescence Detection System for PCR Chip.

The lack of portability and high cost of multiplex real-time PCR systems limits the device to be used in POC. To overcome this issue, this paper proposes a compact and cost-effective fluorescence detection system that can be integrated to a multiplex real-time PCR equipment. An open platform camera with embedded lens was used instead of photodiodes or an industrial camera. A compact filter wheel using a sliding tape is integrated, and the excitation LEDs are fixed at a 45° angle near the PCR chip, eliminating the need of additional filter wheels. The results show precise positioning of the filter wheel with an error less than 20 µm. Fluorescence detection results using a reference dye and standard DNA amplification showed comparable performance to that of the photodiode system.

Cloud-Based Software Architecture for Fully Automated Point-of-Care Molecular Diagnostic Device.

This paper proposes a cloud-based software architecture for fully automated point-of-care molecular diagnostic devices. The target system operates a cartridge consisting of an extraction body for DNA extraction and a PCR chip for amplification and fluorescence detection. To facilitate control and monitoring via the cloud, a socket server was employed for fundamental molecular diagnostic functions such as DNA extraction, amplification, and fluorescence detection. The user interface for experimental control and monitoring was constructed with the RESTful application programming interface, allowing access from the terminal device, edge, and cloud. Furthermore, it can also be accessed through any web-based user interface on smart computing devices such as smart phones or tablets. An emulator with the proposed software architecture was fabricated to validate successful operation.

Multiple Compact Camera Fluorescence Detector for Real-Time PCR Devices.

The polymerase chain reaction is an important technique in biological research because it tests for diseases with a small amount of DNA. However, this process is time consuming and can lead to sample contamination. Recently, real-time PCR techniques have emerged which make it possible to monitor the amplification process for each cycle in real time. Existing camera-based systems that measure fluorescence after DNA amplification simultaneously process fluorescence excitation and emission for dozens of tubes. Therefore, there is a limit to the size, cost, and assembly of the optical element. In recent years, imaging devices for high-performance, open platforms have benefitted from significant innovations. In this paper, we propose a fluorescence detector for real-time PCR devices using an open platform camera. This system can reduce the cost, and can be miniaturized. To simplify the optical system, four low-cost, compact cameras were used. In addition, the field of view of the entire tube was minimized by dividing it into quadrants. An effective image processing method was used to compensate for the reduction in the signal-to-noise ratio. Using a reference fluorescence material, it was confirmed that the proposed system enables stable fluorescence detection according to the amount of DNA.

Difficulty in performing activities of daily living associated with internal rotation after reverse total shoulder arthroplasty.

BACKGROUND: Reverse total shoulder arthroplasty (RSA) is a widely accepted treatment for irreparable massive rotator cuff tear (mRCT) and cuff tear arthropathy (CTA), but its impact on activities of daily living (ADLs) remains unclear. METHODS: We retrospectively analyzed 77 patients (age range, 54-87 years; follow-up range, 36.1-120.3 months) with irreparable mRCT and CTA treated by medialized RSA between 2008 and 2015. Ten activities considered essential for daily living were selected and scored from 0 to 3. RESULTS: The mean visual analog scale scores during motion and University of California at Los Angeles and Constant scores significantly improved at final follow-up (all P < .001). Active forward flexion, external rotation at the side, and internal rotation to the posterior (IRp) were 92.5%, 79.6%, and 48.4% of the contralateral side, respectively, at final follow-up. Active forward flexion and external rotation at the side recovered within 6 months after surgery, similar to the level at final follow-up, but IRp did not reach the preoperative status until final follow-up. ADLs with mean scores of less than 2.0 at final follow-up were "wash the opposite shoulder," "wash the opposite axilla," "use a back pocket," "manage the toilet," and "wash the back" (only 36.4% of patients were able to wash their back at final follow-up). CONCLUSIONS: RSA for irreparable mRCT and CTA showed satisfactory clinical outcomes. However, IRp was associated with a limited range compared with the other shoulder motions; therefore, all ADLs associated with internal rotation demonstrated lower recovery rates than expected.

Arthroscopic Findings and Clinical Outcomes in Patients 40 Years of Age and Older With Recurrent Shoulder Dislocation.

PURPOSE: The present study investigates the intra-articular findings and clinical outcomes after arthroscopic surgery in patients after age 40 with chronic anterior shoulder instability. METHODS: Fifty patients older than 40 years who underwent arthroscopic stabilization for recurrent anterior shoulder dislocation were analyzed. RESULTS: The mean age at the time of surgery was 44.8 years (range, 40-72 years), and the mean duration of follow-up was 45 months (range, 28-150 months). The mean visual analog scale score for pain with motion significantly improved from 4.1 preoperatively to 1.7 at the last follow-up (P < .001). The range of motion in the affected shoulder revealed limitations of 9.4° in forward flexion and 17.8° in external rotation compared with the unaffected shoulder. Both the Constant and Rowe scores significantly improved (P < .001 and P < .001, respectively). Recurrence, which includes dislocation and subluxation, occurred in 14% postoperatively. Anteroinferior labral lesion was seen in 92% of patients. Associated lesions included superior labrum anterior to posterior lesion (22%), midsubstance capsular tear (10%), and Hill-Sachs lesion (92%). Rotator cuff tears were found in 18%-partial-thickness tear in 10% and full-thickness tear, which was repaired with suture anchor, in 8%. Among the intra-articular lesions, there was no significant relation with recurrent instability or functional outcome as a single factor. CONCLUSIONS: In patients with chronic anterior shoulder instability who were older than 40 years, the clinical results after arthroscopic surgery showed statistically significant improvement with good muscle strength recovery. The quality of labral lesion, size of the Hill-Sachs lesion, and glenoid defect showed positive correlation with the number of preoperative dislocation. The intra-articular pathologies were varied, however no single articular lesion had significant impact on the recurrence rate. LEVEL OF EVIDENCE: Level IV, case series.

Arthroscopic Side-to-side Repair for Large U-shaped Full-Thickness Rotator Cuff Tears: Is the Repair Integrity Actually Maintained?

PURPOSE: To evaluate the clinical and structural outcomes of arthroscopic side-to-side repair of large U-shaped full-thickness rotator cuff tears (FTRCTs) by assessing the functional score of the patients and the integrity of the tendon repair using magnetic resonance imaging with a minimum follow-up duration of 2 years. METHODS: In this case series, 59 consecutive patients who underwent arthroscopic side-to-side repair of large U-shaped FTRCTs, with a minimum follow-up duration of 2 years (range 25 to 72 months), were retrospectively enrolled. The mean patient age was 58.6 years. Patients' functional scores and integrity of the tendon repairs were evaluated. RESULTS: The mean visual analog scale score improved from 5.7 ± 2.1 preoperatively to 2.4 ± 1.3 postoperatively (P < .001). The mean range of motion (forward flexion) improved from 152.7° ± 11.4° to 164.5° ± 9.5° (P < .001). The mean Constant-Murley score improved from 57.3 ± 7.2 preoperatively to 77.8 ± 6.9 postoperatively (P < .001). Postoperative magnetic resonance imaging examinations demonstrated cuff integrity with a retear rate of 54.2%. The retear rate of patients who underwent anchor fixation to the medial row (45%) was significantly lower than that of patients who underwent simple side-to-side repair (73.7%) (P = .039). The University of California at Los Angeles shoulder rating and Constant-Murley scores were not significantly different between the healed and retear groups (P = .639 and P = .863, respectively). CONCLUSIONS: Arthroscopic side-to-side repair of large U-shaped FTRCTs demonstrated satisfactory clinical outcomes. However, the retear rate was higher than expected when simple side-to-side fixation was performed without footprint fixation. Therefore, medial row fixation is recommended if arthroscopic side-to-side repair is performed. LEVEL OF EVIDENCE: III, comparative therapeutic trial.

Rapidly destructive arthropathy of shoulder joint.

BACKGROUND: Rapidly destructive arthropathy (RDA) of the shoulder is rare. Consequently, there are very few studies that have reported the characteristic findings of this disease. This study aimed to analyze the clinical, radiographic, and histologic features of patients with RDA of the shoulder. METHODS: In total, 9 cases (8 patients) were enrolled in this study. All patients were elderly women, with a mean age of 72.7 years (range, 57-78 years). The mean duration of symptoms was 4.1 months (range, 1.2-5.9 months). Reverse total shoulder arthroplasty and total shoulder arthroplasty were performed in 5 cases with massive rotator cuff tears and 4 without them, respectively. RESULTS: The mean duration of radiologically evident joint destruction after negative results on radiography was 3.1 months (range, 1.0-5.9 months). On plain radiography, humeral head flattening and collapse that appeared like cut grass were observed (100%). Relatively good preservation of the glenoid with a normal joint space was observed in 7 cases, whereas glenoid erosion was observed in 2 (22.2%). T1-weighted magnetic resonance imaging showed a subchondral fracture (100%) of low signal intensity with associated bone marrow edema. Histologically, chronic inflammation of the synovium and osteocytes in the lacunae, as well as callus formation, were observed along the subchondral fracture. CONCLUSION: Flattening and collapse of the humeral head within an average of 4 months of symptom onset are characteristic of RDA of the shoulder. Bone marrow edema, joint effusion, and subchondral fracture on magnetic resonance imaging and fracture fragments and callus formation on histopathologic analysis were observed. Glenoid erosion was observed in 2 cases with arthrosis progression.

Hematologic profile in reverse total shoulder arthroplasty: perioperative and postoperative blood loss.

BACKGROUND: Few studies have investigated the amount of blood loss during reverse total shoulder arthroplasty (RTSA). The purpose of this study was to investigate blood loss in patients who underwent RTSA for massive irreparable rotator cuff tear (MIRCT) using the hemoglobin (Hb) balance method and total Hemovac amount and to identify predictors of blood transfusion in these patients. METHODS: We retrospectively reviewed 121 patients who underwent RTSA for MIRCT. The mean age was 71.2 ± 6.9 years, and 75 were women. Age, sex, body mass index, use of anticoagulants, American Society of Anesthesiologists physical status score, comorbidities (eg, hypertension, diabetes mellitus, cerebrovascular accident), preoperative Hb level, preoperative hematocrit level, preoperative prothrombin time/international normalized ratio, use of cement, and operative time were evaluated as values predicting blood transfusion. RESULTS: The overall blood loss was 846.6 ± 527.6 mL, which included 346 ± 231.2 mL of intraoperative blood loss and 500.3 ± 196.4 mL of postoperative blood loss. Values predicting blood transfusion were a lower preoperative Hb level (P < .001), hematocrit level (P < .001), hypertension (P = .018), and cerebrovascular accident (P = .008). Receiver operating characteristic analysis identified the following cutoff values for predicting transfusion: preoperative Hb level of 13.5 g/dL (90.3% sensitivity) and hematocrit of 40% (90.3% sensitivity). CONCLUSIONS: RTSA for MIRCT is associated with blood loss during and after surgery. The amount of blood loss should be noted, and blood transfusion could be predicted by calculating the blood loss and predictive values. Lower preoperative Hb level, hematocrit, hypertension, and cerebrovascular accident are predictors of blood transfusion. Blood transfusion should be considered if a patient with preoperative Hb level <13.5 g/dL and hematocrit <40% has a history of hypertension or cerebrovascular accident.

Comparison of named entity recognition methodologies in biomedical documents.

BACKGROUND: Biomedical named entity recognition (Bio-NER) is a fundamental task in handling biomedical text terms, such as RNA, protein, cell type, cell line, and DNA. Bio-NER is one of the most elementary and core tasks in biomedical knowledge discovery from texts. The system described here is developed by using the BioNLP/NLPBA 2004 shared task. Experiments are conducted on a training and evaluation set provided by the task organizers. RESULTS: Our results show that, compared with a baseline having a 70.09% F1 score, the RNN Jordan- and Elman-type algorithms have F1 scores of approximately 60.53% and 58.80%, respectively. When we use CRF as a machine learning algorithm, CCA, GloVe, and Word2Vec have F1 scores of 72.73%, 72.74%, and 72.82%, respectively. CONCLUSIONS: By using the word embedding constructed through the unsupervised learning, the time and cost required to construct the learning data can be saved.

Best serum biomarker combination for ovarian cancer classification.

BACKGROUND: Screening test using CA-125 is the most common test for detecting ovarian cancer. However, the level of CA-125 is diverse by variable condition other than ovarian cancer. It has led to misdiagnosis of ovarian cancer. METHODS: In this paper, we explore the 16 serum biomarker for finding alternative biomarker combination to reduce misdiagnosis. For experiment, we use the serum samples that contain 101 cancer and 92 healthy samples. We perform two major tasks: Marker selection and Classification. For optimal marker selection, we use genetic algorithm, random forest, T-test and logistic regression. For classification, we compare linear discriminative analysis, K-nearest neighbor and logistic regression. RESULTS: The final results show that the logistic regression gives high performance for both tasks, and HE4-ELISA, PDGF-AA, Prolactin, TTR is the best biomarker combination for detecting ovarian cancer. CONCLUSIONS: We find the combination which contains TTR and Prolactin gives high performance for cancer detection. Early detection of ovarian cancer can reduce high mortality rates. Finding a combination of multiple biomarkers for diagnostic tests with high sensitivity and specificity is very important.

A method of inferring the relationship between Biomedical entities through correlation analysis on text.

BACKGROUND: One of the most important processes in a machine learning-based natural language processing is to represent words. The one-hot representation that has been commonly used has a large size of vector and assumes that the features that make up the vector are independent of each other. On the other hand, it is known that word embedding has a great effect in estimating the similarity between words because it expresses the meaning of the word well. In this study, we try to clarify the correlation between various terms in the biomedical texts based on the excellent ability of estimating similarity between words shown by word embedding. Therefore, we used word embedding to find new biomarkers and microorganisms related to a specific diseases. METHODS: In this study, we try to analyze the correlation between diseases-markers and diseases-microorganisms. First, we need to construct a corpus that seems to be related to them. To do this, we extract the titles and abstracts from the biomedical texts on the PubMed site. Second, we express diseases, markers, and microorganisms' terms in word embedding using Canonical Correlation Analysis (CCA). CCA is a statistical based methodology that has a very good performance on vector dimension reduction. Finally, we tried to estimate the relationship between diseases-markers pairs and diseases-microorganisms pairs by measuring their similarity. RESULTS: In the experiment, we tried to confirm the correlation derived through word embedding using Google Scholar search results. Of the top 20 highly correlated disease-marker pairs, about 85% of the pairs have actually undergone a lot of research as a result of Google Scholars search. Conversely, for 85% of the 20 pairs with the lowest correlation, we could not actually find any other study to determine the relationship between the disease and the marker. This trend was similar for disease-microbe pairs. CONCLUSIONS: The correlation between diseases and markers and diseases and microorganisms calculated through word embedding reflects actual research trends. If the word-embedding correlation is high, but there are not many published actual studies, additional research can be proposed for the pair.

Permanent magnet actuation for magnetic bead-based DNA extraction.

BACKGROUND: Recently, automatic molecular diagnostic devices to extract DNA have been extensively developed using magnetic beads. While various methods can be applied to the control of the beads, the efficiency of the control when incorporated in automatic devices has not been studied. This paper proposes a compact magnet actuation method for the control of magnetic beads for DNA extraction, and compares the efficiency to the already available magnetic bead-based DNA extraction device. A permanent magnet was preferred for its compactness, while an electro-magnet provides easy operation. After investigating various methods to actuate the magnet with perspective to the size, circuit complexity, and power requirement, we determined the solenoid actuation method to be most efficient. To further reduce the dimension of the overall actuation device, direct actuation of the permanent magnet to control the hold/release of the beads was employed in this paper. The proposed method was compared with the conventional solenoid actuator with a metal plunger. An experimental fluidics device was set up with a fluidic channel and a syringe pump. The bead holding performance against the fluid speed was tested while a fixed amount of beads was loaded into the center of the channel. The group velocity of the beads was analyzed via image processing to determine whether the magnet was sufficient to hold the beads. The required power and space was analyzed and compared qualitatively and quantitatively. RESULT: The proposed direct actuation method was capable of holding the beads at faster fluidic speed than the conventional solenoid actuator. The required power was comparable contemplating the high initial power of the solenoid actuator, and required much smaller space since no plunger was needed. CONCLUSIONS: The direct actuation of the permanent magnet using a solenoid coil showed enhanced performance in holding the beads via permanent magnet, with less complexity of the actuation circuit and space. The proposed method therefore can efficiently improve the overall performance of the bead-based DNA extraction.

Performance evaluation of optimal real-time polymerase chain reaction achieved with reduced voltage.

BACKGROUND: Polymerase chain reaction (PCR) is used in nucleic acid tests of infectious diseases in point-of-care testing. Previous studies have demonstrated real-time PCR that uses a micro-PCR chip made of packing tape, double-sided tape, and a plastic cover with polycarbonate or polypropylene on a black matte printed circuit board substrate. Despite the success of DNA amplification and fluorescence detection using an early version of the micro-PCR chip, reaching the target temperature was fairly slow and, as a result, the total running time was getting longer. To reduce this runtime, the micro-PCR chip was modified by reducing the heater pattern size of the PCB substrate to one-quarter of the original size or less, while maintaining the ability of the heating pattern to cover the reservoir area of the microfluidic channel. In subsequent experiments, DNA amplification failed several times. During the analysis of the cause of this failure, it was found that the reagent was boiling with the heating range from 25 to 95 °C. METHODS: As a method of DNA amplification verification, images were captured by digital single-lens reflex camera to detect FAM fluorescence using diagonal illumination from a blue LED light source. The images were automatically captured at 72 °C (the extension step in nucleic acid amplification) and the brightness of the captured images was analyzed to con-firm the success of DNA amplification. RESULTS: Compared to the previous chip with a larger heating pattern size, the current chip appears to generate excess energy as the size of the heating pattern was reduced. To reduce this excess energy, the initial voltage was lowered to 2 V and 2.5 V, which is equivalent to a one-fifth and one-quarter voltage-power reduction in pulse width modulation control, respectively. In both voltage reduction cases, the DNA amplification was successful. CONCLUSIONS: DNA amplification tests may fail due to the excess energy generated by reducing the heater pattern size of the PCB substrate. However, the tests succeeded when the voltage was reduced to 2 V or 2.5 V. The 2.5 V power test was more efficient for reducing the overall running time.

Evaluation-independent system for DNA section amplification.

BACKGROUND: In general, the image analysis of nucleic acid for detecting DNA is dependent on the gel documentation system. These experiments may deal with harmful staining agents and are time consuming. To address these issues, real-time polymerase chain reaction (PCR) devices have been developed. The advantages of real-time PCR are its capabilities for real-time diagnosis, improved sensitivity, and digitization of measurement results. However, real-time PCR equipment is still too bulky and expensive for use in small hospitals and laboratories. METHODS: This paper describes an evaluation-independent real-time PCR system that differs from conventional systems in that it uses a side-illumination optical detection system and a temperature adjustment coefficient for DNA detection. The overall configuration of the evaluation-independent system includes the PCR chip and system hardware and software. The use of the side-illumination method for detection enables the system size to be reduced compared to systems using a typical illumination method. Furthermore, the results of a PCR test are strongly affected by the reaction temperature. Thus, extremely precise control of the temperature of the reaction is needed to obtain accurate results and good reliability. We derived a temperature compensation coefficient that allows us to compensate for the differences between the measured temperature of the negative temperature coefficient (NTC) thermistor sensor and the real temperature of the thermocouple. RESULTS: Applying the temperature compensation coefficient parameter using the NTC thermistor and using the side-illumination method resulted in an increase in the initial sensor value. The occurrence of the DNA section amplification decreased to 22 cycles from 24 cycles. CONCLUSIONS: The proposed system showed comparable performance to that of an existing real-time PCR, even with the use of simpler and smaller optical devices.

A study of polymerase chain reaction device control via cloud using Firebase Cloud Messaging protocol.

BACKGROUND: In this paper, we propose a system for data monitoring and control of polymerase chain reaction (PCR) externally. PCR is a technique for amplifying a desired DNA molecule by repeatedly synthesizing a specific part of DNA sequence. Currently, commercially available systems are standalone systems or operate PCR devices through a computer in the vicinity of devices for control purposes. These systems are limited in the number of devices that the host system can monitor at the same time, and there are limitations in controlling devices or accessing experimental data externally. Therefore, we propose a system to control the PCR device via the cloud for the convenience of the user and to overcome the limitation of the place. METHODS: The cloud system used in this study is Google's Firebase. At this time, we use Firebase Cloud Messaging (FCM) protocol to send and receive data. In this paper, we have experimented on the possibility of data transmission and reception using FCM between device, cloud and user. Since the PCR chips used in the research are generally operated at about 10°/s, and the temperature can be controlled within 0.5°, the processing period of the control process should be made much smaller than 1/20 s (50 ms). RESULTS: As a result of experiments, the time of the data round-trip using FCM was measured at 150 ms on the average. Therefore, the data exchange time using FCM is three times slower than the reference time of 50 ms. CONCLUSIONS: Since the data round-trip time using FCM is measured to be three times slower than the reference time of 50 ms, it is impossible for the user to control the device such as the PCR device used in this study through the cloud. However, it is possible for the user to monitor the status of the PCR device from the outside in real time.