Rapid fiber-detection technique by artificial intelligence in phase-contrast microscope images of simulated atmospheric samples.

Since the manufacture, import, and use of asbestos products have been completely abolished in Japan, the main cause of asbestos emissions into the atmosphere is the demolition and removal of buildings built with asbestos-containing materials. To detect and correct asbestos emissions from inappropriate demolition and removal operations at an early stage, a rapid method to measure atmospheric asbestos fibers is required. The current rapid measurement method is a combination of short-term atmospheric sampling and phase-contrast microscopy counting. However, visual counting takes a considerable amount of time and is not sufficiently fast. Using artificial intelligence (AI) to analyze microscope images to detect fibers may greatly reduce the time required for counting. Therefore, in this study, we investigated the use of AI image analysis for detecting fibers in phase-contrast microscope images. A series of simulated atmospheric samples prepared from standard samples of amosite and chrysotile were observed using a phase-contrast microscope. Images were captured, and training datasets were created from the counting results of expert analysts. We adopted 2 types of AI models-an instance segmentation model, namely the mask region-based convolutional neural network (Mask R-CNN), and a semantic segmentation model, namely the multi-level aggregation network (MA-Net)-that were trained to detect asbestos fibers. The accuracy of fiber detection achieved with the Mask R-CNN model was 57% for recall and 46% for precision, whereas the accuracy achieved with the MA-Net model was 95% for recall and 91% for precision. Therefore, satisfactory results were obtained with the MA-Net model. The time required for fiber detection was less than 1 s per image in both AI models, which was faster than the time required for counting by an expert analyst.

Risk assessment of farmers handling pelleted seeds containing crystalline silica and attapulgite.

OBJECTIVES: This study aimed to assess the risk to farmers from handling pelleted seeds that include crystalline silica and attapulgite. METHODS: We measured personal exposure levels to respirable crystalline silica and attapulgite in the experimenter representing a farmer in a simulated workplace. From these values, the annual occupational exposure levels were estimated and compared with the established occupational exposure limits. To assess the toxicity of respirable crystalline silica and attapulgite, digital chest images of workers in a factory producing pelleted seeds were examined. RESULTS: The personal exposure measurement results showed that the concentrations of total dust, respirable dust, and respirable crystalline silica generated during work handling of pelleted seeds were 0.27, 0.06, and 0.00043 mg/m3 , respectively. The estimated annual occupational exposure level to total dust, respirable dust, and respirable crystalline silica in farmers was 103 to 104 times lower than established occupational exposure limits. Attapulgite was not detected by analysis of the pelleted seeds themselves or dust collected during the personal exposure measurements. No pulmonary parenchymal or pleural lesions were detected in the digital chest images of the factory workers. CONCLUSION: We found that farmers handling pelleted seeds would not be exposed to levels of total dust, respirable dust, respirable crystalline silica, and attapulgite derived from pelleted seeds exceeding occupational exposure limits. These results suggest that the risk to farmers of handling pelleted seeds is negligible.

Development of rapid and highly accurate method to measure concentration of fibers in atmosphere using artificial intelligence and scanning electron microscopy.

AIM: We aimed to develop a measurement method that can count fibers rapidly by scanning electron microscopy equipped with an artificial intelligence image recognition system (AI-SEM), detecting thin fibers which cannot be observed by a conventional phase contrast microscopy (PCM) method. METHODS: We created a simulation sampling filter of airborne fibers using water-filtered chrysotile (white asbestos). A total of 108 images was taken of the samples at a 5 kV accelerating voltage with 10 000X magnification scanning electron microscopy (SEM). Each of three expert analysts counted 108 images and created a model answer for fibers. We trained the artificial intelligence (AI) using 25 of the 108 images. After the training, the AI counted fibers in 108 images again. RESULTS: There was a 12.1% difference between the AI counting results and the model answer. At 10 000X magnification, AI-SEM can detect 87.9% of fibers with a diameter of 0.06-3 µm, which is similar to a skilled analyst. Fibers with a diameter of 0.2 µm or less cannot be confirmed by phase-contrast microscopy (PCM). When observing the same area in 300 images with 1500X magnification SEM-as listed in the Asbestos Monitoring Manual (Ministry of the Environment)-with 10 000X SEM, the expected analysis time required for the trained AI is 5 h, whereas the expected time required for observation by an analyst is 251 h. CONCLUSION: The AI-SEM can count thin fibers with higher accuracy and more quickly than conventional methods by PCM and SEM.

Ovarian teratoma development after anti-NMDA receptor encephalitis treatment.

BACKGROUND: Anti-NMDA-R receptor encephalitis occurs predominantly in younger women and is often comorbid with ovarian teratoma, a feature that is often absent in children. Here, we report our experience with two pediatric patients, in whom no tumors were present during treatment for encephalitis, but in whom ovarian teratomas developed without encephalitis relapse after treatment was completed. CASES: Patient 1 was a 14-year-old girl who was diagnosed due to characteristic symptoms and anti-NMDA-R antibody. MRI scanning during treatment revealed no ovarian tumors, but a tumor developed in the right ovary 10months after onset. Another tumor developed in the left ovary 3years after onset, and a mature ovarian teratoma was confirmed after bilateral partial ovariectomy. Patient 2 was an 11-year old girl who was also diagnosed due to characteristic symptoms and anti-NMDA-R antibody. Imaging during treatment revealed no ovarian tumors, but a 2.5-cm tumor mass was found in the left ovary 10months after onset, and a mature ovarian teratoma was confirmed after partial ovariectomy. DISCUSSION: This case report suggests the need for regular tumor screening after treatment for anti-NMDA receptor encephalitis because of potential subsequent tumor development, even in pediatric patients who initially present with no comorbid tumors. No analysis of relapse risk has yet been reported in cases of tumor development after treatment, and at this point, whether or not resection is needed to prevent relapse remains unclear. However, because teratomas usually grow, have an associated risk of torsion, and can be malignant, tumor removal should be considered.

Drugs indicated for mitochondrial dysfunction as treatments for acute encephalopathy with onset of febrile convulsive status epileptics.

We studied the efficacy of drugs indicated for mitochondrial dysfunction in the treatment of 21 patients with acute encephalopathy with onset of febrile convulsive status epilepticus at our hospital from January 2006 to December 2014. Among them, 11 patients had been treated with a mitochondrial drug cocktail consisting of vitamin B1, vitamin C, biotin, vitamin E, coenzyme Q10, and l-carnitine (prescription group) and 10 patients were not treated with the cocktail (non-prescription group). We retrospectively reviewed age, trigger, clinical form, treatment start time, and sequelae. Clinical form was classified into a biphasic group presenting acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) and a monophasic group. Sequelae were classified as (A) no sequelae group or (B) sequelae group, and differences in the interval between diagnosis and treatment were also evaluated. The sequelae were not different between the mitochondrial drug cocktail prescription and non-prescription groups, but significantly better in the group administered the mitochondrial drug cocktail within 24h (P=0.035). We expect that early treatment with a mitochondrial drug cocktail could prevent sequelae in acute encephalopathy with onset of febrile convulsive status epilepticus.

Acute scrotum in Kawasaki disease: two case reports and a literature review.

Acute scrotum is a rare complication of acute Kawasaki disease (KD), less well recognized than other disease manifestations. We describe the cases of two patients, aged 59 months and 19 months, with hydrocele testis in the acute phase of KD. Scrotal ultrasound and trans-illumination were used in the diagnosis of hydrocele testis. One patient underwent eventual surgical intervention. We reviewed the literature for a better understanding of the pathogenesis of scrotal symptoms in acute KD and investigated the clinical importance of hydrocele testis. Careful further clinical observation may elucidate the true incidence of this extracardiac symptoms, thereby clarifying the diagnostic value of this possible complication in acute KD.

Persistent median artery in the hand: a report with a brief review of the literature.

We encountered a persistent median artery in the forearms and hands bilaterally in a 78-year-old Japanese male cadaver during dissection practice at Wakayama Medical University. The brachial arteries divided into the ulnar and radial arteries. The ulnar artery gave off the median and posterior interosseous arteries at the same point, although the anterior interosseous artery was not found. The median artery ran along the median nerve and bifurcated in the hand. In the superficial layer of the palm, one branch of the median artery ran to the ulnar side of the thumb, whereas the other passed to the second interdigital space. The ulnar artery reached the third and fourth interdigital spaces and the ulnar side of the little finger, and showed no anastomosis with the median artery in the superficial layer of the palm. The radial artery did not give off the superficial palmar branch. Therefore, the formation of the superficial palmar arch was incomplete. In the deep layer of the palm, the radial artery formed the deep palmar arch with the deep palmar branch of the ulnar artery and gave off the princeps pollicis artery. In the dorsum of hand, the radial artery passed over the first dorsal interosseous muscle to the index finger and communicated with the palmar pollical artery from the median artery in the first interosseous space. The present study reports an unusual variation of the persistent median artery in the hand and briefly reviews the literature about the median artery.