While there are not any effective antidotes for paraquat poisoning up to this time, several procedures such as gastric lavage, dosing of emetics and adsorbents, hemodialysis, peritoneal dialysis and hemoperfusion have been applied in treatment of paraquat intoxication.
In this study, we determined efficacy of the combined application of oral administration of an adsorbent (Adsorbin) and hemoperfusion using activated charcoal (HEMOSORBA: activated charcoal coated collodion, The ASAHI Medical Co.) in dogs being given orally paraquat in the amount of 40 mg per kg of the body weight.
Efficacy of the treatments was in order of the combined application of dosing Adsorbin and the hemoperfusion with Hemosorba, single use of dosing Adsorbin and single application of the hemoperfusion.
Oral administration of the adsorbent was carried out only once, either one hour or three hours after forced dosing of paraquat, and the hemoperfusion was started either one or three hours after paraquat dosing and continued for six hours in each case.
Effectiveness of the treatment on the survival-time was superior in the case of dosing the adsorbent and starting the hemoperfusion one hour after paraquat administration.
As a sign of developing lung fibrosis was found on histopathological observation in dogs survived for twenty days after starting the experiment, even in case of the combined treatment with the best results, observation of longer period seems to be necessary for obtaining more information after treatment. And it is furthermore advisable that the treatment, especially the hemoperfusion, should be continued or carried out more than one time until the concentration of paraquat in blood plasma decreases to the safe level.

There have been hardly any cases of paraquat poisoning during normal use of paraquat as a herbicide, but there have been a number of deaths or cases of serious poisoning due to ingestion of paraquat products as the result of suicidal intent or accidents, and the survival rate is extremely low. To prevent the occurrence of paraquat poisoning, some experiments have been conducted in which emetics were added to paraquat products.
In this study, we determined the efficacy of including Triazolopyrimidine compound (pp) as an emetic in a paraquat product, when it was orally administered to dogs under the starved (condition A) or unstarved (condition B) conditions. When paraquat was orally given to the dogs (40 mg/kg body weight) under condition A, emesis occured four to six hours after the dosing. However, in the case of giving a dose of the mixed solution of paraquat and pp (PQ 40mg/kg, pp 2mg/kg), vomiting took place after four to six minutes (vomited rate of PQ: 86.4%) and seven to twenty minutes (vomited rate of PQ: 61.2%) under conditions A and B respectively. The average survival period in the case of the paraquat dosing was fifteen days and six days under conditions A and B respectively. However, in the case of giving a dose of the mixed solution of paraquat and pp, it was more than 20 days and 12.7 days under conditions A and B respectively.
The results of the experiment suggest that the inclusion of emetics is one of the effective means of preventing paraquat poisoning. As the amount of ingested paraquat is usually large in the case of suicidal intention, it is conceivable that an amount greater than the lethal dose will remain in the gastrointestinal system even if the emetic included in the paraquat produces vomiting in patients. Since the inclusion of emetics in paraquat products leads to an early occurrence of vomiting in the victim, the chances of finding him or her earlier should be increased. This would, in turn, make earlier treatment possible.

The exposure levels of nine spray-operators in apple orchards to Fenitrothion (MEP) was measured. The pesticide was sprayed in the form of a 1, 000-fold diluted solution of a 40% MEP wettable powder by using power sprayers.
The operators were wearing protective non-woven clothes, masks (Sumitomo 3M 1780) and rubber gloves.
The estimated exposure amount of MEP per operator was 217mg on average when a sprayer with a short rod (50-70 cm) was used. In the case of using a long rod (100-120 cm), the amount was less, indicating 44mg on average.
The estimated amount of MEP penetrating the operator's clothing was 7.6mg on average, ranging from 1.2 to 23.9mg.
The penetration rate averaged 6.3%.
We calculated the MEP concentration in the air around the worker's mouth estimated from the amounts of MEP on the masks and from those in the sampling columns. The results averaged 0.258 mg/m₃ and 0.022 mg/m₃, respectively.
MEP was detected in blood samples from all the operators (0.0004-0.0222 ppm) immediately after the spray work and in blood samples from four of the nine operators (0.0004-0.0009 ppm) after one day, but not detected in any of the nine blood samples after three days.
A decrease in blood ChE activities of the operators was not observed.
The amount of MEP absorbed into the operator's body was calculated to be 0.34 to 2.59 mg. These calculations were based on the amount of the metabolites (converted into nitro-m-cresol) in the urine samples collected from the operators over a period of 24 hours after the spray work. However, the metabolites were detected in the spot urine samples of only one of the nine operators after three days and in none of the spot samples after seven days.
These results show that a small amount of MEP was absorbed into the operator's body, suggesting that the spray-operator should not do the spray work day after day. However, from the point of view of the percutaneous and inhalation toxicity of MEP, we concluded that the sprayoperators were not affected by MEP exposure in this case.

Prosthetic grafts have been employed in a limited number of pediatric patients with peripheral vascular lesions. We treated an iatrogenic obstruction of bilateral external iliac arteries in a child. The patient was a six-year-old girl whose chief complaints were intermittent claudication, and lower limb pain when exposed to cold. She had a history of coarctation complex for which she had undergone repeated catheterizations by puncture of both femoral arteries in her infancy. At the age of four, two-stage operation was performed: resection of the coarctation and end-to-end anastomosis, and direct closure of ventricular septal defect. Angiography performed through the brachial artery demonstrated obstruction of the bilateral external iliac arteries. Both right and left femoral artery were visualized through the collateral artery from the ipsilateral internal iliac artery. Because she became afflicted with lower limb ischemia a revascularization procedure was indicated. A 6mm expanded polytetrafluoroethylene (ePTFE) bypass graft was implanted bilaterally between the internal iliac artery and the common femoral artery with end-to-side anastomosis. Ischemic symptoms disappeared postoperatively and MR-angiogram performed nine days after surgery also showed the patency of the graft. It is a great concern, however, that the length of the graft may become relatively shorter with the growth of the patient. It is also anticipated that the lower limbs may suffer relatively insufficient blood flow in the future.

Major bleeding associated with sagittal split ramus osteotomy (SSRO) involves vessels such as the inferior alveolar, facial, and maxillary arteries and veins, and the retromandibular vein (RMV). The present study aimed to clarify and classify the three-dimensional variations in RMV position and course direction in relation to the mandible. Specimens comprised a total of 15 scientific cadavers, and the relationship between RMV and the mandible lateral and posterior views was observed.We identified 3 patterns on the lateral view, the mean distance between the RMV and the posterior border of the ramus was 3.9 mm at the height of the lingula. A total of five course patterns were identified on the posterior view. In no course pattern, the RMV inferior to the lingula was lateral to its position superior to the lingual. The present findings suggest that it may be possible to predict correlations with intraoperative bleeding risk. Further study is planned using contrast computed tomography in patients with jaw deformity for skeletal classification.

Background: Excessive bleeding is a major intraoperative risk associated with orthognathic surgery. This study aimed to investigate the factors involved in massive bleeding during orthognathic surgeries so that safe surgeries can be performed. Patients (n=213) diagnosed with jaw deformities and treated with bimaxillary orthognathic surgery (Le Fort I osteotomy and bilateral sagittal split ramus osteotomy) in the Department of Oral and Maxillofacial Surgery at the Suidobashi Hospital, Tokyo Dental College between January 2014 and December 2016 were included. Using the patients’ medical and operative records, the number of cases according to sex, age at the time of surgery, body mass index (BMI), circulating blood volume, diagnosis of maxillary deformity, direction of maxillary movement, operative duration, incidence of bad split, injury of nasal mucosa, and blood type were analyzed. Results: The results revealed that BMI, circulating blood volume, nasal mucosal injury, and operative time were associated with the risk of intraoperative massive bleeding in orthognathic surgeries. Chi-square tests and binomial logistic regression analyses showed significant differences in BMI, circulating blood volume, direction of maxillary movement, operative duration, and injury to the nasal mucosa. Operative duration emerged as the most important risk factor. Furthermore, a >4-mm upward migration of the posterior nasal spine predicted the risk of massive bleeding in orthognathic surgery. Conclusions The upward movement of the maxilla should be recognized during the preoperative planning stage as a risk factor for intraoperative bleeding, and avoiding damage to the nasal mucosa should be considered a requirement for surgeons to prevent massive bleeding during surgery.

BACKGROUND: Along with the advances in technology of three-dimensional (3D) printer, it became a possible to make more precise patient-specific 3D model in the various fields including oral and maxillofacial surgery. When creating 3D models of the mandible and maxilla, it is easier to make a single unit with a fused temporomandibular joint, though this results in poor operability of the model. However, while models created with a separate mandible and maxilla have operability, it can be difficult to fully restore the position of the condylar after simulation. The purpose of this study is to introduce and asses the novel condylar repositioning method in 3D model preoperational simulation. METHODS: Our novel condylar repositioning method is simple to apply two irregularities in 3D models. Three oral surgeons measured and evaluated one linear distance and two angles in 3D models. RESULTS: This study included two patients who underwent sagittal split ramus osteotomy (SSRO) and two benign tumor patients who underwent segmental mandibulectomy and immediate reconstruction. For each SSRO case, the mandibular condyles were designed to be convex and the glenoid cavities were designed to be concave. For the benign tumor cases, the margins on the resection side, including the joint portions, were designed to be convex, and the resection margin was designed to be concave. The distance from the mandibular ramus to the tip of the maxillary canine, the angle created by joining the inferior edge of the orbit to the tip of the maxillary canine and the ramus, the angle created by the lines from the base of the mentum to the endpoint of the condyle, and the angle between the most lateral point of the condyle and the most medial point of the condyle were measured before and after simulations. Near-complete matches were observed for all items measured before and after model simulations of surgery in all jaw deformity and reconstruction cases. CONCLUSIONS: We demonstrated that 3D models manufactured using our method can be applied to simulations and fully restore the position of the condyle without the need for special devices.
Chin ; Congenital Abnormalities ; Equidae ; Glenoid Cavity ; Humans ; Jaw ; Joints ; Mandible ; Mandibular Condyle ; Mandibular Osteotomy ; Maxilla ; Methods ; Oral and Maxillofacial Surgeons ; Orbit ; Orthognathic Surgery ; Osteotomy, Sagittal Split Ramus ; Surgery, Oral ; Temporomandibular Joint

Background: Mesiodentes are the most common supernumerary teeth. The cause is not fully understood, although proliferations of genetic factors and the dental lamina have been implicated. Mesiodentes can cause delayed or ectopic eruption of permanent incisors, which can further alter occlusion and appearance. Careful attention should be paid to the position and direction of the mesiodentes because of possible damage to adjacent roots in the permanent dentition period, errant extraction in the deciduous and mixed dentition periods, and damage to the permanent tooth embryo. To avoid these complications, we applied mixed reality (MR) technology using the HoloLens® (Microsoft, California). In this study, we report on three cases of mesiodentes extraction under general anesthesia using MR technology. Results: The patients ranged in age from 6 to 11 years, all three were boys, and the direction of eruption was inverted in all cases. The extraction approach was palatal in two cases and labial in one case. The average operative time was 32 min, and bleeding was minimal in all cases. No intraoperative or postoperative complications occurred. An image was shared preoperatively with all the surgeons using an actual situation model. Three surgeons used Microsoft HoloLens® during surgery, shared MR, and operated while superimposing the application image in the surgical field. Conclusions The procedure was performed safely; further development of MR surgery support systems in the future is suggested.