Prone-Position Thoracoscopic Ligation of the Thoracic Duct for Chyle Leak Following Radical Neck Dissection in a Patient with a Right Aortic Arch

A chyle leak can occur as a complication after neck or chest surgery. Such a leak prolongs the hospital stay and is sometimes life-threatening. The treatment options are conservative management, interventional radiologic embolization, and surgery. Thoracoscopic ligation of the thoracic duct has emerged as a promising and definitive treatment. The case of a 65-year-old Japanese male patient with a rare congenital right aortic arch (typeⅢB1 of Edwardʼs classification) and a severe chyle leak that occurred after a total pharyngolaryngo-esophagectomy (TPLE) is described. The chyle leak was successfully managed by thoracoscopic ligation of the thoracic duct via a left-side approach with the patient in the prone position

Characteristics of the Excited Triplet States of Thiolated Guanosine Derivatives and Singlet Oxygen Generation

Thioguanine is sensitive to UVA light and generates singlet molecular oxygen (1O2*) when exposed to UVA. Three thioguanosine derivatives, 2’,3’,5’–tri–O–acetyl–6–thioguanosine (ta6TGuo), 2’,3’,5’–tri–O–acetyl–8–thioguanosine (ta8TGuo), and 2’,3’,5’–tri–O–acetyl–6,8–dithioguanosine (taDTGuo) were explored photophysically and photochemically. The nanosecond transient absorption and time–resolved near–infrared emission measurements were carried out to investigate the characteristics of their excited triplet states in acetonitrile solution. The quantum yield of intersystem crossing (∅ISC), the intrinsic decay rate constant (k0), the quenching rate constant by 3O2 (kq) and the self–quenching rate constant (kSQ) of their triplet states were all determined. From precise analysis of the quantum yield of 1O2* generation (∅Δ) against the concentration of dissolved molecular oxygen, the fraction of the triplet states quenched by dissolved oxygen which gives rise to 1O2* formation (SΔ) was successfully obtained with high accuracy. The ∅Δ values at low oxygen concentrations reveal these thioguanosines, particularly taDTGuo, can still effectively generate 1O2* under low molecular oxygen concentration like carcinomatous microenvironments. These findings indicate that taDTGuo would perform well as a potential agent for photo–induced cancer therapies

Skeletal muscle loss in the postoperative acute phase after esophageal cancer surgery as a new prognostic factor

Background The postoperative survival rate of patients with esophageal squamous cell carcinoma (ESCC) remains poor compared with other gastrointestinal cancers. We hypothesized that skeletal muscle loss in the postoperative acute phase might be a new predictor for long-term prognosis after highly invasive surgery such as ESCC surgery. Methods The following items were retrospectively investigated. First, whether skeletal muscle loss occurred in the postoperative acute phase of ESCC was verified. Second, the preoperative and intraoperative factors involved in skeletal muscle loss in the postoperative acute phase of ESCC were investigated. Then, whether skeletal muscle loss in the postoperative acute phase affected long-term prognosis was examined. The medical records of consecutive patients who underwent radical esophagectomy for ESCC between January 2010 and February 2015 were retrospectively reviewed; 72 cases were eligible for this study. The total psoas major muscle mass index (TPI) at the level of the third lumbar vertebra (L3) was measured using computed tomography (CT) before surgery and 3 days after surgery. The long-term prognosis was estimated by the Kaplan-Meier method and the multivariate logistic regression model. Results There was already a significant reduction of TPI in the acute phase up to POD 3 after ESCC surgery in comparison with the preoperative baseline TPI (P Conclusion Skeletal muscle loss occurred even in the postoperative acute phase. Furthermore, it is very significant that skeletal muscle loss in the postoperative acute phase of ESCC surgery is involved in the long-term prognosis

Swarming and mating behavior in Ephemera orientalis Mclachlan, 1875 (Ephemeroptera: Ephemeridae) with morphological analyses

Swarming and mating behaviors of a mayfly species, Ephemera orientalis Mclachlan, 1875 were observed in 2015, 2016, and 2018 at a river bank of the Asahi River, Japan. Males started to make swarms between late April and middle May in 2016 and 2018. The numbers of mated pairs in a swarm correlated with the numbers of flying males in a swarm in 2016 and 2018. Swarms were formed during a limited period at dusk most probably because that interval is free from natural enemies. Males competed with each other to copulate with females in swarms. We clarified the function of the forelegs of males, which are significantly longer than those of females. Males used their forelegs to hold up a female from below. Besides forelegs, males have longer tails than females. We will discuss why sexual differences are found in these traits. Our results represent the first observation of swarm mating behavior in E. orientalis

Flap Reconstruction for Esophageal Perforation Following Anterior Cervical Plate Fixation

Anterior cervical plate fixation is a common surgical treatment for cervical spine trauma, disc herniation, or cervical spondylosis. Esophageal perforation following anterior cervical plate fixation is a rare but serious complication. Management of esophageal perforation is controversial; however, we suggest treating most cases surgically because this condition is slow to heal and often fatal. We managed 2 cases of esophageal perforation following anterior cervical plate fixation by flap reconstruction with the pectoralis major muscle in one case and a jejunal free flap in the other. Here, we report our experience and review the surgical indications

Formation of oxidative photoproduct of tri-acetyl-modified 6-thioguanosine by UVA irradiation

Thio-substituted nucleobases such as 6-thioguanine are known to be photosensitive to UVA light and capable of generating singlet molecular oxygen (1O2*). 2’,3 ’,5 ’- Tri-O-acetyl-6-thioguanosine (ta6TGuo) was prepared and its photochemistry was investigated. ta6TGuo in the aerated acetonitrile solution under UVA irradiation generates 1O2* that can also oxidize ta6TGuo itself and finally convert into tri-acetylated guanosine sulfonate (taGuoSO3). The decay rate constant of ta6TGuo was found to be in good agreement with the formation rate constant of taGuoSO3, revealing that the first step in the reaction of ta6TGuo with 1O2* would be the rate-determining step in forming taGuoSO3 as the final product. Thiolated nucleosides such as 6-thioguanosine could be used as a photosensitive agent for light-induced therapies. The key feature in the UVA irradiation of the thionucleosideis to produce 1O2*, but the resultant oxidative products would also contribute to the effect on therapies

A Heterothermic Kinetic Model of Hydrogen Absorption in Metals with Subsurface Transport

A versatile numerical model for hydrogen absorption into metals was developed. Our model addresses the kinetics of surface adsorption, subsurface transport (which plays an important role for metals with active surfaces), and bulk diffusion processes. This model can allow researchers to perform simulations for various conditions, such as different material species, dimensions, structures, and operating conditions. Furthermore, our calculation scheme reflects the relationship between the temperature changes in metals caused by the heat of adsorption and absorption and the temperature-dependent kinetic parameters for simulation precision purposes. We demonstrated the numerical fitting of the experimental data for various Pd temperatures and sizes, with a single set of kinetic parameters, to determine the unknown kinetic constants. Using the developed model and determined kinetic constants, the transitions of the rate-determining steps on the conditions of metal-hydrogen systems are systematically analyzed. Conventionally, the temperature change of metals during hydrogen adsorption and absorption has not been a favorable phenomenon because it can cause errors when numerically estimating the hydrogen absorption rates. However, by our calculation scheme, the experimental data obtained under temperature changing conditions can be positively used for parameter fitting to efficiently and accurately determine the kinetic constants of the absorption process, even from a small number of experimental runs. In addition, we defined an effectiveness factor as the ratio between the actual absorption rate and the virtually calculated non-bulk-diffusion-controlled rate, to evaluate the quantitative influence of each individual transport process on the overall absorption process. Our model and calculation scheme may be a useful tool for designing high-performance hydrogen storage systems