Complex anatomy surrounding the left atrial posterior wall: analysis with 3D computed tomography

Few studies have explored the topographic anatomy of the esophagus, posterior wall of the left atrium (LA), or fat pads using multidetector computed tomography (MDCT) to prevent the risk of esophageal injury during atrial fibrillation (AF) ablation. MDCT was performed in 110 consecutive patients with paroxysmal or persistent AF before the ablation procedure to understand the anatomic relationship of the esophagus. Two major types of esophagus routes were demonstrated. Leftward (type A) and rightward (type B) routes were found in 90 and 10% of the patients, respectively. A type A route had a larger mean size of the LA than type B. The fat pad was identifiable at the level of the inferior pulmonary vein in 91% of the patients without any predominance of either type. The thickness of the fat pad was thinner in the patients with a dilated LA (>42?mm) than in those with a normal LA size (??42?mm) (p?=?0.01). The results demonstrated that the majority of cases had a leftward route of the esophagus. There was a close association between the LA dilatation and fat pad thinning. With a dilated LA, the esophagus may become easily susceptible to direct thermal injury during AF ablation. Visualization of the anatomic relationship may contribute to the prevention of the potential risk of an esophageal injury.     

An enrichment medium for increasing a very small number of vibrio parahaemolyticus cells to the detection limit of the loop-mediated isothermal amplification (LAMP) assay

We developed an enrichment medium for use with the loop-mediated isothermal amplification (LAMP) assay (enrichment media + LAMP assay) to quickly increase a very small number of Vibrio parahaemolyticus cells to the detection limit of the assay. Thirty-nine different enrichment media were prepared based on evaluating 12 potential ingredients. From our assessment of the 39 media, enrichment medium #36, which contained 2% sodium chloride, 1% proteose peptone no. 2, 0.1% trehalose, 0.5% α-ketoglutaric acid, 0.25% pyruvic acid, and 0.5% yeast extract (pH 8.6), was found to be most effective at enhancing the proliferation of V. parahaemolyticus during incubation for 3 h at 40oC. We compared the detection limits of the LAMP assay, the enrichment medium #36 + LAMP assay, and the cultivation method using bacterial cell and spiked shrimp sample tests. The detection limits of the LAMP assay, the medium #36 + LAMP assay, and the cultivation method were 10(3), 10(0)-10(-1), and 10(-1) CFU ml(-1), respectively. Enrichment medium #36 promoted a 10(3)- to 10(4)-fold increase in the bacterial population, and the detection limit of the enrichment media + LAMP assay was the same as that of the cultivation method.     

Treatment extension may benefit female genotype 1 chronic hepatitis C patients with complete early virological response to peginterferon-alpha-2b and ribavirin combination therapy

Aim: Little is known about the appropriate use of peginterferon‐α‐2b (PEG IFN‐α‐2b) or ribavirin (RBV) in genotype 1 chronic hepatitis C (CH‐C) patients with complete early virological response (cEVR). Female patients, especially the older, are known to experience inferior treatment outcomes. Method: A total of 150 CH‐C patients with cEVR treated for 48 weeks (n = 104) or 52–64 weeks (n = 46) with PEG IFN‐α‐2b and RBV combination therapy were retrospectively analyzed to evaluate the benefits of extended treatment. Results: In the 48‐week group, patients without a sustained virological response (SVR) were more often female (P = 0.004) and had received a significantly lower total RBV dose (P = 0.003) than those with SVR. The SVR rate in these female patients was similar to males with hepatitis C virus (HCV) RNA negativity at treatment week 8 (P = 0.413); however, it was lower than that in males with HCV RNA negativity at treatment week 12 (P = 0.005). In the 52–64‐week group, although the total RBV dose (mg/kg) after treatment week 48 was less in females than in males (P = 0.027), the SVR rate in females was equivalent to that in males (P = 0.604). Conclusion: Genotype 1 CH‐C patients treated with PEG IFN‐α‐2b and RBV combination therapy without SVR were more often female and had received a lower total RBV dose than males. The smaller SVR rate in female patients with cEVR compared to males may be overcome by extending treatment even if the RBV dose is lowered due to anemia.     

A newly designed bioabsorbable substitute for the treatment of diaphragmatic defects

Purpose

Earlier studies have investigated the suitability of various materials and autologous grafts for the repair of diaphragmatic defects. Our group investigated the feasibility of using an artificial diaphragm (AD) to repair wide diaphragmatic defects.

Methods

Twelve pigs were laparotomized and, in each pig, a defect was fashioned by resecting a round 8-cm diameter hole in the left diaphragm. Next, the defect was repaired by implanting an AD. The animals were relaparotomized 8 or 24 weeks after implantation for gross, histological and radiological observation of the implanted sites.

Results

All recipient animals survived until killing for evaluation. Chest X-ray examinations showed no differences between the preoperative diaphragms and the grafted diaphragms at 8 and 24 weeks after implantation. At 8 weeks after implantation, the implanted sites exhibited fibrous adhesions to the liver and lungs without deformities or penetrations. Parts of the surface tissue at the graft sites had a varnished appearance similar to those of the native diaphragm. Histology performed at 8 weeks detected no trace of the ADs in the graft sites; however, numerous inflammatory cells and profuse fibrous connective tissue were observed. At 24 weeks after implantation, no differences were found in the thorax between the areas with the grafts and the unaffected areas. Histology of the graft sites in the thorax confirmed growth of mesothelial cells similar to that observed in the native diaphragm.

Conclusions

Artificial diaphragms can be a novel substitute for diaphragmatic repair.     

Intersphincteric resection for very low rectal cancer: a systematic review

Radical surgical treatment for very low rectal cancer near the anus has generally involved abdominoperineal resection. Various sphincter-saving operations have been developed for such tumors to optimize the patients’ postoperative quality of life. Current protocols focus on intersphincteric resection (ISR), which differs from conventional hand-sewn coloanal anastomosis (CAA) after low anterior resection. However, the efficacy of ISR remains unclear. The surgical, oncologic, and functional outcomes after intersphincteric resection (ISR) were reviewed. This review of the current literature was conducted by searching the PubMed online database. Articles focusing specifically on conventional hand-sewn CAA were excluded from this study. The mean mortality rate is <2 %, and the mean morbidity rate ranges from 7.7 to 38.3 %. The mean local recurrence rate varies widely from 0 to 22.7 %, with a mean follow-up duration of 40–94 months. The mean disease-free and overall 5-year survival rates are 69–86 and 79–97 months, respectively. Functional outcomes are generally acceptable, but accurate evaluation is extremely difficult due to the absence of unified appraisal methods. ISR appears surgically, oncologically and functionally acceptable. However, more experience and better understanding of the oncology, anal physiology, and pelvic anatomy are necessary to achieve successful outcomes without complications, and to improve patient survival.