Inadequate gastric preparation and its associated factors for magnetically controlled capsule endoscopy.

Goals: To explore factors associated with inadequate gastric preparation for MCE. Background: Factors associated with inadequate gastric preparation for magnetically controlled capsule endoscopy (MCE) remains unclear. Study: Data of patients who underwent MCE from June 2021 to July 2022 were prospectively collected. The gastric cleanliness score (GCS) of the six stomach regions (gastric cardia, fundus, body, angulus, antrum, and pylorus) was recorded. Patients with GCS score ≥18 were defined as the adequate preparation. Factors related to inadequate gastric preparation were analyzed using a logistic regression model with estimated odds ratios (OR). Results: The mean GCS score of 211 patients was 17.01 ± 2.82. In the multivariable analysis, proton pump inhibitor (PPI) use (OR 3.57; 95% CI 1.69-7.95; p < 0.01) and premedication time after administering simethicone <30 min (OR 2.86; 95% CI 1.10-7.39; p = 0.03) were independent risk factors for inadequate gastric preparation. Comparing the gastric cleanliness of different locations, the median GCS of the lower stomach [10.00, IQR (9.50, 11.00)] was significantly higher than that of the upper stomach [7.00, IQR (6.00, 8.00)] (p <0.001). Conclusion: PPI use and inadequate premedication time (<30 min) may reduce the quality of gastric preparation for MCE. The type, dose, duration of medication, and discontinuation time of PPIs was well worth further exploration. Appropriate control of the type and time of premedication may be the key to improving overall gastric cleanliness.

[Ultrasound characteristics of testicular Leydig cell tumors , , , 1.]

OBJECTIVE: To explore the color Doppler ultrasonic characteristics of testicular Leydig cell tumors (LCT) and improve the clinical diagnosis of the disease. METHODS: We retrospectively analyzed 4 cases of testicular LCT diagnosed and treated in our hospital and summarized the experience in the ultrasonic diagnosis of LCT with a review of the relevant literature. RESULTS: All the 4 testicular LCTs were solitary and quasi-round, 1 in the left and 3 in the right. The smallest mass was 1.8 × 1.5 cm and the largest 3.1 × 2.5 cm, and 2 were complicated by hydrocele of tunica vaginalis. The margins of tumors were distinct in 2 cases and indistinct in 1, and changed from distinct to indistinct in another during the follow-up. Hypoechoes were revealed in all the 4 cases in ultrasonography, 2 with abundant internal blood flow, 1 with abundant peripheral blood flow, and the other with abundant internal blood flow changed from circular blood flow surrounding the mass. CONCLUSIONS: A typical sporadic LCT was ultrasonically manifested as an isolated hypoechoic infracentimetric mass with a clear demarcation from the adjacent pulp. It exhibited intrinsic hypervascularization associated with a typical peripheral rim pattern. Larger lesions more often presented a lobulated shape and intense hypervascularization. Although these ultrasonic characteristics do not reveal the nature of LCT with certainty, they can help the surgeon with the decision on testis-sparing surgery or perhaps even on the active monitoring for the smallest lesions in a population with impaired fertility.

[Clinicopathologic analysis of spermatocytic seminoma].

OBJECTIVE: To study the clinicopathologic features and biological behavior of spermatocytic seminoma. METHODS: A retrospective analysis of patients diagnosed as seminoma, spermatocytic seminoma between January 2003 and May 2011, was performed. Clinical data, HE stained section and immunohistochemical staining (SP method) were reviewed with follow-up. RESULTS: Sixty-six cases of seminoma and 5 cases of spermatocytic seminoma were identified. The average age at the diagnosis of 5 cases of spermatocytic seminoma was 53 years, and no patient had a history of crytorchidism or germ cell tumor. All five patients had stage pT1 tumor. Immunohistochemical studies showed that spermatocytic seminoma was negative for CK, vimentin, OCT3/4, PLAP, and LCA, and PAS staining was also negative. All five patients were well after operation. In contrast, the average age at diagnosis of the 66 cases of seminoma was 37 years, in which 12% had a history of crytorchidism and 11% were in stage pT2 or the above. Immunohistochemical studies showed that seminoma was positive for OCT3/4, PLAP, and CD117. During the follow-up, 2 patients developed metastasis and 3 patients died of the disease. CONCLUSIONS: Spermatocytic seminoma is rare and appears to follow a benign clinical course Due to its favourable prognosis, further treatment is not necessary after orchidectomy. Accurate pathologic diagnosis is critical for patient management and for avoiding over-treatment.

Biexponential theory of Drude dissipation via hierarchical quantum master equation.

A nonperturbative quantum dissipation theory is developed based on an optimal construction of biexponential Drude bath correlation function for its influence on the system dynamics. It is an advanced hierarchical quantum master equation approach, aiming at a numerically efficient non-Markovian quantum dissipation propagator, with the support of a convenient criterion to estimate in advance its accuracy for general systems. Compared to its low level, single-exponential counterpart [R. X. Xu et al., J. Chem. Phys. 131, 214111 (2009)], the present theory remarkably improves the applicability range over all-parameter space, as tested critically with electron transfer and frequency-dispersed transient absorption of exciton dimer model systems.

Hierarchical quantum master equation with semiclassical Drude dissipation.

We propose a nonperturbative quantum dissipation theory, in term of hierarchical quantum master equation, which may be used with a great degree of confidence to various dynamics systems in condensed phases. The theoretical development is rooted in an improved semiclassical treatment of Drude bath, beyond the conventional high temperature approximations. It leads to the new theory a simple but important improvement over the conventional stochastic Liouville equation theory, without extra numerical cost. Its broad range of validity and applicability is extensively demonstrated with two-level electron transfer model systems, where the new theory can be considered as the modified Zusman equation. Criterion is also proposed to estimate the performance of the hierarchical quantum master equation.

Presacral extrarenal Wilms tumor in a child.

OBJECTIVES: Wilms tumor (WT) is one of the most common solid tumors in children. It also is the most frequent tumor found in the kidneys. In 5% of cases, it affects both kidneys simultaneously. Extrarenal WTs are extremely rare. The diagnosis of extrarenal WT is almost always made after surgical intervention. The tumor can be located in the retroperitoneum, uterus, cervix, testes, skin, and even the thorax. METHODS: We report on a 3-year-old girl with an extrarenal WT located in the presacral region. RESULTS: The exact mechanism whereby a WT occurs in extrarenal tissues is unknown. The presence of ectopic metanephric blastema cells or the WT gene causing transformation of extrarenal primitive mesonephric or pronephric remnants into WT have both been considered in the embryogenesis. Although imaging examinations are helpful in the definition of retroperitoneal tumors, no characteristic findings are available to diagnose an extrarenal WT before surgery. CONCLUSIONS: As a rule, the diagnosis of extrarenal WT is made after surgery. Surgical excision is the treatment of choice and the same general therapeutic rules should be followed as when the kidney has been affected. The use of Stage III guidelines for chemotherapy and radiotherapy are appropriate for these patients.

Exact dynamics of driven Brownian oscillators.

Exact quantum master equation for a driven Brownian oscillator system is constructed via a Wigner phase-space Gaussian wave packet approach. The interplay between external field and dissipation leads to this system an effective field correction that enhances the polarization. This cooperative property is resulted from an effective bath response to the external field applied on the system. It is important in the low-frequency driving and intermediate bath memory region. We demonstrate this non-Markovian effect on the linear response and nonlinear dynamics and analyze the results together with analytical asymptotic expressions.

[Relationship between TIMP-3 expression and promoter methylation of TIMP-3 gene in hepatocellular carcinoma].

OBJECTIVE: To investigate further the possible mechanism of carcinogenesis and portal invasion of hepatocellular carcinoma (HCC). METHODS: Samples of the primary tumors, cancer cells emboli in the portal veins and normal liver tissues adjacent to the tumor were collected from 20 cases of primary HCC. Expression of TIMP-3 (tissue inhibitor of metalloproteinases-3) protein was detected using Western blot. Expression of TIMP-3 mRNA was detected by RT-PCR. Methylation of TIMP-3 gene promoter was detected using methylation-specific PCR (MSP). RESULTS: Expression of TIMP-3 protein and mRNA were obtained in all of the normal liver tissues adjacent to tumor. However, loss of TIMP-3 protein expression was found in 5 and 36 cases respectively in the primary tumors and tumor cell emboli in portal veins. Expression of TIMP-3 protein and mRNA in primary tumors and tumor emboli were significantly lower than that in the normal liver tissues. Promoter methylation of TIMP-3 gene could be detected in primary tumors (7 cases) and cancerous emboli (9 cases) in HCC, while no methylation found in normal liver tissues. In all the HCC cases with promoter gene methylation including primary tumors and cancerous emboli in portal veins, 13 cases showed complete loss and 6 cases showed low expression of TIMP-3 protein and mRNA. Promoter methylation of TIMP-3 was noticed not related with the histological grading of HCC. CONCLUSIONS: There is a close relationship between loss or low expressions of TIMP-3 and carcinogenesis and portal invasion of HCC. The loss and low expression of TIMP-3 gene and protein were caused by methylation of the gene promoter.