[Molecular features of metanephric adenoma and their values in differential diagnosis]

Objective: To study the molecular features of metanephric adenoma (MA) and discuss their values in differential diagnosis. Methods: BRAF V600E immunohistochemistry (IHC) using the mutation-specific VE1 monoclonal antibody and Sanger sequencing of BRAF mutations were performed on 21 MAs, 16 epithelial-predominant Wilms tumors (e-WT) and 20 the solid variant of papillary renal cell carcinomas (s-PRCC) respectively. p16 protein was detected by IHC also. Fluorescence in situ hybridization (FISH) analyses using centromeric probes for chromosome 7 and 17 were performed on the three renal tumors in parallel. Results: Fourteen (14/21, 66.7%) of 21 MA cases demonstrated diffuse, moderate to strong cytoplasmic BRAF V600E IHC staining and the BRAF V600E protein expression was detected in 2 (2/16) of 16 e-WT cases for the first time, whereas all s-PRCCs were negative (P<0.05). All cases (including 14 MAs and 2 e-WTs) with diffuse, moderate to strong cytoplasmic BRAF V600E IHC staining were confirmed to harbor BRAF V600E missense mutations using Sanger sequencing, and no BRAF mutations were detected in cases with negative BRAF V600E protein expression. One case (1/21, 4.8%) showed trisomy of chromosome 7 alone, and another one (1/21, 4.8%) showed trisomy of chromosome 17 alone in 21 MAs. Two cases (2/16) of 16 e-WTs showed trisomy of chromosome 17 alone. In 20 s-PRCCs, trisomy of chromosomes 7 alone was reported in 2 cases (2/20), trisomy of chromosome 17 alone in 3 cases (3/20) and trisomy of chromosome 7 and 17 in 14 cases (14/20). The total positive rates of trisomy of chromosome 7 and/or 17 in MAs, e-WTs and s-PRCCs were 9.6% (2/21), 2/16 and 95.0% (19/20). p16 protein was positive in 81.0% (17/21) MAs, whereas the positive rates in e-WTs and s-PRCCs were 2/16 and 5.0% (1/20). Conclusions: Most MAs harbor BRAF V600E mutations, and MAs lack the gains of chromosome 7 and 17 that are characteristic of papillary renal cell carcinoma. These molecular features can be used to distinguish MA from its mimics. BRAF V600E IHC using the mutation-specific VE1 monoclonal antibody provides an effective method in BRAF V600E mutations detection of renal tumors. p16 is overexpressed in MA, and the finding suggests that the low proliferative rate of the tumor might be attributed to BRAF V600E-induced senescence mediated by p16.

[Application of BRAF V600E mutation-specific immunohistochemistry in diagnosis of gastrointestinal stromal tumors]

OBJECTIVE

To evaluate the utility of BRAF V600E allele-specific antibody in the diagnosis of gastrointestinal stromal tumors (GISTs).

METHODS

BRAF V600E mutation-specific immunohistochemistry and BRAF sequencing were performed in 24 consecutive GISTs, including 14 cases of KIT or PDGFRA mutations and 10 cases of KIT/PDGFRA wild GISTs.

RESULTS

GISTs of 11 men and 13 women with a mean age 54 years(range 29-75 years) were included with tumors arising from stomach (16 cases), small bowel (7 cases), and peritoneal cavity (1 case). Strong and diffuse cytoplasmic BRAF staining was noted in 4 of 24 cases (17%), while 1 of 24 cases (4%) showed weak staining, and 19 of 24 cases (79%) had no staining. The four cases with strong BRAF immunostain were confirmed to have BRAF mutations, including 3 cases in the stomach and 1 case in the small intestine. All tumors showed spindle cell morphology. Only one case had progressive disease. No BRAF mutations were detected in cases with weak or negative BRAF immunostain.

CONCLUSION

BRAF V600E mutation-specific immunohistochemistry is a highly sensitive and specific marker for detecting BRAF-mutated GISTs.

[Expression of cadherin17 in metanephric adenoma and its value in differential diagnosis]

OBJECTIVE

To study the expression of cadherin17(CDH17) in metanephric adenoma (MA), and to explore the value of CDH17 in the diagnosis of metanephric adenoma.

METHODS

Immunohistochemical EnVision method was used to detect the expression of CDH17, WT1, CD57, P504S and EMA in 21 cases of MAs, 16 epithelial-predominant Wilms tumors (e-WT), and 20 solid variant of papillary renal cell carcinomas (s-PRCC). The expression of CDH17 was also examined in other common renal epithelial tumors, including 10 cases of clear cell renal cell carcinomas (CCRCC), 10 chromophobe renal cell carcinomas (CHRCC), and 10 oncocytomas.

RESULTS

Twenty (95.2%) of 21 cases of MAs demonstrated membranous CDH17 immunoreactivity in all components (acinar, tubular, and papillary), whereas only 1 (1/16) e-WT was positive for CDH17 and all s-PRCCs were negative (P<0.05). WT1 was negative in s-PRCC and was positive in all cases of e-WT (16/16) and MA (100%, 21/21). All MAs (100%) were strongly positive for CD57; however, this marker was also positive in 13 (13/16) e-WTs and 9 (45.0%, 9/20) s-PRCCs. P504S was strongly positive in all s-PRCCs (100%), but reactivity was seen in 3 (14.3%, 3/21) MAs and all e-WTs were negative. The positive rates of EMA in MAs, e-WTs and s-PRCCs were 19.0%(4/21), 14/16 and 17/20, respectively. The sensitivity and specificity of CDH17 in the diagnosis of MA were 95% and 97%. CDH17 was negative in all cases of CCRCC, CHRCC and oncocytoma.

CONCLUSIONS

CDH17 is a highly sensitive and specific marker for MA and should be considered in the immunohistochemistry panel for distinguishing MA from its mimics and other common renal epithelial tumors.

Supercritical water oxidation of acrylic acid production wastewater

Supercritical water oxidation (SCWO) of wastewater from an acrylic acid manufacturing plant has been studied on a continuous flow experimental system, whose reactor was made of Hastelloy C-276. Experimental conditions included a reaction temperature (T) ranging from 673 to 773K, a residence time (t) ranging from 72.7 to 339s, a constant pressure (P) of 25 MPa and a fixed oxidation coefficient (alpha) of 2.0. Experimental results indicated that reaction temperature and residence time had significant influences on the oxidation reaction, and increasing the two operation parameters could improve both degradation of chemical oxygen demand (COD) and ammonia nitrogen (NH3-N). The COD removal efficiency could reach up to 98.73% at 25 MPa, 773 K and 180.1 s, whereas the destruction efficiency of NH3-N was only 43.71%. We further carried out a kinetic analysis considering the induction period through free radical chain mechanism. It confirms that the power-law rate equation for COD removal was 345 exp(-52200/RT)[COD]1.98[O2]0.17 and for NH3-N removal was 500 exp(-64492.19/RT)[NH3-N]1.87 [O2]0.03. Moreover, the induction time formulations for COD and NH3-N were suspected to be exp(38250/RT)/173 and exp(55690/RT)/15231, respectively. Correspondingly, induction time changed from 2.22 to 5.38 s for COD and 0.38 to 1.38 s for NH3-N. Owing to the catalysis of reactor inner wall surface, more than 97% COD removal was achieved in all samples.

Giant enhancement of surface second-harmonic generation using photorefractive surface waves with diffusion and drift nonlinearities

Giant enhancement of second-harmonic generation (SHG) with 83.4%/W coversion efficiency is obtained, taking advantage of photorefractive surface waves with diffusion and drift nonlinearity. In this method, the self-bending induced by diffusion nonlinearity can be utilized at the surface and can solve the phase-mismatch problem in bulk due to beam self-bending. With drift nonlinearity, an applied external electric filed and background illumination can further constringe surface waves to the surface and consequently enhance SHG, which provides the possibility and flexibility of control.

(2+1)D surface solitons in virtue of the cooperation of nonlocal and local nonlinearities

We introduce a type of (2+1)D surface soliton in virtue of the cooperation of nonlocal and local nonlinearities. Furthermore, taking advantage of diffusion and drift nonlinearity this type of surface soliton is demonstrated theoretically and experimentally in a storintium barium nitrate crystal. The dynamics behavior of the excitation and propagation of this type of surface soliton are studied using the beam-propagation method and the nonlinear equation of light rays.

Influences of MxA gene -88 G/T and IFN-gamma +874 A/T on the natural history of hepatitis B virus infection in an endemic area

The influence of human genetics on the natural history of hepatitis B virus (HBV) infection may be diminished in endemic areas because infection at a young age predisposes to chronic HBV infection. The present study aimed to address this issue through the determination of the influences of single nucleotide polymorphisms (SNPs) of myxovirus resistence-1 (MxA) -88 G/T and interferon (IFN)-gamma +874 A/T on the natural history of HBV infection in endemic regions. One hundred adult patients with self-limiting HBV infection (positive for both anti-HBs and anti-HBc) and 340 adult patients with persistent HBV infection were recruited from southern China, an endemic area with an HBsAg carrier rate of 17.8%. SNPs of MxA -88 G/T and interferon (IFN)-gamma +874 A/T were typed using a protocol based on competitively differentiated polymerase chain reaction. A highly significant difference in the distribution of MxA -88 G/T was observed between those with persistent and self-limiting HBV infections. The latter displayed a lower frequency of the GG genotype (41.0% vs. 52.9%, P = 0.036) and a higher frequency of the TT genotype (16.0% vs. 2.4%, P = 0.000), compared to patients with persistent infection. These differences were not gender- or age-specific. However, a significant distribution difference of IFN-gamma +874 A/T was not observed. Between two groups of patients, respectively, the distribution frequencies of the AA genotype (65.0% vs. 72.8%, P = 0.139) and the TT genotype (2.0% vs. 1.2%, P = 0.894) were found. These results suggest that MxA gene -88 G/T and IFN-gamma +874 A/T behave differently in endemic HBV infections. Further study is necessary to clarify the influences of human genetics on endemic HBV infections.

[Detection of coxsackie virus B3 gene in myocardium and spleen samples in myocarditis with sudden death]

OBJECTIVE

To detect the Coxsackie virus B3(CVB3) gene in myocardium and spleen tissues in viral myocarditis(VMC) with sudden death and to explore the diagnostic method for VMC by means of seeking pathogene.

METHODS

By in situ RT-PCR, the detection of CVB3 gene in myocardium and spleen sections were performed in sudden death group caused by VMC and non-cardiac death group.

RESULTS

In VMC group, CVB3 gene-positive signals were seen in myocardium sections(3 out of total 8 cases, No. 1, 4, 7 cases) and spleen sections(4 out of total 8 cases, No. 2, 4, 6, 7 cases). In non-cardiac death group, no positive signals were detected in both myocardium and spleen tissues.

CONCLUSION

Positive detection of CVB3 gene in both myocardium and spleen maybe an important character of VMC and can improve the detecting pathogene in diagnosing VMC.

Parameterization of inoculum effect via mathematical modeling: aminoglycosides against Staphylococcus aureus and Escherichia coli

Inoculum effect describes the inoculum size dependent changes in minimum inhibitory concentrations (MIC) exhibited by antibiotic-bacterium combinations demonstrating such effect. Traditionally, inoculum effect has been loosely defined based on the extent of increase in the MIC with respect to the increase in inoculum size. In most studies, assessment of MIC data has relied on the arbitrary selection of a point of reference for both baseline MIC and inoculum size. More importantly, this conventional method of assessment does not permit information conveyed in a complete MIC versus inoculum size profile to be fully explored. To undertake these issues, a mathematical model was developed for the description of the entire inoculum effect profile. With the employment of three key parameter estimates, i.e., the baseline MIC, the threshold inoculum size at which the increase in MIC commences, and the rate of increase in MIC with respect to inoculum size, both the shape and location of the profile could be adequately defined. To verify the application of this model, a series of four aminoglycosides were tested against standard strains of E. coli and S. aureus. Results showed a good degree of organism specificity and antibiotic-class dependency of the inoculum effect profiles. Analysis of the parameter estimates obtained provided further support for these observations. In conclusion, the mathematical model developed in the present study adequately described the inoculum effect exhibited by the various aminoglycoside-bacterium combinations tested. The parameter estimates generated by the modeling approach allowed comparison and quantitative analysis of the inoculum effect profiles with minimal difficulties.

Mitral insufficiency as a complication of acute myocardial infarction and left ventricular remodeling

The presence of mitral insufficiency after acute myocardial infarction (AMI) often leads to hemodynamic impairment and heart failure. This study was designed to examine the relationship between mitral regurgitation (MR), an indicator of mitral insufficiency, and the course of recovery from AMI. We evaluated the course of MR after AMI in 223 patients by color Doppler echocardiography. MR was detected in 21% (47/223) of patients at the onset of AMI, and developed in 18% (40/223) of patients during follow-up. Patients were grouped according to the course of MR as well as the success of acute recanalization therapy. No correlation was observed between the presence or course of MR and the site of infarction. The incidence of successful recanalization was higher in patients with MR that improved during follow-up than in patients with MR that was unchanged or that worsened during follow-up. Although no significant differences in hemodynamic variables were noted among the groups at admission, the group with unsuccessful recanalization and unimproved MR (BS-) showed a significantly greater left ventricular end-diastolic diameter (LVDd), left ventricular end-systolic diameter, and left ventricular end-diastolic volume (LVEDV) as well as a lower left ventricular ejection fraction than patients with successful recanalization and no MR (CS+) during the convalescent period. The extent of change in LVDd and LVEDV between admission and convalescence was significantly greater in the BS(-) group than in the CS(+) group. The results suggest that successful recanalization after AMI reduces the incidence of MR. Acute recanalization therapy after AMI may prevent left ventricular remodeling, resulting in a secondary improvement of MR.

Unilateral cleft lip repair without making incisions on the lip surface. A modified Millard operation

In clinical and anatomical studies carried out during 1986-1990, two new findings were identified: a small spade-shaped myocutaneous tag which can often be found at the medial side of the cleft near the columella base and the levator septi nasi muscle which draws the cleft side of the philtrum upwards. With the full use of the two findings, a method of unilateral cleft lip repair without making incisions on the lip surface was developed. Since 1986, 52 cases of unilateral cleft lip have been repaired with this method. The early and late results were gratifying.