Objective To study histological and cytological characteristics of malignant mesothelioma of the peritoneum by needle biopsy. Methods Needle biopsy specimens of 19 cases of malignant mesothelioma of the peritoneum were studied with pathological, cytological, histochemical and immunohistochemical staining examination. Results Of 19 cases, 12 were males and 7 were females, with a mean age of 58.1 years. Histopathlogical examination of needle biopsy specimens revealed that 10 of them were tubulopapillary. 3 undifferentiated. 1 signet ringoid cell, 1 small cell, 2 of low-grade malignant cystic cell and 2 of myofibroblastic cell types. 16 cases were positive by cytology smear but 3 negative. Immunohistochemical staining showed that the neoplastic cells of all cases were positive for keratin, vimentin, EMA, antimesothelial cell antigen and CI but negative for HCI. Conclusion The diagnosis of malignant mesothelioma of the peritoneum can be established by its clinical manifestation, combined with pathological, cytological, histochemical staining and immunohisitochemical staining of specimens obtained by ultrasound guided needle biopsy.

Objective To study the clinicopathologic features and prognosis of low-grade malignant cystic mesothelioma of the peritoneum (LGMCMP). Methods 25 cases of LGMCMP were analyzed retrospectively on their clinicopathologic features and immunohistochemical and electron microscopic findings, therapeutic approach and prognosis were also studied. Results Of 25 cases, 18 were females and 7 were males with a mean age of 39.6 years (range 16-84 years). According to their imaging characteristics, symptoms and physical signs, three morphological patterns of these tumors were found, i.e. localized cystic mass, multiple cystic nodules and diffuse cystic nodules. Immunohistochemical staining showed that the neoplastic cells were positive for CK, Vimentin, EMA, and anti-mesothelial cell antigen. Histochemically, the tumors were positive for CI but negative for HCI. Electron microscopic study of 11 cases revealed that the neoplastic cells had profuse slender microvilli on cell surface, large amount of microfilaments (tono-filaments) and abundant desmosomes. Conclusion LGMCMP is an uncommon neoplasm of low-grade malignancy, generally occurring in young women with distinct clinicopathologic features.

cases of focal nodular heperplasia of the liver were studied with HE staining and immunohistochemistry. The patient population was composed of 12 males and 5 females, aged 13 to 71 years. The main symptom was abdomimal pain or discomfort. 9 patients were misdiagnosed as hepatic cell carcinoma (HCC) before operation. Histologically, 14 cases were of classical form, and 2 cases were of telangiectatic form, and 1 case mixed form. The classical form of FNH was defined by the presence of 4 characteristic histologic features: nodular central stellate scar, abnormal nodular architecture, malformed vessels, and cholangiolar proliferation. The causes of focal nodular hyperplasia of the liver were briefly discussed.

Objective To analyse the clinical and pathological features of cystadenocarcinoma in the intrahepatic biliary tract. Methods The clinical features of 14 patients with cystadenocarcinoma in intrahepatic biliary tract were analysed in respect to the results of ultrasonic and CT scannings, as well as pathological examination. Results Among the 14 patients, 11 were females and 3 were males. The age of the patients ranged from 32 to 79 years, and mean age was 59.5. The obvious symptoms were right-upper abdominal pain and abdominal distention, and major physical signs were hepatomegaly with cystic feeling. The ultra sonographic and CT scanning revealed cystic space occupying lesions in the liver. According to the invasion or infiltration of carcinoma to the liver tissue, the pathology of cystadenocarcinoma in intrahepatic biliary tract could be categorized into two types: the invading and non-invading. There were 8 patients belonging to the first type and they died 9～37 months after the diagnosis or operation, while 6 patients with no invasion were alive after operation. Conclusion The clinical picture and pathology of cystadenocarcinoma in intrahepatic biliary tract were described. The pathological classification was important in prognosticating the outcome of the patient.

Objective To explore the diagnostic value of β‐human chorionic gonadotropin (β‐HCG) and its free β‐subunit (fβ‐HCG) of adverse pregnancy .Methods Chemiluminescence technique was used for the detection of serum levels ofβ‐HCG ,fβ‐HCG and progesterone in women with early adverse pregnancy (threatened abortion group ,missed abortion group and ectopic pregnancy group) and normal pregnant women (control group) ,respectively .The 48 h doubling rate ofβ‐HCG of each group was calculated . And the results were analyzed .Results Comparing with threatened abortion group ,there were significant differences in the levels of β‐HCG ,fβ‐HCG ,progesterone and doubling rate both of missed abortion group and ectopic pregnancy group (P<0 .05) .How‐ever ,there was no difference in these indicators between missed abortion group and ectopic pregnancy group ( P> 0 .05 ) . Conclusion T he changes of β‐HCG and fβ‐HCG can reflect adverse pregnancy .

Objective To investigate the effect of luxS inactivation on the oxidative stress of Streptococcus mutans and perform preliminary analysis of potential mechanism.Methods Strains were grown to mid-logarithmic phase and divided into three groups,one was used as control and inoculated into normal TPY medium,and the other two groups were experimental groups,and there were separately inoculated into TPY containing 58.8 mmol/L hydrogen peroxideor TPY containing 58.8 mmol/L hydrogen peroxide and 0.1 mmol/L 2,2'-dipyridyl.The survival rate of strain was calculated at 0.5,1,and 2 h.All the data were statistically analyzed.Results Compared with the control group,the survival rate of luxS mutation was always higher than standard strain at all pre-determined time inexperimental groups (P＜0.05),and compared with experimental group without iron chelator,the survival rate of strains was not raised with the added of iron chelator (P＞0.05).Conclusion luxS gene is involved in oxidative stress tolerance of Streptococcus mutans,and the oxidative stress tolerance is not achieved by avoiding the toxic effects of the Fenton reaction

Objective To construct markless gene deletion mutant at the clpP loci on the chromosome of Streptococcus mutans(S.mutans).Methods ASp resistance gene was amplified by PCR,to construct the Sp resistance cassette where the Sp resistance gene was flanked with two loxP site.After the clpP gene was cloned into the pGEM-T-Easy TA cloning vector,it was digested and linked with the Sp resistance cassette,yielding homologous recombination vector pIB △ clpP-Sp.The vector was linearized and used for the transformation of S.mutans UA159,with transformants selected on TPY plates containing Sp.The selected strain was transformed with the thermosensitive plasmid pCrePA to excise the Sp resistance gene.The pCre-PA was then easily eliminated at nonpermissive temperature,resulting in a markless mutant strain carrying a deletion at the clpP loci,which was verified by PCR and DNA sequencing.Results The result of the PCR analysis and DNA sequencing indicated that a part of the clpP gene was deleted.There was a loxP at this loci without the Sp resistance gene.Conclusion The markless clpP-deletion mutant of S.mutans was constructed successfully,which laid a foundation for further study of its biological function and its influence on the cariogenicity of S.mutans.

Objective To knock out the entire LuxS gene of Streptococcus mutans UA159 strain via homologous recombination and construct a LuxS-deleted mutant strain of S.mutans.Methods The erythromycin resistance gene(Eymr)was inserted between the two DNA fragments located in the upper and downstream of LuxS gene that had been amplified by PCR.Then the two DNA fragments along with the inserted Eymr were engineered into pUCl9 plasmid to construct the recombination plasmid pUCluxKO.Electrotransformation of S. mutans cells with pUCluxKO-mutant resulted in the isolation of erythromycin resistant S.mutans,transformants,which was then subjected to polymerase chain reaction,Vibrio harveyi BBl70 luminescence bioassay and sequencing analysis.Results Restriction endonuclease analysis showed that pUCluxKOmutant vector had been successfully recombined.The deletion of LuxS of S. mutans mutants was confirmed bv PCR with primers specific for the genes of LuxS and the erythromycin resistance.S.mutans mutant could not induce bioluminescence.indicating the mutant had been successfully recombined.The constructed Chinese S.mutans showed good stability after 20 generations of cultivation.Conclusion The S.mutans gene allelic exchange plasmid is constructed correctively and a LuxS-negative mutant of S.mutans has been constructed.which can be helpful for further study of the role of LuxS in the pathogenesis of S.mutans.

Objective To characterize the image morphology and time-intensity curve of renal cell cancer and angiomyolipoma on contrast-enhanced harmonic sonography. Methods A total of 57 patients with 58 renal masses were enrolled in this study prospectively. The renal masses included 47 renal cell carcinomas (RCC) and 11 angiomyolipomas (AML). All patients were evaluated by tradi-tional gray-scale sonography, color Doppler sonography and contrast-enhanced harmonic sonography. Imaging findings and time-intensity curves of all renal masses were analyzed. The contrast-enhance-ment features between RCC and AML were analyzed. Results 57.4% of RCCs were hyperechoic masses and peripheral surrounding vessels and / or penetrating vessels were noted in 83.0% of RCCs on color Doppler sonography. 54.5 % of AMLs were hyperechoic masses while peripheral surrounding vessels and / or penetrating vessels were only noted in 27.3% of AMLs on color Doppler sonography. On contrast-enhanced harmonic sonography, hyper- or iso-enhancement were noted in 83.0% of RCCs, while hypo-enhancement were noted in 81.8% of AMLs (P<0.01). Statistically significant differences were noted between RCC and AML in the values of peak time (P=0.03), wash time (p= 0.02), peak intensity-basic intensity (P=0. 01), AT/R (△A tumor/△A renal) (P=0.00), k (P= 0.02), and Aok (P=0.02). Conclusions Contrast-enhanced sonography is useful in the differentia-tion of renal masses. Most RCCs are hyper- or iso-enhanced while most AMLs are hypo-enhanced. Time-intensity curves are helpful in differentiating RCC and AML.

Objective: To study the difference between the acid resistance of Streptococcus mulans Ingbritt C international standard strain and the acid resistance of LuxS mutant strain. Methods: Solutions of Streptococcus mulans standard strain and LuxS mutant strain with same density were prepared and cultured at pH 3. 5 to 7. 0 BH1 liquid for same period. Terminal growth situation was compared. After being acidized in pH 5.5 BHI liquid, the two strains were cultured at pH 3.0 BHI liquid. The acid tolerance responses of the two strains were compared. Results; (DAt pH 6.0 to 7. 0, the difference of growth between Streptococcus mulans standard strain and LuxS mutant strain was not significant at the same pH value, and the differences of bacterial growth situation under three different pH values were not significant. (1)At pH 4.5 to 5.5, the difference of growth between the two strains was significant. (2)At pH 3.0,the survival rate of LuxS mutant strain(0.006 5% )was significantly lower than the standard strain (0.078% ). (3)At pH 5.5, the survival rate of LuxS mutant strain(0.747% ) was lower than the standard strain(8.65% )by about 10 times after the pre-acidification. Conclusion; (4)At sub-lethal pH value, there is significant difference of aciduricity between Streptococcus mu-tans standard strain and LuxS mutant strain. The acid resistance of standard strain is stronger than that of LuxS mutant strain. The two strains both display the capability of acid tolerance responses. LuxS mutant strain is more sensitive to acid inactivation, but the capability of acid tolerance responses still exists.