Filamentation initiated by Cas2 and its association with the acquisition process in cells / 国际口腔科学杂志·英文版

Cas1-and-Cas2-mediated new spacer acquisition is an essential process for bacterial adaptive immunity. The process is critical for the ecology of the oral microflora and oral health. Although molecular mechanisms for spacer acquisition are known, it has never been established if this process is associated with the morphological changes of bacteria. In this study, we demonstrated a novel Cas2-induced filamentation phenotype in E. coli that was regulated by co-expression of the Cas1 protein. A 30 amino acid motif at the carboxyl terminus of Cas2 is necessary for this function. By imaging analysis, we provided evidence to argue that Cas-induced filamentation is a step coupled with new spacer acquisition during which filaments are characterised by polyploidy with asymmetric cell division. This work may open new opportunities to investigate the adaptive immune response and microbial balance for oral health.

Clinical Efficacy Observation of Herpes Zoster Treated by Compound Radix Scutellariae Solution Wet Application / 浙江中医药大学学报

Objective]Observe clinical efficacy of herpes zoster treated by the compound radix scutellariae solution wet application. [Method]50 patients were randomly divided into 25 cases of the compound radix scutellariae group and 25 cases of the nitrofurazone group, respectively given wet application of the compound radix scute-llariae solution and nitrofurazone solution, at the same time given intravenousganciclovir 0.3g/time,1 time/d, oral vitamin B1 20mg/time, 3 times/d, oral cobalt amine 0.5mg/time, 3 times/d, one week as a period. Record all patients' pain, skin lesion scores before the treatment and in the course of the third, fifth, seventh day and record the time of herpes stopping hair, blister drying up, blister beginning to scab and the scabby area not less than 50%.[Result] Pain, skin lesion scores of the compound radix scutellariae group were signifycantly lower than those of nitrofurazone group, the time of herpes stopping hair, blister drying up, blister beginning to scab and the scabby area not less than 50% of the compound radix scutellariae group compared with nitrofurazone group in advance, the difference was statistically significant(P<0.05). [Conclusion]Treatment of the compound radix scutellariae solution to herpes zoster had distinct clinical efficacy, having significant advantages in terms of alleviating pain and promoting skin lesions subsided.

Purification and characterization of a sarcosine oxidase from Bacillus sp. BSD-8 / 生物工程学报

We purified a sarcosine oxidase from Bacillus sp. strain BSD-8 isolated from soil. We purified the enzyme by ammonium sulfate precipitation, DEAE-cellulose, Toyopearl hydrophobic and Sephadex G-75 molecular sieve chromatography and characterized the purified sarcosine oxidase. This sarcosine oxidase was a flavin enzyme containing a noncovalently bound flavin with the subunit molecular mass of 51 kDa. The optimal temperature for this enzyme was 60 degrees C and it showed its highest activity at pH 8.5. It was stable in the pH range of 8.0-10.0 and at the temperature of 60 degrees C. Estimated by Lineveaver-Burk plots, the K(m) of the enzyme was 3.1 mmol/L. Ag+, Hg2+, SDS and Tween 80 dramatically inhibted the enzyme activity, whereas Tween 20 and Triton X-100 had no effect on enzyme activity. The thermostability of this enzyme was better than reported sarcosine oxidases, and it could be applied in enzymatic measuring of creatinine.

Gene gyrA Mutation in Nalidixic acid-resistant Salmonella paratyphi A / 中华医院感染学杂志

OBJECTIVE To explore the gene gyrA mutation in nalidixic acid-resistant Salmonella paratyphi A(SPA) in Shaoxing area.METHODS Fifty-two strains of SPA gene were assessed by amplification and purification and the PCR products were detected by two directional sequencing methods.The sequences of DNA gyrase A were compared and analyzed with the OMIGA2.0 software,and the gene gyrA mutation was identified.RESULTS The mutation in nalidixic acid-resistant SPA was discovered in No.83 or No.87 animo acid site of gyrA quinolones resistant determinate region(QRDR),and the mutation of 51 strains occurred in No.83 site,1 strain occurred in No.87 site.The simultaneous mutation of two sites was not discovered,No mutations were found in other sites of gyrA QRDR.CONCLUSIONS No.83 site mutations of gene gyrA has a direct relation to nalidixic acid-resistant SPA.No.87 site mutation of gene gyrA might also cause nalidixic acid-resistantce.The nalidixic acid-resistant SPA is mainly mutated in No.83 site by TCC→TTC(Ser→Phe) in Shaoxing area.

Neuroprotective effect of lateral ventricle infusion of low-temperature fluid following focal cerebral ischemia-reperfusion in rabbits / 中国组织工程研究

BACKGROUND: Neuroprotective role of hypothermia on cerebral ischemic-reperfusional impairment has been long acknowledged. Since general hypothermia is complicated and unfit for observing postoperative consciousness and neurological function, it is of important significance to explore novel methods of focal cerebral hypothermia.OBJECTIVE: To study the neuroprotective effect of lateral ventricle infusion of low-temperature fluid on ischemic neurons of middle cerebral artery (MAC) occlusion models established on New Zealand rabbits.DESIGN: A randomized case-control study based on experimental animal models.SETTING: Neurosurgical department and pathological department of a general military hospital of Chinese PLA.MATERIALS: This study was carried out at Neurosurgical Laboratory of Nanjing General Hospital, Nanjing Military Area Command of Chinese PLA. Altogether 18 healthy New Zealand male rabbits, weighing from 2. 8 to 3.2 kg, were selected 4 - 6 months after birth, and randomly divided into occlusion group, hypothermia group and control group.INTERVENTIONS: Cerebral focal ischemic-reperfusional model was established on the New Zealand rabbits through MCA occlusion for 2 hours followed by reperfusion for 24 hours.MAIN OUTCOME MEASURES: Scores for neurological function, water content in the left and right brain, pathological changes of nerve cells in the left MCA supplying region.pothermia group, significantly higher than that in occlusion group(7.58 ± 0.58 )( P ＜ 0.01 ), but no significant difference could be observed in contrast with brain was(81.64 ± 0.82)% and (79.26 ± 1.30)% in occlusion and hypothermia groups with significant difference between them( P ＜ 0.05), and it was significantly different between the left side [ (81.64 ± 0. 82 )% ] and opyknosis and deep staining could be observed in nerve ganglion cells in occlusion group under optical microscope, but no obvious pathological changes were observed in MCA supplying brain regions in hypothermia group.CONCLUSION: Permanent infusion of low-temperature fluid into the lateral ventricle plays an important neuroprotective role by attenuating cerebral ischemic-reperfusional impairment and improving post-ischemic neurological functions.

Effects of hypothermia within the lateral ventricle on the neural cell apoptosis after rabbit cerebral ischemia / 医学研究生学报

Objective: To explore the effects of continuous trickle of low temperature liquids through the lateral ventricle on neural cell apoptosis after rabbit local cerebral ischemia/reperfusion. Methods:The middle cerebral artery (MCA) of New Zealand rabbit was clipped by micro aneurysm clip for 2 hours and reperfused for 24 hours. Immediately after clipping the MCA, we trickled the left lateral ventricle continuously with low temperature liquids(22℃) to decrease the brain temperature to mild hypothermia (33℃-35℃)and maintained for 2 hours. After reperfusion for 24 hours , we assessed TUNEL method to determine the apoptotic cell rate in the sham-operated group, the control group and the mild hypothermia group respectively. Results:The apoptotic cell rate of the cortex tissues accommodated by MCA in the mild hypothermia group was obviously lower than that in the control group(P0.05). Conclusion:Trickling ventricle with low temperature liquids could decrease the apoptotic cell rate and alleviate cerebral ischemia/reperfusion injury.

Ultrastructural observation of the stratum corneum lipids in hairless mouse epidermis characterized by ruthenium tetroxied fixation / 医学研究生学报

Objectives: To reveal the morphological features of the stratum corneum lipids in hairless mouse epidermis. Methods: Ruthenium tetroxide and osmium tetroxide were compared as post fixative in the preparation of hairless epidermis for transmission electron microscopic examination. Results: Both reagents reveled characteristic membrane coating granules within the granular layer. Whereas, the transformation of the membrane coating granule contents into multiple lamellae at the interface between the granular and cornified layers and the persistence of these lamellae through all levels of the stratum corneum were demonstrated only by ruthenium tetroxide fixation. Conclusions: The distinctive patterning of the intercellular lamellae reflects the nonrandom organization of the stratum corneum lipids. In addition, the ruthenium tetroxide postfixation technique is a useful method in the investigation of the morphological features of the stratum corneum lipids.

Effect of low temperature liquids trickled through the lateral ventricle on brain protection after rabbit local cerebral ischemia-reperfusion injury / 医学研究生学报

Objectives:To explore the protective effects of continuous trickle of low temperature liquids through the lateral ventricle on neurons after rabbit local cerebral ischemia reperfusion. Methods: The middle cerebral artery (MCA) of New Zealand rabbit was clipped with micro aneurysm clip for 2 hours and reperfused for 24 hours. Immediately after clipping the MCA, we trickled the left lateral ventricle continuously with low temperature liquids to decrease the brain temperature to mild hypothermia(32-35℃) and maintained for 2 hours. After reperfusion for 24 hours, we assessed the animal's neural deficits, observe the pathology of the ischemic brain tissues dyed by HE and determined the dry wet ratio for brain edema in the sham operated group, the control group and the mild hypothermia group respectively.Results:①The grades of neural deficits in mild hypothermia group were obviously lower than that in the clipping group( P 0.05 );②The dry wet ratios were obviously different in the mild hypothermia group and clipping group;③ Pyknosis and dense dying by HE were observed in the neural nuclei of ischemic cortex tissues of the clipping group, but no obvious changes were observed in the mild hypothermia group. Conclusions:Trickling ventricle with low temperature liquids could alleviate cerebral ischemia reperfusion injury, ameliorated neural deficit after ischemia reperfusion and were protective on the brain.

The relationship between angiogenesis,proliferation and lymph node metastasis in rectal cancer / 医学研究生学报

Objectives:To study the relationship between angiogenesis,proliferation and lymph node metastasis in rectal cancer. Methods: Forty six rectal cancer specimens were examined immunohistochemically. The intratumor microvessel density(MVD), vascular endothelial growth factor (VEGF)expression positive rate and Ki 67 label index(Ki 67 LI) were detected and their relationship with tumor invasion and lymph node metastasis were analyzed. Results: The MVD, VEGF expression positive rate and Ki 67 LI increased significantly( P

Prognostic value of the somatostatin receptor expression in human primary breast invasive ductal carcinoma / 医学研究生学报

Objective: To investigate the relationship of the expression of the somatostatin receptor(SSTR) with tumor stages,tumor differentiation and the survival time in patients with human primary breast invasive ductal carcinoma(HPBIDC) and to provide theoretical evidence for the diagnosis,prognosis and treatment of the disease based on the SSTR expression.Methods: We detected the SSTR expression in the tumor tissues of 82 HPBIDC patients,and analyzed the relationship of the SSTR expression with the prognosis and survival time of the patients.Results: In the HPBIDC patients,the 5-year overall survival(OS) rates of the negative,weakly positive,moderately positive and strongly positive SSTR expression groups were 59.1,76.2,85.2 and 100.0%,those of the well,moderately and poorly differentiated groups were 94.1,90.6 and 60.0%,and those of the TNM Ⅰ,TNM Ⅱ,TNM Ⅲ and TNM Ⅳ groups were 100.0,86.0,56.3 and 25.0%,respectively.Conclusion: The expression of SSTR is significantly correlated with the prognosis of human primary breast invasive ductal carcinoma.

Healing mechanism of intestinal anastomosis in intra-abdominal sepsis rats / 医学研究生学报

Objective: To investigate the mechanism of intestinal anastomosis in a rat model of intra-abdominal sepsis.Methods:Male Wistar rats were randomized into 2 groups.Control rats underwent intestinal anastomosis.Sepsis group underwent intestinal anastomosis after intestinal fistula operation.fibronectin(FN),?-smooth muscle actin(?-SMA),vascular endorthelial growth factor(VEGF) and apoqtosis in anastomoses were measured.Results:FN,?-SMA,VEGF in control group were higher than sepsis group and apoptosis were lower than the other.Conclusion:It is indicated that the repair of tissue was out of balance after infection,and the organization repair was retarded.The collagenoblast and the epithelial cell migration were slowed down,and the blood capillary regeneration was slowly.Not only the granulation organization was reduced,but also apoptosis was prematurely appeared.

Expression of somatostatin receptor in primary invasive ductal carcinoma of breast / 医学研究生学报

Objective: To determinate whether human primary breast invasive ductal carcinoma((HPBIDC)) express somatostatin receptor(SSTR). Methods: SSTR expression in 82 patients with invasive duct carcinoma of breast was determined by immunohistochemistry and its correlation with clinical and pathological facts was analysed. Results: IHC analyses revealed that SSTR was expressed in HPBIDC (61/82, 74.4%). A significant correlation was found between SSTR expression and tumor stage (P

A clinicopathological and prognostic study of 22 cases central neurocytoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the clinicopathological features and prognosis of 22 cases of central neurocytoma (CNC), representing 0.48% of a series of 4 528 patients undergoing biopsy for central nervous system tumors.</p><p><b>METHODS</b>The histopathological, ultrastructral, immunohistochemical and clinical features of CNC were studied by electron microscopic examination and immunohistochemical stain for Synaptophysin (Syn), neuron special enolase (NSE), Leu-7, glial fibrillary acid protein (GFAP), MBP and proliferating cell nuclear antigen (PCNA).</p><p><b>RESULTS</b>The age of the cases ranged from 4 to 44 (average 27.9 years) with all tumors localized in the ventricles. In the 18 patients followed up, 14 were alive for 8 months to 14 years and 11 months after the operation, and 4 died. The average survival period was 70.7 months. Histologically, the tumor in all 22 cases had the oligodendroglioma-like pattern with honeycomb appearance and cell-free islands of eosinophilic matrix. Cellular anaplasia, mitosis and necrotic areas were rarely seen in the tumors. Immunohistochemical study demonstrated strong positivity for Syn, NSE and Leu-7, and negative for GFAP and MBP. Ultrastructural features showed presence of round tumor cells with abundant cell processes containing microtubules, neurosecretory granules, clear vesicles and lysosome-like structures.</p><p><b>CONCLUSIONS</b>The differential diagnosis between CNC and oligodendroglioma could not be established by routine light microscopy. The importance of immunohistochemical and electron microscopic studies for making a correct diagnosis is emphasized. The prognosis of patients is usually favorable, even if the tumor was resected subtotally. The relationship between the presence of anaplastic histological features in CNC and patient outcome remains unclear.</p>

The expression of thyroid transcription factor-1 in pulmonary sclerosing hemangioma and a further investigation on histogenesis of the tumor / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the histogenesis and pathologic features of pulmonary sclerosing hemangioma (SH) and its expression of thyroid transcription factor-1 (TTF-1).</p><p><b>METHODS</b>Seventeen cases of pulmonary sclerosing hemangioma were reevaluated and 12 cases were immunostained with a panel of antibodies including TTF-1, EMA, cytokeratin, etc. Six cases were studied by electron microscopy.</p><p><b>RESULTS</b>All cases exhibited the classic histologic features with variable proportions of solid, papillary, hemorrhagic or hemangiomatic, and sclerotic pattern. The tumours consisted of solid sheets or aggregates of pale polygonal cells and papillae and clefts lined by cuboidal or columnar cells. Both TTF-1 and EMA expressions were observed in the surface lining cuboidal cells and the pale polygonal cells. In only one case both chromogranin and synaptophysin showed weakly positive in few polygonal cells and a small number of granules with high electron density was found in the polygonal cells by electronic microscopy.</p><p><b>CONCLUSIONS</b>It is suggested that pulmonary sclerosing hemangioma is an epithelial neoplasm derived from primitive respiratory epithelium capable of differentiating toward pneumocytes or Clara cells. The immunohistochemical markers such as TTF-1, EMA and CK play an important part in diagnosis of SH.</p>

Clinicopathological studies of extraovarian peritoneal serous papillary carcinoma / 医学研究生学报

Objectives:To study the clinicopathological features of extraovarian peritoneal serous papillary carcinoma.Methods:The clinical pictures and pathological characteristics of 6 cases extraovarian peritoneal serous papillary carcinoma admitted to our hospital from 1992 to 1999 were studies retrospectively.H & E staining,histochemical staining and immunohistochemical staining were used.Results:The ages of the 6 patients were between 32～62(43.7) years old.The bilateral ovaries and fallopian tubes were almost normal.Tumors were examined histomorphologically by microscope and electron microscope,periodic acid-Schiff (PAS) stain was used in the histochemical study and carcinoembryonic antigen (CEA),CA125,p53,AE1 and AE3 monoclonal antibody assays were detected immunohistochemically.The results revealed no difference between extraovarian peritoneal serous papillary carcinoma and ovarian serous papillary carcinoma.Conclusions:Extraovarian peritoneal serous papillary carcinoma is considered arising from the secondary Müllerian system.Histologically,extraovarian peritoneal serous papillary carcinoma was identical to that of the similar epithelial carcinomas arising from the ovaries.The diagnosis was made only when the ovaries were not involved and without any evidence of similar epithelial carcinoma obtained in the ovaries.Histochemical staining and immunohistochemical staining are helpful as accessory criteria for the differential diagnosis between primary carcinoma of the peritoneum and malignant mesothelioma.The prognosis is poor.

Changes of angiogenesis in rectal cancer patients after preoperative radiotherapy / 中国普通外科杂志

Objective To explore the effect of preoperative radiotherapy on angiogenesis of rectal cancer. Methods Twenty patients with advanced lower rectal carcinoma received preoperative radiation with a dosage of 30～40 Gy each time for a total of 15～20 sessions during a period of 3～4 weeks. The definitive surgery was performed 7～10 days after radiotherapy. Another 20 patients undergoing tumor resection without preoperative radiotherapy served as control. Tumor sample was sent for pathology. The expression of vascular endothelial growth factor (VEGF) and CD34 in the rectal cancer were detected immunohistochemically. The intratumoral microvessel density (MVD) was measured. Results Fifteen patients were found with grade Ⅱ and five patients with grade Ⅲ tissue response in radiotherapy group. The diameter of intratumoral microvessel was smaller in radiotherapy group than in control group( P

Healing mechanism of growth hormone and fibrin glue on intestinal anastomosi in intra-abdominal sepsis rats / 肠外与肠内营养

Objective: To investigate the mechanism of combined growth hormone and fibrin glue on early healing of intestinal anastomosis in intra-abdominal sepsis rats.Methods: Male Wistar rats of abdominal sepsis were randomized into 3 groups.Control rats were given intestinal anastomosis after intestinal fistula operation.Glue group was given intestinal anastomosis and fibrin glue after intestinal fistula.GH group was given intestinal anastomosis and fibrin glue and growth hormone after intestinal fistula.FN,?-SMA,VEGF,and apoptosis in anastomoses were measured.Results: Expression of intestinal FN,?-SMA,and VEGF in GH group were higher than those in other groups and apoptosis were lower than others.Conclusion: It is indicated that combined growth hormone and fibrin glue ameliorates healing of intestinal anastomosis in intra-abdominal sepsis rats.

Cervical Lymphadenitis Caused by Candida albicans:A Case Report / 中华皮肤科杂志

Objective To report the first case of cervical l ymphadenitis caused by Candida albicans in China.Methods A series of clinical,histopatholog ic.and mycologic studies were carried out in an 8year-old-boy with cervical lymphadenitis,who had no definite underlying disease.Candida albicans was isolated fromthe patient.The lymph node was investigated by me ans of culture,pathological and tra nsmission electron microscopic examination and cellular immunology detected by flow cytometer.Results There were several enlarged,warm,a nd fluctuant cervical lymph nodes which varied fr om 1cm?1cm to 4cm?4cm in size.One swo llen node was excised,and Candida albicans was found in the culture.The histopathologic changes of the cervical lym ph node were compatible with chronic granulomatous disease.PAS and methenamine silver(PAM)stain of a touch preparation of the bi opsy specimen revealed budding spores an d pseudohyphae.Lymphopenia with a p roportionate decrease of T-helper a nd T-suppressor cells was shown with flowcytometry.The patient received a combination therapy of surgery,flu conazole,thymosin and so on.After one month,t he patient's condition was improved.Many small lymph nodes disappeared,large lymph nodes became smaller.Tw o months later,only one large lymph n ode could be touched.Conclusion It is the first case of cervical lymphad enitis caused by Candida reported in China.Combination therapy of surgery,fluconazole and thymosin is effective.