鼠疫菌9.5kb质粒对假结核菌粘附、侵袭上皮细胞能力的影响

用电穿孔方法把克隆的鼠疫菌９．５ｋｂ质粒转移到不同血清型的假结核菌中，研究了不同实验条件下９．５ｋｂ质粒对假结核粘附、侵袭上皮细胞（Ｈｅｐ－２）能力的影响。结果显示，尽管９．５ｋｂ质粒不能明显改变假结核菌的粘附、侵袭特征，但相对于亲本株而言，转化后的菌体在所有实验条件下侵袭上皮细胞的能力确定有所下降，表明９．５ｋｂ质粒介导的粘附、侵袭机制有别于假结核菌。由此，分析和评价了９．５ｋｂ质粒在粘附、侵袭     

Genome sequencing in a genetically elusive multigenerational long QT syndrome pedigree identifies a novel LQT2-causative deeply intronic KCNH2 variant

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Comparative analysis of cancer-associated antigen CA-195, CA19-9 and carcinoembryonic antigen in diagnosis,follow-up and monitoring of response to chemotherapy in patients with gastrointestinal cancer

Summary To establish further the clinical significance of the CA-195 tandem immunoradiometric assay in gastrointestinal malignancies, the sera of a total of 222 subjects have been analysed and compared with assays of the classical gastrointestinal tumour markers, CA19-9 and carcinoembryonic antigen (CEA). CA-195 elevations above normal (>10 U/ml) were noted in 51/72 (70.8%) colorectal, 15/15 (100%) pancreatic, and in 6/12 (50%) gastric cancer patients. Whereas CA19-9 was increased (>37 U/ml) in 65%, 93%, and 42% of cases, only 54% colorectal, 45% pancreatic, and 42% gastric cancer patients had pathologically elevated serum CEA levels (>5 ng/ml). No abnormal increase of both CA-195 and CA19-9 was found in healthy volunteers, whereas 3/20 (smoking) individuals had CEA levels slightly above normal. With a 29% false-positive rate noted among 103 patients with benign gastroinestinal disorders, the specifity of CA-195 was superior to that of CA19-9 (58%) and comparable with that of CEA (31%). A significant correlation between CA-195 levels and the clinical/pathological stage of disease was noted in colorectal (P<0.01) and pancreatic cancer patients (P<0.007). Preliminary results of serial measurements of CA-195 in colorectal cancer suggest that this new marker protein, which has no cross-reactivity with CEA, may be useful as a non-invasive test for postoperative surveillance of patients to detect disease recurrence, and serve to complement (though certainly not replace) standard clinical measurements of response to chemotherapy.Abbreviation CEA carcinoembryonic antigen     

Screening of diabetic retinopathy: effect of field number and mydriasis on sensitivity and specificity of digital fundus photography

PURPOSE: To evaluate the sensitivity and specificity of one- and three-field, nonmydriatic and mydriatic, and 45 degrees digital colour photography compared with mydriatic indirect ophthalmoscopy for diabetic retinopathy (DR) screening. METHODS: A group of 79 patients (158 eyes) were included in this prospective study. Colour fundus photographs were taken with a Topcon TRC-NW6S digital camera, using four different techniques--single-field nonmydriatic; three-field nonmydriatic; single-field mydriatic; and three-field mydriatic--followed by dilated ophthalmoscopy. Two independent ophthalmologists classified blinded photographs according to the presence or absence of specific diabetic retinal findings. The sensitivity, specificity and agreement (kappa analyses) of the four methods were calculated for the presence or absence of DR and for all diabetic retinal findings. RESULTS: The sensitivity and specificity of digital photography compared with ophthalmoscopy for detection of DR were, respectively: 77 and 99% using single-field nonmydriatic; 92 and 97% using three-field nonmydriatic; 90 and 98% using single-field mydriatic; 97 and 98% using three-field mydriatic. The degrees of agreement for the four methods were 0.82, 0.90, 0.90 and 0.95, respectively. For specific retinal findings, sensitivity was greater for detection of hard exudates, nerve fibre layer haemorrhage and venous beading, and lower for detection of microaneurysms, dot-blot haemorrhage, cotton wool spots and intraretinal microvascular anomalies. CONCLUSION: The three-field strategy without pupil dilation represents a good compromise, with reasonable sensitivity and good comfort (short examination duration, able to drive after photography) favouring patient compliance with the screening programme.     

TB, HIV-associated TB and multidrug-resistant TB on Thailand's border with Myanmar, 2006-2007

Objective To measure the burden and improve management of tuberculosis (TB), HIV‐associated TB and MDR TB in Tak Province, Thailand, which borders Myanmar. Methods From September 2006 to August 2007, we collected uniform data about TB cases and enhanced human immunodeficiency virus (HIV) counselling and testing. We provided mycobacterial culture and drug‐susceptibility testing in public or non‐governmental organization facilities. Patients were classified by nationality and, for non‐Thais, by migration status. Results Of 1662 TB cases in the 12‐month period, 1087 (65%) occurred in non‐Thais. Of non‐Thais, 415 (38%) lived in Myanmar but crossed the border for healthcare. HIV infection was diagnosed in 18% of Thais compared with 12% of non‐Thais (P < 0.01); HIV status was unknown for 22% of Thais and 27% of non‐Thais (P = 0.02). Overall, multidrug‐resistant (MDR) TB was diagnosed in 27 patients, 19 (70%) in non‐Thais. Among TB cases never previously treated for TB, no MDR cases were diagnosed in Thais or in Myanmar refugees, but six cases were diagnosed in migrants from Myanmar. Conclusions In Thailand, TB, HIV‐associated TB and MDR TB in migrants from Myanmar are important public health problems; they need to be resolved in both the countries.     

Immunohistochemical study of colorectal adenocarcinomas and adenomas with antibodies against carcinoembryonic antigen (CEA), CA19-9, keratin, α-tubulin and secretory component (SC)

The immunohistochemical localization of five antibodies against carcinoembryonic antigen (CEA), CA19-9, keratin, α-tubulin and secretory component (SC) was investigated in 14 lesions of adenocarcinoma (AC), 22 of adenoma with high-grade atypia (AH), 50 of adenoma with low-grade atypia (AL), and 15 of non-neoplastic mucosa (NNM) of the large intestine. The positive patterns for each staining were divided into three categories (patterns 1,2, and 3). All neoplastic lesions (AC, AH and AL) were positive for CEA, while 85.7% of AC, 36.4% of AH and 6.0% of AL showed strongly positive staining (pattern 3). 78.6% of AC and 54.5% of AH were positive for CA19-9 in comparison to 20.0% of AL. For keratin, more than 95% ofthe neoplastic lesions were positive, while 78.6% of AC, 27.3% of AHand 22.0% of AL showed strongly positive staining (pattern 3). For a-tubulin, more than 85% of neoplstic lesions were positive, while 50.0% of AC, 36.3% of AH and 26.0% of AL showed strongly positive staining (pattern 3). For SC, in contrast, 42.9% of AC, 27.3% of AH and 8.0% of AL were negative, but 93.3% of NNM were positive. It was concluded that the positive staining rate, especially the rate of pattern 3 for each antibody correlated with the degree of atypia of the colorectal neoplastic lesions (AC, AH and AL).     

Serum and cystic fluid CA 19–9 determinations as a diagnostic help in liver cysts of uncertain nature

Abstract: The distinction between hepatobiliary cystadenoma or cystadenocarcinoma and simple hepatic cyst complicated by intracystic hemorrhage may prove difficult to determine on the sole basis of clinical and radiological features because of the presence of intracystic structures and septations well-demonstrated by ultrasound examination in both situations. We investigated four patients with various types of hepatic cysts, in whom diagnostic difficulties led to further investigations. In this small group, CA 19–9 serum levels were abnormal only in the two patients with cystadenoma or cystadenocarcinoma. Cystic fluid CA 19–9 values were also five times higher in cystadenoma and cystadenocarcinoma than in other benign lesions. Our data thus suggest that the determination of serum and cyst fluid CA 19–9 may be of help in distinguishing between hemorrhagic simple cyst and cystadenoma or cystadenocarcinoma.     

Cas9-expressing chickens and pigs as resources for genome editing in livestock

Genetically modified animals continue to provide important insights into the molecular basis of health and disease. Research has focused mostly on genetically modified mice, although other species like pigs resemble the human physiology more closely. In addition, cross-species comparisons with phylogenetically distant species such as chickens provide powerful insights into fundamental biological and biomedical processes. One of the most versatile genetic methods applicable across species is CRISPR-Cas9. Here, we report the generation of transgenic chickens and pigs that constitutively express Cas9 in all organs. These animals are healthy and fertile. Functionality of Cas9 was confirmed in both species for a number of different target genes, for a variety of cell types and in vivo by targeted gene disruption in lymphocytes and the developing brain, and by precise excision of a 12.7-kb DNA fragment in the heart. The Cas9 transgenic animals will provide a powerful resource for in vivo genome editing for both agricultural and translational biomedical research, and will facilitate reverse genetics as well as cross-species comparisons.

Chickens and pigs are the most important livestock species worldwide. They are not only important sources of food, but also valuable models for evolutionary biology and biomedical science. Pigs share a high anatomical and physiological similarity with humans and are an important species for translational biomedical research, for example, in the areas of cancer, diabetes, neurodegenerative, and cardiovascular diseases (1–3). They also resemble the human pathophenotype more closely than rodents. For example, pig models for familial adenomatous polyposis (FAP) develop polyps in the large intestine as observed in human patients (4), whereas mouse FAP models develop them in the small intestine (5). In contrast to mammals, chickens are phylogenetically distant vertebrates from humans, but they were instrumental in the field of developmental biology due to the easy access to the embryonated egg. They are used for studying neurological and cardiovascular functions (6–8) and provided key findings in B cell development and graft versus host responses (9–11). Genetically modified livestock species also hold great promise for agriculture by offering new approaches for disease control, such as genome-edited pigs resistant to Porcine Reproductive and Respiratory Syndrome or Avian Leucosis Virus (ALV)-resistant chickens (12–15).Due to the lack of fully functional embryonic stem cells, genetic engineering in pigs and chickens has been a laborious, inefficient, and time-consuming procedure (16). The generation of pigs with precise germline modifications required gene targeting in somatic cells followed by somatic cell nuclear transfer. This also is not practical in chickens, where precise alteration of the genome only became possible with recent improvements in the cultivation and manipulation of germline-competent primordial germ cells (PGCs) (17–19). These modified PGCs can be injected into the blood vessel system of stage 13 to 15 (Hamburger−Hamilton [HH]) embryos to produce germline chimeras and, by further breeding, genetically modified chickens.With the advent of synthetic endonucleases such as CRISPR-Cas9 efficiency of targeted germline modification has improved in both species (20–23). It still requires the generation and breeding of new founder lines, which is time consuming in large animals. To circumvent the need for generating germline-modified animals, attempts have been made to carry out genome editing directly in specific organs or tissues (24–27). But this has been hampered by the need to deliver both Cas9 and the required guide RNA (gRNA) and by the limited cargo capacity of viral vectors. To bypass this drawback, Cas9 transgenic mice have been generated, requiring delivery of only the respective gRNAs (28).Here, we describe the generation of both Cas9 transgenic pigs and chickens that ubiquitously express Cas9 endonuclease and provide proof of its function in vitro and in vivo. These animals provide an innovative and efficient model for in vivo genome editing to assess gene function in health and disease.     

Liver‐infiltrating CD56 positive T lymphocytes in hepatitis C virus infection

Abstract: Aim: Hepatitis C virus (HCV) is a major cause of post‐transfusional and sporadic hepatitis, and leads to chronic liver disease. It has been suggested that virus‐specific cytotoxic T lymphocytes are responsible for liver injuries that occur in HCV‐infected patients. However, the detailed characteristics of these lymphocytes have not yet been defined. We have previously reported that CD56⁺ T lymphocytes, as intermediates between natural killer cell and T lymphocytes, predominantly infiltrated the liver and were increased in patients with chronic hepatitis related to HCV (CH‐C). Material and Methods: We obtained peripheral blood and liver tissues from 32 patients diagnosed as having CH‐C, and 10 other liver disease patients (5 chronic hepatitis related to HBV, 5 alcoholics), and analyzed peripheral blood and liver‐infiltrating lymphocytes using flow cytometric and immunohistochemical techniques. Results: The CD56⁺ T lymphocyte ratio in the liver of patients with a high histology activity index (HAI) score for chronic hepatitis was higher than that of patients with a low HAI score and patients with other liver diseases. In addition, T lymphocytes from patients with chronic hepatitis with a high HAI score carried mostly γδ‐TCR. There was a correlation between the ratio of CH‐C and serum alanine aminotransferase, category I (periportal inflammation and necrosis), and IV (fibrosis) of the HAI scoring system. The ratio was highest in zone 1 of the hepatic lobules. Conclusion: The correlation between CD56⁺ T lymphocyte ratios and hepatocellular damage was examined. These findings suggest strongly that liver‐infiltrating CD56⁺ T lymphocytes play an important pathologic role in hepatocellular injury in CH‐C.     

Clinical significance of tumor marker NCC-ST 439 in large bowel cancers

We examined serum NCC-ST 439 for its significance as a tumor marker of large bowel cancer in 121 patients with primary and 36 with recurrent large bowel cancer. Serum NCC-ST 439 was positive in 27.3 percent of the former and 66.7 percent of the latter. It was false-positive in only 5.6 percent of patients with benign diseases. Positive serum NCC-ST 439 correlated with lymph node and liver metastases. The combination assay for NCC-ST 439, CEA, and CA19-9 was positive in 49.6 percent of the patients with primary tumors and 88.9 percent of those with recurrent tumors; in other words, the diagnostic accuracy improved. The results demonstrated that the determination of serum NCC-ST 439 in large bowel cancer might be useful in cancer staging and that NCC-ST 439, if used in combination with CEA, is particularly useful in diagnosing recurrences because of its improved diagnostic accuracy.