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Gamma-ray bursts (GRBs) are the most intense explosions in the Universe. GRBs with extended emission (GRBs EE) constitute a small subclass of GRBs. GRBs EE are divided into EE-I GRBs and EE-II GRBs, according to the Amati empirical relationship rather than duration. We test here if these two types of GRB have different origins based on their luminosity function (and formation rate). Therefore, we use Lynden-Bell's c − method to investigate the luminosity function and formation rate of GRBs with EE without any assumption. We calculate the formation rate of two types of GRBs. For EE-I GRBs, the fitting function can be written as ρ(z) ∝ (1 + z)−0.34 ± 0.04 for z < 2.39 and ρ(z) ∝ (1 + z)−2.34 ± 0.24 for z > 2.39. The formation rate of EE-II can describe as ρ(z) ∝ (1 + z)−1.05 ± 1.10 for z < 0.43 and ρ(z) ∝ (1 + z)−8.44 ± 1.10 for z > 0.43. The local formation rate is |$\rho (0) = 0.03\, {\rm Gpc}^{-3} \, {\rm yr}^{-1}$| for some EE-I GRBs and |$\rho (0) = 0.32 \, {\rm Gpc}^{-3} \, {\rm yr}^{-1}$| for EE-II GRBs. Based on these results, we provide new evidence that the origins of EE-I GRBs are different from EE-II GRBs from the perspective of event rate. The EE-I GRB could be produced from the death of the massive star, but EE-II GRB may come from other processes that are unrelated to the star formation rate. Our findings indicate that the GRBs with EE could have multiple production channels. [ABSTRACT FROM AUTHOR]

Retrotransposons are the most widespread class of eukaryotic transposable elements and play an important role in genome evolution. Several of these elements have been sequenced and were found to contain different cis-regulatory elements involved in the response to different stress conditions in their long terminal repeat sequences (LTRs). Retrotransposon-based marker systems have proved useful because of their distribution, ubiquity, and prevalence in plant genomes. Here we report on the isolation and characterisation of new RNaseH-LTR sections of the Tyl-copia-like retro-elements in apple DNA. Twenty clones were identified with a variable degree of homology to the Tyl-copia RNaseH gene. Nineteen had the characteristic RNaseH gene, stop codon, polypurine tract (PPT), and putative 3'-LTR sequence elements. The RNaseH sections were aligned using ClustalV to seek potential relationships between sequences. This analysis revealed six distinct Clusters. Conserved motifs, corresponding to cis-regulatory elements, were discovered in the LTRs using plantCARE software and four were characterised. From one putative LTR fragment, we then designed a primer, which, through sequence-specific amplification polymorphism (S-SAP), could distinguish between 'Wellspur Delicious', 'Hardispur Delicious' and 'Starkrimson', and 'Starking' apple, by fingerprinting. The first three varieties originated from 'Starking' through bud mutations. Our results suggest that these bud mutations appeared to have been derived from retrotransposon insertions. [ABSTRACT FROM AUTHOR]

We report a new strategy for the generation of human anticolon cancer monoclonal antibodies based on the molecular cloning and expression of immunoglobulin variable region cDNAs derived from peripheral blood mononuclear cells (PBMC) that were transformed by EBV. The immortalized B cells secreting tumor-specific antibodies were identified by HRT-18 cell ELISA and cloned by limiting dilution. Heavy- and light-chain VH-CH1 (gamma) and V kappa-C kappa cDNAs were rescued from ELISA-positive cells wells by RT-PCR. VH and V kappa were amplified by 2nd PCR and linked them together by 3rd PCR assembly with the use of a (Gly4Ser)3 linker. The ScFv cDNAs were then cloned into the fUSE 5 vector and displayed on phage. Phage clones were selected on HRT-18 cells and normal human PBMC. ELISA tested phage clones randomly picked after each panning step. > 80% of the clones showed a strong ELISA reaction, demonstrating the effectiveness of the panning procedure for selecting anticolon cancer antibodies. This approach offers an effective method by combining in vitro immunization, B-cell expansion for enrichment of specific B-lymphocytes, PCR gene cloning and phage display to make high-affinity human anticolon cancer monoclonal antibody molecules.

We prepared anti-idiotypic monoclonal antibodies (Ab2) against FC2 and HNL5 that recognized as nasopharyngeal cancer (NPC) associated antigens. These Ab2, which designated as 2H4 and 5D3, could inhibit the binding of FC2 or HNL5 to NPC cell lines. The anti-sera from the immunized mice that contained anti-anti-idiotype antibodies (Ab3) could compete with FC2 or HNL5 for binding with NPC cell by a competitive inhibition assay. When 2H4 or 5D3 immunized mice coupled with keyhole limpet hemocyanin(KLH), positive and specific delayed-type hypersensitivity (DTH) reaction occurred after the mice were stimulated by NPC cells. The proliferative response of the splenocytes was significantly higher in experimental groups than that in control groups. Therefore, it is suggested that the anti-idiotypic antibodies (Ab2) 2H4 and 5D3 are the Ab2 beta bearing the internal image of the epitope of NPC associated antigen, that either 2H4 or 5D3 expressing three dimensional shapes which resemble the structure of natural antigens can induce humoral and cellular immune response.

This is a collective review of 564 patients with Marfan syndrome among 98 pedigrees reported from 18 provinces and cities in China over a 37-year period from 1951 to 1987. A positive family history of Marfan syndrome was found in 74.3% of the patients: the mode of inheritance was dominant in 73.8% and recessive in 0.5%. Sporadic cases occurred in 25.7%. A screening of 29,067 children found five children with Marfan syndrome, giving a prevalence of 17.2 per 100,000 of the population, a gene frequency of 8.61 per 100,000 genes, and a penetrance of 71.69%. Pleiotropy was clear in these cases: arachnodactyly in 77%, ectopia lentis in 86.8%, and dilated aortic root in 80.1%. Chromosome examination showed no regular aberrations except in a family of five in whom a giant-satellited chromosome 14 was found in three afflicted members but not in the two unaffected relatives. The high prevalence of aortic root dilation in Marfan syndrome makes echocardiography the most useful and practical means of diagnosis. Close follow-up and regular echocardiographic evaluation are indicated not only in patients with Marfan syndrome but also in their families, for both diagnostic and therapeutic purposes.

Plasma fibronectin concentrations were measured in 78 patients with traumatic fracture and 80 healthy people as a control. The results showed that plasma fibronectin concentrations of the patients without complicated infection were significantly decreased 5 to 48 hours after fracture. As comparison with the control, the mean decrease was 56 (16.9%; P less than 0.01), 121 (36.5%; P less than 0.001) and 71 mg/L (21.4%; P less than 0.001) at 5.24 and 48 hours respectively, and restored to the levels of the control at 4 days. In the patients complicated infection, plasma fibronectin concentration was not recovered at 14 days after fracture. The mean decrease was 96 (28.9%; P less than 0.001); 148 (44.6%; P less than 0.001), 119 (35.8%; P less than 0.001), 83 (25.0%; P less than 0.001), 59 (17.8%; P less than 0.01) and 43 mg/L (13.0%; P less than 0.01) at 5.24, 48 hours, 4.7 and 14 days, respectively, as comparison with the control. The results suggest that plasma fibronectin concentrations in the patients with fracture without complicated infection are temporarily decreased and rapidly recovered, but, in the patients with complicated infection, the low fibronectin levels are continued and render the patients more susceptible for bacteria and thus result in complicated infection. Plasma fibronectin can be used as a valuable index to prevent and treat complicated infection after traumatic fracture.

The LeY determinant, a difucosylated type 2 blood group-related antigen, is a positional isomer of the Leb blood group antigen and a fucosylated derivative of the LeX antigen. The LeX antigen behaves like an oncodevelopmental tumor-associated antigen in human colon cancer, and extended polyfucosyl LeX antigens are more specific for colon cancer tissues than are simple, monofucosyl LeX antigens. The present investigation compared the expression of simple and extended LeY antigens in a variety of malignant and nonmalignant human colonic tissues to gain insight into the normal distribution and cancer-associated expression of these antigens. Monoclonal antibody AH-6, which recognizes the LeY epitope irrespective of its carrier carbohydrate chain, stained the majority of specimens regardless of malignant potential or location within the colon. In contrast, CC-1 and CC-2 monoclonal antibodies, which recognize extended LeY structures, and KH-1, which is specific to trifucosyl LeY, preferentially stained malignant colonic tissues and rarely stained normal colonic mucosae. Mucosa immediately adjacent to cancer usually stained with AH-6 but not with KH-1, CC-1, or CC-2. Extended or trifucosyl LeY antigen expression was limited exclusively to premalignant (adenomatous) polyps and was invariably absent from nonpremalignant (hyperplastic) polyps. Moreover, among adenomatous polyps, extended LeY antigen expression tended to correlate with three parameters of malignant potential: larger polyp size; villous histology, and severe dysplasia. AH-6 failed to distinguish between hyperplastic and adenomatous polyps. In second-trimester fetal colonic mucosa, AH-6 bound to both proximal and distal segments whereas KH-1, CC-1, and CC-2 bound only to proximal segments. We conclude that in human colon, the LeY hapten is an oncodevelopmental cancer-associated antigen and extended LeY antigens are highly specific markers for malignancy and premalignancy.

This is a collective review of all cases of HOS reported from China. Of the 24 total cases, 18 are living and are included in this report. The clinical features, including previously undescribed associated anomalies, mode of transmission in the family, genetic characteristics, and dermatoglyphics of this familial upper limb-cardiovascular syndrome, are presented. A practical classification of the syndrome is proposed based on the relative preponderance of either upper limb deformities or cardiovascular anomalies.

Using HT-29 colonic cancer cell line as the immunogen, monoclonal antibody Hb3 was generated, which can react to colonic carcinoma and several colonic cancer cell lines. In this paper, formalin fixed tissue sections of the human colonic cancer and adenoma were tested by indirect immunofluorescence using monoclonal antibody Hb3. In 20 colonic cancers, 16 belonged to well and moderately differentiated carcinoma, 4 to poorly differentiated carcinoma and mucoid adenocarcinoma. All of the former reacted to monoclonal antibody Hb3 but no reaction was seen in the latter. The positive rate was 80%. By the same method, 20 colonic adenomas were also studied. 19 were negative except one, a papillo-adenoma with dysplasia, which was weakly positive. The results indicate that monoclonal antibody Hb3 can be used in differentiating colonic carcinoma from adenoma and as an effective indicator of the malignant change of colonic adenoma.

One member of a Chinese family with Holt-Oram syndrome also had high myopia, which is a hitherto unreported feature. The genetic background of this unusual association is discussed.