[Seed rain and seed bank of constructive species in evergreen broadleaved forest at Chongqing Simian Mountain]

The study shows that the early and late seed rains of constructive tree species in evergreen broadleaved forest at Chongqing Simian Mountain had no activity. The bigger the seeds of the species and the earlier or later the seeds of the species matured, the higher the proportion of the seed rain damaged by animals. The quantitative variation of seed rain, active seed rain and seed bank did not take place at the same time. At early time, the number of seed banks of Castanopsis fargesii, Lithocarpus glabra, Quercus myrsinrefolia, Castanopsis plasyacantha, Cinamomum subavenium which own more active seed rain increased by geomitric series. The seed banks of Castanopsis orthacantha and Schima argentea were small, only survived a short time, and did not sprout next year. The quantitative dynamics of seed banks and their increasing or decreasing rates were decided by the proportion damaged by animals, dying speed of seeds and their resistance to pathogens and adverse circumstances, and the state of seed germination.

[The role of nitric oxide in the pathogenesis of portal hypertension]

OBJECTIVE

To investigate the role of nitric oxide in the pathogenesis of portal hypertension.

METHODS

We measured the portal venous pressure of 75 patients via a catheter and detected the levels of plasma endotoxin and NO(2)(-)/NO(3)(-).

RESULTS

The mean levels of plasma endotoxin and NO(2)(-)/NO(3)(-) (0.249 +/- 0.112 Eu/ml and 55.9 +/- 26.2 micromol/L) in portal hypertensive patients were significantly higher than those in the controls, and the highest values were observed in the portal venous blood. The mean portal venous pressure of the portal hypertensive patients was 35.5 +/- 4.4 cm H(2)O and was positively correlated with the levels of NO(2)(-)/NO(3)(-) (n = 25, r = 0.55, P < 0.01). Positive correlation existed between them during the postoperative period (r = 0.57, P < 0.05). There was a negative correlation between the levels of albumin and NO(2)(-)/NO(3)(-) (n = 75, r = -0.35, P < 0.01), and the mean levels of NO(2)(-)/NO(3)(-) were 72.4 +/- 20.3 micromol/L in the patients with ascites, much higher than those (50.3 +/- 21.0 micromol/L) without ascites.

CONCLUSIONS

The levels of plasma endotoxin and nitric oxide were elevated in patients with portal hypertension, and NO might play an important role in the abnormal elevation of portal venous pressure and the damage to liver function.

Molecular cloning of canine bullous pemphigoid antigen 2 cDNA and immunomapping of NC16A domain by canine bullous pemphigoid autoantibodies

The autoantibody-mediated subepidermal blistering skin disease bullous pemphigoid affects both humans and dogs. We previously demonstrated that canine bullous pemphigoid patient's autoantibodies targeted skin basement membrane component and a 180-kDa keratinocyte protein. We extend our works to partially isolate the cDNA encoding canine bullous pemphigoid antigen 2 (BPAg2, BP180). Total RNA extracted from a papillomavirus-immortalized canine keratinocyte cell line and a cultured canine squamous carcinoma cell line SCC 2/88 were used to isolate fragments of cDNA encoding BPAg2 by reverse transcription-PCR and 5'-rapid amplification of cDNA end. The isolated sequence included the 5'-untranslated region, the entire intracellular, transmembranous, and extracellular NC16A autoantigenic domains, plus a small segment of the collagenous domain. Sequence analyses of the isolated cDNA showed 87 and 85% identities between canine and human at the nucleotide sequence and at the deduced amino acid sequence levels, respectively. The canine BPAg2 sequence was confirmed by a rabbit antibody raised against a 18-amino acid peptide deduced from the canine NC16A nucleotide sequence. Autoantibodies from canine bullous pemphigoid patients' sera recognized epitopes within the human NC16A domain. The cloning of the cDNA encoding this disease-associated protein may allow us to develop a canine model in dissecting the immunopathologic mechanism underlying bullous pemphigoid.

The mutation of insulin receptor substrate-1 gene in Chinese patients with non-insulin-dependent diabetes mellitus

OBJECTIVE

To identify the relationship between mutation in the insulin receptor substrate-1 (IRS-1) gene and the incidence of non-insulin-dependent diabetes mellitus (NIDDM) in the Chinese population.

METHODS

Samples were obtained from 68 Chinese patients with NIDDM and 68 control subjects. The +1700-(+)4437 bp fragment of the IRS-1 gene was screened by polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis. All SSCP variations were submitted to DNA sequence analysis.

RESULTS

Two amino acid variations [GGG-->AGG (G971 R) and CCT-->TCT (P1079 S)] and 3 silent mutations [GAT-->GAC(D422D), CCA-->CCC(P737 P) and GCA-->GCG (A804 A)] were identified, among which the CCA-->CCC(P737 P) and CCT-->TCT(P1079S) have not been previously reported. All five variations were found in Chinese patients with NIDDM, while GCA-->GCG(A804A) was the only one found in control subjects. The overall incidence of the five variations in Chinese patients with NIDDM were much higher than that in control subjects (38.2% vs 7.4%, chi 2 = 18.42, P < 0.01). The most common polymorphism in the Chinese population was GCA-->GCG (A804A), and its frequency was significantly higher in Chinese patients with NIDDM than in controls (26.5% vs 7.4%, chi 2 = 8.84, P < 0.01). The homozygotes of the variation in patients with NIDDM and control subjects were 8.8% and 1.5%, respectively (chi 2 = 2.41, P > 0.05).

CONCLUSION

These results indicate that there may be a relation between these nucleotide variations of IRS-1 gene and Chinese patients with NIDDM.

[Study on lipids and other volatile constituents in Pheretima aspergillum]

To study chemical constituents in Pheretima aspergillum, three kinds of fractions were obtained from this drug by soxhlet extraction with different solvents, and the chemical structures of thirty-six volatile components were identified by means of GC-MS. The eleven in ether fraction were all lipids and the relative content of non-saturated fatty acid was the highest(27.70%) such as oleic acid, linoleic acid, arachidonic acid and eicosatrienoic acid; There were eight lipids in acetone fraction (35.75%), which included one kind of nonsaturated fatty acid (linoleic acid); There were thirteen lipids in ethanol fraction (72.09%), which non-saturated fatty acid has never been detected. This study has determined the lipid composition in Pheretima aspergillum, especially non-saturated fatty acid, and afforded chemical base to cardio-cerebro-vascular therapy.

Expression cloning of protein targets for 3-phosphorylated phosphoinositides

The phosphatidylinositol 3-kinase (PI 3'-K) family of lipid kinases play a critical role in cell proliferation, survival, vesicle trafficking, motility, cytoskeletal rearrangements, and oncogenesis. To identify downstream effectors of PI 3'-K, we developed a novel screen to isolate proteins that bind to the major products of PI 3'-K: phosphatidylinositol-3,4-bisphosphate (PtdIns-3,4-P(2)) and PtdIns-3,4,5-trisphosphate (PtdIns-3,4,5-P(3)). This screen uses synthetic biotinylated analogs of these lipids in conjunction with libraries of radiolabeled proteins that are produced by coupled in vitro transcription/translation reactions. The feasibility of the screen was initially demonstrated using avidin-coated beads prebound to biotinylated PtdIns-3,4-P(2) and PtdIns-3,4,5-P(3) to specifically isolate the pleckstrin homology domain of the serine/threonine kinase Akt. We then demonstrated the utility of this technique in isolating novel 3'-phosphorylated phosphatidylinositol (3'-PPI)-binding proteins through the preliminary screening of in vitro transcribed/translated cDNAs from a small pool expression library derived from mouse spleen. Three proteins were isolated that bound specifically to 3'PPIs. Two of these proteins have been previously characterized as PIP3BP/p42(IP4) and the PtdIns-3,4,5-P(3)-dependent serine/threonine kinase phosphoinositide-dependent kinase 1. The third protein is a novel protein that contains only a Src homology 2 domain and a pleckstrin homology domain; this protein has a higher specificity for both PtdIns-3,4,5-P(3) and PtdIns-3,4-P(2) than for PtdIns-4, 5-bisphosphate. Transcripts of this novel gene are present in every tissue analyzed but are most prominently expressed in spleen. We have renamed this new protein PHISH for 3'-phosphoinositide-interacting Src homology-containing protein. This report demonstrates the utility of this technique for isolating and characterizing 3'-PPI-binding proteins and has broad applicability for the isolation of binding domains for other lipid products.

Improved techniques for kidney transplantation in the monkey

Improved microsurgical techniques for kidney transplantation in the monkey are described. The left graft kidney is transplanted to the lower part of abdomen with end-to-side anastomoses of renal artery to aorta without a patch of aorta, renal vein to inferior vena cava, and end-to-end anastomosis of donor and recipient ureter with 8-0 nylon sutures in a bilateral nephrectomized recipient monkey. We recently performed 60 kidney transplantations in Vervet monkeys. None died of surgery or surgical complications. This reproducible model provides a useful tool to test new immunosuppressants and to investigate the mechanism of drug-induced tolerance and xenotransplantation in primates as a support to clinical trial.

Synergistic effect of rapamycin and cyclosporine in prevention of acute kidney allograft rejection in the mouse

The effect of rapamycin (RAPA) and cyclosporine A (CsA) monotherapy and combination therapy was examined in prevention of kidney allograft rejection in the mouse. Both drugs were administered orally for up to 14 days in BALB/c (H-2(d)) to C57BL/6 (H-2(b)) mice strong combination. Six groups were treated with RAPA and/or CsA. This study shows that concomitant therapy of RAPA and CsA produces strong synergistic interaction in prolonging renal allograft survival in mice when compared with monotherapy of RAPA or CsA.

Prolongation of rat heart allograft survival with K(+)ATP-dependent channel modulators

Controversies exist regarding the immunoregulatory properties of K(+) ATP channel modulators. We investigated the effects of aprikalim, a K(+) ATP-dependent channels activator, and glibenclamide and gliclazide, two inhibitors of K(+) ATP-dependent channels, on the prolongation of heart allograft survival in the rat. Nine groups (n >/= 5) were involved in this study with the Brown-Norway to Lewis rat combination treated with aprikalim, glibenclamide, gliclazide, and/or cyclosporine. The results indicate that modulators of K(+) ATP-dependent channels can improve the survival of rat heart allograft without interfering with the immunosuppressive properties of cyclosporine.

Cyclin K functions as a CDK9 regulatory subunit and participates in RNA polymerase II transcription

Important progress in the understanding of elongation control by RNA polymerase II (RNAPII) has come from the recent identification of the positive transcription elongation factor b (P-TEFb) and the demonstration that this factor is a protein kinase that phosphorylates the carboxyl-terminal domain (CTD) of the RNAPII largest subunit. The P-TEFb complex isolated from mammalian cells contains a catalytic subunit (CDK9), a cyclin subunit (cyclin T1 or cyclin T2), and additional, yet unidentified, polypeptides of unknown function. To identify additional factors involved in P-TEFb function we performed a yeast two-hybrid screen using CDK9 as bait and found that cyclin K interacts with CDK9 in vivo. Biochemical analyses indicate that cyclin K functions as a regulatory subunit of CDK9. The CDK9-cyclin K complex phosphorylated the CTD of RNAPII and functionally substituted for P-TEFb comprised of CDK9 and cyclin T in in vitro transcription reactions.

[The treatment of stricture of larynx and trachea with Ni-Ti shape memory alloy stand]

OBJECTIVE

To evaluate the use of Ni-Ti shape memory alloy stand in the treatment of stricture of larynx and trachea.

METHODS

The clinical materials of 14 patients were analyzed. All patients had stricture of larynx and trachea and accepted the treatment with Ni-Ti shape memory alloy stand.

RESULTS

All patients breathed freely after the operation, and the trachea fistula was closed at the time of operation. The follow-up survey for these patients lasted for 2 to 12 months. None of the patients had signs of the stricture of the respiratory tract. The short-term effective rate was 100%.

CONCLUSION

Ni-Ti shape memory alloy stand can expand the stricture of larynx and trachea quickly and thus improve the breath effectively. It can be used as a routine method in the treatment of stricture of larynx and trachea.

Design and synthesis of novel alpha(1)(a) adrenoceptor-selective antagonists. 4. Structure-activity relationship in the dihydropyrimidine series

We have previously disclosed dihydropyridines such as 1a,b as selective alpha(1a) antagonists as a potential treatment for benign prostatic hyperplasia (BPH). The propensity of dihydropyridines toward an oxidation led us to find suitable replacements of the core unit. The accompanying papers describe the structure-activity relationship (SAR) of dihydropyrimidinones 2a,b as selective alpha(1a) antagonists. We report herein the SAR of dihydropyrimidines such as 4 and highlight the similarities and differences between the dihydropyrimidine and dihydropyrimidinone series of compounds.

The Ig fold of the core binding factor alpha Runt domain is a member of a family of structurally and functionally related Ig-fold DNA-binding domains

BACKGROUND

CBFA is the DNA-binding subunit of the transcription factor complex called core binding factor, or CBF. Knockout of the Cbfa2 gene in mice leads to embryonic lethality and a profound block in hematopoietic development. Chromosomal disruptions of the human CBFA gene are associated with a large percentage of human leukemias.

RESULTS

Utilizing nuclear magnetic resonance spectroscopy we have determined the three-dimensional fold of the CBFA Runt domain in its DNA-bound state, showing that it is an s-type immunoglobulin (Ig) fold. DNA binding by the Runt domain is shown to be mediated by loop regions located at both ends of the Runt domain Ig fold. A putative site for CBFB binding has been identified; the spatial location of this site provides a rationale for the ability of CBFB to modulate the affinity of the Runt domain for DNA.

CONCLUSIONS

Structural comparisons demonstrate that the s-type Ig fold found in the Runt domain is conserved in the Ig folds found in the DNA-binding domains of NF-kappaB, NFAT, p53, STAT-1, and the T-domain. Thus, these proteins form a family of structurally and functionally related DNA-binding domains. Unlike the other members of this family, the Runt domain utilizes loops at both ends of the Ig fold for DNA recognition.

[The genotype-based haplotype relative risk and transmission disequilibrium test analyses of familial febrile convulsions]

OBJECTIVE

To confirm the linkage of familial febrile convulsions to the short arm of chromosome 6(6p) or the long arm of chromosome 8(8q).

METHODS

The authors finished genotyping of Pst I locus on the coding region of heat shock protein (HSP) 70, 5'untranslated region of HSP70-1, 3' untranslated region of HSP70-2, D8S84 and D8S85. The data were processed by the genotype-based haplotype relative risk(GHRR) and transmission disequilibrium test(TDT) methods in PPAP.

RESULTS

Some signs of association and disequilibrium between D8S85 and FC were shown by GHRR and TDT.

CONCLUSION

A suspect linkage of familial febrile convulsions to the long arm of chromosome 8 has been proposed.

[The treatment to esophagus stricture with Ni-Ti shape memory alloy stand(with the report of 19 clinical cases)]

OBJECTIVE

To discuss the use of Ni-Ti shape memory alloy stand in treating the stricture of esophagus.

METHOD

After finding the stricture part of esophagus under X-ray, the metal guide string was put through the esophagoscope. Dilatation of esophagus was performed firstly. Then the inserting instrument, which has the Ni-Ti shape memory alloy stand inside, was put through the stricture part along the metal guide string and the stand which can return to its original shape automatically was released. Barium meal examination of esophagus was performed after the operation to determine the site of the stand and to realize the smooth degree of esophagus.

RESULT

All 19 patients got a successful operation at one time. They swallowed freely after the operation. The effective rate was 100%.

CONCLUSION

Ni-Ti shape memory alloy stand can dilate the stricture of esophagus quickly, improve swallowing function obviously. The operation can be easily performed. The therapeutic effectiveness is reliable, and there is no serious complication. This can be used as a routine method in treating the stricture of esophagus.

[Limited pleuro-pneumonectomy for bronchogenic carcinoma associated with cancerous pleural effusion]

OBJECTIVE

To evaluate the effects of limited pleuro-pneumonectomy for bronchogenic carcinoma associated with cancerous pleural effusion.

METHODS

From January. 1994 to December 1997 we performed limited pulmonary lobectomy wedge resection of lung, resection of the metastases of the parietal pleura, visceral pleura, diaphragmatic pleura and pericardiac pleura, and electro incision of the micormetastases of the above position as well as cleaning the mediastinal lymph nodes in 14 cases.

RESULTS

The 14 cases were followed-up to December 1998. Eight patients of them died, the other 6 patients survived with a survival period of 7 - 30 months (median survival period 16.5 months). No pleural effusions recurrence was seen. The longest survival period was 30 months. There were no operative mortality and no severe postoperative complication. Chest distress, dyspnea and pain of chest or abdomen were relieved.

CONCLUSIONS

This simple method has such advantages as, less traumatic, rapid rehabilitation and effective control of pleural effusion. The postoperative survival period is longer than that of palliative operation and medical therapy. The pain caused by parietal pleural metastasis can be relieved.

[Evaluation of mass screening for breast cancer in the Somme district (France) between 1990 and 1996]

BACKGROUND

Randomized clinical trials have demonstrated that screening by mammography can reduce breast cancer mortality by 30% in women aged 50 to 69 years. In France, pilot screening programs were begun in 1989 and particularly in the Somme district. After 6 years and two rounds, the aim of this study was to assess the quality and the effectiveness of this screening program.

METHODS

The quality of the campaign was measured concerning effectiveness (recall rate, positive predictive value of screening test or of the screening procedure, intervention rate, breast cancer detection rate) or quality (percentage of in situ cancers, invasive cancers smaller than 10 mm, invasive cancers without lymph node invasion). These indicators were compared with European targets.

RESULTS

Attendance rates at 6 years ranged from 33.6% to 37.1%. The recall rate was 14.3% in the first and 7.8% in the second round, 6.4 and 6 cancers were detected per 1,000 women screened during the first and second round, and 38.5% of invasive cancers were of 10 mm or less (27.4% during the first round) and 70.8% had no nodal involvement (68.3% during the first round).

CONCLUSION

Results from the screening system are variable yet satisfactory overall, due to the progressive implementation of quality assurance. However attendance rates remain low, whereas actual coverage is 64% in Somme district.

Are lignins optically active?

The accepted derivation of lignins from non(enzymatically)-controlled radical coupling reactions has been recently challenged, and it is relevant to ascertain unequivocally whether lignins are or are not (as normally assumed) optically active. Two approaches were used. First, DFRC (derivatization followed by reductive cleavage) dimers derived from beta-5- and beta-beta-units in pine lignins, which certainly retain unaltered chiral centers (as well as beta-1- and beta-O-4-units where the intactness may be debated), were shown to be optically inactive by circular dichroism (CD) and chiral high-performance liquid chromatography. CD of beta-5-derived dimers following enantiomeric separation readily demonstrated the sensitivity of the method. Second, no optical activity could be detected (above 250 nm to avoid carbohydrate contributions) by CD of lignin isolates from pine, kenaf, maize, or a CAD-deficient pine mutant. Representative lignins are therefore not, within limits of detection by these methods, optically active.

Arylpropane-1,3-diols in lignins from normal and CAD-deficient pines

Significant quantities of arylopropane-1,3-diols have been identified in lignins isolated from a CAD-deficient pine mutant; smaller amounts are also present in lignins from normal pine. They arise from dihydroconiferyl alcohol via the action of peroxidases which are responsible for the radical generation steps of lignification. The structures in the complex lignin polymers are proven using 2D and 3D NMR of isolated lignin fractions.

'Green revolution' genes encode mutant gibberellin response modulators

World wheat grain yields increased substantially in the 1960s and 1970s because farmers rapidly adopted the new varieties and cultivation methods of the so-called 'green revolution'. The new varieties are shorter, increase grain yield at the expense of straw biomass, and are more resistant to damage by wind and rain. These wheats are short because they respond abnormally to the plant growth hormone gibberellin. This reduced response to gibberellin is conferred by mutant dwarfing alleles at one of two Reduced height-1 (Rht-B1 and Rht-D1) loci. Here we show that Rht-B1/Rht-D1 and maize dwarf-8 (d8) are orthologues of the Arabidopsis Gibberellin Insensitive (GAI) gene. These genes encode proteins that resemble nuclear transcription factors and contain an SH2-like domain, indicating that phosphotyrosine may participate in gibberellin signalling. Six different orthologous dwarfing mutant alleles encode proteins that are altered in a conserved amino-terminal gibberellin signalling domain. Transgenic rice plants containing a mutant GAI allele give reduced responses to gibberellin and are dwarfed, indicating that mutant GAI orthologues could be used to increase yield in a wide range of crop species.

Techniques for covering soft tissue defects resulting from plantar ulcers in leprosy: Part I--General considerations and summary of results

Recurrent plantar ulceration is a common and serious complication occurring consequent to impairment of the tibial nerve in leprosy patients. In spite of many therapies and long therapeutic course, it is extremely difficult to abolish this complication in many cases because of extensive skin and soft tissue cushion loss due to repeated infection. Since the early 70's we have been using microscopic surgical techniques to reconstruct the ulcerated area using eight types of the flaps. In this series of papers we review our experience (76 patients). Post-operatively, the flaps survived in all cases, the long-term results have proved satisfactory, and recurrent ulceration occurred in only three patients.

Increased hemangioblast commitment, not vascular disorganization, is the primary defect in flt-1 knock-out mice

We previously demonstrated the essential role of the flt-1 gene in regulating the development of the cardiovascular system. While the inactivation of the flt-1 gene leads to a very severe disorganization of the vascular system, the primary defect at the cellular level was unknown. Here we report a surprising finding that it is an increase in the number of endothelial progenitors that leads to the vascular disorganization in flt-1(−/−) mice. At the early primitive streak stage (prior to the formation of blood islands), hemangioblasts are formed much more abundantly in flt-1(−/−) embryos. This increase is primarily due to an alteration in cell fate determination among mesenchymal cells, rather than to increased proliferation, migration or reduced apoptosis of flt-1(−/−) hemangioblasts. We further show that the increased population density of hemangioblasts is responsible for the observed vascular disorganization, based on the following observations: (1) both flt-1(−/−) and flt-1(+/+) endothelial cells formed normal vascular channels in chimaeric embryos; (2) wild-type endothelial cells formed abnormal vascular channels when their population density was significantly increased; and (3) in the absence of wild-type endothelial cells, flt-1(−/−) endothelial cells alone could form normal vascular channels when sufficiently diluted in a developing embryo. These results define the primary defect in flt-1(−/−) embryos at the cellular level and demonstrate the importance of population density of progenitor cells in pattern formation.