A gene for Hirschsprung disease maps to the proximal long arm of chromosome 10

Hirschsprung disease (HSCR) is a frequent congenital disorder (1 in 5,000 newborns) of unknown origin characterized by the absence of parasympathetic intrinsic ganglion cells of the hindgut. Taking advantage of a proximal deletion of chromosome 10q (del 10q11.2-q21.2) in a patient with total colonic aganglionosis, and of a high-density genetic map of microsatellite DNA markers, we performed genetic linkage analysis in 15 non-syndromic long-segment and short-segment HSCR families. Multipoint linkage analysis indicated that the most likely location for a HSCR locus is between loci D10S208 and D10S196, suggesting that a dominant gene for HSCR maps to 10q11.2, a region to which other neural crest defects have been mapped.

[Improvement of prostacyclin-thromboxane A2 balance in patients with acute myocardial infarction by intermittent aspirin]

Forty two patients with acute myocardial infarction (AMI) were randomly distributed to the following groups: (1) the non-aspirin-treated group; (2) the daily-aspirin-treated group (aspirin, 300mg, once everyday); (3) the intermittent-aspirin-treated group (aspirin, 300mg, once every three days). In addition to the three groups, a group of normal subjects was selected. Blood was taken by venipuncture of the antecubital vein in patients on the first, second, seventh, fourteenth and twenty-first hospitalized days. The plasma levels of 6-keto-prostaglandin F1 alpha(6-keto-PGF1 alpha) and thromboxane B2(TXB2) were measured respectively by the scintillation counting of radioimmunoassay. The ratio of 6-keto-PGF1 alpha to TXB2 (K/T ratio) was also calculated. Conclusions were as follows: (1) Intermittent treatment with low-dose aspirin is superior to daily treatment in improving the PGI2/TXA2 balance in patients with AMI. (2) Daily low-dose aspirin has cumulative inhibitory effects on PGI2 and TXA2 synthesis in AMI patients. While intermittent treatment has the same cumulative inhibitory effect on TXA2 synthesis as daily treatment, but no cumulative inhibitory effect on PGI2 synthesis.

GC/MS identification of tetramine in samples from human alimentary intoxication and evaluation of artificial carbonic kidneys for the treatment of the victims

One day in July 1991, 78 people became victims of accidental alimentary intoxication in a factory in Hebei Province, China. Related samples, including rodenticide bait, the artificial carbonic kidneys used for the treatment of the victims, and the victims' blood, were analyzed by GC/MS. Tetramine [80-12-6], a highly toxic rodenticide, was identified as the toxicant. The effectiveness of artificial carbonic kidneys was evaluated. The analytical results revealed that detoxification of the patients was effective 48 hours after intoxication by percolating their blood through artificial carbonic kidneys.

A model of stress relaxation in cross-bridge systems: effect of a series elastic element

Many experimental protocols employed in the study of muscle mechanics use tension transients as a probe of the magnitudes of the kinetic rates in the underlying cross-bridge dynamics. These transients could potentially be modified by the elastic elements that exist both within the fiber and at the points of attachment to the experimental apparatus. To better understand the magnitude of such modifications, we have used computer simulation to investigate the transients that would be expected for cross bridges acting on an actin filament attached to an elastic element. The original model of cross-bridge mechanics by A.F. Huxley was used (Prog. Biophys. 7: 255-318, 1957). After an isometric equilibrium is achieved, a tension transient is produced by changing the dissociation rate constant, g1, while holding the attachment rate constant, f1, fixed. This decreases the number of attached, force-producing cross bridges. We find that the tension transients are markedly slowed by the presence of even a few (> or = 2) nanometers of series elastic strain per half-sarcomere. Thus some rate constants inferred from mechanical transients (e.g., those induced by caged ligands) may underestimate the actual kinetic rates of the cross-bridge processes.

[Effects of "he xiang zhuang gongfu" on respiratory function in healthy adults]

Eleven healthy adults who practised He Xiang Zhuang Gongfu (HGF) were followed for 6 months; 15 pulmonary function tests were determined before HGF practice, 2 months and 6 months after HGF practice. All 11 subjects took the HGF exercise every day for 30 minutes. Samplings were taken before subjects had ever practised HGF as control value, immediately and 30 minutes after HGF exercise. In the 2nd month and 6th month of HGF practice. The results indicated that VO2 decreased after 2 and 6 months HGF practice, and the effect even persisted to 30 minutes after HGF exercise, indicating that HGF may reduce metabolic rate and decrease the oxygen consumption of body. The possible mechanism was discussed. MVV had an up tendency after HGF practice, which suggested the possibility of strengthening respiratory muscle by HGF. HGF may be a good physical exercise and can induce a wakeful hypometabolic physiologic state.

Defining topological equivalences in protein structures by means of a dynamic programming algorithm

An automatic algorithm for defining topological equivalences in protein structures is presented. The algorithm is based on a dynamic programming technique and self-consistent scoring method. We have used it to align pairs of similar protein structures of several protein families and to identify recurrent structural domains in aspartic proteinase 2APR. Its ability to find suboptimal paths permits a thorough comparison of proteins at each level in the hierarchy of the protein structure: secondary structure, super-secondary structure, domain and entire globular structure. The algorithm has been extended to the structure alignment of ribonucleic acid and can be extended to the structure alignment of any linear polymer.

A structure-activity relationship study of batracylin analogues

A number of isoindolo[1,2-b]quinazolines and some benzo[4,5]isoquinolino[1,2-b]quinazolines as structural modification analogues of the antitumor compound batracylin were synthesized and evaluated against HL-60 cell growth and in topoisomerase II-mediated DNA cleavage assays. Of the compounds studied, 10,12-dihydro-7,8-methylenedioxyisoindolo[1,2-b]quinazolin-1 2(10H)-one (1d), 2-amino-10,12-dihydroisoindolo[1,2-b]quinazolin-12(10H)-one (1p), and 2-amino-7,8-methylenedioxy-10,12-dihydroisoindolo[1,2-b] quinazolin-12(10H)-one (1ab) exhibited good inhibitory activities against HL-60 cell lines as well as induction of topo II-mediated DNA cleavage activities.

[Study on degradation of phenols in water]

The degradation of phenols in water and the effects of microbiolism, pH and dissolved oxygen (DO) on the degradation were investigated. The results showed that the degradation of phenols in water was mainly that of biochemistry, which depends on the existence of microbiolism. The most suitable pH for the degradation was 6 to 9, and no effects of DO on it were found. The accustomization of microbiolism with phenols would accelerate the degradation.

Immunological status of patients with obstructive jaundice and immunostimulatory effect of arginine

Sepsis is a major factor in the high mortality and morbidity following diagnostic and therapeutic procedures in patients with obstructive jaundice. The reasons for this increased susceptibility to infection are not fully understood. We therefore observed prospectively changes in immunological status of patients with obstructive jaundice in the perioperative period and studied immunological effects of perioperative arginine therapy. The results showed that there was a significant reduction in interleukin 2 (IL-2) production, interleukin 2 receptor (IL-2R) expression and lymphocyte response to phytohemagglutinin (PHA) mitogen in patients with obstructive jaundice compared with normal controls. After operation, the immune suppression in patients with obstructive jaundice was more significant. Arginine is a known T lymphocyte stimulator. Perioperative supplement with arginine significantly enhanced the immune function of patients with obstructive jaundice, the mechanism being related to increased IL-2 production and IL-2R expression.

Juxtaposition between activation and basic domains of human immunodeficiency virus type 1 Tat is required for optimal interactions between Tat and TAR

trans activation of the human immunodeficiency virus type 1 long terminal repeat requires that the viral trans activator Tat interact with the trans-acting responsive region (TAR) RNA. Although the N-terminal 47 amino acids represent an independent activation domain that functions via heterologous nucleic acid-binding proteins, sequences of Tat that are required for interactions between Tat and TAR in cells have not been defined. Although in vitro binding studies suggested that the nine basic amino acids from positions 48 to 57 in Tat bind efficiently to the 5' bulge in the TAR RNA stem-loop, by creating several mutants of Tat and new hybrid proteins between Tat and the coat protein of bacteriophage R17, we determined that this arginine-rich domain is not sufficient for interactions between Tat and TAR in vivo. Rather, the activation domain is also required and must be juxtaposed to the basic domain. Thus, in vitro TAR RNA binding does not translate to function in vivo, which suggests that other proteins are important for specific and productive interactions between Tat and TAR.

[A comparative study on the nasolance and graph pattern of cleft palate patients before and after operation]

The aim of the present study is to compare the nasolance score and graphic pattern of the nasometric registration before and after cleft palate repair. Sixty cleft palate patients were studied with nasometer. One month after operation the nasolance is significantly lower as compared with the preoperation sequence and the number of "up and down" pattern has increased significantly. These results indicate that the velopharygeal function starts to recover one month after operation and the speech training can be given at the mean time. The speech results should be assessed at least three months after operation.

Isolation, crystallization and preliminary diffraction analyses of human pancreatic alpha-amylase

Human pancreatic alpha-amylase has been isolated using a glycogen affinity precipitation procedure and crystallized in a form suitable for high resolution three-dimensional X-ray crystallographic analyses. Crystals are of the orthorhombic space group P2(1)2(1)2(1), with unit cell dimensions of a = 53.04 A, b = 74.80 A and c = 137.34 A, and contain only one protein molecule per asymmetric unit. Diffraction data have been collected and found to extend to 1.6 A resolution. These studies form the basis for elucidating the full atomic structure of human pancreatic alpha-amylase and thereby providing insight into the catalytic mechanism of this enzyme.

Demonstration of presynaptic protein kinase C activation following long-term potentiation in rat hippocampal slices

Pharmacological and biochemical evidence implicate the Ca2+ and phospholipid-dependent protein kinase C in long-term potentiation. The in vitro hippocampal slice preparation was used to demonstrate redistribution of protein kinase C from cytosol to membrane and protein kinase C-dependent phosphorylation of the presynaptic growth-associated protein-43 substrate following long-term potentiation induction in area CA1. Protein kinase C translocation was assessed using both quantitative immunoblotting with a monoclonal antibody recognizing a common epitope in the alpha and beta isoforms of protein kinase C and Ca2+ and phospholipid-dependent phosphorylation of exogenous histone substrate. Slices examined 5 min after tetanus-induced spike potentiation showed no change in protein kinase C redistribution, whereas slices examined at 15-, 30- and 60-min intervals all showed a similar degree of protein kinase C translocation to membrane, although only at 15 min was the effect statistically significant. Additionally, an increase in protein kinase C-dependent growth-associated protein 43 phosphorylation was observed 10 min after high-frequency stimulation. The translocation of protein kinase C and phosphorylation of growth-associated protein 43 were dependent upon high-frequency (repetitive 400 Hz) afferent stimulation, as no effects were observed in slices receiving low-frequency (1 Hz) or no stimulation. The N-methyl-D-aspartate receptor antagonist, DL-2-amino-5-phosphonovaleric acid (50 microM), inhibited induction of long-term potentiation, redistribution of protein kinase C and phosphorylation of growth-associated protein 43. A significant redistribution of the predominantly presynaptic protein kinase C isoform, protein kinase C-alpha, was also detected 15 min after induction of long-term potentiation using an alpha-isoform-specific monoclonal antibody. These observations support a presynaptic role for protein kinase C and growth-associated protein 43 in the early maintenance phase of LTP, and further suggest that a retrograde messenger produced postsynaptically following N-methyl-D-aspartate receptor activation mediates these effects.

Serologic analysis of a murine chemokine, TCA3

The TCA3 gene encodes a proinflammatory cytokine related to IL-8 and MCP-1 (JE). TCA3 mRNA is produced by T cells in response to stimulation with Ag or Con A. Glycosylated and nonglycosylated forms of rTCA3 produced by transfected Chinese hamster ovary cells were purified. rTCA3 was used to immunize hamsters and produce mAb. Four mAb were characterized; each was specific for TCA3, failing to react with the closely related molecule MCP-1 (JE). Western blotting also demonstrated that all four mAb specifically recognize rTCA3, native TCA3 produced by activated mouse T cells, and the nonglycosylated TCA3 core protein. A sensitive and specific capture ELISA for TCA3 quantitation was developed, allowing measurement of TCA3 levels in the supernatants from activated murine splenocytes and T cell clones. In addition, two mAb demonstrated dose-dependent neutralization of TCA3 inflammatory activity. Thus, the results directly demonstrate that TCA3 is expressed in an activation-specific manner by mouse T cells. The data also provide characterization of mAb reagents specific for this new cytokine.

Serologic analysis of a murine chemokine, TCA3

The TCA3 gene encodes a proinflammatory cytokine related to IL-8 and MCP-1 (JE). TCA3 mRNA is produced by T cells in response to stimulation with Ag or Con A. Glycosylated and nonglycosylated forms of rTCA3 produced by transfected Chinese hamster ovary cells were purified. rTCA3 was used to immunize hamsters and produce mAb. Four mAb were characterized; each was specific for TCA3, failing to react with the closely related molecule MCP-1 (JE). Western blotting also demonstrated that all four mAb specifically recognize rTCA3, native TCA3 produced by activated mouse T cells, and the nonglycosylated TCA3 core protein. A sensitive and specific capture ELISA for TCA3 quantitation was developed, allowing measurement of TCA3 levels in the supernatants from activated murine splenocytes and T cell clones. In addition, two mAb demonstrated dose-dependent neutralization of TCA3 inflammatory activity. Thus, the results directly demonstrate that TCA3 is expressed in an activation-specific manner by mouse T cells. The data also provide characterization of mAb reagents specific for this new cytokine.

Synthesis and Properties of 6A-Amino-6A-deoxy-α and β-cyclodextrin

The monotosylates obtained by treatment of α- and β- cyclodextrin with p- methylbenzenesulfonyl chloride reacted with ammonia to give the title compounds. These amines are of unusually low basicity , with pKa values of 8.70 and 8.72, respectively. In water at 25°, the hydrochloride salt of the amine derived from β- cyclodextrin is approximately 40 times more soluble than β-cyclodextrin and, through complexation, the salt increases the solubility of Nabumetone over 800 times.

A microsatellite genetic linkage map of human chromosome 18

We isolated nine new microsatellite markers from chromosome 18 and further characterized and mapped eight microsatellites developed in other laboratories. We have constructed a framework linkage map of chromosome 18 that includes 14 microsatellite markers (12 dinucleotide and 2 tetranucleotide) and 2 RFLP markers. Cytogenetic localization for the microsatellites was performed by PCR amplification of 18 somatic cell hybrids containing different deletions of chromosome 18. Twelve of the microsatellites and one of the RFLPs have heterozygosites greater than 70%. The average heterozygosity of the markers included in the map is 72%. In addition, we have made provisional placements of 3 more microsatellite markers and 2 more RFLP markers. The map lengths (in Kosambi centimorgans) are as follows: sex-averaged, 109.3 cM; male, 72.4 cM; female, 161.2 cM. The average distance between markers in the sex-averaged map is 7.3 cM, and the largest gap between markers is 16.7 cM. Analysis of the data for differences in the female:male map distance ratio revealed significant evidence for a constant difference in the ratio (chi 2 = 32.25; df = 1; P < 0.001; ratio = 2.5:1). Furthermore, there was significant evidence in favor of a variable female:male map distance ratio across the chromosome compared to a constant distance ratio (chi 2 = 27.78; df = 14; P = 0.015). To facilitate their use in genomic screening for disease genes, all of the microsatellite markers used here can be amplified under standard PCR conditions, and most can be used in duplex PCR reactions.

Three new monoclonal antibodies that define a unique antigen associated with prolymphocytic leukemia/non-Hodgkin's lymphoma and are effectively internalized after binding to the cell surface antigen

Prolymphocytic leukemia (PLL) is closely related to chronic lymphocytic leukemia (CLL), but present with distinctive clinical/laboratory features and associated with much worse prognosis. In this study, we generated three new IgG1-kappa monoclonal antibodies (MoAbs), termed SN8, SN8a and SN8b, by use of an unconventional approach, ie, by using an isolated B PLL antigen preparation to immunize mice. These MoAbs, particularly SN8, showed a highly selective reactivity to B PLL and B non-Hodgkin's lymphoma (NHL) among various human leukemia-lymphoma specimens tested; eg, SN8 was capable of effectively distinguishing B PLL from B CLL as well as from hairy cell leukemia (HCL) cell specimens. The cell surface antigen defined by the three MoAbs was determined to be a covalently linked heterodimeric glycoprotein complex (gp49/40) consisting of a 49,000 dalton (alpha-chain) and a 40,000-dalton component (beta-chain). Epitope comparison showed that the epitope defined by SN8 (SN8 epitope) is in close proximity to SN8a epitope but in a distant position from SN8b epitope. Western blot analysis showed that both SN8 and SN8a epitopes are on the beta-chain, but SN8b epitope was not detected on either the alpha- or the beta-chain of the reduced antigen in the same analysis. Binding of either SN8 or SN8b to the cell surface gp49/40 did not cause significant downregulation of the antigen expression whereas binding of SN8a to the antigen caused small (approximately 20%) decrease in the antigen expression. Among the various normal peripheral blood cells, only a subpopulation (6.0% to 24.2% among different specimens derived from different donors) of B cells reacted with the SN8 series MoAbs; these MoAbs showed no significant reactivity against T cells, granulocytes, monocytes, erythrocytes, and platelets. Minimal or no significant reactivity (0 to 2.6% among different specimens) was detected against normal bone marrow cells. Ricin A-chain conjugates of the three MoAbs are all strongly effective for specific killing of SN8 antigen-expressing leukemia cells in the absence of any potentiators; furthermore, the addition of 10 mmol/L NH4Cl, a potentiator, enhanced strongly the cytotoxic activities of the SN8, SN8a, and SN8b conjugates. Thus, each of the three MoAbs was effectively internalized after binding to the cell surface antigen.

A novel B cell-derived coactivator potentiates the activation of immunoglobulin promoters by octamer-binding transcription factors

A novel B cell-restricted activity, required for high levels of octamer/Oct-dependent transcription from an immunoglobulin heavy chain (IgH) promoter, was detected in an in vitro system consisting of HeLa cell-derived extracts complemented with fractionated B cell nuclear proteins. The factor responsible for this activity was designated Oct coactivator from B cells (OCA-B). OCA-B stimulates the transcription from an IgH promoter in conjunction with either Oct-1 or Oct-2 but shows no significant effect on the octamer/Oct-dependent transcription of the ubiquitously expressed histone H2B promoter and the transcription of USF- and Sp1-regulated promoters. Taken together, our results suggest that OCA-B is a tissue-, promoter-, and factor-specific coactivator and that OCA-B may be a major determinant for B cell-specific activation of immunoglobulin promoters. In light of the evidence showing physical and functional interactions between Oct factors and OCA-B, we propose a mechanism of action for OCA-B and discuss the implications of OCA-B for the transcriptional regulation of other tissue-specific promoters.

[Synchronized control of specific gravity, drug contents and recovery rate of inspissated extracts]

As a result of experimentation we have developed a method that helps to synchronize the control of the three preset criteria, i.e. specific gravity, drug contents and recovery rate, in the process of preparing traditional Chinese medicines. Simple and easy to use, the method is also good for similar purposes in the preparation of traditional Chinese syrups.