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91.
The benzimidazole derivative Hoechst 33258 was added at various concentrations to human leukocyte cultures. After 16 or 24 h of treatment, with concentrations equal to or greater than 100 mug/ml of Hoechst 33258, a number of chromosomes showed regions in which the chromatin was undercontracted. The centromeric regions of chromosome 1 and, more rarely, of chromosomes 3 and 9 appeared to be decondensed. Short decondensed regions were also present on the long arms of chromosomes 1 and 2. The possible nature of these regions is discussed.  相似文献   
92.
93.
The synthesis of the amino-protected decapeptide tert-butyloxycarbonylhydrazide corresponding to positions 15-24 of the amino acid sequence of porcine pancreatic secretory trypsin inhibitor II (Kazal inhibitor) is described. The tripeptide free base threonyl-beta-tert-butylaspartylglycine tert-butyloxycarbonylhydrazide (sequence 22-24) was acylated with 1-succinimidyl o-nitrophenylsulfenylvalyl-S-acetamidomethylcysteinylglycinate (sequence 19-21). Removal of the amino protecting group from the resulting hexapeptide followed by acylation of the free base with either benzyloxycarbonylisoleucyl-O-tert-butyltyrosylasparaginylproline or O-nitrophenylsulfenylisoleucyl-O-tert-butyltyrosylasparaginylproline, via the pyrazoline active ester method, yielded the decapeptide tert-butyloxycarbonylhydrazide (sequence 15-24) in the form of Nalpha-benzyloxycarbonyl or Nalpha-O-nitrophenylsulfenyl derivative. The stereochemical homogeneity of the two decapeptides was assessed, after partial deprotection with liquid hydrogen fluoride, or thioacetamide and aqueous 90% trifluoroacetic acid, by digestion with papain and aminopeptidase M followed by quantitative amino acid analysis.  相似文献   
94.
Synthesis is described of the protected tetrapeptide corresponding to positions 11-14 of the primary structure of the porcine pancreatic secretory trypsin inhibitor II (Kazal), in the form of free acid as well as protected hydrazide. The tetrapeptide tert-butyloxycarbonylglycyl-S-acetamidomethylcysteinylprolyl-Nepsilon-trifluoroacetyl-lysine was prepared by stepwise elongation from the C-terminal Nepsilon-trifluoroacetyllysine using successively 1-succinimidyl benzyloxycarbonylprolinate, p-nitrophenyl N-tert-butyloxycarbonyl-S-acetamidomethylcysteinate and 1-phenyl-3-methyl-4-(tert-butyloxycarbonylglycyl)-oximinyl-5-(benzyloxycarbonylglycyl)-imino-2-pyrazoline as acylating agents. Alternately, the dipeptide benzyloxycarbonylprolyl-Nepsilon-trifluoroacetyllsine was transformed into the corresponding tert-butyloxycarbonylhydrazide which was reacted, after catalytic hydrogenolysis, with tritylglycyl-S-acetamido-methylcysteine to give the tetrapeptide tritylglycyl-S-acetamidomethylcysteinylprolyl-Nepsilon-trifluoroacetyllsine tert-butyloxycarbonylhydrazide. The stereochemical homogeneity of the final products was assessed, after partial deprotection with aqueous 90% trifluoroacetic acid, by digestion with papain and aminopeptidase M, followed by quantitative amino acid analysis.  相似文献   
95.
The general strategy for the synthesis, by conventional procedures, of the entire sequence of porcine pancreatic secretory trypsin inhibitor II (Kazal) is discussed. The synthesis of two protected peptides corresponding to positions 2-10 and 1-10 of the proposed primary structure of the inhibitor is described. The heptapeptide free base threonyl-S-acetamidomethylcysteinylthreonylseryl-gamma-tert-butylglutamylvalylserine tert-butyloxycarbonylhydrazide (sequence 4-10) was acylated, by the azide procedure, with either the dipeptide benzyloxycarbonyl-gamma-tert-butylglutamylalanine hydrazide (sequence 2-3) or the tripeptide Nalpha-benzyloxycarbonyl-Nomega-nitroarginylglutamylala-nine hydrazide (sequence 1-3). The stereochemical homogeneity of the resulting peptides, benzyloxycarbonyl-gamma-tert-butylglutamylalanylthreonyl-S-acetamidomethyl-cysteinylthreonylseryl-gamma-tert-butylglutamylvalylserine tert-butyloxycarbonylhydrazide and Nalpha-benzyloxycarbonyl-Nomega-nitroarginylglutamylalanylthreonyl-S-acetamido-methylcysteinylthreonylseryl-gamma-tert-butylglutamylvalylserine tert-butyloxycarbonyl-hydrazide, was assessed, after partial deprotection with liquid hydrogen fluoride, by digestion with aminopeptidase M followed by quantitative amino acid analysis.  相似文献   
96.
Synthesis is described of the partially protected octapeptide tert-butyloxycarbonyl-gamma-tert-butylglutamylasparaginyl-N-trifluoroacetyllysyl-N-trifluoracetyllysylarginyl-Ngamma-4,4'-dimethoxybenzhydryglutaminylthreonylproline corresponding to positions 36-43 of the amino acid sequence of porcine pancreatic secretory trypsin inhibitor II. The tetrapeptide free base arginyl-Ngamma-4,4'-dimethoxybenzhydrylglutaminylthreonylproline was acylated, by the azide proceedure, with the tripeptide benzyloxycarbonyl-asparaginyl-N-trifluoroacetyllsyl-N-trifluoroacetyllysine hydrazide. The resulting protected heptapeptide was partially deblocked by catalytic hydrogenation and reacted with alpha-1-succinimidyl-gamma-tert-butyl tert-butyloxycarbonylglutamate. The stereochemical homogeneity of the ensuing octapeptide was assessed, after partial deprotection with aqueous 90% trifluoroacetic acid, by digestion with papain and aminopeptidase M followed by quantitative amino acid analysis.  相似文献   
97.
Synthesis is described of the partially protected nonapeptide tert-butyloxycarbonyl-valylleucylisoleucylglutaminyl-N-trifluoroacetyllsylserylglycylprolyl-S-acetamido-methylcysteine corresponding to positions 44-52 of the amino acid sequence of porcine pancreatic secretory trypsin inhibitor II. The hexapeptide free base glutaminyl-N-trifluoroacetyllsylserylglycylprolyl-S-acetamidomethylcysteine, prepared by two alternative routes, was acylated by the azide procedure, with the tripeptide tert-butyloxycarbonylvalylleucylisoleucine hydrazide. The stereochemical homogeneity of the resulting nonapeptide was assessed, after partial deprotection by treatment with aqueous 90% trifluoroacetic acid, by digestion with papain and aminopeptidase M followed by quantitative amino acid analysis.  相似文献   
98.
We report here on 3 familial whole-arm translocations (WATs), namely the 8th instance of t(1;19)(p10;q10) and 2 novel exchanges: t(9;13)(p10;q10) and t(12;21)(p10;q10). The exchanges (1;19) and (12;21) were ascertained through a balanced carrier, whereas the t(9;13) was first diagnosed in a boy with a trisomy 9p syndrome and der(9p13p). Results of FISH analyses with the appropriate α-satellite probes were as follows. Family 1, t(1;19): the D1Z5 probe gave a strong signal on both the normal chromosome 1 and the der(1q19p) as well as a weak signal on the der(1p19q). Family 2, t(9;13): the centromere-9 alphoid and D13Z1/D21Z1 probes under standard stringency gave no signal on the der(9p13p) in both the proband and a carrier brother, whereas the der(9q13q) was labelled only with the centromere-9 alphoid repeat in the latter; yet, this probe under low stringency revealed a residual amount of alphoid DNA on the der(9p13p) in the carrier. Family 3, t(12;21): the D12Z3 probe gave a signal on the normal chromosome 12 and the der(12p21q), whereas the D13Z1/D21Z1 repeat labelled the der(12q21p), the normal chromosome 21, and both chromosomes 13. Out of 101 WATs compiled here, 73 are distinct exchanges, including 32 instances between chromosomes with common alphoid repeats. Moreover, 7/9 of recurrent WATs involved chromosomes from the same alphoid family. Thus constitutional WATs appear to recur more frequently than other reciprocal exchanges, often involve chromosomes with common alphoid repeats, and can mostly be accounted for the great homology in alphoid DNA that favours mispairing and illegitimate nonhomologous recombination.  相似文献   
99.
An experimental study was designed to investigate the efficacy of BMAP-27, a compound of the cathelicidin family, in neutralizing Escherichia coli 0111:B4 lipopolysaccharide (LPS) in bile duct-ligated mice. Main outcome measures were: endotoxin and TNF-alpha concentrations in plasma, evidence of bacterial translocation in blood and peritoneum, and lethality. Adult male BALB/c mice were injected intraperitoneally with 2 mg/kg E. coli 0111:B4 LPS 1 week after sham operation or bile duct ligation (BDL). Six groups were studied: sham with placebo, sham with 120 mg/kg tazobactam-piperacillin (TZP), sham with 1 mg/kg BMAP-27, BDL with placebo, BDL with 120 mg/kg TZP, and BDL with 1mg/kg BMAP-27. After LPS, TNF-alpha plasma levels were significantly higher in BDL mice compared to sham-operated animals. BMAP-27 achieved a significant reduction of plasma endotoxin and TNF-alpha concentration when compared with placebo- and TZP-treated groups. On the other hand, both TZP and BMAP-27 significantly reduced the bacterial growth compared with saline treatment. Finally, LPS induced 60% and 55% lethality in BDL placebo- and TZP-treated treated mice and no lethality in sham-operated mice, while only BMAP-27 significantly reduced the lethality to 10%. In light of its dual antimicrobial and anti-endotoxin properties, BMAP-27 could be an interesting compound to inhibit bacterial translocation and endotoxin release in obstructive jaundice.  相似文献   
100.
An X/Y translocation associated with Leri-Weill dyschondrosteosis (LWD) was detected in a boy and in his mother. FISH analysis with specific probes for SHOX and SRY displayed no signal on the der(X), while one signal for SHOX was detected on the normal X chromosome in the mother, and one signal each for SHOX and SRY was detected on the normal Y chromosome in the proband.  相似文献   
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