Identification of non-amplifying CYP21 genes when using PCR-based diagnosis of 21-hydroxylase deficiency in congenital adrenal hyperplasia (CAH) affected pedigrees

Steroid 21-hydroxylase deficiency is among the most common inborn errors of metabolism in man. Characterization of mutations in the 21- hydroxylase gene (CYP21) has permitted genetic diagnosis, facilitated by the polymerase chain reaction (PCR). The most common mutation is conversion of an A or C at nt656 to a G in the second intron causing aberrant splicing of mRNA. Homozygosity for nt656G is associated with profoundly deficient adrenal cortisol and aldosterone synthesis, secondary hypersecretion of adrenal androgens, and a severe form of congenital adrenal hyperplasia (CAH) characterized by ambiguous genitalia and/or sodium wasting in newborns. During the course of genetic analysis of CYP21 mutations in CAH families, we and others have noticed a number of relatives genotyped as nt656G homozygotes, yet showing no clinical signs of disease. A number of lines of evidence have led us to propose that the putative asymptomatic nt656G/G individuals are incorrectly typed due to dropout of one haplotype during PCR amplification of CYP21. For prenatal diagnosis, we recommend that microsatellite typing be used as a supplement to CYP21 genotyping in order to resolve ambiguities at nt656.      

Directional transport and integration of donor DNA in Haemophilus influenzae transformation.

DNA transport and integration in Haemophilus influenzae transformation was studied with a plasmid clone of homologous DNA (pCML6). Our results indicate that: (i) donor DNA enters specialized membranous extensions on the cell surface, which we have termed "transformasomes"; (ii) linear DNA undergoes degradation upon exiting transformasomes; and (iii) DNA without a free end remains within transformasomes and is not degraded. By comparing the fate of label from uniformly labeled versus middle-labeled DNA, it appears that donor DNA undergoes degradation from an end prior to recombining with the chromosome. Using donor DNA with covalently closed termini (hairpin ends) prevents efficient exit from transformasomes. When one hairpin is removed, exit of donor DNA is shown to be directional from the free end, with preferential homologous integration of the 3' strand from that end.     

Effects of allyl methyl trisulfide on glutathione S‐transferase activity and BP‐induced neoplasia in the mouse

Allyl methyl trisulfide (AMT), a constituent of garlic oil, was studied for its effects on glutathione S‐transferase (GST) activity and on benzo[a]pyrene (BP)‐induced neoplasia of the forestomach and lungs of female A/J mice. AMT induced increased GST activity in the forestomach, small bowel mucosa, liver, and lung. The forestomach and small bowel mucosa responded to a single low dose of AMT (3.0 μmol) given by oral intubation, whereas liver and lung were less reactive. A dose schedule of two administrations of 15 μmol AMT given 48 hours apart gave close‐to‐maximum induction in all four tissues and was chosen for investigation of its inhibitory effects. With this dose schedule, AMT produced an inhibition of BP‐induced neoptasia of the forestomach as shown by a greater than 70% reduction in the number of tumors found at the completion of the experiment. Inhibition of pulmonary neoplasia did not occur. AMT is a member of a new class of naturally occurring chemicals that have the capacity to inhibit chemical carcinogenesis.     

Unklare retroperitoneale und intrahepatische Raumforderungen

25j?hrige Patientin mit bekannter tuber?ser Sklerose (Adenoma sebaceum, kutanen Lipomen und Fibromen, mentaler Retardierung und Epilepsie). Station?re Aufnahme wegen intermittierender Schmerzsymptomatik im linken Mittelbauch mit Ausstrahlung in die linke Flanke. Ausführliche Eigenanamnese nicht m?glich. Klinische Untersuchung: tastbare Resistenz im linken Mittelbauch und abgeschw?chte Darmger?usche über beiden linken Quadranten. Kein Peritonismus, keine Makroh?maturie. Labor: leicht erh?hte LDH (340 U/l), ansonsten unauff?llig. Sonographie: ausgedehnte, heterogen echoreiche Raumforderung im linken Mittelbauch und der linken Flanke, die nicht zweifelsfrei einem Organ zugeordnet werden konnte. Au?erdem echoarme Raumforderung im rechten Leberlappen. Daraufhin CT-Untersuchung unter Sedierung.     

Adiponectin in renal disease: relationship to phenotype and genetic variation in the gene encoding adiponectin

BACKGROUND: The prevalence of cardiovascular disease (CVD) and inflammation is high in patients with end-stage renal disease (ESRD). Adiponectin is an adipocytokine that may have significant anti-inflammatory and anti-atherosclerotic effects. Low adiponectin levels have previously been found in patients with high risk for CVD. METHODS: In a cohort of 204 (62% males) ESRD patients aged 52 +/- 1 years the following parameters were studied: presence of CVD, body composition, plasma adiponectin (N= 107), cholesterol, triglycerides, HDL-cholesterol, serum leptin, high-sensitivity C-reactive protein (hs-CRP), urinary albumin excretion (UAE), and single-nucleotide polymorphisms (SNPs) in the apM1 gene at positions -11391, -11377, 45, and 276. Thirty-six age- (52 +/- 2 years) and gender-matched (64% males) healthy subjects served as control subjects. RESULTS: Markedly (P < 0.0001) elevated median plasma adiponectin levels were observed in ESRD patients (22.2 microg/mL), especially type 1 diabetic patients (36.8 microg/mL), compared to control subjects (12.2 microg/mL). Log plasma adiponectin correlated to visceral fat mass (R=-0.29; P < 0.01) and Log hs-CRP (R=-0.26; P < 0.01). In a stepwise (forward followed by backward) multiple regression model only type-1 diabetes (P < 0.001) and visceral fat mass (P < 0.05) were independently associated with plasma adiponectin levels. The adiponectin gene -11377 C/C genotype was associated with a lower prevalence of CVD (25 vs. 42%) compared to the G/C genotype. CONCLUSION: The present cross-sectional study demonstrates that, whereas genetic variations seem to have a minor impact on circulating adiponectin levels, lower visceral fat mass and type 1 diabetes mellitus are associated with elevated plasma adiponectin levels in ESRD patients. Furthermore, low levels of adiponectin are associated with inflammation in ESRD.     

Preparation of protected peptidyl thioester intermediates for native chemical ligation by Nα‐9‐fluorenylmethoxycarbonyl (Fmoc) chemistry: considerations of side‐chain and backbone anchoring strategies,and compatible protection for N‐terminal cysteine*,†

Abstract: Native chemical ligation has proven to be a powerful method for the synthesis of small proteins and the semisynthesis of larger ones. The essential synthetic intermediates, which are C‐terminal peptide thioesters, cannot survive the repetitive piperidine deprotection steps of N^α‐9‐fluorenylmethoxycarbonyl (Fmoc) chemistry. Therefore, peptide scientists who prefer to not use N^α‐t‐butyloxycarbonyl (Boc) chemistry need to adopt more esoteric strategies and tactics in order to integrate ligation approaches with Fmoc chemistry. In the present work, side‐chain and backbone anchoring strategies have been used to prepare the required suitably (partially) protected and/or activated peptide intermediates spanning the length of bovine pancreatic trypsin inhibitor (BPTI). Three separate strategies for managing the critical N‐terminal cysteine residue have been developed: (i) incorporation of N^α‐9‐fluorenylmethoxycarbonyl‐S‐(N‐methyl‐N‐phenylcarbamoyl)sulfenylcysteine [Fmoc‐Cys(Snm)‐OH], allowing creation of an otherwise fully protected resin‐bound intermediate with N‐terminal free Cys; (ii) incorporation of N^α‐9‐fluorenylmethoxycarbonyl‐S‐triphenylmethylcysteine [Fmoc‐Cys(Trt)‐OH], generating a stable Fmoc‐Cys(H)‐peptide upon acidolytic cleavage; and (iii) incorporation of N^α‐t‐butyloxycarbonyl‐S‐fluorenylmethylcysteine [Boc‐Cys(Fm)‐OH], generating a stable H‐Cys(Fm)‐peptide upon cleavage. In separate stages of these strategies, thioesters are established at the C‐termini by selective deprotection and coupling steps carried out while peptides remain bound to the supports. Pilot native chemical ligations were pursued directly on‐resin, as well as in solution after cleavage/purification.     

Facile solid‐phase synthesis of C‐terminal peptide aldehydes and hydroxamates from a common Backbone Amide‐Linked (BAL) intermediate*†

Abstract: C‐Terminal peptide aldehydes and hydroxamates comprise two separate classes of effective inhibitors of a number of serine, aspartate, cysteine, and metalloproteases. Presented here is a method for preparation of both classes of peptide derivatives from the same resin‐bound Weinreb amide precursor. Thus, 5‐[(2 or 4)‐formyl‐3,5‐dimethoxyphenoxy]butyramido‐polyethylene glycol‐polystyrene (BAL‐PEG‐PS) was treated with methoxylamine hydrochloride in the presence of sodium cyanoborohydride to provide a resin‐bound methoxylamine, which was efficiently acylated by different Fmoc‐amino acids upon bromo‐tris‐pyrrolidone‐phosphonium hexafluorophosphate (PyBrOP) activation. Solid‐phase chain elongation gave backbone amide‐linked (BAL) peptide Weinreb amides, which were cleaved either by trifluoroacetic acid (TFA) in the presence of scavengers to provide the corresponding peptide hydroxamates, or by lithium aluminum hydride in tetrahydrofuran (THF) to provide the corresponding C‐terminal peptide aldehydes. With several model sequences, peptide hydroxamates were obtained in crude yields of 68–83% and initial purities of at least 85%, whereas peptide aldehydes were obtained in crude yields of 16–53% and initial purities in the range of 30–40%. Under the LiAlH₄ cleavage conditions used, those model peptides containing t‐Bu‐protected aspartate residues underwent partial side chain reduction to the corresponding homoserine‐containing peptides. Similar results were obtained when working with high‐load aminomethyl‐polystyrene, suggesting that this chemistry will be generally applicable to a range of supporting materials.     

Effects of allyl methyl trisulfide on glutathione S-transferase activity and BP-induced neoplasia in the mouse

Allyl methyl trisulfide (AMT), a constituent of garlic oil, was studied for its effects on glutathione S-transferase (GST) activity and on benzo[a]pyrene (BP)-induced neoplasia of the forestomach and lungs of female A/J mice. AMT induced increased GST activity in the forestomach, small bowel mucosa, liver, and lung. The forestomach and small bowel mucosa responded to a single low dose of AMT (3.0 mumol) given by oral intubation, whereas liver and lung were less reactive. A dose schedule of two administrations of 15 mumol AMT given 48 hours apart gave close-to-maximum induction in all four tissues and was chosen for investigation of its inhibitory effects. With this dose schedule, AMT produced an inhibition of BP-induced neoplasia of the forestomach as shown by a greater than 70% reduction in the number of tumors found at the completion of the experiment. Inhibition of pulmonary neoplasia did not occur. AMT is a member of a new class of naturally occurring chemicals that have the capacity to inhibit chemical carcinogenesis.