In vivo determination of muscle-derived stem cells in rat corpus cavernosum

The aim of this in vivo study was to determine the existence of muscle-derived stem cells (MDSCs) in rat corpus cavernosum. Immunohistochemical and RT-PCR analyses were performed to determine the expression of the stem cell markers (Sca-1, Oct4, and desmin) in Sprague-Dawley (SD) rats in different age groups (10 rats in each group). Sca-1 was mainly expressed in blood vessels and cavernous sinus and demonstrated primarily cytoplasmic staining. Desmin was expressed mainly in muscle tissues and staining occurred mainly in the cytoplasm but also partially in the nucleus. An extremely small amount of double-positive stained cells (Sca-1/desmin) were detected near the cavernous sinus. Expression of the markers was significantly and negatively correlated with the age of the rats (P < 0.05). The RT-PCR results showed that the expression levels of Sca-1 and desmin significantly decreased with age (P < 0.05). Correlation analysis indicated that the expression of Sca-1 and desmin were significantly and negatively correlated with the age of rats (r = -0.929, P < 0.05). The present study provides evidence for the existence of MDSCs in rat corpus cavernosum. MDSCs may have therapeutic potential in the treatment of organic erectile dysfunction.

Study on mating ecology and sex ratio of three internally ovipositing fig wasps of Ficus curtipes

Studies on mating ecology and sex allocation in fig-parasitizing wasps ovipositing from outside the fig have given valuable insights into known factors that are responsible for the theory of sex ratio. Similarly, internally ovipositing fig-parasitizing wasps and fig-pollinating wasps provide interesting models for comparative analysis. In addition to the fig-pollinating wasp Eupristina sp., we found that Ficus curtipes hosts two species of internally ovipositing fig-parasitizing wasps: D. yangi and Lipothymus sp. Eupristina sp. males showed less aggression. Eupristina sp. has wingless males that mate only within the natal patch, providing excellent examples of full local-mate competition. D. yangi males showed high levels of aggression and lethal combat. D. yangi has winged males but mate mostly within the natal patch. Only a few matings occur after male dispersal. Its sex ratio was lower than the prediction of partial local mate competition theory. Wingless male Lipothymus sp., which mate partly after dispersal, did not present fatal fight. Therefore, the mating behaviour of D. yangi and Lipothymus sp. did not follow predicted patterns, based on wing morph. The mating pattern of D. yangi and Lipothymus sp. should follow the partial local mate competition theory. Furthermore, there was not a significant correlation between the proportion of males and the proportion of fruit parasitized in both winged D. yangi males and wingless Lipothymus sp. males.

Enhancement of cephalosporin C production by cultivation of Cephalosporium acremonium M25 using a mixture of inocula

AIMS

To enhance the productivity of Cephalosporin C (CPC) by cultivation of Cephalosporium acremonium M25 using a mixture of inocula.

METHODS AND RESULTS

Inoculum age was classified into three stages (early, intermediate and late) by image analysis. A mixture of inocula, according to the inoculum ages, was used for efficient production of CPC in the main culture. The most effective mixing ratio of inocula for CPC production in shake flasks was a 3 : 7 volume ratio of early- and late-stage inocula. This was also the case in a 1.5 l stirred-tank reactor. CPC productivity was enhanced by about 32% and 34% when using an inoculum mixture in the shake flask and 1.5 l stirred-tank reactor, respectively.

CONCLUSION

The morphological characteristics of C. acremonium M25 in the seed culture were quite different according to inoculum age. The compromise of different ages of inoculum showed better production of CPC.

SIGNIFICANCE AND IMPACT OF THE STUDY

The productivity of CPC was enhanced considerably when using mixed inocula. The results of this study can be applied to fungal cultures for efficient production of various metabolites.

[The phylogeny of 5 Chinese peculiar Parnassius butterflies using noninvasive sampling mtDNA sequences]

This paper employs nonivasive sampling DNA sequencing technique for estimating molecular phylogeny of 5 Chinese peculiar Parnassius Butterflies. Of 433bp mitochondrial cytochrome b DNA sequences, A% + T% was 75.4%, and 40 nucleotide sites were substituted (about 9.24%). The molecular phylogenetic tree constructed by parsimony method suggests that Parnassius acco is closely related to Parnassius baileyi; Parnassius apollo, Parnassius orlears, and Parnassius simo are independent branches respectively. Parnassius simo is divergent earlier. The result is identical with that of morphology.

Regulatory factors associated with synthesis of the osmolyte glycine betaine in the halophilic methanoarchaeon Methanohalophilus portucalensis

The halophilic methanoarchaeon Methanohalophilus portucalensis can synthesize de novo and accumulate beta-glutamine, Nepsilon-acetyl-beta-lysine, and glycine betaine (betaine) as compatible solutes (osmolytes) when grown at elevated salt concentrations. Both in vivo and in vitro betaine formation assays in this study confirmed previous nuclear magnetic resonance 13C-labelling studies showing that the de novo synthesis of betaine proceeded from glycine, sarcosine, and dimethylglycine to form betaine through threefold methylation. Exogenous sarcosine (1 mM) effectively suppressed the intracellular accumulation of betaine, and a higher level of sarcosine accumulation was accompanied by a lower level of betaine synthesis. Exogenous dimethylglycine has an effect similar to that of betaine addition, which increased the intracellular pool of betaine and suppressed the levels of Nepsilon-acetyl-beta-lysine and beta-glutamine. Both in vivo and in vitro betaine formation assays with glycine as the substrate showed only sarcosine and betaine, but no dimethylglycine. Dimethylglycine was detected only when it was added as a substrate in in vitro assays. A high level of potassium (400 mM and above) was necessary for betaine formation in vitro. Interestingly, no methylamines were detected without the addition of KCl. Also, high levels of NaCl and LiCl (800 mM) favored sarcosine accumulation, while a lower level (400 mM) favored betaine synthesis. The above observations indicate that a high sarcosine level suppressed multiple methylation while dimethylglycine was rapidly converted to betaine. Also, high levels of potassium led to greater amounts of betaine, while lower levels of potassium led to greater amounts of sarcosine. This finding suggests that the intracellular levels of both sarcosine and potassium are associated with the regulation of betaine synthesis in M. portucalensis.

Two newly identified mutations (Thr233Ile and Leu152Met) in partially adenosine deaminase-deficient (ADA-) individuals that result in differing biochemical and metabolic phenotypes

Deficiency of adenosine deaminase (ADA-) results in autosomal recessive immunodeficiency disease of varying severity. Partial ADA- [ADA deficiency in erythrocytes (RBCs) but substantial ADA in non-RBCs] has also been identified, primarily by population screening of healthy adults in Africa and newborns in New York State. Normal immune function and/or minimal elevations of toxic metabolites in childhood suggested that partial ADA deficiency was benign and therefore that six mutations identified in partially ADA-deficient newborns and expressing 8-80% of normal ADA in non-RBCs were not pathogenic. However, the lowest activity mutation (Arg211Cys) has now been reported in patients with adult-onset immunodeficiency. We have now molecularly and biochemically studied two additional individuals whom we found to represent opposite ends of the spectrum of partial ADA deficiency as to biochemical abnormalities and age of ascertainment. Homozygosity for a newly identified Leu152Met mutation expressing considerably less activity than the pathogenic Arg211Cys mutation was found in a currently healthy 10-year-old Afghanistani child (ascertained at birth). He had the highest accumulation of the metabolite dATP among 13 partially ADA-deficient patients studied, but considerably lower than in those with immunodeficiency. Homozygosity for a newly identified Thr233Ile mutation expressing somewhat greater ADA activity than Arg211Cys was found in a healthy young adult Kung individual, associated with very low metabolite concentrations. Biochemical findings and a family history suggestive of immunodeficiency in prior offspring support the idea that the Leu152Met mutation could result in disease in homozygous individuals challenged by severe environmental insult or in heterozygosity with a null mutation. The pathogenicity of the Thr233Ile mutation, as well as a previously described Ala215Thr mutation with relatively lower activity is less likely but will only be determined by long-term observation of individuals carrying these mutations. Although, in contrast to other partial mutations, neither of these two mutations are at CpG hot spots, the frequency of CpG mutations remains high for partial mutations but is also similarly high in ADA- immunodeficient patients (5/8 vs 12/21).

Spontaneous in vivo reversion to normal of an inherited mutation in a patient with adenosine deaminase deficiency

Somatic mosaicism in genetic disease generally results from a de novo deleterious mutation during embryogenesis. We now describe a somatic mosaicism due to the unusual mechanism of in vivo reversion to normal of an inherited mutation. The propositus was an adenosine deaminase-deficient (ADA-) child with progressive clinical improvement and unexpectedly mild biochemical and immunologic abnormalities. Mosaicism due to reversion was evidenced by absence of a maternally transmitted deleterious mutation in 13/15 authenticated B cell lines and in 17% of single alleles cloned from blood DNA, despite retention of a maternal 'private' ADA polymorphism linked to the mutation. Establishment of significant somatic mosaicism following reversion to normal could modify any disorder in which revertant cells have a selective advantage.

Somatic mosaicism for a newly identified splice-site mutation in a patient with adenosine deaminase-deficient immunodeficiency and spontaneous clinical recovery

Absent or severely reduced adenosine deaminase (ADA) activity produces inherited immunodeficiency of varying severity, with defects of both cellular and humoral immunity. We report somatic mosaicism as the basis for a delayed presentation and unusual course of a currently healthy young adult receiving no therapy. He was diagnosed at age 2 1/2 years because of life-threatening pneumonia, recurrent infections, failure of normal growth, and lymphopenia, but he retained significant cellular immune function. A fibroblast cell line and a B cell line, established at diagnosis, lacked ADA activity and were heteroallelic for splice-donor-site mutation in IVS 1 (+1GT-->CT) and a missense mutation (Arg101Gln). All clones (17/17) isolated from the B cell mRNA carried the missense mutation, indicating that the allele with the splice-site mutation produced unstable mRNA. In striking contrast, a B cell line established at age 16 years expressed 50% of normal ADA; 50% of ADA mRNA had normal sequence, and 50% had the missense mutation. Genomic DNA contained the missense mutation but not the splice-site mutation. All three cell lines were identical for multiple polymorphic markers and the presence of a Y chromosome. In vivo somatic mosaicism was demonstrated in genomic DNA from peripheral blood cells obtained at 16 years of age, in that less than half the DNA carried the splice-site mutation (P < .002, vs. original B cell line). Consistent with mosaicism, erythrocyte content of the toxic metabolite deoxyATP was only minimally elevated. Somatic mosaicism could have arisen either by somatic mutation or by reversion at the site of mutation. Selection in vivo for ADA normal hematopoietic cells may have played a role in the return to normal health, in the absence of therapy.

Homozygosity for a missense mutation (G20R) associated with neonatal onset adenosine deaminase-deficient severe combined immunodeficiency (ADA-SCID)

Mutations at the adenosine deaminase (ADA) locus can result in varying degrees of immunodeficiency, including rapidly fulminant severe combined immunodeficiency (SCID) as well as a slowly progressive immunodeficiency not diagnosed until later in childhood. Genetic heterogeneity is a factor in the clinical heterogeneity. We have now identified, by direct sequencing of PCR-amplified genomic DNA, a G to A transition at a CpG dinucleotide predicting a glycine to arginine substitution at codon 20 (G20R). The mutation, in homozygosity, was associated with neonatal-onset rapidly fatal SCID. Consistent with homozygosity, the child was derived from a small isolated inbred community in Newfoundland. The mutation abolishes a site for the restriction enzyme BamHI and can be simply detected by agarose gel electrophoresis following amplification of exon 2 from genomic DNA and digestion with BamHI. The majority of ADA missense mutations can now be detected by similar amplification and enzyme digestion. We demonstrated that the G20R mutation is deleterious since introduction of the mutation into a normal ADA minigene abolished enzyme activity, as determined by transient expression in monkey kidney (Cos) cells. The amino acid substitution occurs in an area of the molecule conserved from Escherichia coli to man and that, as shown by crystallographic analysis, is involved in the binding of Zn2+ at the catalytic site. Although the mutation is in a CpG dinucleotide, known "hotspots" for G to A transitions, it was not found in a series of 43 additional ADA- chromosomes. Identification of mutations in additional ADA- patients with immunodeficiency of varying severity should further define the role that genotype plays in determining the extent of immunologic dysfunction.

An Asp8Asn substitution results in the adenosine deaminase (ADA) genetic polymorphism (ADA 2 allozyme): occurrence on different chromosomal backgrounds and apparent intragenic crossover

We have now determined the molecular genetic basis for the common biochemical polymorphism at the adenosine deaminase (ADA) locus. The ADA*2 allele contains a G to A transition at nt22 (relative to the ATG) that results in substitution of asparagine for aspartic acid at codon 8 (Asp8Asn). Introduction of the nucleotide substitution into an ADA 1 cDNA and transfection into monkey kidney (Cos) cells confirmed that the mutation resulted in expression of an enzyme that comigrated with the naturally occurring ADA 2 allozyme. The substitution of neutral asparagine for anionic aspartic acid is consistent with the more cathodal electrophoretic migration of ADA 2 as compared with ADA 1. The nucleotide substitution was found on at least two different genetic backgrounds, suggesting independent recurrence of the mutation. Consistent with independent recurrence, the G to A transition is at a CpG dinucleotide and represents a type of mutation that occurs with high frequency. We have also unexpectedly identified a probable intragenic crossover in the very large first intron that is rich in repetitive DNA sequences.

Severe combined immunodeficiency of reduced severity due to homozygosity for an adenosine deaminase missense mutation (Arg253Pro)

Genetic deficiency of adenosine deaminase (ADA) results in varying degrees of immunodeficiency, including neonatal onset severe combined immunodeficiency (ADA- SCID) and milder, later onset immunodeficiency. We have determined the molecular basis of disease in a child from a consanguineous mating with ADA- SCID of clinically and biochemically reduced severity, diagnosed at 15 months of age and characterized by retention of more immunologic function than is typical of the fulminant neonatal onset type. The course was notable for an early predominance of bacterial infections and eosinophilia. In contrast to its absence in most ADA- SCIDs, residual ADA activity (1-2% of normal) could be detected in EBV-transformed B cells. Consistent with the increased residual ADA, excretion of the substrate deoxyadenosine and accumulation of the toxic metabolite deoxyATP were less than seen in ADA- SCID patients with fulminant disease. Sequence analysis of cDNA revealed a G853C transversion, predicting a substitution of proline for arginine at codon 253 (Arg253Pro). The parents were heterozygous and the child was homozygous for the mutation, as shown by sequence analysis of amplified genomic DNA. Transient expression of mutant cDNA in Cos cells revealed an electrophoretically abnormal, more negatively charged ADA with 1-2% of normal activity. These observations are consistent with replacement of positively charged arginine by proline, the lower accumulation of toxic metabolites, and the milder phenotype. By contrast, transient expression of a Gly216Arg mutant cDNA, associated, when homozygous, with neonatal onset ADA-SCID, did not reveal ADA activity. Mutations such as Arg253Pro, which retain residual activity of monomeric ADA, should be dominant for ameliorating the phenotype in patients carrying two different allelic mutations. Identification of additional similar mutations may be significant in evaluating the goals for and efficacy of current trials of gene and gene product replacement.

Novel deletion and a new missense mutation (Glu 217 Lys) at the catalytic site in two adenosine deaminase alleles of a patient with neonatal onset adenosine deaminase- severe combined immunodeficiency

Mutations at the adenosine deaminase (ADA) locus result in a spectrum of disorders, encompassing a fulminant neonatal onset severe combined immunodeficiency (SCID) and childhood onset immunodeficiency, as well as apparently normal immune function. The extent of accumulation of the toxic metabolite, deoxyATP, correlates directly with severity of disease. We have now determined the mutations on both alleles of a child with fulminant, neonatal onset ADA- SCID and accumulation of extremely high concentrations of deoxyATP. The genotype was consistent with the severely affected phenotype. One allele carried a large deletion that arose by non-homologous recombination and included the first five exons and promoter region. The second allele carried a missense mutation (G649A) resulting in replacement of Glu217, an amino acid involved in the catalytic site, by Lys and predicting a major alteration in charge. Expression of the mutant cDNA in Cos cells confirmed that the mutation abolished enzyme activity. We have previously reported that a missense mutation at the preceding codon is similarly associated with neonatal onset ADA- SCID and accumulation of extremely high deoxyATP. These findings suggest that genotype-phenotype correlations may be apparent for ADA- SCID, despite the role that random variation in exposure to environmental pathogens may play in the initial phenotype. Such genotype-phenotype correlations may be important to consider in evaluating results of ongoing trials of "gene" and enzyme replacement therapy.

Novel deletion and a new missense mutation (Glu 217 Lys) at the catalytic site in two adenosine deaminase alleles of a patient with neonatal onset adenosine deaminase- severe combined immunodeficiency

Mutations at the adenosine deaminase (ADA) locus result in a spectrum of disorders, encompassing a fulminant neonatal onset severe combined immunodeficiency (SCID) and childhood onset immunodeficiency, as well as apparently normal immune function. The extent of accumulation of the toxic metabolite, deoxyATP, correlates directly with severity of disease. We have now determined the mutations on both alleles of a child with fulminant, neonatal onset ADA- SCID and accumulation of extremely high concentrations of deoxyATP. The genotype was consistent with the severely affected phenotype. One allele carried a large deletion that arose by non-homologous recombination and included the first five exons and promoter region. The second allele carried a missense mutation (G649A) resulting in replacement of Glu217, an amino acid involved in the catalytic site, by Lys and predicting a major alteration in charge. Expression of the mutant cDNA in Cos cells confirmed that the mutation abolished enzyme activity. We have previously reported that a missense mutation at the preceding codon is similarly associated with neonatal onset ADA- SCID and accumulation of extremely high deoxyATP. These findings suggest that genotype-phenotype correlations may be apparent for ADA- SCID, despite the role that random variation in exposure to environmental pathogens may play in the initial phenotype. Such genotype-phenotype correlations may be important to consider in evaluating results of ongoing trials of "gene" and enzyme replacement therapy.