Characterization of Nine Novel Mutations in the CD40 Ligand Gene in Patients with X-Linked Hyper IgM Syndrome of Various Ancestry

X-linked immunodeficiency with hyper-IgM (HIGMX-1) is a rare disorder caused by defective expression of the CD40 ligand (CD40L) by activated T lymphocytes, resulting in inefficient T-B cell cooperation and failure of B cells to undergo immunoglobulin isotype switch. In the present work, we describe nine patients of various ancestry who bear different mutations in the X chromosome–specific CD40L gene. Two of the mutations were nonsense mutations, one each resulting in premature stop codons at amino acid residues 39 and 140. Three patients had single point missense mutations, one each at codons 126, 140, and 144. Another patient had a 4-bp genomic deletion in exon 2, resulting in a frameshift and premature termination. Three patients showed insertions, one each of 1, 2, and 4 nt, probably because of polymerase slippage, resulting in frameshift mutation and premature termination. Overall, these observations confirm the heterogeneity of mutations in HIGMX-1. However, the identification of two patients whose mutation involves codon 140 (previously shown to be altered in two other unrelated subjects) suggests that this may be a hotspot of mutation in HIGMX-1. In two additional patients with clinical and immunological features indistinguishable from canonical HIGMX-1, no mutation was detected in the coding sequence, in the 5' flanking region, or in the 3' UTR.     

Distribution and abundance of house-dust mites (Acarina: Pyroglycphidae) in Rome,Italy

For the first time in Rome, house-dust mite infestation was studied in 90 randomly selected houses. In each house, mite infestation was assessed in three sites: mattress, bedroom and living room. In total, 87.8% of the sampled houses were positive for dust mites. In the houses infested, 11.4% showed densities of >100 mites/g of dust, 15.2% registered densities between 50 and 99, and in the remaining houses (73.4%), the densities were between 1 and 49 mites/g dust. The percentages of infested houses were positively correlated with the relative humidity (RH) values (r=0.89,P=0.02). At the lowest range of RH (between 46 and 50), the infestation was 50% and at the highest range of RH (between 73 and 78) it was 100%. The mattress was significantly the most infested (71.1%) of the tested sites. Only wool and spring mattresses were infested, and they did not show any significant differences in mite concentrations.Dermatophagoides farinae was the most abundant species (53.1%), followed byGlycyphagus domesticus (34.5%),D. pteronyssinus (5.2%), andEuroglyphus maynei (0.2%);D. farinae was also the most frequent species (56.9%). The remaining specimens (7.0%) were predator species commonly found in houses. The prevalence ofD. farinae in Rome is discussed.     

IgM anti-hepatitis C virus in patients with chronic non-A, non-B hepatitis and their relationship to viral replication

Patients with hepatitis C virus (HCV) infection may have different patterns of antibody response to various structural and non-structural viral antigens. We have correlated the serological patterns to the clinical features of chronic infection and to viral replication in 68 HCV-Ab-positive patients with chronic liver disease at different stages (19 with cirrhosis-hepatocellular carcinoma, 38 with chronic active hepatitis and 11 with chronic persistent hepatitis). Serum samples from each patient were assayed for HCV-IgM by enzyme immunoassay and for HCV-RNA by the polymerase chain reaction using primer sets derived from the 5'-non-coding region. The prevalence of HCV-IgM was high (54 patients (79.4%)) and the study showed a good correlation between high values of anti-HCV-IgM and the presence of HCV-RNA in serum, since HCV-RNA was detected in 35 of the 54 IgM-positive patients (64.8%) and notably in 19 of the 20 subjects with high levels of specific IgM. Conversely, all the 35 sera containing HCV-RNA were also reactive for HCV-IgM, while none of the HCV-IgM-negative sera was HCV-RNA reactive. Positivity rates for both HCV-RNA and IgM anti-HCV were higher in the more advanced stages of disease; thus, the clinical pattern of HCV chronic hepatitis seems to be strictly related to the serological pattern and the presence of HCV-RNA.     

Sex differences in platelet thromboxane and arterial prostacyclin production in control and n-6 fatty acid supplemented rats

Sex differences in eicosanoid production in platelets and vessel walls have been studied in control and n-6 fatty acid supplemented rats. In platelet rich plasma (PRP) of control female rats, arachidonic acid (AA) levels in phospholipids (PL), thromboxane B₂ (TxB₂) formation following collagen stimulation and aggregatory responses to collagen were higher than in PRP of male rats. 6 keto PGF_1α release from PRP-perfused isolated aortas were the same for both sexes, but the antiaggregatory activity of the wall was higher in males than in females, in association with a greater sensitivity of male platelets to prostacyclin.The administration of n-6 fatty acid supplements increased AA level in PL, TxB₂ production and aggregation only in male platelets. Production of 6 keto PGF_1α and the antiaggregatory activity of aortic walls were reduced after dietary treatment in males, but biochemical and functional parameters were not correlated in females.The results indicate complex sex-related differences in fatty acid metabolism and eicosanoid production, and in responses to n-6 dietary fatty acids in platelets and the vascular system in the rat.     

Freeze-preservation of rice cells: A physiological study of freeze-thawed cells

Rice ( Oryza sativa L.) cells returning to in vitro culture after preservation at superlow temperature in liquid nitrogen are characterized by a number of physiological alterations. These include: reduction in respiration and glucose uptake, loss of intracellular potassium, decrease in the cellular level of key metabolites (ATP, glucose-6-phosphate and pyruvate) and fragility of protoplasts following the action of cell wall-degrading enzymes.
Nevertheless, cell growth resumes after a short lag phase (2–4 days) with an actual 70–100% cell survival, thus indicating that the observed damage is not lethal and can be repaired in a short time.     

Inhibition of elongation and H+ and K+ transport by the phosphodiesterase inhibitor aminophylline in plant tissue

Aminophylline, an inhibitor of cyclic nucleotide phosphodiesterase (EC 3.1.4.17), inhibits elongation and correlated H⁺ and K⁺ transport in embryos of Haplopappus gracilis and in pea internode segments. Moreover, the drug strongly inhibits the stimulation of these processes by fusicoccin and indole-3-acetic acid and reduces passive permeability of the membrane. The possible mechanisms of action of aminophylline are discussed.Abbreviations cAMP adenosine 3:5-cyclic monophosphate - FC fusicoccin - IAA indole-3-acetic acid - MES 2-N-morpholinoethanesulfonic acid - PDE cyclic nucleotide phosphodiesterase     

Determination of cytoplasmic receptors for specific steroid hormones. II) Androgen receptor

Cytoplasmic receptors for 5 alpha-dihydrotestosterone (3H-DHT) were determined in normal and hypertrophic human prostate using the slightly modified DCC method we previously standardized for 17beta-estradiol-receptor. Incubations were always performed at 0 degree C for 1 hr. Discrimination between 3H-DHT binding to cytoplasmic receptor and to Sex Hormone Binding Globulin (SHBG) was achieved on the basis of binding affinity, thermolability and pattern of specificity by various steroid hormones. In particular, 5 beta-DHT did not bind to cytoplasmic receptor, while it did to SHBG.     

Determination of cytoplasmic receptors for specific steroid hormones. III) Progestin receptor

A method for determining cytoplasmic progesterone receptor was standardized in normal human endometrium comparing two different tracers, 3H-progesterone (3H-P) and 3H-medroxyprogesterone acetate (3H-MAP), a synthetic progestin which does not bind to Corticosteroid Binding Globulin (CBG). Receptor assays were performed as previously reported for 17beta-estradiol receptor, with slight modifications: incubation lasted 1 hr at 0 degree C, followed by 5 min DCC exposure under the same conditions. When 3H-P was employed as tracer, blanks performed with cold MAP gave similar results as using cortisol in incubation tubes and progesterone and cortisol in blanks. 3H-MAP was a good tracer for progesterone receptor because it neither bound to CBG nor to androgen or cortisol receptors; it had very high affinity and specificity for P-R; it was not metabolized by cytosol at 0 degree C and, finally, it detected receptor amounts quite comparable to those obtained using 3H-P.     

Incorporation of 18O2 into brain serotonin in vivo as a procedure for estimating turnover: a feasibility study in animals.

Serotonin (5HT) containing ¹⁸0 instead of ¹⁶0 was found in brain after exposing rats to an atmosphere of ¹⁸0₂. The ¹⁸0 incorporation appeared linear with time and 22% of the 5HT in striatum contained ¹⁸0 after one hour of exposure. ¹⁸0 entered 5HT by enzymatic reaction rather than by isotope exchange as treatment with p-chlorophenylalanine, to block tryptophan hydroxylase, prevented incorporation, while more ¹⁸0-5HT than normal was found in brain after treatment with pargyline, to block monoamine oxidase. Our studies suggest that the incorporation of ¹⁸0₂ into brain 5HT might be a feasible approach for evaluating 5HT turnover in animals and with some modification might be applied in man.