“Cryptic” dinucleotide polymorphism in the 3′ region of the factor IX gene shows substantial variation among different populations

Long tandem dinucleotide repeats composed of alternating purines and pyrimidines [RY(i)] are abundant and highly polymorphic. Simple RY(i) are predominately composed of one tandem repeat of a dinucleotide sequence. In contrast, cryptic RY(i [cRY(i)] are composed of multiple short dinucleotide repeats. Herein, we describe the racial distribution of alleles for a polymorphic cRY(i) in the factor IX gene. Allele I is absent in Asians, whereas allele III is rare or absent in Caucasians or blacks. A polymorphic cRY(i) analyzed previously shows even more dramatic variation among racial groups, hinting that a battery of cRY(i) might have utility in assessing the racial origin of a DNA sample.     

Effect of morphine and abstinence syndrome on [3H]bromoxidine binding to α2-adrenoreceptors in rat brain

At 4 days after the implantation of two subcutaneous 75 mg morphine pellets in the back skin, rats were morphine-dependent. In the three layers studied in the occipital cortex we found that the values of the ₂-adrenergic agonist [³H]bromoxidine binding increased with respect to animals implanted with placebo pellets. Typical behavioral and physiological symptoms of the abstinence syndrome appeared 30 minutes after administration of naloxone, [³H]bromoxidine binding values being similar to those obtained in animals implanted with placebo pellets. The pattern of response of the [³H]bromoxidine binding was similar in the hippocampus and the superficial gray layer of the superior colliculus of the mesencephalon, but the differences were not statistically significant in these areas. This paper concludes that exist brain regional differences in the ₂-adrenoreceptors response under morphine-treatment and possibly under naloxone-induced morphine abstinence syndrome.     

Genetics and biochemistry of phenol degradation byPseudomonas sp. CF600

Pseudomonas sp. strain CF600 is an efficient degrader of phenol and methylsubstituted phenols. These compounds are degraded by the set of enzymes encoded by the plasmid locateddmpoperon. The sequences of all the fifteen structural genes required to encode the nine enzymes of the catabolic pathway have been determined and the corresponding proteins have been purified. In this review the interplay between the genetic analysis and biochemical characterisation of the catabolic pathway is emphasised. The first step in the pathway, the conversion of phenol to catechol, is catalysed by a novel multicomponent phenol hydroxylase. Here we summarise similarities of this enzyme with other multicomponent oxygenases, particularly methane monooxygenase (EC 1.14.13.25). The other enzymes encoded by the operon are those of the well-knownmeta-cleavage pathway for catechol, and include the recently discoveredmeta-pathway enzyme aldehyde dehydrogenase (acylating) (EC 1.2.1.10). The known properties of thesemeta-pathway enzymes, and isofunctional enzymes from other aromatic degraders, are summarised. Analysis of the sequences of the pathway proteins, many of which are unique to themeta-pathway, suggests new approaches to the study of these generally little-characterised enzymes. Furthermore, biochemical studies of some of these enzymes suggest that physical associations betweenmeta-pathway enzymes play an important role. In addition to the pathway enzymes, the specific regulator of phenol catabolism, DmpR, and its relationship to the XylR regulator of toluene and xylene catabolism is discussed.     

Aluminum alters calcium transport in plasma membrane and endoplasmic reticulum from rat brain

Calcium is actively transported into intracellular organelles and out of the cytoplasm by Ca²⁺/Mg²⁺-ATPases located in the endoplasmic reticulum and plasma membranes. We studied the effects of aluminum on calcium transport in the adult rat brain. We examined ⁴⁵Ca-uptake in microsomes and Ca²⁺-ATPase activity in microsomes and synaptosomes isolated from the frontal cortex and cerebellum of adult male Long-Evans rats. ATP-dependent⁴⁵Ca-uptake was similar in microsomes from both brain regions. The addition of 50-800 μM AICI₃ resulted in a concentration-dependent inhibition of ⁴⁵Ca-uptake. Mg²⁺-dependent Ca²⁺-ATPase activity was significantly lower in synaptosomes compared to microsomes in both frontal cortex and cerebellum. In contrast to the uptake studies, AICI³ stimulated Mg²⁺-dependent Ca²⁺-ATPase activity in both microsomes and synaptosomes from both brain regions. To determine the relationship between aluminum and Mg²⁺, we measured ATPase activity in the presence of increasing concentrations of Mg²⁺ or AICI³. Maximal ATPase activity was obtained between 3 and 6 mM Mg²⁺. When we substituted AICI³ for Mg²⁺, ATPase activity was also stimulated in a concentration-dependent manner, but to a greater extent than with Mg²⁺. One interpretation of these data is that aluminum acts at multiple sites to displace both Mg²⁺ and Ca²⁺, increasing the activity of the Ca²⁺-ATPase, but disrupting transport of calcium.     

Three inhibitor types from wheat endosperm are differentially active against α-amylases of Lepidoptera pests

Crude α-amylase preparations from seven Lepidoptera pests were susceptible to inhibition by salt-soluble proteins of bread wheat (Triticum aestivum L.) endosperm. Protein fractions that corresponded to tetrameric, dimeric, and monomeric wheat α-amylase inhibitors, were decreasingly effective against the insect α-amylase activity. To further confirm these results, purified inhibitors were tested against an α-amylase preparation fromEphestia kuehniella (Zeller). This preparation showed decreased activity when increasing amounts of an heterotetrameric inhibitor (reconstituted from its isolated subunits WTAI-CM2, -CM3 and -CM16) were assayed. Activity was only partially inhibited by homodimeric (WDAI-1, synonym 0.53; WDAI-2, synonym 0.19) and monomeric (WMAI-1, synonym 0.28) inhibitors.     

Naphthalenesulfonamide derivatives ML9 and W7 inhibit catecholamine secretion in intact and permeabilized chromaffin cells

The role of protein phosphorylation in catecholamine secretion from bovine adrenomedullary chromaffin cells was studied using different protein kinase inhibitors. Naphthalenesulfonamide derivatives as ML9 and ML7, more specific for the myosin light chain kinase, and the calmodulin antagonist W7 inhibited catecholamine secretion 20 and 40% respectively in digitonin-permeabilized chromaffin cells. ML9 also decreased calcium evoked protein phosphorylation of different proteins including tyrosine hydroxylase in permeabilized cells. These naphthalenesulfonamide derivatives showed also an effect in intact cells, ML9 and W7 produced 50% inhibition in catecholamine secretion and⁴⁵Ca²⁺ uptake, however H8 had no effect. The partial [³H]nitrendipine binding displacement of these drugs to adrenomedullary membranes suggests that these sulfonamide derivatives could interact directly with L-type calcium channels in intact cells. The results obtained in permeabilized cells suggest a possible role of protein phosphorylation in the regulation of catecholamine secretion in chromaffin cells.The abbreviations used are ML9 1-(5-Chloronaphthalene-1-sulfonyl)1H-hexahydro-1,4-diazepine hydrochloride - ML7 1-(5-Iodonaphthalene-1-sulfonyl)-1H-hexahydro-1,4 diazepine hydrochloride - H7 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride - H8 N-[2-(methylamino)ethyl]-5-isoquinolinesulfonamide dihydrochloride - W7 N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride - PKI protein kinase A inhibitor - HEPES N-(2-hydroxyethylpiperazine-N-(2 ethanesulfonic acid) - PIPES piperazine-N, N-bis (2-ethanesulfonic acid) - EGTA [ethylene-bis (oxyethylenenitrilo)] tetraacetic acid - SDS sodium dodecyl sulphate - PAGE polyacrylamide gel electrophoresis - DMEM Dulbecco's Modified Eagle's medium - MLC myosin light chain - MLCK myosin light chain kinase - TH tyrosine hydroxylase     

Comparison of European and US biological indicators for ethylene oxide sterilization

Summary Biological indicators (BIs) are used to monitor ethylene oxide (EO) gas sterilization processes for medical devices. Several European and United States BIs for EO sterilization were evaluated for resistance according to both United States Pharmacopeia (USP) XXI and United Kingdom's (UK) tests for D-values. US BIs areB. subtilis var. niger spores on paper strips or disc carriers while European BIs use aluminum strips, quartz sand, or cotton yarn. Numerous BIs per run and runs per lot, as well as 2–3 different lots of BIs from each manufacturer, were examined. Both British and US BIs met their respective label claims for rates of inactivation when tested against British and USP EO test parameters, respectively. However, Danish BIs, on cotton yarn or quartz sand, were not inactivated following USP specifications during the exposure dwell times tested (600 mg L^–1 EO, 54°C, 60% RH, 0–110 min). The Danish BIs will require further testing in order for us to determine if theirB. subtilis spores are unusually resistant to EO or if the spore carrier substrates protect the spores from the sterilizing gas. In conclusion, the British and American BIs for EO sterilization are equivalent in resistance despite differences in carrier substrate, recovery conditions, calculation methods for D-values, and the labeled sterilization conditions for use.     

Parasitism byAphidius ervi (Hym.: Aphidiidae): Preference for pea aphid and blue alfalfa aphid (Hom.: Aphididae) and competition withA. Smithi

The pea aphidAcyrthosiphon pisum (Harris) and the blue alfalfa aphidA. kondoi Shinji are pests of alfalfaMedicago sativa L. worldwide. The parasitoidAphidium ervi Haliday attacks both species andA. smithi is host specific to pea aphid Experiments were conducted to determine the preference ofA. ervi forA. pisum andA. kondoi at three densities of hosts using the percentages of parasitism and superparasitism, and the distribution of eggs among hosts as criteria. Also examined was the outcome of competition between the two parasitoids when exposed to the same hosts. A. ervi attacks moreA. pisum when provided alone (no choice test) and when provided together in equal numbers withA. kondoi (choice test). There was no significant difference in the number of progeny produced by either parasitoid when a female of each species was introduced simultaneously into the same test unit containingA. pisum hosts. The effects of the pathogenPandora neoaphidis on this competition is reviewed.     

Pattern-based clustering of daily weigh-in trajectories using dynamic time warping

“Smart”-scales are a new tool for frequent monitoring of weight change as well as weigh-in behavior. These scales give researchers the opportunity to discover patterns in the frequency that individuals weigh themselves over time, and how these patterns are associated with overall weight loss. Our motivating data come from an 18-month behavioral weight loss study of 55 adults classified as overweight or obese who were instructed to weigh themselves daily. Adherence to daily weigh-in routines produces a binary times series for each subject, indicating whether a participant weighed in on a given day. To characterize weigh-in by time-invariant patterns rather than overall adherence, we propose using hierarchical clustering with dynamic time warping (DTW). We perform an extensive simulation study to evaluate the performance of DTW compared to Euclidean and Jaccard distances to recover underlying patterns in adherence time series. In addition, we compare cluster performance using cluster validation indices (CVIs) under the single, average, complete, and Ward linkages and evaluate how internal and external CVIs compare for clustering binary time series. We apply conclusions from the simulation to cluster our real data and summarize observed weigh-in patterns. Our analysis finds that the adherence trajectory pattern is significantly associated with weight loss.