bluuebunny/crossref_metadata_2025 huggingface dataset:
The relationship between adolescent obesity and pelvis dimensions in adulthood: a retrospective longitudinal study
Authors: Novak Jan M. , Bruzek Jaroslav , Zamrazilova Hana , Vankova Marketa , Hill Martin , Sedlak Petr
Published: May 2020

Background

The effect of fat tissue on a developing individual is fundamentally different from the effect on an adult. Several changes caused by obesity during sexual maturation have an irreversible and severe negative effect (lower fertility, reduced final height, type 2 diabetes mellitus) even for those who have subsequently lost weight. Our study was focused on monitoring the skeletal structure substantially influenced by sex hormones—the pelvis. The adult pelvis is strongly sexually dimorphic, which is not the case for the juvenile pelvis; skeletal differences between sexes are not so prominent and start to manifest with the onset of puberty. Evidence from animal models and case studies of treatment of gender dysphoria suggests that estrogens have a stimulatory effect on the growth plates present on the pelvis, leading to morphological change. Male obesity, especially in puberty, is connected with hypogonadism, manifesting in low levels of testosterone, and high levels of estrogens. The goal of our study was to evaluate the influence of obesity during adolescence on the morphology of the adult pelvis in the context of androgen and estrogen status.

Sample and Methods

Our sample consists of 238 individuals (144 females, 94 males) observed after an 8 year follow-up (mean age during enrollment 15.2 years, follow-up 23.3 years). Anthropometry and body composition using bioimpedance analysis (BIA) were obtained. During the follow-up, saliva samples from male participants were also collected to estimate testosterone and estradiol levels using the salivary ELISA kit (Salimetrics LLC, State College, PA, USA).

Results

The body fat (percentage of body fat estimated using BIA) was strongly positively associated with relative pelvic breadths in adulthood (males r = 0.64; females r = 0.56, both with p < 0.001). Adulthood pelvic breadth was a highly sensitive (0.81) and specific (0.74) retrospective marker of obesity during adolescence. The complex regression model (with reduction of dimensionality) including testosterone, estradiol to testosterone ratio and body fat (adolescent and adulthood) was able to describe 54.8% variability of pelvic breadth among males.

Discussion

We observed that adults with a history of obesity from adolescence tend to have a wider dimension of the bony pelvis in adulthood. Based on the parameters of the adult pelvis, the history of obesity can be determined with satisfactory sensitivity and specificity (<70%). One of the explanations for this observation can be the influence of relatively elevated estrogens levels connected with excessive adiposity leading to a wider pelvis. However, the biomechanical stress connected with elevated body mass also has to be considered, as does the influence of physical activity and gait pattern on the skeletal build.
Higher carbon sequestration potential and stability for deep soil compared to surface soil regardless of nitrogen addition in a subtropical forest
Authors: Liao Chang , Li Dong , Huang Lin , Yue Pengyun , Liu Feng , Tian Qiuxiang
Published: May 2020

Background

Labile carbon input could stimulate soil organic carbon (SOC) mineralization through priming effect, resulting in soil carbon (C) loss. Meanwhile, labile C could also be transformed by microorganisms in soil as the processes of new C sequestration and stabilization. Previous studies showed the magnitude of priming effect could be affected by soil depth and nitrogen (N). However, it remains unknown how the soil depth and N availability affect the amount and stability of the new sequestrated C, which complicates the prediction of C dynamics.

Methods

A 20-day incubation experiment was conducted by adding 13C labeled glucose and NH4NO3 to study the effects of soil depth and nitrogen addition on the net C sequestration. SOC was fractioned into seven fractions and grouped into three functional C pools to assess the stabilization of the new sequestrated C.

Results

Our results showed that glucose addition caused positive priming in both soil depths, and N addition significantly reduced the priming effect. After 20 days of incubation, deep soil had a higher C sequestration potential (48% glucose-C) than surface soil (43% glucose-C). The C sequestration potential was not affected by N addition in both soil depths. Positive net C sequestration was observed with higher amount of retained glucose-C than that of stimulated mineralized SOC for both soil depths. The distribution of new sequestrated C in the seven fractions was significantly affected by soil depth, but not N addition. Compared to deep soil, the new C in surface soil was more distributed in the non-protected C pool (including water extracted organic C, light fraction and sand fraction) and less distributed in the clay fraction. These results suggested that the new C in deep soil was more stable than that in surface soil. Compared to the native SOC for both soil depths, the new sequestrated C was more distributed in non-protected C pool and less distributed in biochemically protected C pool (non-hydrolyzable silt and clay fractions). The higher carbon sequestration potential and stability in deep soil suggested that deep soil has a greater role on C sequestration in forest ecosystems.
Orthodontic Pain and Patients’ Quality of Life: Patient Experiences and Provider Assessments
Authors: Tauheed Sanam , Khan Erum Behroz , Islam Zafar , Khan Shoaib , Butt Saima Akram , Shaikh Attiya , Fida Mubassar
Published: May 2020

Objectives: To compare orthodontic pain and its Influence on quality of patient’s life as perceived by them with that assessed by their orthodontic care providers.

Materials and Methods: It was crosses sectional study involving 75 patients attending the orthodontic clinic and14 orthodontic care providers from September to October 2010. Patients aged 16 and older, receiving fixed orthodontic treatments were included. Patients and orthodontists scored pain during different orthodontic procedures using a qualitative pain intensity scale which graded pain for different orthodontic procedures. Oral health related quality of life (OHRQoL) was assessed by means of a 4-point likert scale to measure the influence of orthodontic treatment related pain on different aspects of life.

Results: For change of consistency of diet (p=0.02) statistically significant difference was observed between mean ranks of patients and orthodontists. For pain during record taking, higher mean ranks were reported for patients aged between 20-30 years (p = 0.01) whereas for pain after separator placement, patients aged above 30 had higher mean ranks (p = 0.05).

Conclusions: Orthodontists can accurately estimate the degree of pain their patients’ experience.

Significant proportions of patients experience substantial degrees pain during the visits, subsequent to orthodontic visits and pain due to fixed orthodontic appliance therapy transiently affects patients’ OHRQoL.
Qualitative Analysis of the Phytochemical Contents of Different Anatomical Parts of Ripe Solanum aethiopicum Linneaus Fruits
Authors: Tunwagun David Adesoye , Akinyemi Olalekan Amos , Ayoade Titilayo Eunice , Oyelere Sunday Faith
Published: May 2020

Aims: To determine qualitatively the amount of alkaloids, saponin, tannin, volatile oil, phenol and flavonoids in the different anatomical parts of ripe Solanum aethiopicum Linn fruits.

Methodology: Solanum aethiopicum Linn fruits were purchased from Sabo market, Ogbomoso, Nigeria. The fruits were separated with a razor into four (4) anatomical parts (the epicarp, mesocarp, endocarp, and seed) after washing with distilled water. 1gram of each anatomical parts of the fruit were soaked in 20mls of distilled water,1% volume per volume (v/v), 2% v/v, 3%v/v, 4%v/v and 5%v/v of ethanol, ethylacetate and methanol separately. The mixtures were left for 24 hours after which they were sieved to obtain the extracts. The presence of alkaloid, tannin, saponin, volatile oil, phenol and flavonoid were determined qualitatively in the extracts at selected concentrations.

Results: The results obtained showed that alkaloids are more concentrated in the mesocarp of Solanum aethiopicum Linn; volatile (essential) oil is more pronounced in the mesocarp and endocarp of Solanum aethiopicum Linn; saponin is confirmed in all anatomical parts of the fruit at reasonable quality except in the seed; tannin is found to be moderately present only in the aqueous extract of mesocarp of Solanum aethiopicum Linn fruit while the presence of phenol and flavonoids were confirmed in trace amount at few tested concentrations of the extracts.

Conclusion: Taken together, the presence of a variety of phytochemicals in the different anatomical parts of Solanum aethiopicum Linn fruit indicate that the fruit might be pharmacologically active against a number of diseases. However, this should be subjected to subsequent researches.
Acetyl glyceryl ether phosphorylcholine (platelet‐activating factor) mediates heightened metabolic activity in macrophages
Authors: Hartung Hans-Peter
Published: July 2002

The phospholipid mediator AGEPC (acetyl glyceryl ether phosphorylcholine) was examined for its effects on guinea pig peritoneal macrophages. At a concentration of 10−9 ‐10−6 M, AGEPC evoked release of prostaglandin E (PGE) and thromboxane B2 (TXB2) from albumin‐elicited macrophages. It also triggerd generation of O−
2 by Corynebacterium parvum‐induced cells. Moreover, it caused augmented spreading of macrophages. The calmodulin antagonis W‐7 attenuated AGEPC‐mediated O−
2 production and cell spreading whereas prostanoid synthesis was enhanced. These novel actions of AGEPC on the major cellular component of the inflammatory process attest to its role as a potent mediator of immunoinflammatory responses.
Two‐quantum selective laser scission of polyadenilic acid in the complementary complex with a dansyl derivative of oligothymidilate
Authors: Benimetskaya L.Z. , Bulychev N.V. , Kozionov A.L. , Lebedev A.V. , Nesterikhin Yu.E. , Novozhilov S.Yu. , Rautian S.G. , Stockmann M.I.
Published: July 2002

Nonathymidilate was synthesized containing the chromophore (dansyl) group linked to its 5'‐phosphate. In the presence of this compound the polyadenilic acid molecules are split by the radiation (power density J ⪖ 70 MW/cm2) of a nitrogen laser, while under the same conditions poly(C) and poly(U) are hardly affected. This selective optically non‐linear effect was predicted and is explained in terms of radiativeless transfer of two‐quantum excitation of the chromophore which is fixed in poly(A) molecule due to the formation of the complementary complex with nonathylmidilate
Purification of membrane‐bound cytochromes and a photoactive P840 protein complex of the green sulfur bacterium Chlorobium limicola f. thiosulfatophilum
Authors: Hurt Eduard C. , Hauska Günter
Published: July 2002

A photoactive P840 protein complex and a fraction enriched in cytochrome b from chromatophores of Chlorobium limicola f. thiosulfatophilum are described. The former is identical in pigment composition to the ‘core complex’ of Prostecochloris aestuarii [(1983) Biochim. Biophys. Acta 725, 361–367]. It consists of 3 major polypeptides. The dominating one, of 65 kDa and carrying bacteriochlorophyll, is the P840 reaction center protein. It is probably very similar to the P700 reaction center protein of chloroplasts and cyanobacteria. A 24‐kDa protein could be identified as an ascorbate‐reducible cytochrome c‐550.5. The third polypeptide of 32 kDa might be a Rieske‐type FeS protein. The cytochrome b fraction consists of 2 polypeptides of 42 kDa, representing cytochrome b‐562, and 24 kDa, representing ascorbate‐reducible cytochrome c‐550.5 again. Conditions can be varied to obtain cytochrome b‐562 in pure form. A first characterization of the components is presented.
Endopeptidase‐24.11 and aminopeptidase activity in brain synaptic membranes are jointly responsible for the hydrolysis of cholecystokinin octapeptide (CCK‐8)
Authors: Matsas Rebecca , Turner Anthony J. , Kenny A.John
Published: July 2002

Endopeptidase‐24.11 (EC 3.4.24.11) from pig kidney hydrolysed CCK‐8 (sulphated) at two distinct sites: Asp‐Tyr(SO3H)‐Met‐Gly↓Trp‐Met‐Asp↓PheNH2. Under initial conditions, the splitting of the Asp7‐Phe8NH2 bond proceeded 4‐times more rapidly than the Gly4‐Trp5 bond. Pig brain striatal synaptic membranes attacked this substrate at the same sites and this activity was inhibited by phosphoramidon. However, other products were detected even in the presence of phosphoramidon. One of these products was identified as free tryptophan. Since their formation was inhibited by bestatin, one or more membrane aminopeptidases is also implicated in the degradation of CCK‐8.
Primary structure of helodermin, a VIP‐secretin‐like peptide isolated from Gila monster venom
Authors: Hoshino Minoru , Yanaihara Chizuko , Hong Yeong-Man , Kishida Satoshi , Katsumaru Yumiko , Vandermeers André , Vandermeers-Piret Marie-Claire , Robberecht Patrick , Christophe Jean , Yanaihara Noboru
Published: July 2002

The complete amino acid sequence of helodermin isolated from the venom of Gila monster was elucidated. The peptide was shown to be a basic pentatriacontapeptide amide: His‐Ser‐Asp‐Ala‐Ile‐Phe‐Thr‐Gln‐Gln‐ Tyr‐Ser‐Lys‐Leu‐Leu‐Ala‐Lys‐Leu‐Ala‐Leu‐Gln‐Lys‐Tyr‐Leu‐Ala‐Ser‐Ile‐Leu‐Gly‐Ser‐Arg‐Thr‐Ser‐Pro‐Pro‐Pro‐NH2. A high degree of sequence similarities to secretin/VIP/PHI/(PHM)/GRF from mammal and bird was observed over the entire N‐terminal 1–27 sequence. In particular, the amino acid residues in positions 3, 6 and 7 were found to be common to 9 peptides of the family. Another interesting feature of the structure of helodermin was its C‐terminal ‐Pro‐Pro‐Pro‐NH2 sequence. Isolation of helodermin was the first demonstration of the existence of a secretin/VIP‐related peptide in an animal that is neither mammal nor bird.
Inhibition by alloxan of mitochondrial aconitase and other enzymes associated with the citric acid cycle
Authors: Boquist L. , Ericsson I.
Published: July 2002

Considerable variations were found in the in vitro effect of alloxan on mouse liver enzymes associated with the citric acid cycle. The following approximative alloxan concentrations induced 50% inhibition of enzyme activity: 10−6 M for aconitase, 10−4 M for NAD‐linked isocitrate dehydrogenase, glutamate dehydrogenase, α‐ketoglutarate dehydrogenase, succinyl‐CoA synthetase and fumarase, and 10−3 M for citrate synthase and NADP‐linked isocitrate dehydrogenase. Pyruvate dehydrogenase, succinate dehydrogenase and malate dehydrogenase were not inhibited by 10−3 M alloxan. The inhibition of aconitase was competitive both when using mouse liver and purified porcine heart enzyme. The K
i values for the purified enzyme in the presence of 5 μM alloxan were 0.22 μM with citrate, 4.0 μM with cis‐aconitate and 0.62 μM with isocitrate as substrate. The high sensitivity of aconitase for inhibition by alloxan probably plays a prominent role for the toxic effects of alloxan.
Changes in the nuclear distribution of cyclin (PCNA) during S‐phase are not triggered by post‐translational modifications that are expected to moderately affect its charge
Authors: Bravo Rodrigo , Celis Julio E.
Published: July 2002

Indirect immunofluorescence studies of HeLa cells using PCNA autoantibodies specific for cyclin have revealed striking changes in the nuclear localization of this protein during S‐phase. Two‐dimensional gel electrophoretic analysis of the [32P] orthophosphate and [35S] methionine labelled proteins from synchronized cells showed that phosphorylation, or other post‐translational modifications that are expected to moderately affect the charge of cyclin (acetylation, glycosylation, sialylation, etc.) are not likely part of the mechanism(s) triggering the migration of this protein.
An ATP‐dependent and inositol trisphosphate‐sensitive Ca2+ pool linked with microfilaments of the parietal cell
Authors: Tsunoda Yasuhiro
Published: July 2002

In digitonin‐permeabilized parietal cells, myo‐inositol 1,4,5‐trisphosphate (Ins P3) or Ca2+ ionophore (A23187) increased the cytosolic Ca2+ concentration due to the intracellular Ca2+ release. Addition of ATP decreased the cytosolic Ca2+ concentration due to the rapid Ca2+ re‐uptake into the same or similar pool which releases Ca2+ from a non‐mitochondrial location (measured by quin2/AM and 45Ca2+). Cytochalasin B failed to increase the cytosolic Ca2+ concentration in response to Ins P3 or A23187 and even failed to decrease the cytosolic Ca2+ concentration in response to ATP. This implies that the ATP‐dependent and Ins P3‐sensitive Ca2+ pool is linked with the microfilaments of the parietal cell. In intact parietal cells, A23187 increased the amino[14C]pyrine accumulation (an index of acid secretion), that was independent of medium Ca2+. This increase of acid secretion was inhibited by the pretreatment with cytochalasin B. This suggests that medium Ca2+‐independent acid secretion (by A23187) is regulated by the microfilaments. Therefore, there is a close relationship between the intracellular Ca2+ metabolism, microfilaments and acid secretion
A specific immunological probe for the major myelin proteolipid
Authors: Trifilieff E. , Luu B. , Nussbaum J.L. , Roussel G. , de los Monteros A.Espinosa , Sabatier J.M. , Van Rietschoten J.
Published: July 2002

Major myelin proteolipid (MMPL, also called PLP) and DM‐20 are the two major intrinsic membrane proteins of CNS myelin. A specific immunological probe was obtained for MMPL by raising antibodies against the synthetic tridecapeptide 117–129 of MMPL. Antibodies against this peptide reacted with the MMPL but dit not cross react with DM‐20, while both proteolipids had been shown previously to be recognized by antibodies directed against the C‐terminal hexapeptide of MMPL. This is in accordance with previous findings showing that DM‐20 diners only from MMPL by a deletion of residues 100–140 (±few units). Furthermore, this site‐specific immunological probe also recognizes MMPL in its native form in oligodendrocytes in primary glial cell cultures.
The phorbol ester TPA inhibits cyclic AMP phosphodiesterase activity in intact hepatocytes
Authors: Irvine Fiona , Pyne Nigel J. , Houslay Miles D.
Published: July 2002

Treatment of intact hepatocytes with the phorbol ester 12‐O‐tetradecanoyl phorbol 13‐acetate (TPA) potentiated the ability of glucagon to increase intracellular cyclic AMP concentrations. This effect was dose‐dependent upon TPA, exhibiting an EC50 of 0.39 and such activation was observed at both saturating and sub‐saturating concentrations of glucagon. However, this stimulatory effect of TPA was completely abolished by the presence of the cyclic AMP phosphodiesterase inhibitor 1‐isobutyl‐3‐methylxanthine, when TPA now inhibited the glucagon‐stimulated increase in intracellular cyclic AMP concentrations. It is suggested that, as well as inhibiting glucagon‐stimulated adenylate cyclase activity, TPA also inhibits cyclic AMP phosphodiesterase activity in intact hepatocytes. Treatment of either hepatocyte homogenates or purified cyclic AMP phosphodiesterase with TPA failed to show any direct inhibitory effect of TPA on activity showing that TPA did not exert any direct inhibitory action on phosphodiesterase activity. However, homogenates made from hepatocytes that had been pre‐treated with TPA did show a reduced cyclic AMP phosphodiesterase activity. It is suggested that TPA might inhibit cyclic AMP phosphodiesterase activity through phosphorylation by C‐kinase.
Phosphorylation of small subunit plays a crucial role in the regulation of RuBPCase in moss and spinach
Authors: Kaul Ratnum , Saluja Daman , Sachar R.C.
Published: July 2002

RuBPCase has been purified to electrophoretic homogeneity from moss and spinach. On denaturing SDS‐polyacrylamide gels the purified enzyme revealed two discrete bands, thereby indicating the presence of large and small subunits. The phosphoprotein nature of RuBPCase was proved by in vivo labelling of enzyme with [32P]orthophosphate. Autoradiographic analysis of 32P‐labelled RuBPCase on SDS‐PAG demonstrated that phosphorylation was restricted to the small subunit. Dephosphorylation of purified RuBPCase with alkaline phosphatase resulted in a dramatic decline (70% decrease) in the biological activity of the enzyme. Fractionation of the dephosphorylated enzyme on denaturing gels revealed only the presence of large subunits of RuBPCase. Thus it became evident that dephosphorylation of RuBPCase brings about the dissociation of small subunits from the catalytic large subunits (octamer). The dephosphorylated small subunits were isolated as dimers. These results clearly indicate that phosphorylation of small subunits is mandatory for the reconstitution of holoenzyme and hence crucial for the activation of RuBPCase.
Amino acid neurotransmitters in the CNS
Authors: Erecińska Maria , Troeger Melody B.
Published: July 2002

D‐Aspartate exchange, defined as amino acid‐stimulated D‐[3H]aspartate efflux, was investigated in a preparation of rat brain synaptosomes. The efflux of radiolabelled D‐aspartate was found to be enhanced by micromolar concentrations of externally added D‐ and L‐aspartate, L‐glutamate, L‐cysteate.and L‐cysteinesulphinate. The stimulation of release by external amino acids followed Michaelis‐Menten kinetics; the apparent K
m values (in μM) were: 14.65 ± 0.98 for D‐aspartate; 8.00±1.5 for L‐aspartate; 22.31 ± 1.62 for L‐glutamate; 6.76 ± 0.3 for L‐cysteate and 7.89± 1.23 for L‐cysteinesulphinate. The νmax values for efflux were 2.16–4.06 per mg protein. The exchange process was found to require external NaCl but was very little affected by increase in the external [K+]. The demonstration of exchange as a part of the transport process provides support for the suggestion that in synaptosomal preparations a substantial portion of influx and efflux of amino acid neurotransmitters occurs via a reversible membrane carrier.
Differential kinetics of rat insulin I and II processing in rat islets of Langerhans
Authors: Gishizky Mikhail L. , Grodsky Gerold M.
Published: July 2002

Synthesis and processing of radiolabelled rat insulin I and II were studied by pulse‐labelling freshly isolated rat islets with [3H]leucine and chasing in 2 mM glucose for up to 270 min (which minimized insulin secretion, < 1%/h). Islet samples were taken during the chase period and analyzed for their rat insulin I and II content by high‐performance liquid chromatography. Prior to 60 min chase rat insulin I accounted for > 85% of the radiolabelled insulin present. With longer periods of chase, the relative percentage of rat insulin II progressively increased so that by completion of proinsulin to insulin processing the two labelled rat insulins were present in the same proportion as the relative immunoreactive content, approx. 60:40% insulin I/insulin II. Thus, although islets synthesize the two insulins in proportion to their relative immunoreactive content, rat insulin I and II are processed with different kinetics.
Purification and characterization of a 32‐kDa phospholipase A2 inhibitory protein (lipocortin) from human peripheral blood mononuclear cells
Authors: Rothhut Bernard , Comera Christine , Prieur Benoît , Errasfa Mourad , Minassian Garo , Russo-Marie Françoise
Published: July 2002

A 32‐kDa protein was isolated from human monocytes after calcium precipitation and chromatography. The protein activity was assessed by the inhibition of soluble phospholipase A2, (PLA2). This in vitro inhibitory effect on phospholipases A2 was found only with negatively charged phospholipids. The protein was also able to inhibit cellular PLA2, in mouse thymocytes. The biochemical properties and amino acid composition strongly suggest that the protein shares similarities with endonexin. Using a neutralizing monoclonal antibody against rat lipocortin, we found a cross‐reactivity with the 32‐kDa protein. According to the biochemical and immunological properties, we propose to relate this PLA2, inhibitory protein from human monocytes to lipocortin.
Photosystem II disorganization and manganese release after photoinhibition of isolated spinach thylakoid membranes
Authors: Virgin Ivar , Styring Stenbjo¨rn , Andersson Bertil
Published: July 2002

The activity, the protein content and the manganese properties of photosystem II have been compared after photoinhibition of isolated thylakoid membranes. The results show a concomitant disappearance of the oxygen evolving activity and the ability to form the S2‐state multiline EPR signal. The D1‐protein is degraded in a subsequent event which closely correlates to release of manganese from the thylakoid membranes.
Synthesis of diadenosine 5′,5‴‐P1,P4‐tetraphosphate by organellar and cytoplasmic phenylalanyl‐tRNA synthetases of Euglena gracilis
Authors: Krauspe R. , Parthier B. , Wasternack C.
Published: July 2002

Purified phenylalanyl‐tRNA synthetases present in chloroplasts, mitochondria and cytoplasm of green and bleached Euglena gracilis strains, respectively, are able to synthesize diadenosine 5′,5‴‐P1,P4‐tetraphosphate (Ap4A). Ap4A synthesis is strictly dependent on zinc ions. This is the first evidence that chloroplasts should be able to synthesize Ap4A. Synthesis of Ap4A by phenylalanyl‐tRNA synthetases of the three compartments of a plant cell or by other enzymes such as Ap4A phosphorylase is discussed.
Yeast vacuolar aminopeptidase yscI
Authors: Cueva Rosario , García-Alvarez Nieves , Suárez-Rendueles Paz
Published: July 2002

The structural gene, APE1, (LAP4), for the vacuolar aminopeptidase I of Saccharomyces cerevisiae was cloned with the aid of a staining technique which permitted monitoring of aminopeptidase activity in yeast colonies. Genetic linkage data demonstrate that integrated copies of the cloned gene map to the APEI locus. The nucleotide sequence of the cloned gene was determined. The open reading frame of APEI consists of 514 codons and, therefore, encodes a larger protein (MW 57 003) than the reported mature aminopeptidase yscI (MW 44 800), suggesting that proteolytic processing must occur. A 1.75‐kb mRNA, which is made in substantial amounts only when yeast cells have exhausted the glucose supply, was identified.
Different isozymes of cytochrome c oxidase are expressed in bovine smooth muscle and skeletal or heart muscle
Authors: Anthony G. , Stroh A. , Lottspeich F. , Kadenbach B.
Published: July 2002

Cytochrome c oxidase (COX) was isolated from bovine smooth muscle (rumen), and compared with the enzyme from bovine liver, heart and skeletal muscle. A new isozyme of COX was found to be expressed in smooth muscle, which differs from the isozyme in liver and heart or skeletal muscle. SDS‐PAGE as well as N‐terminal amino acid sequencing of separated subunits from gel bands revealed the expression of the liver isoforms for subunits VIa and VIII and of the heart isoform for subunits VIIa in COX from smooth muscle.
The serine acetyltransferase from Escherichia coli
Authors: Wigley Dale B. , Derrick Jeremy P. , Shaw William V.
Published: July 2002

An expression vector has been constructed which increases the expression of serine acetyltransferase (SAT) from E. coli to 17% of the soluble cell protein. A novel purification procedure, using dye‐affinity chromatography, allows purification of SAT to homogeneity. The enzyme has been crystallised from polyethylene glycol, in the presence of L‐cysteine (an inhibitor of SAT). The crystals which diffract to beyond 3.0 Å resolution are of the tetragonal spacegroup P41212(or P43212) with cell dimensions a = b = 123 Å, c = 79 Å. Since ultracentrifugation and gel‐filtration experiments indicate that purified SAT is a tetramer, there appears to be one‐half tetramer in the asymmetric unit (V
m = 2.55 Å3/Da).
Regulation of the Na+ ‐K+ pump activity and estimation of the reserve capacity in intact rat peritoneal mast cells
Authors: Knudsen T. , Johansen T.
Published: July 2002

Evidence is provided that regulation of the Na+ ‐K+ pump activity in rat peritoneal mast cells occurs mainly through stimulation of the pump from inside the plasma membrane by sodium. It is demonstrated that there is a large reserve capacity for the exchange of intracellular sodium with extracellular potassium in these cells. The maximal pump activity was estimated to be 3230 cells per min and K
m for extracellular potassium was 1.5 mM.
Molecular cloning of the β‐subunit of the Na,K‐ATPase in the brine shrimp, Artemia
Authors: Bhattacharyya Kalyan K. , Bergstrom Ellen E. , Hokin Lowell E.
Published: July 2002

A cDNA encoding the β‐subunit of the Na,K‐ATPase of brine shrimp (Artemia) has been cloned. Its nucleotide sequence and predicted amino acid sequence have been determined. The amino acid sequence shows considerable divergence from that of chicken, dog, human, pig, rat, sheep, Torpedo, and Xenopus. This is not entirely unexpected since brine shrimp is a ‘fast clock’ organism which diverged from the precursor of the vertebrates 0.5–1.0 billion years ago. However, a highly hydrophobic putative transmembrane domain and the carboxy‐terminal domain show considerable conservation. The relatively small degree of conservation in the β‐subunit of Anemia should provide information about the functional significance of this protein.
Complete 1H and 13C assignment of Lys and Leu sidechains of staphylococcal nuclease using HCCH‐COSY and HCCH‐TOCSY 3D NMR spectroscopy
Authors: Baldisseri D.M. , Pelton J.G. , Sparks S.W. , Torchia D.A.
Published: July 2002

Complete proton and carbon sidechain assignments are reported for 22 lysine and II leucine residues in staphylococcal nuclease, an enzyme with 149 residues. These assignments are readily obtained in a direct manner from the correlations observed in the 3D HCCH‐COSY and HCCH‐TOCSY spectra and the unknown protein backbone assignments. These assignments open the way to detailed of the sidechain structure and dynamics at the active site, in the hydrophobic core and on the surface of the protein.
Structure of coiled β‐β‐hairpins and β‐β‐corners
Authors: Efimov A.V.
Published: July 2002

Two types of super‐secondary structure, coiled β‐β‐hairpins and β‐β‐corners, are considered in this paper. A β‐β‐corner can be represented as a long β‐β‐hairpin folded orthogonally on itself so that the strands, when passing from one layer to the other. rotate in a right‐handed direction about an imaginary axis. It is shown that a β‐β‐hairpin. forming a coiled coil structure or a β‐β‐corner, is right‐handed when viewed from the concave side. These unique arrangements of β‐strands in the coiled β‐β‐hairpins and β‐β‐corners are of particular value in protein modelling and prediction.
The cytochrome chain of mitochondria exhibits variable H+/e− stoichiometry
Authors: Papa S. , Capitanio N. , Capitanio G. , De Nitto E. , Minuto M.
Published: July 2002

A study is presented of the ←H+/e− stoichiometry for H+ pumping by the cytochrome chain in isolated rat liver mitochondria under level‐flow and steady‐state conditions. It is shown that the ←H+/e− stoichiometry for the cytochrome chain varies under the influence of the flow rate and transmembrane ΔμH+. The rate‐dependence is shown to be associated with cytochrome c oxidase, whose ←H+/e− ratio varies from 0 to 1, whilst the ←H+/c− ratio for the span covered by cytochrome c reductase is invariably 2.
Production of endothelin‐1 and big‐endothelin‐1 by pleural mesothelial cells
Authors: Kuwahara Masayoshi , Kuwahara Maki , Suzuki Nobuhiro
Published: July 2002

Immunoreactive endothelin‐1 (ET‐1) and big‐endothelin‐1 (big‐ET‐1) were detected in conditioned medium of cultured rat pleural mesothelial cells by using sensitive sandwich‐type enzyme immunoassays. The amount of both ET‐1 and big‐ET‐1 increased time‐dependently. In both instances, maximal amount was detectable in conditioned medium obtained after 72 h in culture (ET‐1: 117.1 ± 30.1 pg/106 cells; big‐ET‐1: 2.4 ± 2.1 pg/106 cells). Fetal calf serum markedly stimulated the production of both ET‐1 and big‐ET‐1.
Gradient expression of Cdx along the rat intestine throughout postnatal development
Authors: Freund Jean-Noël , Boukamel Rita , Benazzouz Aziz
Published: July 2002

Rat genomic DNA was isolated by homology with Cdxl, a murine homeogene selectively expressed in intestinal cells of endodermal origin. Southern blot analysis indicated that the rat genome contains a single or a small number of closely related Cdx gene(s). A major 1.7 kb Cdx mRNA was detected in neonate, suckling and adult rats whereas a 6.5 kb mRNA was restricted to sucklings and adults. Both transcripts showed decreasing concentration from the colon towards the proximal part of the small intestine. No obvious correlation could be established with the patterns of expression of transcripts corresponding to markers of cell proliferation and cell differentiation during postnatal development.
Positional and additive effects of basic amino acids on processing of precursor proteins within the constitutive secretory pathway
Authors: Watanabe Toshio , Murakami Kazuo , Nakayama Kazuhisa
Published: July 2002

We have recently shown that the Arg/Lys‐X‐Lys/Arg‐Arg or Arg/Lys‐X‐X‐X‐Lys/Arg‐Arg sequence serves as a signal for cleavage of precursor proteins within the constitutive secretory pathway, and this cleavage is catalyzed by furin, a mammalian homolog of the yeast Kex2 protease. In this study, we further examined sequence requirements for the constitutive precursor cleavage. Based on the data concerning cleavage efficiencies of various prorenin mutants with amino acid substitution(s) around the native cleavage site expressed in CHO cells, we revised the sequence rules that govern the constitutive cleavage as follows: (i) the Arg residue at position −1 is essential; (ii) in addition to the Arg at position −1, at least two out of the three basic residues at positions −2, −4, and −6 are required for efficient cleavage (the presence of all the three basic residues results in most efficient cleavage); (iii) at position +1, a hydrophobic aliphatic amino acid is not suitable.
Bovine inositol monophosphatase
Authors: Rees-Milton K.J. , Greasley P.J. , Ragan C.I. , Gore M.G.
Published: July 2002

The inositol monophosphatase from bovine brain is inactivated by the histidine‐specific reagent diethylpyrocarbonate. Using 4 mM reagent at pH 6.5, the reaction results in the modification of 3 equivalents of histidine per polypeptide chain. The loss of activity occurs at the same rate as the slowest reacting of these residues. Site directed mutagenesis studies have been used to generate a mutated enzyme species bearing a His‐217→Gln replacement and have shown that it is the modification of histidine 217 which results in the inactivation of the enzyme.
Identification, sequence analysis, and characterization of cDNA clones encoding two granzyme‐like serine proteinases from rat duodenum
Authors: Amerik Alexander Yu. , Yarovoi Serge V. , Grigorenko Vitali G. , Antonov Vladimir K.
Published: July 2002

Clones of cDNA encoding two serine proteinases were isolated from a cDNA library prepared from rat duodenum mRNA. The deduced amino acid sequences consisted of 248 residues and possessed a high level of homology to one another and to the sequences of granzymes, cathepsin G, and mast cell proteases I and II. Analysis of the enzymes' primary structures allowed the identification of the catalytic amino acid triad and the prediction of the substrate specificity. Northern blotting experiments showed that while one of these proteinases is expressed only in duodenum, the other enzyme is present in duodenum, lung, and spleen. It is supposed that these proteinases may play an important role in the function of an organism's defence systems.
Sequence analysis of the promoter region of the rat somatostatin receptor subtype 1 gene
Authors: Hauser Frank , Meyerhof Wolfgang , Wulfsen Iris , Schönrock Christiane , Richter Dietmar
Published: July 2002

Somatostatin receptor (SSTR) subtype genes are differentially expressed in brain and various peripheral tissues. RNA blotting and semiquantitative PCR analyses have revealed low levels of SSTR1 mRNA in the gastrointestinal tract and relatively high levels in GH3 anterior pituitary cells. As a first step in the investigation of the regulation of SSTR1 gene expression, we isolated a genomic fragment that contains the promoter region and determined the transcriptional initiation site. The SSTR1 gene lacks introns and TATA and CAAT motifs, but possesses several consensus recognition sequences for the transcription factors GCF and AP‐2. The presence, also, of two Pit‐1 binding sites could explain the high SSTR1 mRNA levels in GH3 cells.
The amphipathic α‐helix concept
Authors: Cornut Isabelle , Büttner Klaus , Dasseux Jean-Louis , Dufourcq Jean
Published: July 2002

An original serie of 12‐ to 22‐residue‐long peptides was developed, they are only constituted by apolar Leu and charged Lys residues periodically located in the sequence in order to generate ideal highly amphipathic α‐helices. By circular dichroism, the peptides are proven to be mainly α‐helical in organic and aqueous solvents and in the presence of lipids. The peptides are highly hemolytic, their activity varies according to the peptide length. The 15‐, 20‐, and 22‐residue‐long‐peptides have LD50 ∼5 × 10−8 M for 107 erythrocytes, i.e. they are 5–10 times more active than melittin, and are indeed several orders of magnitude more active than magainin or mastoparan.
Ammonium‐sensitive protein kinase activity in plasma membranes of the cyanobacterium Anacystis nidulans
Authors: Rodríguez Rocío , García-González Mercedes , Guerrero Miguel G. , Lara Catalina
Published: July 2002

Cytoplasmic membranes prepared from nitrate‐grown Anacystis nidulans cells exhibit a Mg2+‐dependent protein kinase activity able to phosphorylate in vitro plasma membrane polypeptides with molecular masses of 98, 93, 83, 47, 44 and 31 kDa. The protein kinase activity was inhibited in cytoplasmic membrane preparations from nitrate‐grown cells which had been exposed to ammonium for 5 min. Parallely, ammonium exposure also resulted in a more than two‐fold activation of an alkaline phosphatase activity present in the soluble fraction. These results are discussed in relation to the well‐known inhibition by ammonium of nitrate transport activity, and a hypothesis for the regulatory mechanism involved is presented.
Metal‐catalyzed inactivation of bovine glucose‐6‐phosphate dehydrogenase — role of thiols
Authors: Maier Konrad L. , Hinze Helga , Meyer Barbara , Lenz Anke-Gabriele
Published: July 2002

The role of thiols as oxidant scavengers during inactivation of bovine glucose‐6‐phosphate dehydrogenase by metal‐catalyzed oxidation systems has been studied in vitro. Partial inactivation of the enzyme was achieved by the metal‐catalyzed oxidation systems Fe(II)/H2O2/EDTA or Fe(II)/ H2O2/ADP under specific conditions. When EDTA as chelator was present in the oxidation system, both cysteine and N‐acetylcysteine at low concentrations (0.1 – 1 mM) drastically enhanced inactivation, while cysteinyl‐glycine and glutathione did not. The thiol‐mediated inactivation was inhibitable by superoxide dismutase. Depletion of enzyme activity by cysteine was paralleled by an increase of the carbonyl content, which indicates oxidative injury. However, when EDTA as chelator was replaced by the natural chelator ADP, all thiols studied acted as antioxidants. It is therefore concluded that the nature of the chelator as a constituent of the metal‐catalyzed oxidation systems determines whether the antioxidative function of some thiols is shifted to a prooxidative function against glucose‐6‐phosphate dehydrogenase.
Comorbidity of panic disorder, phobia, and major depression
Authors: Lydiard RB
Published: July 2002

Depression and panic disorder co-occur in about one-third of people presenting with either condition. When they occur together they present diagnostic and treatment dilemmas for the clinician. However, this is a clinical problem that has been routinely ignored by researchers because of the diagnostic criteria before DSM-III-R, and the restrictive entry criteria in drug trials where patients must have one clearly defined illness.
High‐conductance channel induced by the interaction of phage lambda with its receptor maltoporin
Authors: Berrier Catherine , Bonhivers Melanie , Letellier Lucienne , Ghazi Alexandre
Published: July 2002

Bacteriophage λ that binds to liposomes bears its receptor maltoporin (LamB) and is able to inject its DNA into the internal space. During this process, the liposomes are permeabilized, suggesting that a transmembrane channel has formed (Roessner and Ihler (1986) J. Biol. Chem. 261, 386–390). This pore possibly constitutes the pathway used by λ DNA to cross the membrane. We reconstituted purified LamB from Shigella in liposomes that were incubated with λ phages. Addition of this mixture to a bilayer chamber resulted in the incorporation in planar bilayers of high‐conductance channels whose conductance, kinetics and voltage dependence were totally different from those of maltoporin channels.
The molecular peculiarities of catalase‐peroxidases
Authors: Zámocký Marcel , Regelsberger Günther , Jakopitsch Christa , Obinger Christian
Published: July 2002

In developing ideas of how protein structure modifies haem reactivity, the activity of Class I of the plant peroxidase superfamily (including cytochrome c peroxidase, ascorbate peroxidase and catalase‐peroxidases (KatGs)) is an exciting field of research. Despite striking sequence homologies, there are dramatic differences in catalytic activity and substrate specificity with KatGs being the only member with substantial catalase activity. Based on multiple sequence alignment performed for Class I peroxidases, we present a hypothesis for the pronounced catalase activity of KatGs. In their catalytic domains KatGs are shown to possess three large insertions, two of them are typical for KatGs showing highly conserved sequence patterns. Besides an extra C‐terminal copy of the ancestral hydroperoxidase gene resulting from gene duplication, these two large loops are likely to control the orientation of both the haem group and of essential residues in the active site. They seem to modulate the access of substrates to the prosthetic group at the distal side as well as the flexibility and character of the bond between the proximal histidine and the ferric iron. The hypothesis presented opens new possibilities in the rational engineering of peroxidases.
Functional consequences of disulfide bond formation in gelsolin
Authors: Allen Philip G
Published: July 2002

Gelsolin is an actin monomer binding and filament severing protein synthesized in plasma and cytoplasmic forms differing by an N‐terminal amino acid extension and a disulfide bond between Cys‐188 and Cys‐201. To determine whether this bond altered gelsolin regulation or function, oxidized and reduced plasma gelsolins were assayed for severing, monomer binding and nucleation activity at a variety of rate‐limiting calcium concentrations. The results indicate that the disulfide bond in domain 2 of gelsolin influences the transmission of information from C‐terminal regulatory sites to functional sites in the N‐terminus.
Identification of an atypical lipoprotein‐binding protein from human aortic smooth muscle as T‐cadherin
Authors: Tkachuk Vsevolod A , Bochkov Valery N , Philippova Maria P , Stambolsky Dmitry V , Kuzmenko Elena S , Sidorova Maria V , Molokoedov Alexander S , Spirov Valentin G , Resink Therese J
Published: July 2002

We have previously described an atypical lipoprotein‐binding protein of about 105 kDa (p105) in membranes of vascular smooth muscle cells (VSMCs) that is distinct from currently known lipoprotein receptors. In the present work we have developed a procedure for purification of p105 from human aortic media. Partial sequencing of purified protein has revealed identity of p105 with human T‐cadherin. Anti‐peptide antisera raised against human T‐cadherin recognized a protein spot corresponding to the purified p105 on two‐dimensional Western blots. The antisera also inhibited LDL binding to p105 on ligand blots. We conclude that the 105 kDa lipoprotein‐binding protein present in human VSMCs is T‐cadherin, an unusual glycosylphosphatidylinositol‐anchored member of the cadherin family of cell‐cell adhesion proteins.
Expression, purification and preliminary crystal analysis of the human low Mr phosphotyrosine protein phosphatase isoform 1
Authors: Marzocchini R , Bucciantini M , Stefani M , Taddei N , Thunnissen M.G.M.M , Nordlund P , Ramponi G
Published: July 2002

The genes of the human low M
r phosphotyrosine protein phosphatase (PTPase) isoforms 1 (IF1) and 2 (IF2) were isolated by screening a human placenta cDNA library, cloned in pGEX and expressed in E. coli as fusion proteins with glutathione S‐transferase. The recombinant proteins were purified by a rapid one‐step procedure allowing each enzyme to purify with high final yield and specific activity. This result is important for IF1, whose purification from natural sources is difficult, due to precipitation propensity, thus hindering structural studies. The enzymes obtained showed kinetic parameters very similar to those previously determined for the enzymes purified by classical procedures from both human erythrocytes and rat liver. These recombinant enzymes can therefore be used in place of those purified from natural sources for every purpose. IF1 and IF2 crystals were also grown. IF1 crystals were X‐ray‐grade, diffracted to better than 2.4 Å and were suitable for high resolution X‐ray structure determination.
In vitro heat effect on heterooligomeric subunit assembly of thermostable indolepyruvate ferredoxin oxidoreductase
Authors: Siddiqui Masood A , Fujiwara Shinsuke , Takagi Masahiro , Imanaka Tadayuki
Published: July 2002

Indolepyruvate ferredoxin oxidoreductase (IOR) from hyperthermophilic archaeon Pyrococcus kodakaraensis KOD1 catalyzes the oxidative decarboxylation of arylpyruvates by forming a heterooligomeric complex (α2β2). The genes iorA and iorB which encode respective α and β subunits, were coexpressed heterologously in Escherichia coli cells under anaerobic conditions. IOR activity was detected from the cell extract containing both subunits and its activity was enhanced by in vitro heat treatment prior to the assay. The iorA and iorB were expressed individually and each subunit was examined for enzymatic activity with and without heat treatment. IOR activity was detected neither from the extract of α subunit nor β subunit. The α and β subunits were mixed and then IOR activity was examined. Weak IOR activity was detected without heat treatment, however, upon heat treatment its activity was enhanced. The mixture of individually heat treated α and β subunits did not possess any IOR activity even though the mixed sample was heat treated again. IOR α and β subunits were individually purified to homogeneity, mixed with or without heat treatment and subunit assembly was examined by determining molecular mass. Upon heat treatment, inactive α and β were converted to an active high molecular weight complex (195 kDa) which corresponds to the α2β2 structure. However, the active complex was not formed without heat treatment, suggesting that high temperature environments are important for the hetero‐oligomerization of IOR subunits.
Collagen type XVI expression is modulated by basic fibroblast growth factor and transforming growth factor‐β
Authors: Grässel Susanne , Tan Elaine M.L , Timpl Rupert , Chu Mon-Li
Published: July 2002

We investigated the effects of bFGF and TGF‐β on the expression of type XVI collagen, a member of the fibril associated collagen family, in human dermal fibroblasts and arterial smooth muscle cells. We found that bFGF decreased the α1(XVI) collagen mRNA to 18–24% of the controls, while TGF‐β increased the mRNA to 150–360%. Immunoprecipitation of metabolically labeled cells revealed corresponding, but less pronounced, changes at the protein levels. The results suggested that type XVI collagen expression is regulated by bFGF and TGF‐β in a manner similar to their regulation of the major type I fibrillar collagen produced by these cells.