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1.
Sci Rep ; 12(1): 1298, 2022 01 25.
Article in English | MEDLINE | ID: mdl-35079052

ABSTRACT

Road management practices, such as winter de-icing create ideal habitats and competitive advantage for salt-tolerant species. We aimed to map the occurrences of halophytes along roads in Hungary. Furthermore, we tested factors that might play a role in the roadside occurrences of five chosen native halophytes from rare to common, we encountered during our field surveys. These were Festuca pseudovina, Limonium gmelinii subsp. hungaricum, Podospermum canum, Puccinellia distans and Spergularia media. We found, that at least one halophyte species was documented in 71% of the total sampling points. Germination experiments indicated that substrate salt concentration significantly decreased germination rates in each of the five species, but in case of L. gmelinii subsp. hungaricum, or P. distans germination occurred on extremely high salt concentrations. Traffic intensity, the presence of other halophytes at the sampling point and the presence of a given species in the surrounding landscape had a significant positive effect on the occurrence of four of the five model species. Our results suggest that the studied species are mostly in the early stage of their roadside spread, colonizing roadsides close to their native distribution ranges. The possibility of a future range expansion along roads cannot be excluded.

2.
Rev Sci Instrum ; 84(4): 046106, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23635240

ABSTRACT

We report the design and construction of a cell that enables precisely controlled measurement of UV∕Vis spectra of thin films on transparent substrates at temperatures up to 800 K. The dimensions of the setup are accommodated by a standard Varian Cary 5E spectrophotometer allowing for widespread use in standard laboratory settings. The cell also fits in a Bio-Rad IR-spectrometer. The cell is constructed with an outer water cooled heat shield of aluminum and an inner sample holder with heating element, thermo-resistor and windows, made from nickel coated copper. The cell can operate both in air, and with an inert gas filling. We illustrate the utility of the cell by characterization of three commercially available near infrared absorbers that are commonly used for laser welding of plastics and are known to possess high thermal stability.

3.
Clin Exp Dermatol ; 35(3): 318-23, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20030666

ABSTRACT

BACKGROUND: Sensory neuropeptides such as neurokinin A or substance P modulate skin and immune cells the functions of neurokinin receptor activation during neurogenic inflammation. Zinc metalloproteases, such as neutral endopeptidase (NEP) and angiotensin-converting enzyme (ACE), effectively control the bioavailability of these neuropeptide mediators, which are released from sensory nerves, immune and skin cells during cutaneous responses to endogenous or exogenous noxious stimuli. Recently, studies have suggested that neuropeptides are one of the major pathogenetic fact in many dermatoses, such as allergic contact dermatitis (ACD), atopic dermatitis and psoriasis. AIM: To investigate the expression of major neuropeptides, SP and its degrading enzymes such as NEP and ACE, in the lesions of ACD. METHODS: A skin biopsy was obtained from 10 patients with ACD. We analysed the expression of these molecules by immunohistochemical staining, confocal laser scanning microscopy, western blotting and reverse transcription PCR. RESULTS: There was a significant increase in expression of SP in keratinocytes from ACD lesions compared with those in control skin. There was also increased expression of ACE but not NEP in ACD. CONCLUSION: Neuropeptides and their degrading enzymes, particularly SP and ACE, have a significant role in the pathogenesis of ACD.


Subject(s)
Dermatitis, Allergic Contact/enzymology , Neurokinin A/metabolism , Substance P/metabolism , Adult , Analysis of Variance , Case-Control Studies , Dermatitis, Allergic Contact/metabolism , Female , Humans , Immunoenzyme Techniques , Male , Neurokinin A/genetics , Neuropeptides/genetics , Neuropeptides/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Substance P/genetics , Young Adult
4.
Rev Sci Tech ; 27(3): 803-17, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19284048

ABSTRACT

This study evaluated the preparation of Shewhart's control charts using the concept of rational subgroups for monitoring the Salmonella antibody ELISA used for surveillance of Danish pig herds. Control charts were prepared for a buffer control sample, a negative serum sample and a positive serum sample. The quality control variables were the natural logarithm (In) of the uncalibrated optical density (OD) for the buffer control sample and the negative serum sample, and the calibrated OD (OD%) for the positive serum sample. Testing round (run) within laboratory robot was chosen as the subgroup, and separate control charts were prepared for five robots. The control limits were set at six times the standard deviation for In(OD) and three times the standard deviation for OD%. Evaluation based on a number of sensitising rules for control charts produced from historical data showed that use of the control charts could reveal systematic analytical errors.


Subject(s)
Antibodies, Bacterial/blood , Enzyme-Linked Immunosorbent Assay/veterinary , Salmonella Infections, Animal/diagnosis , Salmonella/immunology , Swine Diseases/diagnosis , Animals , Antibodies, Bacterial/analysis , Enzyme-Linked Immunosorbent Assay/methods , Enzyme-Linked Immunosorbent Assay/standards , Quality Control , Reference Standards , Reference Values , Salmonella Infections, Animal/epidemiology , Sensitivity and Specificity , Swine , Swine Diseases/epidemiology
5.
Article in English | MEDLINE | ID: mdl-16931186

ABSTRACT

We present fast, simple immunoturbidimetric assays suitable for direct determination of antibody 'concentration' and 'functionality' in crude samples, such as in-process samples taken at various stages during antibody purification. Both assays display excellent linearity and analytical recovery. Possible influences from commonly employed buffers and salts (present in samples at various concentrations), and of pH variations, were studied for both assays. Interference effects were shown to be negligible for the 'concentration' assay, such that sample pre-treatment prior to assay is unnecessary. The 'functionality' assay displayed concentration dependent sensitivity to interference for ammonium sulphate and Tris-(hydroxymethyl)-amino-methane, but was essentially unaffected by all other salts and buffer combinations tested. The immunoturbidimetric assays described here are generically applicable to polyclonal antibodies, require only basic laboratory equipment, are robust, fast, cheap, easy to perform, and readily adapted to automation.


Subject(s)
Antibodies, Monoclonal/isolation & purification , Antibody Specificity/immunology , Immunoassay/methods , Immunoglobulins/isolation & purification , Ammonium Sulfate/chemistry , Animals , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/immunology , Buffers , Humans , Hydrogen-Ion Concentration , Immunoglobulins/chemistry , Immunoglobulins/immunology , Rabbits , Reproducibility of Results
6.
Article in English | MEDLINE | ID: mdl-16931195

ABSTRACT

We have carried out a rigorous evaluation of eight commercially available packed bed chromatography adsorbents for direct capture and purification of immunoglobulins from clarified rabbit antiserum. Three of these materials featured rProtein A (rProtein A Sepharose Fast Flow, Mabselect, Prosep rProtein A) as the affinity ligand, and differed from one another primarily with respect to the underlying base matrix. The remaining five matrices comprised various synthetic low molecular weight ligands immobilised on hydrophilic porous supports and these included: MEP HyperCel, MabSorbent A1P, MabSorbent A2P, FastMabsA and Kaptiv-GY. The general experimental approach taken was to sequentially challenge packed beds of each matrix with a series of different strengths of a clarified antiserum; beginning with the weakest and ending with the strongest. Marked differences in performance (principally evaluated on the basis of dynamic binding capacity, recovery, and purity) were obtained, which allowed clear recommendations concerning the choice of adsorbents best suited for antibody capture from rabbit antisera, to be made.


Subject(s)
Antibodies, Monoclonal/isolation & purification , Chromatography/methods , Immune Sera/chemistry , Adsorption , Animals , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/immunology , Chromatography/instrumentation , Chromatography, Affinity/methods , Electrophoresis, Polyacrylamide Gel , Immune Sera/immunology , Immunoglobulins/chemistry , Immunoglobulins/isolation & purification , Ligands , Porosity , Protein Binding , Rabbits
8.
Exp Appl Acarol ; 33(1-2): 81-91, 2004.
Article in English | MEDLINE | ID: mdl-15285140

ABSTRACT

Brimer et al. (Vet. Parasitol. 51: 123-135, 1993 and 59: 249-255, 1995) developed a migration assay for acaricidal effect of acetylcholinesterase inhibitors and macrocyclic lactones utilising Sarcoptes scabiei var. suis mites. In contrast to many others, this assay is fully quantitative but quite time-consuming. The aim of the present investigation was to modify this assay to become faster and simpler. As a result accurate determinations can now be obtained within 6h, as opposed to 24h. Furthermore it was demonstrated that also Otodectes cynotis mites can be used with only minor modifications of the procedures. The cholinesterase inhibitor diazinon and the formamide amitraz were used as acaricides. Thus, the mite migration assay now has been proven useful for acaricidal compounds belonging to three chemical groups with different modes of action, namely organophosphorous cholinesterase inhibitors, macrocyclic lactones acting on the glutamanergic/GABAegic motoneurons, and formamide inhibitors of the octopamine systems of arthropods.


Subject(s)
Diazinon , Insecticides , Sarcoptes scabiei , Toluidines , Animals , Biological Assay , Cats , Chromatography, Gas , Linear Models , Movement/drug effects , Swine
9.
Int J Obes Relat Metab Disord ; 28(1): 99-104, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14610530

ABSTRACT

OBJECTIVE: To examine long-term effects of leisure time physical activity (ltpa) and occupational physical activity (opa) on later obesity, and to examine the effect of body weight on later physical inactivity in men with and without juvenile onset obesity. DESIGN: Population-based longitudinal study of obese and nonobese men, who were identified as draftees of median age of 19 y in 1943-77 and later examined at general health surveys in 1982-84, and in 1991-93. SETTING: Copenhagen and adjacent regions, Denmark. PARTICIPANTS: In all, 1143 juvenile obese men with a BMI > or =31 kg/m2 (corresponding to 35% overweight by an originally used national standard) at draft board examination, and, as a nonobese control group, 1278 men selected as a 0.5% random sample of the approximately 255,600 men examined at the draft board and thus representing the study population. MAIN OUTCOME MEASURES: Obesity, defined as BMI > or =30 kg/m2, and physical inactivity at the last survey. RESULTS: In the cross-sectional analyses, there were strong concurrent inverse associations between ltpa and prevalence of obesity in both groups, whereas there was no relation to opa. In logistic regression analyses of obesity at the last survey, including both ltpa and opa as well as age, BMI at draft board examination, BMI at first follow-up, length of education, smoking and drinking habits, there were no significant effects of ltpa and opa on the risk of development of obesity in the nonobese group or maintenance of obesity in the obese group. Similar analyses of physical inactivity at the last follow-up as outcome showed a significant direct effect of BMI at first follow-up, with a significant trend in the nonobese group, but not in the obese group and no effects on opa. CONCLUSION: There is no long-term influence of physical activity on development and maintenance of obesity in men, whereas greater body weight increases risk of later physical inactivity during leisure time.


Subject(s)
Exercise/physiology , Obesity/etiology , Adult , Aged , Body Mass Index , Follow-Up Studies , Humans , Leisure Activities , Longitudinal Studies , Male , Middle Aged , Occupations , Risk Factors
10.
Vet Rec ; 151(17): 502-5, 2002 Oct 26.
Article in English | MEDLINE | ID: mdl-12430998

ABSTRACT

The efficacy of a new Haemophilus parasuis vaccine for pigs was investigated. The vaccine contains H parasuis serotype 5 cells and is adjuvanted with Diluvac Forte (Intervet). Groups of pigs were vaccinated at five and seven weeks with 2 ml and their littermates served as unvaccinated controls. The vaccinated pigs were protected against a challenge with another strain of Hparasuis serotype 5 at two, eight and 17 weeks after the second vaccination, whereas the controls became very ill. The susceptibility of the pigs to the infection decreased with increasing age. After a heterologous challenge with H parasuis serotypes 1, 12, 13 and 14, two weeks after the second vaccination, the vaccine also gave clear protection. The severity of the illness among the control pigs differed with the different serotypes.


Subject(s)
Haemophilus Infections/veterinary , Haemophilus Vaccines , Haemophilus/immunology , Serositis/veterinary , Swine Diseases/prevention & control , Adjuvants, Immunologic/administration & dosage , Animals , Haemophilus/classification , Haemophilus/pathogenicity , Haemophilus Infections/microbiology , Haemophilus Infections/pathology , Haemophilus Infections/prevention & control , Random Allocation , Serositis/microbiology , Serositis/prevention & control , Serotyping/veterinary , Severity of Illness Index , Swine , Swine Diseases/microbiology , Swine Diseases/pathology , Treatment Outcome , Vaccines, Inactivated
11.
Acta Crystallogr B ; 58(Pt 4): 627-31, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12149552

ABSTRACT

In our earlier neutron diffraction study of the title compound at 30 K and 295 K an unconventional strategy in the refinement of hydrogen was applied and the same procedure has now been followed in the present investigation at 170 K and 90 K. There are two short O...H...O hydrogen bonds [2.437 (2) A and 2.442 (2) A at 30 K] and the 'heavy-atom' structure is centrosymmetric (P1) with centres of symmetry in the middle of the O...O bonds. However, statistical significance tests clearly show that an asymmetric location of both H atoms gives the most satisfactory description of the structure at all temperatures. The shift of hydrogen from the centre of symmetry is 0.15, 0.14, 0.15 and 0.15 A for H2 at 30, 90, 170 and 295 K, respectively, and 0.15, 0.15, 0.15 and 0.12 A for H4 (sigma = 0.01 A). Furthermore, the behaviour of H2 is very interesting: at 295 K and 170 K it is located on one side of the symmetry centre but at 90 K and 30 K it is located on the other side. A detailed determination of the unit-cell parameters by X-ray diffraction in the whole temperature range from 30 K to 295 K has revealed that the data points of the cell parameters as a function of temperature fall on two different straight lines with a sudden change in the slope around 135 K. It appears likely that the change in the location of H2 as the temperature is lowered is related to this behaviour. At 170 K, R(F) = 0.029 for 1236 reflections; at 90 K, R(F) = 0.030 for 1457 reflections.

12.
Article in English | MEDLINE | ID: mdl-12121040

ABSTRACT

A recently developed porcine model for aerogenous infection with Streptococcus suis serotype 2 was applied in a study of the phases of bacterial colonization and initial invasion. Eighteen pigs were exposed to aerosolized S. suis serotype 2 after pre-exposure to mild acetic acid in aerosol. The animals were killed consecutively within the first six days after challenge. After death, all animals were necropsied and examined by bacteriology, histopathology, and immunohistochemistry. Systemic infection was established in four out of 18 animals exposed to S. suis serotype 2. All systemically infected animals developed clinical signs and lesions typical of the infection. In four additional animals, subclinical infection was demonstrated by re-isolation of S. suis from the palatine tonsil. However, in all 18 challenged animals, immunohistochemistry demonstrated S. suis serotype 2 antigen in the palatine and/or nasopharyngeal tonsils. In all four systemically infected animals, S. suis serotype 2 antigen was also found in the mandibular lymph node. These observations point towards the tonsils as possible portals of entry for S. suis serotype 2 with subsequent lymphogenous spread. Thus, the present findings parallel the proposed pathogenesis for S. suis serotype 1 infection in pigs.


Subject(s)
Streptococcal Infections/veterinary , Streptococcus suis/pathogenicity , Swine Diseases/microbiology , Aerosols , Animals , Immunohistochemistry/veterinary , Male , Palatine Tonsil/immunology , Palatine Tonsil/microbiology , Streptococcal Infections/microbiology , Streptococcal Infections/pathology , Swine , Swine Diseases/pathology
13.
J Clin Neurosci ; 8(3): 286-7, 2001 May.
Article in English | MEDLINE | ID: mdl-11386811

ABSTRACT

Muscle-specific phosphorylase b kinase deficiency is an unusual form of glycogen storage disorder. The majority of patients are male with an age at diagnosis between 15 to 36 years. Clinical features include exercise intolerance, myalgia and muscle weakness. A forearm ischaemic exercise test is usually normal and histochemical staining for myophosphorylase positive. The demonstration of reduced muscle phosphorylase b kinase activity by biochemical assay confirms the diagnosis. We report a 36 year old male with phosphorylase b kinase deficiency and symptom onset in adult life.


Subject(s)
Exercise Tolerance , Glycogen Storage Disease Type V/diagnosis , Glycogen Storage Disease Type V/metabolism , Phosphorylase Kinase/deficiency , Adult , Age of Onset , Humans , Male
14.
J Biol Chem ; 276(31): 29195-9, 2001 Aug 03.
Article in English | MEDLINE | ID: mdl-11389142

ABSTRACT

Factor VII requires the cleavage of an internal peptide bond and the association with tissue factor (TF) to attain its fully active factor VIIa (FVIIa) conformation. The former event alone leaves FVIIa in a zymogen-like state of relatively low specific activity. We have designed a number of FVIIa mutants with the aim of mimicking the effect of TF, that is, creating molecules with increased intrinsic (TF-independent) enzymatic activity. Based on a possible structural difference between free and TF-bound FVIIa (Pike, A. C. W., Brzozowski, A. M., Roberts, S. M., Olsen, O. H., and Persson, E. (1999) Proc. Natl. Acad. Sci. U. S. A. 96, 8925--8930), we focused on the helical region encompassing residues 307-312 and residues in its spatial vicinity. For instance, FVIIa contains Phe-374 and Leu-305, whereas a Phe/Tyr residue in the position corresponding to 374 in homologous coagulation serine proteases is accompanied by Val in the position corresponding to 305. This conceivably results in a unique orientation of this helix in FVIIa. Substitution of Val for Leu-305 in FVIIa resulted in a 3--4-fold increase in the intrinsic amidolytic and proteolytic activity as compared with wild-type FVIIa, whereas the activity in complex with soluble TF remained the same. In accordance with this, L305V-FVIIa exhibited an increased rate of inhibition as compared with wild-type FVIIa, both by d-Phe-Phe-Arg-chloromethyl ketone and antithrombin III in the presence of heparin. The increased FVIIa activity upon replacement of Leu-305 by Val may be mediated by a movement of the 307--312 helix into an orientation resembling that found in factors IXa and Xa and thrombin. The corresponding shortening of the side chain of residue 374 (Phe --> Pro) had a smaller effect (about 1.5-fold increase) on the intrinsic activity of FVIIa. Attempts to increase FVIIa activity by introducing single or multiple mutations at positions 306, 309, and 312 to stabilize the 307-312 helix failed.


Subject(s)
Factor VIIa/chemistry , Factor VIIa/metabolism , Leucine , Valine , Amino Acid Substitution , Blood Coagulation , Factor VIIa/genetics , Genetic Variation , Humans , Kinetics , Models, Molecular , Mutagenesis, Site-Directed , Protein Structure, Secondary , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism
15.
Acta Crystallogr B ; 57(Pt 3): 311-6, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11373389

ABSTRACT

The structure of the title compound has been studied by neutron diffraction at 30 and 295 K, with the emphasis on the location of the protons. There are two crystallographically independent H atoms in two very short hydrogen bonds, 2.437 (2) and 2.442 (2) A at 30 K. The structure could be refined successfully in the centrosymmetric space group P1;, with the H atoms located at the centres of symmetry. However, the form of the thermal ellipsoids of hydrogen indicated either asymmetric hydrogen bonds or overlap of two closely spaced, partially occupied positions around the centres of symmetry. Several different types of refinements have then been applied, including unconventional models; with all atoms except hydrogen constrained in P1;, but with hydrogen allowed to refine without any constraints in P1, anisotropic refinement of all atoms resulted in clearly off-centred hydrogen positions. Significance tests clearly showed that the results from this constrained refinement give the most satisfactory description of the structure. This structure may be described as 'pseudo-centrosymmetric with non-centred protons'. The results demonstrate that it is very important to also include refinement models with non-centrosymmetric hydrogen in a centrosymmetric environment when studying very short hydrogen bonds. The shifts of the two H atoms from the centres of symmetry are 0.15 (1) and 0.12 (1) A, respectively, at 30 K, and 0.15 (1) A for both H atoms at room temperature. At 30 K: R(F) = 0.036 for 1485 reflections; at 295 K: R(F) = 0.035 for 1349 reflections.

16.
Cell ; 103(6): 853-64, 2000 Dec 08.
Article in English | MEDLINE | ID: mdl-11136971

ABSTRACT

POU domain proteins contain a bipartite DNA binding domain divided by a flexible linker that enables them to adopt various monomer configurations on DNA. The versatility of POU protein operation is additionally conferred at the dimerization level. The POU dimer formed on the PORE (ATTTGAAATGCAAAT) can recruit the transcriptional coactivator OBF-1, whereas POU dimers formed on the consensus MORE (ATGCATATGCAT) or on MOREs from immunoglobulin heavy chain promoters (AT[G/A][C/A]ATATGCAA) fail to interact. An interaction with OBF-1 is precluded since the same Oct-1 residues that form the MORE dimerization interface are also used for OBF-1/Oct-1 interactions on the PORE. Our findings provide a paradigm of how specific POU dimer assemblies can differentially recruit a coregulatory activity with distinct transcriptional readouts.


Subject(s)
DNA-Binding Proteins/metabolism , Oligonucleotides/metabolism , Trans-Activators/metabolism , Transcription Factors/metabolism , Amino Acid Motifs , Animals , Base Sequence , Cell Line , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/genetics , Dimerization , Gene Expression Regulation , Genes, Reporter , Host Cell Factor C1 , Humans , Mice , Models, Molecular , Molecular Sequence Data , Octamer Transcription Factor-1 , Octamer Transcription Factor-2 , Octamer Transcription Factor-3 , Octamer Transcription Factor-6 , Oligonucleotides/genetics , Promoter Regions, Genetic , Protein Binding/genetics , Protein Structure, Tertiary , Sequence Analysis , Trans-Activators/genetics , Transcription Factor Pit-1 , Transcription Factors/chemistry , Transcription Factors/genetics , Transcription, Genetic , Transfection
17.
Acta Crystallogr B ; 55(Pt 6): 830-840, 1999 Dec 01.
Article in English | MEDLINE | ID: mdl-10927424

ABSTRACT

The charge distribution has been determined by multipole refinements against single-crystal X-ray diffraction data. In the refinements a comparison was made between the densities based on H-atom parameters from X-ray and neutron data, respectively. X-ray study: lambda(Mo Kalpha) = 0.71073 Å, F(000) = 408; at 30 K: R(F) = 0.015 for 6686 reflections; at 295 K: R(F) = 0.022 for 4630 reflections. The nickel ion is octahedrally surrounded by four water molecules and two chloride ions, forming a locally neutral Ni(H(2)O)(4)Cl(2) complex. Two of the water molecules are coordinated to nickel approximately in one of the tetrahedral ('lone-pair') directions; the other two are trigonally coordinated. At 30 K one H atom in one of the trigonally coordinated water molecules is disordered, with equal occupation of two different positions. Owing to the polarizing influence of the nickel ion there are two peaks in the lone-pair plane of the water molecules when these are tetrahedrally coordinated; for those trigonally coordinated there is just one peak. The individual ('partial') charge densities, calculated from the deformation functions of only nickel or the separate water molecules, have also been calculated to study the effects of superposition of the individual densities. In the individual density of nickel an excess is observed in the diagonal directions and a deficiency in the ligand directions. However, owing to the influence of the whole crystalline environment, the maxima around nickel are not found in the planes defined by nickel and the six ligands.

18.
Eur J Biochem ; 198(1): 1-6, 1991 May 23.
Article in English | MEDLINE | ID: mdl-2040270

ABSTRACT

The primary structure of an extracellular ribonuclease (RNase LE) from Pi-depleted media of cultured cells of Lycopersicon esculentum L. cv. Lukullus has been determined. This was carried out by analysis of peptides isolated after enzymatic and chemical cleavage of the reduced and S-ethylpyridylated protein. RNase LE consists of 205 amino acid residues and has a molecular mass of 22,666 Da and an isoelectric point of 4.24. The enzyme contains 10 half-cystines. There are no potential N-glycosylation sites in the sequence. The sequence of RNase LE is homologous with those of self-incompatibility proteins of several higher plant species and with those of a number of fungal RNases. The sequence similarity with the family of self-incompatibility proteins is greater than with the fungal RNases, suggesting that the self-incompatibility proteins arose from ancestral RNase by gene duplication after the divergence of higher plants and fungi. Two pentapeptide sequences, i.e. HGLWP and KHGTC (or KHGSC), are present at identical positions in all the aligned proteins, suggesting that they contribute to the active site.


Subject(s)
Endoribonucleases/genetics , Phosphates/pharmacology , Vegetables/enzymology , Amino Acid Sequence , Cells, Cultured , Endoribonucleases/biosynthesis , Enzyme Induction , Hydrolysis , Molecular Sequence Data , Sequence Alignment , Trypsin
19.
Czas Stomatol ; 43(9): 567-72, 1990 Sep.
Article in Polish | MEDLINE | ID: mdl-2104392

ABSTRACT

The condition of the parodontium was studied in 281 children. Group I comprised children with malocclusion treated by maxillary orthopaedic methods, group II--children with non-treated malocclusion, group III--children with normal occlusion. The condition of the parodontium was assessed in various types of malocclusion, in groups of teeth and in relation to the duration of treatment with maxillary-orthopaedic devices. The parodontium was evaluated using the indices GI and PMA. The highest prevalence of parodontitis was found in cases of isolated crowding of teeth. Changes were observed, most frequently, at the lower incisors. With time of device use the values of the GI and PMA indices increased to a peak value in the 2nd year of the treatment, while past that time these values fell.


Subject(s)
Orthodontic Appliances/adverse effects , Periodontal Diseases/etiology , Child , Humans , Malocclusion/therapy , Orthodontics, Corrective
20.
J Mol Biol ; 207(4): 829-32, 1989 Jun 20.
Article in English | MEDLINE | ID: mdl-2760932

ABSTRACT

A high precision, two-dimensional study of oxygen and carbon monoxide binding to Panulirus interruptus hemocyanin has been carried out. Global data analysis of three types of experiments, probing the molecule in its various states of CO and O2 ligation, revealed the entire hexamer to be the basic allosteric unit involved in a two-state mechanism. The co-operativity and linkage of the two ligands are presented in terms of derivative Hill plot surfaces extended along co-ordinates of CO and O2 activities giving a detailed and comprehensive view of the binding behavior. Among the findings is an apparent high co-operativity of carbon monoxide binding at high oxygen activity. The results are discussed in view of a general mechanism for co-operative behavior found in larger hemocyanin aggregates concerning "nested" allosteric interactions.


Subject(s)
Carbon Monoxide/metabolism , Hemocyanins/metabolism , Nephropidae/metabolism , Oxygen/metabolism , Animals , Ligands , Models, Biological
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