Natural compounds in the human diet and their ability to bind mutagens prevents DNA-mutagen intercalation

Human diet may contain many mutagenic or carcinogenic aromatic compounds as well as some beneficial physiologically active dietary components, especially plant food phytochemicals, which act as mutagenesis or carcinogenesis inhibitors. This study compared the binding properties of natural compounds in the human diet (caffeine, theophylline, theobromine, and resveratrol) with a water-soluble derivative of chlorophyll to bind to acridine orange, a known mutagen. An analysis was conducted to determine which substances were effective binding agents and may thus be useful in prevention of chemical-induced mutagenesis and carcinogenesis. Data indicated that in order to bind 50% of the mutagen in a complex, less than twice the concentration of chlorophyllin was needed, the resveratrol concentration was 20-fold higher, while a 1000-fold or even 10,000-fold excess of xanthines were required to bind acridine orange.

Determination of lead, cadmium, and persistent organic pollutants in wild and orchard-farm-grown fruit in northeastern Poland

The concentrations of the heavy metals lead (Pb) and cadmium (Cd) were determined in berries (blackberry, raspberry, bilberry, wild strawberry), and hazelnuts picked from plants in the wild as well as in fruit (blackberry, raspberry, blueberry) and hazelnuts picked from orchard-farmed plants in northeastern Poland. The levels of seven congeners of polychlorinated biphenyls (PCB(7)), gamma isomer of hexachlorocyclohexane (gamma-HCH), and sum of dichlorodiphenyl trichloroethane and its metabolites (SigmaDDT) were also measured in plants and nuts. In addition, the concentrations of Pb, Cd, PCB(7,) gamma-HCH, and SigmaDDT were determined in the surface samples of soil from the sites of fruit picking. The highest acceptable concentrations based upon Polish standards for Pb and Cd were not exceeded in forest fruit. In wild berries, Pb occurred at a level below the detection limit, whereas the concentration of Cd ranged from 6 to 49 microg/kg fresh weight. The levels were Cd 72 microg/kg fresh weight and Pb 290 microg/kg fresh weight in raspberries from orchard plants and exceeded the maximal acceptable limit of 50 microg/kg for Cd and 200 microg/kg for Pb. The level of Pb at 210 microg/kg fresh weight in hazelnuts from orchard plants also exceeded maximal acceptable limits. Individual samples of fruit, regardless of their origin, were found to contain trace amounts of organic pollutants such as 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (p,p'-DDE) and PCB congeners 101 and 118. All soil samples contained from 3.2 to 14.9 mg/kg dry weight concentrations of Pb and most soil samples also contained Cd. Further, individual soil samples were found to contain high levels of SigmaDDT (145 microg/kg), including p,p'-DDT at a concentration of 67 microg/kg. The concentrations of persistent organic pollutants (POP) in wild and orchard-farm-grown fruit in northeastern Poland were generally below threshold permissible limits, and no correlation was found between levels of contaminants in soils and POP concentrations in fruit.

The oxidation status of ALDH3A1 in human saliva and its correlation with antioxidant capacity measured by ORAC method

Oxidation status of the salivary aldehyde dehydrogenase (ALDH) was measured in healthy human population using two-assay fluorimetric method and compared with antioxidant capacity (ORAC) in non-smoking and heavy smokers group. Influence of high or low antioxidant diet was also examined. Except for the group of smokers, the salivary ALDH oxidation degree in human saliva was not correlated with antioxidant capacity. Simultaneously direct administration of the antioxidant-containing drug, Fluimucil, resulted in short-term, but statistically significant increase of the reduced (active) form of the enzyme, presumably due to a radical-scavenging activity of the drug.

Salivary aldehyde dehydrogenase: activity towards aromatic aldehydes and comparison with recombinant ALDH3A1

A series of aromatic aldehydes was examined as substrates for salivary aldehyde dehydrogenase (sALDH) and the recombinant ALDH3A1. Para-substituted benzaldehydes, cinnamic aldehyde and 2-naphthaldehydes were found to be excellent substrates, and kinetic parameters for both salivary and recombinant ALDH were nearly identical. It was demonstrated that for the fluorogenic naphthaldehydes the only produced reaction product after incubation in saliva is the carboxylate.

Kinetics of C. elegans DcpS cap hydrolysis studied by fluorescence spectroscopy

DcpS (scavenger decapping enzyme) from nematode C. elegans readily hydrolyzes both monomethyl- and trimethylguanosine cap analogues. The reaction was followed fluorimetrically. The marked increase of fluorescence intensity after the cleavage of pyrophosphate bond in dinucleotides was used to determine K(m) and V(max)values. Kinetic parameters were similar for both classes of substrates and only slightly dependent on pH. The hydrolysis was strongly inhibited by methylene cap analogues (m(7)Gp(CH(2))ppG and m(7)Gpp(CH(2))pG) and less potently by ARCA (m(7,3' O)GpppG).

Salivary aldehyde dehydrogenase--reversible oxidation of the enzyme and its inhibition by caffeine, investigated using fluorimetric method

OBJECTIVE

We have applied fluorimetric method to monitor aldehyde dehydrogenase (ALDH*) activity in human saliva samples to study inactivation, reactivation and inhibition of the enzyme.

DESIGN

Saliva samples were collected to buffer stock solution, containing various thiols, and assayed in the presence of the fluorogenic substrate 6-dimethylamino-2-naphthaldehyde and NAD(+). Fluorescence of the produced 6-dimethylamino-2-naphthalene carboxylate was used to measure the reaction rate.

RESULTS

Kinetic parameters for the highly fluorogenic substrate, 6-dimethylamino-2-naphthaldehyde were measured, with apparent K(m) of 7.9 microM at pH 7.3. The apparent K(m) for NAD(+) was 1.2 microM. The observed ALDH activity is unstable in the absence of thiols, but can be stabilized by 1mM glutathione, and inactivated enzyme can be re-activated within 10 min by treatment of 0.5 mM DTT. Two-assay procedure was applied to measure degree of inactivation of ALDH in saliva samples. It was found that degree of ALDH inactivation in fresh samples, stabilized by glutathione, is between 0% and 90%, with average value ca. 40%. Caffeine and theophylline were shown to be moderate inhibitors of salivary ALDH.

CONCLUSIONS

Oxidation of the salivary ALDH in fresh saliva may be reliably measured using fluorimetric two-assay procedure. Preliminary statistics indicate that in most individuals this enzyme is partially inactive. Inhibition of the salivary ALDH by caffeine may have consequences for nutrition safety.

The "interceptor" properties of chlorophyllin measured within the three-component system: intercalator-DNA-chlorophyllin

In aqueous solutions, in the presence of double-stranded DNA, chlorophyllin (CHL) forms complexes with each of the three DNA intercalators: acridine orange (AO), quinacrine mustard (QM), and doxorubicin (DOX). The evidence for these interactions was obtained by measurement changes in the absorption and fluorescence spectra of the mixtures containing DNA and intercalators during titration with CHL. A model of simple competition between DNA and CHL for the intercalator was used to define the measured interactions. The concentrations of the complexes estimated based on this model were consistent with the concentrations obtained by actual measurement of the absorption spectra. The present data provide further support for the role of chlorophyllin as an "interceptor" that may neutralize biological activity of aromatic compounds including mutagens and antitumor drugs.

Interaction of three Caenorhabditis elegans isoforms of translation initiation factor eIF4E with mono- and trimethylated mRNA 5' cap analogues

Translation initiation factor eIF4E binds the m(7)G cap of eukaryotic mRNAs and mediates recruitment of mRNA to the ribosome during cap-dependent translation initiation. This event is the rate-limiting step of translation and a major target for translational control. In the nematode Caenorhabditis elegans, about 70% of genes express mRNAs with an unusual cap structure containing m(3)(2,2,7)G, which is poorly recognized by mammalian eIF4E. C. elegans expresses five isoforms of eIF4E (IFE-1, IFE-2, etc.). Three of these (IFE-3, IFE-4 and IFE-5) were investigated by means of spectroscopy and structural modelling based on mouse eIF4E bound to m(7)GDP. Intrinsic fluorescence quenching of Trp residues in the IFEs by iodide ions indicated structural differences between the apo and m(7)G cap bound proteins. Fluorescence quenching by selected cap analogues showed that only IFE-5 forms specific complexes with both m(7)G- and m(3)(2,2,7)G-containing caps (K(as) 2 x 10(6) M(-1) to 7 x 10(6) M(-1)) whereas IFE-3 and IFE-4 discriminated strongly in favor of m(7)G-containing caps. These spectroscopic results quantitatively confirm earlier qualitative data derived from affinity chromatography. The dependence of K(as) on pH indicated optimal cap binding of IFE-3, IFE-4 and IFE-5 at pH 7.2, lower by 0.4 pH units than that of eIF4E from human erythrocytes. These results provide insight into the molecular mechanism of recognition of structurally different caps by the highly homologous IFEs.

Interactions of chlorophyllin with acridine orange, quinacrine mustard and doxorubicin analyzed by light absorption and fluorescence spectroscopy

The present study was designed to estimate the ability of chlorophyllin (CHL) to interact with two acridine mutagens, quinacrine mustard (QM) and acridine orange (AO), and with the antitumor anthracycline doxorubicin (Dox). To this end, aqueous solutions of QM, AO or Dox during titration with CHL were subjected to spectrophotometry and spectrofluorimetry to detect possible interactions between these reagents. The data indicate that CHL forms complexes with AO, QM or Dox in these solutions. The presence of the complexes was manifested by a bathochromic shift of the absorption spectra, as well as by strong quenching of the fluorescence of each of these mutagens in the presence of CHL. CHL, thus, may serve as an interceptor of these mutagenic acridines in different in vivo or in vitro applications. Its ability to interact with Dox may potentially be utilized to detoxify patients overdosed with this or similar drugs.

Interaction of three Caenorhabditis elegans isoforms of translation initiation factor eIF4E with mono- and trimethylated mRNA 5' cap analogues

Translation initiation factor eIF4E binds the m(7)G cap of eukaryotic mRNAs and mediates recruitment of mRNA to the ribosome during cap-dependent translation initiation. This event is the rate-limiting step of translation and a major target for translational control. In the nematode Caenorhabditis elegans, about 70% of genes express mRNAs with an unusual cap structure containing m(3)(2,2,7)G, which is poorly recognized by mammalian eIF4E. C. elegans expresses five isoforms of eIF4E (IFE-1, IFE-2, etc.). Three of these (IFE-3, IFE-4 and IFE-5) were investigated by means of spectroscopy and structural modelling based on mouse eIF4E bound to m(7)GDP. Intrinsic fluorescence quenching of Trp residues in the IFEs by iodide ions indicated structural differences between the apo and m(7)G cap bound proteins. Fluorescence quenching by selected cap analogues showed that only IFE-5 forms specific complexes with both m(7)G- and m(3)(2,2,7)G-containing caps (K(as) 2 x 10(6) M(-1) to 7 x 10(6) M(-1)) whereas IFE-3 and IFE-4 discriminated strongly in favor of m(7)G-containing caps. These spectroscopic results quantitatively confirm earlier qualitative data derived from affinity chromatography. The dependence of K(as) on pH indicated optimal cap binding of IFE-3, IFE-4 and IFE-5 at pH 7.2, lower by 0.4 pH units than that of eIF4E from human erythrocytes. These results provide insight into the molecular mechanism of recognition of structurally different caps by the highly homologous IFEs.

Neurodevelopmental rehabilitation according to Glenn Doman (the Philadelphia Neurodevelopment Method)

Neurodevelopmental rehabilitation methods for children with nonprogressive brain injury began to take shape in the late 1940s in the US and Europe. One of the most important centers continuously involved in promoting neurodevelopmental concepts is the Institute for the Achievement of Human Potential. The method of child neurodevelopment is based on the theory of neurological organization. In practice this global method seeks to provide the child's brain with ordered information suitable for his or her present level of development, with increasing duration, frequency, and intensity. As is the case with other rehabilitation methods, the theoretical foundations and clinical efficacy of these rehabilitation techniques have not yet been adequately documented, which has been pointed out by the numerous critics of these methods.

[Diagnostic value of sleep deprivation as the EEG activation method in diagnosis of epilepsy in developmental age]

The paper presented the significance of EEG activation in diagnosing epilepsy in children and adolescents. EEG records of 108 patients between 3-19 years of age with the occurrence of various types of paroxysmal disorders who were admitted to Chair and Department of Developmental Neurology University of Medical Sciences in Poznań were analysed. Standard EEG was administered to all children twice: the first examination at rest with hyperventilation (HV) and photostimulation (FS) and the second one after total or partial sleep deprivation (DS). At awaking state normal records were stated in 57% of cases, in 15% paroxysmal changes in HV or FS appeared, in the rest of cases (28%) generalised paroxysmal disorders, localised changes, lateralised or diffused were noted. Among EEG activation methods DS occurred to be the most effective after it, 52 patients (48%) were diagnosed for generalised paroxysmal changes, 20% for localised, 3% lateralised and for 6% for diffused changes. Normal EEG were recorded in 22% of examined children and adolescents. The epilepsy were diagnosed in 59 (55%) of patients mostly with generalised seizures (28) partial secondarily generalised (16) and partially complex (11). In 49 (45%) children were diagnosed with other paroxysmal disorders.

[Correlation between oncologically suspicious cytologic smears and colposcopic images of the uterine cervix and results of histopathologic examination taken from material provided by the Gynecology Department of the Pruszkow Municipal Hospital from 1995 to 1997]

The objective of the paper was an evaluation of relationship between oncologically suspicious cytologic smear and colposcopic images, and the results of histopathological examination of samples collected from the vaginal portion of uterine cervix and from cervical canal scrapings. The material consisted of 60 patients with cytologic group 3 and 13 patients with group 4 and 5 according to Papanicolaou, who had been selected during a two-year preventive examination period. Cytologic group 3 patients (group 1) were subjected to cytological assessment and colposcopic examination again in order to determine further diagnostic indications. Cytologic group 4 and 5 women (group 2) were collected samples from the vaginal portion of uterine cervix under colposcopic supervision, without waiting for the result of cytologic re-assessment. All these patients were also collected samples from the vaginal portion of uterine cervix. In patients of cytologic group 3 the cytologic and colposcopic examination results were found to be compatible with histopathologic examination results in 53.3% cases. In patients of cytologic group 4 or 5 this factor was established at 92.3%.

Culture of human nasal epithelial cells from nasal polyps on collagen matrix

Epithelial cell cultures became an experimental model employed for both animal and human studies. We established a modified method of culture of human nasal epithelial cells from nasal polyps using serum-free, hormonally supplemented Ham's F-12 medium and Vitrogen 100 collagen matrix. Cells reached confluent monolayer structures in 5 to 7 days (mean time 6 +/- 0.89 days) of culture. The confluent cultures consisted of pure epithelial cells, which was confirmed by light and electron microscopy, and immunohistochemical staining with anticytokeratin antibody. The success ratio of cultures was 61.5%. The culture system described is efficient enough to provide pure epithelial cells for further functional studies.

[A case of Potter syndrome in a male newborn infant]

The Potter syndrome was discussed based on the reference materials. The aim of the work is to present the course of pregnancy of 19-year-old nullipara ended by the delivery of male newborn with signs of above described syndrome.

Effect of rapid rigor mortis processes on protein functionality in pectoralis major muscle of domestic turkeys

The pale, soft, exudative (PSE) phenomenon in turkey pectoralis major (breast) muscle was studied using a combination of biochemical, meat quality, microscopic, and gel electrophoresis techniques. Breast muscle samples were collected from turkeys characterized by slow vs fast postmortem glycolysis assessed by muscle pH at 20 min after death. The PSE group was characterized by lower muscle ATP (P < .05) and higher lactate levels (P < .05) compared with the normal group. Excess water-holding capacity and cooking yield were significantly lower (P < .05) in the PSE group than in normal turkeys. Breast muscle of the PSE group was also lighter (P < .05) than that in the normal group as determined by Minolta L* values. The SDS-PAGE, Western blotting, and immunofluorescence microscopy revealed that phosphorylase, a soluble enzyme, became tightly associated with the myofibrils in muscle from the PSE group. Also, less myosin could be solubilized from PSE vs normal myofibril samples. The results indicate that irreversible myosin insolubility due to low pH and high-temperature conditions is decisive in the development of PSE turkey breast muscle.

Medical emergencies in commercial air travel

There are physiologic and logistic concerns involved in caring for patients with inflight emergencies. This article presents the physiologic changes that occur at altitude, the types of medical problems that can be encountered, and management strategies. An overview is also presented of the medical training of flight attendants and the medical equipment that is available on commercial aircraft.

Isolation and characterization of a cDNA from flowers of Cynara cardunculus encoding cyprosin (an aspartic proteinase) and its use to study the organ-specific expression of cyprosin

Poly(A)+ RNA isolated from flower buds of Cynara cardunculus has been used to prepare a cDNA library. Screening of the cDNA after expression of cloned DNA with antibodies raised against the large subunit of cyprosin 3 resulted in the isolation of six positive clones. One of these clones (cypro1s; a 1.7 kb Eco RI fragment) codes for cyprosin. The nucleotide sequence contain a 1419 bp open reading frame coding for 473 amino acids (aa) including a putative full-length mature protein (440 aa) and a partial prosequence (33 aa). Cypro1s contains a 162 bp 3' non-coding region followed by a poly(A) tail. The deduced amino acid sequence shows high homology to other plant aspartic proteinases. The homology to mammalian and microbial aspartic proteinases is somewhat lower. Plant aspartic proteinases contain an insert of around 100 aa. We are modelling where this plant-specific insert will appear in the structure of cyprosin. Using cypro1s as a probe in northern blot analysis, the expression of cyprosin in developing flowers and other tissues has been studied. The signal on the northern blot increased for RNA samples from early (flower buds 6 mm in length) to later stages of floral development (flower buds up to 40 mm in length). In late stages of floral development (open flowers 50 mm in length and styles from such flowers) no hybridization signal was visualized showing that the synthesis of mRNA encoding the cyprosin starts in early stages of floral development and switches off at maturation of the flower.(ABSTRACT TRUNCATED AT 250 WORDS)

Mutation analysis of the C-terminal vacuolar targeting peptide of tobacco chitinase: low specificity of the sorting system, and gradual transition between intracellular retention and secretion into the extracellular space

The C-terminal propeptide of tobacco (Nicotiana tabacum) chitinase A has been shown to be necessary and sufficient for targeting of chitinases to the plant vacuole. The sequence specificity of this vacuolar targeting peptide (VTP) has now been analysed using transient expression of chitinases in Nicotiana plumbaginifolia protoplasts. An extracellular cucumber chitinase, previously used as a secreted reporter protein in transgenic tobacco, was also secreted into the incubation medium by the transiently transformed protoplasts. Addition of six to seven amino acids at the C-terminus to generate the VTP of tobacco chitinase A were sufficient to cause retention of most of the cucumber chitinase within the protoplasts. The chitinase A itself, as well as a mutant lacking the N-terminal chitin-binding domain, were retained to 80% in the protoplasts when low concentrations of the plasmid were used in the transient expression system. At high concentrations of plasmid, causing high levels of transiently expressed chitinase, retention was reduced, indicating saturation of the sorting system. Deletion of the C-terminal methionine did not affect the intracellular location, but deletion of even a single internal amino acid of the VTP caused predominantly secretion of tobacco chitinase A. In contrast, exchanges of amino acids in the VTP as well as substitution of the VTP with random sequences had intermediary effects that covered the whole range from retention to secretion. The results suggest that the sorting system responsible for the diversion of secretory proteins to the vacuole has a low specificity for the sequence of C-terminal targeting peptides, and that sequence changes in the VTP allow a gradual transition from vacuolar retention to secretion.

Prehospital care and the military

Significant evolution has occurred in prehospital care over the past decade. Civilian emergency medical service (EMS) systems have become progressively sophisticated. Military systems have tended to maintain a wartime philosophy toward prehospital care, and thus its peacetime ambulance service, at times, is not prepared to provide the same standard of care given by the civilian community. This article reviews the current status of civilian and military EMS and attempts to put in perspective the directions that the military could go to improve on the prehospital care it provides.