[On quality of life after surgical therapy of oral cancer - a retrospective multi-center study: the connection between dedentition, denture, quality of life, and dysphagia, and the resulting rehabilitation schemes]

PURPOSE

The surgical treatment of oral cancer results in functional and aesthetical impairments. Patients' quality of life is considerably impaired by oral symptoms resulting from therapy of oral cancer. In many cases the inevitable resection of the tumor, as well as the adjuvant radiochemotherapy will cause the destruction of physiologically and anatomically important structures. One focus of research was the specific rehabilitation of dental loss by functional dentures. Another was the course of 19 impairments (comprehension of speech for unknown others, comprehension of speech for familiar others, eating/swallowing, mobility of the tongue, opening range of the mouth, mobility of lower jaw, mobility of neck, mobility of arms and shoulders, sense of taste, sense of smell, appearance, strength, appetite, respiration, pain, swelling, xerostomia, halitosis).

METHODS

Commissioned by the German, Austrian and Swiss cooperative group on tumors of the maxillofacial region (DOSAK), data were collected in 3.894 questionnaires at 43 hospitals in Germany, Austria and Switzerland. The catalogue comprised 147 items in 9 chapters. At the end of the enquiry, 1.761 anonymous questionnaires were returned by 38 hospitals. 1.652 of these could be evaluated regarding the question.

RESULTS

The sum score of the 19 impairments was highly increased immediately after the operation and recovered over the next 6 months, without, however, reaching the pre-surgery level. Of 1.652 patients, only 35% did not lose any teeth during therapy. 23% lost up to 5, 17% up to 10 teeth. A quarter of the patients lost more than 10 teeth. The more teeth were lost, the greater the decline of quality of life (p < or = 0.001), although this could be allayed by the functionality of the dentures (p < or = 0.001). There is a reciprocal dependence between the functionality of dental prosthetics and impairment by eating/swallowing (p < or = 0.001).

CONCLUSIONS

Patients' quality of life after radical surgery of a carcinoma of the oral cavity depends not only on the functionality of dentures and the specificity of rehabilitation, but also from the initial findings, the extent and location of the resection, the chosen therapy, the general circumstances of the patient's life as well as their strategies of coping. These factors, however, unlike those of functionality of dental prosthesis and rehabilitation, are not modifiable.

[The impact of radiotherapy on quality of life -- a survey of 1411 patients with oral cancer]

PURPOSE

The therapy of patients with oral cancer often requires a combination of surgery and radiotherapy. This leads to trauma of healthy tissue. The impact of this side effect on quality of life was investigated. Additionally the impairment of 19 factors was determined (comprehension of speech for unknown others, comprehension of speech for familiar others, eating/swallowing, mobility of the tongue, opening range of the mouth, mobility of lower jaw, mobility of neck, mobility of arms and shoulders, sense of taste, sense of smell, appearance, strength, appetite, respiration, pain, swelling, xerostomia, halitosis).

METHODS

This retrospective multicenter study was conducted under the auspices of DOESAK (a German, Austrian and Swiss cooperative group on tumors of the maxillofacial region). The Bochum Questionnaire on Rehabilitation was used to determine 147 items. 3894 questionnaires where sent to 43 clinics in Germany, Austria and Switzerland. 1761 questionnaires where returned, while 1411 of them included all of the answers necessary for this study.

RESULTS

686 of 1411 patients where irradiated. Before the beginning of therapy the impairment of the 19 factors was not significantly higher in the group that later received radiotherapy. After therapy there is a significantly higher impairment of the irradiated patients. The factors that are especially worse are xerostomia, swallowing and understanding of speech. The quality of life was not significantly lower.

CONCLUSIONS

Although radiotherapy leads to trauma of healthy tissue this method is indicated as it has no significant impact on quality of life. During the rehabilitation physiotherapists should relieve the impairment of speech, eating and swallowing.

Transgenic Arabidopsis plants expressing Escherichia coli pyrophosphatase display both altered carbon partitioning in their source leaves and reduced photosynthetic activity

The effects of the cytosolic expression of Escherichia coli pyrophosphatase (ppa) were investigated in the rosette leaves of transgenic Arabidopsis plants. During the daytime, glucose and fructose were found to accumulate at levels that were approximately two- to threefold higher in these plants than in the wild type. Interestingly, however, neither sucrose nor starch levels showed any distinctive build up in transgenic plants except under continuous white light growth conditions, during which they accumulated at high levels. Additionally, the leaves of transgenic Arabidopsis plants contain two- to threefold higher levels of inorganic phosphate (Pi) and two- to sixfold higher levels of uridine diphosphate-glucose than wild type plants during the diurnal cycle. In contrast, triose phosphate contents in the leaves of E. coli ppa transformants were either similar or slightly decreased when compared with wild type leaves. Furthermore, the photosynthetic activity of these transgenic plants was found to be reduced by 20-40% compared to normal levels. These results indicate that induction of ppa activity in the cytosol affects carbon partitioning between source and sink organs and also that the concomitant increase in Pi caused the accumulation of carbon metabolites and reduced photosynthetic activity.

Use of Pi5(t) markers in marker-assisted selection to screen for cultivars with resistance to Magnaporthe grisea

Identification of the PCR markers tightly linked to genes that encode important agronomic traits is useful for marker-assisted selection (MAS). The rice Pi5(t) locus confers broad-spectrum resistance to Magnaporthe grisea, the causal agent of rice blast disease. It has been hypothesized that the Pi5(t) locus carries the same gene as that encoded by the Pi3(t) and Pii(t) loci. We developed three PCR-based dominant markers (JJ80-T3, JJ81-T3, and JJ113-T3) from three previously identified BIBAC clones-JJ80, JJ81, and JJ113-that are linked to the Pi5(t) locus. PCR analysis of 24 monogenic lines revealed that these markers are present only in lines that carry Pi5(t), Pi3(t), and Pii(t). PCR and DNA gel-blot analysis of candidate resistance lines using JJ80-T3, JJ81-T3, and JJ113-T3 indicated that Tetep is the likely donor of Pi5(t). Of the 184 rice varieties tested, 34 carried the JJ80-T3-, JJ81-T3-, and JJ113-T3-specific bands. Disease evaluation of those 34 varieties revealed that all conferred resistance to PO6-6. The genomic structure of three of these resistant varieties (i.e., IR72, Taebaeg, Jahyangdo) is most similar to that of Pi5(t). Our results demonstrate the usefulness of the JJ80-T3, JJ81-T3, and JJ113-T3 markers for MAS for M. grisea resistance.

Light-regulated differential expression of pea chloroplast and cytosolic fructose-1,6-bisphosphatases

The light-regulated differential expression of pea chloroplast and cytosolic fructose-1,6-bisphosphatases (FBPase) was investigated using enzyme activity assay, immunoblot, and Northern blot analyses. The enzyme activities of both chloroplast and cytosolic FBPases gradually increased under continuous white light illumination, although the increase in chloroplast FBPase was more drastic. Northern and immunoblot analyses also indicated that light stimulated the expression of both enzymes. Enzyme activity and the transcript levels of both enzymes gradually decreased under the dark treatment, although protein levels were unchanged for up to 24 h following the initiation of culture in the dark, indicating that reversible modifications of the enzymes may occur during the transition from light to dark (or the reverse). Light pulse experiments using blue (420 nm) and red/far-red (660/730 nm) light were carried out to analyze the photoreceptors related to the light-mediated expression of both enzymes. Expression of the chloroplast enzyme was very sensitive to red or far-red light pulses-it was induced by red light, but suppressed by far-red light pulses, as determined by enzyme activity, immunoblot, and Northern blot analyses, suggesting that red light signaling is involved in the control of chloroplast FBPase expression. However, cytosolic FBPase was virtually insensitive to blue or red/far-red light pulses in terms of enzyme activity, as determined by protein and transcript levels, indicating that cytosolic enzyme expression is not directly regulated by light signals. Instead, the expression of the cytosolic enzyme may be closely related to photosynthetic energy conversion accompanied by continuous white light irradiation.

Gene amplification and expression of the DNA repair enzyme, N-methylpurine-DNA glycosylase (MPG) in HPV-infected cervical neoplasias

BACKGROUND

Lethal and mutagenic damages of DNA is caused by a variety of agents including viruses. It is known that HPV is one of the major causes of cervical carcinogenesis and that cells eliminate DNA lesions with DNA repair enzymes. However, the role of N-methylpurine-DNA glycosylase (MPG) is not known in the development of cervical cancer.

MATERIALS AND METHODS

Multiplex polymerase chain reaction (PCR) was used for the detection and typing of HPV in the biopsy. Gene amplification of MPG was measured by a PCR-based assay. The mRNA levels of MPG were determined by reverse transcription-PCR using hypoxanthine-guanine phosphoribosyl transferase as the reference gene. An immunohistochemical technique was used to examine the distribution of MPG in the tissues.

RESULTS

Of 68 Korean cervical neoplasia patients, 86.8% showed HPV infection. High-risk HPV 16/18 were the most prevalent but positive only in 47.3% of the invasive cancer patients. Gene amplification of MPG was significantly increased in high-risk HPV-infected tissues as compared to low-risk HPV-infected and normal tissues (p < 0.05). The mRNA levels of MPG were higher in HPV-infected invasive carcinoma than normal cervical tissues. Immunohistochemical staining revealed that the intracellular expression and distribution (localization) of MPG altered in the cervical neoplasia. Interestingly, MPG expression in CIN III and invasive carcinoma (IC) was much higher than normal and CIN I. Granular positivity of MPG was notable in the perinuclear regions of the cytoplasm in HPV-infected invasive cancer.

CONCLUSION

This is the first report on MPG expression in cervical neoplasia. Our results indicate that the gene amplification and expression of MPG were increased in high-risk HPV-infected cervical neoplasias and the intracellular distribution of MPG protein was altered, suggesting a role of MPG in carcinogenesis.

Purification and characterization of precarthamin decarboxylase from the yellow petals of Carthamus tinctorius L

Carthamin, a red quinochalcone pigment in safflower (Carthamus tinctorius L.), is enzymatically converted from a yellow precursor, precarthamin. The enzyme, which catalyzes the oxidative decarboxylation of precarthamin to carthamin, was purified to apparent homogeneity from yellow petals of safflower and named precarthamin decarboxylase. The molecular mass of the denatured enzyme was estimated as 33 kDa by SDS-PAGE. The molecular mass of the native enzyme was determined by gel filtration chromatography to be 24 kDa; thus, the native enzyme is a monomer. The optimum pH of the enzyme was 5.0. The enzyme activity was inhibited by Mn2+, Fe2+, and Cu2+ and sharply decreased at temperatures higher than 50 degrees C for 10 min. The activation energy and the Arrhenius frequency factor of the enzyme reaction were 19.7 kcal mol(-1) and 9.94 x 10(11) s(-1), respectively. The saturation curve of precarthamin showed that the enzyme follows Michaelis-Menten kinetics. The Km and Vmax of the enzyme were calculated as 164 microM and 29.2 nmol/ min, respectively. The turnover number (kcat) of the enzyme was calculated as 1.42 x 10(2) s(-1). The enzyme activity was severely inhibited by reducing agents such as glutathione and DTT at pH 5.0, suggesting that a disulfide bond may play an important role in enzyme function.

Enzymatic conversion of precarthamin to carthamin by a purified enzyme from the yellow petals of safflower

Precarthamin, a yellow precursor of carthamin, was efficiently isolated from the yellow petals of safflower (Carthamus tinctorius L. ) with Sephadex LH-20 column chromatography and preparative HPLC, and identified with UV-vis and NMR spectrometry. The UV-vis spectrum of precarthamin showed lambda(max) of 238 and 406 nm in MeOH. The molar extinction coefficients of precarthamin at 406 nm in MeOH and 50 mM citrate buffer (pH 5.0) were 59 000 M(-)(1) cm(-)(1) and 45 400 M(-)(1) cm(-)(1), respectively. The isolated and structurally identified precarthamin was converted to a red pigment by a homogeneously purified enzyme from the immature petals of safflower in 50 mM citrate buffer (pH 5.0). The enzymatically converted red pigment was identified as carthamin, a red pigment of safflower by TLC, HPLC, and UV-vis spectral analysis.

Phytochrome signalling is mediated through nucleoside diphosphate kinase 2

Because plants are sessile, they have developed intricate strategies to adapt to changing environmental variables, including light. Their growth and development, from germination to flowering, is critically influenced by light, particularly at red (660 nm) and far-red (730 nm) wavelengths. Higher plants perceive red and far-red light by means of specific light sensors called phytochromes(A-E). However, very little is known about how light signals are transduced to elicit responses in plants. Here we report that nucleoside diphosphate kinase 2 (NDPK2) is an upstream component in the phytochrome signalling pathway in the plant Arabidopsis thaliana. In animal and human cells, NDPK acts as a tumour suppressor. We show that recombinant NDPK2 in Arabidopsis preferentially binds to the red-light-activated form of phytochrome in vitro and that this interaction increases the activity of recombinant NDPK2. Furthermore, a mutant lacking NDPK2 showed a partial defect in responses to both red and farred light, including cotyledon opening and greening. These results indicate that NDPK2 is a positive signalling component of the phytochrome-mediated light-signal-transduction pathway in Arabidopsis.

Physical stability of shikonin derivatives from the roots of Lithospermum erythrorhizon cultivated in Korea

Five red shikonin pigments, deoxyshikonin, shikonin, acetylshikonin, isobutylshikonin, and beta-hydroxyisovalerylshikonin, were isolated from the roots of Lithospermum erythrorhizon cultivated in Korea. The purified pigments were red, purple, and blue at acidic, neutral, and alkaline pH values, respectively. Physical stability of the purified pigments against heat and light in an aqueous solution was examined for possible value-added food colorants. The thermal degradation reactions were carried out at pH 3.0 (50 mM glycine buffer) in 50% EtOH/H(2)O. Deoxyshikonin (t(1/2) = 14.6 h, 60 degrees C) and isobutylshikinin (t(1/2) = 19.3 h, 60 degrees C) are relatively less stable than other shikonin derivatives (t(1/2) = 40-50 h, 60 degrees C). Activation energies of thermal degradation of the isolated pigments were calculated. The activation energy of deoxyshikonin was the highest (12.5 kcal mol(-)(1)) and that of beta-hydroxyisovalerylshikonin was the lowest (1.71 kcal mol(-)(1)) value. Light stabilities of the pigments were similar to each other in that the half-life values of photodegradation for 20000 lx light intensity were 4.2-5.1 h.

Propionylshikonin from the roots of Lithospermum erythrorhizon

A shikonin derivative was isolated from the roots of Lithospermum erythrorhizon with silica gel column chromatography and preparative TLC. The structure of the isolated pigment was identified as propionylshikonin by NMR and mass spectrometric analysis. The isolation of propionylshiknin was for the first time in the nature.

Large-scale analysis of expressed genes from the leaf of oilseed rape (Brassica napus L.)

While the number of leaf-specific expressed genes is estimated to be approximately 6,000, an overview of gene diversity and expression patterns in the leaf of oilseed rape (Brassica napus L.) has not yet been reported. In an effort to understand gene expression patterns and to identify new genes, we generated 754 expressed sequence tags (ESTs) from the leaf of B. napus. By comparing them to public databases, we showed that 204 of the ESTs (27.1%) have sequence homology to known genes, with 52 of them (6.9%) matching to genes not previously studied in B. napus. The most abundant transcripts were found to be involved in photosynthesis and energy metabolism. When compared with maize leaf ESTs and rice leaf ESTs, the pattern of gene expression was different depending on the developmental stages of the leaf.

Molecular characterization of a cDNA encoding chloroplastic fructose-1,6-bisphosphatase from soybean (Glycine max L.)

A full-length cDNA of soybean chloroplastic fructose-1,6-bisphosphatase was cloned and sequenced. The cDNA contained 1321 bp with 5' (26 bp) and 3' (88 bp) untranslated regions. The open reading frame of the cDNA contained 1206 bp corresponding to a polypeptide of 402 amino acids with 50 amino acid residues of a transit peptide at N-terminus that is necessary for transport into the chloroplast. A unique site relevant to the action of thioredoxin f was conserved at 221 amino acid residue. Northern blot analysis indicated that the expression of the enzyme was regulated by light illumination.

Light signal transduction mediated by phytochromes: preliminary studies and possible approaches

Phytochromes mediate a variety of developmental and growth processes involved in the photomorphogenesis of plants. In this article, we review the current understanding of the structure and function of the photoreceptor, discuss some very preliminary results, and offer speculations and even conjectures that may elicit future studies into the molecular mechanisms of the phytochrome-mediated light signal transduction in plants.

RecA-mediated strand exchange reactions between duplex DNA molecules containing damaged bases, deletions, and insertions

RecA protein from Escherichia coli promotes homologous pairing and strand exchange between duplex DNA molecules if one is partially single-stranded. Using linear duplexes and circles with a single-stranded gap as the substrates, this reaction generates nicked circular heteroduplex DNA and linear molecules with single-stranded ends. The completion of strand exchange can be demonstrated by the production of nicked circular heteroduplex DNA detected by gel electrophoresis and autoradiography using radiolabeled linear molecules. When the effect of ultraviolet damage to the substrate DNA was tested, strand exchange was found to pass 30 or more pyrimidine dimers in each duplex. In contrast, exchanges were blocked or severely slowed by interstrand cross-links and monoadducts produced by psoralen and 360 nm light. Deletions and insertions of from 4 to 38 base pairs in the DNA substrates had little effect on the production of nicked circular heteroduplex DNA. However, those of 120 base pairs, or greater, reduced the product yield to a level below the threshold of detection. These results contrast with those obtained in related three-stranded reactions (Bianchi, M. E., and Radding, C. M. (1984) Cell 35, 511-520), in which stable heteroduplex products with 500 or 1300 unpaired bases were obtained when the insert was located within a single-stranded circular substrate.

Tetranitromethane oxidation of phytochrome chromophore as a function of spectral form and molecular weight

Tetranitromethane bleaches Avena phytochrome. The phytochrome (far-red absorbing form; Pfr) chromophore of 124 kilodalton (kD) phytochrome is oxidized 8 times more rapidly than the red absorbing form (Pr). Proteolysis of the 124 kD molecule to the extensively studied mixture of 118 and 114 kD polypeptides increases the rate of oxidation of Pfr 5-fold without affecting the rate of Pr oxidation. As a result, the Pfr form of 118/114 kD preparations is oxidized at a rate 40 times greater than the Pr form. Further proteolytic degradation of the chromoprotein to 60 kD results in an additional increase in the oxidation rates of both Pr and Pfr. These differences in reactivity to tetranitromethane indicate that the chromophore of Pfr is either intrinsically more chemically reactive and/or physically more accessible than the Pr chromophore and that the reactivity/accessibility of both spectral forms is increased by proteolysis. The enhanced reactivity of the Pfr chromophore after proteolytic cleavage of the 6 to 10 kD polypeptide segment(s) from the 124 kD species is further evidence that these segment(s) affect the environment of the native photoreceptor.

Molecular topography of phytochrome as deduced from the tritium-exchange method

The hydrogen-tritium-exchange measurements on phytochrome have been performed to detect the conformational differences between the red-absorbing (Pr) and the far-red absorbing (Pfr) forms of phytochrome. The large and small Pfr molecules revealed more exchangeable protons that did the corresponding Pr molecules by 96 and 70 protons, respectively. These results suggest that the Pr leads to Pfr phototransformation is accompanied by an additional exposure of the peptide chains in the Pfr molecule. Of 1682 theoretically exchangeable hydrogens in undegraded phytochrome, only 442 (26%) and 346 (21%) protons were found to be exchangeable (excluding instantaneously exchangeable protons that cannot be determined by the present method). Thus, the phytochrome protein appears to be compact and highly folded. The kinetic analyses of the tritium exchange-out curves indicate that two kinetically different groups are responsible for the conformational differences between the Pr and Pfr forms of phytochrome. These components are due to (1) the exposure of hydrogen-bonded peptide segments (alpha helix and/or beta-pleated sheet) in the chromophore vicinity of Pfr and (2) the exposure of hydrogen-bonded peptide segments on the chromophore peptide domain as well as on the chromophore-free tryptic domain of undegraded phytochrome.

Hydrophobic properties of phytochrome as probed by 8-anilinonaphthalene-1-sulfonate fluorescence

8-Anilinonaphthalene-1-sulfonate (ANS) complexes with phytochrome, exhibiting a higher affinity for the Pfr form of phytochrome than for the Pr form. ANS fluorescence is enhanced by the additional binding of ANS to Pfr upon transformation of phytochrome from Pr to Pfr. The specific site of ANS binding appears to be the hydrophobic surface area of the protein, which becomes at least partially exposed in the Pfr form. An exposed, hydrophobic surface area in the Pfr phytochrome has been confirmed by the effects of ANS on the phototransformation of phytochrome. ANS accelerates the Pr leads to Pfr phototransformation, and it inhibits Pfr leads to Pr photoreversion and dark reversion. These effects are interpretable in terms of competitive binding of ANS to the chromophore binding site. Binding of ANS results in a drastic bleaching of the chromophore's absorption bands at 660 and 730 nm, particularly of the latter. This can be attributed to the exposed chromophore, which tends to resume a cyclic conformation with concomitant blue shift and hypochromism of the Qy bands. Sodium dithionite counteracts the inhibitory effects of ANS on the dark reversion of Pfr to Pr, and its effect on the biphasic kinetics of the reversion has been discussed in terms of the Pfr model proposed.