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Biomedical subjects

C Lange

Publications and source records attributed to C Lange.

At least 127 records · Page 7Linked to original sources
PubMed1992

The components of the venom of a spider Scodra griseipes. 1. Analysis of low molecular weight products using gas chromatography/mass spectrometry.

Low molecular weight venom constituents of the spider Scodra griseipes have been derivatized using bis(trimethylsilyl)-trifluoroacetamide and pentafluoropropionic anhydride. Examination of these derivatives by coupled gas chromatography/mass spectrometry using electron ionization or ammonia- or isobutane-chemical ionization allows their structural identification. Comparisons have also been made with retention time and mass spectra of the pure compounds. Four acids: phosphoric, lactic, citric, gamma-aminobutyric (neurotransmitter) and four basic biogenic amines: putrescine, cadaverine, spermidine and spermine have been found.

Animals↗
PubMed1992

The components of the venom of a spider Scodra griseipes. 2. Structural information on biogenic amines using tandem mass spectrometry.

Biogenic amines, which are components of tarantula Scodra griseipes venom, are studied using tandem mass spectrometry. Their heptafluoropropionic (PFP) derivatives are ionized under electron impact and isobutane-chemical ionization. Daughter- and parent-ion mass spectra under collisionally activated dissociation conditions provide a more detailed study of such derivatives. Discrimination of di(PFP)amines and tri and tetra(PFP)amines is possible because of the presence of diagnostic ions induced by collision.

Biogenic Polyamines↗
PubMed1992

Cuticular hydrocarbons of Calliphora vomitoria (Diptera): relation to age and sex.

Changes in epicuticular hydrocarbon content and composition were examined from 3 to 120 hr postemergence in both sexes of Calliphora vomitoria. n-Alkanes and mono- and dimethylalkanes with 20 to 31 carbon atoms were the major hydrocarbons detected. Alkenes were only detected in the females. Males had fewer hydrocarbons (40 versus 49 for the females). In males this number remained constant from 3 to 120 hr, whereas in females the number increased progressively from 3 to 48 hr. The males had a greater total of hydrocarbons than the females (x6 versus x3.5). They had significantly more hydrocarbons by 48 hr, the time of sexual maturation, while in females, the hydrocarbon content increased between 6 and 24 hr postemergence, just before the onset of previtellogenesis. Hydrocarbon synthesis continued up to 120 hr in males, but remained constant in the females after 24 hr. Hydrocarbon composition differed in males and females and between the young (3 and 6 hr) and the older animals (24 to 120 hr). The young animals were characterized by the presence of monomethylalkanes with chain lengths over 25C and the older animals by monomethylalkanes with chain lengths less than 25C. Alkenes were found only in females. The males were characterized by the presence of di- and monomethylalkanes with 23, 24, and 26 carbon atoms.

Aging↗
PubMed1992

[Follow-up of 551 patients with node-negative breast cancer].

To evaluate the prognostic significance of established clinical, histological, and biochemical factors, we examined the survival data of 551 node-negative breast cancer patients. At a median follow-up of 5 years, we found 114 recurrences, 79 of them at distant sites. 41 patients died. 84 patients with less than 8 examined lymph nodes, adjuvant systemic treatment, or treatment differing from standard procedures, had a statistically significant shorter overall survival and were excluded from further analysis. With regard to relapse-free and overall survival univariate and multivariate analyses of the remaining 467 patients revealed only few factors with prognostic significance. In multivariate analysis of overall survival by the Cox regression model, statistically significant prognostic value was limited to three factors: lymphangiosis carcinomatosa (relative risk 4.8, 95%-confidence interval 2.0-11.7), postmenopausal status (0.38, 0.17-0.84), and positive progesterone receptor status (0.37, 0.14-1.0). In addition, there was a trend (p = 0.075) of prolonged survival in patients with Bloom and Richardson grade I cancers. The few prognostic factors found were able to identify patients with very good, as well as very bad prognosis. However, for the majority of node-negative breast cancer patients, estimation of prognosis remains unsatisfactory. Therefore, further independent prognostic factors are necessary.

Actuarial Analysis↗
PubMed1991

'Pseudo' domains in phage-encoded DNA methyltransferases.

5-Cytosine-DNA-methyltransferases, which are found in many organisms ranging from bacteriophages to mammals, transfer a methyl group from S-adenosylmethionine to the carbon-5 of a cytosine residue in specific DNA target sequences. Some phage-encoded methyltransferases methylate more than one sequence: these enzymes contain several independent target-recognizing domains each responsible for recognizing a different site. The amino-acid sequences of these multispecific methyltransferases reveal that some enzymes in addition carry domains that do not contribute to the enzymes' methylation potential, but strongly resemble previously identified target-recognizing domains. Here we show that introducing defined amino-acid alterations into these inactive domains endows these enzymes with additional methylation specificities. Gel retardation analysis demonstrates that these novel methylation specificities correlate with the acquisition of additional DNA-binding potential of the proteins.

Amino Acid Sequence↗
PubMed1991

Behaviour studies of the fungicide cymoxanil in two strains of the fungus Botrytis cinerea and in haemolymph of locust and lobster. I. In situ monitoring by internal surface reversed-phase high-performance liquid chromatography.

A method for following the metabolism of the fungicide cymoxanil in various biological media is described. By using a recently developed high-performance liquid chromatographic method, with an internal surface reversed-phase column, it is unnecessary to clean up the sample before analysis. Thus this technique makes monitoring in fungi as well as in arthropod haemolymph easier and faster.

Acetamides↗
PubMed1991

Direct in vitro and in vivo monitoring of destruxins metabolism in insects using internal surface reversed-phase high-performance liquid chromatography. I. Behaviour of E destruxin in locusts.

High-performance liquid chromatography with internal surface reversed-phase packing provides an analytical tool for studying the in vitro and in vivo metabolism of A and E destruxins in the haemolymph and various organs of male adults of Locusta migratoria. A slight amount of injected E destruxin is shown to be hydrated into E-diol destruxin in the haemolymph. The rest of the toxin is recovered unchanged in the fat-body, pericardial tissues and Malpighian tubules, and some further E-diol destruxin formation occurs in these organs. Because E-diol destruxin is only weakly toxic, this appears to be a detoxication process.

Animals↗
PubMed1991

M.H2I, a multispecific 5C-DNA methyltransferase encoded by Bacillus amyloliquefaciens phage H2.

Bacillus amyloliquefaciens phage H2 codes for a multispecific cytosine-5-DNA- methyltransferase (MTase), M.H2I, which methylates GGCC, GCNGC and [sequence: see text] target sequences. The gene coding for M.H2I was cloned in Escherichia coli and its nucleotide (nt) sequence was determined. It consists of 1509 bp, corresponding to a protein of 503 amino acids (aa) with a calculated Mr of 57,166. A comparison of the aa sequence of M.H2I with those of the multispecific MTases encoded by Bacillus subtilis phages SPR, phi 3T and rho 11S, revealed that M.H2I is closely related to these enzymes. A very high degree of homology was observed between M.H2I and M.rho 11SI, with 96.2% aa identity and 97.8% nt identity of the corresponding genes.

Amino Acid Sequence↗
PubMed1991

Cross-protection against four species of chicken coccidia with a single recombinant antigen.

A cDNA clone, SO7', from an Eimeria tenella cDNA library was inserted into the high-expression vector pJC264 and was expressed in Escherichia coli as a fusion protein, CheY-SO7', with a molecular mass of approximately 36 kDa. By using the purified recombinant antigen to immunize young chicks, it was demonstrated that a single dose, without adjuvant, not only protected against severe coccidiosis induced by infection with E. tenella but also protected chicks challenged with the heterologous species Eimeria acervulina, E. maxima, and E. necatrix. By using rabbit antiserum raised against recombinant CheY-SO7', Western blot (immunoblot) analysis of sporulated oocysts of all seven major species of chicken coccidia showed that all species tested contained proteins characteristic of the B class of antigens, of which CheY-SO7' is representative. It seems likely that a single B antigen could protect chickens against severe coccidiosis caused by infection with any of these Eimeria species. Although chicks exposed to prolonged, natural infection develop antibodies to B antigen, active immunization of young chicks with a protective dose of CheY-SO7' does not elicit a humoral antibody response, suggesting that the partial protection results from cell-mediated effector mechanisms. In addition, the cross-protective nature of the immunity indicates that the response to B antigen is different from that induced by natural infection, which elicits a species-specific immunity. To date, the protection induced by B antigen immunization, although remarkable for a single recombinant protein, is not sufficient to compete with prophylactic chemotherapy.

Animals↗
PubMed1991

[Social psychological barriers to compliance in group and individual prophylaxis].

In a long-term study of 700 school children attitudes and behaviour related to dental hygiene were registered and collated with findings on caries and oral hygiene. The data indicating developments in the 12 - 14 year old group showed that youths are well informed about the condition of their teeth, but are increasingly unwilling to accept treatment and advice offered by dentists. Potential barriers to compliance with prophylactic and therapeutic measures are a lack of success in school studies, insufficient accentuation of independence in the educational and child-raising process and a lack of communication between dentist and youths.

Adolescent↗
PubMed1990

[Studies on juveniles' education for health of teeth and mouth. 2. Juveniles' knowledge of dental health and behavior].

General recommendations about healthy way of life and dental health are well-known to juveniles aged 12 to 16; but detailed information which completes and reinforces this general knowledge in a useful way is to a large extent lacking. Knowledge and behaviour of juveniles correlate with age, sex and success at school. An important role in developing a healthy way of life plays the family education. Point of contact for the dentist is the upgrading of dental screenings by a conform-intensive arrangement of these direct and very individual consultations.

Adolescent↗
PubMed1990

[Early diagnosis of congenital disorders of color vision with the Velhagen "Pflügerhaken Color Charts for evaluating color perception" in 3,375 preschool children].

In three series of examinations, 3375 male preschool-age children and 93 adult normal trichromates were tested using the Velhagen Pflügerhaken charts. The authors recommend modifying the evaluation of the results slightly by introducing a "doubteful" category for children who make one mistake or who show hesitation and lack of assurance in interpreting the charts. Using this modified form of assessment, diagnoses of "probably achromatopic" and "doubtful" were made in 7.16% and 2.13% respectively of 1689 preschool-age boys. The failure rate during the test and the duration of the examination were age-dependent, and declined with increasing age from 4.15% to 0.45% and from 1.18 min to 0.59 min, respectively. Most mistakes were made with charts nos. 9, 3, and 5. The results of tests with Pflügerhaken charts are fully comparable with those of other internationally used tests for adults. They can be recommended for screening preschool-age children.

Adult↗
PubMed1989

Recombinant interferon-gamma inhibits cell invasion by Eimeria tenella.

Treatment of primary chicken kidney (CK) cultures with supernatants from concanavalin A-treated Eimeria tenella-immune avian splenic T cells significantly inhibited the invasion of the cells by sporozoites of E. tenella. Biochemical evaluation of this T-cell factor is consistent with the idea that this anti-Eimeria activity in the avian lymphokines is due to interferon-gamma (IFN-gamma). We then studied the effect of recombinant bovine and human IFN-gamma on the invasion of sporozoites of E. tenella in cultures of bovine and human cell lines, respectively. The initial infection of either the Madin-Darby bovine kidney cell line (MDBK) or the human larynx epidermoid carcinoma cell line (HEp-2) by the obligate intracellular protozoan parasite E. tenella was inhibited following a 24-h pretreatment with recombinant bovine or human IFN-gamma, respectively. The IFN-gamma-mediated inhibition was dose-dependent for both cell lines. Incubation of sporozoites of E. tenella with IFN-gamma alone before infection had no detectable inhibitory effect on cell invasion of either cell line by the parasite. In addition, the establishment of the antiinfective cellular state by IFN-gamma required at least a 16- to 24-h preincubation for significant inhibitory effects. These results are suggestive of a direct effect of the IFN-gamma on the host cells and not on the parasite themselves. Taken together these studies provide evidence for a role for IFN-gamma as a nonspecific mediator of host protection against coccidiosis.

Animals↗
PubMed1989

Interferon-gamma-mediated inhibition of the development of Eimeria tenella in cultured cells.

The effect of treating cultured Madin-Darby bovine kidney cells (MDBK) with recombinant bovine interferon-alpha 1 (IFN-alpha 1) or recombinant bovine interferon-gamma (IFN-gamma) on the intracellular development of Eimeria tenella was studied. Treatment of the MDBK cells with IFN alpha-1 for 24 hr before infection and for 48 hr after infection had no effect on the development of E. tenella. However, following the same treatment regime with serial dilutions of IFN-gamma induced a significant reduction in the number of total intracellular parasites (sporozoites, trophozoites, and meronts) compared to the untreated controls. Of these intracellular parasites, less than 30% had developed beyond the sporozoite stage. These results are suggestive of a role for IFN-gamma in protecting or limiting the development of E. tenella in their host cells. These results could be relevant to the control of these organisms and may be exploited for use with a coccidiosis vaccine.

Animals↗
PubMed1989

[Juveniles' education for oral health. 1. Juveniles' position to health of teeth and stomatological care in children].

About one forth each of juveniles aged between 12 and 16 years which have been questioned in a written form to the topic of health declare a particular positive attitude towards a healthy way of live or a negative attitude towards dental health. The compliance of juveniles to dental care is influenced both by sex, age, achievements at school, family, group integration and their motivation structure and by paedodontics care.

Adolescent↗
PubMed1988

Primary lymphoma of the liver.

Nine adult white men ranging in age from 27 to 76 (mean, 55 years) were treated for primary hepatic lymphoma between 1972 and 1986 at the Memorial Sloan-Kettering Cancer Center. Six patients presented with right upper quadrant or epigastric pain or discomfort, and three patients complained of fatigue and lethargy. Fever and night sweats were evident in two, and two patients had lost weight. One patient was asymptomatic; the liver mass was detected during the work-up for cancer of the prostate. Seven patients on whom computerized tomography was performed all had solitary masses in the liver although in three of them tumor had extended into both lobes as noticed at surgery. One had additional porta hepatic lymph node metastasis. Eight patients underwent an exploratory laparotomy; four had hepatic resection, and four had wedge biopsies of unresectable liver tumor. One patient had a percutaneous needle biopsy of the liver. Eight patients received combination chemotherapy. Six patients are alive, five of whom are in initial complete remission. All three patients who died had persistent or recurrent disease in the liver. The results of therapy and surgery to date in these and in other cases in the literature are encouraging.

Adult↗
PubMed1988

Alkaloid venom of European ants in the genus Monomorium. Site of synthesis, identification and quantification.

The venom of the European Ant Monomorium is composed of five alkaloids: three 2.5 transdialkylpyrrolidines and two 2.5 transdialkylpyrrolines. The venom is synthesized by a glandular complex composed of a biramous external filamentous gland, and a single internal gland invaginated into the reservoir. External glands and the proximal two-thirds of the internal gland are composed of glandular units, with one glandular cell and one associated duct cell. Glandular cells contain numerous giant mitochondria, a well-developed smooth endoplasmic reticulum and enigmatic rod-shaped structures. The secretory product is electron-lucent. The distal third of the internal gland is composed of 38-48 large secretory cells issuing directly into the reservoir. Their secretory product presents the same characteristics as the venom accumulated in the reservoir (opacity, affinity to stains and osmium).

Animals↗