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1.
Nat Commun ; 13(1): 5219, 2022 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-36064947

RESUMEN

The development dynamics and self-organization of glandular branched epithelia is of utmost importance for our understanding of diverse processes ranging from normal tissue growth to the growth of cancerous tissues. Using single primary murine pancreatic ductal adenocarcinoma (PDAC) cells embedded in a collagen matrix and adapted media supplementation, we generate organoids that self-organize into highly branched structures displaying a seamless lumen connecting terminal end buds, replicating in vivo PDAC architecture. We identify distinct morphogenesis phases, each characterized by a unique pattern of cell invasion, matrix deformation, protein expression, and respective molecular dependencies. We propose a minimal theoretical model of a branching and proliferating tissue, capturing the dynamics of the first phases. Observing the interaction of morphogenesis, mechanical environment and gene expression in vitro sets a benchmark for the understanding of self-organization processes governing complex organoid structure formation processes and branching morphogenesis.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animales , Carcinoma Ductal Pancreático/patología , Ratones , Morfogénesis , Organoides/metabolismo , Páncreas/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas
2.
J Chem Ecol ; 32(4): 767-78, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16718570

RESUMEN

The subsocial tenebrionid Parastizopus armaticeps Pér. is parasitized by the closely related Eremostibes opacus Koch (Coleoptera: Tenebrionidae). We found that the pygidial defensive secretions of both species are similar and contain a mixture of 1,4-benzoquinones, 1-alkenes, and monoterpene hydrocarbons. The 1-alkenes are dominated by 1-undecene, with admixtures of 1-tridecene in both species and 1-pentadecene in P. armaticeps only. Methyl- and ethyl-1,4-benzoquinone are the major quinones of the secretions of both species. The monoterpene fractions consist of (-)-alpha-pinene, (-)-camphene, sabinene, (-)-beta-pinene, and (-)-limonene. Volatiles trapped with Porapak Q at the entrance to the breeding burrows of P. armaticeps were identified as components of the defensive secretion. However, in contrast to the secretion, the 1,4-benzoquinones were almost completely absent in the volatiles. Bioassays investigating attraction showed that the cleptoparasite E. opacus was drawn to the monoterpene hydrocarbons, produced by P. armaticeps, and deterred by the 1,4-benzoquinones. The 1-alkenes had no effect. Among the monoterpenes, only (-)-camphene was attractive to E. opacus. This is one of the rare cases of chemical exploitation of defensive allomones, and the first based on odor homology. We have drawn an evolutionary scenario including various functional changes in the defensive secretion compounds, leading to the kairomonal exploitation.


Asunto(s)
Escarabajos/fisiología , Escarabajos/parasitología , Feromonas/metabolismo , Comunicación Animal , Animales , Interacciones Huésped-Parásitos , Hidrocarburos/análisis , Feromonas/química , Glándulas Odoríferas/metabolismo , Volatilización
3.
Biopolymers ; 82(4): 286-90, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16421858

RESUMEN

UV-resonance Raman spectroscopy is applied as a method for the identification of lactic acid bacteria from yogurt. Eight different strains of bacteria from Lactobacillus acidophilus, L. delbrueckii ssp. bulgaricus, and Streptococcus thermophilus were investigated. At an excitation wavelength of 244 nm signals from nucleic acids and proteins are selectively enhanced. Classification was accomplished using different chemometric methods. In a first attempt, the unsupervised methods hierarchical cluster analysis and principal component analysis were applied to investigate natural grouping in the data. In a second step the spectra were analyzed using several supervised methods: K-nearest neighbor classifier, nearest mean classifier, linear discriminant analysis, and support vector machines.


Asunto(s)
Lactobacillus/clasificación , Espectrometría Raman/métodos , Yogur/microbiología , Análisis por Conglomerados , Análisis Discriminante , Microbiología de Alimentos , Lactobacillus/química , Lactobacillus acidophilus/química , Lactobacillus acidophilus/clasificación , Lactobacillus delbrueckii/química , Lactobacillus delbrueckii/clasificación , Análisis de Componente Principal/métodos , Streptococcus thermophilus/química , Streptococcus thermophilus/clasificación
4.
Biopolymers ; 82(4): 312-6, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16421914

RESUMEN

For a fast identification of eukaryotic cells such as yeast species without a cultivation step it should be possible to perform the investigation on only one single cell. Since yeasts as eukaryotes are heterogeneous and their Raman spectra are therefore dependent on the measuring position, one Raman spectra is not representative of the whole cell. In this contribution we demonstrate the application of average Raman spectra of a line scan over single yeast cells. These average spectra are used for classification with the help of a support vector machine.


Asunto(s)
Células Eucariotas/clasificación , Espectrometría Raman/métodos , Candida/química , Candida/clasificación , Candida/citología , Células Eucariotas/química , Células Eucariotas/citología , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/clasificación , Saccharomyces cerevisiae/citología , Levaduras/química , Levaduras/clasificación , Levaduras/citología
5.
Analyst ; 130(11): 1543-50, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16222378

RESUMEN

Microbial contamination is not only a medical problem, but also plays a large role in pharmaceutical clean room production and food processing technology. Therefore many techniques were developed to achieve differentiation and identification of microorganisms. Among these methods vibrational spectroscopic techniques (IR, Raman and SERS) are useful tools because of their rapidity and sensitivity. Recently we have shown that micro-Raman spectroscopy in combination with a support vector machine is an extremely capable approach for a fast and reliable, non-destructive online identification of single bacteria belonging to different genera. In order to simulate different environmental conditions we analyzed in this contribution different Staphylococcus strains with varying cultivation conditions in order to evaluate our method with a reliable dataset. First, micro-Raman spectra of the bulk material and single bacterial cells that were grown under the same conditions were recorded and used separately for a distinct chemotaxonomic classification of the strains. Furthermore Raman spectra were recorded from single bacterial cells that were cultured under various conditions to study the influence of cultivation on the discrimination ability. This dataset was analyzed both with a hierarchical cluster analysis (HCA) and a support vector machine (SVM).


Asunto(s)
Staphylococcus/aislamiento & purificación , Técnicas Bacteriológicas , Microquímica/métodos , Espectrometría Raman/métodos
6.
Mol Phylogenet Evol ; 18(2): 202-16, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11161756

RESUMEN

The phylogeny of the genus Aleochara was previously poorly understood due to difficulties with phylogenetic reconstruction by morphological characters. We present here a phylogeny based on the sequences of a 2022-bp fragment of the COI/II genes; 50 Aleochara and 10 outgroup species were included in the analysis. We used parsimony, minimum-evolution, and maximum-likelihood analyses to infer the phylogeny of the group. Our data do not support the commonly assumed sister group relationship between Aleocharini and Hoplandriini. Aleochara is resolved as a monophylum, although A. clavicornis might not belong to the genus. Within Aleochara, there are two large monophyletic clades. Many of the existing subgenera are shown to be para- or polyphyletic; others are likely to be monophyletic. Tinotus morion, previously assigned to the Hoplandriini, is strongly supported as belonging to Aleochara. According to our data, the mesosternal carina that has been used as an important character for classification has arisen and been reduced independently in several clades within Aleochara.


Asunto(s)
Escarabajos/clasificación , Escarabajos/genética , ADN Mitocondrial/genética , Complejo IV de Transporte de Electrones/genética , Mitocondrias/enzimología , Animales , Evolución Molecular , Funciones de Verosimilitud , Modelos Genéticos , Filogenia , Análisis de Secuencia de ADN
7.
Tissue Cell ; 31(4): 413-20, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18627865

RESUMEN

The morphology of mature spermatozoa of the rove beetle Aleochara bilineata was examined by using scanning and transmission electron microscopy. They are about 1000 mum long and filiform. The acrosome and the nucleus are elongate and each about 20 mum long. A well-developed centriole adjunct region connects the nucleus with the sperm tail. The axoneme reveals the 9 + 9 + 2 pattern of the pterygote sperm flagellum. Two accessory bodies and two mitochondrial derivatives with paracrystalline inclusions are present. Cristae are reduced to the cortical zone of the derivatives. Cytochrome-c oxidase activity was detected within the cristae by DAB-reaction. The energy metabolism of the spermatozoa was investigated by using different inhibitors affecting the mitochondrial and cytoplasmic metabolic pathways. Sperm movement was used as an indicator for the utilization of ATP by the axoneme. In control experiments, the duration of motility was longer than 45 min. In the presence of atractyloside or potassium cyanide the motility duration was not affected. On the other hand, iodoacetic acid in the medium stopped sperm motility within 15 min. This indicates that sperm energy metabolism mainly depends on the glycolytic pathway.

8.
Electrophoresis ; 19(2): 158-63, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9548274

RESUMEN

Oligonucleotide fingerprinting was performed on three beetle species from different families (Coleoptera: Staphylinidae: Aleochara curtula; Silphidae: Nicrophorus vespilloides; Tenebrionidae: Blaps lethifera) to obtain detailed information on parentage in mating systems. We report variations in the number of hybridizing fragments for the different species depending on the combinations of probes and restriction enzymes used. In addition to conventional multilocus fingerprint patterns, we established a single locus system for A. curtula (GTG5; HinfI) and described an oligolocus system in N. vespilloides (GATA4; HaeIII).


Asunto(s)
Escarabajos/genética , Dermatoglifia del ADN/métodos , Tenebrio/genética , Animales , Mapeo Cromosómico , Electroforesis en Gel de Agar , Femenino , Variación Genética , Masculino , Oligonucleótidos , Especificidad de la Especie
9.
Zentralbl Gynakol ; 112(4): 215-21, 1990.
Artículo en Alemán | MEDLINE | ID: mdl-2336894

RESUMEN

Based on a multicentric prospective study 727 cases of caesarean section (C.S.) in 13 departments of gynecology and obstetrics in 1987 will be examined by means of computer aided analysis. The rate of C.S. was between 6.5% and 13.4% in the obstetrical centres, and between 2.6% and 6.7% in the general district hospitals. There isn't a defined correlation between the rate of C.S. and perinatal mortality in one department. The increased C.S. rate of the centres is based on more neonatological indications like prematurity, perinatal infection risk and traumatic hazard. Perinatal mortality and C.S. rate are only comparable under consideration with all cases of deliveries especially with frequency of obstetrical high risk cases in a department. The high C.S. rate of first obstetrical centre in comparison with the second one is connected with reducing of perinatal mortality of newborn delivered by C.S. to about the half. Therefore we suggest the caesarean section-index of perinetal mortality. It is the relation between perinatal mortality of newborn delivered by C.S. and the total perinatal mortality.


Asunto(s)
Cesárea/estadística & datos numéricos , Enfermedades del Prematuro/mortalidad , Estudios Transversales , Femenino , Alemania Oriental/epidemiología , Humanos , Incidencia , Recién Nacido , Embarazo , Estudios Prospectivos , Factores de Riesgo
10.
J Comp Physiol A ; 161(3): 377-88, 1987 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3668879

RESUMEN

The primary components of the defensive secretions of Blaps mucronata (Tenebrionidae) are two quinones (methyl-p-benzoquinone and ethyl-p-benzoquinone) and the hydrocarbon 1-n-tridecene. The hydrocarbon is shown, by comparison with longer- and shorter-chain n-alkanes and 1-n-alkenes, to be optimally suited as carrier of the quinones, and as a surfactant that promotes spread of secretion over the beetle's body following discharge from the gland openings at the abdominal tip. As shown from repellency tests with ants (Monomorium pharaonis) and topical irritancy tests with cockroaches (Periplaneta americana), the anti-insectan potency of the secretion derives as much from the hydrocarbon as from the quinones.


Asunto(s)
Benzoquinonas , Escarabajos/fisiología , Insecticidas/metabolismo , Animales , Femenino , Hidrocarburos/metabolismo , Insecticidas/aislamiento & purificación , Masculino , Quinonas/metabolismo
11.
J Chem Ecol ; 13(10): 1993-2008, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24301470

RESUMEN

Immature, starved, or multiply mated males of the staphylinid beetle,Aleochara curtula, mimic their females chemically. The titer of the female sex pheromone components (Z)-7-heneicosene and (Z)-7-tricosene was quantified for various physiological types and both sexes by gas chromatography and correlated with the sexual response of males towards the cuticular hydrocarbon fractions. Modulation of intermale aggression by production of the female pheromone was shown by (1) reduction of the alkene titer of females kept at elevated temperatures, (2) treating live males with the synthetic female pheromone mixture, and (3) gradual amputation of male antennal segments.A. curtula males do not fight against members of otherAleochara species with a different hydrocarbon pattern. Contamination ofA. peschkei males with the hydrocarbon fraction ofA. curtula males, however, provoked the release of aggression. Choosy females reject mating attempts of males bearing the female sex pheromone.

12.
Zentralbl Gynakol ; 108(3): 163-6, 1986.
Artículo en Alemán | MEDLINE | ID: mdl-3457500

RESUMEN

The influence of prophylactic treatment with metronidazole on infectious morbity after induced abortion by intermittent intrauterine extraamniotic application of PGF2 alpha was studied in 255 primigravidae. The rate of inflammatory complications was decreased significantly by oral and rectal application of Vagimid.


Asunto(s)
Aborto Inducido , Metronidazol/uso terapéutico , Prostaglandinas F , Infección de la Herida Quirúrgica/prevención & control , Adolescente , Adulto , Dinoprost , Endometritis/prevención & control , Femenino , Humanos , Enfermedad Inflamatoria Pélvica/prevención & control , Embarazo , Salpingitis/prevención & control
14.
J Chem Ecol ; 9(1): 13-31, 1983 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24408616

RESUMEN

At high concentrations, the defensive tergal gland secretion (TGS)(3) of the staphylinid beetle,Aleochara curtula, inhibits the male copulatory response (grasping with parameres). Inhibitory chemicals, for which a function as alarm substances is assumed, aren-undecane, 1-undecene,n-dodecanal, toluquinone, and 2-methoxy-3-methyl-1,4-benzoquinone. When emitted in small amounts, however, the TGS releases the male grasping response. The main components with aphrodisiac effect are (Z)-4-tridecene,n-dodecanal, and (Z)-5-tetradecenal. These supplementary mating stimulants, which are not sex specific, work synergistically with the aphrodisiac female sex pheromone from thé epicuticular lipids and are discussed as alerting pheromones of short-term effect. Antennal movements of resting males as an indication of the recognition of a female and the approach to the mate are released at somewhat longer distances, when the TGS is additionally present.

15.
J Chem Ecol ; 8(4): 773-83, 1982 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24415124

RESUMEN

The defensive secretion from the tergal gland of the staphylinid beetle,Aleochara curtula, acting as a supplementary mating stimulant, was investigated by gas-liquid chromatography, mass spectrometry, and IR spectroscopy. The reservoir contains a complex mixture of hydrocarbons, aliphatic aldehydes, and substituted 1,4-benzoquinones.n-Undecane, 1-undecene, and (Z)-4-tridecene were identified as the major hydrocarbon components. The main aldehydes aren-dodecanal and (Z)-5-tetradecenal, and the chief quinones are toluquinone and 2-methoxy-3-methyl-1,4-benzoquinone, the latter being established structurally by comparison of the mass spectra of the three synthesized isomers. Quantitative GLC analyses revealed no sex specificity of the relative concentrations of the compounds.

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