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1.
Cell Biol Int ; 47(6): 1136-1146, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36906806

ABSTRACT

Inflammation in the established tumor microenvironment (TME) is often associated with a poor prognosis of breast cancer. Bisphenol A (BPA) is an endocrine-disrupting chemical that acts as inflammatory promoter and tumoral facilitator in mammary tissue. Previous studies demonstrated the onset of mammary carcinogenesis at aging when BPA exposure occurred in windows of development/susceptibility. We aim to investigate the inflammatory repercussions of BPA in TME in mammary gland (MG) during neoplastic development in aging. Female Mongolian gerbils were exposed to low (50 µg/kg) or high BPA (5000 µg/kg) doses during pregnancy and lactation. They were euthanized at 18 months of age (aging) and the MG were collected for inflammatory markers and histopathological analysis. Contrarily to control MG, BPA induced carcinogenic development mediated by COX-2 and p-STAT3 expression. BPA was also able to promote macrophage and mast cell (MC) polarization in tumoral phenotype, evidenced by pathways for recruitment and activation of these inflammatory cells and tissue invasiveness triggered by tumor necrosis factor-alpha and transforming growth factor-beta 1 (TGF-ß1). Increase of tumor-associated macrophages, M1 (CD68 + iNOS+) and M2 (CD163+) expressing pro-tumoral mediators and metalloproteases was observed; this aspect greatly contributed to stromal remodeling and invasion of neoplastic cells. In addition, the MC population drastically increased in BPA-exposed MG. Tryptase-positive MCs increased in disrupted MG and expressed TGF-ß1, contributing to EMT process during carcinogenesis mediated by BPA. BPA exposure interfered in inflammatory response by releasing and enhancing the expression of mediators that contribute to tumor growth and recruitment of inflammatory cells that promote a malignant profile.


Subject(s)
Transforming Growth Factor beta1 , Tumor Microenvironment , Pregnancy , Female , Humans , Benzhydryl Compounds , Carcinogenesis , Phenotype
2.
Mol Ecol ; 31(22): 5795-5812, 2022 11.
Article in English | MEDLINE | ID: mdl-36161402

ABSTRACT

Climate change will strongly affect the developmental timing of insects, as their development rate depends largely on ambient temperature. However, we know little about the genetic mechanisms underlying the temperature sensitivity of embryonic development in insects. We investigated embryonic development rate in the winter moth (Operophtera brumata), a species with egg dormancy which has been under selection due to climate change. We used RNA sequencing to investigate which genes are involved in the regulation of winter moth embryonic development rate in response to temperature. Over the course of development, we sampled eggs before and after an experimental change in ambient temperature, including two early development weeks when the temperature sensitivity of eggs is low and two late development weeks when temperature sensitivity is high. We found temperature-responsive genes that responded in a similar way across development, as well as genes with a temperature response specific to a particular development week. Moreover, we identified genes whose temperature effect size changed around the switch in temperature sensitivity of development rate. Interesting candidate genes for regulating the temperature sensitivity of egg development rate included genes involved in histone modification, hormonal signalling, nervous system development and circadian clock genes. The diverse sets of temperature-responsive genes we found here indicate that there are many potential targets of selection to change the temperature sensitivity of embryonic development rate. Identifying for which of these genes there is genetic variation in wild insect populations will give insight into their adaptive potential in the face of climate change.


Subject(s)
Circadian Clocks , Moths , Animals , Moths/genetics , Temperature , Seasons , Circadian Clocks/genetics , Insecta , Embryonic Development/genetics
3.
Polymers (Basel) ; 13(7)2021 Mar 26.
Article in English | MEDLINE | ID: mdl-33810345

ABSTRACT

Ternary blends of polylactide (PLA, 90 wt.%) and poly(methyl methacrylate) (PMMA, 10 wt.%) with functionalized polysilsesquioxanes (LPSQ-R) were obtained by solution blending. R groups in LPSQ containing hydroxyethyl (LPSQ-OH), methylglycolic (LPSQ-COOMe) and pentafluorophenyl (LPSQ-F5) moieties of different chemical properties were designed to modify PLA blends with PMMA. The effect of the type of LPSQ-R and their content, 1-3 wt.%, on the structure of the blends was studied with scanning electron microscopy (SEM) combined with energy dispersive spectroscopy (SEM-EDS), dynamic mechanical thermal analysis (DMTA) and Raman spectroscopy. Differential scanning calorimetry (DSC) and tensile tests also showed various effects of LPSQ-R on the thermal and mechanical properties of the blends. Depth-sensing indentation was used to resolve spatially the micro- and nano-scale mechanical properties (hardness and elastic behaviour) of the blends. The results showed clearly that LPSQ-R modulate the structure and properties of the blends.

4.
Cell Biol Int ; 44(6): 1341-1352, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32100915

ABSTRACT

The development and maintenance of prostate function depend on a fine balance between oestrogen and androgen levels. Finasteride inhibits 5α-reductase, which is responsible for the conversion of testosterone into its most active form, dihydrotestosterone. Enzymes that metabolize these hormones have a highly relevant role in both the normal prostate metabolism and in the occurrence of pathological conditions. There are few studies on the impact of finasteride on male prostate development and fewer studies on the female prostate and possible intersexual differences. Therefore, we treated male and female gerbils from 7 to 14 days in postnatal life with a high dose of finasteride (500 µg/kg/day); the prostate complexes were then removed and submitted to immunohistochemistry, immunofluorescence and three-dimensional reconstruction. In addition, hormonal serum dosages were administered. Treatment with finasteride resulted in an increased thickness of the periductal smooth musculature in the prostate of both male and female gerbils, such as well as a reduction in the thickness of developing prostate alveoli in both sexes. In addition, intersexual differences were observed as increased epithelial proliferation and decreases in the number of developing alveoli in females. Together, the data indicate that postnatal exposure to finasteride causes greater changes in the female gerbil prostate than in the male.


Subject(s)
Finasteride/toxicity , Gerbillinae/growth & development , Prostate , Animals , Female , Male , Prostate/drug effects , Prostate/growth & development , Receptors, Androgen/metabolism , Testosterone/blood
5.
Reprod Fertil Dev ; 31(11): 1719-1729, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31248476

ABSTRACT

Finasteride is a drug that is widely used in the treatment of benign prostatic hyperplasia, hair loss and even as a chemotherapeutic agent in the treatment of prostatic adenocarcinoma. However, its use is known to cause several side effects in adults and it can also cause changes in the embryonic development of the male prostate, which is a cause for concern given the possibility of the accumulation of finasteride in the environment. Nevertheless, no studies have investigated the effects of finasteride on the development of the prostate in females, which occurs in several species of mammals. To evaluate the effects of intrauterine exposure to finasteride (500µgkg-1 day-1) on postnatal prostate development in the Mongolian gerbil in the present study, we used immunohistochemistry, immunofluorescence, serological analysis and three-dimensional reconstruction techniques. Differences were observed in the effects of finasteride on periductal smooth muscle and cell proliferation between the sexes, as well as intersex differences in the presence of the androgen receptor, which was elevated in males, and the oestrogen receptor ERα, which was increased in females. Together, the data indicate that the female prostate has its own hormone dynamics and that there are sex-specific differences in the way in which the female prostate reacts to prenatal exposure to finasteride.


Subject(s)
Finasteride/pharmacology , Gerbillinae/growth & development , Prenatal Exposure Delayed Effects , Prostate/drug effects , Prostate/growth & development , Animals , Female , Immunohistochemistry , Male , Organogenesis/drug effects , Pregnancy , Prenatal Exposure Delayed Effects/chemically induced , Prenatal Exposure Delayed Effects/metabolism , Prenatal Exposure Delayed Effects/physiopathology , Prenatal Exposure Delayed Effects/veterinary , Prostate/metabolism , Receptors, Androgen/drug effects , Receptors, Androgen/metabolism , Receptors, Estrogen/drug effects , Receptors, Estrogen/metabolism , Sex Characteristics
6.
Int J Mol Sci ; 20(8)2019 Apr 24.
Article in English | MEDLINE | ID: mdl-31022884

ABSTRACT

Antibiofilm strategies may be based on the prevention of initial bacterial adhesion, the inhibition of biofilm maturation or biofilm eradication. N-acetyl-L-cysteine (NAC), widely used in medical treatments, offers an interesting approach to biofilm destruction. However, many Eubacteria strains are able to enzymatically decompose the NAC molecule. This is the first report on the action of two hybrid materials, NAC-Si-1 and NAC-Si-2, against bacteria isolated from a water environment: Agrobacterium tumefaciens, Aeromonas hydrophila, Citrobacter freundii, Enterobacter soli, Janthinobacterium lividum and Stenotrophomonas maltophilia. The NAC was grafted onto functional siloxane polymers to reduce its availability to bacterial enzymes. The results confirm the bioactivity of NAC. However, the final effect of its action was environment- and strain-dependent. Moreover, all the tested bacterial strains showed the ability to degrade NAC by various metabolic routes. The NAC polymers were less effective bacterial inhibitors than NAC, but more effective at eradicating mature bacterial biofilms.


Subject(s)
Acetylcysteine/pharmacology , Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Biofilms/drug effects , Drinking Water/microbiology , Siloxanes/pharmacology , Acetylcysteine/chemistry , Anti-Bacterial Agents/chemistry , Bacterial Adhesion/drug effects , Siloxanes/chemistry , Water Purification
7.
Front Microbiol ; 9: 674, 2018.
Article in English | MEDLINE | ID: mdl-29692763

ABSTRACT

Organic vinasse, a residue produced during bioethanol production, increases nitrous oxide (N2O) emissions when applied with inorganic nitrogen (N) fertilizer in soil. The present study investigated the role of the ammonia-oxidizing bacteria (AOB) community on the N2O emissions in soils amended with organic vinasse (CV: concentrated and V: non-concentrated) plus inorganic N fertilizer. Soil samples and N2O emissions were evaluated at 11, 19, and 45 days after fertilizer application, and the bacterial and archaea gene (amoA) encoding the ammonia monooxygenase enzyme, bacterial denitrifier (nirK, nirS, and nosZ) genes and total bacteria were quantified by real time PCR. We also employed a deep amoA amplicon sequencing approach to evaluate the effect of treatment on the community structure and diversity of the soil AOB community. Both vinasse types applied with inorganic N application increased the total N2O emissions and the abundance of AOB. Nitrosospira sp. was the dominant AOB in the soil and was correlated with N2O emissions. However, the diversity and the community structure of AOB did not change with vinasse and inorganic N fertilizer amendment. The results highlight the importance of residues and fertilizer management in sustainable agriculture and can be used as a reference and an input tool to determine good management practices for organic fertilization.

9.
Oecologia ; 186(1): 85-97, 2018 01.
Article in English | MEDLINE | ID: mdl-29063200

ABSTRACT

Sex- and age-dependence in recruitment and dispersal are often explained by costs arising from competition for holding a breeding territory over the years-a typical feature of species living in stable habitats. For instance, long-lived birds with male territoriality often exhibit large variation in recruitment age and higher dispersal in females and young individuals. As a corollary, we expected that species with ephemeral habitat suitability, and hence nomadic breeding, would show weak age- and sex-dependence in dispersal and low variation in recruitment age, because territory ownership is not maintained over the years. In addition, the higher cost of reproduction in females might not be (over)compensated for by costs of territoriality in males. Accordingly, females would recruit later than males. We explored these variations using multievent capture-recapture models over 13 years, 3479 (2392 sexed) slender-billed gulls (Chroicocephalus genei) and 45 colony sites along the French Mediterranean coast. As expected, variability in recruitment age was low with males recruiting earlier than females. Nonetheless, dispersal in and out of the study area decreased with age and was slightly higher in males than in females. Decreased dispersal with age might result from foraging benefits associated with increased spatial familiarity. Higher dispersal in males might be explained by a male-biased sex ratio or higher philopatry benefits in females (arising from their higher cost of reproduction). Sex- and age-dependent dispersal and recruitment may thus occur in the absence of year-to-year breeding territory ownership, which stresses the importance of considering other processes in shaping recruitment and dispersal patterns.


Subject(s)
Birds , Reproduction , Animals , Breeding , Ecosystem , Female , Male , Sex Ratio
10.
Genome Biol Evol ; 7(8): 2321-32, 2015 Jul 29.
Article in English | MEDLINE | ID: mdl-26227816

ABSTRACT

The winter moth (Operophtera brumata) belongs to one of the most species-rich families in Lepidoptera, the Geometridae (approximately 23,000 species). This family is of great economic importance as most species are herbivorous and capable of defoliating trees. Genome assembly of the winter moth allows the study of genes and gene families, such as the cytochrome P450 gene family, which is known to be vital in plant secondary metabolite detoxification and host-plant selection. It also enables exploration of the genomic basis for female brachyptery (wing reduction), a feature of sexual dimorphism in winter moth, and for seasonal timing, a trait extensively studied in this species. Here we present a reference genome for the winter moth, the first geometrid and largest sequenced Lepidopteran genome to date (638 Mb) including a set of 16,912 predicted protein-coding genes. This allowed us to assess the dynamics of evolution on a genome-wide scale using the P450 gene family. We also identified an expanded gene family potentially linked to female brachyptery, and annotated the genes involved in the circadian clock mechanism as main candidates for involvement in seasonal timing. The genome will contribute to Lepidopteran genomic resources and comparative genomics. In addition, the genome enhances our ability to understand the genetic and molecular basis of insect seasonal timing and thereby provides a reference for future evolutionary and population studies on the winter moth.


Subject(s)
Genome, Insect , Moths/genetics , Sex Characteristics , Animals , Circadian Clocks/genetics , Cytochrome P-450 Enzyme System/genetics , Genomics , Humans , Male , Molecular Sequence Data , Moths/anatomy & histology , Seasons
11.
Analyst ; 140(9): 3113-20, 2015 May 07.
Article in English | MEDLINE | ID: mdl-25751126

ABSTRACT

Curcumin is a versatile anti-inflammatory and anti-cancer agent known for its low bioavailability, which could be improved by developing materials capable of binding and releasing drug in a controlled fashion. The present study describes the preparation of magnetic nano-sized Molecularly Imprinted Polymers (nanoMIPs) for the controlled delivery of curcumin and their high throughput characterisation using microtitre plates modified with magnetic inserts. NanoMIPs were synthesised using functional monomers chosen with the aid of molecular modelling. The rate of release of curcumin from five polymers was studied under aqueous conditions and was found to correlate well with the binding energies obtained computationally. The presence of specific monomers was shown to be significant in ensuring effective binding of curcumin and to the rate of release obtained. Characterisation of the polymer particles was carried out using dynamic light scattering (DLS) technique and scanning electron microscopy (SEM) in order to establish the relationship between irradiation time and particle size. The protocols optimised during this study could be used as a blueprint for the development of nanoMIPs capable of the controlled release of potentially any compound of interest.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Antineoplastic Agents/administration & dosage , Curcumin/administration & dosage , Delayed-Action Preparations/chemistry , Magnets/chemistry , Molecular Imprinting/methods , Polymers/chemistry , Humans
12.
Glob Chang Biol ; 19(2): 621-36, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23504797

ABSTRACT

Carbon (C) uptake by terrestrial ecosystems represents an important option for partially mitigating anthropogenic CO2 emissions. Short-term atmospheric elevated CO2 exposure has been shown to create major shifts in C flow routes and diversity of the active soil-borne microbial community. Long-term increases in CO2 have been hypothesized to have subtle effects due to the potential adaptation of soil microorganism to the increased flow of organic C. Here, we studied the effects of prolonged elevated atmospheric CO2 exposure on microbial C flow and microbial communities in the rhizosphere. Carex arenaria (a nonmycorrhizal plant species) and Festuca rubra (a mycorrhizal plant species) were grown at defined atmospheric conditions differing in CO2 concentration (350 and 700 ppm) for 3 years. During this period, C flow was assessed repeatedly (after 6 months, 1, 2, and 3 years) by (13) C pulse-chase experiments, and label was tracked through the rhizosphere bacterial, general fungal, and arbuscular mycorrhizal fungal (AMF) communities. Fatty acid biomarker analyses and RNA-stable isotope probing (RNA-SIP), in combination with real-time PCR and PCR-DGGE, were used to examine microbial community dynamics and abundance. Throughout the experiment the influence of elevated CO2 was highly plant dependent, with the mycorrhizal plant exerting a greater influence on both bacterial and fungal communities. Biomarker data confirmed that rhizodeposited C was first processed by AMF and subsequently transferred to bacterial and fungal communities in the rhizosphere soil. Over the course of 3 years, elevated CO2 caused a continuous increase in the (13) C enrichment retained in AMF and an increasing delay in the transfer of C to the bacterial community. These results show that, not only do elevated atmospheric CO2 conditions induce changes in rhizosphere C flow and dynamics but also continue to develop over multiple seasons, thereby affecting terrestrial ecosystems C utilization processes.


Subject(s)
Atmosphere , Carbon Dioxide/analysis , Carbon/chemistry , Microbiology , Biomarkers/analysis , Biomass , Carbon Isotopes/analysis , Plants/microbiology
13.
FEMS Microbiol Ecol ; 83(3): 607-21, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23013447

ABSTRACT

This study focused on the impact of land-use changes and agricultural management of soybean in Amazon forest soils on the abundance and composition of the acidobacterial community. Quantitative real-time PCR (q-PCR) assays and pyrosequencing of 16S rRNA gene were applied to study the acidobacterial community in bulk soil samples from soybean croplands and adjacent native forests, and mesocosm soil samples from soybean rhizosphere. Based on qPCR measurements, Acidobacteria accounted for 23% in forest soils, 18% in cropland soils, and 14% in soybean rhizosphere of the total bacterial signals. From the 16S rRNA gene sequences of Bacteria domain, the phylum Acidobacteria represented 28% of the sequences from forest soils, 16% from cropland soils, and 17% from soybean rhizosphere. Acidobacteria subgroups 1-8, 10, 11, 13, 17, 18, 22, and 25 were detected with subgroup 1 as dominant among them. Subgroups 4, 6, and 7 were significantly higher in cropland soils than in forest soils, which subgroups responded to decrease in soil aluminum. Subgroups 6 and 7 responded to high content of soil Ca, Mg, Mn, and B. These results showed a differential response of the Acidobacteria subgroups to abiotic soil factors, and open the possibilities to explore acidobacterial subgroups as early-warning bioindicators of agricultural soil management effects in the Amazon area.


Subject(s)
Acidobacteria/growth & development , Agriculture/methods , Glycine max/microbiology , Rhizosphere , Soil Microbiology , Acidobacteria/genetics , Brazil , DNA, Bacterial/isolation & purification , Phylogeny , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Soil/analysis , Trees/microbiology
14.
PLoS One ; 7(2): e30600, 2012.
Article in English | MEDLINE | ID: mdl-22355318

ABSTRACT

BACKGROUND: The 16S rRNA gene is the gold standard in molecular surveys of bacterial and archaeal diversity, but it has the disadvantages that it is often multiple-copy, has little resolution below the species level and cannot be readily interpreted in an evolutionary framework. We compared the 16S rRNA marker with the single-copy, protein-coding rpoB marker by amplifying and sequencing both from a single soil sample. Because the higher genetic resolution of the rpoB gene prohibits its use as a universal marker, we employed consensus-degenerate primers targeting the Proteobacteria. METHODOLOGY/PRINCIPAL FINDINGS: Pyrosequencing can be problematic because of the poor resolution of homopolymer runs. As these erroneous runs disrupt the reading frame of protein-coding sequences, removal of sequences containing nonsense mutations was found to be a valuable filter in addition to flowgram-based denoising. Although both markers gave similar estimates of total diversity, the rpoB marker revealed more species, requiring an order of magnitude fewer reads to obtain 90% of the true diversity. The application of population genetic methods was demonstrated on a particularly abundant sequence cluster. CONCLUSIONS/SIGNIFICANCE: The rpoB marker can be a complement to the 16S rRNA marker for high throughput microbial diversity studies focusing on specific taxonomic groups. Additional error filtering is possible and tests for recombination or selection can be employed.


Subject(s)
DNA, Bacterial/genetics , Genetic Markers , Genetic Variation , Proteobacteria/classification , Proteobacteria/genetics , RNA Polymerase II/genetics , RNA, Ribosomal, 16S/genetics , Phylogeny , Sequence Analysis, DNA
15.
FEMS Microbiol Ecol ; 79(1): 12-24, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22066695

ABSTRACT

To gain insight into the factors driving the structure of bacterial communities in soil, we applied real-time PCR, PCR-denaturing gradient gel electrophoreses, and phylogenetic microarray approaches targeting the 16S rRNA gene across a range of different land usages in the Netherlands. We observed that the main differences in the bacterial communities were not related to land-use type, but rather to soil factors. An exception was the bacterial community of pine forest soils (PFS), which was clearly different from all other sites. PFS had lowest bacterial abundance, lowest numbers of operational taxonomic units (OTUs), lowest soil pH, and highest C : N ratios. C : N ratio strongly influenced bacterial community structure and was the main factor separating PFS from other fields. For the sites other than PFS, phosphate was the most important factor explaining the differences in bacterial communities across fields. Firmicutes were the most dominant group in almost all fields, except in PFS and deciduous forest soils (DFS). In PFS, Alphaproteobacteria was most represented, while in DFS, Firmicutes and Gammaproteobacteria were both highly represented. Interestingly, Bacillii and Clostridium OTUs correlated with pH and phosphate, which might explain their high abundance across many of the Dutch soils. Numerous bacterial groups were highly correlated with specific soil factors, suggesting that they might be useful as indicators of soil status.


Subject(s)
Bacteria/classification , Soil Microbiology , Soil/chemistry , Alphaproteobacteria/classification , Alphaproteobacteria/genetics , Alphaproteobacteria/growth & development , Bacteria/genetics , Bacteria/growth & development , Biodiversity , DNA, Bacterial/analysis , Denaturing Gradient Gel Electrophoresis , Gammaproteobacteria/classification , Gammaproteobacteria/genetics , Gammaproteobacteria/growth & development , Netherlands , Phylogeny , RNA, Ribosomal, 16S/genetics , Real-Time Polymerase Chain Reaction , Sequence Analysis, DNA
16.
Proc Natl Acad Sci U S A ; 107(24): 10938-42, 2010 Jun 15.
Article in English | MEDLINE | ID: mdl-20534474

ABSTRACT

Rising atmospheric CO(2) levels are predicted to have major consequences on carbon cycling and the functioning of terrestrial ecosystems. Increased photosynthetic activity is expected, especially for C-3 plants, thereby influencing vegetation dynamics; however, little is known about the path of fixed carbon into soil-borne communities and resulting feedbacks on ecosystem function. Here, we examine how arbuscular mycorrhizal fungi (AMF) act as a major conduit in the transfer of carbon between plants and soil and how elevated atmospheric CO(2) modulates the belowground translocation pathway of plant-fixed carbon. Shifts in active AMF species under elevated atmospheric CO(2) conditions are coupled to changes within active rhizosphere bacterial and fungal communities. Thus, as opposed to simply increasing the activity of soil-borne microbes through enhanced rhizodeposition, elevated atmospheric CO(2) clearly evokes the emergence of distinct opportunistic plant-associated microbial communities. Analyses involving RNA-based stable isotope probing, neutral/phosphate lipid fatty acids stable isotope probing, community fingerprinting, and real-time PCR allowed us to trace plant-fixed carbon to the affected soil-borne microorganisms. Based on our data, we present a conceptual model in which plant-assimilated carbon is rapidly transferred to AMF, followed by a slower release from AMF to the bacterial and fungal populations well-adapted to the prevailing (myco-)rhizosphere conditions. This model provides a general framework for reappraising carbon-flow paths in soils, facilitating predictions of future interactions between rising atmospheric CO(2) concentrations and terrestrial ecosystems.


Subject(s)
Carbon Dioxide/metabolism , Carbon/metabolism , Ecosystem , Plant Roots/metabolism , Plant Roots/microbiology , Atmosphere/chemistry , Bacteria/genetics , Bacteria/metabolism , Carbon Isotopes/metabolism , Carex Plant/metabolism , Carex Plant/microbiology , Climate Change , Festuca/metabolism , Festuca/microbiology , Fungi/genetics , Fungi/metabolism , Models, Biological , Molecular Sequence Data , Mycorrhizae/metabolism , RNA, Bacterial/genetics , RNA, Fungal/genetics , Soil/analysis , Soil Microbiology
17.
ISME J ; 3(3): 378-82, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19020558

ABSTRACT

Although Acidobacteria represent the most abundant bacterial phylum in many soils, knowledge of acidobacterial diversity is still rather incomplete. We, therefore, examined the diversity of 16S rRNA genes affiliated with this phylum in a former arable soil via three independent approaches: (1) screening of a fosmid metagenome library for inserts containing Acidobacteria-like 16S rRNA genes; (2) PCR-cloning using general bacterial primers; and (3) PCR-cloning with acidobacterial-specific primers. Bacterial-specific libraries compared rhizosphere versus bulk soil samples, revealing a higher proportion of acidobacterial sequences in bulk soil libraries (P<0.001). Bacterial libraries recovered the greatest diversity, and sequence examination suggested that sequence mismatches with the Acidobacteria-specific primers limited the coverage of the metagenome library screening and specific library approaches. Together, these results expand knowledge of the distribution and diversity of Acidobacteria in soil environments and highlight important technical considerations in the molecular analysis of Acidobacteria diversity.


Subject(s)
Bacteria/classification , Bacteria/isolation & purification , Biodiversity , Soil Microbiology , Cloning, Molecular , DNA Primers/genetics , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Gene Library , Genes, rRNA , Molecular Sequence Data , Phylogeny , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Sequence Homology, Nucleic Acid
18.
FEMS Microbiol Ecol ; 63(3): 372-82, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18205817

ABSTRACT

To examine the relationship between plant species composition and microbial community diversity and structure, we carried out a molecular analysis of microbial community structure and diversity in two field experiments. In the first experiment, we examined bacterial community structure in bulk and rhizosphere soils in fields exposed to different plant diversity treatments, via a 16S rRNA gene clone library approach. Clear differences were observed between bacterial communities of the bulk soil and the rhizosphere, with the latter containing lower bacterial diversity. The second experiment focused on the influence of 12 different native grassland plant species on bacterial community size and structure in the rhizosphere, as well as the structure of Acidobacteria and Verrucomicrobia community structures. In general, bacterial and phylum-specific quantitative PCR and PCR-denaturing gradient gel electrophoresis revealed only weak influences of plant species on rhizosphere communities. Thus, although plants did exert an influence on microbial species composition and diversity, these interactions were not specific and selective enough to lead to major impacts of vegetation composition and plant species on below-ground microbial communities.


Subject(s)
Bacteria/classification , Magnoliopsida/classification , Magnoliopsida/growth & development , Soil Microbiology , Agriculture , Asteraceae/growth & development , Bacteria/genetics , Biodiversity , DNA, Bacterial/analysis , Ecosystem , Electrophoresis/methods , Lotus/growth & development , Molecular Sequence Data , Plant Roots/microbiology , Poaceae/growth & development , Polymerase Chain Reaction , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
19.
J Med Genet ; 42(10): e64, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16199546

ABSTRACT

BACKGROUND: BRCA1 and BRCA2 are the two major genes responsible for the breast and ovarian cancers that cluster in families with a genetically determined predisposition. However, regardless of the mutation detection method employed, the percentage of families without identifiable alterations of these genes exceeds 50%, even when applying stringent criteria for family selection. A small but significant increase in mutation detection rate has resulted from the discovery of large genomic alterations in BRCA1. A few studies have addressed the question of whether BRCA2 might be inactivated by the same kinds of alteration, but most were either done on a relatively small number of samples or employed cumbersome mutation detection methods of variable sensitivity. OBJECTIVE: To analyse 121 highly selected families using the recently available BRCA2 multiplex ligation dependent probe amplification (MLPA) technique. RESULTS: Three different large genomic deletions were identified and confirmed by analysis of the mutant transcript and genomic characterisation of the breakpoints. CONCLUSIONS: Contrary to initial suggestions, the presence of BRCA2 genomic rearrangements is worth investigating in high risk breast or ovarian cancer families.


Subject(s)
BRCA2 Protein/genetics , Breast Neoplasms/genetics , Gene Deletion , Genetic Testing/methods , Genome , Breast Neoplasms/metabolism , Cloning, Molecular , DNA Mutational Analysis , Exons , Female , Genetic Predisposition to Disease , Humans , Models, Genetic , Molecular Sequence Data , Recombination, Genetic
20.
Int J Gynecol Cancer ; 15(5): 817-23, 2005.
Article in English | MEDLINE | ID: mdl-16174230

ABSTRACT

The aim of our study was to generate predictive model, which would allow to estimate the influence of analyzed parameters on predictive accuracy of differential diagnosis of adnexal masses and to evaluate prospectively diagnostic efficacy of the statistic model in the new set of patients. A total of 686 women diagnosed and surgically treated in the Gynecological and Obstetrical Teaching Hospital of University of Medical Sciences in Poznan, Poland, were recruited into the study. Preoperative diagnostics included gynecological examination, ultrasonographic evaluation, tumor Doppler blood flow analysis, and serum levels of CA125 and TPS. In order to find the best combination of features and to calculate the individual probability of the malignancy, stepwise logistic regression analysis with quasi-Newton estimation was applied. The essential part of the best prognostic model, described by foregoing variables, is as follows: [z = -6.005 + 0.058 x age + 1.174 x septa + 1.317 x tumor localization + 1.185 x ascites + 2.28 x solid element + 2.429 x vessels localization -2.386 x PI + 0.084 x MEDV]. The highest sensitivity and specificity for the obtained model were 87.84% and 93.74%, respectively. Prognostic model, constructed with the use of logistic regression analysis, is characterized by higher sensitivity and specificity than individually applied diagnostic tests. Prospective evaluation of this model application in a larger group of patients with adnexal masses will enable precise assessment of its objective clinical usefulness.


Subject(s)
Adnexal Diseases/diagnosis , Adnexal Diseases/classification , Adolescent , Adult , Aged , Aged, 80 and over , Child , Diagnosis, Differential , Female , Humans , Logistic Models , Middle Aged , Neoplasm Staging , Prognosis
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