RESUMO
Biodiversity loss is mainly driven by human activity. While concern grows over the fate of hot spots of biodiversity, contemporary species losses still prevail in industrialized nations. Therefore, strategies were formulated to halt or reverse the loss, driven by evidence for its value for ecosystem services. Maintenance of the latter through conservation depends on correctly identified species. To this aim, the German Federal Ministry of Education and Research is funding the GBOL project, a consortium of natural history collections, botanic gardens, and universities working on a barcode reference database for the country's fauna and flora. Several noticeable findings could be useful for future campaigns: (i) validating taxon lists to serve as a taxonomic backbone is time-consuming, but without alternative; (ii) offering financial incentives to taxonomic experts, often citizen scientists, is indispensable; (iii) completion of the libraries for widespread species enables analyses of environmental samples, but the process may not hold pace with technological advancements; (iv) discoveries of new species are among the best stories for the media; (v) a commitment to common data standards and repositories is needed, as well as transboundary cooperation between nations; (vi) after validation, all data should be published online via the BOLD to make them searchable for external users and to allow cross-checking with data from other countries.
Assuntos
Biodiversidade , Código de Barras de DNA Taxonômico , Bases de Dados Genéticas , Animais , Países Desenvolvidos , Alemanha , Fidelidade a Diretrizes , Humanos , Cooperação Internacional , Bibliotecas , Reprodutibilidade dos TestesRESUMO
Superhalogens belong to a class of molecules that not only mimic the chemistry of halogen atoms but also possess electron affinities that are much larger than that of chlorine, the element with the highest electron affinity in the periodic table. Using BO2 as an example and the synergy between density functional theory-based calculations and photoelectron spectroscopy experiments we demonstrate another unusual property of superhalogens. Unlike halogens, whose ability to accept an electron falls upon dimerization, B2O4, the dimer of BO2, has an electron affinity larger than that of the BO2 building block. This ability of (BO2)2 and subsequent, higher oligomers (BO2)n (n = 3 and 4), to retain their superhalogen characteristics can be traced to the enhanced bonding interactions between oxygen and boron atoms and due to the delocalization of the charge of the extra-electron over the terminal oxygen atoms. These results open the door to the design and synthesis of a new class of metal-free highly negative ions with potential for novel applications.
Assuntos
Compostos de Boro/química , Halogênios/química , Elétrons , Espectroscopia Fotoeletrônica , Teoria QuânticaAssuntos
Dor Abdominal/etiologia , Carcinoma Papilar/diagnóstico , Erros de Diagnóstico/prevenção & controle , Imageamento por Ressonância Magnética/métodos , Neoplasias Pancreáticas/diagnóstico , Dor Abdominal/diagnóstico , Adulto , Carcinoma Papilar/complicações , Diagnóstico Diferencial , Feminino , Humanos , Neoplasias Pancreáticas/complicaçõesRESUMO
BACKGROUND: Currently, absorbable meshes are used as temporary closure in case of laparostoma. Unfortunately the multifilament polyglycolic acid (PG) meshes with small pores reveal little elasticity acting rather as a fluid barrier than permitting drainage of intra-abdominal fluids. Therefore, a new mesh was constructed of absorbable polydioxanon monofilaments (PDS) with increased porosity and longer degradation time. MATERIAL AND METHODS: For evaluation of the tissue response the new PDS mesh was implanted as abdominal wall replacement in each five rats for 7, 21, or 90 days, respectively, and compared to a PG mesh. Histological analysis included HE staining with measurement of the size of the granuloma and immunoshistochemistry for TUNEL, Ki67, TNF-R2, MMP-2, YB1, FVIII, gas6, AXL. Parameters for neovascularization and nerve ingrowth were analyzed. RESULTS: The inflammatory and fibrotic tissue reaction is attenuated with PDS in comparison to PG, e.g., the size of the granuloma was smaller with less cell turnover, and less remodeling as represented by, e.g., reduction of apoptosis, expression of MMP-2, or TNF-R2. The number of ingrowing nerves and vessels explored via AXL, gas6, and factor VIII was increased in the PDS mesh. CONCLUSION: The results from the present investigation showed that a mesh can be constructed of monofilament PDS that induce significant less inflammatory and fibrotic reaction, however permits fluid drainage and preserves elasticity.
Assuntos
Materiais Biocompatíveis , Polidioxanona , Ácido Poliglicólico , Telas Cirúrgicas , Cicatrização/fisiologia , Animais , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Granuloma de Corpo Estranho/patologia , Masculino , Modelos Animais , Ratos , Ratos Sprague-DawleyRESUMO
Many previous studies have attempted to gain insight into the underlying pathophysiology of schizophrenia by studying postmortem brain tissues of schizophrenia patients. However, such analyses can be confounded by artifactual features of this approach such as lengthy agonal state and postmortem interval times. As several aspects of schizophrenia are also manifested at the peripheral level in proliferating cell types, we have studied the disorder through systematic transcriptomic and proteomic analyses of skin fibroblasts biopsied from living patients. We performed comparative transcriptomic and proteomic profiling to characterize skin fibroblasts from schizophrenia patients compared to healthy controls. Transcriptomic profiling using cDNA array technology showed that pathways associated with cell cycle regulation and RNA processing were altered in the schizophrenia subjects (n = 12) relative to controls (n = 12). LC-MS(E) proteomic profiling led to identification of 16 proteins that showed significant differences in expression between schizophrenia (n = 11) and control (n = 11) subjects. Analysis in silico revealed that these proteins were also associated with proliferation and cell growth pathways. To validate these findings at the protein level, fibroblast protein extracts were analyzed by Western blotting which confirmed the differential expression of three key proteins associated with these pathways. At the functional level, we confirmed the decreased proliferation phenotype by showing that cultured fibroblasts from schizophrenia subjects (n = 5) incorporated less (3)H-thymidine into their nuclei compared to those from controls (n = 6) by day 4 over an 8 day time course study. Similar abnormalities in cell cycle and growth pathways have been reported to occur in the central nervous system in schizophrenia. These studies demonstrate that fibroblasts obtained from living schizophrenia subjects show alterations in cellular proliferation and growth pathways. Future studies aimed at characterizing such pathways in fibroblasts and other proliferating cell types from schizophrenia patients could elucidate the molecular mechanisms associated with the pathophysiology of schizophrenia and provide a useful model to support drug discovery efforts.
Assuntos
Fibroblastos/metabolismo , Perfilação da Expressão Gênica/métodos , Proteômica/métodos , Esquizofrenia/genética , Esquizofrenia/patologia , Western Blotting , Ciclo Celular/genética , Processos de Crescimento Celular/fisiologia , Células Cultivadas , Cromatografia Líquida , Simulação por Computador , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Reprodutibilidade dos Testes , Esquizofrenia/metabolismoRESUMO
To investigate the occurrence of different Klebsiella spp. in aquatic environments, a total of 208 samples of natural surface waters was examined. From half (53%) of these samples, 123 Klebsiella strains were isolated, the most common species being Klebsiella pneumoniae. A comparison of these isolates to a group of 207 clinical K. pneumoniae isolates demonstrated that water isolates of K. pneumoniae, unlike those of K. oxytoca and K. planticola, are as capable as clinical isolates of expressing putative virulence factors such as serum resistance and capsular polysaccharides, pili, and siderophores.
Assuntos
Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Klebsiella/patogenicidade , Microbiologia da Água , Proteínas de Bactérias/metabolismo , Atividade Bactericida do Sangue , Humanos , Incidência , Klebsiella/classificação , Klebsiella/isolamento & purificação , VirulênciaRESUMO
BACKGROUND: Most test systems for acetylcholinesterase activity (E.C.3.1.1.7.) are using toxic inhibitors (BW284c51 and iso-OMPA) to distinguish the enzyme from butyrylcholinesterase (E.C.3.1.1.8.) which occurs simultaneously in the cerebrospinal fluid. Applying Ellman's colorimetric method, we were looking for a non-toxic inhibitor to restrain butyrylcholinesterase activity. Based on results of previous in vitro studies bupivacaine emerged to be a suitable inhibitor. RESULTS: Pharmacokinetic investigations with purified cholinesterases have shown maximum inhibition of butyrylcholinesterase activity and minimal interference with acetylcholinesterase activity at bupivacaine final concentrations between 0.1 and 0.5 mmol/l. Based on detailed analysis of pharmacokinetic data we developed three equations representing enzyme inhibition at bupivacaine concentrations of 0.1, 0.2 and 0.5 mmol/l. These equations allow us to calculate the acetylcholinesterase activity in solutions containing both cholinesterases utilizing the extinction differences measured spectrophotometrically in samples with and without bupivacaine. The accuracy of the bupivacaine-inhibition test could be confirmed by investigations on solutions of both purified cholinesterases and on samples of human cerebrospinal fluid. If butyrylcholinesterase activity has to be assessed simultaneously an independent test using butyrylthiocholine iodide as substrate (final concentration 5 mmol/l) has to be conducted. CONCLUSIONS: The bupivacaine-inhibition test is a reliable method using spectrophotometrical techniques to measure acetylcholinesterase activity in cerebrospinal fluid. It avoids the use of toxic inhibitors for differentiation of acetylcholinesterase from butyrylcholinesterase in fluids containing both enzymes. Our investigations suggest that bupivacaine concentrations of 0.1, 0.2 or 0.5 mmol/l can be applied with the same effect using 1 mmol/l acetylthiocholine iodide as substrate.
Assuntos
Acetilcolinesterase/análise , Bupivacaína/farmacologia , Líquido Cefalorraquidiano/enzimologia , Inibidores da Colinesterase/farmacologia , Butirilcolinesterase/metabolismo , Relação Dose-Resposta a Droga , Humanos , EspectrofotometriaRESUMO
BACKGROUND: The aim of the study was to evaluate whether perioperative epidural analgesia had any effect on the duration of postoperative ileus after laparoscopic sigmoid resection. METHODS: Twenty patients were randomized to surgery either with (group 1; n = 10) or without (group 2; n = 10) thoracic epidural analgesia. The major endpoint of the study was the time to the first postoperative bowel movement. Secondary endpoints were the interval until oral feeding was tolerated, incidence of postoperative vomiting, postoperative analgesic consumption use of patient-controlled analgesia (PCA) until the fourth day after operation, subjective pain perception and the incidence of epidural-related side-effects. RESULTS: Age, sex and American Society of Anesthesiologists classification were similar in the two groups. The first bowel movement was documented after a median of 54 (95 per cent confidence interval 32-127) h in group 1 and 77 (31-99) h in group 2 (P = 0.8). Oral feeding without additional parenteral therapy was tolerated after 48 (40-64) h in group 1 and after 56 (48-64) h in group 2 (P = 0.6). Postoperative vomiting occurred in two patients from each group. During epidural therapy the use of PCA was lower in group 1 (0.30 (0.19-0.96) mg morphine per kg) than in group 2 (0.56 (0.37-0. 80) mg/kg) (P < 0.05). Postoperative pain perception during rest and while coughing was similar in both groups. Three patients experienced reversible side-effects of epidural therapy (motor deficit, two patients; bladder dysfunction, one). CONCLUSION: Perioperative thoracic epidural analgesia did not have a clinically relevant effect on the duration of postoperative ileus after laparoscopic sigmoid resection.
Assuntos
Analgesia Epidural/métodos , Colo Sigmoide/cirurgia , Obstrução Intestinal/etiologia , Complicações Pós-Operatórias , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios/métodos , Estudos Prospectivos , Doenças do Colo Sigmoide/cirurgia , Fatores de TempoRESUMO
This is an in vitro study of the biophysical effects of holmium:YAG and neodymium-YAG lasers that was prompted by the poor clinical results obtained with lumbar percutaneous laser discus decompression (PLDD). In the absence of adequate cooling, ablation of tissue with the holmium:YAG laser causes thermal damage to the surrounding tissues. Utilizing the immediate colour-independent laser coupling effect, the holmium:YAG laser removes soft and hard tissue immediately. The low tissue penetrating power (max. 0.32 mm), together with the use of irrigation, avoids thermal problems, and this laser type with its high pulse energy and frequency is to be recommended for arthroscopic surgery. In contrast, the effects of the neodymium:YAG laser are highly dependent on tissue colour. Using this laser on light-coloured tissue only diffuse warming but no ablation of soft tissue was often seen. The depth of tissue penetration seen in our study was 0.58 mm, but is greatly dependent on the duration of application, and is much larger with long application times. In conclusion, we believe that the neodymium:YAG laser is more suitable for percutaneous intradiscal procedures than the holmium:YAG laser. For arthroscopic surgery, the holmium:YAG laser will be the better choice. The effect of each type of laser depends not only on its physical properties, but also on tissue properties (light or dark-coloured, thermal conductivity) and duration of application.
Assuntos
Terapia a Laser/instrumentação , Procedimentos Ortopédicos/instrumentação , Adulto , Idoso , Artroscópios , Fenômenos Biofísicos , Biofísica , Endoscópios , Desenho de Equipamento , Feminino , Humanos , Técnicas In Vitro , Disco Intervertebral/patologia , Disco Intervertebral/cirurgia , Vértebras Lombares/patologia , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-IdadeRESUMO
The Min (multiple intestinal neoplasia) mouse with a germline mutation in the adenomatous polyposis coli gene serves as an animal model for familial adenomatous polyposis coli (FAP). The number and age at onset of colorectal adenomas varies in the offspring of Min mice crossed with other strains. The murine gene for the secretory phospholipase A2 (PLA2G2A) was found to be the main candidate for these variations. To test the hypothesis of a correlation between PLA2G2A gene alterations and human tumor development, we screened 14 patients with FAP and 20 patients with sporadic colorectal cancer for germline and somatic PLA2G2A gene mutations. None of the individuals with FAP showed PLA2G2A germline alterations. However, a germline mutation was observed in one patient with an apparently sporadic colorectal tumor; the wildtype allele was somatically lost in the tumor of this patient.
Assuntos
Polipose Adenomatosa do Colo/genética , Neoplasias Colorretais/genética , Mutação em Linhagem Germinativa , Fosfolipases A/genética , Polipose Adenomatosa do Colo/enzimologia , Polipose Adenomatosa do Colo/patologia , Animais , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/patologia , Éxons , Feminino , Humanos , Masculino , Camundongos , Repetições de Microssatélites , Linhagem , Fosfolipases A2 , Polimorfismo Conformacional de Fita SimplesRESUMO
Blood normal and tumor tissue samples of 23 patients with sporadic colorectal tumors were screened for DNA alterations in the tumor relevant genes APC, K-ras, DCC and p53. Six different microsatellite regions were analyzed for instability by a new developed non-radioactive method. Somatic DNA alterations were found in 17 tumor samples: 13 carried single or multiple changes in single genes; six carried alterations in microsatellites; two tumors showed tumor suppressor gene mutations in addition to microsatellite changes. We found no indications of correlations between current genetic models of colorectal tumor progression and the established TNM system for histopathological tumor classification.