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1.
Genomics ; 115(6): 110723, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37804957

RESUMO

Allopolyploids often experience subgenome dominance, with one subgenome showing higher levels of gene expression and greater gene retention. Here, we address the functionality of both subgenomes of allotetraploid common carp (Cyprinus carpio) by analysing a functional network of interferon-stimulated genes (ISGs) crucial in anti-viral immune defence. As an indicator of subgenome dominance we investigated retainment of a core set of ohnologous ISGs. To facilitate our functional genomic analysis a high quality genome was assembled (WagV4.0). Transcriptome data from an in vitro experiment mimicking a viral infection was used to infer ISG expression. Transcriptome analysis confirmed induction of 88 ISG ohnologs on both subgenomes. In both control and infected states, average expression of ISG ohnologs was comparable between the two subgenomes. Also, the highest expressing and most inducible gene copies of an ohnolog pair could be derived from either subgenome. We found no strong evidence of subgenome dominance for common carp.


Assuntos
Carpas , Genoma de Planta , Animais , Humanos , Tetraploidia , Carpas/genética , Duplicação Gênica , Perfilação da Expressão Gênica
2.
Ned Tijdschr Geneeskd ; 162: D2155, 2018.
Artigo em Holandês | MEDLINE | ID: mdl-29424330

RESUMO

BACKGROUND: When two or more people fall ill after eating the same food, this is called an outbreak of food poisoning or food-related infection. In the Netherlands, physicians have to notify the Municipal Health Services (GGD) of such outbreaks. The GGD informs the Netherlands Food and Consumer Product Safety Authority (NVWA). CASE DESCRIPTION: Two clusters of scombroid poisoning (histamine poisoning in this case after eating tuna) occurred in one month. Due to the quick reporting of patients by physicians, the GGD and the NVWA immediately tracked down the source. In both clusters the NVWA confirmed high histamine levels in tuna. In reaction to these findings and the first cluster, the supplier recalled the tuna batch. This may have prevented other cases of food poisoning. In the second cluster, the implicated tuna batch had already been sold. CONCLUSION: Timely notification by physicians of food poisoning or food-related outbreaks to the GGD enables swift tracing of the source and appropriate measures by the GGD and the NVWA..


Assuntos
Notificação de Doenças , Surtos de Doenças/prevenção & controle , Doenças Transmitidas por Alimentos , Toxinas Marinhas/isolamento & purificação , Papel do Médico , Atum , Animais , Notificação de Doenças/legislação & jurisprudência , Notificação de Doenças/normas , Doenças Transmitidas por Alimentos/diagnóstico , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/etiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Humanos , Países Baixos/epidemiologia
3.
BMC Genomics ; 17: 701, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27590662

RESUMO

BACKGROUND: The common carp (Cyprinus carpio) is the oldest, most domesticated and one of the most cultured fish species for food consumption. Besides its economic importance, the common carp is also highly suitable for comparative physiological and disease studies in combination with the animal model zebrafish (Danio rerio). They are genetically closely related but offer complementary benefits for fundamental research, with the large body mass of common carp presenting possibilities for obtaining sufficient cell material for advanced transcriptome and proteome studies. RESULTS: Here we have used 19 different tissues from an F1 hybrid strain of the common carp to perform transcriptome analyses using RNA-Seq. For a subset of the tissues we also have performed deep proteomic studies. As a reference, we updated the European common carp genome assembly using low coverage Pacific Biosciences sequencing to permit high-quality gene annotation. These annotated gene lists were linked to zebrafish homologs, enabling direct comparisons with published datasets. Using clustering, we have identified sets of genes that are potential selective markers for various types of tissues. In addition, we provide a script for a schematic anatomical viewer for visualizing organ-specific expression data. CONCLUSIONS: The identified transcriptome and proteome data for carp tissues represent a useful resource for further translational studies of tissue-specific markers for this economically important fish species that can lead to new markers for organ development. The similarity to zebrafish expression patterns confirms the value of common carp as a resource for studying tissue-specific expression in cyprinid fish. The availability of the annotated gene set of common carp will enable further research with both applied and fundamental purposes.


Assuntos
Carpas/genética , Carpas/metabolismo , Proteoma , Transcriptoma , Animais , Biologia Computacional/métodos , Europa (Continente) , Perfilação da Expressão Gênica , Genoma , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Especificidade de Órgãos , Proteômica
4.
J Intern Med ; 279(3): 283-92, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26553486

RESUMO

BACKGROUND: Pronounced weight gain frequently complicates insulin therapy in patients with type 2 diabetes (T2DM). We have previously reported that addition of liraglutide for 26 weeks can reverse insulin-associated weight gain, decrease insulin dose and improve glycaemic control, as compared with continuation of standard insulin treatment. OBJECTIVES: To investigate whether the beneficial effects of liraglutide are sustained up to 52 weeks and whether similar effects could be obtained when liraglutide is added 6 months later. METHODS: Adult T2DM patients with ≥ 4% weight gain within 16 months of insulin therapy completing the first 26-week trial period of open-label addition of liraglutide 1.8 mg day(-1) (n = 26) versus continuation of standard insulin therapy (n = 24) were all treated with liraglutide for another 26 weeks. Results were analysed according to the intention-to-treat principle. RESULTS: Overall, 24 (92%) and 18 (75%) patients originally assigned to liraglutide and standard therapy, respectively, completed the study. Addition of liraglutide decreased body weight to a similar extend when given in the first 26 weeks (liraglutide group) or second 26 weeks (original standard therapy group): -4.4 vs. -4.3 kg (difference -0.32 kg, 95% confidence interval -2.2 to 1.6 kg; P = 0.74). Similar results were also seen in the two groups with regard to decrease in haemoglobin A1c (HbA1c ) (-0.77 vs. -0.66%; P = 0.23) and insulin dose (-28 vs. -26 U day(-1) ; P = 0.32). In both groups, 22% of patients could discontinue insulin. Continuation of liraglutide until 52 weeks led to sustained effects on body weight, HbA1c and insulin-dose requirements. CONCLUSION: In T2DM patients with pronounced insulin-associated weight gain, addition of liraglutide within 2 years leads to sustained reversal of body weight, improved glycaemic control and decrease in insulin dose. Thus, liraglutide offers a valuable therapeutic option.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina/efeitos adversos , Liraglutida/uso terapêutico , Aumento de Peso/efeitos dos fármacos , Feminino , Humanos , Insulina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
5.
Clin Microbiol Infect ; 20(6): 488-96, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24890710

RESUMO

Biological weapons achieve their intended target effects through the infectivity of disease-causing infectious agents. The ability to use biological agents in warfare is prohibited by the Biological and Toxin Weapon Convention. Bioterrorism is defined as the deliberate release of viruses, bacteria or other agents used to cause illness or death in people, but also in animals or plants. It is aimed at creating casualties, terror, societal disruption, or economic loss, inspired by ideological, religious or political beliefs. The success of bioterroristic attempts is defined by the measure of societal disruption and panic, and not necessarily by the sheer number of casualties. Thus, making only a few individuals ill by the use of crude methods may be sufficient, as long as it creates the impact that is aimed for. The assessment of bioterrorism threats and motives have been described before. Biocrime implies the use of a biological agent to kill or make ill a single individual or small group of individuals, motivated by revenge or the desire for monetary gain by extortion, rather than by political, ideological, religious or other beliefs. The likelihood of a successful bioterrorist attack is not very large, given the technical difficulties and constraints. However, even if the number of casualties is likely to be limited, the impact of a bioterrorist attack can still be high. Measures aimed at enhancing diagnostic and therapeutic capabilities and capacities alongside training and education will improve the ability of society to combat 'regular' infectious diseases outbreaks, as well as mitigating the effects of bioterrorist attacks.


Assuntos
Armas Biológicas , Guerra Biológica , Bioterrorismo , Técnicas de Laboratório Clínico/métodos , Testes Diagnósticos de Rotina/métodos , Animais , Defesa Civil , Humanos , Plantas
6.
Diabetologia ; 56(12): 2573-81, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24065152

RESUMO

AIMS/HYPOTHESIS: Insulin therapy in patients with type 2 diabetes mellitus is accompanied by weight gain characterised by an increase in abdominal fat mass. The expansion of adipose tissue mass is generally paralleled by profound morphological and inflammatory changes. We hypothesised that the insulin-associated increase in fat mass would also result in changes in the morphology of human subcutaneous adipose tissue and in increased inflammation, especially when weight gain was excessive. METHODS: We investigated the effects of weight gain on adipocyte size, macrophage influx, and mRNA expression and protein levels of key inflammatory markers within the adipose tissue in patients with type 2 diabetes mellitus before and 6 months after starting insulin therapy. RESULTS: As expected, insulin therapy significantly increased body weight. At the level of the subcutaneous adipose tissue, insulin treatment led to an influx of macrophages. When comparing patients gaining no or little weight with patients gaining >4% body weight after 6 months of insulin therapy, both subgroups displayed an increase in macrophage influx. However, individuals who had gained weight had higher protein levels of monocyte chemoattractant protein-1, TNF-α and IL-1ß after 6 months of insulin therapy compared with those who had not gained weight. CONCLUSIONS/INTERPRETATION: We conclude that insulin therapy in patients with type 2 diabetes mellitus improved glycaemic control but also induced body weight gain and an influx of macrophages into the subcutaneous adipose tissue. In patients characterised by a pronounced insulin-associated weight gain, the influx of macrophages into the adipose tissue was accompanied by a more pronounced inflammatory status. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00781495. FUNDING: The study was funded by European Foundation for the Study of Diabetes and the Dutch Diabetes Research Foundation.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inflamação/tratamento farmacológico , Insulina/uso terapêutico , Macrófagos/efeitos dos fármacos , Aumento de Peso/efeitos dos fármacos , Composição Corporal , Peso Corporal , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/imunologia , Feminino , Humanos , Inflamação/sangue , Injeções Subcutâneas , Insulina/análogos & derivados , Interleucina-1beta/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Gordura Subcutânea/imunologia , Resultado do Tratamento , Fator de Necrose Tumoral alfa , Aumento de Peso/imunologia
7.
Endocrinology ; 153(12): 5866-74, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23117929

RESUMO

Autophagy, an evolutionary conserved process aimed at recycling damaged organelles and protein aggregates in the cell, also modulates proinflammatory cytokine production in peripheral blood mononuclear cells. Because adipose tissue inflammation accompanied by elevated levels of proinflammatory cytokines is characteristic for the development of obesity, we hypothesized that modulation of autophagy alters adipose tissue inflammatory gene expression and secretion. We tested our hypothesis using ex vivo and in vivo studies of human and mouse adipose tissue. Levels of the autophagy marker LC3 were elevated in sc adipose tissue of obese vs. lean human subjects and positively correlated to both systemic insulin resistance and morphological characteristics of adipose tissue inflammation. Similarly, autophagic activity levels were increased in adipose tissue of obese and insulin resistant animals as compared with lean mice. Inhibition of autophagy by 3-methylalanine in human and mouse adipose tissue explants led to a significant increase in IL-1ß, IL-6, and IL-8 mRNA expression and protein secretion. Noticeably, the enhancement in IL-1ß, IL-6, and keratinocyte-derived chemoattractant (KC) by inhibition of autophagy was more robust in the presence of obesity. Similar results were obtained by blocking autophagy using small interfering RNA targeted to ATG7 in human Simpson-Golabi-Behmel syndrome adipocytes. Our results demonstrate that autophagy activity is up-regulated in the adipose tissue of obese individuals and inhibition of autophagy enhances proinflammatory gene expression both in adipocytes and adipose tissue explants. Autophagy may function to dampen inflammatory gene expression and thereby limit excessive inflammation in adipose tissue during obesity.


Assuntos
Tecido Adiposo/metabolismo , Autofagia , Citocinas/metabolismo , Obesidade/metabolismo , Animais , Humanos , Inflamação , Interleucina-1beta/biossíntese , Interleucina-6/biossíntese , Interleucina-8/biossíntese , Leucócitos Mononucleares/citologia , Camundongos , Proteínas Associadas aos Microtúbulos/biossíntese , Proteínas Associadas aos Microtúbulos/metabolismo , RNA Interferente Pequeno/metabolismo , Regulação para Cima
8.
Endocrine ; 39(2): 190-7, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21069577

RESUMO

To investigate the contribution of glycosylated haemoglobin change (HbA1c) on body weight in patients with type 2 diabetes after start of insulin therapy. We analysed 122 individual weight-profiles in relation to the change in HbA1c per se in these patients up to 36 months after the start of insulin therapy. Data were analysed separately for the first 9 months after commencement of insulin therapy and for the period thereafter. Within the first 9 months of insulin therapy mean body weight increased by 0.52 kg per month. HbA1c decreased from 9.9 ± 1.8 to 7.9 ± 1.3%. Only 12% of the initial weight gain could be attributed to the change in HbA1c. Furthermore, the mean monthly increase in body weight gain was reduced by 0.006 kg for every 1 kg higher body weight at baseline. From 9 to 36 months after start of insulin therapy, body weight increased by 0.1 kg/month, which was independent of change in HbA1c. Improvement of glycaemic control per se contributes little to initial weight gain after start of insulin therapy in patients with T2DM. After 9 months of insulin treatment, weight gain is unrelated to change in glycosylated haemoglobin. Other factors have to be responsible for weight gain after start of insulin therapy.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas/análise , Hiperglicemia/epidemiologia , Hipoglicemiantes/efeitos adversos , Insulina/efeitos adversos , Aumento de Peso/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Peso Corporal , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Humanos , Hiperglicemia/prevenção & controle , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Estudos Longitudinais , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Obesidade/complicações , Obesidade/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Estatística como Assunto , Fatores de Tempo
9.
Neth J Med ; 68(11): 359-66, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21116029

RESUMO

Pronounced weight gain after start of insulin therapy in patients with type 2 diabetes mellitus (T2DM) may offset beneficial effects conferred by the improvement of glycaemic control. This hypothesis was tested by comparing the cardiometabolic risk profile of a group of type 2 diabetes patients with a marked increase in body weight ('gainers) after the start of insulin treatment and a similar group without any or only minimal weight gain ('non-gainers'). In a cross-sectional study, we compared two predefined groups of patients with T2DM who had been on insulin therapy for a mean of 4.0 years: 'gainers' vs 'non-gainers'. Cardiometabolic risk was assessed by measuring fat content and distribution (physical examination, bioelectrical impedance analysis, dual energy X-ray absorption, and magnetic resonance imaging), liver fat content (magnetic resonance spectroscopy), physical activity levels (Sensewear® armband) and plasma markers. Each subgroup consisted of 14 patients. Gainers had significantly more total body and trunk fat (especially subcutaneous fat) compared with no-gainers. Gainers had similar liver fat content, and slightly higher levels of fat hormones. Furthermore, gainers performed significantly less physical activity. Lastly, gainers had higher total cholesterol, low-density lipoprotein cholesterol, and alanine aminotransferase levels with similar cholesterol-lowering treatment. Patients with T2DM who show pronounced weight gain during insulin therapy have a less favourable cardiometabolic risk profile compared with patients who show no or minimal weight gain.


Assuntos
Doenças Cardiovasculares/epidemiologia , Complicações do Diabetes , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/efeitos adversos , Insulina/efeitos adversos , Aumento de Peso/efeitos dos fármacos , Idoso , Distribuição da Gordura Corporal , Peso Corporal/efeitos dos fármacos , Doenças Cardiovasculares/patologia , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Feminino , Hemoglobinas Glicadas , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Masculino , Doenças Metabólicas/epidemiologia , Doenças Metabólicas/patologia , Metformina/efeitos adversos , Pessoa de Meia-Idade , Atividade Motora , Países Baixos/epidemiologia , Medição de Risco , Fatores de Risco , Fatores de Tempo
10.
ScientificWorldJournal ; 10: 2207-14, 2010 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-21057733

RESUMO

We review a recently discovered developmental mechanism. Anterior-posterior positional information for the vertebrate trunk is generated by sequential interactions between a timer in the early nonorganizer mesoderm (NOM) and the Spemann organizer (SO). The timer is characterized by temporally collinear activation of a series of Hox genes in the early ventral and lateral mesoderm (i.e., the NOM) of the Xenopus gastrula. This early Hox gene expression is transient, unless it is stabilized by signals from the SO. The NOM and the SO undergo timed interactions due to morphogenetic movements during gastrulation, which lead to the formation of an anterior-posterior axial pattern and stable Hox gene expression. When separated from each other, neither the NOM nor the SO is able to induce anterior-posterior pattern formation of the trunk. We present a model describing that the NOM acquires transiently stable hox codes and spatial collinearity, and that morphogenetic movements then continually bring new cells from the NOM within the range of SO signals that cause transfer of the mesodermal pattern to a stable pattern in neurectoderm and, thereby, create patterned axial structures. In doing so, the age of the NOM, but not the age of the SO, defines positional values along the anterior-posterior axis. We postulate that the temporal information from the NOM is linked to mesodermal Hox expression. The role of the SO for trunk patterning turns out to be the induction of neural tissue as prerequisite for neural hox patterning. Apparently, development of a stable anterior-posterior pattern requires neural hox patterning. We believe that this mechanism represents a developmental principle.


Assuntos
Padronização Corporal , Mesoderma/embriologia , Organizadores Embrionários/embriologia , Vertebrados/embriologia , Animais , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Mesoderma/metabolismo , Morfogênese , Placa Neural/embriologia , Placa Neural/metabolismo , Organizadores Embrionários/metabolismo , Vertebrados/genética , Xenopus/embriologia , Xenopus/genética
11.
Genomics ; 95(5): 250-5, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19944143

RESUMO

Here, we review a recently discovered developmental mechanism. Anterior-posterior positional information for the vertebrate trunk is generated by sequential interactions between a timer in the early non-organiser mesoderm and the Spemann organiser. The timer is characterised by temporally colinear activation of a series of Hox genes in the early ventral and lateral mesoderm (i.e., the non-organiser mesoderm) of the Xenopus gastrula. This early Hox gene expression is transient, unless it is stabilised by signals from the Spemann organiser. The non-organiser mesoderm (NOM) and the Spemann organiser undergo timed interactions during gastrulation which lead to the formation of an anterior-posterior axis and stable Hox gene expression. When separated from each other, neither non-organiser mesoderm nor the Spemann organiser is able to induce anterior-posterior pattern formation of the trunk. We present a model describing that NOM acquires transiently stable hox codes and spatial colinearity after involution into the gastrula and that convergence and extension then continually bring new cells from the NOM within the range of organiser signals that cause transfer of the mesodermal pattern to a stable pattern in neurectoderm and thereby create patterned axial structures. In doing so, the age of the non-organiser mesoderm, but not the age of the organiser, defines positional values along the anterior-posterior axis. We postulate that the temporal information from the non-organiser mesoderm is linked to mesodermal Hox expression. The role of the organiser was investigated further and this turns out to be only the induction of neural tissue. Apparently, development of a stable axial hox pattern requires neural hox patterning.


Assuntos
Gástrula/embriologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Proteínas de Homeodomínio/metabolismo , Transdução de Sinais/fisiologia , Proteínas de Xenopus/metabolismo , Animais , Mesoderma/embriologia , Placa Neural/embriologia , Xenopus laevis
14.
Neth J Med ; 64(6): 202-5, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16788220

RESUMO

The case of a 63-year-old woman who presented with status epilepticus, coma and hypoventilation is reported. A primary neurological cause was considered. Hypothermia led to further investigations and a diagnosis of severe hypothyroidism. The neurological complications of hyperthyriodism include alteration in mental status with slowness, decreased concentration and lethargy, headache, cranial nerve palsies, dysarthria, hoarseness, myopathy, neuropathy, reflex changes, ataxia, and psychotic episodes. Our patient suffered from a rare consequence of severe hypothyroidism presenting with status epilepticus and she died despite treatment. To our knowledge this is the second patient to be reported with myxoedema coma with this kind of presentation. Despite therapeutic options, there is a high mortality rate.


Assuntos
Atrofia/patologia , Coma/complicações , Hipotireoidismo/complicações , Hipotireoidismo/tratamento farmacológico , Mixedema/complicações , Estado Epiléptico/etiologia , Glândula Tireoide/patologia , Tiroxina/uso terapêutico , Evolução Fatal , Feminino , Escala de Coma de Glasgow , Humanos , Pessoa de Meia-Idade , Doenças Respiratórias/etiologia
17.
Exp Eye Res ; 64(6): 1037-41, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9301485

RESUMO

Clones derived from SV40-transformed hamster lens cells have at least three different stable morphologies. Biochemical differences between the three cell types that become detectable after transfection of the alpha A-crystallin gene do exist at the level of alpha B-crystallin and small heat shock protein (HSP27) expression. Furthermore one cell type is capable of alternative splicing of the hamster alpha A-crystallin gene, whereas another one cannot express alpha AIns-crystallin.


Assuntos
Linhagem Celular Transformada/metabolismo , Transformação Celular Viral , Cristalino/metabolismo , Vírus 40 dos Símios , Animais , Linhagem Celular Transformada/citologia , Cricetinae , Cristalinas/genética , Cristalinas/metabolismo , Expressão Gênica , Proteínas de Choque Térmico/metabolismo , Cristalino/citologia , Transfecção
18.
J Clin Periodontol ; 24(5): 346-53, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9178115

RESUMO

The proteolytic activities of oral bacteria are thought to play an important role in the aetiology of dental abscesses. Bacteria-derived proteases may contribute to tissue destruction, and are likely to impair host defence by degrading immunoglobulins and complement. Degraded periodontal tissue and tissue fluid are likely to constitute essential sources of nutrients in the abscess. Tissue fluid, which is derived from serum, is rich in protein and poor in carbohydrate, suggesting that breakdown of protein and fermentation of amino acids is a crucial step to generate energy for growth of the microflora. The number of oral bacterial species that perform hydrolytic cleavage of protein into polypeptides, the first step in protein degradation, is relatively small compared to the large majority of peptidase-producing species. In this study, we therefore investigated the growth-promoting effect of proteinase-producing species like Prevotella intermedia and Actinomyces meyeri on the growth of some non-proteinase producing bacteria in mixed cultures. We used serum as a substitute for the supposed natural substrate of the abscess microflora. The breakdown of serum proteins was investigated using capillary electrophoresis. Poor growth was found in mono- and mixed cultures of non-proteinase producing species Eubacterium lentum, Fusobacterium nucleatum. Peptostreptococcus micros, and Streptococcus intermedius. The presence of P. intermedia in mixed cultures strongly enhanced growth of these 4 species, according to the hypothesis that the growth of the mixed cultures was peptide-limited. The enhanced growth of P. intermedia in pronase-digested serum indicated peptide-limited growth of this organism in serum, despite its production of proteinase. We found that growth of monocultures of Actinomyces meyeri was poor. In contrast, A. meyeri grew well in mixed cultures and its presence stimulated growth of F. nucleatum and P. micros, suggesting a synergistic relationship. The growth of mono- and mixed cultures was investigated using one representative strain of each species. Thus, there is a small risk of having selected unique strains. Proteinase inhibitors reduced the growth of Porphyromonas gingivalis, Prevotella nigrescens, and P. intermedia in trypticase peptone-yeast extract medium with, and without, IgG. Our study indicated that proteinase-producing organisms play a key role in mixed cultures of oral bacteria in human serum by providing polypeptides for growth. This may explain their association with dental abscesses.


Assuntos
Actinomyces/enzimologia , Bactérias Anaeróbias/crescimento & desenvolvimento , Prevotella intermedia/enzimologia , Bactérias Anaeróbias/metabolismo , Sangue/microbiologia , Eletroforese das Proteínas Sanguíneas , Proteínas Sanguíneas/metabolismo , Técnicas de Cocultura , Contagem de Colônia Microbiana , Ecossistema , Endopeptidases/metabolismo , Humanos , Abscesso Periodontal/microbiologia , Inibidores de Proteases/metabolismo
19.
J Clin Periodontol ; 23(8): 717-23, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8877656

RESUMO

Oral bacteria play an important rôle in the causation of oro-facial abscesses. However, they can also be involved in brain, liver and lung abscesses. To persist, it is essential that these bacteria can grow on those sites. The main source of nutrients for growth in abscesses is likely to be tissue exudate, which is rich in serum-derived proteins, and relatively poor in free amino acids and carbohydrates. Degradation of intact proteins seems a crucial step in providing the peptides necessary for energy generation. The aim of this study was to investigate the capacity of microorganisms from asscesses to degrade serum proteins, in particular immunoglobulins. To this end, samples were taken by aspiration from 16 odontogenic abscesses. It was found that pus from abscesses differed strongly in the concentration of viable bacterial cells. The ability of the abscess microflora to degrade serum proteins was investigated after growth of the sample in heat-inactivated human serum. The microflora from abscesses with a high concentration (n = 10) of bacteria strongly degraded immunoglobulins, whereas breakdown of immunoglobulins was virtually absent after growth of the microflora from low-bacterial concentration (n = 6) abscesses. Bacteriological analyses revealed the presence of at least one proteinase-producing species, like Porphyromonas, black-pigmented Prevotella species, or Actinomyces meyeri, in abscesses with a high density of bacteria, but not in those with low bacterial density. The results indicate that the capacity to degrade intact proteins, in particular immunoglobulins, is a major determinant of bacterial growth in abscesses.


Assuntos
Imunoglobulinas/metabolismo , Abscesso Periapical/metabolismo , Abscesso Periapical/microbiologia , Adulto , Bactérias Anaeróbias/isolamento & purificação , Bactérias Anaeróbias/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Abscesso Periapical/imunologia
20.
Nucleic Acids Res ; 23(15): 2815-22, 1995 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-7659502

RESUMO

The human platelet-derived growth factor (PDGF) B chain precursor is usually translated from a 3.5 kb c-sis/PDGF B gene transcript. The first exon of the c-sis/gene contains the code for the signal peptide of the PDGF B chain precursor, preceded by a 1 kb long untranslated sequence with potent translation inhibitory activity. In this paper we show that a novel 2.6 kb c-sis mRNA present in the human choriocarcinoma cell line JEG-3 initiates at an alternative exon 1, which we refer to as exon 1a. The 90 bp long exon 1a is located in the center of the first intron of the gene. It coincides with a very pronounced DNase-I-hypersensitive site and is preceded by a functional promoter. Of the three ATG codons present in exon 1a, the third one perfectly matches the criteria of a consensus start codon. It initiates an open reading frame that is continuous with the code for the PDGF B chain precursor but lacks the code for a signal peptide. We conclude that this novel 2.6 kb c-sis mRNA species lacks the strong translation inhibitory potential of the regular exon 1 and contains the code for a PDGF B-like protein that may be targeted to the cell nucleus.


Assuntos
Processamento Alternativo/genética , Íntrons/genética , Fator de Crescimento Derivado de Plaquetas/genética , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/genética , Sequência de Aminoácidos , Sequência de Bases , Coriocarcinoma , Códon de Iniciação/genética , DNA de Neoplasias/genética , Desoxirribonuclease I/metabolismo , Éxons/genética , Humanos , Dados de Sequência Molecular , Fases de Leitura Aberta/genética , Proteínas Proto-Oncogênicas c-sis , RNA Neoplásico/biossíntese , Transcrição Gênica/genética , Células Tumorais Cultivadas
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