RESUMO
PURPOSE: Cross-sectional imaging by computed tomography (CT) is associated with higher radiation dose compared to plain X-ray. The Uro Dyna-CT provides CT-like images in the endourological operating room. Our aim was to reduce the radiation exposure of endourological patients with the Uro Dyna-CT and optimize the cross-sectional image quality. MATERIALS AND METHODS: For the hard contrast protocol, two artificial stones were placed in a Rando-Alderson phantom's left kidney region. Relevant parameters of the standard abdomen protocol were changed. After each modification, two urologists subjectively evaluated the image quality. We developed two customized protocols (standard, low-dose) for hard contrast imaging. To optimize the examination protocol for soft tissue imaging a standardized cone beam phantom was used. Parameters of the preset high-resolution protocol were changed to develop a protocol with similar objective image quality but lower radiation dose. To evaluate the effective radiation dose we embedded 129 thermoluminescence dosimeters in the kidney and ureter region of the Rando-Alderson phantom and performed each protocol five times (stone, soft tissue) and ten times (low-dose protocol). Mean effective dose values per 3D-examination were calculated. RESULTS: We detected a dose area product (DAP) 776.2 (standard) and 163.5 µGym(2) (low-dose) for the stone protocols with an effective dose of 1.96 and 0.33 mSv, respectively. The soft tissue protocol produced a DAP of 5,070 µGym(2) and an effective dose of 7.76 mSv. CONCLUSION: Our newly developed examination protocols for the Uro Dyna-CT provide CT-like image quality during urological interventions with low radiation dose.
Assuntos
Protocolos Clínicos , Cálculos Renais/diagnóstico por imagem , Imagens de Fantasmas , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Técnicas de Diagnóstico Urológico/normasRESUMO
PURPOSE: The influence of short-term severe thyroid hormone deficiency on sleep is currently still unknown. Several studies have demonstrated an effect of long-term hypothyroidism on sleep disorders due to anatomical changes of the pharynx or body mass. The aim of this preliminary study, however, is to evaluate the changes in sleep patterns of patients with short-term hypothyroidism to elucidate the isolated effect of thyroid hormone withdrawal before anatomical changes can potentially occur. METHODS: Ten patients with differentiated thyroid carcinoma were enrolled in this study. Two patients discontinued the study and one patient was finally excluded due to obesity, so that the datasets of seven patients were available for study analysis. During the course of carcinoma treatment, each patient had previously undergone total thyroidectomy and I-131 remnant ablation. Polysomnographic measurements were performed twice: (1) over the course of two consecutive nights during severe thyroid hormone deficiency after levothyroxine withdrawal and prior to further diagnostics and therapy and (2) during euthyroidism after substitution with levothyroxine. RESULTS: Comparison of the Epworth Sleepiness Scale during hypo- and euthyroidism for each patient revealed no statistically significant difference. Furthermore, the comparison of polysomnographic parameters like (1) apnea-hypopnea index, (2) the duration of various sleep stages, (3) duration of rapid eye movement sleep, (4) latency until rapid eye movement sleep, (5) total sleep time, (6) periodic leg movements, and (7) arousal index showed no statistically significant differences between the hypothyroid or euthyroid state. CONCLUSIONS: We conclude that, in this preliminary experimental setting, short-term severe thyroid hormone deficiency per se does not cause sleep disturbances and a feeling of fatigue as described in other studies may be due to changes in perception or brain metabolism during hypothyroidism.
Assuntos
Hipotireoidismo/fisiopatologia , Radioisótopos do Iodo/uso terapêutico , Polissonografia , Complicações Pós-Operatórias/fisiopatologia , Apneia Obstrutiva do Sono/fisiopatologia , Fases do Sono/fisiologia , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Adulto , Idoso , Nível de Alerta/fisiologia , Distúrbios do Sono por Sonolência Excessiva/tratamento farmacológico , Distúrbios do Sono por Sonolência Excessiva/fisiopatologia , Feminino , Humanos , Hipotireoidismo/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/tratamento farmacológico , Apneia Obstrutiva do Sono/tratamento farmacológico , Inquéritos e Questionários , Tiroxina/uso terapêuticoRESUMO
Radical hysterectomy with pelvic lymphadenectomy is the standard surgical treatment for patients with early stage cervical cancer. The majority of radical hysterectomies are performed with the open technique. However, laparoscopic, combined laparoscopic and vaginal, and robotic-assisted approaches may also be used. Compared with the abdominal radical hysterectomy (ARH), laparoscopic techniques are associated with less blood loss, shorter hospital stay, better cosmesis, and faster recovery. A further breakthrough in laparoscopic technique can only be made if safety and oncological clearance are comparable with ARH. We describe the technique and results of laparoscopic assisted radical vaginal hysterectomy and the transition to vaginal assisted laparoscopic radical hysterectomy.
Assuntos
Histerectomia Vaginal/métodos , Laparoscopia/métodos , Neoplasias do Colo do Útero/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Perda Sanguínea Cirúrgica/prevenção & controle , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Humanos , Complicações Intraoperatórias/etiologia , Curva de Aprendizado , Tempo de Internação , Metástase Linfática , Pessoa de Meia-Idade , Radioterapia Adjuvante , Fatores de Tempo , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/radioterapia , Adulto JovemRESUMO
In this contribution, we analyse scenarios of advanced wastewater treatment for the removal of micropollutants. By this we refer to current mainstream, broad spectrum processes including ozonation and sorption onto activated carbon. We argue that advanced treatment requires properly implemented tertiary (nutrient removal) treatment in order to be effective. We review the critical aspects of the main advanced treatment options, their advantages and disadvantages. We propose a quantification of the costs of implementing advanced treatment, as well as upgrading plants from secondary to tertiary treatment when needed, and we illustrate what drives the costs of advanced treatment for a set of standard configurations. We propose a cost function to represent the total costs (investment, operation and maintenance) of advanced treatment. We quantify the implications of advanced treatment in terms of greenhouse gas emissions. Based on the indicators of total toxic discharge, toxicity at the discharge points and toxicity across the stream network discussed in Pistocchi et al. (2022), we compare costs and effectiveness of different scenarios of advanced treatment. In principle the total toxic load and toxicity at the points of discharge could be reduced by about 75 % if advanced treatment processes were implemented virtually at all wastewater treatment plants, but this would entail costs of about 4 billion euro/year for the European Union as a whole. We consider a "compromise" scenario where advanced treatment is required at plants of 100 thousand population equivalents (PE) or larger, or at plants between 10 and 100 thousand PE if the dilution ratio at the discharge point is 10 or less. Under this scenario, the length of the stream network exposed to high toxicity would not increase significantly compared to the previous scenario, and the other indicators would not deteriorate significantly, while the costs would remain at about 1.5 billion Euro/year. Arguably, costs could be further reduced, without a worsening of water quality, if we replace a local risk assessment to generic criteria of plant capacity and dilution in order to determine if a WWTP requires advanced treatment.
Assuntos
Gases de Efeito Estufa , Ozônio , Poluentes Químicos da Água , Purificação da Água , Carvão Vegetal , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água/análiseRESUMO
AIMS: To characterize bio-psycho-social factors, particularly mental disorders and self-harm behaviour, associated with the development of diabetic foot ulcers. METHODS: Two groups of diabetic patients with and without foot ulcers (n=47 in each group) with similar sex, age and diabetes duration were assessed for mental disorders using the Composite International Diagnostic Interview. Self-harm behaviour, quality of life, depressive symptoms and self-compassion were rated using different standard questionnaires. RESULTS: Patients from the ulcer group visited their practitioners and/or psychotherapists less frequently in the last 12 months than patients in the control group 0 vs. 13%; P=0.026). The ulcer group patients had a history of increased alcohol consumption (43 vs. 19%; P=0.025), lower levels of education (8 vs. 10 grades; P=0.014) and income (1190 vs. 1535 /month; P=0.039). Additionally, they were less likely to be diagnosed with anxiety disorders (11 vs. 32%; P=0.022). No significant differences in glycated haemoglobin, body mass index, smoking and direct self-harm behaviour were identified. CONCLUSIONS: Patients with foot ulcers tend to exhibit lower health-conscious behaviour, particularly higher lifetime alcohol consumption, lower utilization of medical services and less general anxiety. Practitioners should be aware of these behaviours, since early detection of diabetes patients at psycho-social risk and consecutive psychological intervention may be an effective preventive strategy in avoiding the development of foot ulcers.
Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Diabetes Mellitus Tipo 2/complicações , Pé Diabético/etiologia , Neuropatias Diabéticas/psicologia , Comportamentos Relacionados com a Saúde , Cooperação do Paciente/psicologia , Autocuidado/psicologia , Adulto , Idoso , Consumo de Bebidas Alcoólicas/psicologia , Amputação Cirúrgica/psicologia , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/psicologia , Pé Diabético/fisiopatologia , Pé Diabético/psicologia , Neuropatias Diabéticas/complicações , Neuropatias Diabéticas/fisiopatologia , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente/estatística & dados numéricos , Fatores de Risco , Inquéritos e QuestionáriosRESUMO
Cytotoxicity and genotoxicity of nitrogen dioxide (NO(2)) as part of urban exhaust pollution are widely discussed as potential hazards to human health. This study focuses on toxic effects of NO(2) in realistic environmental concentrations with respect to the current limit values in a human target tissue of volatile xenobiotics, the epithelium of the upper aerodigestive tract. Nasal epithelial cells of 10 patients were cultured as an air-liquid interface and exposed to 0.01 ppm NO(2), 0.1 ppm NO(2), 1 ppm NO(2), 10 ppm NO(2) and synthetic air for half an hour. After exposure, genotoxicity was evaluated by the alkaline single-cell microgel electrophoresis (Comet) assay and by induction of micronuclei in the micronucleus test. Depression of proliferation and cytotoxic effects were determined using the micronucleus assay and trypan blue exclusion assay, respectively. The experiments revealed genotoxic effects by DNA fragmentation starting at 0.01 ppm NO(2) in the Comet assay, but no micronucleus inductions, no changes in proliferation, no signs of necrosis or apoptosis in the micronucleus assay, nor did the trypan blue exclusion assay show any changes in viability. The present data reveal a possible genotoxicity of NO(2) in urban concentrations in a screening test. However, permanent DNA damage as indicated by the induction of micronuclei was not observed. Further research should elucidate the effects of prolonged exposure.
Assuntos
Exposição Ambiental/efeitos adversos , Mucosa Nasal/efeitos dos fármacos , Dióxido de Nitrogênio/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/ultraestrutura , Humanos , Testes de MutagenicidadeRESUMO
AIMS: The purpose of this sub-study of the Outcome Reduction with Initial Glargine Intervention (ORIGIN) trial was to determine efficacy and safety of targeting normal fasting plasma glucose (FPG) levels in patients with early Type 2 diabetes treated with insulin glargine in comparison with standard care. METHODS: Participants were randomly allocated to insulin or standard care. Insulin was titrated to reach FPG Assuntos
Glicemia/metabolismo
, Diabetes Mellitus Tipo 2/tratamento farmacológico
, Diabetes Mellitus Tipo 2/metabolismo
, Hipoglicemiantes/uso terapêutico
, Insulina/análogos & derivados
, Adulto
, Idoso
, Área Sob a Curva
, Jejum
, Teste de Tolerância a Glucose
, Hemoglobinas Glicadas/análise
, Humanos
, Hipoglicemia/induzido quimicamente
, Hipoglicemiantes/administração & dosagem
, Insulina/administração & dosagem
, Insulina/uso terapêutico
, Insulina Glargina
, Insulina de Ação Prolongada
, Masculino
, Pessoa de Meia-Idade
, Período Pós-Prandial
RESUMO
In order to reach the inner membrane of the mitochondrion, multispanning carrier proteins must cross the aqueous intermembrane space. Two essential proteins of that space, Tim10p and Tim12p, were shown to mediate import of multispanning carriers into the inner membrane. Both proteins formed a complex with the inner membrane protein Tim22p. Tim10p readily dissociated from the complex and was required to transport carrier precursors across the outer membrane; Tim12p was firmly bound to Tim22p and mediated the insertion of carriers into the inner membrane. Neither protein was required for protein import into the other mitochondrial compartments. Both proteins may function as intermembrane space chaperones for the highly insoluble carrier proteins.
Assuntos
Proteínas de Transporte/metabolismo , Proteínas Fúngicas/metabolismo , Membranas Intracelulares/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras , Mitocôndrias/metabolismo , Proteínas de Saccharomyces cerevisiae , Transporte Biológico , Clonagem Molecular , Proteínas Fúngicas/genética , Genes Fúngicos , Temperatura Alta , Potenciais da Membrana , Proteínas de Membrana/genética , Translocases Mitocondriais de ADP e ATP/metabolismo , Proteínas de Transporte da Membrana Mitocondrial , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Modelos Biológicos , Chaperonas Moleculares/metabolismo , Mutagênese , Proteínas de Ligação a Fosfato , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , SolubilidadeRESUMO
So far little is known about how the antidiabetic drugs acting at the level of gastrointestinal mucosa may affect immune and cellular response to food intake. The following study investigated the association between acarbose treatment and postprandial metabolism, immune- and inflammatory activity in patients with early type 2 diabetes: The Acarbose action on low grade Inflammation and Immune response in type 2 Diabetes on Atherosclerosis risk (AIIDA) study. Middle-aged patients (n=87) with early type 2 diabetes (2 h-plasma-glucose >or=11.1 mmol/l and/or HbA1c >or=6.5%) and sub-clinical inflammation (leucocytes >or=6.2 GPt/l and/or hsCRP >or=1.0 mg/l) underwent a mixed meal load (527 kcal). Metabolic parameters and markers of subclinical inflammation were measured at fasting (0'), 2 h-postprandial (2-hpp) and 4-hpp before and after 20 weeks of treatment with acarbose or placebo. Leukocytes and lymphocytes excursion after 20 weeks of treatment was significantly reduced with acarbose 4 h after testmeal [GPt/l] (7.5 vs. 7; p<0.05; and 2.29 vs. 2.14; p<0.05, respectively). Acarbose had only marginal effects on pp glucose, FFA, triglycerides, and insulin excursion. Biomarkers of inflammation (hsCRP, MBL, and PAI1) were not affected by acarbose. Multivariate analysis reveals only baseline leukocytes and of acarbose as independent determinant of 4-h leucocytes excursion. Postprandial metabolic and inflammatory parameters were strongly interrelated. These results suggest pleiotropic effects of acarbose, which may contribute to its vasoprotective potentials.
Assuntos
Acarbose/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/imunologia , Hipoglicemiantes/uso terapêutico , Leucócitos Mononucleares/efeitos dos fármacos , Adulto , Idoso , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/sangue , Feminino , Humanos , Insulina/sangue , Contagem de Leucócitos , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Efeito Placebo , Resultado do Tratamento , Triglicerídeos/sangueRESUMO
Endothelial dysfunction (ED) has been suggested as a possible causal link between postprandial hyperglycemia and cardiovascular events in patients with type 2 diabetes. Recent trials demonstrated a reduction of cardiovascular events by treatment with alpha-glucosidase inhibitor acarbose - a drug which mainly reduces postprandial glucose excursions. We were interested to know whether patients with newly diagnosed type 2 diabetes showed postprandial ED and if so whether acarbose was able to improve this condition. Forearm blood flow (FBF) measurements for assessment of ED were performed in the fasting and postprandial state in 20 newly diagnosed type 2 diabetic patients and 10 healthy control subjects. After baseline examination, patients were randomly assigned to a 20-week treatment of acarbose 100 mg t.i.d or matching placebo, thereafter FBF measurements were repeated. FBF of patients in the fasting state was significantly impaired compared to healthy control subjects (max. FBF 5.3+/-0.7 vs. 8.0+/-0.9 ml/100 ml, p<0.02) and did not change in the postprandial state (max. FBF 5.6+/-0.7 ml/100 ml). In contrast, healthy controls showed a significant improvement of FBF in the postprandial state (11.5+/-1.2 ml/100 ml), which is compatible with postprandial ED in the group of patients. Twenty weeks of acarbose treatment did not affect either fasting or postprandial FBF in patients. Early type 2 diabetes is a state of both fasting and postprandial ED, which is not sensitive to acarbose treatment. Protective cardiovascular effects of acarbose might involve other mechanisms.
Assuntos
Acarbose/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/fisiopatologia , Endotélio Vascular/efeitos dos fármacos , Inibidores Enzimáticos/uso terapêutico , Inibidores de Glicosídeo Hidrolases , Acarbose/farmacologia , Adulto , Idoso , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/diagnóstico , Método Duplo-Cego , Endotélio Vascular/fisiopatologia , Inibidores Enzimáticos/farmacologia , Jejum , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial , Fluxo Sanguíneo RegionalRESUMO
A newly discovered family of small proteins in the yeast mitochondrial intermembrane space mediates import of hydrophobic proteins from the cytoplasm into the inner membrane. Loss of one of these chaperone-like proteins from human mitochondria results in a disease that causes deafness, muscle weakness and blindness.
Assuntos
Membranas Intracelulares/metabolismo , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Chaperonas Moleculares/metabolismo , Sequência de Aminoácidos , Animais , Transporte Biológico , Humanos , Mitocôndrias/patologia , Chaperonas Moleculares/química , Chaperonas Moleculares/genética , Dados de Sequência Molecular , SíndromeRESUMO
A simple balancing method using passive samplers over a week's period has been developed and tested successfully to determine elimination rates of 22 common micropollutants of household and industrial sources in 18 full-scale wastewater treatment plants of different design and performance. Independent reactor tests to delineate elimination rates with native sludge of the treatment plants correlated very well with the full-scale elimination rate determinations. As opposed to common assumptions, this large dataset indicated that shorter sludge retention times - read: higher active biomass - showed higher micropollutant elimination rates in many cases. Multivariate statistical analysis of the elimination rates over the 18 treatment plants was able to group compounds according to common degradation pathways and showed that sensitivity to SRT drove the grouping. The dataset also allowed to determine population equivalent normalized loads of the investigated micropollutants. The application of WWTP balancing with passive sampling makes it relatively easy to gather elimination rates and inlet loads on a much broader basis than before and gives orientation for more in-depth analysis of degradation pathways.
Assuntos
Águas Residuárias , Poluentes Químicos da Água , Esgotos , Eliminação de Resíduos LíquidosRESUMO
The TIM22 protein import pathway of the yeast mitochondrion contains several components, including a family of five proteins (Tim8p, -9p, -10p, -12p, and -13p [Tim, for translocase of inner membrane]) that are located in the intermembrane space and are 25% identical. Tim9p and Tim10p have dual roles in mediating the import of inner membrane proteins. Like the Tim8p-Tim13p complex, the Tim9p-Tim10p complex functions as a putative chaperone to guide hydrophobic precursors across the intermembrane space. Like membrane-associated Tim12p, they are members of the Tim18p-Tim22p-Tim54p membrane complex that mediates precursor insertion into the membrane. To understand the role of this family in protein import, we have used a genetic approach to manipulate the complement of the small Tim proteins. A strain has been constructed that lacks the 70-kDa soluble Tim8p-Tim13p and Tim9p-Tim10p complexes in the intermembrane space. Instead, a functional version of Tim9p (Tim9(S67C)p), identified as a second-site suppressor of a conditional tim10 mutant, maintains viability. Characterization of this strain revealed that Tim9(S67C)p and Tim10p were tightly associated with the inner membrane, the soluble 70-kDa Tim8p-Tim13p and Tim9p-Tim10p complexes were not detectable, and the rate of protein import into isolated mitochondria proceeded at a slower rate. An arrested translocation intermediate bound to Tim9(S67C)p was located in the intermembrane space, associated with the inner membrane. We suggest that the 70-kDa complexes facilitate import, similar to the outer membrane receptors of the TOM (hetero-oligomeric translocase of the outer membrane) complex, and the essential role of Tim9p and Tim10p may be to mediate protein insertion in the inner membrane with the TIM22 complex.
Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Transporte Biológico , Proteínas Fúngicas/metabolismo , Mitocôndrias/metabolismo , Proteínas de Transporte da Membrana Mitocondrial , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Ligação Proteica , Saccharomyces cerevisiae/ultraestrutura , Transdução de SinaisRESUMO
The Saccharomyces cerevisiae genes ELM1, ELM2, and ELM3 were identified on the basis of the phenotype of constitutive cell elongation. Mutations in any of these genes cause a dimorphic transition to a pseudohyphal growth state characterized by formation of expanded, branched chains of elongated cells. Furthermore, elm1, elm2, and elm3 mutations cause cells to grow invasively under the surface of agar medium. S. cerevisiae is known to be a dimorphic organism that grows either as a unicellular yeast or as filamentous cells termed pseudohyphae; although the yeast-like form usually prevails, pseudohyphal growth may occur during conditions of nitrogen starvation. The morphologic and physiological properties caused by elm1, elm2, and elm3 mutations closely mimic pseudohyphal growth occurring in conditions of nitrogen starvation. Therefore, we propose that absence of ELM1, ELM2, or ELM3 function causes constitutive execution of the pseudohyphal differentiation pathway that occurs normally in conditions of nitrogen starvation. Supporting this hypothesis, heterozygosity at the ELM2 or ELM3 locus significantly stimulated the ability to form pseudohyphae in response to nitrogen starvation. ELM1 was isolated and shown to code for a novel protein kinase homolog. Gene dosage experiments also showed that pseudohyphal differentiation in response to nitrogen starvation is dependent on the product of CDC55, a putative B regulatory subunit of protein phosphatase 2A, and a synthetic phenotype was observed in elm1 cdc55 double mutants. Thus, protein phosphorylation is likely to regulate differentiation into the pseudohyphal state.
Assuntos
Genes Fúngicos , Fosfoproteínas Fosfatases/metabolismo , Proteínas Quinases/metabolismo , Saccharomyces cerevisiae/citologia , Sequência de Aminoácidos , Diferenciação Celular , Clonagem Molecular , DNA Fúngico/genética , Dados de Sequência Molecular , Mutagênese Insercional , Nitrogênio/metabolismo , Fosfoproteínas Fosfatases/genética , Proteínas Quinases/genética , Proteína Fosfatase 2 , Mapeamento por Restrição , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/crescimento & desenvolvimento , Alinhamento de SequênciaRESUMO
Import of carrier proteins from the cytoplasm into the mitochondrial inner membrane of yeast is mediated by a distinct system consisting of two soluble 70-kDa protein complexes in the intermembrane space and a 300-kDa complex in the inner membrane, the TIM22 complex. The TIM22 complex contains the peripheral subunits Tim9p, Tim10p, and Tim12p and the integral membrane subunits Tim22p and Tim54p. We identify here an additional subunit, an 18-kDa integral membrane protein termed Tim18p. This protein is made as a 21.9-kDa precursor which is imported into mitochondria and processed to its mature form. When mitochondria are gently solubilized, Tim18p comigrates with the other subunits of the TIM22 complex on nondenaturing gels and is coimmunoprecipitated with Tim54p and Tim12p. Tim18p does not cofractionate with the TIM23 complex upon immunoprecipitation or nondenaturing gel electrophoresis. Deletion of Tim18p decreases the growth rate of yeast cells by a factor of two and is synthetically lethal with temperature-sensitive mutations in Tim9p or Tim10p. It also impairs the import of several precursor proteins into isolated mitochondria, and lowers the apparent mass of the TIM22 complex. We suggest that Tim18p functions in the assembly and stabilization of the TIM22 complex but does not directly participate in protein insertion into the inner membrane.
Assuntos
Antiporters , Proteínas de Transporte/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Transporte Biológico Ativo , Proteínas de Transporte/química , Proteínas de Transporte/genética , DNA Fúngico/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Deleção de Genes , Genes Fúngicos , Membranas Intracelulares/metabolismo , Substâncias Macromoleculares , Proteínas de Membrana/química , Proteínas de Membrana/genética , Mitocôndrias/metabolismo , Proteínas de Transporte da Membrana Mitocondrial , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Dados de Sequência Molecular , Estrutura Quaternária de Proteína , Saccharomyces cerevisiae/genéticaRESUMO
A number of microaerophilic eukaryotes lack mitochondria but possess another organelle involved in energy metabolism, the hydrogenosome. Limited phylogenetic analyses of nuclear genes support a common origin for these two organelles. We have identified a protein of the mitochondrial carrier family in the hydrogenosome of Trichomonas vaginalis and have shown that this protein, Hmp31, is phylogenetically related to the mitochondrial ADP-ATP carrier (AAC). We demonstrate that the hydrogenosomal AAC can be targeted to the inner membrane of mitochondria isolated from Saccharomyces cerevisiae through the Tim9-Tim10 import pathway used for the assembly of mitochondrial carrier proteins. Conversely, yeast mitochondrial AAC can be targeted into the membranes of hydrogenosomes. The hydrogenosomal AAC contains a cleavable, N-terminal presequence; however, this sequence is not necessary for targeting the protein to the organelle. These data indicate that the membrane-targeting signal(s) for hydrogenosomal AAC is internal, similar to that found for mitochondrial carrier proteins. Our findings indicate that the membrane carriers and membrane protein-targeting machinery of hydrogenosomes and mitochondria have a common evolutionary origin. Together, they provide strong evidence that a single endosymbiont evolved into a progenitor organelle in early eukaryotic cells that ultimately give rise to these two distinct organelles and support the hydrogen hypothesis for the origin of the eukaryotic cell.
Assuntos
Proteínas de Transporte/genética , Mitocôndrias/metabolismo , Proteínas de Protozoários/genética , Proteínas de Saccharomyces cerevisiae , Trichomonas vaginalis/química , Sequência de Aminoácidos , Animais , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Clonagem Molecular , Metabolismo Energético , Evolução Molecular , Proteínas Fúngicas/química , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Translocases Mitocondriais de ADP e ATP/química , Translocases Mitocondriais de ADP e ATP/genética , Translocases Mitocondriais de ADP e ATP/metabolismo , Dados de Sequência Molecular , Filogenia , Sinais Direcionadores de Proteínas/química , Sinais Direcionadores de Proteínas/metabolismo , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , Alinhamento de Sequência , Trichomonas vaginalis/citologiaRESUMO
OBJECTIVE: Lower-extremity amputation (LEA) is a common complication among patients with diabetes. This study tests the effects of a structured disease management program for the diabetic foot (DF) aiming to reduce the number of LEA. DESIGN, METHODS: In a prospective study design we investigate patients with DF in a system of outpatient treatment, acute in-patient care and rehabilitative treatment. Subjects were recruited since January 1(st), 2000, with the latest admission being December 31, 2004. All study participants undergo a five-year follow-up observation period. The University of Texas Wound Classification System (UT) of foot ulcers serves as basis of the documentation and analysis. We evaluated numbers of LEA, rates of ulcer healing and underlying forms of peripheral vascular disease. RESULTS: We report the results of the first patient group completing the two-year follow-up examination. In 2000, 102 subjects with new foot ulcers were consecutively included into the study. 68.6% were men, the mean age of the study population was 68.1 +/- 11.4 years and the mean diabetes duration was 19.4 +/- 10.3 years. After two years, 68 patients can still be examined. Altogether, 22 patients (21.6%) died, and 12 (11.8%) dropped out for various reasons. At the point of discharge from the clinics 35.3% of the ulcers had healed and another 44.1% were in UT grade 1. After two years, a complete healing could still be determined with 51 patients (50.0% of the cohort of the original 102 patients, or 75.0% of the subjects reaching the two-year follow-up). 10 subjects (9.8% or 14.5%) were in the UT grade 1. Eight diabetics underwent major amputation (MA) during the two-year examination period (amputation rate 7.8%). CONCLUSIONS: The primary objective of the study, a significant reduction of MA with DF patients, has been achieved. The ulcer healing rates are comparable to the reports of leading centers.
Assuntos
Pé Diabético/terapia , Idoso , Amputação Cirúrgica/estatística & dados numéricos , Pé Diabético/mortalidade , Pé Diabético/cirurgia , Humanos , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Estudos Prospectivos , Análise de SobrevidaRESUMO
The surgical therapy of oropharyngeal carcinoma by means of a free jejunum graft is an established procedure. The application of a monitor segment for postoperative flow control turned out to be a reasonable modification. In this study, we examine the results over a period of 16 years retrospectively. Between 1988 and 2004, 53 patients underwent oropharyngeal reconstructions by means of 58 free jejunum grafts at the clinic for reconstructive surgery in cooperation with the clinic for otorhinolaryngology. All patients were examined postoperatively with the help of a small jejunum loop in the function of a monitor segment to survey flap vitality. Between the 7th and 11th postoperative day the patients were administered Gastrografin to evaluate oesophagojejunal anastomoses. The survival ratio of the transplants in this series amounted to 90.6 %. All anastomoses were initially passable and leak-proof. After a complete loss of the first graft, five patients were successfully reconstructed with a second jejunum graft. In one patient, the vessel anastomoses had to be revised. In two patients, newly formed stenoses were postoperatively treated with a bougie during hospitalisation. In four patients, fistula formation was detected in the follow-up examination. Substantial advantages of the free jejunum graft compared to other alternative free or local tissue transfers are the excellent functional results, the simple local tumour monitoring and the low complication rate.
Assuntos
Carcinoma de Células Escamosas/cirurgia , Fístula Esofágica/cirurgia , Estenose Esofágica/cirurgia , Fístula/cirurgia , Jejuno/transplante , Doenças da Laringe/cirurgia , Microcirurgia/métodos , Neoplasias Orofaríngeas/cirurgia , Retalhos Cirúrgicos/irrigação sanguínea , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica/métodos , Queimaduras Químicas/patologia , Queimaduras Químicas/cirurgia , Carcinoma de Células Escamosas/patologia , Fístula Esofágica/patologia , Estenose Esofágica/patologia , Esôfago/lesões , Esôfago/cirurgia , Feminino , Fístula/patologia , Seguimentos , Humanos , Jejuno/patologia , Doenças da Laringe/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Orofaríngeas/patologia , Cuidados Pós-Operatórios , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Coleta de Tecidos e ÓrgãosRESUMO
Mitochondrial membrane permeabilization is a rate-limiting step of cell death. This process is, at least in part, mediated by opening of the permeability transition pore complex (PTPC) Several soluble proteins from the mitochondrial intermembrane space and matrix are involved in the activation of catabolic hydrolases including caspases and nucleases. We therefore investigated the composition of a mixture of proteins released from purified mitochondria upon PTPC opening. This mixture was subjected to a novel proteomics/mass spectrometric approach designed to identify a maximum of peptides. Peptides from a total of 79 known proteins or genes were identified. In addition, 21 matches with expressed sequence tags (EST) were obtained. Among the known proteins, several may have indirect or direct pro-apoptotic properties. Thus endozepine, a ligand of the peripheral benzodiazepin receptor (whose occupation may facilitate mitochondrial membrane permeabilization), was found among the released proteins. Several proteins involved in protein import were also released, namely the so-called X-linked deafness dystonia protein (DDP) and the glucose regulated protein 75 (grb75), meaning that protein import may become irreversibly disrupted in mitochondria of apoptotic cells. In addition, a number of catabolic enzymes are detected: arginase 1 (which degrades arginine), sulfite oxidase (which degrades sulfur amino acids), and epoxide hydrolase. Although the functional impact of each of these proteins on apoptosis remains elusive, the present data bank of mitochondrial proteins released upon PTPC opening should help further elucidation of the death process.
Assuntos
Apoptose , Permeabilidade da Membrana Celular , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/patologia , Proteínas/metabolismo , Sequência de Aminoácidos , Animais , Espectrometria de Massas , Camundongos , Dados de Sequência Molecular , Fragmentos de Peptídeos , Proteínas/químicaRESUMO
Inheritance of mitochondrial DNA (mtDNA) in Holstein cattle was characterized by pedigree analysis of nucleotide sequence variation. mtDNA was purified from leukocytes of 174 individuals representing 35 independent maternal lineages, and analyzed for nucleotide sequence variation by characterization of restriction fragment length polymorphism and direct sequence determination. These data revealed 11 maternal lineages in which leukocytes from some individuals seemingly were homoplasmic for the reference mtDNA sequence at nucleotide 364, whereas those from other individuals were homoplasmic for a sequence variant at this position. Both alternative alleles were detected in all branches of these 11 lineages, suggesting that mutation at nucleotide 364 and fixation of the variant sequence occurred frequently in independent events. Thirteen instances were detected of mother-daughter pairs in which leukocytes of each of the two animals seemingly were homoplasmic for a different allele at nucleotide 364, demonstrating the bovine mitochondrial genome can be replaced completely by a nucleotide sequence variant within a single generation. The two alternative sequences seemingly arose de novo at similar frequency, ruling out replicative advantage or other selective bias as the explanation for rapid fixation of mutations at nucleotide 364. Another instance of intralineage sequence variation was detected at nucleotide 5602. This variation was detected in only one of the lineages examined, and evidently arose within three generations.