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1.
Z Gerontol Geriatr ; 52(7): 688-693, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31049683

RESUMO

BACKGROUND: Sarcopenia and osteoporosis share an underlying pathology and reinforce each other in terms of negative outcomes. OBJECTIVE: To evaluate the extent of concomitance of sarcopenia as defined by the European Working Group on Sarcopenia in Older People (EWGSOP) and osteoporosis as defined by the World Health Organization (WHO) in geriatric inpatients and their relationship to nutritional and functional status. MATERIAL AND METHODS: A cross-sectional analysis of geriatric inpatients from the sarcopenia in geriatric elderly (SAGE) study. Measurements included dual X­ray absorptiometry for bone mineral density and appendicular muscle mass; gait speed and hand grip strength, the Barthel index, body mass index (BMI) and the mini nutritional assessment short form (MNA-SF). RESULTS: Of the 148 patients recruited for SAGE, 141 (84 women, 57 men; mean age 80.6 ± 5.5 years) had sufficient data to be included in this ancillary investigation: 22/141 (15.6%) were only osteoporotic, 19/141 (13.5%) were only sarcopenic and 20/141 (14.2%) osteosarcopenic (i.e. both sarcopenia and osteoporosis). The prevalence of osteoporosis was higher in sarcopenic than in non-sarcopenic individuals (51.3% vs. 21.6%, p < 0.001). Sarcopenic, osteoporotic and osteosarcopenic subjects had a lower BMI, MNA-SF, handgrip and gait speed (p < 0.05) than the reference group (those neither osteoporotic nor sarcopenic, n = 80). The Barthel index was lower for sarcopenic and osteosarcopenic (p < 0.05) but not for osteoporotic (p = 0.07) subjects. The BMI and MNA-SF were lower in osteosarcopenia compared to sarcopenia or osteoporosis alone (p < 0.05) while there were no differences in functional criteria. CONCLUSION: Osteoporosis and sarcopenia are linked to nutritional deficits and reduced function in geriatric inpatients. Co-occurrence (osteosarcopenia) is common and associated with a higher degree of malnutrition than osteoporosis or sarcopenia alone.


Assuntos
Osteoporose , Sarcopenia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Marcha , Força da Mão , Humanos , Masculino , Osteoporose/complicações , Osteoporose/epidemiologia , Prevalência , Sarcopenia/complicações , Sarcopenia/epidemiologia
2.
Age Ageing ; 48(5): 719-724, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31112221

RESUMO

INTRODUCTION: we examined the consequences of applying the new EWGSOP2 algorithm for sarcopenia screening instead of the former EWGSOP algorithm (EWGSOP1) in geriatric inpatients. METHODS: the dataset of our formerly published Sarcopenia in Geriatric Elderly (SAGE) study includes 144 geriatric inpatients (86 women, 58 men, mean age 80.7±5.6 years) with measurements of gait speed, handgrip strength and appendicular muscle mass by dual x-ray absorptiometry (DXA). We analysed the agreement between EWGSOP and EWGSOP2 algorithms in identifying patients as sarcopenic/non-sarcopenic. Differences in the distribution sarcopenic vs. non-sarcopenic were assessed by Chi²-test. RESULTS: sarcopenia prevalence according to EWGSOP1 (41 (27.7%)) was significantly higher than with EWGSOP2 (26(18.1%), p<0.05). The sex-specific sarcopenia prevalence was 22.1% (EWGSOP1) and 17.4% (EWGSOP2), respectively, for women (difference not significant) and 37.9% vs. 19.4% for men (p<0.05%). The overall agreement in classifying subjects as sarcopenic/non-sarcopenic was 81.25% (81.4% for women, 81.0% for men). However, among the 41 sarcopenia cases identified by EWGSOP1, only 20 (48.8%) were diagnosed with sarcopenia by EWGSOP2 (9/19 w (47.4%), 11/22 m (50.0%)). Ten of 19 women (52.6%) and 11 of 22 men (50.0%) diagnosed with sarcopenia by EWGSOP1 were missed by EWGSOP2, while 6 of 15 women (40.0%) and 0 of 11 men (0.0%) were newly diagnosed. DISCUSSION: there is a substantial mismatch in sarcopenia case finding according to EWGSOP1 and EWGSOP2. The overall prevalence and the number of men diagnosed with sarcopenia are significantly lower in EWGSOP2. While the absolute number of women identified as sarcopenic remains relatively constant, the overlap of individual cases between the two definitions is low.


Assuntos
Algoritmos , Marcha/fisiologia , Avaliação Geriátrica/métodos , Força da Mão/fisiologia , Pacientes Internados , Guias de Prática Clínica como Assunto , Sarcopenia/diagnóstico , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Áustria/epidemiologia , Diagnóstico Diferencial , Feminino , Humanos , Incidência , Masculino , Prevalência , Estudos Retrospectivos , Sarcopenia/epidemiologia , Sarcopenia/fisiopatologia
3.
Arch Gerontol Geriatr ; 80: 98-103, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30419483

RESUMO

BACKGROUND: Quantification of skeletal muscle mass is mandatory for diagnosing sarcopenia, a highly prevalent geriatric syndrome. While dual energy X-ray absorptiometry (DXA) is the reference method in a clinical context, bioimpedance analysis (BIA) is more readily applicable on a broad scale. Recently BIA equations for the prediction of appendicular skeletal muscle mass in higher age groups have been published, but data on their performance in geriatric inpatients are lacking. METHODS: In 144 geriatric inpatients (86 women and 58 men, mean age 80.7 ± 5.6 years) appendicular skeletal muscle mass was predicted by 4 different BIA equations and measured by DXA. Results were compared by linear regression analysis and Bland Altmann plots. The agreement with DXA in classifying subjects to have normal or reduced muscle mass was calculated for the BIA based approaches. RESULTS: The 4 BIA equations showed only minor differences in regression analysis, but major differences in mean error (range -0.98 kg to + 0.19 kg in women and -2.47 kg to -0.58 kg in men). Considering regression parameters and mean error, the equation of Scafoglieri et al. performed best, resulting in an agreement with DXA of more than 83%. Sensitivity to detect subjects with reduced muscle mass was <70% in the whole group for all BIA equations. CONCLUSION: The BIA equation of Scafoglieri et al. performs best in geriatric inpatients, with more than 83% of subjects classified correctly as having normal or reduced muscle mass compared to DXA. Low sensitivity to detect subjects with reduced muscle mass in geriatric inpatients remains a limitation of BIA.


Assuntos
Absorciometria de Fóton/métodos , Impedância Elétrica , Músculo Esquelético/patologia , Sarcopenia/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Composição Corporal/fisiologia , Feminino , Humanos , Masculino
4.
Biomed Res Int ; 2014: 351821, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24592386

RESUMO

The treatment of Parkinson's disease by transplantation of dopaminergic (DA) neurons from human embryonic mesencephalic tissue is a promising approach. However, the origin of these cells causes major problems: availability and standardization of the graft. Therefore, the generation of unlimited numbers of DA neurons from various types of stem or progenitor cells has been brought into focus. A source for DA neurons might be conditionally immortalized progenitor cells. The temperature-sensitive immortalized cell line CSM14.1 derived from the mesencephalon of an embryonic rat has been used successfully for transplantation experiments. This cell line was analyzed by unbiased stereology of cell type specific marker proteins and 2D-gel electrophoresis followed by mass spectrometry to characterize the differentially expressed proteome. Undifferentiated CSM14.1 cells only expressed the stem cell marker nestin, whereas differentiated cells expressed GFAP or NeuN and tyrosine hydroxylase. An increase of the latter cells during differentiation could be shown. By using proteomics an explanation on the protein level was found for the observed changes in cell morphology during differentiation, when CSM14.1 cells possessed the morphology of multipolar neurons. The results obtained in this study confirm the suitability of CSM14.1 cells as an in vitro model for the study of neuronal and dopaminergic differentiation in rats.


Assuntos
Diferenciação Celular , Mesencéfalo/citologia , Proteoma/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Animais , Contagem de Células , Linhagem Celular , Eletroforese em Gel Bidimensional , Humanos , Imuno-Histoquímica , Proteômica , Ratos
5.
J Med Primatol ; 40(3): 197-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21320132

RESUMO

BACKGROUND: Intra- and inter-species transmission of Human herpesvirus type 1 were noticed. In the present study, the herpesviral infection of a 1-year-old Azara's Night Monkey (Aotus azarae) was investigated. METHODS: Immunohistochemistry and electron microscopy investigations were done. RESULTS: A fatal systemic herpesviral infection was demonstrated. CONCLUSION: The results reveal the susceptibility of Azara's Night Monkey to the Human herpesvirus type 1. Moreover, humans shedding herpes viral particles during the reactivation phase of the infection directly infect the Azara's Night Monkeys.


Assuntos
Aotidae , Suscetibilidade a Doenças/veterinária , Herpes Simples/veterinária , Herpesvirus Humano 1/isolamento & purificação , Doenças dos Macacos/patologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Suscetibilidade a Doenças/diagnóstico , Suscetibilidade a Doenças/patologia , Suscetibilidade a Doenças/virologia , Evolução Fatal , Feminino , Herpes Simples/diagnóstico , Herpes Simples/patologia , Herpes Simples/virologia , Herpesvirus Humano 1/imunologia , Doenças dos Macacos/diagnóstico , Doenças dos Macacos/virologia
6.
Obes Rev ; 11(1): 92-100, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20653850

RESUMO

There is growing evidence that the glycaemic index (GI) of the diet is important with respect to body weight and metabolic disease risk. However, research is limited by the paucity of GI values for commonly consumed carbohydrate-rich foods in European countries. A new methodology has been developed for consistent assignment of GI values to foods across five European databases used in the Diogenes intervention study. GI values were assigned according to five decreasing levels of confidence (1) Measured values for specific foods; (2) Published values from published sources; (3) Equivalent values where published values for similar foods existed; (4) Estimated values assigned as one of three values representing low/medium/high GI ranges and (5) Nominal values assigned as 70, where no other value could be assigned with sufficient confidence. GI values were assigned to 5105 foods. In food records collected at baseline, the contribution to carbohydrate intake of foods assigned levels 1-2 ranged from 16% to 43% depending on country, and this increased to 53-81% including level 3 foods. The degree of confidence to assigned GI values differed across Europe. This standardized approach of assigning GI values will be made available to other researchers to facilitate further investigation into the effects of dietary GI on health.


Assuntos
Glicemia/metabolismo , Carboidratos da Dieta/classificação , Análise de Alimentos/métodos , Alimentos/classificação , Índice Glicêmico , Glicemia/análise , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/metabolismo , Europa (Continente) , Índice Glicêmico/fisiologia , Humanos
7.
Vet Pathol ; 47(4): 738-40, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20418472

RESUMO

Rhabdomyomas, defined as rare benign tumors of striated muscle, predominantly occur in the myocardium. In veterinary medicine, cardiac rhabdomyomas have rarely been reported but most frequently in pigs as an incidental finding. In the present case report, multiple circumscribed nodules found in the myocardium of 2 pigs were composed of large, vacuolated, glycogen-loaded cells. They expressed vimentin and desmin, neuron-specific enolase, and atrial natriuretic peptide. In addition, these cells expressed protein gene product 9.5, a marker for neuronal tissue and Purkinje fiber cells, in contrast to adjacent myocytes. The present findings-especially, the protein gene product 9.5 immunoreactivity-provide further evidence for the Purkinje fiber cell origin of the porcine myocardial proliferation. Therefore, the term purkinjeoma or purkinjeomatosis is proposed for cardiac rhabdomyoma in pigs.


Assuntos
Neoplasias Cardíacas/veterinária , Células de Purkinje/patologia , Rabdomioma/veterinária , Doenças dos Suínos/patologia , Animais , Biomarcadores Tumorais/metabolismo , Neoplasias Cardíacas/patologia , Imuno-Histoquímica/veterinária , Rabdomioma/patologia , Suínos , Terminologia como Assunto
8.
Epidemiol Infect ; 138(8): 1211-4, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20067659

RESUMO

Recurrence of peste des petits ruminants (PPR) was diagnosed in the United Arabian Emirates in several wild ruminants confirmed by morphological, immunohistochemical, serological and molecular findings. Phylogenetic analysis revealed that the virus strain belongs to lineage IV, which is different to some previously isolated PPR strains from the Arabian Peninsula. This study shows that wild ruminants may play an important epidemiological role as virus source for domestic small ruminants.


Assuntos
Animais Selvagens/virologia , Surtos de Doenças/veterinária , Peste dos Pequenos Ruminantes/veterinária , Vírus da Peste dos Pequenos Ruminantes/isolamento & purificação , Ruminantes/virologia , Animais , Análise por Conglomerados , Histocitoquímica , Fígado/patologia , Fígado/virologia , Oriente Médio/epidemiologia , Peste dos Pequenos Ruminantes/epidemiologia , Peste dos Pequenos Ruminantes/virologia , Vírus da Peste dos Pequenos Ruminantes/genética , Filogenia
9.
Obes Rev ; 11(1): 67-75, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19573053

RESUMO

The aim of this study was to describe the development and implementation of a multifaceted, low-fat, weight-loss strategy for a Pan-European randomized controlled dietary intervention study, Diogenes. There were 891 families with at least one overweight/obese parent who underwent screening. Eligible, overweight/obese adults followed an 8-week weight-loss phase with a fixed low-energy diet (800 kcal). On attaining weight loss of > or = 8%, families were randomized to a 6- or 12-month low-fat (25-30%E) diet either based on national dietary guidelines or one of four interventions: low protein (LP)/low glycaemic index (LGI), LP/high GI (HGI), high protein (HP)/LGI and HP/HGI. The impact of each diet in preventing weight (re)gain was tested. A points-based system was used to manipulate dietary protein and carbohydrate. Manipulating carbohydrate composition involved substituting foods with a relatively high or low GI. A questionnaire was designed and completed by study investigators, providing feedback on the dietary intervention methods used to inform future interventions. The points system allowed macronutrient manipulations without compromising dietary flexibility or enforcing energy restrictions. Reported centre/participant differences in the ease of implementing the intervention may reflect dietary diversity and personal preferences for specific weight-management strategies. The points system provides a useful starting point for designing improved experimental paradigms for the manipulation of dietary intake in future trials.


Assuntos
Dieta Redutora , Índice Glicêmico , Obesidade/dietoterapia , Redução de Peso , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Comparação Transcultural , Dieta com Restrição de Carboidratos , Dieta com Restrição de Gorduras , Dieta com Restrição de Proteínas , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/classificação , Carboidratos da Dieta/metabolismo , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Neuropathol Appl Neurobiol ; 34(6): 603-20, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18466224

RESUMO

AIMS: Limited remyelination is a key feature of demyelinating Theiler's murine encephalomyelitis (TME). It is hypothesized that a dysregulation of differentiation of oligodendroglial progenitor cells (OPCs) represents the main cause of insufficient regeneration in this model of multiple sclerosis. METHODS: TME virus (TMEV)-infected SJL/J mice were evaluated by footprint analysis, light and electron microscopy, immunohistology, confocal immunofluorescence and RT-qPCR at multiple time points ranging from 1 h to 196 days post infection (dpi). RESULTS: Footprint analysis revealed a significantly decreased stride length at 147 and 196 dpi. Demyelination progressively increased from 14 towards 196 dpi. A mild amount of remyelination was detected at 147 and 196 dpi. Early onset axonal injury was detected from 14 dpi on. TMEV RNA was detectable throughout the observation period and markedly increased between 7 and 28 dpi. Intralesional nerve/glial antigen 2 (NG2)-positive OPCs were temporarily increased between 28 and 98 dpi. Similarly, a transient upregulation of NG2 and platelet-derived growth factor alpha-receptor mRNA was noticed. In contrast, intralesional 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase)-positive oligodendrocytes were decreased between 56 and 196 dpi. Although CNPase mRNA remained unchanged, myelin basic protein mRNA and especially its exon 2 containing splice variants were decreased. Glial fibrillary acidic protein (GFAP)-positive astrocytes and GFAP mRNA were increased in the late phase of TME. A mildly increased colocalization of both NG2/CNPase and NG2/GFAP was revealed at 196 dpi. CONCLUSIONS: Summarized, the present results indicated a dysregulation of OPC maturation as the main cause for the delayed and limited remyelination in TME. A shift of OPC differentiation from oligodendroglial towards astrocytic differentiation is postulated.


Assuntos
Antígenos/metabolismo , Infecções por Cardiovirus/fisiopatologia , Encefalomielite/fisiopatologia , Esclerose Múltipla/fisiopatologia , Bainha de Mielina/fisiologia , Proteoglicanas/metabolismo , Células-Tronco/citologia , Theilovirus , 2',3'-Nucleotídeo Cíclico Fosfodiesterases/genética , 2',3'-Nucleotídeo Cíclico Fosfodiesterases/metabolismo , Animais , Antígenos/genética , Infecções por Cardiovirus/patologia , Infecções por Cardiovirus/virologia , Diferenciação Celular , Encefalomielite/patologia , Encefalomielite/virologia , Feminino , Expressão Gênica , Proteína Glial Fibrilar Ácida , Imuno-Histoquímica , Camundongos , Microscopia Confocal , Microscopia Eletrônica , Microscopia de Fluorescência , Esclerose Múltipla/patologia , Proteína Básica da Mielina/genética , Proteína Básica da Mielina/metabolismo , Bainha de Mielina/patologia , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Oligodendroglia/citologia , Oligodendroglia/fisiologia , Proteoglicanas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Medula Espinal/virologia , Células-Tronco/fisiologia , Theilovirus/isolamento & purificação
11.
J Cell Mol Med ; 12(5A): 1661-71, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18088383

RESUMO

G(M1)-gangliosidosis is a lysosomal storage disorder caused by a deficiency of ss-galactosidase activity. Human GM1-gangliosidosis has been classified into three forms according to the age of clinical onset and specific biochemical parameters. In the present study, a canine model for type II late infantile human GM1-gangliosidosis was investigated 'in vitro' in detail. For a better understanding of the molecular pathogenesis underlying G(M1)-gangliosidosis the study focused on the analysis of the molecular events and subsequent intracellular protein trafficking of beta-galactosidase. In the canine model the genetic defect results in exclusion or inclusion of exon 15 in the mRNA transcripts and to translation of two mutant precursor proteins. Intracellular localization, processing and enzymatic activity of these mutant proteins were investigated. The obtained results suggested that the beta-galactosidase C-terminus encoded by exons 15 and 16 is necessary for correct C-terminal proteolytic processing and enzyme activity but does not affect the correct routing to the lysosomes. Both mutant protein precursors are enzymatically inactive, but are transported to the lysosomes clearly indicating that the amino acid sequences encoded by exons 15 and 16 are necessary for correct folding and association with protective protein/cathepsin A, whereas the routing to the lysosomes is not influenced. Thus, the investigated canine model is an appropriate animal model for the human late infantile form and represents a versatile system to test gene therapeutic approaches for human and canine G(M1)-gangliosidosis.


Assuntos
Gangliosidose GM1/enzimologia , Processamento de Proteína Pós-Traducional , beta-Galactosidase/metabolismo , Animais , Animais Geneticamente Modificados , Células Cultivadas , Modelos Animais de Doenças , Cães , Gangliosidose GM1/genética , Gangliosidose GM1/patologia , Humanos , Mutação/genética , beta-Galactosidase/deficiência , beta-Galactosidase/genética
12.
Arch Virol ; 153(1): 187-92, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17896075

RESUMO

European harbour seal (Phoca vitulina) populations decreased substantially during the phocine distemper virus (PDV) outbreaks of 1988 and 2002. Different hypotheses have stated that various seals and terrestrial carnivore species might be the source of infection. To further analyse these hypotheses, grey (Halichoerus grypus) and ringed (Phoca hispida) seals, polar bears (Ursus maritimus) and minks (Mustela lutreola) were sampled from the North Sea and East Greenland coasts between 1988 and 2004 and investigated by RT-PCR using a panmorbillivirus primer pair. However, all samples were negative for morbillivirus nucleic acid.


Assuntos
Surtos de Doenças/veterinária , Vírus da Cinomose Focina/patogenicidade , Cinomose/epidemiologia , Phoca/virologia , Animais , Primers do DNA , Reservatórios de Doenças/veterinária , Vetores de Doenças , Cinomose/mortalidade , Cinomose/patologia , Europa (Continente)/epidemiologia , Morbillivirus/classificação , Morbillivirus/patogenicidade , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Artigo em Inglês | MEDLINE | ID: mdl-16837253

RESUMO

As the pathogenesis of the HELLP-syndrome is unknown, a complex consideration regarding the changes in the plasma as the main transport medium in the body is of great benefit because it is well available and can rapidly be investigated in the clinics. Besides that, the liver which is early affected in HELLP-syndrome produces the main part of plasma proteins. For the purpose of our study plasma protein abundances from patients with HELLP-syndrome and from control individuals were determined before and after delivery. In the differential analysis using two-dimensional gel electrophoresis, six areas with variable protein spot intensities were detected. The reference gel that we developed for HELLP plasma samples integrates the changes of plasma proteins when comparing HELLP patients to healthy women prior to and after delivery. A specific plasma protein profile for the HELLP-syndrome was generated involving protein areas that contain inter-alpha-trypsin inhibitor heavy chain H4, kininogen 1, fibrinogen gamma chain, transthyretin, haptoglobins, and serum amyloid A with statistically significant expression differences when compared to controls. The most striking difference between the majority of the gels from HELLP patients and the gels from non-HELLP samples were clearly overexpressed protein spots at about 11 kDa which were identified as serum amyloid A (SAA). This differential expression was validated and quantitatively assayed by ELISA measurements against human SAA in plasma. Our results show that significant differences in SAA expressions between healthy controls and HELLP patients were obtained, that could function as markers for the HELLP-syndrome. According to our data it is possible to draw a line of separation with no overlap between the HELLP group for which SAA plasma levels were found to be above 3.51 mg/L and the non-HELLP groups in which SAA plasma levels were below 3.51 mg/L. It now is possible to clinically elucidate if the differentially expressed proteins are suited for longitudinal studies concerning both, to function as markers or perhaps even as disease predictors that might become relevant for diagnostic tests.


Assuntos
Biomarcadores/metabolismo , Síndrome HELLP/metabolismo , Proteoma , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Gravidez , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
14.
Biotechnol Bioeng ; 93(2): 238-45, 2006 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-16267850

RESUMO

Monolith reactors combine good mass transfer characteristics with low-pressure drop, the principle factors affecting the cost effectiveness of industrial processes. Recently, these specific features of the monolith reactors have drawn the attention toward the application of the monolith reactor in multiphase reaction systems. In this study, we explore the potential application of monolith reactors as bioreactor requiring gas-liquid mass transfer for substrate supply. It is demonstrated on theoretical grounds that the monolith reactor is a competitive alternative to conventional gas-liquid bioreactors such as stirred tanks, packed beds, and airlift bioreactors because it allows for a significant reduction of the energy dissipation that is normally required for gas-liquid contacting. A potential problem of monolith reactors for biological processes is clogging due to biofilm formation. This paper presents experimental results of a study into the formation and possible removal of biofilms during operation of a monolith reactor as suspended cells bioreactor. The results indicate that biofilm formation may be minimized and postponed by a proper choice of operating conditions. Periodic biofilm removal could straightforwardly be achieved by rinsing with water at moderate pressures and allows for stable operation for prolonged periods of time.


Assuntos
Biofilmes , Reatores Biológicos , Biotecnologia/instrumentação
15.
J Neurobiol ; 56(4): 303-14, 2003 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-12918015

RESUMO

Bird song is a model for studying neural control and lateralization of a learned behavior. Adult male canary develops large and varied song repertoires. Particular features of the male are well known to stimulate the reproductive activities of the female. We report here on the effect of lesions of either the left or right HVC, a key nucleus of the descending vocal control network of songbirds, on different song parameters of common domesticated male canaries of an European outbred strain. These canaries are useful to evaluate the question of central versus peripheral lateralization because they do not show syringeal dominance for syllable production compared to the previously studied canary strains. Right-sided lesions reduced the highest frequency and the widest frequency band. Left-sided lesion increased the lowest frequency. The size of the left-sided lesions correlated with the reduction of the repertoire of simple syllables, of the total repertoire and of the highest repetition rate, and with the increase of the lowest frequency. These results suggest a lateralized specialization of both left and right vocal pathways for particular features of the song, especially those that are known to elicit a great number of copulation solicitation displays (CSD). Lesions of both left and right pathways affected, however, sound amplitude of all syllables. Because this effect was more sever following left-sided lesions, and because the syrinx morphology of canaries has a left-right asymmetry, we suggest a peripheral mechanism for the observed lateralized specializations.


Assuntos
Encéfalo/fisiologia , Canários/fisiologia , Lateralidade Funcional/fisiologia , Vocalização Animal/fisiologia , Animais , Feminino , Masculino , Espectrografia do Som/métodos
16.
J Neurobiol ; 52(1): 1-13, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12115889

RESUMO

The courtship solicitation display (CSD) of the female canary is a model to study estrogen dependent auditory preferences for male songs. The forebrain auditory-vocal nucleus, HVC, is part of the circuit that determines such preferences. To further develop this model we show that bilateral excitotoxic lesions of the medial part of HVC involving between 18-60% of the bilateral nucleus are behaviorally effective while complete unilateral lesions are not. Further, we show that animals recover their song preferences over a period of several months after the lesion. This functional recovery does not involve anatomical recovery of the HVC. Even 9 months after the lesion, the HVC size of these females was similar to that of females sacrificed 2 days after the lesion and thus was 40 +/- 8% smaller compared to normal females. Further, ipsilaterally, the lesion procedure transiently disturbed the neurochemistry, such as GAD-mRNA expression, in the part of HVC that did not undergo cell death. These results suggest that the integrity of the lateral part of at least one HVC is required to perform CSD in response to relevant auditory stimuli.


Assuntos
Canários/fisiologia , Telencéfalo/fisiologia , Vocalização Animal/fisiologia , Animais , Química Encefálica/fisiologia , Cognição/fisiologia , Copulação/fisiologia , Denervação , Feminino , Lateralidade Funcional/fisiologia , Glutamato Descarboxilase/genética , Neurotoxinas , RNA Mensageiro/análise , Receptores Androgênicos/genética , Recuperação de Função Fisiológica/fisiologia , Telencéfalo/anatomia & histologia
17.
Clin Rev Allergy Immunol ; 20(3): 357-83, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11413904

RESUMO

Acute severe asthma calls for aggressive and early therapy of a multifaceted and all-inclusive approach (Fig. 2). Therapy merely begins in the ED and manifold distinct issues need to find consideration during ongoing hospital care. Currently, beta-agonists, anti-cholinergic agents, and corticosteroids remain the mainstay of therapy. Methylxanthines and magnesium may find consideration in carefully selected patients. Multiple new therapeutic avenues, such as the anti-leukotriene drugs, seem promising and future studies will hopefully extend our armamentarium against life threatening complication of a common disease. Asthma education begun in the hospital may provide the platform for preventing severe acute exacerbations and hospitalization.


Assuntos
Asma/tratamento farmacológico , Hospitalização , Doença Aguda , Adolescente , Adulto , Fatores Etários , Asma/mortalidade , Asma/fisiopatologia , Criança , Pré-Escolar , Serviços Médicos de Emergência , Humanos , Estados Unidos/epidemiologia
18.
Horm Behav ; 38(2): 123-9, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10964526

RESUMO

We studied copulation solicitation display (CSD) responses to playback in photostimulated female canaries given systemic injections of progesterone. Eight females received injections of 0.1 mg of progesterone dissolved in olive oil during their first breeding cycle and were untreated during their second breeding cycle; eight females received only the oil vehicle during their first breeding cycle and received no treatment during their second breeding cycle. The injections were performed every second day during 15 days, after the onset of nest building. Progesterone treatment resulted in a significant increase of plasma progesterone which in turn provoked an inhibition of females' CSDs and decreased the size of the clutch. During the first breeding cycle, progesterone-treated females had lower CSDs and egg-laying scores than did control females. During the second breeding cycle, when females received no treatment, no differences emerged between the two groups. The suppressive effect of progesterone on female sexual responses was observed as soon as 48 h after the beginning of the treatment. We propose that progesterone plays a key role in mediating the transition from active female courtship behavior to sexual refractoriness in this species. Suppressive effects of progesterone on female sexual behavior have been previously described in lizards as well as in rodents. Our data are consistent with the hypothesis of Godwin et al. (J. Godwin, V. Hartman, M. Grammer, and D. Crews, Horm. Behav. 30, 138-144, 1996) which proposed that the decrease in sexual behavior following plasma progesterone increase represents an evolutionarily conserved mechanism in the regulation of female sexual behavior.


Assuntos
Canários/fisiologia , Progesterona/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Animais , Feminino , Oviposição/efeitos dos fármacos , Oviposição/fisiologia
19.
Behav Neurosci ; 114(3): 526-42, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10883803

RESUMO

During the breeding season under long-day conditions, male canaries sing sexually attractive songs and females respond behaviorally to such songs. This study assessed whether auditory response properties of neurons in nucleus HVc of female and male canaries are tuned to sexually salient song features: special song phrases and canary song segmentation. In sexually receptive female canaries, neurons responded to special song phrases with a decreased spike rate and were sensitive to canary song segmentation. The nonreceptive females showed no clear response to special song phrases. In females on short days, neurons responded to song phrases with an increase in activity. In males on long days, they exhibited phasic responses after the phrase onset, whatever the song phrase and song segmentation. This study demonstrates both a plasticity in relation to females' sexual responsiveness and a sexual dimorphism in the auditory processing performed in the HVc.


Assuntos
Encéfalo/fisiologia , Canários/fisiologia , Comportamento Sexual Animal/fisiologia , Vocalização Animal/fisiologia , Animais , Mapeamento Encefálico , Potenciais Evocados Auditivos/fisiologia , Feminino , Masculino , Plasticidade Neuronal/fisiologia , Receptores de Estrogênio/fisiologia , Estações do Ano , Espectrografia do Som
20.
Behav Processes ; 46(2): 151-8, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24895847

RESUMO

Both hybridization and competition may induce character shift on communication systems in hybrid zones, leading either to convergence or divergence. Melodious warblers Hippolais polyglotta and Icterine warblers H. icterina are interspecifically territorial and hybridize along a narrow contact zone. This spatial distribution is favoured by a reaction to the congeneric song. A character displacement, e.g. a decrease of the reaction, was expected within the hybrid zone because of reproduction costs lower than in allopatry. We investigated the pattern of variation of the interspecific reaction by comparing allopatric and sympatric populations. However, our data did not support the hypothesis character displacement and we propose several alternatives to account for the maintenance of interspecific reaction in sympatry.

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