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1.
J Appl Microbiol ; 105(2): 459-68, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18298524

RESUMO

AIMS: The objective of this study was to develop a novel synthetic growth medium for increased conidium production of the entompathogenic fungus Metarhizium anisopliae. The medium should simulate natural nutritional conditions. METHODS AND RESULTS: Macro- and micronutrients were selected in concentrations found in insects or from sources which are believed to be advantageous for virulence. Medium development was guided by a problem-oriented genetic algorithm (GA) implemented with 'mutation' and 'recombination' operators specific for this optimization problem. Following five optimization steps and a total of 181 medium variations, 19 synthetic media led to increased conidium production as compared with the standard Sabouraud dextrose agar medium: increases in conidia yields of up to 120% and a 17-fold higher conidium production per square centimetre of mycelium were achieved. Rapid germination of conidia, conidial C : N ratio, as well as spore-bound Pr1 protease production were monitored as proposed quality control markers for a virulent inoculum. CONCLUSIONS: It was demonstrated that our problem-oriented GA is a powerful tool for the design of chemically defined cultivation media with special/enhanced properties for anamorphic fungi. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study, which demonstrates the advantage of the use of a GA for the rapid design of solid synthetic media for maximum production of virulent conidia.


Assuntos
Algoritmos , Metarhizium/crescimento & desenvolvimento , Modelos Genéticos , Micologia/métodos , Microbiologia do Solo , Meios de Cultura , Alimentos
2.
J Appl Microbiol ; 105(6): 2026-34, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18713285

RESUMO

AIMS: Synthetic media should be designed for the production of Metarhizium anisopliae conidia with improved virulence properties. METHODS AND RESULTS: A genetic algorithm (GA), demonstrated to be suitable for the design of media for spore mass production (Hutwimmer et al. 2008), was utilized for a multi-objective medium design to improve conidia yield and three proposed virulence properties of conidia: C : N ratio, germination speed and amount of spore-bound Pr1 protease. After five iterative optimizations, 52 media were improved over Sabouraud dextrose agar (SDA). Four media exhibited medium performances (a factor derived from the four single optimization variables) of around 0.7; cf. SDA = 0.532; media with enhanced properties were reached for each single optimization variable; Bioassays against Tenebrio larvae indicated also a slight improvement in virulence of conidia from designed media. A degenerated phenotype of the same strain did not exhibit differences in colony appearance, spore characteristics and virulence if grown on designed media. CONCLUSIONS: The application of a problem-oriented GA is a practical and rapid method to design media for multi-objective purposes. SIGNIFICANCE AND IMPACT OF THE STUDY: The applicability of a GA for multi-objective medium design was demonstrated for the cultivation of anamorphic fungi on solid media.


Assuntos
Algoritmos , Meios de Cultura/química , Metarhizium/crescimento & desenvolvimento , Modelos Genéticos , Esporos Fúngicos/fisiologia , Micologia/métodos , Nitrogênio/metabolismo
3.
FEMS Microbiol Lett ; 119(3): 365-70, 1994 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-8050718

RESUMO

The complex-forming compound oxalic acid can effectively solubilise metals such as aluminium, iron, lithium and manganese. In order to produce high amounts of oxalic acid for biohydrometallurgical processes, it was the aim of this work to optimise oxalic acid production by Aspergillus niger, a fungus well known for its ability to produce oxalic acid. A. niger excreted 427 mmol oxalic acid l-1 if it was cultivated in a pH-controlled (pH 6.0) fed-batch run in a 2-l stirred tank reactor. Sucrose and lactose permeate were suitable carbon sources for oxalic acid production. In sucrose medium, A. niger produced high amounts of gluconic and oxalic acids, whereas in lactose permeate medium only oxalic acid was produced. Cultivation in green syrup and molasses media lead to high yields of biomass, but low oxalic acid production (< 20 mmol l-1).


Assuntos
Aspergillus niger/metabolismo , Oxalatos/metabolismo , Meios de Cultura/química , Concentração de Íons de Hidrogênio , Microbiologia Industrial/métodos , Ácido Oxálico , Sacarose
4.
Urology ; 47(4): 485-90, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8638355

RESUMO

OBJECTIVES: This study was undertaken to evaluate the efficacy of three-dimensional transrectal ultrasound to identify and measure the prostate zones. METHODS: In an anatomic-sonographic study, eight specimens were investigated by means of three-dimensional transrectal ultrasound. Subsequently, the volumes of the prostate and the transition zone were measured by means of a special planimetric program; the images and results obtained were compared with anatomic sections and water displacement volume measurement. Then two groups of patients were investigated by means of three-dimensional transrectal ultrasound; the first group included 90 patients ranging in age from 55 to 85 years who presented with benign prostatic hyperplasia (BPH), which was verified by means of histologic examination. Three-dimensional transrectal ultrasound was performed prior to ultrasound-guided biopsies of the prostate. The second group comprised 10 patients aged between 17 and 30 years whose prostates were free of disease. RESULTS: Three-dimensional transrectal sonography is the first imaging technique that can simultaneously demonstrate relevant structures in three planes; apart from the sagittal and the horizontal (or axial) plane, the region of interest can be examined in the coronal plane as well. The structural differences of the prostatic zones in BPH and the juvenile gland can be clearly identified with the help of three-dimensional transrectal ultrasound. The coronal plane provides important additional information; the central zone and the enlarged transition zone can be identified best in this third plane. CONCLUSIONS: The prostate zones, their interrelations, and, in particular, the hyperplasia of the transition zone in BPH are clearly demonstrable. Furthermore, the size of the enlarged transition zone can be exactly measured.


Assuntos
Próstata/anatomia & histologia , Próstata/diagnóstico por imagem , Hiperplasia Prostática/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/patologia , Ultrassonografia
5.
Urology ; 46(5): 662-5, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7495117

RESUMO

OBJECTIVES: This study was designed to compare the usefulness of the normal prostate-specific antigen (PSA) level and the age-referenced PSA level in a large screening study for early detection of prostate cancer. METHODS: A total of 21,078 subjects (aged 45 to 75 years) were participants in a 1-year prostate cancer screening project with PSA as the initial test. Of the volunteers, 1618 (8%) showed an elevated PSA level according to age-specific reference ranges, and using the normal PSA cutoff point (4.0 ng/mL), 1872 (9%) had elevated PSA levels between 4.0 and 6.5 ng/mL. RESULTS: Biopsies in both groups were performed if the PSA level was elevated. We evaluated the effect on biopsy rate and cancer detection. A PSA cutoff point of 2.5 ng/mL in men 45 to 49 years old and a PSA cutoff point of 3.5 ng/mL in men 50 to 59 years old with normal digital rectal examination findings resulted in an 8% increase in the number of biopsies (66 of 778) and an 8% increase in organ-confined cancer detection. An increasing cutoff of 4.5 ng/mL in men 60 to 69 years old and 6.5 ng/mL in men 70 to 75 years old resulted in 21% fewer biopsies (205 of 983) and would have missed 4% of organ-confined tumors (8 of 220). CONCLUSIONS: We conclude that the use of PSA age-specific reference ranges increases the detection of clinically important and organ-confined cancers in young men and decreases the number of biopsies in older men.


Assuntos
Programas de Rastreamento , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico , Idoso , Biópsia , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fatores de Tempo
6.
Urology ; 48(6A Suppl): 62-6, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8973702

RESUMO

OBJECTIVES: Two different studies were performed. The aim of the first study was to define whether the measurement of the ratio between free and total prostate-specific antigen (f/t PSA) in serum may enhance the ability of PSA-based screening for early detection of prostate cancer in men with elevated serum PSA levels. A second study was undertaken to investigate the value of f/t PSA ratio in serum to improve the specificity of prostate cancer screening in men with serum PSA levels between 2.5 and 10.0 ng/mL. METHODS: In a retrospective study of 266 men with elevated PSA levels and proven biopsy results, f/t PSA levels were measured using deep frozen serum samples. In a second study we enrolled 158 men with elevated PSA levels according to age reference ranges apparent from our current PSA screening study with additional measurement of the f/t PSA ratio. All study volunteers with a free f/t PSA ratio cutoff point of < or = 22% underwent digital rectal examination, transrectal ultrasonography, and biopsy of the prostate. Free and total PSA levels were measured with the Delfia PSA dual label f/t PSA kit (Wallac Oy Turku, Finland). RESULTS: 106 of 158 men with elevated total PSA values between 2.5 and 10.0 ng/mL (group 1) have been further evaluated and 37 prostate cancers were detected. Mean percentage of free PSA was 10% in men with cancer and 22% in men with benign prostatic hyperplasia. Using a f/t PSA ratio of < or = 22% as a biopsy criterion 30% of the negative biopsies could be eliminated while still detecting 98% carcinomas. CONCLUSIONS: Measurement of f/t PSA reduces the number of unnecessary biopsies in PSA screening without missing many cancers.


Assuntos
Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Idoso , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/prevenção & controle , Curva ROC , Estudos Retrospectivos
7.
J Exp Psychol Anim Behav Process ; 26(3): 323-39, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10913996

RESUMO

This study examined contextual control of long-term habituation and whether such effects are dependent on the habituating response system. Habituation of the acoustic startle response transferred from the home cage to the testing context, whereas habituation of lick suppression was context specific (Experiments 1 and 2). Contextual control of habituation was demonstrated between 2 experimental contexts for lick suppression to a tone (Experiment 3) and bar-press suppression to a light (Experiment 4). Experiment 5 extinguished habituation of lick suppression and the orienting response to a tone with 27 exposures to the habituation context. Context specificity of both responses also was found. Previous failures to demonstrate contextual control of habituation may be due to the choice of response system and to less sensitive procedures to detect response recovery. The habituation mechanism for startle is independent from the process or processes that underlie habituation in other response systems, but the nature of these mechanisms is not yet known.


Assuntos
Comportamento Animal , Asseio Animal , Habituação Psicofisiológica , Ratos Sprague-Dawley/psicologia , Reflexo de Sobressalto , Estimulação Acústica , Animais , Sinais (Psicologia) , Meio Ambiente , Extinção Psicológica , Feminino , Inibição Psicológica , Masculino , Estimulação Luminosa , Ratos
8.
J Endourol ; 9(6): 497-501, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8775083

RESUMO

In recent years, interstitial laser therapy was introduced to provide a new treatment of benign prostatic hyperplasia (BPH). However, the precise positioning of the laser fibers has remained a major unsettled issue. Three-dimensional (3-D) transrectal ultrasound scanning permits precise differentiation of the prostatic zones, in particular the transition zone, which is enlarged in BPH. Initially, a volume scan of the prostate is obtained. On the monitor, three sections of the prostate in the coronal, sagittal, and horizontal planes are displayed simultaneously. This new 3-D technology enables precise and reproducible positioning of the laser fibers at any selected site in the adenoma under sonographic guidance, thus providing the basis for complete laser prostatectomy. Placement of the laser fibers proved to be precise, quick, and uncomplicated.


Assuntos
Terapia a Laser/métodos , Hiperplasia Prostática/terapia , Ultrassonografia de Intervenção , Humanos , Masculino , Necrose , Hiperplasia Prostática/patologia , Reprodutibilidade dos Testes
9.
Noise Health ; 5(20): 75-84, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14558895

RESUMO

In order to investigate whether the energy-equivalence principle is at least acceptable for exposures with a duration in the range of hours and in order to disclose the actual physiological responses to exposures which varied with respect to the time structure and the semantic quality of sounds, a series of tests was carried out where physiological costs associated with varying exposures were measured audiometrically. In a cross-over test design, 10 Subjects (Ss) participated in test series with 3 energetically equal sound exposures on different days. The exposures corresponded with a tolerable rating level of 85 dB / 8 h. In a first test series (TS I), the Ss were exposed to a prototype of industrial noise with a sound pressure level of 94 dB(A) / 1 h. In a second test series (TS II), the same type of noise was applied, but the exposure time of a reduced level of 91 dB(A) was increased to 2 hours. In a third test series (TS III), classical music was provided also for 2 h at a mean level of 91 dB(A). The physiological responses to the 3 exposures were recorded audiometrically via the temporary threshold shift TTS2, the restitution time t(0 dB), and the IRTTS-value. IRTTS is the integrated restitution temporary threshold shift which is calculated by the sum of all threshold shifts. It represents the total physiological costs the hearing must "pay" for the sound exposure. Physiological responses of the hearing to the industrial noise exposures in TS I and TS II, all in all, were identical in the 3 parameters. Maximum threshold shifts of approximately 25 dB occurred which did not dissipate completely until 2.5 h after the end of the exposure and IRTTS-values of about 800 dBmin were calculated. Therefore, at least for exposure times in the range of hours, the equilibration of intensity and duration of sound exposures according to the energy-equivalence principle seems to have no influence on the hearing. Classical music was associated with the least severe TTS of less than 10 dB which disappeared much more quickly. IRTTS added up to just about 100 dBmin and, in comparison with 800 dBmin as specific responses to industrial noise, amounted to only about 12%. The substantially lower physiological costs of classical music apparently indicate a decisive influence of the type of sound exposures. Making inferences from the results of the study, the conventional approach of rating sound exposures exclusively by the principle of energy equivalence can lead to gravely misleading assessments of their actual physiological costs.


Assuntos
Limiar Auditivo/fisiologia , Ruído , Adulto , Audiometria , Limiar Auditivo/classificação , Feminino , Humanos , Masculino , Música
10.
Urologe A ; 43(2): 128-32, 2004 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-14991112

RESUMO

To reach an optimal outcome after radical prostatectomy or cystoprostatectomy, minimal bleeding from the dorsal vein complex, meticulous apical dissection without distraction of the rhabosphincter and preservation of the cavernous nerves are necessary.A total of 19 male cadavers were used, ranging in age from 52-78 years and including 8 fetuses. Fourteen complete pelves and five tissue blocks of prostate, rectum, membranous urethra and the rhabdosphincter were investigated. Besides anatomical preparations, the lower urinary tract was studied by means of serial histological sections. The cavernous nerves and the pudendal nerves as well as their branches were dissected. For this reason, the pubic symphysis was severed. Subsequently the right or left hip bone was removed, whereas the pelvic organs were left intact to achieve a complete exposure of the lower urinary tract and the pudendal nerves. The rhabdosphincter presents as a vertical structure extending from the bulb of the penis to the region of the bladder neck along the prostate and the membranous urethra. It is supplied by branches of the pudendal nerve after leaving the pudendal canal. The membranous urethra is innervated by branches of the autonomic pelvic plexus. The nervous branches that are responsible for erection travel along the lateral aspects of the prostate in the so called "neurovascular bundle" and traverse through the urogenital hiatus to reach the corpora cavernosa.


Assuntos
Pelve/anatomia & histologia , Pelve/inervação , Próstata/anatomia & histologia , Próstata/inervação , Reto/anatomia & histologia , Reto/inervação , Uretra/anatomia & histologia , Uretra/inervação , Idoso , Animais , Cadáver , Humanos , Masculino , Pessoa de Meia-Idade
11.
Urologe A ; 33(1): 3-8, 1994 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-8146928

RESUMO

In the past few years great effort has been made to reduce the morbidity after oncologic operations in the small pelvis of the male. In this respect it is essential for urologic surgeons to orient themselves with the anatomic structures that mark the course of the important vessels and nerves. For this reason an anatomic study of the connective tissue in the male pelvis was performed in which dissections and serial sections were analyzed. The results show that the connective tissue in the male pelvis does not represent a monomorphic block but consists of several portions of varying density. The looser portions are also known as the "connective tissue spaces" of the pelvis. The comparatively dense portions--the so-called "vessel-nerve guiding plate" and its three "connective tissue pillars"--envelop the vessels and nerves supplying the corresponding pelvic organs. Therefore, they provide ideal landmarks for urologic surgery.


Assuntos
Ereção Peniana/fisiologia , Pênis/irrigação sanguínea , Pênis/inervação , Instrumentos Cirúrgicos , Neoplasias Urogenitais/cirurgia , Adulto , Artérias/patologia , Artérias/cirurgia , Tecido Conjuntivo/patologia , Tecido Conjuntivo/cirurgia , Cistectomia/instrumentação , Fáscia/patologia , Fasciotomia , Humanos , Masculino , Nervos Periféricos/patologia , Nervos Periféricos/cirurgia , Prostatectomia/instrumentação , Neoplasias Urogenitais/patologia , Veias/patologia , Veias/cirurgia
12.
Urologe A ; 43(2): 141-49, 2004 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-14991114

RESUMO

Traditionally, oncological factors have been the only ones used in the evaluation of treatment outcome for urological tumor patients. With increased diagnoses of early, curable tumors in younger individuals, health-related quality of life and functional aspects are gaining importance. Sexual and urinary function are significant aspects of quality of life, which are especially vulnerable in urological patients. New insights into the anatomy and physiology of the pelvic organs have resulted in an improvement in surgical therapy. In this article, we present the results of current experimental and clinical studies, which underline the importance of nerve sparing techniques for maintaining a satisfying urinary and sexual function in this patient population.


Assuntos
Disfunção Erétil/prevenção & controle , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Avaliação de Processos e Resultados em Cuidados de Saúde/métodos , Neoplasias Pélvicas/cirurgia , Pelve/inervação , Pelve/cirurgia , Qualidade de Vida , Incontinência Urinária/prevenção & controle , Animais , Disfunção Erétil/etiologia , Feminino , Humanos , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Neoplasias Pélvicas/complicações , Traumatismos dos Nervos Periféricos , Complicações Pós-Operatórias , Incontinência Urinária/etiologia
13.
Urologe A ; 43(11): 1371-6, 2004 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-15583899

RESUMO

In 3-D transrectal ultrasound it is possible, for the first time, to investigate the region of interest in three planes simultaneously. Exact examination of the organs of the small pelvis as well as of pathologic changes in the region of the pelvic floor can be performed with this new imaging technique. The bulbourethral glands can be investigated routinely, which enables the diagnosis of cysts of these glands. The prostatic zones, their relations as well as the growth of the transitional zone during the development of benign prostatic hyperplasia can be visualized. Furthermore, 3-D transrectal ultrasound allows investigation of morphology and function of the rhabdosphincter. The contractility of the muscle can be quantified. 3-D ultrasound guided puncture and drainage of prostatic abscesses represents a minimally invasive therapeutic modality. This technique can be used to place needles as well as implants in the lower urinary tract. Generally, 3-D transrectal ultrasound offers new diagnostic and therapeutic possibilities.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Neoplasias da Próstata/diagnóstico por imagem , Ultrassonografia/métodos , Ultrassonografia/tendências , Sistema Urogenital/diagnóstico por imagem , Doenças Urológicas/diagnóstico por imagem , Animais , Meios de Contraste , Humanos , Aumento da Imagem/instrumentação , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/instrumentação , Imageamento Tridimensional/instrumentação , Masculino , Pelve/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Reto/diagnóstico por imagem , Cirurgia Assistida por Computador/métodos , Ultrassonografia/instrumentação , Sistema Urogenital/cirurgia , Doenças Urológicas/cirurgia
14.
Urologe A ; 43(10): 1237-41, 2004 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-15549161

RESUMO

Experimental and clinical studies investigated whether urinary incontinence can be effectively treated with transurethral ultrasound-guided injections of autologous myoblasts and fibroblasts.This new therapy was performed in eight female pigs. It could be shown that the injected cells survived well and that new muscle tissue was formed. Next, 42 patients (29 women, 13 men) suffering from urinary stress incontinence were treated. The fibroblasts were mixed with a small amount of collagen as carrier material and injected into the urethral submucosa to treat atrophies of the mucosa. The myoblasts were directly injected into the rhabdosphincter to reconstruct the muscle and to heal morphological and functional defects. In 35 patients urinary incontinence could be completely cured. In seven patients who had undergone multiple surgical procedures and radiotherapy urinary incontinence improved. No side effects or complications were encountered postoperatively. The experimental as well as the clinical data clearly demonstrate that urinary incontinence can be treated effectively with autologous stem cells. The present data support the conclusion that this new therapeutic concept may represent a very promising treatment modality in the future.


Assuntos
Técnicas de Cultura de Células/métodos , Fibroblastos/transplante , Mioblastos/transplante , Transplante de Células-Tronco/métodos , Engenharia Tecidual/métodos , Incontinência Urinária/diagnóstico , Incontinência Urinária/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Fibroblastos/patologia , Rejeição de Enxerto/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Mioblastos/patologia , Transplante de Células-Tronco/efeitos adversos , Engenharia Tecidual/efeitos adversos , Resultado do Tratamento
15.
Appl Ergon ; 21(1): 7-14, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15676754

RESUMO

Cashier workplaces recently put into service in self-service shops of a retail company provide a face-to-face position of two cashiers. These twin-checkouts involve both traditional goods handling from the front to the rear as well as a reverse technique - i e, forward operation from behind. By means of different methods they have been analysed from an ergonomics point of view and evaluated in respect of operators' workload resulting from the specific layout. The results support the conclusion that the new 'backward' system and twin-checkouts are not inferior to traditional single checkouts. On the contrary, a working technique where the arm moves from behind to the front involves a better approach to accounting for physiological characteristics and obviously allows a better fitting of the task of operators.

16.
Appl Ergon ; 25(6): 346-54, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15676986

RESUMO

Stress and strain during manual tool handling not only depend on factors such as weight to be handled, but are also determined by the design of the man-machine interface. In this study, three different handles of electric hedge-clippers were analysed; the results of a comparative investigation into the physiological cost demanded by the use of the different handles are discussed. Muscular strain was measured via surface electromyography in laboratory experiments with nine male subjects. The results showed significant differences in physiological cost depending on both work height and the handles' shape. Systematic differences in muscular strain between the utilized tools were found, despite the fact that all clippers were compensated with respect to weight and location of the centre of gravity. One of the handle designs enabled working under varying conditions (work height and direction) at a reduced level of muscular strain of the right arm. Results from the physiological evaluation were partly supported by the working persons' own subjective experience. The results of this investigation show that further ergonomic tool and handle design is necessary.

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