Biomedical subjects

Alexander Müller

Publications and source records attributed to Alexander Müller.

9 recordsLinked to original sources

PubMed2006

A developmental dissociation of view-dependent and view-invariant object recognition in adolescence.

Spatial generalization skills in school children aged 8-16 were studied with regard to unfamiliar objects that had been previously learned in a cross-modal priming and learning paradigm. We observed a developmental dissociation with younger children recognizing objects only from previously learnt perspectives whereas older children generalized acquired object knowledge to new viewpoints as well. Haptic and--to a lesser extent--visual priming improved spatial generalization in all but the youngest children. The data supports the idea of dissociable, view-dependent and view-invariant object representations with different developmental trajectories that are subject to modulatory effects of priming. Late-developing areas in the parietal or the prefrontal cortex may account for the retarded onset of view-invariant object recognition.

Adolescent↗

PubMed2006

Disruption of inositol biosynthesis through targeted mutagenesis in Dictyostelium discoideum: generation and characterization of inositol-auxotrophic mutants.

myo-Inositol and its downstream metabolites participate in diverse physiological processes. Nevertheless, considering their variety, it is likely that additional roles are yet to be uncovered. Biosynthesis of myo-inositol takes place via an evolutionarily conserved metabolic pathway and is strictly dependent on inositol-3-phosphate synthase (EC 5.5.1.4). Genetic manipulation of this enzyme will disrupt the cellular inositol supply. Two methods, based on gene deletion and antisense strategy, were used to generate mutants of the cellular slime mould Dictyostelium discoideum. These mutants are inositol-auxotrophic and show phenotypic changes under inositol starvation. One remarkable attribute is their inability to live by phagocytosis of bacteria, which is the exclusive nutrient source in their natural environment. Cultivated on fluid medium, the mutants lose their viability when deprived of inositol for longer than 24 h. Here, we report a study of the alterations in the first 24 h in cellular inositol, inositol phosphate and phosphoinositide concentrations, whereby a rapidly accumulating phosphorylated compound was detected. After its identification as 2,3-BPG (2,3-bisphosphoglycerate), evidence could be found that the internal disturbances of inositol homoeostasis trigger the accumulation. In a first attempt to characterize this as a physiologically relevant response, the efficient in vitro inhibition of a D. discoideum inositol-polyphosphate 5-phosphatase (EC 3.1.3.56) by 2,3-BPG is presented.

2,3-Diphosphoglycerate↗

PubMed2006

Sexual dysfunction in the patient with prostatitis.

Prostatitis (chronic prostatitis/chronic pelvic pain syndrome ) is a common condition in men that accounts for a significant number of visits to a medical doctor or urologist. It is one of the most widely diagnosed conditions in men who attend urologic clinics. Erectile dysfunction, defined as the consistent inability to obtain and/or maintain a penile erection sufficient for adequate sexual relations, also is a common problem. This review explores the links between sexual dysfunction and prostatitis. Most of the data linking lower urinary tract symptoms and erectile dysfunction suggest that lower urinary tract symptoms impair the overall quality of life and that a low quality of life contributes to or causes erectile dysfunction. Prostatitis-like symptoms such as perineal, penile, and suprapubic discomfort or pain during or after ejaculation and voiding complaints such as irritative and obstructive voiding symptoms (urinary frequency, urgency, and dysuria) may affect the global emotional well-being of a man. Erectile dysfunction also is strongly associated with a negative impact on the quality of life. The available literature demonstrating the influence of CP/CPPS on the incidence of erectile dysfunction is scant. From the literature, it is known that lower urinary tract symptoms and benign prostatic hyperplasia are definitely related to erectile dysfunction. Any kind of pain is likely to be the most significant symptom in men with CP/CPPS as it relates to sexual dysfunction. Sexual dysfunction such as ejaculation discomfort is described as a symptom of CP/CPPS. Most of the data linking the two suggest that CP/CPPS impairs the overall quality of life and it is this that contributes to or causes erectile dysfunction.

Back Pain↗

PubMed2006

Cardiovascular disease, metabolic syndrome and erectile dysfunction.

PURPOSE OF REVIEW: Erectile dysfunction and cardiovascular disease share the same risk factors such as hypertension, diabetes, dyslipidemia, obesity, and smoking, all of which are implicated in causing endothelial dysfunction. In this review, an overview is given on the role of endothelium in the pathophysiology of erectile dysfunction, cardiovascular disease, and the metabolic syndrome as well as the links between them. RECENT FINDINGS: Current literature offers strong evidence that endothelial dysfunction and erectile dysfunction are linked. Erectile dysfunction appears to be one of the earliest signs of systemic vascular disease and might be considered as an early marker for subclinical cardiovascular disease. Obesity is one of the many risk factors for cardiovascular disease and is also associated with hypertension, dyslipidemia, glucose intolerance, and insulin resistance, which together define the metabolic syndrome. Experimental, clinical, and epidemiologic studies support the association between metabolic syndrome and cardiovascular disease. SUMMARY: The above-mentioned risk factors are a potential threat to the penile endothelium and the smooth muscle tissue leading to functional and structural changes. These important pathophysiologic factors are the foundation for the strong link between erectile dysfunction and cardiovascular disease. Recent literature supports the link between metabolic syndrome and erectile dysfunction and highlights metabolic syndrome as a potential risk factor for the development of erectile dysfunction.

Cardiovascular Diseases↗

PubMed2005

Photoselective vaporization (PVP) versus transurethral resection of the prostate (TURP): a prospective bi-centre study of perioperative morbidity and early functional outcome.

OBJECTIVES: To compare the early follow-up and perioperative morbidity of photoselective vaporization (PVP) and transurethral resection of the prostate (TURP) in patients (pts.) suffering from lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH). MATERIAL AND METHOD: 101 pts. underwent PVP (n = 64) and TURP (n = 37) in a prospective, non-randomized bi-centre trial. Inclusion criteria were identical at both centres. Primary outcome parameters were maximum urinary flow rate (Q(max)), post-void residual volume (V(res)), International Prostate Symptom Score (IPSS). Secondary outcomes included intraoperative surgical parameters and perioperative and post-discharge morbidity. RESULTS: Baseline characteristics of both groups were similar. Operating time was slightly shorter in the TURP group (p = 0.047). During TURP significant more irrigation solution was used (p < 0.001). Decrease of serum haemoglobin (p = 0.027) and serum sodium (p = 0.013) was larger after TURP. Catheter drainage was removed significant earlier after PVP than after TURP (p < 0.001). Outcome of Q(max), and IPSS were similar in both groups within 6 months. The sort of perioperative complications was different in both groups, however overall cumulative perioperative morbidity was comparable (PVP 39.1% versus TURP 43.2.1%; ns). CONCLUSION: PVP provides excellent intraoperative safety, instant tissue removal, and immediate relief from obstructive voiding symptoms, similar to TURP. Early outcomes 6-months after PVP and TURP are comparable.

Aged↗

PubMed2005

Photoselective vaporization of the prostate: the basel experience after 108 procedures.

OBJECTIVES: This study aims to investigate safety and efficacy of 80 watt high-power potassium titanyl phosphate (KTP) laser vaporization of the prostate in men with lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH). METHODS: 108 patients underwent 80W KTP laser vaporization. Functional follow-up included measurement of maximum urinary flow rate (Qmax), postvoid residual volume (Vres) and International Prostate Symptom Score (IPSS) within a 12 months period. RESULTS: The average prostate volume was 52.2+/-24.3 ml and the preoperative PSA value was 3.6+/-3.6 ng/dl. Mean operation time was 54.5+/-25.0 min. Qmax increased highly significantly (p<0.001) by 111% (+7.9 ml/s) at discharge, 212% (+15.1 ml/s) after three months, 201% (+14.3 ml/s) after six months and 252% (+17.9 ml/s) after 12 months. Correspondingly, Vres, IPSS and Bother Score improved to an extent that was statistically highly significant (p<0.001) immediately after surgery. The observed complication rate within one year was low. CONCLUSIONS: 80 W KTP laser vaporization is a virtually bloodless, safe and effective procedure for surgical treatment of LUTS secondary to BPH. A significant improvement of objective and subjective voiding parameters was observed just after surgery. KTP laser vaporization is associated with a low rate of complications.

Aged↗

PubMed2005

Sexual dysfunction in the patient with prostatitis.

PURPOSE OF REVIEW: Prostatitis [chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS)] is a common condition in men that accounts for a significant number of visits to a medical doctor or urologist. It is one of the most widely diagnosed conditions in men attending urologic clinics. Erectile dysfunction, defined as the consistent inability to obtain and/or maintain a penile erection sufficient for adequate sexual relations, is also a common problem. This review explores the links between sexual dysfunction and prostatitis. RECENT FINDINGS: Most of the data linking lower urinary tract symptoms and erectile dysfunction suggest that lower urinary tract symptoms impair the overall quality of life and that a low quality of life contributes to or causes erectile dysfunction. Prostatitis-like symptoms such as perineal, penile, and suprapubic discomfort or pain during or after ejaculation and voiding complaints such as irritative and obstructive voiding symptoms: urinary frequency, urgency, and dysuria may affect the global emotional well-being of a man. Erectile dysfunction is also strongly associated with a negative impact on the quality of life. SUMMARY: The available literature demonstrating the influence of CP/CPPS on the incidence of erectile dysfunction is scant. From the literature, it is known that lower urinary tract symptoms and benign prostatic hyperplasia are definitely related to erectile dysfunction. Any kind of pain is likely to be the most significant symptom in men with CP/CPPS as it relates to sexual dysfunction. Sexual dysfunction like ejaculation discomfort is described as a symptom of CP/CPPS. Indeed, most of the data linking the two suggest that CP/CPPS impairs the overall quality of life and it is this that contributes to or causes erectile dysfunction.

Adult↗

PubMed2004

Development of configural 3D object recognition.

There is evidence for the late development in humans of configural face and animal recognition. We show that the recognition of artificial three-dimensional (3D) objects from part configurations develops similarly late. We also demonstrate that the cross-modal integration of object information reinforces the development of configural recognition more than the intra-modal integration does. Multimodal object representations in the brain may therefore play a role in configural object recognition.

Adolescent↗

PubMed2003

Sub-10-fs, terawatt-scale Ti:sapphire laser system.

A three-stage, 1-kHz amplifier system delivering pulses shorter than 10 fs with a peak power in excess of 0.3 TW is reported. Passive and active spectral intensity and phase control allows the preservation of a bandwidth of 120 nm (FWHM) to as high as multimillijoule energy levels and temporal compression of the broadband pulses close to their Fourier limit. The system is scalable to peak powers well beyond 1 TW and holds promise for substantially advancing the state of the art of coherent laboratory soft-x-ray sources.

Journal Article↗