Biomedical subjects

F Müller

Publications and source records attributed to F Müller.

At least 19 recordsLinked to original sources

PubMed2006

[Operative treatment of proximal humeral fractures with helix wire].

BACKGROUND: Between 1 January 2000 and 31 December 2002, a total of 50 patients with a dislocated or unstable fracture of the proximal humerus were treated surgically with a titanium helix wire introduced retrogradely into the medullary cavity. MATERIAL AND METHODS: Fracture classification showed 8 cases of a two-fragment fracture, 32 cases of a three-fragment fracture, and 10 cases of a so-called four-fragment fracture. A retrospective radiographic and medical review of all 50 patients showed postoperative complications in 24% of the cases; in 8 cases (16%) secondary loss of retention occurred with consecutive projection of the helix wires into the subacromial joint space. There were two cases each (4%) of perforation of the helix wire into the joint space without loss of retention and fracture dehiscence because of a blocking mechanism by the helix wire in the subcapital fracture gap. The postoperative revision rate was 18% (9/50) as a result. Of 50 patients with a titanium helix wire, 38 (76%) were reviewed after an average of 23 months (12-31). Radiologically partial necrosis of the head of the humerus was seen in two patients and there was necrosis of the head of the humerus with pseudarthrosis in one patient, which had a negative effect on the Constant score. RESULTS: Because of a change of procedure (n=5) and intercurrent deaths (n=5) only 2 of 12 patients, in whom complications had occurred postoperatively, could be followed up clinically; the results of the follow-up are sure to be distorted by this selection effect. Of 38 patients, 32 (84%) showed very good to good results functionally; the average Constant score was 74 points and the average age- and sex-specific corrected score was 92%. DISCUSSION: Thus, the procedure does not achieve better functional results compared to other rigid and semirigid internal fixation methods while it has a high complication and revision rate compared to other rigid and semirigid internal fixation methods. Moreover, early functional treatment is not possible so that the titanium helix wire represents a retention aid rather than stable internal fixation. Overall we cannot recommend the procedure for the operative management of proximal humerus fractures further and have abandoned it ourselves.

Adult↗

PubMed2006

Prospective, randomized controlled trial on Lactobacillus rhamnosus in infants with moderate to severe atopic dermatitis.

BACKGROUND: A reduction of symptoms of atopic dermatitis (AD) in small infants by the administration of Lactobacillus rhamnosus has been reported in a few studies. One study with older children and adolescents failed to show any effect. OBJECTIVES: We conducted a prospective study to reassess the efficacy of orally administered L. rhamnosus strain GG (LGG) in infants with AD. METHODS: In a randomized, double-blind, placebo-controlled study, 54 infants aged 1-55 months with moderate to severe AD were randomized to daily 10 x 10(9) colony-forming units of LGG or to placebo during an 8-week intervention phase. Emollients, class I-II topical corticosteroids and antihistamines were permitted. RESULTS: The treatment with LGG was well tolerated. At the end of treatment there were no significant differences between the groups with respect to clinical symptoms (SCORAD, pruritus, sleep loss), the use of topical corticosteroids and antihistamines, immunological parameters, or health-related quality of life of the parents. CONCLUSIONS: Our results could not confirm LGG as an effective treatment of AD in infancy.

Child, Preschool↗

PubMed2006

Polyclonal expansion of large granular lymphocytes in common variable immunodeficiency - association with neutropenia.

Common variable immunodeficiency (CVID) is the most frequent symptomatic primary immunodeficiency disease, characterized by low levels of circulating immunoglobulins and recurrent bacterial infections, particularly of the respiratory tract. T cell dysfunction is often present, and lymphoproliferative and autoimmune disorders as well as haematological cytopenias are frequently observed. In this study, we report a polyclonal expansion of large granular lymphocytes (LGL) in a substantial proportion of CVID patients, associated with splenomegaly, increased numbers of CD8(+) T cells, inverted CD4 : CD8 T cell ratios and neutropenia. CVID patients who had both increased numbers of LGL and granulocytopenia had elevated levels of soluble Fas ligand (sFasL). Our observations indicate that CVID may be added to the list of inflammatory diseases associated with increased numbers of LGL. Furthermore, our findings suggest common pathogenic mechanisms of granulocytopenia in CVID and lymphoproliferative disease of granular lymphocytes.

Adult↗

PubMed2005

Thrombolysis in stroke patients aged 80 years and older: Swiss survey of IV thrombolysis.

This databank-based, multicenter study compared all stroke patients with IV tissue plasminogen activator aged > or = 80 years (n = 38) and those < 80 years old (n = 287). Three-month mortality was higher in older patients. Favorable outcome (modified Rankin scale < or = 1) and intracranial hemorrhage (asymptomatic/symptomatic/fatal) were similarly frequent in both groups. Logistic regression showed that stroke severity, time to thrombolysis, glucose level, and history of coronary heart disease independently predicted outcome, whereas age did not.

Age Factors↗

PubMed2005

[High speed glottographic diagnostics in laryngology].

INTRODUCTION: High speed imaging (HSI) allows thousands of pictures to be taken of the vibrating vocal folds per second. Although already developed in 1939 in the USA, this method only became clinically useful a few years ago as the amount of data exceeded the capacity of physical memory. MATERIALS AND METHODS: Rigid endoscopes are normally used for high speed glottography. After clinical investigation of the patient, kymographic analysis can be carried out off-line. Up to 8,000 grayscale images of 256 x 256 pixels can be stored by the Wolf HS Endocam 5560 that we used in our study. A maximum of 4,000 images/s can be taken by the high speed camera. RESULTS: In high speed glottography, analysis and documentation of single vocal fold movements within the vibratory cycle is possible. In contrast to stroboscopic investigations, aperiodic movements of the vocal folds can be visualized. The duration of a recording differs from 2 to 4 s depending on the capture speed. The data transfer to the computer for archiving and analysing the images takes a few minutes. CONCLUSION: HSI has advantages and disadvantages compared to videoendoscopy and videostroboscopy. The main advantage is the visualisation of aperiodic movements, the disadvantages are the transfer time for the data and the poorer image quality compared to conventional videoendoscopy. Nevertheless HSI is a very promising technique in laryngological investigation.

Endoscopy↗

PubMed2005

[Oral health, dental state and nutrition in older adults].

The loss of natural teeth impairs essentially the chewing function and can only partly be restored by the insertion of dental prostheses. Equally, xerostomia and dysphagia may aggravate the nutritional intake in older adults. Often denture wearers do subjectively not notice the adjustment of their food choice and the employment of special preparation techniques. Finally the dental state influences the nutritional intake. A reduced number of teeth correlates with the intake of less calories, proteins, fat, non-starch polysaccharides and vitamins. Often missing calories are compensated by an increased consumption of sugar and fat. Especially edentulous persons with a low level of education choose a diet which is rich in fat and sugar. Further the daily intake of fruit and vegetables diminishes along with fewer occlusal contacts in posterior teeth. The restoration of the chewing function by dental intervention does not lead to an improvement of the nutritional intake by itself and should therefore always be complemented by nutritional advice.

Aged↗

PubMed2005

Oxidative stress related markers in the "VITA" and the centenarian projects.

Oxidative stress seems to play an important role in the pathophysiology of Alzheimer's disease (AD). At present there are no easily accessible biochemical markers for AD. We performed activity assays for platelet MAO-B and erythrocyte Cu/Zn-SOD as well as Western blotting for these two proteins. Moreover, we assessed plasma lactoferrin and performed RFLP-analysis for the MAO-B-intron-13-polymorphism in patients from the Vienna-Transdanube Aging (VITA) and from the so called centenarian project. The first one, VITA, is a community-based cohort study of all 75 years old inhabitants of a geographical region of Vienna. The centenarian project investigates chronic care in-old patients suffering from AD. In both sexes platelet MAO-B activity increased significantly in the AD group, and Cu/Zn-SOD activity decreased, but the latter effect was significant only in females. No significant difference was found regarding plasma lactoferrin. No correlation was found between MAO-Bi13 and MAO-B platelet activity or allele MAO-Bi13 and disease frequency. These results point to the possibility that a combination of MAO-B and SOD activity levels might be useful tools for an early diagnosis of AD.

Aged↗

PubMed2005

Modulatory effect of mannose-binding lectin on cytokine responses: possible roles in HIV infection.

BACKGROUND: Mannose-binding lectin (MBL) is a soluble receptor of the innate immune system, probably contributing to antimicrobial defence. The possible role of MBL in HIV infection is unclear. MATERIALS AND METHODS: Peripheral blood mononuclear cells (PBMCs) from 28 HIV-infected patients and 13 healthy controls were stimulated with MBL and costimulated with HIV-1 gp120 or mannan from Saccharomyces cerevisiae before inflammatory responses in PBMC cultures were examined by enzyme-linked immunosorbent assay (ELISA) and flow cytometry. HIV-1 RNA replication in vitro was assessed by quantitative reverse transcription polymerase chain reaction (RT-PCR) in supernatants from patients with measurable HIV-1 RNA levels. RESULTS: (i) Enhanced TNF-alpha responses were observed when PBMCs from healthy controls and HIV-infected patients were stimulated with MBL and costimulated with HIV-1 gp120 or mannan. (ii) MBL stimulation induced increased HIV RNA replication in culture supernatants when costimulated with mannan. CONCLUSIONS: The present study suggests a modulatory role of MBL on cytokine responses, and HIV replication after stimulation with microbial products. These effects of MBL on inflammatory responses and viral replication may be clinically relevant for HIV infection.

Adult↗

PubMed2005

Characterization of the force effect of aqueous and oily eye drops.

During the instillation of eye drops the drop impact affects a mechanical irritation on the eye surface. The force impact occurring in the moment of impact may be measured in vitro. Four commercially available eye drop preparations of different consistency and viscosity were tested. In dependance on the drip distance, the quantity of force impact was determined as well as the maximally effecting force during impact in each case. Whereas the force impact increased with all preparations with rising drip distance, only the higher viscosity solutions showed an approximate linear increase of the maximal force. With the aqueous low-viscosity eye drops, peak forces were ascertained. The drop oscillation was considered as the cause. The test results show that the consistency of eye drop preparations and their resulting physical-chemical properties like viscosity influence the quantity of the maximal force during the drop impact.

Algorithms↗

PubMed2005

Comparative in vitro investigation of the forces exerted by eye drops and eye spray.

Topical administration of ophthalmic drugs is predominantly carried out in the form of eye drops. The application of an eye spray represents a feasible alternative to drop instillation with regard to the clinical efficacy. In this study the forces exerted during the application of eye drops and eye spray to a surface were measured in vitro and compared with each other. Whereas the maximal forces that occurred with a falling drop tended to increase with greater application distance, the forces decreased with spraying. From an application distance of 3 cm the eye spray proved to have a more favorable mechanical force effect than the eye drops. In view of the loss of experimental liquid caused by spray application as well as the diameter of the spray cone, a spray distance of from 4 cm to 5 cm can be deemed to be optimal.

Administration, Topical↗

PubMed2004

Highly directional emission from photonic crystal waveguides of subwavelength width.

Recently it has been shown that it is possible to achieve directional emission out of a subwavelength aperture in a periodically corrugated metallic thin film. We report on theoretical and experimental studies of a related phenomenon concerning light emitted from photonic crystal waveguides that are less than a wavelength wide. We find that the termination of the photonic crystal end facets and an appropriate choice of the wavelength are instrumental in achieving very low numerical apertures. Our results hold promise for the combination of photonic crystal waveguides with conventional optical systems such as fibers, waveguides, and freely propagating light beams.

Journal Article↗

PubMed2004

TOR action in mammalian cells and in Caenorhabditis elegans.

The p70 S6 kinase (p70 S6K) was the first signaling element in mammalian cells shown to be inhibited by rapamycin. The activity of the p70 S6K in mammalian cell is upregulated by extracellular amino acids (especially leucine) and by signals from receptor tyrosine kinases (RTKs), primarily through activation of the type 1A PI-3 kinase. The amino acid-/rapamycin-sensitive input and the PI-3 kinase input are co-dominant but largely independent, in that deletion of the amino-terminal and carboxy-terminal noncatalytic sequences flanking the p70 S6K catalytic domain renders the kinase insensitive to inhibition by both rapamycin and by withdrawal of amino acids, whereas this p70 S6K mutant remains responsive to activation by RTKs and to inhibition by wortmannin. At a molecular level, this dual control of p70 S6K activity is attributable to phosphorylation of the two p70 S6K sites: The Ptd Ins 3,4,5P3-dependent kinasel (PDK1) phosphorylates p70 S6K at a Thr on the activation loop, whereas mTOR phosphorylates a Thr located in a hydrophobic motif carboxyterminal to the catalytic domain. Together these two phosphorylations engender a strong, positively cooperative activation of p70 S6K, so that each is indispensable for physiologic regulation. Like RTKs, the p70 S6K appears early in metazoan evolution and comes to represent an important site at which the more ancient, nutrient-responsive TOR pathway converges with the RTK/PI-3 kinase pathway in the control of cell growth. Dual regulation of p70 S6K is seen in Drosophila; however, this convergence is not yet evident in Caenorhabditis elegans, wherein nutrient activation of the insulin receptor (InsR) pathway negatively regulates dauer development and longevity, whereas the TOR pathway regulates overall mRNA translation through effectors distinct from p70 S6K, as in yeast. The C. elegans TOR and InsR pathways show none of the cross- or convergent regulation seen in mammalian cells. The nature of the elements that couple nutrient sufficiency to TOR activity remain to be discovered, and the mechanisms by which RTKs influence TOR activity in mammalian cells require further study. One pathway for RTK control involves the tuberous sclerosis complex, which is absent in C. elegans, but of major importance in Drosophila and higher metazoans.

Animals↗

PubMed2004

[Influence of the head position in laryngoscopy].

INTRODUCTION: The aim of this study was to determine the optimal position of the head during larygoscopy. MATERIAL AND METHODS: During fiberoptic evaluation of the larynx, the head position of eight subjects (5 male, 3 female) was changed systematically. The influence of reclining and anteversion, tilting and rotation of the head on the quality of the endoscopic images was determined. RESULTS: The vocal tract became wider and the view onto the glottis could be improved by reclining the head and anteversion of the chin. On rotation of the head, the hypopharynx of the same side became narrower. This is well known and is used worldwide in the therapy of dysphagia. DISCUSSION: Positioning of the patient is important in laryngoscopy. Reclining the head and forward inclination of the trunk (horizontal axis of the mouth) seems to be the best position for obtaining an optimal view onto the glottis.

Adult↗

PubMed2004

Functional impression and jaw registration: a single session procedure for the construction of complete dentures.

The conventional fabrication of complete dentures involves two separate clinical sessions for functional impression making and jaw registration. The presented method combines both procedures in one session. The aim of this study was to survey the three-dimensional tooth positions in complete dentures with reference to the ridges to establish arbitrary guideline values that could be used for the manufacturing of tooth-position analogue plastic rims on functional impression trays. New complete dentures were fabricated by supervised undergraduate students in the conventional manner for 104 edentulous patients. The position of the maxillary teeth was surveyed in the horizontal plane using the Schmuth 'vizor-measuring plate'. The vertical dimension of occlusion, represented as the distance between opposing ridge areas of the dentures in maximum intercuspation, was measured at different sites by means of a Gutowski gauge. The tooth positions on the dentures varied widely, e.g. the horizontal distances between the incisive papilla and the maxillary incisors was 7.1 +/- 2.3 (3-14) mm. The vertical dimension of occlusion, which is most important in the jaw registration, varied equally with an anterior inter-alveolar distance between 12 and 33 (20.4 +/- 4.0) mm. Arbitrary moulding of the tooth position-analogue plastic rims does not seems to be an ideal method of pre-shaping functional impression trays, because the individual anatomical variation is considerable. Alternatively, the horizontal and vertical tooth positions of functionally and aesthetically pleasing dentures should be measured to pre-shape the rims of functional impression trays in the maxillary and the mandibular jaw. Such trays are a valuable tool for functional impressions and an immediate preliminary jaw registration in the fabrication of new complete dentures. This method allows a first try-in of the full set-up in the third clinical visit without loosing precision.

Adult↗

PubMed2004

The primitive streak, the caudal eminence and related structures in staged human embryos.

The caudal region of the trunk was reassessed in 52 serially sectioned human embryos of stages 8-23, 42 of which were controlled by precise graphic reconstructions. The following observations, new for the human, are presented. (1) The neurenteric canal is an important landmark because rostral to it the neural plate of stages 8, 9, and the main part of the notochord develop, whereas caudal to it the neural plate of stages 10-12 and the caudal portion of the notochord are formed. All somites at stages 9-11 and probably also at stage 12 arise rostral to the site of the neurenteric canal. (2) A 'chordoneural hinge' can be detected in stages 10 and 11, where the caudal part of the neural plate gives off cells that probably participate in the production of mesenchyme. (3) When apparent disappearance of the epiblast is used as a criterion, then the primitive streak seems to end during stage 9. (4) The caudal eminence, derived from the primitive streak and covered by ectoderm, forms at stage 10 caudal to the site of the former neurenteric canal and persists as a terminal cap to at least stage 14, although formation of mesenchyme continues in stages 15 to 17 or 18. (5) As the region rostral to the site of the neurenteric canal grows because of the development of somites, the caudal eminence is shifted caudally. (6) The caudal eminence is most active developmentally during stage 13, when most of the required (ca 6 out of 9) pairs of somites appear. (7) The eminence produces the caudal part of the notochord and, after closure of the caudal neuropore, all caudal structures, but it does not produce even a temporary 'tail' in the human. (8) A temporal overlap results between primary and secondary development in the caudal part of the notochord. (9) Primary development begins very early with the formation of the inner cell mass at stage 3, and includes the development of the somites rostral to the neurenteric canal, whereas secondary development, with the exception of the notochord caudally, commences at stage 12. (10) Primary neurulation lasts from stage 8 to stage 12, secondary from stage 12 to stages 17 or 18. (11) Secondary development and secondary neurulation are characterized morphologically by direct formation of structures (notochord, postcloacal gut, neural cord/neural tube) from mesenchyme.

Ectoderm↗

PubMed2004

Olfactory structures in staged human embryos.

The olfactory region was investigated in 303 serially sectioned human embryos, 23 of which were controlled by precise graphic reconstructions. The following findings in the embryonic period are new for the human. (1) The nasal plates arise at the neurosomatic junction, as do also the otic placodes. (2) Crest comes from the nasal plates later (stage 13) than the maximum production in the neural folds (stage 10). (3) The crest arises and migrates during a much longer time (at least until the end of the embryonic period) than the neural crest of the head, where origin and migration end at stage 12. (4) Olfactory nerve fibres enter the brain at stage 17, the vomeronasal fibres and those of the nervus terminalis at stages 17 and 18. (5) Fibre connections between the olfactory tubercle and the olfactory bulb, as well as those to the amygdaloid nuclei, forebrain septum, and hippocampus, develop during and after stage 17. (6) Mitral cells appear late in the embryonic period. (7) Localized, although incomplete, lamination of the olfactory bulb is detectable at the embryonic/fetal transition. (8) Tangential migratory streams of neurons, from stage 22 to the early fetal period, proceed from the subventricular zone of the olfactory bulb towards the future claustrum; they remain within the insular region but are separated from the cortical plate. (9) In future cebocephaly morphological indications may be visible as early as stage 13. The various findings are integrated by means of staging, and current information for the fetal period is tabulated from the literature.

Embryonic Development↗

PubMed2003

Cytomegalovirus infection induces production of human interleukin-10 in macrophages.

Earlier findings have suggested that the balance between interleukin-10 and tumor necrosis factor alpha levels in serum may influence the outcome of cytomegalovirus infection in renal transplant recipients. Therefore, the aim of the present study was to investigate whether human cytomegalovirus induces interleukin-10 production in macrophages. Experiments using human cytomegalovirus (strain 2006), ultraviolet-inactivated cytomegalovirus, and mock-infected differentiated THP-1 cells with or without ganciclovir or monoclonal anti-tumor necrosis factor alpha antibodies were performed. Cytomegalovirus-infected cells produced significantly higher levels of human interleukin-10 mRNA and interleukin-10 than ultraviolet-inactivated cytomegalovirus or mock-infected cells. The addition of ganciclovir had little effect on interleukin-10 production. Anti-tumor necrosis factor alpha antibodies appeared to reduce the interleukin-10 levels. In conclusion, human cytomegalovirus infection of macrophages induces production of human interleukin-10. This requires viral entry, but not full viral replication.

Biomarkers↗

PubMed2003

The functional effect of adenoviral Na+/Ca2+ exchanger overexpression in rabbit myocytes depends on the activity of the Na+/K+-ATPase.

OBJECTIVES: The functional consequences of Na+/Ca2+ exchanger (NCX) overexpression in heart failure have been controversially discussed. NCX function strongly depends on intracellular sodium which has been shown to be increased in heart failure. METHODS AND RESULTS: We investigated the Na+/K+-ATPase (NKA) inhibitor ouabain (0.5-16 micromol/l) in electrically stimulated, isotonically contracting adult rabbit cardiocytes overexpressing NCX after adenoviral gene transfer (Ad-NCX-GFP, 48 h culture time). Myocytes transfected with adenovirus encoding for green fluorescent protein (Ad-GFP) served as a control. Contractions were analyzed by video-edge detection. In the Ad-NCX-GFP group, the maximum inotropic response was significantly reduced by 50.7% (P<0.05). This was a result of an enhanced susceptibility to contracture after exposure to the drug (median concentration (25-75%): 4 (4-8) vs. 8 (6-16) micromol/l, P<0.05). When analyzing relaxation before contracture, the maximum relaxation velocity was reduced (0.15+/-0.04 vs. 0.27+/-0.04 microm/s, P<0.05) and the time from peak shortening to 90% of relaxation was increased (298+/-39 vs. 185+/-15 ms, P<0.05). No differences in systolic and diastolic parameters were observed with the Na+ channel modulator BDF9198 (1 micromol/l). CONCLUSIONS: Inhibition of NKA by ouabain induces a combined diastolic and systolic dysfunction in NCX overexpressing rabbit myocytes. This may be the consequence of cytoplasmic Ca2+ overload due to inhibition of forward mode or induction of reverse mode Na+/Ca2+ exchange. In end-stage failing human myocardium and during digitalis treatment this mechanism may be of major importance.

Adenoviridae↗