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M Hinz

Publications and source records attributed to M Hinz.

At least 19 recordsLinked to original sources
PubMed2006

Vertical distraction of fibula transplant in a case of mandibular defect caused by shotgun injury.

This case demonstrates the successful aesthetic and functional reconstruction of a complex facial gun-shot injury with extended bone defects and soft tissue destructions using a 3-step procedure. Initially, a reconstruction plate was inserted, later a fibula transplant enabled the basic reconstruction and finally was distructed in a 3rd session. The rationale behind the sequencing of surgical sessions was the extended bony defect and soft-tissue destruction. The main problem in this type of wound is hypoxia or anoxia of the receptor bed for the transplant. A microvascular anastomosized bone transplant is necessary for sufficient oxygen tension in the recipient site. The anatomical dimensional disproportion of the transplanted free fibula graft and the shape of the mandible were corrected prior to the insertion of dental implants by means of vertical distraction.

Bone Plates↗
PubMed2006

Sleep disordered breathing in the elderly: a three year longitudinal cohort study.

The objective of this investigation was to assess the association between the presence of sleep disordered breathing (SDB) and daytime sleepiness, body mass index, hospitalisation, and survival. To this end, a prospective longitudinal study was conducted in the elderly population consisting of 80 patients of either sex over the age of 65 years admitted to a city hospital in Germany without any history of SDB. All patients met the following exclusion criteria: age <65 yr, heart failure, and chronic obstructive lung disease. Baseline anthropometric and cardiorespiratory (one-night portable polygraphic recording) data, and a standardized sleep and sleepiness-questionnaires (Epworth Sleepiness Scale, ESS) were obtained in 1999. A second screening was conducted in 2003. Thirty one women and 34 men completed the follow-up after 3 years. These patients were divided into two subgroups: (i) no clinically relevant SDB and (ii) SDB (apnea-hypopnea index, AHI, >or=5 plus excessive day time sleepiness, ESS, >9). Six men and 3 women fulfilled the criteria of SDB. Thirty three percent of patients with SDB and 20% of patients without SDB died during the follow-up period. Duration of hospital stay was 35 days for the SDB patients and 20 days for patients without it. Body weight and sleepiness did not change significant over the 3-year period between the two cohorts. We conclude that the presence of SDB was associated with a 1.5-fold higher mortality and longer hospital stay in elderly patients over a period of 3 years even in persons without previous history of SDB. Daytime sleepiness was a better predictor than AHI or BMI for death.

Aged↗
PubMed2005

Sleep disordered breathing in the elderly: comparison of women and men.

The prevalence of obstructive sleep apnea syndrome in patients up to the age of 60 is known to be two times higher in men then in women. Hormonal changes during menopause might underlie changes in this relationship in the elderly. This study was designed to detect differences in the type and frequency of sleep-disordered breathing between women and men over the age of 65 years, having the same body mass index. The study was conducted using a matched-pair approach consisting of a sample population of 40 pairs of patients over the age of 65. All patients met the following exclusion criteria: age below 65, heart failure, chronic obstructive lung disease. Polygraphy was conducted by means of a portable recorder. All measured indices were higher in men than in women. The apnea index was 2.8 +/-4.1 in men and 0.6 +/-1.4 in women. The apnea/hypopnea index was 10.2 +/-11.4 and 4.8 +/-3.9, respectively. These differences were significant (P<0.05). Significant differences also were observed when central (men 8.1 +/-13.1, women 3.1 +/-8.2), mixed (men 5.1 +/-11.4, women 0.4 +/-1.3), and obstructive (women men 8.6 +/-20.1, 1.0 +/-4.3) apnea indices were compared. In conclusion, the study demonstrates that elderly patients showed gender-dependent differences in the type and frequency of sleep-related breathing disorders. Men suffered from all kinds of apnea more frequently than women.

Aged↗
PubMed2004

Promoter-induced reactive phase separation in surface reactions.

Promoters are adsorbed mobile species which do not directly participate in a catalytic surface reaction, but can influence its rate. Often, they are characterized by strong attractive interactions with one of the reactants. We show that these conditions lead to a Turing instability of the uniform state and to the formation of reaction-induced periodic concentration patterns. Experimentally such patterns are observed in catalytic water formation on a Rh(110) surface in the presence of coadsorbed potassium.

Journal Article↗
PubMed2004

[Tear outflow. Impact of mucins and TFF-peptides].

The epithelial lining of the lacrimal sac and the nasolacrimal duct consists of pseudo-stratified, columnar epithelia rich in goblet cells. Major secretory products of the epithelial cells are mucins together with TFF peptides. Expression and distribution of several mucins and TFF peptides in the human efferent tear ducts was investigated by means of reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. mRNAs for all the mucins investigated, MUC1, MUC2, MUC4, MUC5AC, MUC5B and MUC7, were detected in healthy human lacrimal sacs and nasolacrimal ducts. Both MUC5AC and MUC5B were detected in goblet cells forming intraepithelial mucous glands. MUC7 together with TFF3 occurred only in columnar epithelial cells of the efferent tear duct system. The mucin diversity of the efferent tear ducts could enhance tear transport and antimicrobial defense. The absence of some mucins in non-functioning although patent segments of the lacrimal passage, suggests that mucins ease tear flow through the efferent tear ducts because these conditions are associated with epiphora. Disorders in the balance of single mucins could be of importance with regard to dacryostenosis, dacryocystitis and dacryolith formation.

Biological Transport, Active↗
PubMed2004

Distribution of TFF peptides in corneal disease and pterygium.

The central cornea of 10 cadavers and 33 patients suffering from keratoconus, herpetic keratitis, Fuchs' dystrophy and pterygium were analysed focusing on the expression of TFF peptides by means of reverse transcription polymerase chain reaction and immunohistochemistry. TFF1 and TFF3 transcripts were detected in healthy corneae as well as in pterygia. Only TFF3 mRNA was transcribed in keratoconus, Fuchs' dystrophy and herpetic keratitis. Immunohistochemistry revealed absence of all three TFF peptides in healthy corneae but production of TFF3 in each of the diseased corneae. In pterygia both TFF1 and TFF3 synthesis was detectable in goblet cells. The absence of TFF peptide production in the healthy cornea indicates that TFF3 secretion is induced in different corneal diseases by yet unknown stimuli. Here TFF3 synthesis can be interpreted as a protection mechanism, because all corneal diseases analysed are characterized by progressive tissue destruction. TFF1 and TFF3 production by goblet cells in pterygia is comparable to the healthy conjunctiva suggesting that TFF peptides do not play a significant role in the pathogenesis of pterygia.

Cornea↗
PubMed2003

Arrays of immobilized oligonucleotides--contributions to nucleic acids technology.

The interactions of nucleic acids technology and the technology of arrayed nucleic acids are described, showing the interdependence of nucleic acids chemistry, surface chemistry, (micro-) technology and the requirements of bio-medical applications. The methods and problems of the production of large numbers of oligonucleotides as well as the methods of arraying oligonucleotides are highlighted. The basic approaches, in-situ synthesis and postsynthetic immobilization, are described with a special emphasis on the postsynthetic immobilization of ready-made oligonucleotides on support materials. Techniques for the detection of nucleic acids interactions on arrays are outlined in brief.

Adsorption↗
PubMed2001

Constitutive NF-kappaB maintains high expression of a characteristic gene network, including CD40, CD86, and a set of antiapoptotic genes in Hodgkin/Reed-Sternberg cells.

Constitutively activated nuclear factor (NF)-kappaB is observed in a variety of neoplastic diseases and is a hallmark of the malignant Hodgkin and Reed-Sternberg cells (H/RS) in Hodgkin lymphoma. Given the distinctive role of constitutive NF-kappaB for H/RS cell viability, NF-kappaB-dependent target genes were searched for by using adenoviral expression of the super-repressor IkappaBDeltaN. A surprisingly small but characteristic set of genes, including the cell-cycle regulatory protein cyclin D2, the antiapoptotic proteins Bfl-1/A1, c-IAP2, TRAF1, and Bcl-x(L), and the cell surface receptors CD86 and CD40 were identified. Thus, constitutive NF-kappaB activity maintains expression of a network of genes, which are known for frequent, marker-like expression in primary or cultured H/RS cells. Intriguingly, CD40, which is able to activate CD86 or Bcl-x(L) via NF-kappaB, is itself transcriptionally regulated by NF-kappaB through a promoter proximal binding site. NF-kappaB inhibition resulted in massive spontaneous and p53-independent apoptosis, which could be rescued by ectopic expression of Bcl-x(L), underscoring its dominant role in survival of H/RS cells. Hence, NF-kappaB controls a signaling network in H/RS cells, which promotes tumor cell growth and confers resistance to apoptosis.

Antigens, CD↗
PubMed2001

Fluorescently labeled model DNA sequences for exonucleolytic sequencing.

We describe here the enzyme-catalyzed, low-density labeling of DNAs with fluorescent dyes. Firstly, for "natural" template DNAs, dNTPs were partially substituted in the labeling reactions by the respective fluorophore-bearing analogs. The DNAs were labeled by PCR using Taq DNA polymerase. The covalent incorporation of dye-dNTPs decreased in the following order: rhodamine-green-5-dUTP (Molecular Probes, the Netherlands), tetramethylrhodamine-4-dUTP (FluoroRed, Amersham Pharmacia Biotech), Cy5-dCTP (Amersham Pharmacia Biotech). Exonucleolytic degradation by the 3'-->5' exonuclease activity of T7 DNA polymerase (wild type) in the presence of excess reduced thioredoxin proceeded to complete breakdown of the labeled DNAs. The catalytic cleavage constants determined by fluorescence correlation spectroscopy were between 0.5 and 1.5 s(-1) at 16 degrees C, normalized for the covalently incorporated dye-nucleotides. Secondly, rhodamine-green-X-dUTP (Roche Diagnostics), tetramethylrhodamine-6-dUTP (Roche Diagnostics), and Cy5-dCTP were covalently incorporated into the antisense strand of "synthetic" 218-b DNA template constructs (master sequences) at well defined positions, starting from the primer binding site, by total substitution for the naturally occurring dNTPs. The 218-b DNA constructs were labeled by PCR with a thermostable 3'-->5' exonuclease deficient mutant of the Tgo DNA polymerase which we have selected. The advantage of the special, synthetic DNA constructs as compared to natural DNAs lies in the possibility of obtaining tailor-made nucleic acids, optimized for testing the performance of exonucleolytic sequencing. The number of incorporated fluorescent nucleotides determined by complete exonucleolytic degradation and fluorescence correlation spectroscopy were six out of six possible incorporations for rhodamine-green-X-dUTP and tetramethylrhodamine-6-dUTP, respectively. Their covalent and base-specific incorporations were confirmed by the novel analysis methodology of re-sequencing (i.e. mobility-shift gel electrophoresis, reversion-PCR and re-sequencing) first developed in the paper Földes-Papp et al. (2001) and in this paper. This methodology was then used by other groups within the whole sequencing project.

Base Sequence↗
PubMed2001

Polymer support for exonucleolytic sequencing.

Different kinds of particles were investigated for their potential use as supports for exonucleolytic sequence analysis. Composite beads composed of an unreactive polystyrene "core" and a "shell" of functionalized silica nanoparticles were found to best fulfill the various prerequisites. The biotin/streptavidin system was used for attachment of DNA to composite beads of 6 microm diameter. Applying M13 ssDNA in extremely high dilution (approximately 1 molecule versus 100 beads) with internal fluorescent labels, only a small fraction of beads was found to be associated with fluorescent entities, which likely correspond to a very small number of bound DNA molecules per particle. For better selection and transfer of DNA-containing beads into microstructures for exonuclease degradation the loading experiments were repeated with composite beads of 2.3 microm diameter. In this case a covalent bond was formed between carboxylate-functionalized beads and amino-terminated oligonucleotides, which were detected through external labelling with fluorescent nanoparticles interacting with biotinylated segments of the complementary strand.

Biotin↗
PubMed2001

Studies on water transport through the sweet cherry fruit surface: II. Conductance of the cuticle in relation to fruit development.

Water conductance of the cuticular membrane (CM) of sweet cherry (Prunus avium L. cv. Sam) fruit during stages II and III (31-78 days after full bloom, DAFB) was investigated by gravimetrically monitoring water loss through segments of the exocarp. Segments were mounted in stainless-steel diffusion cells, filled with 0.5 ml of deionized water and incubated for 8 h at 25 +/- 2 degrees C over dry silica. Conductance was calculated by dividing the amount of water transpired per unit surface area and time by the difference in water vapor concentration across the segment (23.07 g m(-3) at 25 degrees C). Fruit mass and fruit surface area increased 4.9- and 2.8-fold between 31 and 78 DAFB, respectively. However, CM mass per unit area decreased from 3.9 to 1.5 g m(-2) and percentage of total wax content remained constant at about 31%. Stomatal density decreased from 0.8 to 0.2 mm(-2) (31-78 DAFB). Total conductance of the CM on the fruit cheek (gtot.) remained constant during stage II of development (approx. 1.38 x 10(-4) m s(-1) from 31 to 37 DAFB), increased to 1.73 x 10(-4) m s(-1) during early stage III of fruit growth (43-64 DAFB) then decreased to 0.95 x 10(-4) m s(-1) at maturity (78 DAFB). Partitioning gtot. into cuticular (gcut.) and stomatal conductance (gsto.) revealed that the relative contribution of gcut. to gtot. increased linearly from 30% to 87% of gtot. between 31 and 78 DAFB. respectively. On a whole-fruit basis, g,tot. and gcut. consistently increased up to 64 DAFB, and decreased thereafter. A significant negative linear relationship was obtained between gcut. and CM thickness, but not between the permeability coefficient (p) and CM thickness. Further, p was positively related to strain rate, suggesting that strain associated with expansion of the fruit surface increased p.

Algorithms↗
PubMed2001

Synthesis and localization of the mucin-associated TFF-peptides in the human uterus.

TFF-peptides (formerly P-domain peptides, trefoil factors) are typical secretory products of mucin-producing cells and are thought to influence the rheological properties of mucous gels. Here, the localization of these peptides in the human uterus was investigated. An analysis of TFF-peptides mRNA by the polymerase chain reaction revealed TFF3 mainly in the endocervix and smaller amounts in the endometrium. TFF1 and TFF2 mRNA was detectable occasionally in the endocervix and very rarely in the endometrium. Western blot analysis detected only TFF3 in tissue extracts of the endocervix and as a constituent of human cervical mucus. Immunofluorescence localized TFF3 in the surface epithelium of the endocervix and in gland-like structures of the cervical epithelium.

Blotting, Western↗
PubMed2000

IG-therasorb immunoapheresis in orthotopic xenotransplantation of baboons with landrace pig hearts.

BACKGROUND: The major problem of xenotransplantation is, that hyperacute xenograft rejection (HXR) causes graft failure within minutes or a few hours because of natural antibodies and activation of the complement system. As a preclinical model we transplanted pig hearts orthotopically into baboons. To prevent HXR after orthotopic xenotransplantation (oXHTx), the immunoglobulins (Ig) and natural antibodies were adsorbed to reusable Ig-Therasorb immunoadsorption (IA) columns. METHODS: We performed three oXHTx of landrace pig hearts into baboons (19+/-6.8 kg), using extracorporeal circulation (ECC) connected to the IA unit. After separating the recipient's blood into plasma and cellular fraction by a plasma filter, plasma flow was directed to the Ig-Therasorb column coated with polyclonal sheep-antibodies against human IgG, IgM, and IgA. Intraoperative treatment consisted of 4 cycles of IA. For a control, we transplanted one pig heart into a baboon (16.9 kg) without applying IA. Perioperatively, serum concentrations of Ig, anti-pig-antibodies, complement and cardiac enzymes were determined. Tissue samples of myocardium were collected at the end of the study for immunohistochemical examinations, light microscopic examination (LM) and electron microscopic examination (EM). For cardiac monitoring after oXHTx, we used ECG, echocardiography, and invasive measurement of cardiac output. To prevent a mismatch of donor and recipient heart size, the donor pig had a 30-40% lower body weight than the recipient baboon. RESULTS: Four cycles of IA removed >80% of IgG, IgM, and IgA from plasma. The graft of the control animal failed after 29 min. The first oXHTx with IA was intentionally terminated after 100 min, the second oXHTx after 11 hr and the third oXHTx after 21 hr. All xenografts showed no histological signs of HXR. After weaning off ECC, these donor hearts worked in sinus rhythm without electrocardiographic ST-segment elevation. An excellent cardiac output was measured by echocardiography and thermodilution (2 L/min). Serological parameters indicating cardiac damage were significantly lower after IA if compared with the control experiment. Macroscopically, the xenograft of the control animal showed massive hemorrhage in comparison with the almost inconspicuous grafts after IA. The myocardium of the IA group demonstrated fewer deposits of Ig and complement components compared with the control animal. CONCLUSION: Baboons do not hyperacutely reject a porcine xenograft after antibody depletion by the Ig-Therasorb column. In our experiment only 4 cycles of immunoapheresis effectively prevented HXR after oXHTx of baboons. The Ig-Therasorb column is a reusable device, which can be handled easily in combination with the ECC. IA must be tested in oXHTx longterm survival experiments, especially in combination with transgenic pig organs, which could be a reliable preclinical approach for future clinical xenotransplantation.

Animals↗
PubMed2000

Influence of ischemic time on hyperacute xenograft rejection of pig hearts in a working heart perfusion model with human blood.

In xenotransplantation long ischemic time of grafts is supposed to have a marked influence on hyperacute rejection (HXR). We investigated the influence of different cold ischemic times on HXR of ex vivo "working pig hearts" perfused with human blood. Xenoreactive natural antibodies (XNAb) as a trigger of HXR were eliminated by Ig-Therasorb immunoadsorption (IA). Explanted Landrace pig hearts of group G1 and group G3 (with additional IA) underwent 4 h of cold ischemia prior to xenoperfusion. Control groups G2 and G4 (with IA) were kept ischemic for only 46.6 +/- 15.8 and 51.2 +/- 4.2 min, respectively. Ischemic time prolonged the perfusion time in our working heart model (G1: 356 +/- 46.1 min; G2: 125 +/- 31 min; P < 0.05). IA had no additional impact on perfusion time but was effective by itself. The heart weight increased fourfold more in G2 as compared to the other groups. IA without ischemia significantly improved cardiac output in G4 (G3: 198.8 +/- 15.4 mL/min; G4: 338.5 +/- 16.0 mL/min). Coronary flow in G2 was significantly lower than in G1 (G1: 157.9 +/- 9.15 mL/min; G2: 59.4 +/- 20.1 mL/min). Histological signs of HXR (light and electron microscopy) could be found in G2 in contrast to the other groups. Parameters of serological damage showed a minimum in G4 and the maximum in G2. In G1 XNAb were nearly equally eliminated immediately after the start of xenoperfusion as in IA groups G4 and G3. Four hours of ischemic time showed beneficial effects in preventing HXR, possibly caused by changes of the endothelial cell surface (for example, glycosylation or loss of alpha1-3Gal epitopes with a hapten effect).

Acute Disease↗
PubMed2000

Prevention of hyperacute xenograft rejection in orthotopic xenotransplantation of pig hearts into baboons using immunoadsorption of antibodies and complement factors.

To prevent hyperacute xenograft rejection (HXR) caused by preformed natural antibodies (XNAb) after orthotopic heart xenotransplantation (oXHTx) of landrace pig hearts into baboons, we used immunoadsorption of immunoglobulins IgG, IgM and IgA and complement with the reusable Ig-Therasorb column. In addition to functional data, tissue was sampled for histological, immunohistochemical and electron microscopical analysis. We performed three oXHTx of landrace pig hearts to baboons using extracorporeal circulation (ECC) connected to the immunoadsorption unit. Intraoperative treatment consisted of four cycles of immunoabsorption (IA). One oXHTx of a baboon without IA served as a control. A mismatch of donor and recipient heart size was prevented by selecting a 30-40% lower body weight of donor pigs than recipients. Four cycles of IA removed more than 80% of IgG, IgM and IgA, 86% of antipig antibodies and 66% of complement factors C3 and C4 from plasma. The graft of the control animal failed after 29 min. Orthotopic xenotransplantation with IA was selectively terminated after 100 min, 11 h and 21 h, respectively without any histological signs of HXR in light and electron microscopy. After weaning off from ECC these donor xenografts showed sufficient function with normal ECG and excellent cardiac output in echocardiography and invasive measurement (1.93 +/- 0.035 l/min). The myocardium of the control xenograft demonstrated more deposits of Ig and complement components (C3, C4) than in the IA group. Baboons survive HXR after orthotopic pig heart xenotransplantation due to antibody depletion by reusable Ig-Therasorb column treatment. Long-term survival in an orthotopic baboon xenotransplantation model after IA, especially in combination with transgenic pig organs, could be a reliable preclinical trial for future clinical xenotransplantation programs.

Acute Disease↗
PubMed2000

Studies on water transport through the sweet cherry fruit surface: characterizing conductance of the cuticular membrane using pericarp segments.

Water conductance of the cuticular membrane (CM) of mature sweet cherry fruit (Prunus avium L. cv. Sam) was investigated by monitoring water loss from segments of the outer pericarp excised from the cheek of the fruit. Segments consisted of epidermis, hypodermis and several cell layers of the mesocarp. Segments were mounted in stainless-steel diffusion cells with the mesocarp surface in contact with water, while the outer cuticular surface was exposed to dry silica (22 +/- 1 degrees C). Conductance was calculated by dividing the amount of water transpired per unit area and time by the difference in water vapour concentration across the segment. Conductance values had a log normal distribution with a median of 1.15 x 10(-4) m s(-1) (n=357). Transpiration increased linearly with time. Conductance remained constant and was not affected by metabolic inhibitors (1 mM NaN3 or 0.1 mM carbonylcyanide m-chlorophenylhydrazone) or thickness of segments (range 0.8-2.8 mm). Storing fruit (up to 42 d, 1 degrees C) used as a source of segments had no consistent effect on conductance. Conductance of the CM increased from cheek (1.16 +/- 0.10 x 10(-4) m s(-1)) to ventral suture (1.32 +/- 0.07 x 10(-4) m s(-1)) and to stylar end (2.53 +/- 0.17 x 10(-4) m s(-1)). There was a positive relationship (r2=0.066**; n=108) between conductance and stomatal density. From this relationship the cuticular conductance of a hypothetical astomatous CM was estimated to be 0.97 +/- 0.09 x 10(-4) m s(-1). Removal of epicuticular wax by stripping with cellulose acetate or extracting epicuticular plus cuticular wax by dipping in CHCl3/methanol increased conductance 3.6- and 48.6-fold, respectively. Water fluxes increased with increasing temperature (range 10-39 degrees C) and energies of activation, calculated for the temperature range from 10 to 30 degrees C, were 64.8 +/- 5.8 and 22.2 +/- 5.0 kJ mol(-1) for flux and vapour-concentration-based conductance, respectively.

Biological Transport↗
PubMed2000

Clinical performance and periodontal outcome of temporary crowns and fixed partial dentures: A randomized clinical trial.

STATEMENT OF PROBLEM: Different materials (autopolymerizing, dual curing, and light initiated) are used for fabricating provisional restorations during prosthetic treatment. Randomized clinical trials that have evaluated these provisional materials have not been published. PURPOSE: This clinical trial compared the handling, fitting, plaque adherence, gingivitis, color stability, and the subjective assessment of the provisional materials by the patient and the dentist for 2 autopolymerizing (Protemp, Luxatemp), 1 dual-curing (Provipont), and 1 light-initiated (Triad-VLC) material for the manufacturing of temporary crowns and fixed partial dentures. MATERIAL AND METHODS: Thirty subjects in need of 2 similar fixed prosthetic restorations (single crowns ¿20, three-quarter crowns ¿2, connected crowns ¿9, or fixed partial dentures ¿30) were treated with 1 temporary restoration of Protemp II (control) and one randomly selected from Luxatemp, Provipont, or Triad-VLC materials. The mean time of treatment was 37.5 days (minimum 2 days, maximum 156 days). All restorations were manufactured intraorally with a vacuum-formed template. RESULTS: Mechanical and retentive characteristics revealed a high level of clinical reliability. Plaque adherence of the teeth with temporary restorations was significantly increased (P =.0039) compared with the untreated mesial reference teeth. CONCLUSION: The advantageous mechanical properties of the light-curing and dual-curing materials reviewed in dental literature were clinically offset by disadvantages in handling.

Chi-Square Distribution↗