Exploring complications following cranioplasty after decompressive hemicraniectomy: A retrospective bicenter assessment of autologous, PMMA and CAD implants.

Cranioplasty (CP) after decompressive hemicraniectomy (DHC) is a common neurosurgical procedure with a high complication rate. The best material for the repair of large cranial defects is unclear. The aim of this study was to evaluate different implant materials regarding surgery related complications after CP. Type of materials include the autologous bone flap (ABF), polymethylmethacrylate (PMMA), calcium phosphate reinforced with titanium mesh (CaP-Ti), polyetheretherketone (PEEK) and hydroxyapatite (HA). A retrospective, descriptive, observational bicenter study was performed, medical data of all patients who underwent CP after DHC between January 1st, 2016 and December 31st, 2022 were analyzed. Follow-up was until December 31st, 2023. 139 consecutive patients with a median age of 54 years who received either PMMA (56/139; 40.3%), PEEK (35/139; 25.2%), CaP-Ti (21/139; 15.1%), ABF (25/139; 18.0%) or HA (2/139; 1.4%) cranial implant after DHC were included in the study. Median time from DHC to CP was 117 days and median follow-up period was 43 months. Surgical site infection was the most frequent surgery-related complication (13.7%; 19/139). PEEK implants were mostly affected (28.6%; 10/35), followed by ABF (20%; 5/25), CaP-Ti implants (9.5%; 2/21) and PMMA implants (1.7%, 1/56). Explantation was necessary for 9 PEEK implants (25.7%; 9/35), 6 ABFs (24.0%; 6/25), 3 CaP-Ti implants (14.3%; 3/21) and 4 PMMA implants (7.1%; 4/56). Besides infection, a postoperative hematoma was the most common cause. Median surgical time was 106 min, neither longer surgical time nor use of anticoagulation were significantly related to higher infection rates (p = 0.547; p = 0.152 respectively). Ventriculoperitoneal shunt implantation prior to CP was noted in 33.8% (47/139) and not significantly associated with surgical related complications. Perioperative lumbar drainage, due to bulging brain, inserted in 38 patients (27.3%; 38/139) before surgery was protective when it comes to explantation of the implant (p = 0.035). Based on our results, CP is still related to a relatively high number of infections and further complications. Implant material seems to have a high effect on postoperative infections, since surgical time, anticoagulation therapy and hydrocephalus did not show a statistically significant effect on postoperative complications in this study. PEEK implants and ABFs seem to possess higher risk of postoperative infection. More biocompatible implants such as CaP-Ti might be beneficial. Further, prospective studies are necessary to answer this question.

Eating disorder professionals' perceptions of oral health knowledge.

OBJECTIVE: The aim of this study was to assess the oral health knowledge among professionals who specialize in treating eating disorders, and identify to what extent their education, and training addresses oral health care delivery, and recommendations for individuals with eating disorders. METHOD: Participants for this study were licensed behavioural and medical providers specializing in eating disorder treatment (n = 107), and recruited through professional eating disorder organizations. Participants completed an anonymous, online questionnaire (33 items) assessing level of oral health-related education, knowledge and treatment recommendations within the participant's respective eating disorder discipline. RESULTS: The majority of respondents (85%) were formally trained in eating disorders, and of those trained, 64.4% were not satisfied with the level of oral health education during formal education, and 19.5% report no oral health education. Respondents consider their knowledge of risk of oral disease for their clients/patients as average or above (84%), and ranked tooth erosion as the greatest reason for oral care (63%) while dry mouth led in the rankings for least significant reason for oral care (33%). Referral for oral care was found to be more common after reports of complication (55%). DISCUSSION: According to these findings, eating disorder professionals regard oral health care for their clients as significant, and may be unaware of associated oral risk factors, current oral care standards and long-term oral effects of disordered eating apart from enamel erosion.

Biocompatibility of haemodialysis membranes determined by gene expression of human leucocytes: a crossover study.

BACKGROUND: Biocompatibility of haemodialysis membranes is the most important quality criteria to enable long-term dialysis without major harmful effects. This study sought to evaluate the differences of genomic signatures derived from peripheral blood mononuclear cells (PBMC) in patients undergoing haemodialysis treatment using two different dialyser membranes: one semi-synthetic and one full-synthetic membrane. DESIGN: Microarray experiments were conducted in PBMCs of four stable haemodialysis patients before and after dialysis comparing semi-synthetic (Hemophan GFS Plus 16) and full-synthetic (Hemoflow FX80) dialysis membranes, respectively. Genes differentially expressed when comparing the two different membranes used were analysed in order to elucidate the underlying molecular mechanisms affecting PBMCs in the course of dialysis treatment. RESULTS: One hundred and seventy-two genes were identified as up-regulated after treatment with semi-synthetic membranes when compared to full-synthetic membranes. These genes could be assigned to processes including immunity and defence, signal transduction, and apoptosis. Dialysis with a full-synthetic membrane, on the other hand, led to an activation of 72 genes that were mainly involved in cell cycle and cell cycle control. CONCLUSION: The over-representation of genes belonging to immunity/defence, signal transduction, and apoptosis as found with semi-synthetic membranes suggests that full-synthetic membranes are more biocompatible than semi-synthetic membranes.

Characterization of stationary phases for gas chromatography by 29Si NMR spectroscopy. II. Silphenylene-siloxane copolymers.

A series of tetramethyl-p-silphenylene-siloxane copolymers with dimethyl, 1H,1H,2H,2H-perfluorodecylmethyl and diphenyl siloxy groups was prepared. 1H and 29Si nuclear magnetic resonance spectroscopy showed that the chosen reaction conditions provided polymers with diphenyl content up to 85%. The theoretical content of the monomer units correlated well with the measured content. Signal assignments of the copolymers and their corresponding chemical shifts are summarized. Information about alternating, randomized or block sequences was obtained by 29Si nuclear magnetic resonance spectroscopy. Limitations of the method for the determination of microstructure parameters are discussed.

Masseter contracture and tachycardia causing termination of anesthesia.

A careful preoperative history can be helpful in detecting problems with previous anesthetic experiences. However, it has been found that in the patients who have developed a complete syndrome of malignant hyperthermia (MH), 30% had prior uneventful general anesthesia. It is therefore of extreme importance when delivering anesthesia to recognize the signs of MH early in order to initiate correct procedures to prevent the development of a fulminating crisis of MH.

In vitro--transcriptional response of polymorphonuclear leukocytes following contact with different antigens.

Background Human polymorphonuclear neutrophils (PMN) are activated and undergo apoptosis if brought into contact with cuprophane haemodialysis membranes, a phenomenon not observed if more 'biocompatible' polysulfone dialysers are used. It remains yet to be defined if this differential response is due to mechanisms regulated on a transcriptional or protein level. Furthermore, it is not clear if the contact of PMN with membranes ('frustrated' phagocytosis) activates the same response as phagocytosis of bacteria (complete phagocytosis). Materials and methods We performed a genome-wide differential gene expression study using cDNA microarrays to analyse the impact of different dialysis fibres on the transcriptional response of PMN of human healthy volunteers. These results were compared to transcriptional response of PMN during phagocytosis of Escherichia coli. Results We did not detect significant differences in gene expression between PMN stimulated with cuprophane or pulysulfone. Compared to unstimulated PMN the 'frustrated' phagocytosis of either dialysis membrane resulted in increased expression of 50 genes, with a marked up-regulation of FOS - and JUN - transcripts, but with only little activation of immune response genes, and virtually no activation of apoptosis related RNA transcripts. In contrast, phagocytosis of E.coli was associated with a striking up-regulation of 88 genes, most of them involved in pro- and antiapoptotic pathways, immune response and activation of nuclear factor kappa B and inhibitor of NF-kappa B. Conclusions Our results suggest that the response of PMN to artificial surfaces is not controlled on transcriptional level. Complete and 'frustrated' phagocytosis activate markedly distinct transcriptional regulatory pathways in PMN.

[Reflections on the use of fluid dimethylpolysiloxan in plastic surgery of the head and neck]. / Uberlegungen zur Anwendung von flüssigem Dimethylpolysiloxan in der plastischen Kopf-und Halschirurgie.

The authors present retrospectively results and complications of 47 treatments with fluid dimethylpolysiloxane (silicone). The injections were not administered in the author's surgical department. The history of fluid silicone, its tissue reactions and the aesthetic results obtained are described. Different types of complications and their management are discussed. According to the authors' experience fluid dimethylpolysiloxane has not proved to be a proper material for plastic reconstructive and aesthetic treatment in the head and neck region.

[Reconstruction of the lower third of the face--microsurgical monobloc transfer with vascularized bone]. / Aufbau des unteren Gesichtsdrittels. Mikrochirurgischer Monobloc-Transfer mit vaskularisiertem Knochen.

The authors present two microsurgical options of the reconstruction of the lower third of the face. They outline a systematisation of indications and techniques and emphasise versatility and flexibility of free flaps compared to pedicled flaps, and describe the advantages of the vascularisation and the techniques of the iliac crest osteocutaneous flap and the parascapular cutaneous-latissimus dorsi osteomyocutaneous flap which was developed by Nassif.

Ansatz for dynamical hierarchies.

Complex, robust functionalities can be generated naturally in at least two ways: by the assembly of structures and by the evolution of structures. This work is concerned with spontaneous formation of structures. We define the notion of dynamical hierarchies in natural systems and show the importance of this particular kind of organization for living systems. We then define a framework that enables us to formulate, investigate, and manipulate such dynamical hierarchies. This framework allows us to simultaneously investigate different levels of description together with their interrelationship, which is necessary to understand the nature of dynamical hierarchies. Our framework is then applied to a concrete and very simple formal, physicochemical, dynamical hierarchy involving water and monomers at level one, polymers and water at level two, and micelles (polymer aggregates) and water at level three. Formulating this system as a simple two-dimensional molecular dynamics (MD) lattice gas allows us within one dynamical system to demonstrate the successive emergence of two higher levels (three levels all together) of robust structures with associated properties. Second, we demonstrate how the framework for dynamical hierarchies can be used for realistic (predictive) physicochemical simulation of molecular self-assembly and self-organization processes. We discuss the detailed process of micellation using the three-dimensional MD lattice gas. Finally, from these examples we can infer principles about formal dynamical hierarchies. We present an ansatz for how to generate robust, higher-order emergent properties in formal dynamical systems that is based on a conjecture of a necessary minimal complexity within the fundamental interacting structures once a particular simulation framework is chosen.

Effects of rotary instruments and ultrasonic irrigation on debris and smear layer scores: a scanning electron microscopic study.

AIM: This study evaluated debris and smear layer scores after two types of instruments manufactured from different alloys were used to ultrasonically activate irrigants during canal preparation. The influence of two rotary preparation techniques on cleanliness of the shaped canals was also studied. METHODOLOGY: Apical stops were prepared to size 45 in 42 single-canalled extracted premolars and canines, which were divided into six equal groups. Groups 1, 2 and 3 were prepared by ProFile.04 (PF) while groups 4, 5 and 6 were prepared by Lightspeed (LS). All groups were irrigated using 5.25% NaOCl and 17% EDTA. Irrigants in groups 2 and 5 were ultrasonically activated using a size 15 steel K-file and by a blunt flexible nickel-titanium wire in groups 3 and 6. Groups 1 and 4 served as negative controls. Roots were split and canal walls examined at 15x, 200x and 400x magnification in an SEM. Smear layer and debris scores were recorded at 3, 6 and 9 mm levels using a 5-step scoring scale and a 200- micro m grid. Means were tested for significance using nonparametric Mann-Whitney U and Kruskal-Wallis tests. RESULTS: Debris and smear layer scores for the six groups varied from 1.98 +/- 1.04 to 3.47 +/- 0.97 and from 1.37 +/- 0.4 to 2.36 +/- 0.99, respectively. Although all groups had significantly higher smear layer and debris scores at the 3 mm levels compared to the 9 mm levels (P < 0.05), no significant differences were recorded due to the ultrasonic energy transmitted by the two alloys. CONCLUSION: Ultrasonically activated irrigants did not reduce debris or smear layer scores. This finding was not influenced by the material nor by the design of the instrument used to transmit ultrasonic activation.

[Duplex sonographic monitoring of infra-inguinal arterial reconstructions: can a threatened bypass occlusion be detected by this method?]. / Duplexsonographische Uberwachung von infrainguinalen arteriellen Rekonstruktionen: Kann dadurch ein drohender Bypassverschluss erkannt werden?

In our institution, 95 infrainguinal arterial reconstructions were prospectively entered into a graft surveillance programme which consisted of a postoperative i.a. DSA and routine assessment of graft flow velocity (GFV) and ankle pressure indices (ABI) during the first postoperative year. An average of 4.1 GFV measurements was obtained during a mean follow-up period of 8.2 months. Abnormal GFV led to arteriography in 29 bypasses identifying--aside from three false positive findings--two graft occlusions and 24 severe (> 70%) graft stenoses. Of the latter, in only 7 cases a significant decrease in ABI was found. Unheralded graft occlusion occurred in 6 patients. Including the corrections of the above mentioned lesions, secondary patency rates were 97% at 30 days and 89% at one year.

Selective assembly of cyclodextrins on poly(ethylene oxide)-poly(propylene oxide) block copolymers.

This paper presents a computational study on the formation of a molecular necklace formed by specific threading of cyclodextrins (CDs) on block copolymers. Structural as well as energetic principles for the selective complexation of alpha- and beta-cyclodextrin with poly(ethylene oxide)-poly(propylene oxide) block copolymers (PEO-PPO) are elucidated considering a diblock copolymer of equimolecular composition (PEO)4-(PPO)4 as guest. A non-statistical distribution of CDs, i.e. alpha-CDs primarily located on the PEO chain and beta-CDs on PPO blocks of the polymer, is based on a variety of structural features and energetic preferences considering both potential as well as solvation energies. This selectivity becomes already obvious considering 1:1 complexes between PEO and PPO monomers and the two CDs, but is increasingly evident when calculating higher order ensembles. Besides the host-guest interaction, docking between CDs themselves is an important, also non-statistical, prerequisite for the self-assembly of highly ordered tubes. The formation of intermolecular hydrogen bonds between adjacent CDs in a tubular aggregate gives an important contribution to the overall stability of the molecular necklace. The net effect, based on the preferential interaction between host and guest as well as between the host molecules themselves, results in the formation of a stable, highly ordered macromolecular, multicomponent aggregate.

[Lipomatous atrophy of the parotid gland in chronic alcohol consumption]. / Lipomatöse atrophie der Glandula parotis bei chronischem Alkoholkonsum.

The effect of chronic ethanol consumption on the morphology of the rat parotid gland was investigated. After feeding an ethanol diet containing 36% of total calories as ethanol for 90 days light microscopic and electron microscopic investigations of the parotid gland tissue showed a striking fat accumulation compared to control rats. Besides interstitial fat tissue dispositions, fat droplets of various size occurred in most of the acinar cells. Additional morphometric investigations revealed a decrease in mean acinar cell volume (-21.9% p greater than 0.001). The latter finding reflects an atrophy of the secretory parenchyma and appears to be responsible for the impaired saliva secretion after chronic ethanol consumption which has been observed in former studies.

High-throughput fluorescence screening of antioxidative capacity in human serum.

Diphenylhexatriene-labeled phosphatidylcholine and propionic acid have been established as selective fluorescence markers for the continuous determination of oxidation processes in the lipid and aqueous phases of unfractionated human serum. Oxidation of the respective fluorophores leads to a decrease in fluorescence intensity from which the time-dependent degradation of the marker molecule can be determined. The lag times preceding the propagation of oxidation are representative for the antioxidative capacity of the system, which may be influenced by exogenous factors, e.g., the antioxidants from the diet. Supplementation of human serum by quercetin, rutin, vitamin E, vitamin C, or total apple phenolics in vitro led to a decrease in oxidizability depending on the oxidation marker and the hydrophobicity of the antioxidant. Quercetin and vitamin E showed a higher in vitro capacity of protecting lipoproteins against oxidation. In contrast, rutin and vitamin C were more efficient as inhibitors in the aqueous phase. The same effect on serum was found after dietary consumption of apples. This result is in line with the known observation that intake of plant polyphenols leads to an increase in serum levels of hydrophilic antioxidants.

[The subjective and objective assessment of the functional treatment results after combined orthodontic and oral surgical measures]. / Subjektive und objektive Bewertung der funktionellen Behandlungsergebnisse nach kombiniert kieferorthopädisch-kieferchirurgischen Massnahmen.

The status of temporomandibular joint and muscle function was examined in a group of 22 adult patients, who underwent combined orthodontic and surgical treatment. Even though nearly all patients were very content with the results of the therapy, 2/3 showed a rather reduced movement of the condyle after mandibular sagittal split osteotomy. The causing factors are: arthrosis, permanent displacement of the disc or a change of muscle function after surgery.