Surgical denervation of the thumb CMC joint: anatomy, technique.

Surgical denervation of the thumb carpometacarpal (CMC) joint is a theoretical surgical option for thumb CMC arthritis. Some authors have described the nerve branches of thumb CMC joint. We present the innervation of the thumb CMC joint (thenar - recurrent - branch of median nerve, palmar branch of median nerve, superficial branch of radial nerve, lateral cutaneous nerve of forearm, deep branch of ulnar nerve) and the surgical techniques to achieve optimal denervation of this joint. While the results have been disappointing, this technique may be combined with conservative surgical procedures (synovectomy, ligament reconstruction) and it allows more invasive surgery in the future if necessary.

Proteotyping of laboratory-scale biogas plants reveals multiple steady-states in community composition.

Complex microbial communities are the functional core of anaerobic digestion processes taking place in biogas plants (BGP). So far, however, a comprehensive characterization of the microbiomes involved in methane formation is technically challenging. As an alternative, enriched communities from laboratory-scale experiments can be investigated that have a reduced number of organisms and are easier to characterize by state of the art mass spectrometric-based (MS) metaproteomic workflows. Six parallel laboratory digesters were inoculated with sludge from a full-scale BGP to study the development of enriched microbial communities under defined conditions. During the first three month of cultivation, all reactors (R1-R6) were functionally comparable regarding biogas productions (375-625 NL Lreactor volume-1 d-1), methane yields (50-60%), pH values (7.1-7.3), and volatile fatty acids (VFA, <5 mM). Nevertheless, a clear impact of the temperature (R3, R4) and ammonia (R5, R6) shifts was observed for the respective reactors. In both reactors operated under thermophilic regime, acetic and propionic acid (10-20 mM) began to accumulate. While R4 recovered quickly from acidification, the levels of VFA remained to be high in R3 resulting in low pH values of 6.5-6.9. The digesters R5 and R6 operated under the high ammonia regime (>1 gNH3 L-1) showed an increase to pH 7.5-8.0, accumulation of acetate (>10 mM), and decreasing biogas production (<125 NL Lreactor volume-1 d-1). Tandem MS (MS/MS)-based proteotyping allowed the identification of taxonomic abundances and biological processes. Although all reactors showed similar performances, proteotyping and terminal restriction fragment length polymorphisms (T-RFLP) fingerprinting revealed significant differences in the composition of individual microbial communities, indicating multiple steady-states. Furthermore, cellulolytic enzymes and cellulosomal proteins of Clostridium thermocellum were identified to be specific markers for the thermophilic reactors (R3, R4). Metaproteins found in R3 indicated hydrogenothrophic methanogenesis, whereas metaproteins of acetoclastic methanogenesis were identified in R4. This suggests not only an individual evolution of microbial communities even for the case that BGPs are started at the same initial conditions under well controlled environmental conditions, but also a high compositional variance of microbiomes under extreme conditions.

Bilateral carpal tunnel surgery in one operation: Retrospective study.

Carpal tunnel syndrome is the most common entrapment syndrome. The incidence of a bilateral condition varies between 22% and 87%. The aim of our study was to assess the level of satisfaction and the clinical outcomes in a group of patients operated on through a bilateral neurolysis on the median nerve in the carpal tunnel, in one operating session. This is a retrospective study involving patients with an electromyographic and clinical diagnosis of bilateral carpal tunnel syndrome. Patients were treated on an outpatient basis and the bilateral neurolysis was performed by endoscopy. The postoperative data was collected during consultation by a senior surgeon or during telephone interviews. Patients were asked to respond to a satisfaction questionnaire and the functional outcome was assessed through the Quick-Disabilities of the Arm, Shoulder, and Hand (Quick-DASH) questionnaire. Twenty-nine patients with bilateral carpal tunnel syndrome were operated on in single operating sessions between January 2009 and January 2014. The average follow-up was 46 months. The average age at the time of the intervention was 45 years. Two patients were lost to follow-up, and 27 were able to be assessed. In relation to the clinical and functional outcomes, the average Quick-DASH score was 6.78 (ranges: 0-43.2). Twenty-five patients (92.5%) were satisfied with this simultaneous treatment and 26 patients (96%) would choose the same technique again. One-stage surgery in cases of bilateral carpal tunnel syndrome appears to constitute a benefit for the patient, the surgeon and the anaesthetist, but it is reserved for patients who request it and who are motivated by this type of intervention.

Proteotyping of biogas plant microbiomes separates biogas plants according to process temperature and reactor type.

BACKGROUND: Methane yield and biogas productivity of biogas plants (BGPs) depend on microbial community structure and function, substrate supply, and general biogas process parameters. So far, however, relatively little is known about correlations between microbial community function and process parameters. To close this knowledge gap, microbial communities of 40 samples from 35 different industrial biogas plants were evaluated by a metaproteomics approach in this study. RESULTS: Liquid chromatography coupled to tandem mass spectrometry (Orbitrap Elite™ Hybrid Ion Trap-Orbitrap Mass Spectrometer) of all 40 samples as triplicate enabled the identification of 3138 different metaproteins belonging to 162 biological processes and 75 different taxonomic orders. The respective database searches were performed against UniProtKB/Swiss-Prot and seven metagenome databases. Subsequent clustering and principal component analysis of these data allowed for the identification of four main clusters associated with mesophile and thermophile process conditions, the use of upflow anaerobic sludge blanket reactors and BGP feeding with sewage sludge. Observations confirm a previous phylogenetic study of the same BGP samples that was based on 16S rRNA gene sequencing by De Vrieze et al. (Water Res 75:312-323, 2015). In particular, we identified similar microbial key players of biogas processes, namely Bacillales, Enterobacteriales, Bacteriodales, Clostridiales, Rhizobiales and Thermoanaerobacteriales as well as Methanobacteriales, Methanosarcinales and Methanococcales. For the elucidation of the main biomass degradation pathways, the most abundant 1 % of metaproteins was assigned to the KEGG map 1200 representing the central carbon metabolism. Additionally, the effect of the process parameters (i) temperature, (ii) organic loading rate (OLR), (iii) total ammonia nitrogen (TAN), and (iv) sludge retention time (SRT) on these pathways was investigated. For example, high TAN correlated with hydrogenotrophic methanogens and bacterial one-carbon metabolism, indicating syntrophic acetate oxidation. CONCLUSIONS: This is the first large-scale metaproteome study of BGPs. Proteotyping of BGPs reveals general correlations between the microbial community structure and its function with process parameters. The monitoring of changes on the level of microbial key functions or even of the microbial community represents a well-directed tool for the identification of process problems and disturbances.Graphical abstractCorrelation between the different orders and process parameter, as well as principle component analysis of all investigated biogas plants based on the identified metaproteins.

Sialic acid-specific affinity chromatography for the separation of erythropoietin glycoforms using serotonin as a ligand.

Recombinant human erythropoietin (rhEPO) is an important CHO cell-derived glycoprotein and the degree of sialylation of this hormone is crucial for its in vivo bioactivity. In order to improve the purification process serotonin as a potential affinity ligand was tested for preparative chromatographic separation of rhEPO glycoforms into fractions of different degrees of sialylation. Therefore, two chromatographic matrices were prepared by immobilizing serotonin on CNBr- and NHS-Sepharose™. First it was shown both matrices bind rhEPO only in its sialylated form. Results indicate that binding is pH independent between pH 3.5 to 8 suggesting it is not only based on electrostatic interactions. Second, after optimal binding conditions were identified, semi-purified rhEPO was loaded onto both matrices and eluted using a stepwise elution gradient of sodium chloride. For comparison same affinity purification experiments were performed using wheat germ agglutinin-coupled agarose, a lectin known for its affinity towards sialylated glycoproteins. To monitor changes in N-glycan fingerprint, eluate fractions were analyzed by multiplexed capillary gel electrophoresis coupled to laser-induced fluorescence (xCGE-LIF). For the serotonin matrices an increasing degree of sialylation was observed from the first to the third elution fraction while purity of rhEPO could be increased at the same time. The late elution fractions of serotonin-coupled CNBr- and NHS-Sepharose™ also showed an overall sialylation degree exceeding that of the starting material. In contrast, for rhEPO bound to wheat germ agglutinin-coupled agarose, no distinct change in the degree of sialylation could be observed after elution. Overall, these encouraging results highlight the potential of serotonin as a chromatographic ligand for the improvement of pharmaceutical purification processes of rhEPO.

Sample prefractionation with liquid isoelectric focusing enables in depth microbial metaproteome analysis of mesophilic and thermophilic biogas plants.

Biogas production from energy crops and biodegradable waste is one of the major sources for renewable energies in Germany. Within a biogas plant (BGP) a complex microbial community converts biomass to biogas. Unfortunately, disturbances of the biogas process occur occasionally and cause economic losses of varying extent. Besides technical failures the microbial community itself is commonly assumed as a reason for process instability. To improve the performance and efficiency of BGP, a deeper knowledge of the composition and the metabolic state of the microbial community is required and biomarkers for monitoring of process deviations or even the prediction of process failures have to be identified. Previous work based on 2D-electrophoresis demonstrated that the analysis of the metaproteome is well suited to provide insights into the apparent metabolism of the microbial communities. Using SDS-PAGE with subsequent mass spectrometry, stable protein patterns were evaluated for a number of anaerobic digesters. Furthermore, it was shown that severe changes in process parameters such as acidification resulted in significant modifications of the metaproteome. Monitoring of changing protein patterns derived from anaerobic digesters, however, is still a challenge due to the high complexity of the metaproteome. In this study, different combinations of separation techniques to reduce the complexity of proteomic BGP samples were compared with respect to the subsequent identification of proteins by tandem mass spectrometry (MS/MS): (i) 1D: proteins were tryptically digested and the resulting peptides were separated by reversed phase chromatography prior to MS/MS. (ii) 2D: proteins were separated by GeLC-MS/MS according to proteins molecular weights before tryptic digestion, (iii) 3D: proteins were separated by gel-free fractionation using isoelectric focusing (IEF) conducted before GeLC-MS/MS. For this study, a comparison of two anaerobic digesters operated at mesophilic and at thermophilic conditions was conducted. The addition of further separation dimensions before protein identification increased the number of identified proteins. On the other hand additional fractionation steps increased the experimental work load and the time required for LC-MS/MS measurement. The high resolution of the 3D-approach enabled the detection of approximately 750 to 1650 proteins covering the main pathways of hydrolysis, acidogenesis, acetogenesis and methanogenesis. Methanosarcinales dominated in the mesophilic BGP, whereas Methanomicrobiales were highly abundant in the thermophilic BGP. Pathway analysis confirmed the taxonomic results and revealed that the acetoclastic methanogenesis occurred preferentially at mesophilic conditions, whereas exclusively hydrogenotrophic methanogenesis was detected in thermophilic BGP. However, for the identification of process biomarkers by comprehensive screening of BGP it will be indispensable to find a balance between the experimental efforts and analytical resolution.

Quantitative mapping of glycoprotein micro-heterogeneity and macro-heterogeneity: an evaluation of mass spectrometry signal strengths using synthetic peptides and glycopeptides.

Mass spectrometry has made possible the field of proteomics and become an invaluable tool for identifying and quantifying post-translational modifications of proteins from complex mixtures. Because PTMs are recognized as key factors of biological activity, reliable PTM characterization is essential to understanding the relationship between protein isoform and activity. Protein glycosylations, in particular, can be especially difficult to characterize due to the range of different oligosaccharide entities that may be attached at any particular site. In this month' Special Feature Dr Daniel Kolarich of the Dept. of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces and his collaborators point out that quantitative label-free glycoproteomics can yield information about glycoprotein microand macroheterogeniety if the tools are sufficiently accurate. To understand and characterize the performance capability of MS tools they synthesized a panel of peptides and their glycopeptide derivatives as references and used these to investigate the qualitative and quantitative results from various ionization techniques and mass analyzers.

Metaproteome analysis of the microbial communities in agricultural biogas plants.

In biogas plants agricultural waste and energy crops are converted by complex microbial communities to methane for the production of renewable energy. In Germany, this process is widely applied namely in context of agricultural production systems. However, process disturbances, are one of the major causes for economic losses. In addition, the conversion of biomass, in particular of cellulose, is in most cases incomplete and, hence, insufficient. Besides technical aspects, a more profound characterization concerning the functionality of the microbial communities involved would strongly support the improvement of yield and stability in biogas production. To monitor these communities on the functional level, metaproteome analysis was applied in this study to full-scale agricultural biogas plants. Proteins were extracted directly from sludge for separation by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and subsequent identification with mass spectrometry. Protein profiles obtained with SDS-PAGE were specific for different biogas plants and often stable for several months. Differences of protein profiles were visualized by clustering, which allowed not only the discrimination between mesophilic and thermophilic operated biogas plants but also the detection of process disturbances such as acidification. In particular, acidification of a biogas plant was detected in advance by disappearance of major bands in SDS-PAGE. Identification of proteins from SDS-PAGE gels revealed that methyl CoM reductase, which is responsible for the release of methane during methanogenesis, from the order Methanosarcinales was significantly decreased. Hence, it is assumed that this enzyme might be a promising candidate to serve as a predictive biomarker for acidification.

High-density microcarrier cell cultures for influenza virus production.

Influenza virus A/PR/8/34 virus propagation in adherent Madin-Darby canine kidney cells in high-density microcarrier cultures is described. To improve virus yields, perfusion and repeated fed-batch modes were applied using cell-specific feed rates. Cell densities up to 1.1 × 10(7) cells/mL were achieved. Cell-specific virus yields in high-density cultures were at similar levels compared with standard, low-density cultivations. In the average 2,400 and 3,300 virions per cell were obtained for two variants of the virus strain A/PR/8/34, PR8-National Institute for Biological Standards and Control (NIBSC) and PR8-Robert Koch Institute, respectively. Maximum virus titer (HA activity = 1,778 HAU/100 µL) for virus variant PR8-NIBSC was obtained for a cultivation infected before maximum cell concentration was reached.

Tobacco smoke: a critical etiological factor for vascular impairment at the blood-brain barrier.

Active and passive tobacco smoke are associated with the dysfunction of endothelial physiology and vascular impairment. Studies correlating the effects of smoking and the brain microvasculature at the blood-brain barrier (BBB) level have been largely limited to few selective compounds that are present in the tobacco smoke (TS) yet the pathophysiology of smoking has not been unveiled. For this purpose, we characterized the physiological response of isolated human brain microvascular endothelial cells (HBMEC) and monocytes to the exposure of whole soluble TS extract. With the use of a well established humanized flow-based in vitro blood-brain barrier model (DIV-BBB) we have also investigated the BBB physiological response to TS under both normal and impaired hemodynamic conditions simulating ischemia. Our results showed that TS selectively decreased endothelial viability only at very high concentrations while not significantly affecting that of astrocytes and monocytes. At lower concentrations, despite the absence of cytotoxicity, TS induced a strong vascular pro-inflammatory response. This included the upregulation of endothelial pro-inflammatory genes, a significant increase of the levels of pro-inflammatory cytokines, activated matrix metalloproteinase, and the differentiation of monocytes into macrophages. When flow-cessation/reperfusion was paired with TS exposure, the inflammatory response and the loss of BBB viability were significantly increased in comparison to sham-smoke condition. In conclusion, TS is a strong vascular inflammatory primer that can facilitate the loss of BBB function and viability in pathological settings involving a local transient loss of cerebral blood flow such as during ischemic insults.

[Double trypanosomal chancre revealing West African trypanosomiasis in a Frenchman living in Gabon]. / Chancres cutanés révélant une trypanosomose africaine à Trypanosoma brucei gambiense chez un résident français au Gabon.

BACKGROUND: Human African trypanosomiasis (sleeping sickness), an endemic disease, is currently reemerging in Africa with an estimated incidence of 45,000 new cases per year. It is caused by Trypanosoma brucei subspecies and transmitted by day-biting tsetse flies. PATIENTS AND METHODS: We report a case of West African trypanosomiasis due to Trypanosoma brucei gambiense involving a Frenchman living in Libreville, Gabon. The patient presented with fever and polyadenopathies as well as two skin ulcerations highly suggestive of trypanosomiasis. Microscopic examination of cutaneous and peripheral blood smears confirmed the diagnosis of haemolymphatic infection with T. b. gambiense with trypanosomal chancres. Examination of the cerebrospinal fluid was normal. The patient was successfully treated with pentamidine isethionate. CONCLUSIONS: Recognition of cutaneous manifestations may allow a rapid diagnosis of African trypanosomiasis that is essential for timely and efficient treatment and survival.

[Transverse radioulnar branch of the dorsal ulnar nerve: anatomic description and arthroscopic implications from 45 cadaveric dissections]. / Le rameau transverse de la branche dorsale du nerf ulnaire: anatomie et rapports avec les voies arthroscopiques du poignet: quarante-cinq dissections.

PURPOSE OF THE STUDY: We conducted an anatomic study of the transverse branch of the dorsal ulnar nerve to describe its morphology and position in relation to arthroscopic exploration portals. MATERIAL AND METHODS: Forty-five non-side-matched anatomic specimens of unknown age and gender were preserved in formol. The dorsal branch of the ulnar nerve was identified and dissected proximally to distally in order to reveal the different terminal branches. The morphometric analysis included measurement of the length and diameter of the transverse branch and measurement of wrist width. We also measured the smallest distance between the transverse branch and the ulnar styloid process, and between the branch and usual arthroscopic portals (4-5, 6R, 6U) in the axis of the forearm. RESULTS: The transverse branch was inconstant. It was found in 12 of the 45 dissection specimens (27%). In two-thirds of the specimens, the branch ran over less than 50% of the wrist width, tangentially to the radiocarpal joint. Mean nerve diameter was 1 mm. It was found 5-6 mm from the ulnar styloid process and was distal to it in 83% of the specimens. The dissections demonstrated two anatomic variants. Type A corresponded to a branch running distally to the ulnar styloid process, parallel to the joint line (10/12 specimens). Type B exhibited a trajectory proximal to the ulnar styloid process, crossing the ulnar head (2/12 specimens). The relations with the arthroscopic portals (4-5, 6R, 6U) showed that the mean distance from the branch to the portal was 3.75 mm for the 4-5 portal (distally in 11/12 specimens), 3.68 mm for the 6R portal (distally in 10/12 specimens), and 4.83 mm for the 6U portal (distally in 7 specimens and proximally in 5). DISCUSSION: To our knowledge, there has been only one report specifically devoted to this transverse branch. Two other reports simply mention its existence. According to the literature, the transverse branch of the dorsal ulnar nerve occurs in 60-80% of the cases. We found two anatomic variations different than those described in the literature. Based on our findings and data reported previously, we propose a new classification, describing two main types. In Type 1, the transverse branch arises proximally to the ulnar styloid process;type 1A and type IB are described in relation to the direction of the branch. In Type II, the branch arises distally to the ulnar styloid process;type IIA and type IIB again being described in relation to the direction of the branch. On the tangential trajectory over the radiocarpal joint, the morphometric data show a zone of risk described by a rectangle measuring 10 mm wide (6 mm distal and 4 mm proximal to the ulnar styloid process) and covering 50% of the wrist width. The relations with arthroscopic portals describe a zone of risk corresponding to a 5-7 mm radius circle centered on the portals (4-5, 6R, 6U), which includes 83% of the transverse branches.

Hypothyroid goitre in a ram: chemical analysis gives indirect evidence for a structurally altered type of ovine thyroglobulin.

The thyroglobulin of a ram of the East Friesian milk sheep breed suffering from goitre was investigated by physico- and immunochemical methods. The respective ram was the only animal amongst the other sheep of the flock, that exhibited severe goitre, additionally showing depressed behaviour. Results of the thyroid-stimulating hormone response test were indicative of hypothyroidism. The dysfunction of the thyroid gland could be treated by additional iodine supplementation quite successfully, although all sheep had been given iodinated cattle salt throughout the course of the history. Without reducing conditions sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) of isolated thyroglobulin molecules of the ram and control sheep did not reveal different band patterns, but under reducing conditions different band patterns were evident for the respective animals: the ram's thyroglobulin displayed two main bands, those of healthy reference sheep only one. Both bands reacted equally with anti-thyroglobulin antibodies, even with those produced by immunizing rabbits with single bands. The reduced single thyroglobulin band of healthy sheep corresponded to a truncated form of that molecule, whereas the additional main band of the ram was a more resistant, intact thyroglobulin subunit, as was shown by mass spectrometry. In conclusion, results of physico- and immunochemical investigations gave evidence of a modification of thyroglobulin with suspected different iodine binding properties in the ram. The latter finding may have clinical relevance in similar cases in other species, as it is an example of the impact that a minor change in a protein molecule may have on a complete metabolic pathway. Additionally, it could be shown, that in the ovine species the generally found single main band of thyroglobulin after reduction is a truncated form and not an intact subunit. This truncation seems to be induced in vitro by the reductive sample pretreatment prior to SDS-PAGE.

Repair of distal biceps tendon ruptures using a suture anchor and an anterior approach.

In a prospective study, eight consecutive patients with nine ruptures of the distal biceps tendon underwent repair through a single incision. All patients were satisfied with their clinical results and had full ranges of elbow and forearm motion. There were no radial nerve injuries and no radio-ulnar synostoses. Isokinetic testing, after correction for dominance, demonstrated a 6% strength deficit, but 7% higher endurance in the repaired extremity for the flexion-concentric test, and no strength deficit and 13% higher endurance for supination. The improved endurance is probably explained by initial reduced effort due to apprehension which minimized subsequent fatigue.

Influence of pressure upon coupling pressurized capillary electrochromatography with nuclear magnetic resonance spectroscopy.

In this work, the influence of supplementary pressure on the separation efficiency of pressurized capillary electrochromatography (pCEC) was examined. At low pressures of up to 30 bar, which is more than sufficient to prevent bubble formation, no significant loss in separation efficiency is observed. Even at 100 bar, the efficiency of pCEC is still significantly better than without application of an electric field. In addition, analysis times are drastically reduced compared to both capillary electrochromatography (CEC) and capillary HPLC. On the basis of these results, an improved interface for capillary NMR coupling is described and used for the separation and identification of a mixture of unsaturated fatty acid methyl esters. Under these conditions, the analysis time could be shortened by up to a factor of 10 when pCEC is coupled to NMR spectroscopy.

Concurrent weekly carboplatin and radiotherapy for nasopharyngeal carcinoma: report of a joint phase II study.

We report a phase I/II study of weekly concurrent carboplatin and radiotherapy in patients with nasopharyngeal carcinoma (M0 stage). Of 47 patients registered, 45 completed the treatment course. Twenty-six (55%) (95% CI, 41-69%) patients experienced > or =grade 3 acute toxicity (RTOG). Five (11%) (95% CI, 2-20%) patients experienced > or =grade 3 chronic toxicity. This regimen appears to have acceptable toxicity compared to the experimental arm of Phase III Intergroup Study 0099, but progression-free and overall survival are probably inferior. At present, there is no data to suggest that carboplatin can replace cisplatin for concurrent chemoradiation for NPC.

Relative weights of the human carpal bones: biological and functional interests.

The relative carpal weights (Weight of each of the eight carpal bones/Weight of the complete carpus x 100) were studied in a series of 95 complete human adult carpi (dried bones). The greatest was the capitatum (19.92%; mean rank 1.16) and the smallest the pisiform (4.43%; mean rank 8.00). The scaphoideum and the hamatum presented very near values (17.19 and 15.81%; mean ranks 2.34 and 2.74), as did the lunatum and trapezium (12.56 and 12.52%; mean ranks 4.41 and 4.48), and the triquetrum and trapezoideum (9.21 and 8.36%; mean ranks 6.19 and 6.68). Within the proximal row, a regular radio-ulnar decrease was observed from the scaphoideum (39.58%) to the pisiform (10.20%). Within the distal row, a marked break existed between the trapezoideum (14.77%) and the capitatum (35.19%); the capitato-hamatal element represented 63.11% of the distal row. The distal row (mean 56.61%) was always a little heavier than the proximal row (mean 43.39%), resulting in a mean proximo-distal weight ratio of 0.77. A radio-ulnar decrease in the relative weights was observed from the radial to the ulnar carpal columns. The determination of the relative carpal weights is simple, reproducible, non-invasive, rapid, and inexpensive, and can be considered an interesting and valuable approach to the estimation of the relative carpal volumes. Relative carpal weights reveal the intrinsic proportions of the carpus and are the reflection of biological, functional and evolutionary constraints. Interesting relations appear with carpal growth and ossification, with functional characteristics, and with evolutionary processes.

Microvascularisation of the raphe buccalis in edentulous subjects, fetus, new-born and adult.

The aim of this study is to describe the microvascularisation of the raphe buccalis located at the inner surface of the cheek. The raphe buccalis is the zone where the maxillary and mandibulary prominences fuse in the embryo during the second month of life. This study was conducted using heads from edentulous subjects, fetuses, newborns and adults, injected with Indian ink in agar, then dissected or sectioned in the three basic planes. The vascular networks of the raphe buccalis are as followed: a deep reticular network, a superficial reticular network and a papillary network. The microvascularisation of the raphe buccalis classifies it as a continuation of the commissure of the mouth and of the mucosa of the cheek.

Improved column preparation and performance in capillary electrochromatography.

Problems encountered in capillary electrochromatography, i.e. non-reproducible column manufacture, bubble formation during usage, short column lifetimes and limited choice of packing particles are addressed by the development of fritless or single-frit, internally tapered, segmented and dead-volume free coupled capillary columns. The Van Deemter plots measured demonstrate the performance of these high-quality capillaries which are suitable for capillary electrochromatography as well as for capillary high-performance liquid chromatographic applications.