Optogenetically stimulating intact rat corticospinal tract post-stroke restores motor control through regionalized functional circuit formation.

Current neuromodulatory strategies to enhance motor recovery after stroke often target large brain areas non-specifically and without sufficient understanding of their interaction with internal repair mechanisms. Here we developed a novel therapeutic approach by specifically activating corticospinal circuitry using optogenetics after large strokes in rats. Similar to a neuronal growth-promoting immunotherapy, optogenetic stimulation together with intense, scheduled rehabilitation leads to the restoration of lost movement patterns rather than induced compensatory actions, as revealed by a computer vision-based automatic behavior analysis. Optogenetically activated corticospinal neurons promote axonal sprouting from the intact to the denervated cervical hemi-cord. Conversely, optogenetically silencing subsets of corticospinal neurons in recovered animals, results in mistargeting of the restored grasping function, thus identifying the reestablishment of specific and anatomically localized cortical microcircuits. These results provide a conceptual framework to improve established clinical techniques such as transcranial magnetic or transcranial direct current stimulation in stroke patients.

Clinical results of flexor tendon repair in zone II using a six-strand double-loop technique compared with a two-strand technique.

The clinical and functional results of 46 patients who underwent zone II flexor tendon repair using the Lim/Tsai technique combined with the Kleinert/Duran early active mobilisation regime and place and hold exercises were assessed. The results were compared with 25 patients who were treated by the modified Kessler technique and the Kleinert/Duran regime alone. After a follow-up of 8 to 17 weeks, the Lim/Tsai group had a better grip strength and a significantly better total active motion of 141 degrees compared with 123 degrees . The rupture rates (Lim/Tsai: 1/51; Kessler: 3/26) and the extension deficits were not statistically different in the two groups. However, the complication rate was significantly lower and the average time of treatment was significantly shorter in the Lim/Tsai group. These results support the use of the Lim/Tsai six-strand repair technique in zone II flexor tendon injuries and early active mobilisation without rubber-band traction.

[Revision surgery after carpal tunnel release using a posterior interosseous artery island flap]. / Revisionschirurgie des karpaltunnelsyndroms - ergebnisse der behandlung mit der dorsalen vorderarmlappenplastik.

PURPOSE: The aim of this study is to evaluate the results of fasciocutaneous posterior interosseous artery island flaps in the treatment of recurrent or persistent carpal tunnel compression syndrome (CTS). PATIENTS AND METHODS: From 1997 to 2006, 14 patients (8 women, 6 men, ages ranging from 26 to 77 years with a mean age of 55.7 years) have been operated for recurrent or persistent CTS, or for a neuropathic pain syndrome. All patients were treated with a posterior interosseous island flap following neurolysis of the scarred median nerve. The patients were evaluated pre- and postoperatively using a pain visual analogue scale and the DASH score. Sensibility, motor dysfunction, pain and success of the treatment were classified as good, better or bad. RESULTS: Mean follow-up of the patients was 23.8 months (1.7 to 93.5 months). The pain evaluation showed a statistically significant improvement (p < 0.005) decreasing from a mean value of 6.7 to 1.5. The DASH score was also statistically significantly improved postoperatively (p < 0.005). The best results were observed in patients without extensive preliminary median nerve damage. The duration of symptoms before re-operation did not influence the outcome. Seven patients demonstrated good, five improved and two patients maintained poor results. The two patients with poor results suffered from extremely scarred and injured median nerves following previous carpal tunnel surgery. CONCLUSION: Protective coverage of the median nerve by use of a fasciocutaneous island flap after failure of carpal tunnel release provides a good gliding tissue cover and reduces the risk of adhesions between the nerve and the surrounding tissues after previous surgery. While this protection of the nerve can reduce painful symptoms it does not guarantee total pain relief in all patients. Pain relief and functional recovery strongly depend on the preexisting condition of the median nerve.

Anatomy of the proximal cutaneous perforator vessels of the gracilis muscle.

An anatomic study was performed to analyse the proximal perforator vessels of the gracilis musculocutaneous flap. Twenty-three cadaver legs preserved by the method of Thiel were carefully dissected 24h after the proximal vascular pedicle was injected with a red silicone mass. Nine additional cadaver legs were injected with ink, to visualise the skin area supplied by the proximal perforators, respectively, clarified by a modified Spalteholz technique to demonstrate the anatomic course of the perforators. A considerable variation in numbers and localisation of proximal cutaneous perforators was found. One to four perforators were seen within an area of 6 x 6 cm(2) at the entrance of the main pedicle into the proximal gracilis muscle. Their external diameter ranged from 0.5 to 1.0 mm. The ink-injections showed an oval shaped angiosome with a mean surface of 88 cm(2) at the level of the proximal gracilis pedicle. We conclude from this anatomic study, that a cutaneous flap based on the medial circumflex femoral gracilis perforators can be harvested by experienced hands bearing in mind the unpredictable perforator-anatomy.

Mycobacterium marinum: MR imaging and clinical course of a rare soft tissue infection.

Mycobacterium marinum is a rare cause of soft tissue infections. The imposing MR appearance of the soft tissue involvement is in contrast to the chronic painless clinical manifestation.

[How reliable is the posterior interosseous artery island flap? A review of 88 patients]. / Wie zuverlässig ist die distal gestielte A. interossea posterior-Lappenplastik? Eine retrospektive Analyse von 88 Patienten*

The distally-based, reverse posterior interosseous flap can be used to reconstruct soft-tissue defects in the region of the hand, provided there is an intact anastomotic network of the posterior and anterior interosseous system at the wrist. Between 1986 and 2000, 88 flap procedures were planned. Anatomical variations were recorded in 21 patients (24 %), in five of which the flap could not be harvested. In the remaining 16 patients, flap dissection was more difficult due to anatomical variations. There was a complication rate of 23 %, including haematoma, congestion, infection or technical errors, which resulted in flap necrosis of variable degrees in 11 patients (13 %). In case of haematoma, flap loss could be reduced by early revision surgery. There was no statistical correlation between anatomical variations and complications or flap loss. Secondary flap corrections, including defatting and remodelling, were commonly performed in due course. Knowing the limitations of the posterior interosseous flap, fasciocutaneous flaps are considered ideal to reconstruct soft-tissue defects or contractures of the thumb web and the dorsal hand because of good tissue matching. Fascial flaps are a good option for palmar defects or to wrap around neurolyzed nerves.

The evolutionary split of Pinaceae from other conifers: evidence from an intron loss and a multigene phylogeny.

The second intron in the mitochondrial gene nad1 was surveyed using PCR, DNA sequencing, or Southern hybridization in 323 species (313 genera, 212 families) of seed plants. The intron was absent in all 22 species (22 genera, 8 families) of non-Pinaceae conifers studied, in Welwitschia mirabilis, and in seven angiosperms. Whereas absence of the intron in seven angiosperms and Welwitschia is likely due to seven independent losses when evaluated against the recently published multigene phylogenies, the lack of the intron in all non-Pinaceae conifers can be best explained by a single loss. These data suggest that the non-Pinaceae conifers represent a monophyletic group. We also conducted a phylogenetic analysis of seed plants using a combined data set of the partial exon and intron sequences of nad1 generated from this study and published sequences of mitochondrial cox1 and small subunit (SSU) rDNA, chloroplast rbcL, and nuclear 18S rDNA. The results supported the split of conifers into two groups: Pinaceae and non-Pinaceae conifers. The Gnetales were sister to Pinaceae, in agreement with the conclusion from other recent molecular phylogenetic studies that refute the anthophyte hypothesis.

Molecular identification of fine roots of trees from the Alps: reliable and fast DNA extraction and PCR-RFLP analyses of plastid DNA.

Fine roots of trees are intensively used as indicators to assess soil alterations, e.g. those owing to atmospheric inputs of acidifying substances, but their identification to species with morphological criteria is difficult. In this study, we established molecular techniques in order to identify fine roots of the 30 most common tree species of the Alps. We developed a protocol for efficient isolation of DNA from fine roots with extraction of DNA in the presence of polyvinylpyrrolidone (PVP) and polyvinylpolypyrrolidone (PVPP). The trnL (UAA) intron of plastid DNA was used as a marker for fine root identification. We amplified and sequenced this intron with plant universal primers. The size of the sequences ranged from 444 to 672 bp. A synoptic key for species identification was designed on the basis of restriction fragment patterns predicted from sequence data. Using the restriction enzyme TaqI as key enzyme, and where necessary HinfI, RsaI and CfoI, 16 taxa, including Picea abies, Larix decidua, Abies alba, and Fagus sylvatica, the dominant tree species of the Alpine region could be identified by agarose gel electrophoresis of restriction fragments. Fourteen taxa could be identified to the genus level, among them Quercus, Salix and Populus species. In a field study, conducted in a 20 x 30 m plot of a mixed forest with five tree species, fine roots of 43 out of 46 samples were identified and their distributions were mapped. These results demonstrate the utility of our DNA extraction method and of the trnL intron for the identification of fine tree roots.

Species-specific detection of Lobaria pulmonaria (lichenized ascomycete) diaspores in litter samples trapped in snow cover.

The foliose lichen Lobaria pulmonaria has suffered a substantial decline in central and northern Europe during the twentieth century and is now considered to be critically endangered in many European lowland regions. Based on demographic studies, it has been proposed that under the present environmental conditions and forest management regimes, dispersal of diaspores and subsequent establishment of new thalli are insufficient to maintain the remnant small lowland populations. Chances of long-term survival may therefore be reduced. The data and analytical power of these demographic studies are limited. Since lichen diaspores show very few species-specific morphological characteristics, and are therefore almost indistinguishable, the accurate assessment of diaspore flux would be a fundamental first step in better understanding the life cycle of L. pulmonaria. Here we present a new molecular approach to investigate the dispersal of L. pulmonaria diaspores in its natural environment by specifically identifying small amounts of DNA in snow litter samples at varying distances from known sources. We used a species-specific polymerase chain reaction (PCR) primer pair to amplify the ribosomal internal transcribed spacer region (ITS rDNA) and a sensitive automated PCR product detection system using fluorescent labelled primers. We detected considerable amounts of naturally dispersed diaspores, deposited as far as 50 m away from the closest potential source. Diaspores were only found in the direction of the prevailing wind. Diaspore deposition varied from 1.2 diaspores per m(2) per day at 50 m distance from the source to 15 diaspores per m(2) per day at 1 m distance. The method described in this paper opens up perspectives for studies of population dynamics and dispersal ecology mainly in lichenized ascomycetes but also in other organisms with small, wind-dispersed diaspores.

Rigid internal fixation of basilar fractures of the proximal phalanges by cancellous bone grafting only.

Ten patients with 13 basilar metaphyseal impaction fractures of the proximal phalanges of the fingers were treated with "rigid internal fixation" by bone grafting alone. When retrospectively reviewed at a mean follow-up of 32 months, bone healing had occurred without any relevant secondary displacement of the fracture fragments. The final ranges of motion were good and return to work was quicker than expected.

Haplotype variation in a mitochondrial tandem repeat of Norway spruce (Picea abies) populations suggests a serious founder effect during postglacial re-colonization of the western Alps.

Populations from 13 elevational transects of Norway spruce [Picea abies (L.) Karst] across the Alpine range were sampled to elucidate the geographical pattern of genetic variation in relation to postglacial re-colonization and to study elevational effects on haplotypic diversity. We assessed fragment length variation in a tandem repeat region of the mitochondrial (mt) nad1 intron 2. This maternally inherited genetic marker is suited to infer migration as it is dispersed by seed only. A total of 10 haplotypes was found, most of which were due to repeat copy number variation. An analysis of molecular variance (amova) showed that overall population differentiation was high (F(ST)=0.41), and it revealed a significant differentiation between monomorphic western and moderately to highly variable eastern Alpine populations. This phylogeographic pattern may be explained by a founder effect during postglacial re-colonization. An early arriving haplotype, assumed to originate from a western Carpathian refugium, could expand into suitable habitats, reducing the chances for establishment of subsequently arriving haplotypes. On the other hand, the high variation in populations within an Italian transect of the south-eastern Alps may be the consequence of merging migration pathways from and close distance to putative glacial refugia, most likely those assumed in the Carpathian mountains and on the Balkan peninsula or possibly in the central plains of Italy. An effect of elevation on haplotypic diversity was not evident, though a low, but significant, partition of total genetic variation was attributed to among-population variation in one Italian transect. Various factors, such as vertical seed dispersal and forest management, may account for blurring an otherwise established pattern of genetic variation on a small geographical scale.

Chloroplast microsatellites and mitochondrial nad1 intron 2 sequences indicate congruent phylogenetic relationships among Swiss stone pine (Pinus cembra), Siberian stone pine (Pinus sibirica), and Siberian dwarf pine (Pinus pumila).

We studied the phylogenetic relationships among the three stone pine species, Pinus cembra, P. sibirica, and P. pumila, using chloroplast microsatellites and mitochondrial nad1 intron 2 sequences. The three chloroplast microsatellite loci combined into a total of 18 haplotypes. Fourteen haplotypes were detected in 15 populations of P. cembra and one population of P. sibirica, five of which were shared between the two species, and the two populations of P. pumila comprised four species-specific haplotypes. Mitochondrial intron sequences confirmed this grouping of species. Sequences of P. cembra and P. sibirica were identical, but P. pumila differed by several nucleotide substitutions and insertions/deletions. A repeat region found in the former two species showed no intraspecific variation. These results indicate a relatively recent evolutionary separation of P. cembra and P. sibirica, despite their currently disjunct distributions. The species-specific chloroplast and mitochondrial markers of P. sibirica and P. pumila should help to trace the hybridization in their overlapping distribution area and to identify fossil remains with respect to the still unresolved postglacial re-colonization history of these two species.

Tandem repeats in plant mitochondrial genomes: application to the analysis of population differentiation in the conifer Norway spruce.

Mitochondrial DNA, widely applied in studies of population differentiation in animals, is rarely used in plants because of its slow rate of sequence evolution and its complex genomic organization. We demonstrate the utility of two polymorphic mitochondrial tandem repeats located in the second intron of the nad1 gene of Norway spruce. Most of the size variants showed pronounced population differentiation and a distinct geographical distribution. A GenBank search revealed that mitochondrial tandem repeats occur in a broad range of plant species and may serve as a novel molecular marker for unravelling population processes in plants.

[Is panarthrodesis the gold standard in wrist joint surgery?]. / Ist die Panarthrodese der Goldstandard der Handgelenkchirurgie?

In order to determine the value of panarthrodesis, 109 cases have been reviewed. Relevant complications occurred in 36%, whereof 20 were serious entailing reoperations. The procedure was most rewarding in patients with inflammatory arthritis which were mostly painfree and regained full strength, whereas in cases following trauma and avascular necrosis of the lunate, only 56% were painfree, and only 6% achieved contralateral strength. In comparison with 52 cases which had undergone procedures preserving wrist motion, the results were not different with regard to pain relief and strength, whereas in the patients treated accordingly, a functional amount of wrist motion could be preserved.

Chronic post-traumatic radial instability of the metacarpophalangeal joint of the finger. Long-term results of ligament reconstruction.

Chronic painful post-traumatic instability of the radial collateral ligament complex of the metacarpophalangeal joint of a finger was treated by tendon graft reconstruction in 24 patients. Seventeen patients (20 joints) were available for a retrospective study at a mean follow-up time of 105 months. Eighty percent of the joints showed excellent or good results, with relief of pain, return of adequate stability, a near normal range of motion and absence of degenerative changes.

Prospective multicenter trial of a plate for dorsal fixation of distal radius fractures.

A new plate designed specifically to address complex wrist pathology was used for the internal fixation of 22 complex fractures of the distal radius in 22 patients in a prospective multicenter trial. The majority of fractures were group C2- and C3-type fractures according to the Comprehensive Classification of Fractures. No plate failures, loss of reduction, nonunions, or infections occurred. Within the average follow-up time of 14 months, the functional results (including an average motion of 76% and an average grip strength of 56% of the contralateral side) were comparable to those reported for similar fractures in previous investigations. Five patients had irritation of the tendons in the second dorsal compartment. This trial serves both as a verification of the safety and efficacy of this distal radius plate as well as a demonstration of its utility in the treatment of complex fractures of the distal radius.