Root Walker: an automated pipeline for large scale quantification of early root growth responses at high spatial and temporal resolution

Plants are sessile organisms that constantly adapt to their changing environment. The root is exposed to numerous environmental signals ranging from nutrients and water to microbial molecular patterns. These signals can trigger distinct responses including the rapid increase or decrease of root growth. Consequently, using root growth as a readout for signal perception can help decipher which external cues are perceived by roots, and how these signals are integrated. To date, studies measuring root growth responses using large numbers of roots have been limited by a lack of high-throughput image acquisition, poor scalability of analytical methods, or low spatiotemporal resolution. Here, we developed the Root Walker pipeline, which uses automated microscopes to acquire time-series images of many roots exposed to controlled treatments with high spatiotemporal resolution, in conjunction with fast and automated image analysis software. We demonstrate the power of Root Walker by quantifying root growth rate responses at different time and throughput scales upon treatment with natural auxin and two mitogen-associated protein kinase cascade inhibitors. We find a concentration-dependent root growth response to auxin and reveal the specificity of one MAPK inhibitor. We further demonstrate the ability of Root Walker to conduct genetic screens by performing a genome-wide association study on 260 accessions in under 2 weeks, revealing known and unknown root growth regulators. Root Walker promises to be a useful toolkit for the plant science community, allowing large-scale screening of root growth dynamics for a variety of purposes, including genetic screens for root sensing and root growth response mechanisms.

Mid-term results of ligament tenodesis in treatment of scapholunate dissociation: a retrospective study of 20 patients

The purpose of this retrospective study was to assess the modified Brunelli technique for the treatment of chronic irreparable complete scapholunate ligament rupture, causing a reducible carpal malalignment without secondary osteoarthritis. A total of 20 patients were treated using this technique. At a mean follow-up period of 24 months (range 6-53, SD 15), pain on a visual analogue scale had improved from 6 (range 3-10) to 3 (range 0-7). Function measured with the DASH score had improved from 37 (range 11-90) to 20 (range 0-53). Range of motion was reduced in flexion by a mean of 19° (range 10-45), and in extension by a mean of 14° (range 0-35). Mean grip strength at last follow-up was 81% of the uninjured hand (range 50-100%) Three patients developed scapholunate advanced collapse (stage II) requiring salvage surgery. Scapholunate ligament reconstruction with the modified Brunelli technique showed satisfactory results in this study. Extended studies are needed to determine the long-term benefits of this reconstructive procedure.

LEVEL OF EVIDENCE

IV.

Vascularized medial femoral condyle graft for management of scaphoid non-union

The purpose of this study was to assess the results of the management of difficult scaphoid non-unions using a vascularized medial femoral condyle graft. We operated on 30 patients with necrosis of the proximal pole or with severe humpback deformity or who presented with persistent non-union despite previous surgery. Twenty-four cases in our series showed full consolidation and six cases showed persistent non-union. The free vascularized medial femoral condyle bone graft can provide not only structural support, but also a consistent and good blood supply that results in excellent rates of union. Level of evidence: IV.

[Case report: acute carpal tunnel syndrome with prolapse of the median nerve]

We report a case of an 80-year-old woman with an acute carpal tunnel syndrome. This was based on an acute episode of chondrocalcinoses and accompagnied by a prolaps of the median nerve into a gap of the forearm fascia as result of a cut injury in childhood.

Remarks on boiling water reactor stability analysis – part 2: stability monitoring

In part 1 of this article we explained the partly relative complex solution manifold of the differential equations describing the stability behaviour of a BWR, in particular the coexistence of different types of solutions, such as the coexistence of unstable limit cycles and stable fixed points are of interest from the operational safety point of view. The part 2 is devoted to the surveillance of the stability behaviour. We summarize some stability monitoring methods and suggest to support stability tests by RAM-ROM analyses in order to reveal in advance the stability “landscape” of the BWR in a parameter region high sensitive for appearing of linear unstable states. The analysis of an especial stability test, performed at NPP Leibstadt (KKL), makes it clear that the measurement results can only be interpreted by application of bifurcation analysis.

Remarks on boiling water reactor stability analysis – part 1: theory and application of bifurcation analysis

Modern theoretical methods for analysing the stability behaviour of Boiling Water Reactors (BWRs) are relatively reliable. The analysis is performed by comprehensive validated system codes comprising 3D core models and one-dimensional thermal-hydraulic parallel channel models in the frequency (linearized models) or time domain. Nevertheless the spontaneous emergence of stable or unstable periodic orbits as solutions of the coupled nonlinear differential equations determining the stability properties of the coupled thermal-hydraulic and neutron kinetic (highly) nonlinear BWR system is a surprising phenomenon, and it is worth thinking about the mathematical background controlling such behaviour. In particular the coexistence of different types of solutions, such as the coexistence of unstable limit cycles and stable fixed points, are states of stability, not all nuclear engineers are familiar with. Hence the part I of this paper is devoted to the mathematical background of linear and nonlinear stability analysis and introduces a novel efficient approach to treat the nonlinear BWR stability behaviour with both system codes and so-called (advanced) reduced order models (ROMs). The efficiency of this approach, called the RAM-ROM method, will be demonstrated by some results of stability analyses for different power plants.

[Clinical presentation, diagnosis and treatment of the carpal tunnel syndrome]

The carpal tunnel syndrome is the most common of the compression syndromes. The leading symptom is the "falling asleep" of the radial-sided fingers. The diagnosis is confirmed by the neurological examination. In the early stage, conservative treatment is justified, but in the advanced stage surgical decompression (carpal tunnel release) involving splitting of the transverse carpal ligament is indicated. In the hands of an experienced hand surgeon the operation is a routine procedure with a low complication rate.

Der fortgeschrittene karpale Kollaps: Resektion der proximalen Handwurzelreihe (PRC) oder mediokarpale Teilarthrodese? Eine vergleichende Studie

Between July 2000 and February 2002, 26 wrists were treated because of SLAC, SNAC and radiocarpal arthrosis after fracture of the distal radius. In 14 cases proximal row carpectomy (PRC) and in twelve cases limited midcarpal arthrodesis (LWF) was performed. Follow-up was after a mean time of 16.8 (PRC) and 13.7 months (LWF) on ten wrists each. There was one complication in the PRC group and two in the LWF group. In all cases significant reduction of extension/flexion was observed with a mean range of motion of 69 degrees (PRC) and 71 degrees (LWF). The reduction of pain postoperatively was almost identical in both groups. Comparing grip-strength to the unoperated hand, we measured 26 compared to 39 kg in the PRC group and 28 compared to 46 kg in the LWF group, respectively. The DASH-score for the LWF group was 30 points and therefore better than the 36 points for the PRC group.

[Individual perforator flaps of the upper extremity]

Perforator flaps allow an individual flap design on the basis of a preoperative ultrasound examination. Aim of the present study is a preliminary evaluation of results and technical pitfalls of this new technique in the use for flap coverage on the dorsum of the hand and the elbow region. Since 1999, seven individually designed pedicled perforator flaps were prepared on the upper extremity. In four cases, defects on the dorsum of the hand and in a further three defects in the elbow region were treated. In the latter cases the flaps were harvested in a mainly epifascial plane, without dissecting the perforating vessels down to their origin. Five flaps were based on perforating vessels of the interosseous arteries, a further two from the lateral collateral humeral artery. Three out of four pedicled perforator flaps used on the dorsum of the hand healed completely. One flap was lost because of venous insufficiency due to the lack of wrist immobilisation. In the elbow region, two out of three defects were successfully covered with an individual perforator flap. One flap was lost due to venous insufficiency, a further needed an additional split-skin graft with a partial flap loss. The main advantage of the presented technique remains the possibility of individual flap design. However, the donor-site defect is almost negligible since in most cases a primary closure of the donor site was possible. The main arteries remained untouched leaving the blood supply to the hand unchanged. Nevertheless, the mainly epifascial harvest of the perforating vessels in the elbow region has the disadvantage of a short pedicle together with a high degree of torsion which leads to an increased risk of flap loss due to venous insufficiency.

[Perforator flap-plasty and applications to hand surgery]

In contrast to the classical fasciocutaneous and musculocutaneous flaps, perforator flaps are supplied only by a single perforating branch. The aim of this paper is to present the surgical technique and to discuss the use of perforator flaps in hand surgery. Our previous studies have demonstrated the reliability of a preoperative Doppler for planning perforator flaps in reconstructive surgery of the breast: With 286 preoperatively localized perforating branches, a total of 162 were confirmed in intraoperative dissection. In 37 out of these 46 perforator flaps (80%), a preoperatively localized perforating branch could be used. Based on these results, the individual design of perforator flaps harvested on the forearm for defects on the dorsum of the hand is possible. In a preoperative Doppler exam, a perforating branch, i.e. of the posterior interosseous artery, can be localized. The intraoperative confirmation of the perforating branch allows the successful defect coverage with a distally pedicled flap without taking fascia or septum. In our experience, this possibility of planning an individually designed perforator flap is the major advantage for applications of the perforator flap technique in hand surgery. This is especially true in cases where the harvest of a fasciocutaneous flap is unreliable or impossible due to anatomic variations. On the other hand, the dissection of the pedicle is technically demanding and the individual distribution of the perforating branches requires a high degree of flexibility. However, we do consider this new technique to be a further extension in the armamentarium for soft-tissue coverage of the hand.

[Treatment and outcome of complications after free flap-plasty]

Free tissue transplantation is a routine procedure in reconstructive surgery. Although a lot of free flap techniques have been described, the postoperative management of complications has gained only little interest. Nevertheless, complications of perfusion after free tissue transplantation are not rare and require a systematic approach. The aim of this study is to classify perfusion failures with a simple grading system prospectively on a large clinical series and to evaluate the results of treatment to improve management. In the past ten months, 70 consecutive free flaps have been performed. By the end of the operation, the operating surgeon gave a prognosis concerning the probability of a possible perfusion complication. Postoperative monitoring was done exclusively by clinical examination (colour, time for recapillarisation and bleeding after puncture). According to these parameters, arterial and venous insufficiencies have been classified into four grades. After recording type, time and treatment of a postoperative complication, the result of treatment was rated subjectively and a cause was noted when possible. The final result was classified either as total flap loss, partial flap loss or successful tissue transplantation. A total of 28 (40%) complications, which were treated with an average of 2.1 options, were recorded. The ratio between arterial and venous failure was 15:13. In 21 cases surgical intervention became necessary (intraoperative n = 12, postoperative n = 9). The arising complication was diagnosed correctly in nine cases by the operating surgeon. In ten cases, the cause of the complication remained unclear. In 18 cases, the complication was treated successfully without any flap loss. In six cases partial flap loss was observed and in four cases a total flap loss had to be accepted. Our results confirm that only few objective criteria for treatment options with perfusion failures after free tissue transplantation exist. Nevertheless, the presented classification is a useful tool for standardized evaluation of the results. The various salvage techniques result in positive outcomes for most of the patients.

[Pedicled versus free TRAM flap for breast reconstruction]

In breast reconstruction, the free TRAM-flap offers many advantages over the pedicled TRAM-flap. Due to its superior perfusion, the free flap rarely develops necrosis. Shaping of the flap is easier due to the lack of the thick muscle pedicle. Because the rectus muscle is spared, there is minimal donor site morbidity. However, the necessary microvascular anastomoses reduced the acceptance of the free TRAM-flap. During a 13-months period, 51 breast reconstructions were performed in 41 patients, 31 unilateral and ten bilateral. 45 flaps served for delayed reconstruction and six flaps for immediate reconstruction. The operations were performed by two teams working simultaneously. The average operating time was 3.9 hours for unilateral and 6.9 hours for bilateral delayed reconstruction. For immediate reconstruction, 6.2 and 6.3 hours were required for uni- and bilateral procedures, respectively. In 38 flaps, the thoracodorsal vessels served as recipient vessels; 13 flaps were anastomosed to the internal mammary artery and vein. Postoperative complications were observed in 13 patients. Three vessel anastomoses had to be revised. In one flap, a partial necrosis occurred; in two flaps hematoma evacuation was necessary. Two patients suffered from fat necroses at the abdomen and one umbilicus was lost. Skin irritations and seromas at the abdomen occurred in five patients. Pulmonary embolism was diagnosed in one patient three weeks postoperatively. Abdominal hernias or bulging in the epigastric area were not observed up to 15 months after reconstruction. These results reveal a low complication rate for breast reconstruction with the free TRAM-flap. The advantages of this technique as compared to the pedicled technique are discussed.

Impossible harvest of the posterior interosseous artery flap: a report of an individualised salvage procedure

Although the posterior interosseous artery flap represents a reliable technique to provide vascularised skin cover for the dorsum of the hand, the dissection of the flap is often very difficult because of anatomical variants. The weakest part of the vascularisation is the middle third of the posterior interosseous artery. Whenever it is discovered during the operation that such a flap is impossible to harvest, or likely to be unreliable, there is an immediate need to choose an alternative. Such a case is reported here. The individual anatomical situation allowed the dissection of a flap, the pedicle of which carried its blood supply from a perforating branch of the anterior interosseous artery. The technique described offers an individual solution to the problem of skin coverage when the harvest of the posterior interosseous artery is impossible.

[Plastic surgery in soft tissue reconstruction in large extremity defects]

Soft-tissue defects in the extremities vary greatly, depending on the trauma mechanism, localization and a number of factors related to the patient's physical condition. We offer an overview of the plastic surgery methods in reconstruction of different soft-tissue defects in the extremities, beginning with the diagnostic, clinical and radiological measures that make classification of soft-tissue defects possible, and then giving a concentrated view of the appropriate reconstruction methods. Collaboration between traumatology and plastic surgery seems to be especially important in lesions in the extremities.

[The scapula flap--overview and personal experiences]

Since the first report in the literature by Dos Santos in 1980, the scapula flap has become one of the most commonly used fascio-cutaneous free flaps. This is due to its numerous advantages and its few inconvenients. Because of the constant anatomy, the minor donor site defect and its good aesthetic result, the scapula flap replaced other more traditional flaps such as the radial forearm or the latissimus dorsi flap. Being a flap of the "subscapular artery system", it offers the possibility to be harvested "en bloc" with the other flaps of this system for complex reconstruction procedures. In our opinion, the scapula flap is the treatment of choice to treat cutaneous defects of the lower extremity which could not be covered by local flaps. In head-neck reconstruction, the colour and texture of the skin offered by this flap is superior to other free flaps. A thick, well visible horizontal scar in the donor site is the only real inconvenience of the scapula flap. It seems that the parascapula-flap (Nassif et al. 1982) which offers the same properties as the scapula flap is on the way to replace the scapula flap in the future. After a six-year experience with this flap we will present a current concept review and our own experience based on 30 cases. Moreover, we would like to report on some technical refinements.

Enhancement of host resistance against virus infections by MTP-PE, a synthetic lipophilic muramyl peptide--I. Increased survival in mice and guinea pigs after single drug administration prior to infection, and the effect of MTP-PE on interferon levels in sera and lungs

Muramyl tripeptide-phosphatidylethanolamine (MTP-PE, CGP 19835) displays prophylactic antiviral activity in mice infected with influenza viruses A and B, parainfluenza 1 virus or herpes simplex type 1 viruses (HSV/1) and in guinea pigs infected with herpes simplex type 2 viruses (HSV/2). MTP-PE is effective when given in a single intranasal dose as early as 1-4 weeks before infection. In the case of HSV/2 infections, prophylactic effectiveness can be demonstrated after a single topical application into the vagina seven days before infection. Antiviral effects are observed in response to doses as little as 0.001 mg/kg bodyweight. The activity of the substance seems to be inversely related to the size of the viral inoculum, but poor dose-effect relation is demonstrable in a dose-range extending over four to five orders of magnitude. Furthermore, the compound is devoid of antiviral effects in vitro. MTP-PE does not induce interferon (IFN) in serum and lung, nor does it influence kinetics or quantity of serum and lung IFN content in the course of viral infections. However, when given intranasally 7 days before an oral dose of tilorone, increased levels of IFN in lung suspensions are observed.

Effect of low-dose somatostatin infusion on pancreatic and gastric endocrine function in lean and obese nondiabetic human subjects

The present study was designed to compare, in lean and obese nondiabetic subjects, basal and postprandial levels of peripheral venous plasma insulin, glucagon, gastrin, pancreatic polypeptide (PP), glucose, triglycerides, and somatostatin-like immunoreactivity (SLI) during the infusion of synthetic somatostatin-14 or saline. Thirty-five minutes before the ingestion of the test meal, an infusion of synthetic somatostatin-14 was started at a rate of 0.5 ng/kg X min and was increased to 1.0 ng/kg X min 30 min after consumption of the meal and lasted for another 90 min. During the infusion of saline, basal peripheral vein levels of insulin, gastrin, and triglycerides were elevated in obese subjects, whereas basal plasma SLI levels were significantly lower compared with the lean controls. Basal glucagon and PP levels were similar in both groups. After the ingestion of the meal, augmented concentrations of insulin and gastrin were observed in the obese subjects, whereas postprandial SLI and PP levels were reduced. Chromatography of fasting plasma revealed all measurable SLI to be confined to the void volume fractions of a Bio-Gel P-10 column. The rise in SLI after the meal was due to an increase of SLI co-eluting with somatostatin-28 and somatostatin-14. During the infusion of somatostatin, only basal insulin levels were significantly lower in the obese subjects, whereas no change of any basal hormone level was observed in the lean group. During the infusion of somatostatin, SLI levels were elevated by 20-30 pg/ml in both groups compared with the saline controls. During the infusion rate of 0.5 ng/kg X min, only postprandial PP levels were reduced significantly in the obese group, while all the other parameters were unaffected in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)