Increasing the structural and compositional diversity of ion-track templated 1D nanostructures through multistep etching, plastic deformation, and deposition.

Ion-track etching represents a highly versatile way of introducing artificial pores with diameters down into the nm-regime into polymers, which offers considerable synthetic flexibility in template-assisted nanofabrication schemes. While the mechanistic foundations of ion-track technology are well understood, its potential for creating structurally and compositionally complex nano-architectures is far from being fully tapped. In this study, we showcase different strategies to expand the synthetic repertoire of ion-track membrane templating by creating several new 1D nanostructures, namely metal nanotubes of elliptical cross-section, funnel-shaped nanotubes optionally overcoated with titania or nickel nanospike layers, and concentrical as well as stacked metal nanotube-nanowire heterostructures. These nano-architectures are obtained solely by applying different wet-chemical deposition methods (electroless plating, electrodeposition, and chemical bath deposition) to ion-track etched polycarbonate templates, whose pore geometry is modified through plastic deformation, consecutive etching steps under differing conditions, and etching steps intermitted by spatially confined deposition, providing new motifs for nanoscale replication.

FIB based fabrication of an operative Pt/HfO2/TiN device for resistive switching inside a transmission electron microscope.

Recent advances in microelectromechanical systems (MEMS) based chips for in situ transmission electron microscopy are opening exciting new avenues in nanoscale research. The capability to perform current-voltage measurements while simultaneously analyzing the corresponding structural, chemical or even electronic structure changes during device operation would be a major breakthrough in the field of nanoelectronics. In this work we demonstrate for the first time how to electrically contact and operate a lamella cut from a resistive random access memory (RRAM) device based on a Pt/HfO2/TiN metal-insulator-metal (MIM) structure. The device was fabricated using a focused ion beam (FIB) instrument and an in situ lift-out system. The electrical switching characteristics of the electron-transparent lamella were comparable to a conventional reference device. The lamella structure was initially found to be in a low resistance state and could be reset progressively to higher resistance states by increasing the positive bias applied to the Pt anode. This could be followed up with unipolar set/reset operations where the current compliance during set was limited to 400 µA. FIB structures allowing to operate and at the same time characterize electronic devices will be an important tool to improve RRAM device performance based on a microstructural understanding of the switching mechanism.

[Spine surgery in a combat support hospital]. / Wirbelsäulenchirurgie unter den Bedingungen eines militärischen Auslandseinsatzes.

BACKGROUND AND AIM: From July 2007 to October 2014, neurosurgical services have been continuously available in a multinational Role 3 combat support hospital in Mazar-e-Sharif (MeS), Afghanistan. In this paper, we analyze a 7-year operative and outpatient spinal surgery caseload experience. MATERIALS AND METHODS: The overall annual and monthly caseloads were determined. Additionally, the surgical cases were differentiated relating to the strength of the indication, the location of the surgical site, and the origin of the patients. The outpatient caseload and spectrum of the years 2012 and 2013 were also analyzed. RESULTS: A total of 341 surgeries were performed and 188 of them were spinal surgeries (55.1 %). The vast majority of surgeries were performed for degenerative diseases (127/188; 67.6 %). The proportion of fractures and penetrating injuries (61/188; 32.4%) increased over the observation period. Eighty percent of the immediate and urgent surgeries (within 12 h; n = 70) were performed for these indications. 19.8 % of the surgeries were done as an emergency, whereas 17.3 % had delayed urgency, and 62.9 % were elective procedures. Of the 1026 outpatient consultations documented, 82 % of them were related to spinal diseases. CONCLUSIONS: The overall caseload in addition to the distribution of location, strength of indication, and patient origin for MeS are significantly lower than that reported by other International Security Assistance Force (ISAF) nations in eastern and southern Afghanistan. In addition, the rate of elective surgeries and those carried out in civilian Afghan patients is highest in MeS. In comparison with MeS, none of the other ISAF military hospitals shows such a strong concentration of degenerative spinal conditions in their surgical spectrum. Nevertheless, the changing pattern of spine-related diagnoses and surgical therapies in the current conflict represents a challenge for future educational and material planning in comparable missions.

Percutaneous vertebral augmentation with polyethylene mesh and allograft bone for traumatic thoracolumbar fractures.

Purpose. In cases of traumatic thoracolumbar fractures, percutaneous vertebral augmentation can be used in addition to posterior stabilisation. The use of an augmentation technique with a bone-filled polyethylene mesh as a stand-alone treatment for traumatic vertebral fractures has not yet been investigated. Methods. In this retrospective study, 17 patients with acute type A3.1 fractures of the thoracic or lumbar spine underwent stand-alone augmentation with mesh and allograft bone and were followed up for one year using pain scales and sagittal endplate angles. Results. From before surgery to 12 months after surgery, pain and physical function improved significantly, as indicated by an improvement in the median VAS score and in the median pain and work scale scores. From before to immediately after surgery, all patients showed a significant improvement in mean mono- and bisegmental kyphoses. During the one-year period, there was a significant loss of correction. Conclusions. Based on this data a stand-alone approach with vertebral augmentation with polyethylene mesh and allograft bone is not a suitable therapy option for incomplete burst fractures for a young patient collective.

[Near-infrared spectroscopy for the detection of traumatic intracranial hemorrhage: Feasibility study in a German army field hospital in Afghanistan]. / Nahinfrarotspektroskopie zur Detektion intrakranieller traumatischer Hirnblutungen: Praktikabilitätsstudie in einem Bundeswehrrettungszentrum in Afghanistan.

Traumatic brain injury (TBI) is one of the most common causes of death in ordinary accidents, natural disasters, or warfare. The gold standard for diagnosis of TBI is the CT scan; a delay of diagnostics or medical care is the strongest independent predictor of mortality of TBI patients--particularly in the case of a surgically treatable intracranial hematoma. The proper classification of these patients is of major importance in situations where a CT is not accessible. A portable screening device that uses near-infrared spectroscopy (NIRS) technology allows a preliminary estimate of an intracranial hematoma. This study assessing practicability shows that the use of the device in a military medical rescue center (Kunduz, Afghanistan) is easy to learn and can be repeatedly used even under emergency room conditions. The technique can be applied in penetrating and blunt TBIs in the absence of an immediately available CT scan in rural areas, preclinically, under mass casualty conditions (e.g., in disaster situations) as well as in humanitarian crises or war zones. Nevertheless, further studies to assess the validity of this device are necessary.

Early postoperative results after removal of cranially migrated lumbar disc prolapse: retrospective comparison of three different surgical strategies.

Background. To compare the early postoperative results of three surgical approaches to lumbar disc herniations that migrated cranially. Minimally invasive techniques such as the translaminar and endoscopic transforaminal approaches are utilized in patients with lumbar disc herniations to gain access to cranially located disc material and to avoid the potentially destabilizing resection of ligament and bone tissue, which is associated with an extended interlaminar approach. Methods. This retrospective study compares the postoperative pain and functional capacity levels of 69 patients who underwent an interlaminar (Group A, n = 27), a translaminar (Group B, n = 22), or an endoscopic transforaminal procedure (Group C, n = 20). Results. Median VAS scores for leg pain decreased significantly from before to after surgery in all groups. Surgical revisions were required in thirteen cases (five in Group A, one in Group B, and seven in Group C; P = 0.031). After six weeks, there were significant differences in back pain and functional outcome scores and in the results for the MacNab criteria but not in leg pain scores. Conclusions. The interlaminar and translaminar techniques were the safest and fastest ways of gaining access to cranially migrated disc material and the most effective approaches over a period of six weeks.

[Selective dorsal decompression of degenerative cervical canal stenosis]. / Selektive dorsale Dekompression der degenerativen Zervikalstenose.

BACKGROUND: Hypertrophy of the dorsal ligaments is one reason for central stenosis of the cervical spinal canal. Selective decompression techniques without stabilization and fusion could be a sufficient alternative surgical treatment option. MATERIAL AND METHODS: This article presents the results of an observational study on 17 patients after treatment with selective decompression and undercutting of the cervical laminae and medial joint portion. The Japanese Orthopedic Association (JOA) score, the neck pain disability index (NPDI) and arm and neck pain on a visual analogue scale (VAS) were compared preoperatively and postoperatively (mean follow-up period was 14 months, minimum 12 months). The reduction of the stenosis and degree of adjacent level disease were measured using presurgical and postsurgical magnetic resonance imaging (MRI). The segmental and regional lordosis and range of motion were determined using the Cobb method on plain standing lateral radiographs. RESULTS: There were no complications and no revision surgery was necessary. All clinical parameters improved significantly. The stenosis was significantly decompressed and no progression of myelopathy was observed on MRI. The sagittal parameters and degree of adjacent level degeneration remained unchanged. CONCLUSION: The clinical and radiological results of this non-fusion technique are convincing. Selective decompression is therefore an alternative to laminectomy and fusion as well as laminoplasty.

[Percutaneous CT-guided destruction versus microsurgical resection of lumbar juxtafacet cysts]. / Perkutane CT-gesteuerte Destruktion vs. mikrochirurgische Resektion lumbaler Juxtafacettzysten.

BACKGROUND: Microsurgical resection is the standard treatment of lumbar juxtafacet cysts. Percutaneous computed tomography (CT) guided destruction of the cyst could be an alternative modality for inoperable patients. Comparative prospective studies for both treatment strategies do not exist. MATERIALS AND METHODS: This study involved a non-randomized, prospective trial on 45 patients suffering from sciatica or claudication caused by lumbar juxtafacet cysts. Of the patients 25 were operated on microsurgically and 20 patients were primarily treated using percutaneous CT-guided cyst destruction. RESULTS: The treatment in both groups was performed without complications in all patients. All patients treated microsurgically were pain-free (mean postoperative interval 27 months) but only 8 out of 20 patients treated percutaneously recovered completely (mean post-treatment interval 24 months). The remaining 12 out of 20 patients showed no relevant improvement and were operated on microsurgically. CONCLUSION: Minimally invasive cyst destruction is not a viable alternative to microsurgical resection considering the long-term outcome, neither in this study nor in the reviewed literature.

Surgery without assistance in newborns and infants with hydrocephalus and neural tube defects.

Standard neurosurgical procedures for hydrocephalus and open neural tube defects in newborns and infants under 6 months of age were performed by a single neurosurgeon on his own without the help of an assistant or scrub nurse. The objective of this study was to assess the outcome of these procedures in terms of operating time, the presence of bacterial infection, and wound healing. Between 2001 and 2004, a total of 126 procedures were performed on 82 patients under 6 months of age. We observed 1 bacterial and 2 fungal infections. Two infections had already been detected at the beginning of the surgical procedure in cerebrospinal fluid (CSF) specimens obtained from children with Candida ventriculitis. The other infection occurred after leakage of CSF from a myelomeningocele 10 days after initial surgery. Our study suggests that excellent results can be achieved in standard neurosurgical procedures without assistance even in high-risk newborns and infants if resource or other constraints require such an unconventional approach.

[Malignant fibrous histiocytoma. Clinical meaning of a rare entity]. / Das maligne fibröse Histiozytom der Mamma: Klinische Bedeutung einer seltenen Diagnose.

Less than 1% of primary malignant breast tumours are sarcomas. Malignant fibrous histiocytoma (MFH) are rare among them. Prospective randomized studies are impossible because of the rarity of cases. There is an increase of reported cases of sarcoma of the breast after organ-conserving therapies of breast carcinoma and postoperative irradiation. Even if MFH of the breast is very rare, the incidence rate is likely to increase with the rise of organ-conserving therapy of breast carcinoma. Therefore, efforts to optimize the therapy are justified. MFH should be included in the differential diagnosis in cases of large tumour diameters, rapidly progressive tumour growth and absence of axillary lymph nodes or distant metastasis. The report deals with a 90-year-old patient with exulcerated MFH of the left breast. It is not known whether she had any prior radiotherapy.

[Chronic subdural hematoma in patients under 35 years of age]. / Chronisches subdurales Hämatom bei Patienten unter 35 Jahren.

OBJECTIVE: Although chronic subdural haematoma (CSDH) is considered a condition of the elderly, it may also occur in younger patients. The objective of this study was to identify the cause of CSDH in younger patients. METHOD: In a group of 100 consecutive patients with CSDH diagnosed in our hospital between 1 January 2000 and 31 August 2003, we found nine patients to be younger than 35. These nine were assessed to identify their cause of CSDH. RESULTS: We found a predisposing cause in five of nine patients, three having a disorder of CSF balance, and two having a clotting disorder. Trauma was reported in only two of these five patients. Among the four patients without a predisposing factor a trauma was reported in three of them. In only one patient the cause of CSDH remained unknown. All patients made a complete recovery. CONCLUSION: Chronic subdural haematoma did also occur in younger patients. Trauma, CSF imbalance, and deranged clotting increase the risk of CSDH, however this disorder can also occur in the absence of identifiable predisposing factors or trauma.

[Spinal epidural empyema. Limited surgical treatment combined with continuous irrigation and drainage]. / Spinales epidurales Empyem. Limitierte operative Behandlung kombiniert mit kontinuierlicher Spüldrainage.

Epidural empyema of the spinal column is a rare, but in some cases devastating, disease. Surgery can be excessive or very limited. We want to report our results of combined therapy of limited surgical treatment and continuous irrigation with antibiotic solution and drainage. In the last 5 years we have operated on 12 patients (7 female, 5 male, median age: 61.5 years, range: 22-89 years) with spinal epidural empyema. All surviving patients were evaluated after 3 months including MRI. Six infections were caused by injections, two by spontaneous discitis, two by chronic systemic infections, and in two patients the cause remained unknown. In every case we implanted two catheters, one for irrigation with antibiotic solution and one for drainage. On average the catheters were used for 3 days. For evacuation in seven patients interlaminar fenestration in one, two, or three levels was enough. Only in one patient was a laminectomy performed. Five patients recovered totally, three partially, one did not recover at all, and three died. The autopsy of two dead patients showed complete healing of the operated area; they died because of lethal infections in other parts of their body. In only one case did a reoperation have to be done. The cause was an additional subdural empyema. In spite of the limited surgical procedure without relevant operative morbidity the reported method is an effective and safe therapy.

[Intraoperative three-dimensional imaging to monitor selective decompression in lumbar spinal stenosis]. / Intraoperative 3D-Bildgebung zur Kontrolle der selektiven Dekompression bei lumbaler Wirbelkanalstenose.

BACKGROUND: We are looking for a possibility to examine the amount of decompression in operations for spinal stenosis with an Iso-C(3D) fluoroscope (Siemens). METHODS: In ten patients operated on because of spinal stenosis from one side with undercutting, we performed a scan with the Iso-C(3D) fluoroscope during the operation. In five patients we additionally performed intraoperative myelography. RESULTS: In all cases we were able to make useful scans. Two times we changed our surgical procedure because of the scans. There were no complications because of the investigation with the Iso-C(3D) fluoroscope and none related to the myelography, but the myelography was dispensable. CONCLUSIONS: It is possible and useful to investigate the decompression in spinal stenosis intraoperatively with less effort.

Comparative distribution of sulphur, thiols and disulphides in the porcine stratum corneum.

Biochemical, histochemical and cytochemical analyses were used to determine the sulphur contents and the thiol and disulphide distribution in the stratum corneum (SC) of the wild boar (WB), a large domestic pig breed (DP) and the Goettingen miniature pig (GMP). The sulphur contents (% DW) were different in the three animal types (WB: 1.70-1.38 body, 0.54 ear; DP: 0.84-0.53 body, 0.50 ear; GMP: 2.28-2.51 body, 2.66 ear). The results of the histochemical analysis of SH- and -S-S- groups were clear, and densitometrical extinctions were highest in most body regions of the GMP for thiols and disulphides, followed by the DP for thiols, and the WB for disulphides. Absolute SC thickness was highest in the body of the GMP (62-80 mum), and generally lowest in the ear (20-38 mum) of all animal types. Relative SC thickness was the same for all animals in the body (40-66%), but lower in the ear (30%). Only -S-S- concentrations were correlated with SC thickness, and primarily in the GMP. Cytochemical analysis showed that high sulphur concentrations were obvious particularly in the CCE of corneal cells in the DP, as compared to the cytoplasm. Intracellular sulphur distribution was homogenous in the WB, and in the GMP, although in the latter at a higher concentration level. The results indicate breed-related effects on keratinisation in porcine corneal cells. Only the SC of the outer side of the ear of DP females is recommended as a model for humans.

Stromal antigen targeting by a humanised monoclonal antibody: an early phase II trial of sibrotuzumab in patients with metastatic colorectal cancer.

BACKGROUND: A novel immunological approach to colon cancer therapy is the antibody targeting of the fibroblast activation protein (FAP), which is highly expressed by stroma cells of this tumour. Unconjugated sibrotuzumab (BIBH 1), which is a humanised version of the murine anti-FAP mAb F19, was investigated for its anti-tumour activity, safety and pharmacokinetics. PATIENTS AND METHODS: Patients with metastatic colorectal cancer received weekly intravenous infusions of unconjugated sibrotuzumab at a dose of 100 mg over 12 scheduled weeks. The study was implemented as an open-label, uncontrolled, multicentre trial. RESULTS: 25 patients were enrolled. Patients had one or more measurable lesions, predominantly liver lesions, at baseline. At least 8 repeated weekly infusions of sibrotuzumab in 17 evaluable patients did not result in complete or partial remission. Rather, ongoing tumour progression was noted in all patients except for 2 patients with stable disease. However, progressive disease was also observed post-study in these 2 patients who received 1 and 6 additional infusions, respectively, of sibrotuzumab. Sibrotuzumab exhibited 2-compartment pharmacokinetics with a dominant terminal phase and t1/2 beta = 5.3 +/- 2.3 days. Adverse drug reactions (rigors/chills, nausea, flushing and one incidence of bronchospasm) were observed in 5 patients. Of the 24 patients given 2 or more infusions of sibrotuzumab, antibodies against sibrotuzumab were found in 3 patients (12.5%) after 4-12 infusions. CONCLUSIONS: Sibrotuzumab was well tolerated and safe. The minimal requirement for the continuation of this exploratory trial, of at least one complete or partial remission, or equivalently, of 4 patients with stable disease, was not met.

Congenital neuroblastoma mimicking early onset sepsis.

UNLABELLED: A newborn girl presented with symptoms of severe early onset sepsis but also with systemic hypertension (SH) at age 3 h. Plasma catecholamine (CAT) levels were extremely elevated, reflecting increased release of CAT from a congenital neuroblastoma (NB). Clinical symptoms at time of admission were: prolonged capillary refill (5 s), tachycardia, tachydyspnoea, metabolic acidosis (pH 7.17, lactate 11.8 mmol/l), fever (38.4 degrees C) and SH: 90/50/65 mmHg (systolic/diastolic/mean). The infant experienced organ failure (lung, heart, liver). A retroperitoneal dumbbell tumour was detected. Plasma CAT levels at age 15 h were: noradrenaline 219 nmol/l; adrenaline 13 nmol/l; and dopamine 65.3 nmol/l. SH responded to intermittent alpha-adrenergic blockage. CAT-related symptoms ceased within 1 week. The intraspinal NB was surgically removed when cord compression became symptomatic. The neurological and developmental state is normal at age 17 months. The abdominal NB regressed spontaneously. CONCLUSION: A neuroblastoma should be considered in newborn infants presenting with a shock-like condition together with systemic hypertension.

Analytical electron microscopical investigations on the apoplastic pathways of lanthanum transport in barley roots.

In transmission electron microscopy studies, lanthanum ions have been used as electron-opaque tracers to delineate the apoplastic pathways for ion transport in barley (Hordeum vulgare L.) roots. To localize La3+ on the subcellular level, e.g. in cell walls and on the surface of membranes, electron-energy-loss spectroscopy and electron-spectroscopic imaging were used. Seminal and nodal roots were exposed for 30 min to 1 mM LaCl3 and 10 mM LaCl3, respectively. In seminal roots, possessing no exodermis, La3+ diffusion through the apoplast was stopped by the Casparian bands of the endodermis. In nodal roots with an exodermis, however, La3+ diffusion through the cortical apoplast had already stopped at the tight junctions of the exodermal cell walls resembling the Casparian bands of the endodermis. Therefore, we conclude that in some specialized roots such as the nodal roots of barley, the physiological role of the endodermis is largely performed by the exodermis.

Epidural blood patch under fluoroscopic control: non-surgical treatment of lumbar cerebrospinal fluid fistula following implantation of an intrathecal pump system.

The treatment of lumbar cerebrospinal fluid fistula in the presence of an intrathecal catheter is known to be difficult. Open revision surgery is recommended in the literature, although the rate of recurrence is high. The epidural blood patch technique is well established as a successful treatment for post-dural-puncture headaches. Recent work about the distribution of the injected blood and theoretical considerations about the mechanism of action make this method suitable for the occlusion of spinal leakage even in the presence of an intrathecal catheter. In this note technical details are given for a successful therapy of lumbar cerebrospinal fluid fistula including the right positioning of the opening of the needle (cerebrospinal fluid can be expected intrathecally and epidurally) by injection of contrast medium first for myelography then for epidurography. In this procedure the (epidural) distribution of autologous blood can be indirectly controlled by compression of the dural sac. The method is easy to perform, and the possible risks are small.

Lumbosacral extradural arachnoid cysts: diagnostic and indication for surgery.

No critical discussion of the indication for the surgical treatment of lumbosacral extradural arachnoid cysts is found in the literature. Therefore, we want to compare the results in patients with operative and conservative treatment to define standards for a good surgical result. Over a period of 9 years, we operated on eight patients with a lumbosacral extradural arachnoid cyst and treated eight others conservatively. Only three of the operated patients experienced a postoperative relief of pain, but none was symptom free. The only one with continuing success had a preoperative history of 1 year only. MRI scans without contrast agent were misinterpreted in one included and one excluded case. The results of conservative treatment were nearly the same as those of operative treatment. MRI is the best diagnostic tool, but a variety of sequences must be used. Patients with a short pain history and a clear neurological deficit profited most from surgery. Patients with slight and not clearly related uncharacteristic symptoms should be excluded from surgery.

[Chondroma of the petrous bone. A contribution to differential skull base tumor diagnosis]. / Chondrom im Bereich des Felsenbeines. Ein Beitrag zur Differentialdiagnose der Schädelbasistumoren.

INTRODUCTION: Cartilaginous tumors of the mid-face and the skull base are rare. CASE REPORT: For the first time, a case report of a chondroma of the base of the ear in a 56-year-old woman is presented. In 1974 the patient developed a facial nerve paralysis while she was pregnant. Twenty-two years later the patient developed persistent headache and CT studies of the head were obtained, which showed an extensive tumorous lesion located at the base of the ear. A tumor was resected through an otoneurosurgical approach. The histological examination showed a chondroma. CONCLUSIONS: Even the rare diagnosis of a chondroma should be considered for a differential diagnosis of skull base tumors.