Pullout strength of anterior spinal instrumentation: a product comparison of seven screws in calf vertebral bodies

A lot of new implant devices for spine surgery are coming onto the market, in which vertebral screws play a fundamental role. The new screws developed for surgery of spine deformities have to be compared to established systems. A biomechanical in vitro study was designed to assess the bone–screw interface fixation strength of seven different screws used for correction of scoliosis in spine surgery. The objectives of the current study were twofold: (1) to evaluate the initial strength at the bone–screw interface of newly developed vertebral screws (Universal Spine System II) compared to established systems (product comparison) and (2) to evaluate the influence of screw design, screw diameter, screw length and bone mineral density on pullout strength. Fifty-six calf vertebral bodies were instrumented with seven different screws (USS II anterior 8.0 mm, USS II posterior 6.2 mm, KASS 6.25 mm, USS II anterior 6.2 mm, USS II posterior 5.2 mm, USS 6.0 mm, USS 5.0 mm). Bone mineral density (BMD) was determined by quantitative computed tomography (QCT). Failure in axial pullout was tested using a displacement-controlled universal test machine. USS II anterior 8.0 mm showed higher pullout strength than all other screws. The difference constituted a tendency (P = 0.108) when compared to USS II posterior 6.2 mm (+19%) and was significant in comparison to the other screws (+30 to +55%, P < 0.002). USS II posterior 6.2 mm showed significantly higher pullout strength than USS 5.0 mm (+30%, P = 0.014). The other screws did not differ significantly in pullout strength. Pullout strength correlated significantly with BMD (P = 0.0015) and vertebral body width/screw length (P < 0.001). The newly developed screws for spine surgery (USS II) show higher pullout strength when compared to established systems. Screw design had no significant influence on pullout force in vertebral body screws, but outer diameter of the screw, screw length and BMD are good predictors of pullout resistance.     

Pelvic Ring Fractures: Utility of Clinical Examination in Patients with Impaired Consciousness or Tracheal Intubation

Abstract Objective: To define the diagnostic accuracy of clinical examination in patients with impaired consciousness or endotracheal intubation to detect pelvic ring fractures and to identify those with severe bleeding. Methods: Included in this prospective data collection with retrolective data analysis were a consecutive series of blunt trauma victims with either a Glasgow Coma Scale ≤ 13 or tracheal intubation. Clinical examination comprised testing for stability of the iliac wings. Results: From 784 subjects (injury severity score 23.3 ± 17.4) 93 patients (11.9%) were found to have a pelvic ring fracture. Clinical instability of the pelvic ring was found in 42 patients. There was only one false positive. Fifty-two fractures could not be identified by clinical examination, including nine fractures (17%) that required surgical fracture stabilization (sensitivity of clinical examination 44.1%). Seventeen fractures (18.3%) were associated with a blood loss larger than 20% of circulating blood volume. Sixteen of those were identified by clinical instability of the pelvic ring (sensitivity 94.1%, specificity 97.0%, positive predictive value 38.1%, negative predictive value 99.9%). Conclusions: Clinical examination for stability of the pelvis in this selected group of patients missed a significant number of pelvic ring fractures including fractures that require surgical stabilization. The finding of a clinically unstable identifies most of the patients with the pelvic ring fracture being a major source of bleeding. A stable pelvis makes pelvic ring fracture as being the source of bleeding quite unlikely.     

Cognitive impairment in patients with chronic hepatitis treated with interferon alpha (IFNalpha): results from a prospective study.

BACKGROUND: Treatment with low-dose interferon alpha (IFN-alpha) is often associated with neuropsychiatric side effects. In addition to depression and anxiety, IFN-alpha associated cognitive impairment significantly affects patient's mental health and quality of life. AIMS OF THE STUDY: To measure possible effects of low-dose IFN-alpha on cognitive functioning and its relationship to the development of depression and anxiety. METHOD: We prospectively followed 38 patients with a chronic hepatitis B or C by neuropsychological tests and psychiatric self-rating scales during 12 weeks of low-dose treatment with IFN-alpha. RESULTS: Before IFN-alpha treatment, neuropsychological tests as well as self-ratings in the Beck's Depression Inventory (BDI), the Hospital Anxiety and Depression Scale (HADS) and the Self-Report Symptom Inventory 90 Items-Revised (SCL-90-R) were within the normal range. Following 12 weeks of treatment with IFN-alpha resulted in a slight, but significant increase in depression scores. Neuropsychological assessment after 12 weeks of IFN-alpha treatment showed a significant decrease of the immediate recall in the Auditory-Verbal Learning Test (AVLT) and a significant reduction of words recited in the Controlled Oral Word Association Test (COWA). Cognitive impairment did not significantly correlate with depressive symptoms or anxiety. CONCLUSION: Our results indicate that even low-dose IFN-alpha induces cognitive impairment independent from depressive symptoms, which might be related to functional disturbances in the prefrontal cortex and the hippocampus. We suggest close monitoring of cognitive function during IFN-alpha treatment of chronic hepatitis.     

Comparative analysis of neurotrophin receptors and ligands in vertebrate neurons: tools for evolutionary stability or changes in neural circuits?

To better understand the role of multiple neurotrophin ligands and their receptors in vertebrate brain evolution, we examined the distribution of trk neurotrophin receptors in representatives of several vertebrate classes. Trk receptors are largely expressed in homologous neuronal populations among different species/classes of vertebrates. In many neurons, trkB and trkC receptors are co-expressed. TrkB and trkC receptors are primarily found in neurons with more restricted, specialized dendritic and axonal fields that are thought to be involved in discriminative or 'analytical' functions. The neurotrophin receptor trkA is expressed predominantly in neurons with larger, overlapping dendritic fields with more heterogeneous connections ('integrative' or 'modulatory' systems) such as nociceptive and sympathetic autonomic nervous system, locus coeruleus and cholinergic basal forebrain. Surveys of trk receptor expression and function in the peripheral nervous system of different vertebrate classes reveal trends ranging from dependency on a single neurotrophin to a more complex dependency on increasing numbers of neurotrophins and their receptors, for example, in taste and inner ear innervation. Gene deletion studies in mice provide evidence for a complex regulation of neuronal survival of sensory ganglion cells by different neurotrophins. Although expression of neurotrophins and their receptors is predominantly conserved in most circuits, increasing diversity of neurotrophin ligands and their receptors and a more complex dependency of neurons on neurotrophins might have facilitated the formation of at least some new neuronal entities.     

Atypical presentation of distal renal tubular acidosis in two siblings

Primary distal renal tubular acidosis (dRTA) is an inherited disease characterized by the inability of the distal tubule to lower urine pH <5.50 during systemic acidosis. We report two male siblings who presented with severe hyperchloremic metabolic acidosis, high urinary pH, nephrocalcinosis, growth retardation, sensorineural hearing loss, and hypokalemic paralysis. Laboratory investigations revealed proximal tubular dysfunction (low molecular weight proteinuria, generalized hyperaminoaciduria, hypophosphatemia with hyperphosphaturia, and hypouricemia with hyperuricosuria). There was significant hyperoxaluria and laboratory evidence for mild rhabdomyolysis. Under potassium and alkali therapy, proximal tubular abnormalities, muscular enzymes, and oxaluria normalized. A homozygous mutation in the ATP6V1B1 gene, which is responsible for dRTA with early hearing loss, was detected in both siblings. In conclusion, proximal tubular dysfunction and hyperoxaluria may be found in children with dRTA and are reversible under appropriate therapy.     

Analysis of genes encoding laminin β2 and related proteins in patients with Galloway–Mowat syndrome

Galloway-Mowat syndrome (GMS) is a rare autosomal recessive disorder characterized by early onset nephrotic syndrome and microcephaly with various anomalies of the central nervous system. GMS likely represents a heterogeneous group of disorders with hitherto unknown genetic etiology. The clinical phenotype to some extent overlaps that of Pierson syndrome (PS), which comprises congenital nephrotic syndrome and distinct ocular abnormalities but which may also include neurodevelopmental deficits and microcephaly. PS is caused by mutations of LAMB2, the gene encoding laminin beta2. We hypothesized that GMS might be allelic to PS or be caused by defects in proteins that interact with laminin beta2. In a cohort of 18 patients with GMS or a GMS-like phenotype we therefore analyzed the genes encoding laminin beta2 (LAMB2), laminin alpha5 (LAMA5), alpha3-integrin (ITGA3), beta1-integrin (ITGB1) and alpha-actinin-4 (ACTN4), but we failed to find causative mutations in these genes. We inferred that LAMA5, ITGA3, ITGB1, and ACTN4 are not directly involved in the pathogenesis of GMS. We excluded LAMB2 as a candidate gene for GMS. Further studies are required, including linkage analysis in families with GMS to identify genes underlying this disease.     

A randomised, placebo-controlled study to assess the efficacy of twice-daily vardenafil in the treatment of lower urinary tract symptoms secondary to benign prostatic hyperplasia

INTRODUCTION: Benign prostatic hyperplasia (BPH) is associated with bothersome lower urinary tract symptoms (LUTS) and reduced patient quality of life (QoL). Phosphodiesterase (type) 5 (PDE5) inhibitors such as vardenafil are commonly used for the treatment of erectile dysfunction (ED), but have also been shown to improve the symptoms of BPH. This randomised, double-blind, placebo-controlled study investigated the effects of vardenafil on LUTS and QoL in men with BPH/LUTS, with or without concomitant ED. METHODS: Men aged 45-64 yr with BPH/LUTS and an International Prostate Symptom Score (IPSS) > or =12 were randomised to receive either 10mg vardenafil or placebo twice daily. LUTS were assessed with the use of two primary efficacy parameters, IPSS score and maximum urinary flow rate (Qmax), as well as postvoid residual (PVR) urine volume; ED was measured with the use of the erectile function (EF) domain score of the International Index of Erectile Function (IIEF-EF); and QoL was assessed with the Urolifetrade mark QoL-9 questionnaire. RESULTS: After 8 wk of treatment, there was a significant improvement in the IPSS total score in the vardenafil group compared with placebo (-5.9 and -3.6, respectively; p=0.0013). Nominally significant improvements in irritative and obstructive IPSS subscores (p=0.0017 and p=0.0081, respectively), EF (p=0.0001), and Urolife QoL-9 (p<0.0001) were also associated with vardenafil treatment. Qmax and PVR urine volume did not change significantly with treatment, although baseline values were already considered close to normal. Vardenafil was generally well tolerated, with most adverse events considered mild or moderate in severity. CONCLUSIONS: Vardenafil treatment significantly improved LUTS, EF, and QoL in men with BPH/LUTS. Vardenafil may be considered a promising treatment option for men with symptoms secondary to BPH.     

Febrile urinary tract infection in children: ampicillin and trimethoprim insufficient as empirical mono-therapy

The aim of this study was to characterize the pathogens and their antibiotic susceptibilities in defined groups of children (total number 694) with urinary tract infection (UTI) regarding age, first UTI (FUTI) or recurrent UTI (RUTI), renal abnormalities or vesico-ureteric reflux (VUR) in order to optimize empirical antibiotic therapy and prophylaxis. In patients aged between 1 month and 24 months with a first febrile UTI (FUTI; n = 205) the leading pathogen was Escherichia coli (E. coli) (83.4%). In comparison with patients with FUTI, those with RUTI (n = 24) had more Enterococcus and Enterobacter infections and higher resistance rates of E. coli against trimethoprim (TMP), trimethoprim/sulfamethoxazole (SXT) or ampicillin (AMP). Boys with ultrasound-detected renal abnormalities (n = 71) showed 14.2% Pseudomonas and 59.1% E. coli infections versus girls (n = 48) (2.1% Pseudomonas and 93.7% E. coli). Of 390 patients who underwent voiding cysto-urethrography, 31.5% had VUR. Of them, 45.5% received antimicrobial prophylaxis with SXT (n = 30) or cefazolin (n = 26). There was no difference between girls (n = 242) and boys (n = 148) regarding the frequency of VUR and pathogens. There were more TMP- and SXT-resistant E. coli cultures from patients with VUR (37.8%) than from those without VUR (25.8%). Treatment with TMP, SXT and AMP alone appeared to be insufficient in many cases because of high resistance rates of E. coli and other uropathogens.     

Isolation and culture of different epidermal and dermal cell types from human scalp suitable for the development of a therapeutical cell spray

BACKGROUND: Previous studies demonstrated, that cultured epithelial autografts (CEA) can be isolated and skin cell sprays can be produced for application on different types of wounds. The purpose of the present study was to determine which cell types can be isolated from the human scalp and whether these cells can be used for spray transplantation. METHODS: Outer root sheath cells (ORS), keratinocytes, melanocytes, dermal papilla cells (DP), and dermal sheath cells (DSC) were isolated from human scalp tissue. Isolated cells were characterized, expanded and sprayed in an in vitro model. Growth behaviour, morphology and cell counts were compared with non-sprayed cells. RESULTS: With acceptable time, equipment and laboratory personnel a sufficient amount of keratinocytes, ORS, melanocytes, DP cells and DSC cells could be achieved. The cells are sufficient for application as a cell spray. Cells, positive for Integrin alpha6, Cytokeratin 19, CD73 and CD105 were identified within the cultures. CONCLUSIONS: Human scalp is suitable to gain epidermal and dermal cells for the development of therapeutic cell spray transplantation. Further studies have to determine, whether these cells can be combined to produce wound specific skin substitutes.     

The Prognostic Value of Prothrombin Time in Predicting Survival after Major Trauma: a Prospective Analysis of 1,351 Patients from the German Trauma Registry

Background: Early assessment of the individual trauma load in major trauma patients is difficult. A simple and reliable prognostic factor already available in the emergency room would help the emergency physician to make appropriate therapeutic decisions, e. g., when and how to operate on major fractures. The aim of the study was to evaluate the prognostic value of prothrombin time (PT). Patients and Methods: The German Trauma Registry is a prospective, standardized and anonymous documentation of severely injured patients. 3,814 patients were included in the registry. 1,351 patients with an Injury Severity Score (ISS) h 16 and complete data for specific variables (PT, Trauma Score + Injury Severity Score [TRISS], survival until discharge) were included in the study. The PT was measured on the patient's arrival in the emergeny room. Three different analyses were performed. 1. According to clinical judgment, three groups of patients were compared (PT S 60%, PT 40-59%, PT < 40%). A univariate analysis compared therapeutic interventions and outcome variables between the three groups. 2. A receiver-operator-characteristic (ROC) curve analysis compared the performance of PT with the prognostic standard TRISS. 3. A multivariate logistic regression was performed in order to evaluate PT as an independent prognostic variable. Results: PT values showed a good inverse correlation with the severity of injury and the level of therapeutic interventions. The ROC analysis as well as the regression revealed PT as a significant prognostic factor although it showed a slightly worse performance compared to TRISS. Conclusions: As PT, in contrast to TRISS, is readily available already in the emergency room, it can be used as a screening variable for the assessment of a patient's trauma load and thereby help in the decision-making for further operative treatment of major trauma patients.