Risk factors for wound infection in surgery for spinal metastasis

Wound infection rates are generally higher in patients undergoing surgery for spinal metastasis. Risk factors of wound infection in these patients are poorly understood. Purpose To identify demographic and clinical variables that may be associated with patients experiencing a higher wound infection rate. Study design Retrospective study with prospectively collected data of spinal metastasis patients operated consecutively at a University Teaching Hospital, adult spine division which is a tertiary referral centre for complex spinal surgery. Patient sample Ninety-eight patients were all surgically treated, consecutively from January 2009 to September 2011. Three patients had to be excluded due to inadequate data. Outcome measures Physiological measures, with presence or absence of microbiologically proven infection. Methods Various demographic and clinical data were recorded, including age, serum albumin level, blood total lymphocyte count, corticosteroid intake, Malnutrition Universal Screening Tool (MUST) score, neurological disability, skin closure material used, levels of surgery and administration of peri-operative corticosteroids. No funding was received from any sources for this study and as far as we are aware, there are no potential conflict of interest-associated biases in this study. Results Higher probabilities of infection were associated with low albumin level, seven or more levels of surgery, use of delayed/non-absorbable skin closure material and presence of neurological disability. Of these factors, levels of surgery were found to be statistically significant at the 5 % significance level. Conclusion Risk of infection is high (17.9 %) in patients undergoing surgery for spinal metastasis. Seven or more vertebral levels of surgery increase the risk of infection significantly (p < 0.05). Low albumin level and presence of neurological disability appear to show a trend towards increased risk of infection. Use of absorbable skin closure material, age, low lymphocyte count, peri-operative administration of corticosteroids and MUST score do not appear to influence the risk of infection

Flow cytometry-based FRET identifies binding intensities in PPAR[gamma]1 protein-protein interactions in living cells

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Clinical management and microscopic characterisation of fatique-induced failure of a dental implant. Case report

BACKGROUND: Osseointegrated endosseous implants are widely used for the rehabilitation of completely and partially edentulous patients, being the final prosthodontic treatment more predictable and the failures extremely infrequent. A case of fracture of an endosseous dental implant, replacing the maxillary first molar, occurring in a middle-age woman, 5 years after placement is reported. MATERIALS AND METHODS: The difficult management of this rare complication of implant dentistry together with the following rehabilitation is described. Additionally, the authors performed an accurate analysis of the removed fractured implant both by the stereomicroscope and by the confocal laser scanning microscope. RESULTS AND DISCUSSION: The fractured impant showed the typical signs of a fatigue-induced fracture in the coronal portion of the implant together with numerous micro-fractures in the apical one. Three dimensional imaging performed by confocal laser scanning microscope led easily to a diagnosis of "fatigue fracture" of the implant. The biomechanical mechanism of implant fractures when overstress of the implant components due to bending overload is discussed. CONCLUSION: When a fatigue-induced fracture of an dental implant occurs in presence of bending overload, the whole implant suffers a deformation that is confirmed by the alterations (micro-fractures) of the implant observable also in the osseointegrated portion that is easily appraisable by the use of stereomicroscope and confocal laser scanning microscope without preparation of the sample

Radiographic rib fracture nonunion and association with fracture classification in adults with multiple rib fractures without flail segment:A multicenter prospective cohort study

Background: Rib fracture nonunion is a probable cause of chronic pain following chest trauma, although its prevalence remains unknown. The aims of this study were to determine rib fracture nonunion prevalence following nonoperative management and to determine if presence of nonunion was associated with the number of rib fractures, or the rib fracture classification of anatomical location, type, and displacement. Methods: This multicenter prospective cohort study included trauma patients with three or more fractured ribs but without a flail segment, who participated in the nonoperative management group of the FixCon trial between January 2019 and June 2022. The number and classification of rib fractures were assessed on trauma chest CT. Chest CTs conducted six months post-trauma were evaluated for the presence of nonunion. Radiological characteristics of nonunions were compared with normally healed rib fractures using the Mann-Whitney U, χ2 test, and Fisher's exact test as appropriate. A generalized linear model adjusted for multiple observations per patient when assessing the associations between nonunion and fracture characteristics. Results: A total of 68 patients were included with 561 post-traumatic fractures in 429 ribs. Chest CT after six months revealed nonunions in 67 (12 %) rib fractures in 29 (43 %) patients with a median of 2 (P25-P75 1–3) nonunions per patient. Nonunion was most commonly observed in ribs seven to 10 (20–23 %, p &lt; 0.001, adjusted p = 0.006). Nonunion occurred in 14 (5 %) undisplaced, 22 (19 %) offset, and 20 (23 %) displaced rib fractures (p &lt; 0.001). No statistically significant association between rib fracture type and nonunion was found. Conclusions: Forty-three percent of patients with multiple rib fractures had radiographic nonunion six months after trauma. Fractures in ribs seven to 10 and dislocated fractures had an increased risk of rib fracture nonunion.</p

Radiographic rib fracture nonunion and association with fracture classification in adults with multiple rib fractures without flail segment:A multicenter prospective cohort study

Background: Rib fracture nonunion is a probable cause of chronic pain following chest trauma, although its prevalence remains unknown. The aims of this study were to determine rib fracture nonunion prevalence following nonoperative management and to determine if presence of nonunion was associated with the number of rib fractures, or the rib fracture classification of anatomical location, type, and displacement. Methods: This multicenter prospective cohort study included trauma patients with three or more fractured ribs but without a flail segment, who participated in the nonoperative management group of the FixCon trial between January 2019 and June 2022. The number and classification of rib fractures were assessed on trauma chest CT. Chest CTs conducted six months post-trauma were evaluated for the presence of nonunion. Radiological characteristics of nonunions were compared with normally healed rib fractures using the Mann-Whitney U, χ2 test, and Fisher's exact test as appropriate. A generalized linear model adjusted for multiple observations per patient when assessing the associations between nonunion and fracture characteristics. Results: A total of 68 patients were included with 561 post-traumatic fractures in 429 ribs. Chest CT after six months revealed nonunions in 67 (12 %) rib fractures in 29 (43 %) patients with a median of 2 (P25-P75 1–3) nonunions per patient. Nonunion was most commonly observed in ribs seven to 10 (20–23 %, p &lt; 0.001, adjusted p = 0.006). Nonunion occurred in 14 (5 %) undisplaced, 22 (19 %) offset, and 20 (23 %) displaced rib fractures (p &lt; 0.001). No statistically significant association between rib fracture type and nonunion was found. Conclusions: Forty-three percent of patients with multiple rib fractures had radiographic nonunion six months after trauma. Fractures in ribs seven to 10 and dislocated fractures had an increased risk of rib fracture nonunion.</p

Characterization of an Alkali- and Halide-Resistant Laccase Expressed in E. coli: CotA from <i>Bacillus clausii</i>

The limitations of fungal laccases at higher pH and salt concentrations have intensified the search for new extremophilic bacterial laccases. We report the cloning, expression, and characterization of the bacterial cotA from Bacillus clausii, a supposed alkalophilic ortholog of cotA from B. subtilis. Both laccases were expressed in E. coli strain BL21(DE3) and characterized fully in parallel for strict benchmarking. We report activity on ABTS, SGZ, DMP, caffeic acid, promazine, phenyl hydrazine, tannic acid, and bilirubin at variable pH. Whereas ABTS, promazine, and phenyl hydrazine activities vs. pH were similar, the activity of B. clausii cotA was shifted upwards by ~0.5-2 pH units for the simple phenolic substrates DMP, SGZ, and caffeic acid. This shift is not due to substrate affinity (K(M)) but to pH dependence of catalytic turnover: The k(cat) of B. clausii cotA was 1 s⁻¹ at pH 6 and 5 s⁻¹ at pH 8 in contrast to 6 s⁻¹ at pH 6 and 2 s⁻¹ at pH 8 for of B. subtilis cotA. Overall, k(cat)/K(M) was 10-fold higher for B. subtilis cotA at pH(opt). While both proteins were heat activated, activation increased with pH and was larger in cotA from B. clausii. NaCl inhibited activity at acidic pH, but not up to 500-700 mM NaCl in alkaline pH, a further advantage of the alkali regime in laccase applications. The B. clausii cotA had ~20 minutes half-life at 80°C, less than the ~50 minutes at 80°C for cotA from B. subtilis. While cotA from B. subtilis had optimal stability at pH~8, the cotA from B. clausii displayed higher combined salt- and alkali-resistance. This resistance is possibly caused by two substitutions (S427Q and V110E) that could repel anions to reduce anion-copper interactions at the expense of catalytic proficiency, a trade-off of potential relevance to laccase optimization

Early fixation versus conservative therapy of multiple, simple rib fractures (FixCon): protocol for a multicenter randomized controlled trial

Background: Multiple rib fractures are common injuries in both the young and elderly. Rib fractures account for 10% of all trauma admissions and are seen in up to 39% of patients after thoracic trauma. With morbidity and mortality rates increasing with the number of rib fractures as well as poor quality of life at long-term follow-up, multiple rib fractures pose a serious health hazard. Operative fixation of flail chest is beneficial over nonoperative treatment regarding, among others, pneumonia and both intensive care unit (ICU) and hospital length of stay. With no high-quality evidence on the effects of multiple simple rib fracture treatment, the optimal treatment modality remains unknown. This study sets out to investigate outcome of operative fixation versus nonoperative treatment of multiple simple rib fractures. Methods: The proposed study is a multicenter randomized controlled trial. Patients will be eligible if they have three or more multiple simple rib fractures of which at least one is disl

The Dopamine Augmenter L-DOPA Does Not Affect Positive Mood in Healthy Human Volunteers

Dopamine neurotransmission influences approach toward rewards and reward-related cues. The best cited interpretation of this effect proposes that dopamine mediates the pleasure that commonly accompanies reward. This hypothesis has received support in some animal models and a few studies in humans. However, direct assessments of the effect of transiently increasing dopamine neurotransmission have been largely limited to the use of psychostimulant drugs, which elevate brain levels of multiple neurotransmitters in addition to dopamine. In the present study we tested the effect of more selectively elevating dopamine neurotransmission, as produced by administration of the immediate dopamine precursor, L-DOPA (0, 100/25, 200/50 mg, Sinemet), in healthy human volunteers. Neither dose altered positive mood. The results suggest that dopamine neurotransmission does not directly influence positive mood in humans