No abstract

Photosensitive dyes or photo sensitizers (PS) in combination with visible light and oxygen produce reactive oxygen species that kill cells in the process known as photodynamic therapy (PDT). Antimicrobial PDT employs PS that is selective for microbial cells and is a new treatment for infections. Most antimicrobial PS is based on tetrapyrrole or phenothiazinium structures that have been synthesized to carry quaternary cationic charges or basic amino groups. However we recently showed that cationic-substituted fullerene derivative were highly effective in killing a broad spectrum of microbial cells after illumination with white light. In the present report we compared a new group of synthetic fullerene derivatives that possessed either basic or quaternary amino groups as antimicrobial PS against Gram-positive (Staphylococcus aureus), Gram-negative bacteria (Escherichia coli) and fungi (Candida albicans). Quantitative structure-function relationships were derived with LogP and hydrophilic lipophilic balance parameters. Compounds with non-quaternary amino groups tended to form nanoaggregates in water and were only effective against S. aureus. The most important determinant of effectiveness was an increased number of quaternary cationic groups that were widely dispersed around the fullerene cage to minimize aggregation. S. aureus was most susceptible; E. coli was intermediate, while C. albicans was the most resistant species tested. The high effectiveness of antimicrobial PDT with quaternized fullerenes suggest they may have applications in treatment of superficial infections (for instance in wounds and burns) where light penetration into tissue is not problematic.

Objectives: The pulmonary nodule is an important diagnostic and therapeutic problem. Diagnostic certainty is only obtained by histological examination. Mini-invasive surgery allows removal of the nodule with minimal sequelae for the patient. Methods: From October 1991 to December 2006, 370 resections for a pulmonary nodule were performed at our Department of General Surgery of the University of Milan: 276 wedge resections and 94 lobectomies. Results: Frozen section was performed in all the wedge resections, and in the presence of cancer (77 cases), whenever possible (61 cases), the intervention was converted to lobectomy in the same session. In the other 94 cases, the nodule was removed by lobectomy due to the impossibility of performing a wedge resection. Conclusions: Despite the refinement of diagnostic techniques, only exeresis of a pulmonary nodule ensures a definitive diagnosis, thus resolving the problem of benign pathologies and initiating the correct therapy for malignant lesions in the same session.

Background: The prevalence of classifiable and unclassifiable causes of lung fibrosis and its implications for survival are mostly unknown in combined pulmonary fibrosis and emphysema (CPFE). Materials and methods: Patients with > 10% involvement of both emphysema and lung fibrosis seen over 11 years at our institution were reviewed independently by expert radiologists for fibrotic and emphysematous findings and overall fibrotic CT pattern. Underlying interstitial lung disease (ILD) diagnoses and baseline demographic and clinical characteristics were collated and assessed for predictors of comparative survival. Results: In this retrospective cohort, 179 CPFE patients were identified and categorized as 58 usual interstitial pneumonia/idiopathic pulmonary fibrosis (UIP/IPF) (32%), 42 secondary ILD (23%), and 79 unclassifiable ILD (44%). The most prevalent (47%) radiologic pattern was 'unclassifiable', followed by 'consistent' and 'possible' UIP pattern in 38%. Adjusted predictors of mortality for the cohort as a whole included age (HR 1.03[1.01-1.06], P = 0.002), percent predicted diffusing capacity for carbon monoxide (unit HR 0.97 [0.96-0.99], P = 0.001), honeycombing ], P = 0.04), and right ventricular dysfunction ], P = 0.002). Survival was similar between CPFE with secondary ILD and CPFE with UIP/IPF, while CPFE with unclassifiable ILD had better comparative survival (Log rank = 0.026). Conclusions: Our findings suggest only about a third of CPFE patients represent suspected UIP/IPF; the majority were clinically and radiologically unclassifiable ILD whose survival was comparatively better. Identifiable or secondary causes of lung fibrosis in CPFE occurred in about a fifth of presenting patients.

Background & PurposeAllogenic blood transfusion in elective orthopaedic surgery is best avoided owing to its associated risks. Total knee replacement often requires blood transfusion, more so when bilateral surgery is performed. Many strategies are currently being employed to reduce the amount of peri-operative allogenic transfusions. Anti-fibrinolytic compounds such as aminocaproic acid and tranexamic acid have been used systemically in perioperative settings with promising results. This study aimed to evaluate the effectiveness of tranexamic acid in reducing allogenic blood transfusion in total knee replacement surgery.MethodologyThis was a retrospective cohort study conducted on patients undergoing total knee replacement during the time period November 2005 to November 2008. Study population was 99 patients, of which 70 underwent unilateral and 29 bilateral knee replacement. Forty-seven patients with 62 (49.5%) knees (group-I) had received tranexamic acid (by surgeon preference) while the remaining fifty-two patients with 66 (51.5%) knees (group-II) had did not received any tranexamic acid either pre- or post-operatively.ResultsThe mean drop in the post-operative haemoglobin concentration in Group-II for unilateral and bilateral cases was 1.79 gm/dl and 2.21 gm/dl, with a mean post-operative drainage of 1828 ml (unilateral) and 2695 ml (bilateral). In comparison, the mean drop in the post-op haemoglobin in Group-I was 1.49 gm/dl (unilateral) and 1.94 gm/dl (bilateral), with a mean drainage of 826 ml (unilateral) and 1288 ml (bilateral) (p-value < 0.001).InterpretationTranexamic acid is effective in reducing post-operative drainage and requirement of blood transfusion after knee replacement.

Our results suggest that midodrine is being increasingly used as an adjunct to increase mean arterial pressure and facilitate weaning of vasopressors in the ICU. Prospective trials are required to further establish the appropriate timing, efficacy, safety, and cost-effectiveness of midodrine use in ICU patients.

A bronchopleural fistula (BPF) is a communication between the pleural space and the bronchial tree. BPFs are challenging to diagnose and are associated with a high morbidity and mortality. Sequential balloon occlusion is commonly used for localization of a BPF. We describe our experience with 4 cases of successful localization of the BPF by instillation of methylene blue into the pleural space through a pigtail catheter, with simultaneous bronchoscopic visualization of dye in the tracheobronchial tree. Two patients were treated with endobronchial valves and 3 had a surgical thoracic muscle flap placed.

Background and objective: Pleuroscopy with pleural biopsy has a high sensitivity for malignant pleural effusion (MPE). Because MPEs tend to recur, concurrent diagnosis and treatment of MPE during pleuroscopy is desired. However, proceeding directly to treatment at the time of pleuroscopy requires confidence in the on-site diagnosis. The study's primary objective was to create a predictive model to estimate the probability of MPE during pleuroscopy. Methods: A prospective observational multicentre cohort study of consecutive patients undergoing pleuroscopy was conducted. We used a logistic regression model to evaluate the probability of MPE with relation to visual assessment, rapid on-site evaluation (ROSE) of touch preparation and presence of pleural nodules/masses on computed tomography (CT). To assess the model's prediction accuracy, a bootstrapped training/testing approach was utilized to estimate the cross-validated area under the receiver operating characteristic curve. Results: Of the 201 patients included in the study, 103 had MPE. Logistic regression showed that higher level of malignancy on visual assessment is associated with higher odds of MPE (OR = 34.68, 95% CI = 9.17-131.14, p < 0.001). The logistic regression also showed that higher level of malignancy on ROSE of touch preparation is associated with higher odds of MPE (OR = 11.63, 95% CI = 3.85-35.16, p < 0.001). Presence of pleural nodules/masses on CT is associated with higher odds of MPE (OR = 6.61, 95% CI = 1.97-22.1, p = 0.002). A multivariable logistic regression model of final pathologic status with relation to visual assessment, ROSE of touch preparation and presence of pleural nodules/masses on CT had a cross-validated AUC of 0.94 (95% CI = 0.91-0.97). Conclusion: A prediction model using visual assessment, ROSE of touch preparation and CT scan findings demonstrated excellent predictive accuracy for MPE. Further validation studies are needed to confirm our findings.