Neochordae implantation versus leaflet resection in mitral valve posterior leaflet prolapse and dilated left ventricle: a propensity score matching comparison with long-term follow-up

OBJECTIVES

Uncorrected severe mitral regurgitation (MR) due to posterior prolapse leads to left ventricular dilatation. At this stage, mitral valve repair becomes mandatory to avoid permanent myocardial injury. However, which technique among neochoardae implantation and leaflet resection provides the best results in this scenario remains unknown.

METHODS

We selected 332 patients with left ventricular dilatation and severe degenerative MR due to posterior leaflet (PL) prolapse who underwent neochoardae implantation (85 patients) or PL resection (247 patients) at our institution between 2008 and 2020. A propensity score matching analysis was carried on to decrease the differences at baseline.

RESULTS

Matching yielded 85 neochordae implantations and 85 PL resections. At 10 years, freedom from cardiac death and freedom from mitral valve reoperation were 92.6 ± 6.1% vs 97.8 ± 2.1% and 97.7 ± 2.2% vs 95 ± 3% in the neochordae group and in the PL resection group, respectively. The MR ≥2+ recurrence rate was 23.9 ± 10% in the neochordae group and 20.8 ± 5.8% in the PL resection group (P = 0.834) at 10 years. At the last follow-up, the neochordae group showed a higher reduction of left ventricular end-diastolic diameter (44 vs 48 mm; P = 0.001) and a better ejection fraction (60% vs 55%; P < 0.001) compared to PL resection group.

CONCLUSIONS

In this subgroup of patients, both neochordae implantation and leaflet resection provide excellent durability of the repair in the long term. Neochordae implantation might have a better effect on dilated left ventricle.

TRI-SCORE: a single-Centre validation study

BACKGROUND AND AIMS

The TRI-SCORE is a recently published risk score for predicting in-hospital mortality in patients undergoing isolated tricuspid valve surgery (ITVS). The aim of this study is to externally validate the ability of the TRI-SCORE in predicting in-hospital and long-term mortality following ITVS.

METHODS

A retrospective review of our institutional database was carried out to identify all patients undergoing isolated tricuspid valve repair or replacement from March 1997 to March 2021. The TRI-SCORE was calculated for all patients. Discrimination of the TRI-SCORE was assessed using receiver operating characteristic curves. Accuracy of the models was tested calculating the Brier score. Finally, a COX regression was employed to evaluate the relationship between the TRI-SCORE value and long-term mortality.

RESULTS

A total of 176 patients were identified and the median TRI-SCORE was 3 (1-5). The cut-off value identified for increased risk of isolated ITVS was 5. Regarding in-hospital outcomes, the TRI-SCORE showed high discrimination (area under the curve 0.82), and high accuracy (Brier score 0.054). This score showed also very good performance in predicting long-term mortality (at 10 years HR: 1.47, 95% CI [1.31-1.66], p < 0.001), with high discrimination (area under the curve >0.80 at 1-5 and 10 years) and high accuracy values (Brier score 0.179).

CONCLUSIONS

This external validation confirm the good performance of the TRI-SCORE in predicting in-hospital mortality. Moreover, the score showed also very good performance in predicting the long-term mortality.

A prospective study on the efficacy of dupilumab in chronic rhinosinusitis with type 2 inflammation

Objective

Treatment for chronic rhinosinusitis with nasal polyps (CRSwNP) includes endoscopic sinus surgery and topic and/or systemic corticosteroids, which have only temporary effects. The development of biologic therapies has provided a new treatment paradigm for CRSwNP. Dupilumab is the only biological approved in Italy for CRSwNP, but its efficacy in a real-life context is still scarce.

Methods

We carried out a monocentric prospective study at our institution with a 6-month follow-up on patients administered biweekly 300 mg dupilumab therapy for CRSwNP, prescribed according to EPOS 2020 criteria. Patients were evaluated at baseline and every 2 months.

Results

Median values at baseline and 6 months were, respectively, 3/12 and 8/12 for the Brief Smell Identification Test (p = 0.005), 5/8 and 2/8 for the Nasal Polyp Score (p < 0.001), 10/20 and 6/20 for the Lund-Kennedy score (p < 0.001), 65/110 and 14/110 for the Sinonasal Outcome Test (p < 0.001), and 15/25 and 23/25 for the Asthma Control Test score (p = 0.009). Adverse events were mild, consisting mainly in discomfort at the site of injection. Four patients developed asymptomatic hypereosinophilia. The treatment was not discontinued in any patient.

Conclusions

Dupilumab was confirmed to be an effective and safe treatment for CRSwNP, as previously seen in registrational studies.

AI-SCoRE (artificial intelligence-SARS CoV2 risk evaluation): a fast, objective and fully automated platform to predict the outcome in COVID-19 patients

Purpose

To develop and validate an effective and user-friendly AI platform based on a few unbiased clinical variables integrated with advanced CT automatic analysis for COVID-19 patients’ risk stratification.

Material and Methods

In total, 1575 consecutive COVID-19 adults admitted to 16 hospitals during wave 1 (February 16-April 29, 2020), submitted to chest CT within 72 h from admission, were retrospectively enrolled.

In total, 107 variables were initially collected; 64 extracted from CT. The outcome was survival.

A rigorous AI model selection framework was adopted for models selection and automatic CT data extraction. Model performances were compared in terms of AUC. A web–mobile interface was developed using Microsoft PowerApps environment. The platform was externally validated on 213 COVID-19 adults prospectively enrolled during wave 2 (October 14-December 31, 2020).

Results

The final cohort included 1125 patients (292 non-survivors, 26%) and 24 variables. Logistic showed the best performance on the complete set of variables (AUC = 0.839 ± 0.009) as in models including a limited set of 13 and 5 variables (AUC = 0.840 ± 0.0093 and AUC = 0.834 ± 0.007). For non-inferior performance, the 5 variables model (age, sex, saturation, well-aerated lung parenchyma and cardiothoracic vascular calcium) was selected as the final model and the extraction of CT-derived parameters was fully automatized. The fully automatic model showed AUC = 0.842 (95% CI: 0.816–0.867) on wave 1 and was used to build a 0–100 scale risk score (AI-SCoRE). The predictive performance was confirmed on wave 2 (AUC 0.808; 95% CI: 0.7402–0.8766).

Conclusions

AI-SCoRE is an effective and reliable platform for automatic risk stratification of COVID-19 patients based on a few unbiased clinical data and CT automatic analysis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11547-022-01518-0.

Long-term efficacy, safety and neurotolerability of MATRix regimen followed by autologous transplant in primary CNS lymphoma: 7-year results of the IELSG32 randomized trial

219 HIV-negative adults ≤70 years with primary CNS lymphoma (PCNSL) were enrolled in the randomized IELSG32 trial. Enrolled patients were randomly assigned to receive methotrexate-cytarabine (arm A), or methotrexate-cytarabine-rituximab (B), or methotrexate-cytarabine-thiotepa-rituximab (MATRix; arm C). A second randomization allocated patients with responsive/stable disease to whole-brain irradiation (WBRT) or carmustine-thiotepa-conditioned autologous transplantation (ASCT). First results, after a median follow-up of 30 months, showed that MATRix significantly improves outcome, with both WBRT and ASCT being similarly effective. However, sound assessment of overall survival (OS), efficacy of salvage therapy, late complications, secondary tumors, and cognitive impairment requires longer follow-up. Herein, we report the results of this trial at a median follow-up of 88 months. As main findings, MATRix was associated with excellent long-lasting outcome, with a 7-year OS of 21%, 37%, and 56% respectively for arms A, B, and C. Notably, patients treated with MATRix and consolidation had a 7-year OS of 70%. The superiority of arm B on arm A suggests a benefit from the addition of rituximab. Comparable efficacy of WBRT and ASCT was confirmed. Salvage therapy was ineffective; benefit was recorded only in patients with late relapse re-treated with methotrexate. Eight (4%) patients developed a second cancer. Importantly, MATRix and ASCT did not result in higher non-relapse mortality or second tumors incidence. Patients who received WBRT experienced impairment in attentiveness and executive functions, whereas patients undergoing ASCT experienced improvement in these functions as well as in memory and quality of life.

Mobilization-based chemotherapy-free engraftment of gene-edited human hematopoietic stem cells

Hematopoietic stem/progenitor cell gene therapy (HSPC-GT) is proving successful to treat several genetic diseases. HSPCs are mobilized, harvested, genetically corrected ex vivo, and infused, after the administration of toxic myeloablative conditioning to deplete the bone marrow (BM) for the modified cells. We show that mobilizers create an opportunity for seamless engraftment of exogenous cells, which effectively outcompete those mobilized, to repopulate the depleted BM. The competitive advantage results from the rescue during ex vivo culture of a detrimental impact of mobilization on HSPCs and can be further enhanced by the transient overexpression of engraftment effectors exploiting optimized mRNA-based delivery. We show the therapeutic efficacy in a mouse model of hyper IgM syndrome and further developed it in human hematochimeric mice, showing its applicability and versatility when coupled with gene transfer and editing strategies. Overall, our findings provide a potentially valuable strategy paving the way to broader and safer use of HSPC-GT.

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HSPC mobilizers create an opportunity to engraft exogenous cells in depleted niches

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Ex vivo culture endows HSPCs with migration advantage by rescuing CXCR4 expression

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Cultured HSPCs outcompete mobilized HSPCs for engraftment in depleted BM niches

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Transient engraftment enhancers coupled with gene editing confer a competitive advantage

Exocrine pancreas function is impaired in adult relatives of patients with type 1 diabetes

AIMS

Alterations of the exocrine pancreas have been reported in type 1 diabetes, but their contribution to the pathogenesis of the disease is poorly understood. Here, we investigated markers of exocrine pancreas dysfunction in individuals at-risk of developing type 1 diabetes.

METHODS

Serum P-amylase and lipase levels were assessed in samples obtained from healthy controls, patients with new onset type 1 diabetes, relatives participating to the TrialNet Pathway to Prevention who were, at blood collection, autoantibody negative or positive for a single autoantibody (low-risk individuals), and positive for multiple autoantibodies (high-risk individuals). Linear mixed models were adopted to estimate variation of pancreatic enzymes among the groups and to evaluate the influence of high-risk HLA genotypes and residual beta cell function on exocrine pancreas function.

RESULTS

In adults, but not children, reduced levels of P-amylase and lipase were shown in at-risk individuals, including (for P-amylase levels only) those at low-risk, and in T1Dnew. Furthermore, while high-risk HLA genotypes negatively affected P-amylase levels in autoantibody negative adult individuals, fasting C-peptide levels did not correlate with pancreatic enzyme levels.

CONCLUSIONS

Exocrine pancreas dysfunction precedes the onset of type 1 diabetes in adult at-risk individuals and may be unrelated to fasting C-peptide levels.

Role of anaesthesia in endoscopic and external dacryocystorhinostomy: A meta-analysis of 3282 cases

Distal acquired lacrimal obstruction is a common adulthood pathology whose primary treatment is represented by EXT-DCR and END-DCR. When considering their influencing factors, the role of the type of anaesthesia applied during these surgeries has a major role. The aim of this study is to systematically analyse the influence of general and local/regional anaesthesia on the final success rates of EXT-DCR and END-DCR. Primary EXT-DCR and END-DCR articles published later than 2000 with at least 50 single clinician procedures were selected. Exclusion criteria included acute dacryocystitis, tumours, studies focussing on revision surgeries, surgeries with adjunctive procedures, not clearly demarcated surgeons, mixed cohort study of acquired and congenital disorders. This systematic review was conducted in accordance with MOOSE guidelines; where feasible, a meta-analysis of the collected results was conducted. As a result, 11,445 articles were selected of which 2741 were examined after screening, and 16 included after full text review (0.6% of the initial papers). Among all papers included, the number of EXT-DCR was not enough to provide a solid analysis of the effect of anaesthesia; conversely, a significant difference of success rate was noted between local anaesthesia + sedation (85.1%, IC 77.8%-90.4%), and general anaesthesia (90.8%, IC 88.8%-92.4%) in END-DCR (p = 0.048). In conclusion, END-DCR performed with general anaesthesia should be considered as the solution of choice; however, local anaesthesia, eventually associated with a sedation, can be used as an alternative in selected cases. No meaningful conclusions could be drawn for EXT-DCR, due to the lack of data.

MYD88 L265P mutation and interleukin-10 detection in cerebrospinal fluid are highly specific discriminating markers in patients with primary central nervous system lymphoma: results from a prospective study

Reliable biomarkers are needed to avoid diagnostic delay and its devastating effects in patients with primary central nervous system (CNS) lymphoma (PCNSL). We analysed the discriminating sensitivity and specificity of myeloid differentiation primary response (88) (MYD88) L265P mutation (mut-MYD88) and interleukin-10 (IL-10) in cerebrospinal fluid (CSF) of both patients with newly diagnosed (n = 36) and relapsed (n = 27) PCNSL and 162 controls (118 CNS disorders and 44 extra-CNS lymphomas). The concordance of MYD88 mutational status between tumour tissue and CSF sample and the source of ILs in PCNSL tissues were also investigated. Mut-MYD88 was assessed by TaqMan-based polymerase chain reaction. IL-6 and IL-10 messenger RNA (mRNA) was assessed on PCNSL biopsies using RNAscope technology. IL levels in CSF were assessed by enzyme-linked immunosorbent assay. Mut-MYD88 was detected in 15/17 (88%) PCNSL biopsies, with an 82% concordance in paired tissue-CSF samples. IL-10 mRNA was detected in lymphomatous B cells in most PCNSL; expression of IL-6 transcripts was negligible. In CSF samples, mut-MYD88 and high IL-10 levels were detected, respectively, in 72% and 88% of patients with newly diagnosed PCNSL and in 1% of controls; conversely, IL-6 showed a low discriminating sensitivity and specificity. Combined analysis of MYD88 and IL-10 exhibits a sensitivity and specificity to distinguish PCNSL of 94% and 98% respectively. Similar figures were recorded in patients with relapsed PCNSL. In conclusion, high detection rates of mut-MYD88 and IL-10 in CSF reflect, respectively, the MYD88 mutational status and synthesis of this IL in PCNSL tissue. These biomarkers exhibit a very high sensitivity and specificity in detecting PCNSL both at initial diagnosis and relapse. Implications of these findings in patients with lesions unsuitable for biopsy deserve to be investigated.

Influence of Surgical Techniques on Endoscopic Dacryocystorhinostomy: A Systematic Review and Meta-analysis

Objective

Endoscopic endonasal dacryocystorhinostomy (END-DCR) has increased as a valid alternative to the classic external approach to treat distal lacrimal obstruction. Different surgical varieties of the END-DCR approach have been proposed with no clear understanding of the best surgical technique.

Data Source

A comprehensive research was performed in PubMed, Embase, SCOPUS, and Cochrane databases with a final search on March 2020.

Review Methods

The aim of this search was to identify relevant END-DCR procedures performed with mechanical (Mecn-END-DCR) and powered (Pow-END-DCR) approaches to compare their functional success rate. In addition, the influence of mucosal flaps was evaluated. Articles were selected only if they were published later than 2000 and had at least 50 single-clinician surgical procedures performed. Excluded articles included acute infections, cancers, mixed cohort study, and revision cases.

Results

A total of 11,445 publications were identified and 2741 reviewed after screening; 15 articles were included after full-text review (0.6% of the initial articles reviewed). The mean success rate was 91.34% (95% CI, 87.1%-94.3%) for Pow-END-DCR and 89.5% (95% CI, 86.5%-91.9%) for Mecn-END-DCR with no significant difference between the surgical approaches ( P = .43). For mucosal flaps performed during END-DCR, the mean success rate was 89% (95% CI, 86%-91%) if mucosal flaps were used and 92% (95% CI, 88%-95%) if they were not used, with no statistical difference present ( P = .14).

Conclusions

Our analyses suggest that there are no differences in outcomes between mechanical and powered approaches in END-DCR and that mucosal flap preservation is not essential to achieve a superior END-DCR outcome.

Impact of Post-Surgical Therapies on Endoscopic and External Dacryocystorhinostomy: Systematic Review and Meta-Analysis

Background

Epiphora is a common ophthalmologic sign that is most commonly caused by distal acquired lacrimal obstruction. Recent data have demonstrated that external dacryocystorhinostomy (EXT-DCR) and endoscopic endonasal dacryocystorhinostomy (END-DCR) can be considered the treatments of choice. However, different post-surgical medical therapies are available and are currently used to improve surgical outcomes, although no direct comparison has been performed.

Objective

To analyse the influence of post-surgical medical treatments on END-DCR and EXT-DCR outcomes.

Methods

A structured search was conducted using the U.S. National Library of Medicine (PubMed), EMBASE, SCOPUS, and Cochrane databases with a final search performed in May 2020. The research identified papers published later than 2000 with at least 50 single clinician procedures performed in EXT-DCR and END-DCR. Articles that studied acute infections, revision cases, mixed cohort studies of acquired and congenital obstruction, and tumour were excluded. The influence of systemic antibiotic/steroids, local application of mitomycin C, nasal/ocular antibiotic, nasal/ocular steroids and nasal decongestants was analysed.

Results

In total, 11,445 papers were selected, 2,741 of which were reviewed after screening, and 18 included after full text review (0.6% of the initial articles reviewed) which involved 3,590 procedures. Considering the low number of publications on EXT-DCR, statistical analysis of post-surgical therapy was not feasible. In END-DCR, the analyses were performed only for nasal steroids (p = 0.58), oral antibiotics (p = 0.45) and nasal decongestant (p = 0.27), which demonstrated no meaningful influence. Given the variable association between adjunctive medical therapies, pharmacologic molecular heterogeneity and modality/concentration of application, these results should be considered critically. Additionally, no differences were seen for application of silicone stenting, whereas, no statistical analysis was performed for mitomycin C.

Conclusions

Given the high success rate of EXT-DCR and END-DCR and the heterogeneity of literature data, the effective influence of post-surgical medical therapy is difficult to identify. Future large prospective randomized studies could help in detecting the optimal adjunctive therapy for these surgeries.

Long-lasting efficacy and safety of lenalidomide maintenance in patients with relapsed diffuse large B-cell lymphoma who are not eligible for or failed autologous transplantation

We report final results of a phase II trial addressing efficacy and feasibility of lenalidomide maintenance in patients with chemosensitive relapse of diffuse large B-cell lymphoma (DLBCL) not eligible for or failed after autologous stem cell transplantation (ASCT). Patients with relapsed DLBCL who achieved at least a partial response to salvage chemoimmunotherapy were enrolled and treated with lenalidomide 25 mg/day for 21 of 28 days for 2 years or until progression or unacceptable toxicity. Primary endpoint was 1-year PFS. Forty-six of 48 enrolled patients were assessable. Most patients had IPI ≥2, advanced stage and extranodal disease before the salvage treatment that led to trial registration; 28 (61%) patients were older than 70 years. Lenalidomide was well tolerated. With the exception of neutropenia, grade-4 toxicities occurred in <1% of courses. Three patients died of complications during maintenance and three died due to second cancers at 32 to 64 months. There were 13 SAEs recorded in 12 patients; all these patients but two recovered. Lenalidomide was interrupted due to toxicity in other 6 patients, and 25 patients required dose reduction (transient in 21). At 1 year from registration, 31 patients were progression free. After a median follow-up of 65 (range 39-124) months, 22 patients remain progression free, with a 5-year PFS of 48% ± 7%. The duration of response to lenalidomide was longer than response to prior treatment in 30 (65%) patients. Benefit was observed both in de novo and transformed DLBCL, germinal-center-B-cell and nongerminal-center-B-cell subtypes. Twenty-six patients are alive (5-year OS 62% ± 7%). With the limitations of a nonrandomized design, these long-term results suggest that lenalidomide maintenance might bring benefit to patients with chemosensitive relapse of DLBCL not eligible for or failed after ASCT. Lenalidomide was associated with durable disease control and was well tolerated in this elderly population. Further investigations on immunomodulatory drugs as maintenance in these high-risk patients are warranted.

Predictive Score for Identifying Survival and Recurrence Risk Profiles in Patients Undergoing Ventricular Tachycardia Ablation: The I-VT Score

BACKGROUND

Several distinct risk factors for arrhythmia recurrence and mortality following ventricular tachycardia (VT) ablation have been described. The effect of concurrent risk factors has not been assessed so far; thus, it is not yet possible to estimate these risks for a patient with several comorbidities. The aim of the study was to identify specific risk groups for mortality and VT recurrence using the Survival Tree (ST) analysis method.

METHODS

In 1251 patients 16 demographic, clinical and procedure-related variables were evaluated as potential prognostic factors using ST analysis using a recursive partitioning algorithm that searches for relationships among variables. Survival time and time to VT recurrence in groups derived from ST analysis were compared by a log-rank test. A random forest analysis was then run to extract a variable importance index and internally validate the ST models.

RESULTS

Left ventricular ejection fraction, implantable cardioverter defibrillator/cardiac resynchronization device, previous ablation were, in hierarchical order, identified by ST analysis as best predictors of VT recurrence, while left ventricular ejection fraction, previous ablation, Electrical storm were identified as best predictors of mortality. Three groups with significantly different survival rates were identified. Among the high-risk group, 65.0% patients were survived and 52.1% patients were free from VT recurrence; within the medium- and low-risk groups, 84.0% and 97.2% patients survived, 72.4% and 88.4% were free from VT recurrence, respectively.

CONCLUSIONS

Our study is the first to derive and validate a decisional model that provides estimates of VT recurrence and mortality with an effective classification tree. Preprocedure risk stratification could help optimize periprocedural and postprocedural care.

Niacin-mediated Tace activation ameliorates CMT neuropathies with focal hypermyelination

Charcot–Marie–Tooth (CMT) neuropathies are highly heterogeneous disorders caused by mutations in more than 70 genes, with no available treatment. Thus, it is difficult to envisage a single suitable treatment for all pathogenetic mechanisms. Axonal Neuregulin 1 (Nrg1) type III drives Schwann cell myelination and determines myelin thickness by ErbB2/B3‐PI3K–Akt signaling pathway activation. Nrg1 type III is inhibited by the α‐secretase Tace, which negatively regulates PNS myelination. We hypothesized that modulation of Nrg1 levels and/or secretase activity may constitute a unifying treatment strategy for CMT neuropathies with focal hypermyelination as it could restore normal levels of myelination. Here we show that in vivo delivery of Niaspan, a FDA‐approved drug known to enhance TACE activity, efficiently rescues myelination in the Mtmr2^−/− mouse, a model of CMT4B1 with myelin outfoldings, and in the Pmp22^+/− mouse, which reproduces HNPP (hereditary neuropathy with liability to pressure palsies) with tomacula. Importantly, we also found that Niaspan reduces hypermyelination of Vim (vimentin)^−/− mice, characterized by increased Nrg1 type III and Akt activation, thus corroborating the hypothesis that Niaspan treatment downregulates Nrg1 type III signaling.

IL-17A impairs host tolerance during airway chronic infection by Pseudomonas aeruginosa

Resistance and tolerance mechanisms participate to the interplay between host and pathogens. IL-17-mediated response has been shown to be crucial for host resistance to respiratory infections, whereas its role in host tolerance during chronic airway colonization is still unclear. Here, we investigated whether IL-17-mediated response modulates mechanisms of host tolerance during airways chronic infection by P. aeruginosa. First, we found that IL-17A levels were sustained in mice at both early and advanced stages of P. aeruginosa chronic infection and confirmed these observations in human respiratory samples from cystic fibrosis patients infected by P. aeruginosa. Using IL-17a^−/− or IL-17ra^−/− mice, we found that the deficiency of IL-17A/IL-17RA axis was associated with: i) increased incidence of chronic infection and bacterial burden, indicating its role in the host resistance to P. aeruginosa; ii) reduced cytokine levels (KC), tissue innate immune cells and markers of tissue damage (pro-MMP-9, elastin degradation, TGF-β₁), proving alteration of host tolerance. Blockade of IL-17A activity by a monoclonal antibody, started when chronic infection is established, did not alter host resistance but increased tolerance. In conclusion, this study identifies IL-17-mediated response as a negative regulator of host tolerance during P. aeruginosa chronic airway infection.

Tracking the immunopathological response to Pseudomonas aeruginosa during respiratory infections

Repeated cycles of infections, caused mainly by Pseudomonas aeruginosa, combined with a robust host immune response and tissue injury, determine the course and outcome of cystic fibrosis (CF) lung disease. As the disease progresses, P. aeruginosa adapts to the host modifying dramatically its phenotype; however, it remains unclear whether and how bacterial adaptive variants and their persistence influence the pathogenesis and disease development. Using in vitro and murine models of infection, we showed that P. aeruginosa CF-adaptive variants shaped the innate immune response favoring their persistence. Next, we refined a murine model of chronic pneumonia extending P. aeruginosa infection up to three months. In this model, including CFTR-deficient mice, we unveil that the P. aeruginosa persistence lead to CF hallmarks of airway remodelling and fibrosis, including epithelial hyperplasia and structure degeneration, goblet cell metaplasia, collagen deposition, elastin degradation and several additional markers of tissue damage. This murine model of P. aeruginosa chronic infection, reproducing CF lung pathology, will be instrumental to identify novel molecular targets and test newly tailored molecules inhibiting chronic inflammation and tissue damage processes in pre-clinical studies.

Identification of the Arabidopsis RAM/MOR signalling network: adding new regulatory players in plant stem cell maintenance and cell polarization

BACKGROUND AND AIMS

The RAM/MOR signalling network of eukaryotes is a conserved regulatory module involved in co-ordination of stem cell maintenance, cell differentiation and polarity establishment. To date, no such signalling network has been identified in plants.

METHODS

Genes encoding the bona fide core components of the RAM/MOR pathway were identified in Arabidopsis thaliana (arabidopsis) by sequence similarity searches conducted with the known components from other species. The transcriptional network(s) of the arabidopsis RAM/MOR signalling pathway were identified by running in-depth in silico analyses for genes co-regulated with the core components. In situ hybridization was used to confirm tissue-specific expression of selected RAM/MOR genes.

KEY RESULTS

Co-expression data suggested that the arabidopsis RAM/MOR pathway may include genes involved in floral transition, by co-operating with chromatin remodelling and mRNA processing/post-transcriptional gene silencing factors, and genes involved in the regulation of pollen tube polar growth. The RAM/MOR pathway may act upstream of the ROP1 machinery, affecting pollen tube polar growth, based on the co-expression of its components with ROP-GEFs. In silico tissue-specific co-expression data and in situ hybridization experiments suggest that different components of the arabidopsis RAM/MOR are expressed in the shoot apical meristem and inflorescence meristem and may be involved in the fine-tuning of stem cell maintenance and cell differentiation.

CONCLUSIONS

The arabidopsis RAM/MOR pathway may be part of the signalling cascade that converges in pollen tube polarized growth and in fine-tuning stem cell maintenance, differentiation and organ polarity.

Evaluating effect of symptoms heterogeneity on decision-making ability in obsessive-compulsive disorder

AIMS

Despite having a univocal definition, obsessive-compulsive disorder (OCD) shows a remarkably phenotypic heterogeneity. The published reports show impaired decision-making in OCD patients, using tasks such as the Iowa Gambling Task (IGT). We wanted to verify the hypothesis of an IGT worse performance in a large sample of OCD patients and healthy control (HC) subjects and to examine the relation between neuropsychological performance in IGT and the OCD symptoms heterogeneity.

METHODS

Binary data from the Yale-Brown Obsessive Compulsive Scale collected on a large sample of OCD patients were analyzed using a multidimensional item response theory model to explore the underlying structure of data, thus revealing latent factors. Factor scores were categorized into quartiles. Then, for each factor, we identified patients respectively with the highest versus lowest score. We evaluated whether symptom dimensions affect the probability of a correct answer over time generalized, during IGT performance, fitting a generalized linear mixed model.

RESULTS

We found a general deficit in ambiguous decision-making in OCD compared to HC. Moreover, our findings suggested that OCD symptoms heterogeneity affects decision-making learning abilities during IGT. In fact, while 'Symmetry' and 'Washing' patients showed a learning curve during the task, other subgroups did not.

CONCLUSIONS

Our study confirmed previous findings suggesting that OCD is characterized by a deficit in decision-making under uncertainty. Moreover, our study gave evidence about biological specificity for each symptom dimension in OCD. Data were discussed in the context of the somatic marker hypothesis, which was hypothesized to be reduced in OCD patients.

Osteochondral repair by a novel interconnecting collagen-hydroxyapatite substitute: a large-animal study

A novel three-dimensional bicomponent substitute made of collagen type I and hydroxyapatite was tested for the repair of osteochondral lesions in a swine model. This scaffold was assembled by a newly developed method that guarantees the strict integration between the organic and the inorganic parts, mimicking the biological tissue between the chondral and the osseous phase. Thirty-six osteochondral lesions were created in the trochlea of six pigs; in each pig, two lesions were treated with scaffolds seeded with autologous chondrocytes (cell+group), two lesions were treated with unseeded scaffolds (cell- group), and the two remaining lesions were left untreated (untreated group). After 3 months, the animals were sacrificed and the newly formed tissue was analyzed to evaluate the degree of maturation. The International Cartilage Repair Society (ICRS) macroscopic assessment showed significantly higher scores in the cell- and untreated groups when compared with the cell+ group. Histological evaluation showed the presence of repaired tissue, with fibroblast-like and hyaline-like areas in all groups; however, with respect to the other groups, the cell- group showed significantly higher values in the ICRS II histological scores for "cell morphology" and for the "surface/superficial assessment." While the scaffold seeded with autologous chondrocytes promoted the formation of a reparative tissue with high cellularity but low glycosaminoglycans (GAG) production, on the contrary, the reparative tissue observed with the unseeded scaffold presented lower cellularity but higher and uniform GAG distribution. Finally, in the lesions treated with scaffolds, the immunohistochemical analysis showed the presence of collagen type II in the peripheral part of the defect, indicating tissue maturation due to the migration of local cells from the surroundings. This study showed that the novel osteochondral scaffold was easy to handle for surgical implantation and was stable within the site of lesion; at the end of the experimental time, all implants were well integrated with the surrounding tissue and no signs of synovitis were observed. The quality of the reparative tissue seemed to be superior for the lesions treated with the unseeded scaffolds, indicating the promising potential of this novel biomaterial for use in a one-stage procedure for osteochondral repair.

The benefit of synthetic versus biological patch augmentation in the repair of posterosuperior massive rotator cuff tears: a 3-year follow-up study

BACKGROUND

Rotator cuff repair typically results in a satisfactory, although variable, clinical outcome. However, anatomic failure of the repaired tendon often occurs.

HYPOTHESIS

Patch augmentation can improve the results of open rotator cuff repair by supporting the healing process, protecting the suture, and reducing friction in the subacromial space.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A total of 152 patients with a posterosuperior massive rotator cuff tear were treated by open repair only (control group; n = 51; mean age, 67.06 ± 4.42 years), open repair together with collagen patch augmentation (collagen group; n = 49; mean age, 66.53 ± 5.17 years), or open repair together with polypropylene patch augmentation (polypropylene group; n = 52; mean age, 66.17 ± 5.44 years) and were retrospectively studied. Patients were evaluated preoperatively and after 36 months with a visual analog scale (VAS) and the University of California, Los Angeles (UCLA) shoulder rating scale and by measuring elevation of the scapular plane and strength with a dynamometer. The VAS and UCLA scores were also obtained 2 months postoperatively. Tendon integrity was assessed after 1 year by ultrasound. Patients were homogeneous as per the preoperative assessment.

RESULTS

After 2 months, results (mean ± standard deviation) for the control, collagen, and polypropylene groups, respectively, were as follows: VAS scores were 6.96 ± 1.11, 6.46 ± 1.02, and 4.92 ± 0.90, while UCLA scores were 11.29 ± 1.46, 11.40 ± 1.51, and 19.15 ± 1.99. After 36 months, the mean scores for the respective groups were 3.66 ± 1.05, 4.06 ± 1.02, and 3.28 ± 1.10 for the VAS and 14.88 ± 1.98, 14.69 ± 1.99, and 24.61 ± 3.22 for the UCLA scale. In addition, after 36 months, elevation on the scapular plane was 140.68° ± 9.84°, 140.61° ± 12.48°, and 174.71° ± 8.18°, and abduction strength was 8.73 ± 0.54 kg, 9.03 ± 0.60 kg, and 13.79 ± 0.64 kg for the control, collagen, and polypropylene groups, respectively. The retear rate after 12 months was 41% (21/51) for the control group, 51% (25/49) for the collagen group, and 17% (9/52) for the polypropylene group. In particular, the reduced 12-month retear rate and the increased UCLA scores, abduction strength, and elevation at 3-year follow-up were statistically significant for patients treated with a polypropylene patch compared with those treated with repair only or with a collagen patch.

CONCLUSION

Polypropylene patch augmentation of rotator cuff repair was demonstrated to significantly improve the 36-month outcome in terms of function, strength, and retear rate.

Facioscapulohumeral muscular dystrophy region gene 1 over-expression causes primary defects of myogenic stem cells

Over-expression of FSHD Region Gene 1 (FRG1) in mice, frogs and worms leads to muscular and vascular abnormalities. Nevertheless, the mechanism that follows FRG1 over-expression and finally leads to muscular defects is currently unknown. Here, we show that the earliest phenotype displayed by FRG1 mice is a postnatal muscle-growth defect. Long before the development of muscular dystrophy, FRG1 mice exhibit also a muscle regeneration impairment. Ex-vivo and in-vivo experiments revealed that FRG1 over-expression causes myogenic stem-cell activation, proliferative, clonogenic and differentiation defects. A comparative gene expression profiling of WT and FRG1 muscles from young pre-dystrophic mice identified differentially expressed genes in several gene categories and networks that could explain the emerging tissue and myogenic stem-cell defects. Overall, our study provides new insights in the pathways regulated by FRG1 and suggests that muscle-stem cells defects could contribute to the pathology of FRG1 mice.

Whole-mount in situ detection of microRNAs on Arabidopsis tissues using Zip Nucleic Acid probes

MicroRNAs (miRNAs) affect fundamental processes of development. In plants miRNAs regulate organ development, transition to flowering, and responses to abiotic/biotic stresses. To understand the biological role of miRNAs, in addition to identifying their targeted transcripts, it is necessary to characterize the spatiotemporal regulation of their expression. Many methods have been used to define the set of organ-specific miRNAs by tissue dissection and miRNA profiling but none of them can describe their tissue and cellular distribution at the high resolution provided by in situ hybridization (ISH). This article describes the setup and optimization of a whole-mount ISH protocol to target endogenous miRNAs on intact Arabidopsis seedlings using DIG-labeled Zip Nucleic Acid (ZNA) oligonucleotide probes. Automation of the main steps of the procedure by robotized liquid handling has also been implemented in the protocol for best reproducibility of results, enabling running of ISH experiments at high throughput.

Response of CFTR-deficient mice to long-term chronic Pseudomonas aeruginosa infection and PTX3 therapy

BACKGROUND

 In cystic fibrosis (CF) patients, chronic lung infection and inflammation due to Pseudomonas aeruginosa contribute to the decline of lung function. The increased prevalence of multidrug resistance among bacteria and the adverse effects of antiinflammatory agents highlight the need for alternative therapeutic approaches that should be tested in a relevant animal model.

METHODS

 Gut-corrected CF and non-CF mice were chronically infected with a multidrug-resistant P. aeruginosa strain and treated with the long pentraxin PTX3. Body weight, bacterial count, inflammation, and lung pathology were evaluated after 12 days. PTX3 localization in CF sputum specimens was analyzed by immunofluorescence.

RESULTS

 Chronic P. aeruginosa infection developed similarly in CF and non-CF mice but differed in terms of the inflammatory response. Leukocyte recruitment in the airways, cytokine levels, and chemokine levels were significantly higher in CF mice, compared with non-CF mice. PTX3 treatment, which facilitates phagocytosis of pathogens, reduced P. aeruginosa colonization and restored airway inflammation in CF mice to levels observed in non-CF mice. The presence of PTX3 in CF sputum, in leukocytes, or bound to P. aeruginosa macrocolonies, as well as previous data on PTX3 polymorphisms in colonized CF patients, confirm the relevance of this molecule.

CONCLUSIONS

 These findings represent a step forward in demonstrating the therapeutic potential of PTX3 in CF.

PRaTo: a web-tool to select optimal primer pairs for qPCR

An essential pre-requisite to perform sound quantitative real-time polymerase chain reaction (qPCR) assays is to design outstanding primer pairs. This means they must have a good efficiency and be not prone to produce multiple amplicons or primer dimer products. To circumvent these issues, several softwares are available to help primer design. Although satisfactory computer-aided primer design tools are available for standard PCR, less efforts were done to provide specific methods for selection of optimal primer pairs for qPCR. We have developed PRaTo a web-based tool that enables checking and ranking of primers pairs for their attitude to perform optimally and reliably when used in qPCR experiments. PRaTo is available at http://prato.daapv.unipd.it.

Transcriptome analysis reveals coordinated spatiotemporal regulation of hemoglobin and nitrate reductase in response to nitrate in maize roots

Given the importance of nitrogen for plant growth and the environmental costs of intense fertilization, an understanding of the molecular mechanisms underlying the root adaptation to nitrogen fluctuations is a primary goal for the development of biotechnological tools for sustainable agriculture. This research aimed to identify the molecular factors involved in the response of maize roots to nitrate. cDNA-amplified fragment length polymorphism was exploited for comprehensive transcript profiling of maize (Zea mays) seedling roots grown with varied nitrate availabilities; 336 primer combinations were tested and 661 differentially regulated transcripts were identified. The expression of selected genes was studied in depth through quantitative real-time polymerase chain reaction and in situ hybridization. Over 50% of the genes identified responded to prolonged nitrate starvation and a few were identified as putatively involved in the early nitrate signaling mechanisms. Real-time results and in situ localization analyses demonstrated co-regulated transcriptional patterns in root epidermal cells for genes putatively involved in nitric oxide synthesis/scavenging. Our findings, in addition to strengthening already known mechanisms, revealed the existence of a new complex signaling framework in which brassinosteroids (BRI1), the module MKK2-MAPK6 and the fine regulation of nitric oxide homeostasis via the co-expression of synthetic (nitrate reductase) and scavenging (hemoglobin) components may play key functions in maize responses to nitrate.

AAV6-mediated systemic shRNA delivery reverses disease in a mouse model of facioscapulohumeral muscular dystrophy

Treatment of dominantly inherited muscle disorders remains a difficult task considering the need to eliminate the pathogenic gene product in a body-wide fashion. We show here that it is possible to reverse dominant muscle disease in a mouse model of facioscapulohumeral muscular dystrophy (FSHD). FSHD is a common form of muscular dystrophy associated with a complex cascade of epigenetic events following reduction in copy number of D4Z4 macrosatellite repeats located on chromosome 4q35. Several 4q35 genes have been examined for their role in disease, including FRG1. Overexpression of FRG1 causes features related to FSHD in transgenic mice and the FRG1 mouse is currently the only available mouse model of FSHD. Here we show that systemic delivery of RNA interference expression cassettes in the FRG1 mouse, after the onset of disease, led to a dose-dependent long-term FRG1 knockdown without signs of toxicity. Histological features including centrally nucleated fibers, fiber size reduction, fibrosis, adipocyte accumulation, and inflammation were all significantly improved. FRG1 mRNA knockdown resulted in a dramatic restoration of muscle function. Through RNA interference (RNAi) expression cassette redesign, our method is amenable to targeting any pathogenic gene offering a viable option for long-term, body-wide treatment of dominant muscle disease in humans.

Pseudomonas aeruginosa microevolution during cystic fibrosis lung infection establishes clones with adapted virulence

RATIONALE

During long-term lung infection in patients with cystic fibrosis (CF), Pseudomonas aeruginosa strains develop mutations leading to clonal expansion. This microevolution is believed to be correlated with a reduced virulence.

OBJECTIVES

We tested this hypothesis in models of lung infection, using mice with different genetic backgrounds.

METHODS

From infected airways of six patients with CF, 25 P. aeruginosa clones were isolated during a period of up to 16.3 years and genotypically and phenotypically characterized. Virulence of the 8 early, 6 intermediate, and 11 late CF isolates and 5 environmental strains was assessed by monitoring acute mortality versus survival and P. aeruginosa chronic persistence versus lung clearance in mice of different genetic backgrounds, including CF mice.

MEASUREMENTS AND MAIN RESULTS

Different patients harbored clonally unrelated strains, but early, intermediate, and late P. aeruginosa isolates from single patients were clonally related, allowing comparative in vivo analysis. Although late isolates were attenuated in causing acute mortality in the mouse models, compared with early and intermediate clonal isolates and environmental strains, they did not differ from early and intermediate clonal isolates in their capacity to establish chronic infection and cause extensive inflammation in the murine respiratory tract.

CONCLUSIONS

Our findings indicate that clonal expansion of P. aeruginosa strains during microevolution within CF lungs leads to populations with altered but not reduced virulence. These P. aeruginosa clones with adapted virulence play a critical role in the pathogenesis of chronic infections and may serve to define virulence determinants as targets for novel therapies.

The effects of a comprehensive rehabilitation program of Alzheimer's Disease in a hospital setting

Introduction. The evidence for the clinical effectiveness of cognitive rehabilitation in patients with Alzheimer’s Disease (AD) is debated. Therefore it is important to collect more evidence about the outcome of non-pharmacological therapy of dementia. Material and Methods. We report data concerning the rehabilitation of 50 patients with probable AD admitted during a 17-month period in a specialized unit. Participants were affected by dementia ranging from mild to severe. The patients were treated with the Reality Orientation Therapy (ROT), integrated, when needed, with individualised cognitive approaches. The results concern: the cognitive status, evaluated by means of the Mini Mental State Examination (MMSE), the functional status, evaluated with the Activity of Daily Living (ADL) scale, the assessment of psychological and behavioural disorders measured with the Neuropsychiatry Inventory (NPI). The cognitive, functional, and psychopathological assessments were administered at admission and discharge. Results. The mean MMSE scores at admission and discharge were respectively 16.06 and 17.54 (Wilcoxon Ranks Test: p = 0.005). Mean ADL scores were 4.86 at admission and 5.02 at discharge (p = 0.011). Mean NPI scores were respectively 21.46 and 12.26 (p = < 0.001). Conclusions. This survey of the 17-month experience suggests that a comprehensive treatment program may have beneficial effects on cognitive, functional, and in particular neuropsychiatric outcomes. The results should be verified with a randomised clinical trial.

Double-blind, placebo-controlled trial to assess the efficacy and tolerability of mepartricin in the treatment of BPH

BACKGROUND

Mepartricin, a semisynthetic polyene derivative with a favorable effect on urethro-prostatic function, was clinically evaluated, adopting the diagnostic and research criteria recommended by the First International Consultation on BPH.

METHODS

A multicenter, randomized, double-blind, parallel-group study compared mepartricin 40 mg/daily to placebo in the treatment of 196 patients with newly diagnosed BPH and mild-to-moderate symptomatology. International Prostate Symptom Score (I-PSS), quality of life (QoL) index and maximum urinary flow-rate (Qmax) were determined every 4 weeks for 6 months; postvoiding volume, prostate volume, and prostate-specific antigen (PSA) were assessed after 3 and 6 months of therapy.

RESULTS

Mepartricin was shown to determine a statistically significant improvement over placebo in I-PSS and QoL index from month 2 onwards, and a significant linear increase in Qmax over the study period. At month 6, the improvement in the mepartricin and placebo groups in I-PSS, QoL index, and Qmax was 6.3 (standard error (SE) 0.51) and 4.2 (SE 0.60) points (P = 0.003), 0.99 (SE 0.14) and 0.62 (SE 0.12) points (P = 0.036), and 2.7 (SE 0.46) and 1.2 (SE 0.46) ml/sec (P = 0.051), respectively. No significant differences were noted in postvoiding residual volume, prostate volume, or PSA. Mepartricin tolerability was good, showing no adverse events on sexual function.

CONCLUSIONS

Mepartricin proved to be an effective treatment of benign prostatic hyperplasia, determining an improvement in symptoms, quality of life, and peak urinary flow.

In-vitro activity of 3-azinomethyl-rifamycin (SPA-S-565) against Chlamydia trachomatis

The in-vitro activity of a 3-azinomethyl-rifamycin (SPA-S-565) against Chlamydia trachomatis was compared to that of rifampicin and of erythromycin. The compound showed excellent activity for standard strains as well as isolates from patients with sexually transmitted diseases, being more active than the other drugs tested. SPA-S-565 also showed a low frequency of emergence of resistance. Passage of standard strains at sub-inhibitory concentrations caused an increase in MIC values of rifampicin while those for SPA-S-565 remained unchanged.

Past, present and future trends in tuberculosis epidemiology in a region of northern Italy. An analysis carried out through the application of a simulation model (Eskimo)

The epidemiological model Eskimo has been utilized to simulate some epidemiological parameters relative to tuberculosis in a restricted geographical area of northern Italy. After having identified a series of features relative to the regimens applied in the area in the period 1982-86 and which were found to be compatible with the observed data, this hypothesis has been utilized to project data on tuberculosis for the period 1986-1996. The results have indicated that the incidence in the area should stabilize around values of 20 new cases per year (per 100,000 population). A decrease in the incidence can be expected to occur only if the regimens so far employed are brought to a greater part of the patients' population (increasing coverage). The effects of importing the disease from developing countries through immigration and of the AIDS epidemic are likely to negatively affect the trend of tuberculosis incidence in the future.

Eskimo: an epidemiological simulation kinetic model for tuberculosis

A simple, easy to use, kinetic model allowing the simulation of the main epidemiological parameters of tuberculosis and of the financial costs associated with the implementation of different anti-tuberculous policies, has been developed and described. The model, which has been denominated "ESKIMO" (Epidemiological Simulation Kinetic Model) can be utilized on a personal computer and requires, for its use, the knowledge of a series of easily available census data relative to a given country or geographical area, an essential epidemiological profile of the disease in the same area and data which characterize one or more antituberculous treatments in therapeutic and financial terms. The rationale of the model, which is a multicompartemental system, derive from an analysis of the relationships (transfer rates) between sub-populations of individuals in relation to tuberculosis either when the dynamic state of the system is governed by "natural forces" (no treatment) or when an external action is applied to it with an aim to alter its internal pathways in a favourable sense (vaccination, long-term hospitalization, chemotherapy). The model is based on the assumption that the main objective of any antituberculous program is the reduction in size of the subpopulation of patients who can infect other individuals and therefore perpetuate the disease. Validation and projection tests carried out through Eskimo seem to indicate that concentrating the analysis on the effect of various treatments on this group of patients simplifies the calculations while the relative precision of the estimates of other parameters is very satisfactory. The results of several simulations substantiate and quantify the opinions expressed by several experts in the past that the policy of applying cheap regimens of low efficacy to a relatively small fraction of the patients' population, as frequently done in developing countries, not only does not alter the trend of the disease but produces essentially negative results (increase in the number of new cases and in the frequency of resistant M. tuberculosis). Treatment with highly effective regimens of the same number of patients as those treated now (constant coverage) and therefore without the extra costs resulting from the improvement of the available sanitary infrastructures, produces much better results in clinical terms and overall saving of financial resources.

Comparative bioavailability of isoniazid, rifampin, and pyrazinamide administered in free combination and in a fixed triple formulation designed for daily use in antituberculosis chemotherapy. II. Two-month, daily administration study

The time course of the plasma concentrations of isoniazid, rifampin, and pyrazinamide was assessed in a group of 13 patients with lung tuberculosis treated over a period of 2 months on a continuous daily basis with a fixed triple combination of the same drugs. The blood kinetics of the three antituberculosis drugs were determined on Days 1, 15, 30, and 60 of treatment. The triple combination employed in this study contained 50 mg isoniazid, 120 mg rifampin, and 300 mg pyrazinamide per tablet, the number of tablets ranging from four to seven per day according to the body weight of the patients. Almost superimposable plasma concentration curves for isoniazid were observed during the 4 days of the study. For rifampin, a fall in the plasma concentrations at the time intervals after the peak was observed comparing the data on Day 1 with those on Days 15, 30, and 60, which did not differ from each other. This finding is thought to be due to the well-known phenomenon of self-induction, which leads to an increased rate of disposal of the antibiotic from the blood compartment within the first and second weeks of continuous treatment. For pyrazinamide, an equilibrium in the opposite sense as that of rifampin seemed to take place within the 2 months of the study. Because of the relatively high plasma levels observed 24 h after each administration, an increase in plasma concentrations with respect to those observed on Day 1 was found on Days 15, 30, and 60, the levels on these days no differing from each other.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparative bioavailability of isoniazid, rifampin, and pyrazinamide administered in free combination and in a fixed triple formulation designed for daily use in antituberculosis chemotherapy. I. Single-dose study

A comparative bioavailability study of the antituberculosis drugs isoniazid, rifampin, and pyrazinamide was carried out in a group of 10 healthy volunteers after administration of the three compounds, once in individual association and once in a combined, fixed preparation. The investigation was designed as an open, crossover study where each subject received five tablets of a preparation containing 50 mg isoniazid, 120 mg rifampin, and 300 mg pyrazinamide (corresponding to a total dose of 250 mg isoniazid, 600 mg rifampin, and 1,500 mg pyrazinamide). The same doses were administered in the session where the drugs were combined using the individual formulations. For each subject and experimental session, 15 blood samples were collected over a period of 24 h, and the plasma concentrations of the three drugs were assessed. The results indicated the absence of negative pharmacokinetic interactions between the drugs when administered in both free and this new, fixed combination.