FixNCut: single-cell genomics through reversible tissue fixation and dissociation

The use of single-cell technologies for clinical applications requires disconnecting sampling from downstream processing steps. Early sample preservation can further increase robustness and reproducibility by avoiding artifacts introduced during specimen handling. We present FixNCut, a methodology for the reversible fixation of tissue followed by dissociation that overcomes current limitations. We applied FixNCut to human and mouse tissues to demonstrate the preservation of RNA integrity, sequencing library complexity, and cellular composition, while diminishing stress-related artifacts. Besides single-cell RNA sequencing, FixNCut is compatible with multiple single-cell and spatial technologies, making it a versatile tool for robust and flexible study designs.

An atlas of cells in the human tonsil

Palatine tonsils are secondary lymphoid organs (SLOs) representing the first line of immunological defense against inhaled or ingested pathogens. We generated an atlas of the human tonsil composed of >556,000 cells profiled across five different data modalities, including single-cell transcriptome, epigenome, proteome, and immune repertoire sequencing, as well as spatial transcriptomics. This census identified 121 cell types and states, defined developmental trajectories, and enabled an understanding of the functional units of the tonsil. Exemplarily, we stratified myeloid slan-like subtypes, established a BCL6 enhancer as locally active in follicle-associated T and B cells, and identified SIX5 as putative transcriptional regulator of plasma cell maturation. Analyses of a validation cohort confirmed the presence, annotation, and markers of tonsillar cell types and provided evidence of age-related compositional shifts. We demonstrate the value of this resource by annotating cells from B cell-derived mantle cell lymphomas, linking transcriptional heterogeneity to normal B cell differentiation states of the human tonsil.

Tumor heterogeneity and tumor-microglia interactions in primary and recurrent IDH1-mutant gliomas

The isocitrate dehydrogenase (IDH) gene is recurrently mutated in adult diffuse gliomas. IDH-mutant gliomas are categorized into oligodendrogliomas and astrocytomas, each with unique pathological features. Here, we use single-nucleus RNA and ATAC sequencing to compare the molecular heterogeneity of these glioma subtypes. In addition to astrocyte-like, oligodendrocyte progenitor-like, and cycling tumor subpopulations, a tumor population enriched for ribosomal genes and translation elongation factors is primarily present in oligodendrogliomas. Longitudinal analysis of astrocytomas indicates that the proportion of tumor subpopulations remains stable in recurrent tumors. Analysis of tumor-associated microglia/macrophages (TAMs) reveals significant differences between oligodendrogliomas, with astrocytomas harboring inflammatory TAMs expressing phosphorylated STAT1, as confirmed by immunohistochemistry. Furthermore, inferred receptor-ligand interactions between tumor subpopulations and TAMs may contribute to TAM state diversity. Overall, our study sheds light on distinct tumor populations, TAM heterogeneity, TAM-tumor interactions in IDH-mutant glioma subtypes, and the relative stability of tumor subpopulations in recurrent astrocytomas.

Influence of Malignant Pleural Fluid from Lung Adenocarcinoma Patients on Neutrophil Response

Simple Summary

This study provides novel information about the role of neutrophils in malignant pleural effusion (MPE) and hallmarks their clinical relevance. Since these cells have emerged as important regulators of cancer, we characterized their phenotype and functions in MPE microenvironment. We found that neutrophil-derived products (degranulation molecules and neutrophil extracellular traps (NETs)) were increased in MPE. In addition, NETs were associated with a worse outcome in lung adenocarcinoma patients with MPE.

Abstract

Malignant pleural effusion (MPE) is a common severe complication of advanced lung adenocarcinoma (LAC). Neutrophils, an essential component of tumor infiltrates, contribute to tumor progression and their counts in MPE have been associated with worse outcome in LAC. This study aimed to evaluate phenotypical and functional changes of neutrophils induced by MPE to determine the influence of MPE immunomodulatory factors in neutrophil response and to find a possible association between neutrophil functions and clinical outcomes. Pleural fluid samples were collected from 47 LAC and 25 heart failure (HF) patients. We measured neutrophil degranulation products by ELISA, oxidative burst capacity and apoptosis by flow cytometry, and NETosis by fluorescence. The concentration of degranulation products was higher in MPE-LAC than in PE-HF. Functionally, neutrophils cultured with MPE-LAC had enhanced survival and neutrophil extracellular trap (NET) formation but had reduced oxidative burst capacity. In MPE, NETosis was positively associated with MMP-9, P-selectin, and sPD-L1 and clinically related to a worse outcome. This is the first study associating NETs with a worse outcome in MPE. Neutrophils likely contribute to tumor progression through the release of NETs, suggesting that they are a potential therapeutic target in LAC.

Phase angle by electrical bioimpedance is a predictive factor of hospitalisation, falls and mortality in patients with cirrhosis

The phase angle is a versatile measurement to assess body composition, frailty and prognosis in patients with chronic diseases. In cirrhosis, patients often present alterations in body composition that are related to adverse outcomes. The phase angle could be useful to evaluate prognosis in these patients, but data are scarce. The aim was to analyse the prognostic value of the phase angle to predict clinically relevant events such as hospitalisation, falls, and mortality in patients with cirrhosis. Outpatients with cirrhosis were consecutively included and the phase angle was determined by electrical bioimpedance. Patients were prospectively followed to determine the incidence of hospitalisations, falls, and mortality. One hundred patients were included. Patients with phase angle ≤ 4.6° (n = 31) showed a higher probability of hospitalisation (35% vs 11%, p = 0.003), falls (41% vs 11%, p = 0.001) and mortality (26% vs 3%, p = 0.001) at 2-year follow-up than patients with PA > 4.6° (n = 69). In the multivariable analysis, the phase angle and MELD-Na were independent predictive factors of hospitalisation and mortality. Phase angle was the only predictive factor for falls. In conclusion, the phase angle showed to be a predictive marker for hospitalisation, falls, and mortality in outpatients with cirrhosis.

Reliability of iCare ic100 Rebound Tonometry and Agreement With Goldmann Applanation Tonometry in Healthy and Post-myopic LASIK Patients

PRECIS

Rebound tonometry offers excellent reliability for obtaining intraocular pressure (IOP) measurements in healthy and post-myopic laser-assisted in situ keratomileusis (LASIK) patients regardless of corneal parameters and axial length and regardless of the instillation of ocular topical anesthesia.

PURPOSE

The purpose of this study was to assess the reliability of rebound tonometry, its agreement with Goldmann applanation tonometry (GAT) and its concordance after topical anesthesia in a group of nonoperated healthy patients and a group of post-myopic LASIK patients.

PATIENTS AND METHODS

Fifty-four patients were included in this prospective observational, case-control study. Patients were divided into 2 groups: control (n=32, 26.7±6.1 y) and LASIK (n=22, 35.8±7.6 y). Measurements of IOP were carried out using the iCare ic100 tonometer and GAT. The repeatability, intersession and interobserver reproducibility, GAT interchangeability and concordance after topical anesthesia of the iCare ic100 tonometer were assessed.

RESULTS

Clinical reliability of the iCare ic100 was excellent in terms of repeatability [intraclass correlation coefficient (ICC)=0.909 and 0.951 in control and ICC=0.938 and 0.961 in LASIK] as well as interobserver reproducibility (ICC=0.896 in control and 0.916 in LASIK) and concordance after anesthesia (ICC=0.910 in control and 0.972 in LASIK) in both groups. Intersession reproducibility was clinically good in nonoperated patients (ICC=0.758 and 0.849) and excellent in LASIK patients (ICC=0.878 and 0.904), although statistically significant differences were obtained in the control group for both examiners (P=0.003 for examiner 1 and P=0.04 for examiner 2). Agreement with GAT was good in both groups (ICC=0.805 in control and 0.790 in LASIK), although statistically different (P<0.001 and P=0.02, respectively). Finally, the iCare ic100 reliability was independent of corneal parameters and axial length in both groups (P>0.05 for all parameters).

CONCLUSIONS

Rebound tonometry offers good or excellent clinical reliability in both healthy and post-myopic LASIK patients. This article highlights the efficacy of iCare ic100 rebound tonometry as a reliable tool for the measurement of IOP and the management of glaucoma in healthy patients and patients undergoing myopic LASIK surgery.

Bacteriophages immunomodulate the response of monocytes

Bacteriophages are present in fluids from cirrhosis patients. However, their effect on the immune response is unknown. In this work, we explore the role of phages in the phenotype, function, and cytokine production of monocytes. We stimulated healthy monocytes with five different butanol-purified phage suspensions infective for Gram-negative and Gram-positive bacteria. We studied the expression of the monocyte markers involved in lipopolysaccharide recognition (LPS; CD14), antigen presentation (HLA-DR) and co-stimulation (CD86), and the concentration of induced cytokines (TNF-α, IFN-α, and IL-10) by phages. To confirm the direct role of phages without the interference of contaminating soluble LPS in phage suspensions, polymyxin B was added to the cell cultures. Phagocytosis experiments were assessed by flow cytometry using labeled phage suspensions. We observed that butanol-purified phages reduced the surface levels of CD14 and CD86 in monocytes and increased the secreted levels of TNF-α and IL-10 compared with the control sample containing only butanol buffer. All phage suspensions showed downregulation of HLA-DR expression but only Staphylococcus aureus phage contaminated with Escherichia coli reached statistical significance. The addition of polymyxin B did not restore the monocytic response induced by phages, suggesting that the effect was not caused by the presence of LPS. Monocytes were able to phagocyte phages in a dose- and time-dependent manner. To conclude, the phagocytosis of butanol-purified phages altered the phenotype and cytokine production of monocytes suggesting they become tolerogenic.

Immunological and genetic kinetics from diagnosis to clinical progression in chronic lymphocytic leukemia

BACKGROUND

Mechanisms driving the progression of chronic lymphocytic leukemia (CLL) from its early stages are not fully understood. The acquisition of molecular changes at the time of progression has been observed in a small fraction of patients, suggesting that CLL progression is not mainly driven by dynamic clonal evolution. In order to shed light on mechanisms that lead to CLL progression, we investigated longitudinal changes in both the genetic and immunological scenarios.

METHODS

We performed genetic and immunological longitudinal analysis using paired primary samples from untreated CLL patients that underwent clinical progression (sampling at diagnosis and progression) and from patients with stable disease (sampling at diagnosis and at long-term asymptomatic follow-up).

RESULTS

Molecular analysis showed limited and non-recurrent molecular changes at progression, indicating that clonal evolution is not the main driver of clinical progression. Our analysis of the immune kinetics found an increasingly dysfunctional CD8⁺ T cell compartment in progressing patients that was not observed in those patients that remained asymptomatic. Specifically, terminally exhausted effector CD8⁺ T cells (T-bet^dim/-Eomes^hiPD1^hi) accumulated, while the the co-expression of inhibitory receptors (PD1, CD244 and CD160) increased, along with an altered gene expression profile in T cells only in those patients that progressed. In addition, malignant cells from patients at clinical progression showed enhanced capacity to induce exhaustion-related markers in CD8⁺ T cells ex vivo mainly through a mechanism dependent on soluble factors including IL-10.

CONCLUSIONS

Altogether, we demonstrate that the interaction with the immune microenvironment plays a key role in clinical progression in CLL, thereby providing a rationale for the use of early immunotherapeutic intervention.

Clinical impact of confinement due to the COVID-19 pandemic on patients with fibromyalgia: a cohort study

OBJECTIVES

To our knowledge, the impact of the COVID-19 pandemic on fibromyalgia (FM) patients has not been studied before. FM patients often experience clinical impairment with stress. The aim of this study was to determine whether severity of FM increases because of confinement by the COVID-19 pandemic.

METHODS

This prospective study includes patients from the Combined Index of Severity of Fibromyalgia (ICAF) cohort who met the 2010 ACR FM criteria. In this cohort, all patients have a periodical evaluation of their quality of life through two questionnaires, the ICAF, which assesses the ability to perform daily living activities, anxiety and depression, and through the Patient Global Impression of Change (PGIC), which assesses overall change after a therapeutical intervention. Pre- and post-confinement measurements were analysed. Inferential statistical analysis and ANOVA for repeated measurements were used.

RESULTS

A total of 93 patients received a phone consultation, (95.5% females), mean (SD) age of 48.23 (8.38) years. Four patients were excluded as presenting COVID-19 and 51 (57%) completed the post-confinement ICAF. Following confinement, 25 (49%) patients got worse (group-worse) and 26 (51%) patients experienced no change or improved (group-stable). Comparisons between pre- and post-confinement ICAF did not show significant differences in both groups. Passive coping was significantly different in group-worse in pre-confinement evaluation. In the 80% of patients with passive coping predominance there were no changes in coping strategy.

CONCLUSIONS

No clinical impairment due to COVID-19 confinement occurred. The perceived worsening among FM patients relies primarily on how patients cope with their disease, without a real impact on clinical manifestations.

Adherence to subcutaneous biological therapies in patients with inflammatory rheumatic diseases and inflammatory bowel disease: a systematic review

Aim: To assess adherence to subcutaneous biologicals in adults with inflammatory rheumatic diseases or inflammatory bowel disease and evaluate factors possibly associated with adherence. Materials & methods: Systematic searches were conducted of main databases from January 2000 to June 2019. Results: 41 articles (32 full papers and nine abstracts) were included in the review. Among studies which used a medication possession ratio threshold of ≥80% as the end point, adherence varied from 28.8 to 89.4%. Possible predictors of adherence were older age, professional or family member support, belief in medication necessity, lower concerns about medication and monthly versus weekly administration. Conclusion: Considerable variability in adherence rates across published studies reflects study heterogeneity and the absence of a 'gold standard' to measure adherence.

Cell free circulating tumor DNA in cerebrospinal fluid detects and monitors central nervous system involvement of B-cell lymphomas

The levels of cell free circulating tumor DNA (ctDNA) in plasma correlate with treatment response and outcome in systemic lymphomas. Notably, in brain tumors, the levels of ctDNA in the cerebrospinal fluid (CSF) are higher than in plasma. Nevertheless, their role in central nervous system (CNS) lymphomas remains elusive. We evaluated the CSF and plasma from 19 patients: 6 restricted CNS lymphomas, 1 systemic and CNS lymphoma, and 12 systemic lymphomas. We performed whole exome sequencing or targeted sequencing to identify somatic mutations of the primary tumor, then variant-specific droplet digital polymerase chain reaction was designed for each mutation. At time of enrollment, we found ctDNA in the CSF of all patients with restricted CNS lymphoma but not in patients with systemic lymphoma without CNS involvement. Conversely, plasma ctDNA was detected in only 2 out of 6 patients with restricted CNS lymphoma with lower variant allele frequencies than CSF ctDNA. Moreover, we detected CSF ctDNA in one patient with CNS lymphoma in complete remission and in one patient with systemic lymphoma, 3 and 8 months before CNS relapse was confirmed, indicating that CSF ctDNA might detect CNS relapse earlier than conventional methods. Finally, in two cases with CNS lymphoma, CSF ctDNA was still detected after treatment even though no tumoral cells were observed by flow cytometry (FC), indicating that CSF ctDNA detected residual disease better than FC. In conclusion, CSF ctDNA can detect CNS lesions better than plasma ctDNA and FC. In addition, CSF ctDNA predicted CNS relapse in CNS and systemic lymphomas.

Frailty in outpatients with cirrhosis: A prospective observational study

BACKGROUND AND AIM

Frailty is increasingly recognized as a major prognostic factor in cirrhosis in addition to conventional liver insufficiency scores. The aim was to compare the prevalence and characteristics of frailty between patients with cirrhosis and controls, and to analyse its prognostic value.

METHODS

We included outpatients with cirrhosis and age- and gender-matched non-cirrhotic controls. Frailty was defined according to the Fried frailty criteria. In patients with cirrhosis, we analysed the ability of the degree of frailty to predict a composite endpoint, consisting of hospitalization, admission to a long-term care centre, falls or death.

RESULTS

We included 135 patients with cirrhosis and 135 controls. The prevalence of frailty was higher among patients with cirrhosis: 35 (25.9%) frail, 74 (54.8%) pre-frail and 26 (19.2%) robust vs 14 (10.4%) frail, 67 (49.6%) pre-frail and 54 (40%) robust (P < .001) in controls. This difference was mainly as a result of decreased muscle strength in patients with cirrhosis. During follow-up, frail patients with cirrhosis showed a higher probability of composite endpoint, hospitalization and falls than pre-frail and robust cirrhotic patients but mortality was similar. MELD-Na score and frailty were independent predictive factors for hospitalization, frailty for falls, and MELD-Na score and albumin for survival. Vitamin D deficiency and increased cystatin C were associated with frailty.

CONCLUSIONS

Frailty was more frequent in outpatients with cirrhosis than in controls, mainly because of a decrease in muscle strength, and it could be a predictive factor for hospitalization and falls in these patients.

Experimental supporting data on the influence of platelet-derived factors of malignant pleural effusions on T cell effector functions and their relevance in predicting prognosis of lung adenocarcinoma patients with pleural metastasis

The data described in this article are supplementary to our primary article “Platelet factor 4 regulates T cell effector functions in malignant pleural effusions”. Malignant pleural effusion (MPE) is a common complication of advanced lung adenocarcinoma (LAC) associated with a poor life expectancy [1]. Several challenges need to be addressed to identify non-invasive molecular biomarkers that help to predict the prognosis of LAC patients with MPE [2]. In the primary publication, we proposed that platelet-derived factors, especially platelet factor 4 (PF4), can negatively regulate T lymphocyte activation and granzyme B expression in pleural metastasis and its levels were associated with a worse prognosis. Here, we provide data on the influence of other platelet-derived factors, including transforming growth factor β (TGF-β), vascular endothelial factor (VEGF), and P-selectin on T lymphocyte response in MPE and their relevance as prognostic factors in lung cancer patients with pleural metastasis. Pleural fluids from 35 lung adenocarcinoma (LAC) and 20 heart failure (HF) patients were collected by thoracentesis and its platelet-derived factors’ content was measured by specific enzyme-linked immunosorbent assay (ELISAs). Correlations between pleural levels of platelet-derived factors and T cell functions were analyzed by Pearson coefficients. Kaplan-Meier curves were used to estimate the effect of pleural concentrations of platelet-derived factors on overall survival of LAC patients with pleural metastasis. These analyses showed that the concentration of platelet-derived factors was not associated with T cell proliferation and cytotoxicity. Furthermore, their levels do not predict the survival of LAC with MPE.

Value of the Data

•

These data provide information about the PF4 production by pleural fluid cells and the association of baseline concentration of PF4 and other platelet-derived factors in pleural fluids with T cell function impairment and overall survival in lung adenocarcinoma patients with MPE.

•

The data provided may be useful for researchers and clinicians that work in the field of pleural metastasis, who are interested in characterizing immune response of the tumor microenvironment and in understanding the relevance of molecular composition of malignant pleural effusions.

•

Our findings can support further research exploring possible sources of plateletderived factors and analyze whether these factors can be used as non-invasive prognostic biomarkers in pleural metastasis derived from other malignancies such breast or ovarian cancer.

Repolarization of tumor infiltrating macrophages and increased survival in mouse primary CNS lymphomas after XPO1 and BTK inhibition

BACKGROUND

Patients diagnosed with primary central nervous system lymphoma (PCNSL) often face dismal outcomes due to the limited availability of therapeutic options. PCNSL cells frequently have deregulated B-cell receptor (BCR) signaling, but clinical responses to its inhibition using ibrutinib have been brief. In this regard, blocking nuclear export by using selinexor, which covalently binds to XPO1, can also inhibit BCR signaling. Selinexor crosses the blood-brain barrier and was recently shown to have clinical activity in a patient with refractory diffuse large B-cell lymphoma in the CNS. We studied selinexor alone or in combination with ibrutinib in pre-clinical mouse models of PCNSL.

METHODS

Orthotopic xenograft models were established by injecting lymphoma cells into the brain parenchyma of athymic mice. Tumor growth was monitored by bioluminescence. Malignant cells and macrophages were studied by immunohistochemistry and flow cytometry.

RESULTS

Selinexor blocked tumor growth and prolonged survival in a bioluminescent mouse model, while its combination with ibrutinib further increased survival. CNS lymphoma in mice was infiltrated by tumor-promoting M2-like macrophages expressing PD-1 and SIRPα. Interestingly, treatment with selinexor and ibrutinib favored an anti-tumoral immune response by shifting polarization toward inflammatory M1-like and diminishing PD-1 and SIRPα expression in the remaining tumor-promoting M2-like macrophages.

CONCLUSIONS

These data highlight the pathogenic role of the innate immune microenvironment in PCNSL and provide pre-clinical evidence for the development of selinexor and ibrutinib as a new promising therapeutic option with cytotoxic and immunomodulatory potential.

Platelet factor 4 regulates T cell effector functions in malignant pleural effusions

Malignant pleural effusion (MPE) is defined as the presence of tumor cells in pleural fluid and it is a fatal complication of advanced lung adenocarcinoma (LAC). To understand the immune response to the tumor in MPE, we compared the concentration of immunomodulatory factors in MPE of LAC and pleural effusion of heart failure (HF) patients by ELISA, and the proliferation and cytotoxic phenotype of T cells stimulated in the presence of LAC and HF pleural fluids by cytometry. Platelet factor 4 (PF4), vascular endothelial growth factor (VEGF), transforming growth factor beta (TGF-β) and P-selectin levels were higher in LAC than in HF pleural fluids. However, plasmatic PF4 and P-selectin levels were similar in LAC and HF. VEGF positively correlated with TGF-β and sPD-L1 in LAC but not in HF pleural fluids. LAC pleural fluids also inhibited T lymphocyte proliferation and cytotoxicity and reduced IL-17 production. PF4 levels inversely correlated with T cell function. The high content of PF4 in MPE was associated with poor prognosis. Our findings suggest that an impaired response of T lymphocytes induced by PF4 provides a significant advantage for tumor progression.

Development of semiquantitative ultrasound scoring system to assess cartilage in rheumatoid arthritis

OBJECTIVES

To develop and test the reliability of a new semiquantitative scoring system for the assessment of cartilage changes by ultrasound in a web-based exercise as well as a patient exercise of patients with RA.

METHODS

A taskforce of the Outcome Measures in Rheumatology Ultrasound Working Group performed a systematic literature review on the US assessment of cartilage in RA, followed by a Delphi survey on cartilage changes and a new semiquantitative US scoring system, and finally a web-based exercise as well as a patient exercise. For the web-based exercise, taskforce members scored a dataset of anonymized static images of MCP joints in RA patients and healthy controls, which also contained duplicate images. Subsequently, 12 taskforce members used the same US to score cartilage in MCP and proximal interphalangeal joints of six patients with RA in in a patient reliability exercise. Percentage agreement and prevalence of lesions were calculated, as intrareader reliability was assessed by weighted kappa and interreader reliability by Light's kappa.

RESULTS

The three-grade semiquantitative scoring system demonstrated excellent intrareader reliability (kappa: 0.87 and 0.83) in the web-based exercise and the patient exercise, respectively. Interreader reliability was good in the web-based exercise (kappa: 0.64) and moderate (kappa: 0.48) in the patient exercise.

CONCLUSION

Our study demonstrates that ultrasound is a reliable tool for evaluating cartilage changes in the MCP joints of patients with RA and supports further development of a new reliable semiquantitative ultrasound scoring system for evaluating cartilage involvement in RA.

Ascitic fluid regulates the local innate immune response of patients with cirrhosis

Ascitic neutrophils from cirrhotic patients with spontaneous bacterial peritonitis (SBP) exhibit an impaired oxidative burst that could facilitate bacterial infection. However, the influence of the cell-free ascitic fluid of these patients on neutrophil function has not been investigated. To analyze this influence, we determined the ascitic levels of cytokines, resistin, and lactoferrin and their association with neutrophil function, disease severity score, and SBP resolution. We analyzed NETosis induction by microscopy and oxidative burst by the flow cytometry of healthy neutrophils cultured in ascitic fluid from cirrhotic patients with sterile ascites (SA) and with SBP before and after antibiotic treatment. Resistin, IL-6, IL-1 receptor antagonist, IL-1β, and lactoferrin levels were measured in ascitic fluids and supernatants of cultured neutrophils and PBMCs by ELISA. Upon stimulation, healthy neutrophils cultured in SBP ascitic fluid produced lower NETosis and oxidative burst than those cultured in SA. Ascitic resistin levels were negatively correlated with NETosis, oxidative burst, and ascitic glucose levels; and positively correlated with the model for end-stage liver disease score. After an E. coli or TNF-α stimulus, neutrophils were the major resistin producers. Resistin indirectly reduced the oxidative burst of neutrophils and directly reduced the inflammatory phenotype of monocytes and TNF-α production. Bacterial-induced resistin production can down-regulate the inflammatory response of macrophages and neutrophil function in ascitic fluid. Consequently, this down-regulation may jeopardize the elimination of bacteria that translocate to ascitic fluid in patients with cirrhosis.

Inverse Association Between Circulating Monocyte-Platelet Complexes and Inflammation in Ulcerative Colitis Patients

BACKGROUND

Circulating monocytes from active ulcerative colitis (UC) patients produced high levels of tumor necrosis factor-alpha(TNFα) and interleukin(IL)-6 after Toll-like receptors (TLR) stimulation. Since platelets (PLT) can bind to leukocytes, thereby decreasing inflammatory cytokine production, UC patients may exhibit different levels of monocyte-platelet complexes depending on disease activity.

METHODS

We compared among healthy donors, active (onset flare and relapse), and inactive UC patients the presence of circulating monocyte-platelet complexes (CD14+PLT+) and membrane CD162 expression by flow cytometry. Lipopolysaccharide- binding protein, TNFα, and IL-10 were compared by ELISA. Binding of CD14+PLT+ to human umbilical vein endothelial cells (HUVECs) were analyzed by immunofluorescence.

RESULTS

Onset flare UC patients had the lowest levels of CD14+PLT+. Membrane CD162, crucial for the PLT binding, was downregulated only on monocytes from onset flare UC patients. Membrane CD162 expression on CD14+ cells inversely correlated with lipopolysaccharide binding protein levels. As an expected consequence, more CD14+PLT+ than CD14+PLT- from onset flare UC patients bound to activated HUVECs. TNFα tended to negatively correlate with CD14+PLT+ in relapse and inactive UC patients, whereas IL-10 positively correlated with CD14+PLT+ in all UC patients (r = -0.43, P = 0.1 and r = 0.61, P = 0.01, respectively). The anti-inflammatory role of PLT binding to monocytes was confirmed in cocultures of PLT and monocytes. These cocultures increased the percentage of CD14+PLT+ and IL-10 production, and decreased TNFα production. These anti-inflammatory effects were abolished when we blocked the binding of PLT with neutralizing anti-CD62P antibody.

CONCLUSIONS

Decreased CD162 expression associated with endotoxemia reduced the binding of PLT to monocytes through membrane CD162-CD62P, favoring the inflammatory response of onset flare UC patients.

Fermented milk containing Lactobacillus paracasei subsp. paracasei CNCM I-1518 reduces bacterial translocation in rats treated with carbon tetrachloride

Probiotics can prevent pathological bacterial translocation by modulating intestinal microbiota and improving the gut barrier. The aim was to evaluate the effect of a fermented milk containing Lactobacillus paracasei subsp. paracasei CNCM I-1518 on bacterial translocation in rats with carbon tetrachloride (CCl₄)-induced cirrhosis. Sprague-Dawley rats treated with CCl₄ were randomized into a probiotic group that received fermented milk containing Lactobacillus paracasei subsp. paracasei CNCM I-1518 in drinking water or a water group that received water only. Laparotomy was performed one week after ascites development. We evaluated bacterial translocation, intestinal microbiota, the intestinal barrier and cytokines in mesenteric lymph nodes and serum. Bacterial translocation decreased and gut dysbiosis improved in the probiotic group compared to the water group. The ileal β-defensin-1 concentration was higher and ileal malondialdehyde levels were lower in the probiotic group than in water group. There were no differences between groups in serum cytokines but TNF-α levels in mesenteric lymph nodes were lower in the probiotic group than in the water group. Fermented milk containing Lactobacillus paracasei subsp. paracasei CNCM I-1518 decreases bacterial translocation, gut dysbiosis and ileal oxidative damage and increases ileal β-defensin-1 expression in rats treated with CCl₄, suggesting an improvement in the intestinal barrier integrity.

Binding of Platelets to Lymphocytes: A Potential Anti-Inflammatory Therapy in Rheumatoid Arthritis

Soluble factors released from platelets can modulate the immune response of leukocytes. We and others have recently found that T lymphocytes with bound platelets have reduced proliferation and IFN-γ and IL-17 production. Thus, we speculate that if we induce the binding of platelets to lymphocytes, we will be able to regulate the inflammatory response. When we cocultured platelets with lymphocytes at different ratios, we were able to increase the percentage of lymphocytes with bound platelets. The coculture of platelets with lymphocytes in the presence of stimulation decreased the production of IFN-γ and TNF-α, T cell proliferation, and the expression of CD25, PD-L1, and SLAM. However, this coculture increased CD39 expression. All of these effects were dependent on the dose of platelets and operated indistinctly with platelets from different healthy donors. When platelets were cocultured in the same compartment with lymphocytes, we observed less IFN-γ and TNF-α production and T lymphocyte proliferation than in cultures with platelets separated from lymphocytes by a 0.4-μm pore size filter. The binding of platelets to lymphocytes was blocked with anti-P-selectin Abs, and when this occurred we observed higher IFN-γ and TNF-α production than in nonblocked conditions. The cocultures of platelets with synovial fluid cells from rheumatoid arthritis patients reduced inflammatory cytokine production and increased IL-10 production. These results suggest that platelet binding to lymphocytes effectively regulates T lymphocyte function. This mechanism could be easily applied to reduce inflammatory responses.

Juvenile, adult and late-onset systemic lupus erythematosus: a long term follow-up study from a geographic and ethnically homogeneous population

OBJECTIVES

This paper aims to identify clinical and serological differences, damage accrual and mortality, in juvenile, adult and late-onset SLE.

METHODS

We conducted our study with patients fulfilling SLE classification criteria taken from the Hospital Gregorio Marañon Autoimmune Systemic Rheumatic Diseases' Registry (1986 to 2012). Clinical characteristics, laboratory data and therapies used during the course of the disease were analysed with patients divided into 3 groups: juvenile-onset (≤ 18 years), adult-onset (19-50) and late onset (>50 years).

RESULTS

Four hundred and forty-five patients were included. Renal disease and cutaneous manifestations were more frequent in the juvenile-onset group at disease onset. During follow-up, juvenile-onset group presented a higher incidence of renal disease, malar rash, Raynaud's phenomenon, cutaneous vasculitis, and neuropsychiatric manifestations than the other two groups. Arthritis and lymphopoenia were more frequent in the adult-onset group. Arterial hypertension and neoplasm were more frequent in the late-onset group. Low serum complement, anti-dsDNA, anti-U1RNP and anti-Sm antibodies were more common in the juvenile-onset group. Patients with late-onset SLE had more damage accrual. Thirty-seven patients (8.3%) died during the study. All-cause mortality was significantly higher in the late-onset group. Age at disease onset >50 years was an independent risk factor for damage accrual (OR, 2.2; 95%CI, 1.1-4.6; p=0.029) and mortality (OR, 2.6; 95%CI, 1.1-6.3; p=0.03).

CONCLUSIONS

We found significant differences in clinical and serological profiles between juvenile, adult and late-onset SLE. The most significant of which was a higher prevalence of neuropsychiatric and renal complications as well as different autoantibody signatures for the juvenile-onset group.

Investigating the link between disease activity and infliximab serum levels in rheumatoid arthritis patients

OBJECTIVES

The aim of this study was to examine the extent to which infliximab (IFX) serum levels impact disease activity in rheumatoid arthritis (RA) patients.

METHODS

In this cross sectional study, serum samples were taken prior to drug infusion from 60 RA patients who had been undergoing IFX therapy > 12 months as a first line of biological treatment. Patient IFX levels were tested and then associated with clinical disease activity. Three DAS28 cut-off points, <2.6, <3.2 and <5.1 were used to determine whether detectable IFX levels were any predictor of clinical disease activity. Logistic regression analysis was run to check other possible factors associated with RA clinical outcomes such as MTX concomitant use, CRP and ESR.

RESULTS

Sixteen (27%) out of the 60 patients tested negative; 28 (46%) presented subtherapeutic and 16 (27%) therapeutic IFX levels. Median IFX levels were higher in patients either in remission or showing low disease activity than in those with moderate and high disease activity (p=0.014). Significant association was found between IFX levels and clinical disease activity (p=0.001). Detectable levels of IFX shows better sensitivity and specificity to identify patients with DAS28<3.2 than to identify patients with DAS28<2.6 or DAS28<5.1. Conversely, the best DAS28 cut-off to identify detectable/undetectable IFX was 3.19, with AUC under ROC curve 0.804 (Sd.E 0.070), 76% specificity and 83% sensitivity (p<0.001). MTX use, CRP and ESR did not interfere with this association. Seven out of the 8 patients with anti-IFX antibodies presented DAS28>3.2 (p=0.005).

CONCLUSIONS

DAS28 and IFX serum levels were shown to have an inverse correlation. Undetectable IFX serum levels were associated to RA patients presenting DAS28>3.2 meaning that DAS28 <3.2 may be useful to clinicians to evaluate patient response to drug therapy.

VSL#3 probiotic treatment decreases bacterial translocation in rats with carbon tetrachloride-induced cirrhosis

BACKGROUND & AIMS

Probiotics can prevent pathological bacterial translocation in cirrhosis by modulating intestinal microbiota and improving gut barrier and immune disturbances. To evaluate the effect of probiotic VSL#3 on bacterial translocation, intestinal microbiota, gut barrier and inflammatory response in rats with experimental cirrhosis.

METHODS

Forty-six Sprague-Dawley rats with CCl4 -induced cirrhosis were randomized into two groups: VSL#3 group (n = 22) that received VSL#3 in drinking water, and water group (n = 24) that received water only. Treatment began at week 6 of cirrhosis induction and continued until laparotomy, performed 1 week after development of ascites or at week 20. A control group included 11 healthy rats. At this study end, we evaluated bacterial translocation, intestinal flora, intestinal barrier (ileal claudin-2 and 4, β-defensin-1, occludin and malondialdehyde as index of oxidative damage) and serum cytokines.

RESULTS

Mortality during this study was similar in the VSL#3 group (10/22, 45%) and the water group (10/24, 42%) (P = 1). The incidence of bacterial translocation was 1/12 (8%) in the VSL#3 group, 7/14 (50%) in the water group (P = 0.03 vs. VSL#3 group) and 0/11 in the control group (P = 0.008 vs. water group). The concentration of ileal and caecal enterobacteria and enterococci was similar in the two groups of cirrhotic rats. The ileal occludin concentration was higher and ileal malondialdehyde and serum levels of TNF-α were lower in the VSL#3 group than in the water group (P < 0.05).

CONCLUSIONS

VSL#3 decreases bacterial translocation, the pro-inflammatory state and ileal oxidative damage and increases ileal occludin expression in rats with experimental cirrhosis.

Adalimumab regulates intracellular TNFα production in patients with rheumatoid arthritis

Introduction

Adalimumab is a fully human anti–tumor necrosis factor α (anti-TNFα) monoclonal antibody that specifically blocks the interaction of TNFα with its receptors. It binds both soluble and transmembrane TNFα. We hypothesized that blocking these TNFα signals regulates the altered TNFα production in rheumatoid arthritis (RA) patients.

Methods

We compared, by flow cytometry, Toll-like receptor induction levels of membrane and intracellular TNFα in monocytes (iTNFα + CD14+ cells) from 12 patients before and after adalimumab treatment with those from 5 healthy donors.

Results

Before starting the treatment, the percentage of iTNFα+ CD14+ cells in the RA patients was significantly lower than that in healthy donors (mean ± SEM = 33.16 ± 4.82% vs 66.51 ± 2.4%, P < 0.001). When we added in vitro TNFα to healthy donor culture cells, levels of iTNFα+ CD14+ cells decreased, suggesting that the TNFα signal was responsible for the iTNFα+ CD14+ cell downregulation observed in the RA patients. After 2, 6 and 12 adalimumab injections, we observed significant blocking of membrane and soluble TNFα and a progressive increase in iTNFα+ CD14+ cells in ten patients with a good to moderate response as defined by the European League Against Rheumatism (EULAR) criteria. Levels of iTNFα+ CD14+ cells after 12 injections in these 10 patients were comparable to levels in healthy donors. In two patients, iTNFα+ CD14+ cell upregulation was not observed, and their EULAR-defined responses had not improved. The first patient developed antiadalimumab antibodies, explaining why adalimumab was not able to block membrane and soluble TNFα. In the second patient, adalimumab was discontinued because of adverse effects, which led to a decrease in iTNFα+ CD14+ cells to levels measured before treatment.

Conclusions

Our findings suggest that adalimumab treatment in RA patients can return iTNFα levels to those of healthy donors. This effect was not observed in the presence of neutralizing antiadalimumab antibodies.

Effects of intravenous albumin in patients with cirrhosis and episodic hepatic encephalopathy: a randomized double-blind study

BACKGROUND & AIMS

Episodic hepatic encephalopathy is frequently precipitated by factors that induce circulatory dysfunction, cause oxidative stress-mediated damage or enhance astrocyte swelling. The administration of albumin could modify these factors and improve the outcome of hepatic encephalopathy. The aim of this study is to assess the efficacy of albumin in a multicenter, prospective, double-blind, controlled trial (ClinicalTrials.gov number, NCT00886925).

METHODS

Cirrhotic patients with an acute episode of hepatic encephalopathy (grade II-IV) were randomized to receive albumin (1.5g/kg on day 1 and 1.0g/kg on day 3) or isotonic saline, in addition to the usual treatment (laxatives, rifaximin 1200mg per day). The primary end point was the proportion of patients in which encephalopathy was resolved on day 4. The secondary end points included survival, length of hospital stay, and biochemical parameters.

RESULTS

Fifty-six patients were randomly assigned to albumin (n=26) or saline (n=30) stratified by the severity of HE. Both groups were comparable regarding to demographic data, liver function, and precipitating factors. The percentage of patients without hepatic encephalopathy at day 4 did not differ between both groups (albumin: 57.7% vs. saline: 53.3%; p>0.05). However, significant differences in survival were found at day 90 (albumin: 69.2% vs. saline: 40.0%; p=0.02).

CONCLUSIONS

Albumin does not improve the resolution of hepatic encephalopathy during hospitalization. However, differences in survival after hospitalization suggest that the development of encephalopathy may identify a subgroup of patients with advanced cirrhosis that may benefit from the administration of albumin.

Functional consequences of platelet binding to T lymphocytes in inflammation

Expression of the scavenger receptor CD36 on lymphocytes is intriguing. We observed that a minor subpopulation of lymphocytes expressed CD36 on the cell surface. We investigated the source of CD36 and also the proliferation and cytokine production of these CD36(+) CD4(+) lymphocytes. Flow cytometry analysis and immunofluorescence microscopy showed that CD36(+) platelets were responsible for CD36 detection on lymphocytes. CD36 was then used as a tool to characterize lymphocytes with bound platelets. Activation-induced proliferation was lower in CD4(+) lymphocytes with bound platelets than lymphocytes without bound platelets. IL-17 and IFN-γ production was also reduced in lymphocytes with bound platelets. We then studied the presence of CD36(+) CD4(+) lymphocytes in RA patients. We observed that the percentage of CD4(+) lymphocytes with bound platelets was higher on RA patients than in healthy donors. RA patients with higher titers of anti-CCP, RF levels, and cardiovascular risk index presented a lower percentage of CD4(+) lymphocytes with bound platelets. These patients also had higher IL-17 and IFN-γ production. These results suggest that platelet-binding modifies lymphocyte function. This binding could be a regulatory mechanism in RA that confers a less severe phenotype.

Characterization of corneal structure in keratoconus

The increasing volume of patients interested in refractive surgery and the new treatment options available for keratoconus have generated a higher interest in achieving a better characterization of this pathology. The ophthalmic devices for corneal analysis and diagnosis have experienced a rapid development during the past decade with the implementation of technologies such as the Placido-disk corneal topography and the introduction of others such as scanning-slit topography, Scheimpflug photography, and optical coherence tomography, which are able to accurately describe not only the geometry of the anterior corneal surface but also that of the posterior surface, as well as pachymetry and corneal volume. Specifically, anterior and posterior corneal elevation, corneal power, pachymetry maps, and corneal coma-like aberrometry data provide sufficient information for an accurate characterization of the cornea to avoid misleading diagnoses of patients and provide appropriate counseling of refractive surgery candidates.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Functional consequences of CD36 downregulation by TLR signals

TLR recognition activates the secretion of pro- and anti-inflammatory cytokines and it also modulates the expression of crucial molecules involved in phagocytosis and antimicrobial activity. Scavenger receptors can act as TLR co-receptors or facilitate antigen loading. However, it remains unknown whether TLR can modulate the expression of these scavenger receptors. We stimulated human peripheral blood mononuclear cells (PBMC) with TLR2 (Pam3CSK4 and FSL1) and TLR4 ligand lipopolysaccharide (LPS) and then analyzed CD36 expression on different monocyte subpopulations by flow cytometry. TLR2 and TLR4 ligands can downregulate CD36 on the surface of monocytes, guiding the protein to intracellular compartments. Even though TLR-activation induced TNFα, IL-10 and IL-6 production, only recombinant TNFα was able to downregulate CD36. Neutralizing anti-TNFα antibodies showed that the Pam3CSK4 and FSL1-induced downregulation was partially mediated by TNFα but not by IL-6 or IL-10. However, LPS-induced downregulation could have also been caused by direct TLR4 targeting and signaling, and/or mediated by other unknown factors. CD36 downregulation reduced the capability of monocytes to phagocyte apoptotic neutrophils. In conclusion, modulation of scavenger receptor expression by TLR targeting on monocytes has functional consequences. Characterization this complex regulation may help us to understand this innate response and develop specific therapeutic drugs for each mechanism.

Selective loss of chemokine receptor expression on leukocytes after cell isolation

Chemokine receptors are distinctively exposed on cells to characterize their migration pattern. However, little is known about factors that may regulate their expression. To determine the optimal conditions for an accurate analysis of chemokine receptors, we compared the expression of CCR2, CCR4, CCR5, CCR6, CXCR3 and CXCR4 on different leukocyte subsets using whole blood (WB) plus erythrocyte lysis and density gradient isolation (Ficoll). Most WB monocytes were CCR2+ (93.5 ± 2.9%) whereas 32.8 ± 6.0% of monocytes from Ficoll-PBMC expressed CCR2 (p<0.001). Significant reductions of CCR6 and CXCR3 on monocytes were also observed after Ficoll isolation (WB: 46.4 ± 7.5% and 57.1 ± 5.5%; Ficoll: 29.5 ± 2.2% and 5.4 ± 4.3% respectively) (p<0.01). Although comparable percentages of WB and Ficoll-PBMC monocytes expressed CCR4, CCR5 and CXCR4, Ficoll isolation significantly reduced the levels of CXCR4 (WB: MFI 5 ± 0.4 and Ficoll: MFI 3.3 ± 0.1) (p<0.05). Similarly to monocytes, CCR2, CXCR3 and CXCR4 were also reduced on lymphocytes. In addition, Ficoll isolation significantly reduced the percentage of CCR4 positive lymphocytes (WB: 90.2 ± 4.5% and Ficoll: 55 ± 4.1%) (p<0.01). The loss of expression of chemokine receptors after isolation of monocytes was not dependent on either the anticoagulant or the density gradient method. It was irreversible and could not be restored by LPS activation or in vitro macrophage differentiation. Experiments tagged with anti-CCR2 antibodies prior to density gradient isolation demonstrated that Ficoll internalized chemokine receptors. The method for cell isolation may alter not only the expression of certain chemokine receptors but also the respective functional migration assay. The final choice to analyze their expression should therefore depend on the receptor to be measured.

Agreement of non-contact pachymetry after LASIK: comparison of combined scanning-slit/Placido disc topography and specular microscopy

PURPOSE

To assess the interchangeability of central corneal thickness (CCT) measurements between combined scanning-slit/Placido disc topography (Orbscan-II) and specular microscopy (Topcon SP-2000P) in patients who underwent laser in situ keratomileusis (LASIK) for myopia.

PATIENTS AND METHODS

We recruited 118 consecutive patients who underwent LASIK for myopia. The CCT was measured using Orbscan-II and Topcon SP-2000P randomly. Orbscan-II and Topcon SP-2000P CCT data were analysed using the paired-sample t-test and the limits of agreement (LoA) were calculated with the method described by Bland-Altman.

RESULTS

The average CCT measurements by Orbscan-II and Topcon SP-2000P were 447.55+/-49.78 microm and 461.38+/-35.35 microm, respectively (P<0.0001; mean difference, 13.83+/-22.31 microm; 95% confidence interval, 9.77-17.09 microm). The Bland-Altman plot showed an inverse association between the average and the difference between the devices: Topcon-Orbscan-II=174.23 -0.353xAverage (P<0.01). The widths of the crude and regression-based 95% limits of agreement were 87.45 and 63.72 microm, respectively.

CONCLUSIONS

Orbscan-II measurements of CCT after myopic LASIK were significantly lower than those obtained using Topcon SP-2000P. The limits of agreement between the two devices were too broad and, therefore, both pachymetric values cannot be used interchangeably. Further, the tendency towards comparably Orbscan-II readings in thinner corneas precludes that one technique can directly replace the other. This is important for the adequate medium- and long-term follow-up of the growing LASIK patient population.

Reliability of noncontact pachymetry after laser in situ keratomileusis

PURPOSE

To assess the repeatability and reproducibility of central corneal thickness (CCT) measurements obtained by combined scanning-slit/Placido-disc topography (Orbscan II; Bausch & Lomb, Rochester, NY) after laser in situ keratomileusis (LASIK) and to compare the results with another noncontact method, specular microscopy (SP-2000P; Topcon, Tokyo, Japan).

METHODS

To analyze intrasession repeatability, one examiner measured 22 postmyopic LASIK eyes 10 times successively in the shortest time possible, using both devices randomly. To study intersession reproducibility, the same operator obtained measurements from another 50 eyes with stable refraction in two consecutive visits at the same time of the day between 6 and 9 months after myopic LASIK. Any association between residual stromal bed thickness and measurement variability was recorded and evaluated.

RESULTS

For intrasession repeatability, Orbscan II and Topcon SP-2000P CCT measurements showed a repeatability of 20.2 (4.3%) and 12.8 (2.6%) microm, respectively. Both devices yielded excellent intraclass correlation coefficients (ICC; 0.98 and 0.99, respectively). For intersession reproducibility, no difference in CCT measurements was found. The coefficient of intersession reproducibility were 6.7% (29.5 microm) for Orbscan II and 4.3% (19.5 microm) for Topcon SP-2000P CCT measurements. The ICCs (0.95 and 0.96, respectively) indicated good intersession reliability. Repeatability and reproducibility with both devices were unrelated to stromal bed thickness.

CONCLUSIONS

Both noncontact pachymeters provide repeatable CCT measurements in transparent postmyopic LASIK corneas after the early postoperative period. Intersession variations in CCT of more than 29 microm with the Orbscan II and 19 microm with the Topcon SP-2000P may reflect true corneal change. These estimates should help investigators and clinicians differentiate actual CCT modification from measurement variability.

Advances in technologies for laser-assisted in situ keratomileusis (LASIK) surgery

Laser-assisted in situ keratomileusis (LASIK) has become the most widely used form of refractive surgery today. The objective of this surgical technique is to modify the anterior corneal shape by ablating tissue from the stroma by means of the excimer laser after creating a hinged corneal flap. This way, we are able to change the refractive status of the patient, providing better unaided vision. Continuous improvements in the original technique have made the surgical procedure safer, more accurate and repeatable. These progressions are due to the development of novel technologies that are the responsible for new surgical instrumentation, which makes the surgical procedure easier for the surgeon, and better excimer laser ablation algorithms, which increase the optical quality of the ablation and thus the safety of the vision correction procedure. This article aims to describe the more relevant advances in LASIK that have played an important role in the spread and popularity of this technique.

Repeatability and Reproducibility of Posterior Corneal Curvature Measurements by Combined Scanning-Slit and Placido-Disc Topography after LASIK

OBJECTIVE

To assess the repeatability and reproducibility of posterior corneal curvature (PCC) measurements made by combined scanning-slit/Placido-disc topography (Orbscan II) after LASIK.

DESIGN

Experimental instrument validation study.

PARTICIPANTS

We recruited 22 consecutive postmyopic LASIK patients for the repeatability study and another 50 consecutive postmyopic LASIK patients for the reproducibility study.

METHODS

To analyze intrasession repeatability, 1 examiner measured 22 postmyopic LASIK eyes 10 times successively in the shortest time possible. To study intersession reproducibility, the same operator obtained measurements from another 50 eyes with stable refraction in 2 consecutive visits at the same time of the day between 6 and 9 months after myopic LASIK. We explored any association between residual stromal bed thickness and measurement variability.

MAIN OUTCOME MEASURES

Orbscan II scanning-slit PCC data, precision, within-subject coefficient of variation (CV(w)), limits of agreement (LoA), and intraclass correlation coefficient (ICC).

RESULTS

For intrasession repeatability, precision was 0.067 mm (best-fit sphere [BFS]), 0.110 diopters (D; power within 5 mm), 0.158 D (power within 3 mm), and 0.46 (eccentricity). Repeatability was high for PCC BFS and power measurements within 3-mm and 5-mm zones (CV(w) ranged from 0.5%-1.2%) but poor for eccentricity data (CV(w), 31.6%). Correspondingly, ICCs ranged from 0.89 to 0.98 for PCC BFS and power, and the ICC was 0.20 for PCC eccentricity values. For intersession reproducibility, on average, no difference in PCC measurements could be found, indicating that when there is variability, it is due to random factors. The width of the 95% LoA between sessions was clinically acceptable for BFS (0.25 mm) and power (0.4 D [within 5 mm] and 0.6 D [within 3 mm]). Similarly, ICCs indicated good intersession reliability for BFS and power (0.98, 0.96, and 0.85 for BFS, power within 5 mm, and power within 3 mm, respectively) but poor reliability for eccentricity (0.59). Repeatability and reproducibility were unrelated to stromal bed thickness.

CONCLUSIONS

Orbscan II provides reliable post-LASIK PCC data for symmetrical parameters (BFS and power), independent of the residual stromal bed thickness, but is unreliable for measurements that are radially asymmetrical (eccentricity). Orbscan II is useful for monitoring the PCC after LASIK once the early postoperative period is over.

Posterior Corneal Curvature Changes after Undersurface Ablation of the Flap and In-the-Bed LASIK Retreatment

OBJECTIVE

To analyze LASIK retreatment-induced changes in the posterior corneal curvature (PCC) with undersurface ablation of the flap (UAF) and in-the-bed techniques.

DESIGN

Nonrandomized, comparative, interventional study.

PARTICIPANTS

Forty-six eyes with a residual spherical equivalent refraction between -0.37 and -2.75 diopters (D) and astigmatism between 0.0 and -1.25 D were included prospectively. In 23 eyes, the calculated postenhancement flap thickness exceeded 150 microm using micropachymetric optical coherence tomography, whereas with further ablation of the bed, the residual bed thickness (RBT) would have been <250 microm, or <55% of the pre-LASIK central pachymetry. In another 23 eyes, RBT allowed the planned ablation for a calculated post-retreatment RBT exceeding 250 microm, >55% of the pre-LASIK central pachymetry.

INTERVENTION

Eyes with insufficient RBT for further ablation underwent UAF retreatment, whereas those with adequate RBT received conventional in-the-bed LASIK retreatment. Examinations were performed before retreatment and 3 and 6 months postoperatively. No eye was lost to follow-up.

MAIN OUTCOME MEASURES

Micropachymetry, Orbscan II scanning-slit PCC data, and visual acuity (VA).

RESULTS

The groups did not differ in age, intraocular pressure, or retreatment ablation depth, but the UAF eyes had a lower mean pre-retreatment RBT (270.7+/-25.4 microm) than conventional enhancement eyes (353.0+/-41.5 microm) (P = 0.001). Eyes undergoing UAF had no significant change in PCC, whereas eyes undergoing conventional retreatment had an increase in the posterior corneal power within the central 3-mm zone (P = 0.008) 3 months after retreatment. No significant changes occurred thereafter. The amount of change in posterior corneal power within the 3-mm central zone from before to after retreatment differed significantly between the groups (mean difference, 0.135 D; 95% confidence interval, 0.022-0.248 D; P = 0.02). No keratectasia developed clinically, and no retreated eye lost or gained > or =2 lines of best-corrected VA. Six months after retreatment, the efficacy and safety indices for the UAF procedure were 0.96 and 1.01, respectively, and 1 and 1.06 for conventional LASIK enhancement.

CONCLUSION

Undersurface ablation of the flap retreatment appears to have less potential for changing the posterior corneal surface than conventional LASIK enhancement and can help reduce the likelihood of retreatment-induced keratectasia.

Primary trochlear headache

BACKGROUND

The authors have observed a group of patients complaining of periorbital pain, emanating from the trochlear area, in absence of trochleitis or other orbital or systemic disease. All were previously diagnosed and treated as different types of headaches, but pain was not controlled until local treatment on the sore trochlea was performed. The authors have investigated the role of the trochlear area in causing and modulating headache.

METHODS

Observational case series. Trochlear pain was defined as pain on this area, exacerbated upon examination and looking in supraduction. Pain was studied after trochlear injections of lidocaine, corticosteroids, and placebo. Secondary orbital pain was ruled out.

RESULTS

Seventeen women and one man were evaluated (mean age: 44 years). All presented unilateral pain in the trochlear area (60% reported more extended headache), for more than 1 year in 70%. Neither ocular autonomic signs nor motility restrictions were observed. Imaging examinations were normal in 100%. The temporal pattern was either chronic or remitting, with acute exacerbations. Pain increased at night in 55%. A total of 62% presented concurrent headaches. Locally injected corticosteroids relieved the pain within 48 hours in 95% and also improved concurrent headaches, by decreasing attack frequency and analgesics intake. Placebo was not helpful. Relapses were observed in 45% (average 8 months).

CONCLUSIONS

The trochlear region is the origin of a specific and unrecognized headache, which we have named primary trochlear headache. Local treatment on the trochlear area is also useful for other concurrent primary headaches with inadequate response to oral therapy.

Depressive disorders in epilepsy

Depression is a common occurrence among epileptic patients and constitutes, along with anxiety disorders, the most frequent psychiatric condition in these patients. The relationship between depression and epilepsy is two-directional, because patients with major depression also have a higher frequency of epilepsy. In epileptic patients, depressive disorders can present as unipolar, bipolar, or dysthymic disorders. More characteristically, however, they present as an atypical depression, which can often go unrecognized for long periods of time. In the diagnostic evaluation of these patients, clinicians must rule out the possibility that the depressive disorder resulted from the administration of antiepileptic drugs (AEDs; e.g., barbiturates) or from the discontinuation of an AED with mood-stabilizing properties that were masking an underlying affective disorder. Although antidepressant drugs have been used in epileptic patients for a long time, to date there has only been one controlled study. The antidepressants of the family of selective serotonin reuptake inhibitors (SSRIs) should be considered as initial therapy for depressive disorders in these patients.

Characterization and selection of lactobacilli isolated from Spanish fermented sausages

The use of starter cultures to control and run the fermentative process is a usual way of manufacturing sausages in meat industries. The first stage in the starter culture designing process is to characterize the lactic acid bacteria isolated from these meat products, in order to select the best strains. The strains used for this study were isolated from different dry fermented sausages, obtained during the manufacturing process. The main tests used to identify the isolated bacteria were: microscopic-morphologic characteristics, catalase activity, production of gas, growth at 8, 15 and 45 degrees C, fermentation of carbohydrates and production of lactic acid isomers. A total of 194 strains were identified. Lactobacillus sake and Lactobacillus plantarum were the most frequent species. Other microbiological tests were also performed, and three strains of Lactobacillus sake were found which did not produce dextran from sucrose.