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1.
Biomedicines ; 10(5)2022 May 11.
Article in English | MEDLINE | ID: mdl-35625847

ABSTRACT

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) are commonly treated with inhaled corticosteroid/long-acting ß2-agonist combination therapy. While previous studies have investigated the host-microbiome interactions in COPD, the effects of specific steroid formulations on this complex cross-talk remain obscure. METHODS: We collected and evaluated data from the Study to Investigate the Differential Effects of Inhaled Symbicort and Advair on Lung Microbiota (DISARM), a randomized controlled trial. Bronchoscopy was performed on COPD patients before and after treatment with salmeterol/fluticasone, formoterol/budesonide or formoterol-only. Bronchial brush samples were processed for microbial 16S rRNA gene sequencing and host mRNA sequencing. Longitudinal changes in the microbiome at a community, phylum and genus level were correlated with changes in host gene expression using a Spearman's rank correlation test. FINDINGS: In COPD patients treated with salmeterol/fluticasone, the expression levels of 676 host genes were significantly correlated to changes in the alpha diversity of the small airways. At a genus level, the expression levels of 122 host genes were significantly related to changes in the relative abundance of Haemophilus. Gene enrichment analyses revealed the enrichment of pathways and biological processes related to innate and adaptive immunity and inflammation. None of these changes were evident in patients treated with formoterol/budesonide or formoterol alone. INTERPRETATION: Changes in the microbiome following salmeterol/fluticasone treatment are related to alterations in the host transcriptome in the small airways of patients with COPD. These data may provide insights into why some COPD patients treated with inhaled corticosteroids may be at an increased risk for airway infection, including pneumonia. FUNDING: The Canadian Institute of Health Research, the British Columbia Lung Association, and an investigator-initiated grant from AstraZeneca.

2.
Front Immunol ; 12: 628453, 2021.
Article in English | MEDLINE | ID: mdl-33659009

ABSTRACT

The microbiome plays a fundamental role in how the immune system develops and how inflammatory responses are shaped and regulated. The "gut-lung axis" is a relatively new term that highlights a crucial biological crosstalk between the intestinal microbiome and lung. A growing body of literature suggests that dysbiosis, perturbation of the gut microbiome, is a driving force behind the development, and severity of allergic asthma. Animal models have given researchers new insights into how gut microbe-derived components and metabolites, such as short-chain fatty acids (SCFAs), influence the development of asthma. While the full understanding of how SCFAs influence allergic airway disease remains obscure, a recurring theme of epigenetic regulation of gene expression in several immune cell compartments is emerging. This review will address our current understanding of how SCFAs, and specifically butyrate, orchestrates cell behavior, and epigenetic changes and will provide a detailed overview of the effects of these modifications on immune cells in the context of allergic airway disease.


Subject(s)
Asthma/metabolism , Bacteria/metabolism , Butyrates/metabolism , Eosinophils/metabolism , Gastrointestinal Microbiome , Lung/metabolism , Lymphocytes/metabolism , Mast Cells/metabolism , Animals , Asthma/immunology , Asthma/microbiology , Asthma/physiopathology , Dysbiosis , Eosinophils/immunology , Humans , Lung/immunology , Lung/physiopathology , Lymphocytes/immunology , Mast Cells/immunology , Phenotype , Signal Transduction
3.
Curr Pharm Des ; 25(43): 4560-4569, 2020.
Article in English | MEDLINE | ID: mdl-31820696

ABSTRACT

Neurofilaments: light, medium, and heavy (abbreviated as NF-L, NF-M, and NF-H, respectively), which belong to Type IV intermediate filament family (IF), are neuron-specific cytoskeletal components. Neurofilaments are axonal structural components and integral components of synapses, which are important for neuronal electric signal transmissions along the axons and post-translational modification. Abnormal assembly of neurofilaments is found in several human neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS), infantile spinal muscular atrophy (SMA), and hereditary sensory-motor neuropathy (HSMN). In addition, those pathological neurofilament accumulations are known in α-synuclein in Parkinson's disease (PD), Aß and tau in Alzheimer's disease (AD), polyglutamine in CAG trinucleotide repeat disorders, superoxide dismutase 1 (SOD1), TAR DNA-binding protein 43 (TDP43), neuronal FUS proteins, optineurin (OPTN), ubiquilin 2 (UBQLN2), and dipeptide repeat protein (DRP) in amyotrophic lateral sclerosis (ALS). When axon damage occurs in central nervous disorders, neurofilament proteins are released and delivered into cerebrospinal fluid (CSF), which are then circulated into blood. New quantitative analyses and assay techniques are well-developed for the detection of neurofilament proteins, particularly NF-L and the phosphorylated NF-H (pNF-H) in CSF and serum. This review discusses the potential of using peripheral blood NF quantities and evaluating the severity of damage in the nervous system. Intermediate filaments could be promising biomarkers for evaluating disease progression in different nervous system disorders.


Subject(s)
Neurodegenerative Diseases/diagnosis , Neurofilament Proteins/blood , Biomarkers/blood , Humans , Prognosis
4.
Oncol Rep ; 24(4): 949-55, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20811675

ABSTRACT

In this study, we investigated the expression of 14-3-3sigma tumor suppressor gene in a panel of NPC cell lines, xenografts and primary tumors. Our objective was to determine the correlation between 14-3-3sigma expression and clinical outcome in NPC. We detected reduced 14-3-3sigma expression in 5/6 NPC tumor lines by quantitative RT-PCR and Western blotting. By immunohistochemical staining, significant down-regulation of 14-3-3sigma was also found in 26/72 (36.1%) primary tumors of NPC patients, who were treated with curative radiotherapy. Promoter methylation was confirmed in a subset of primary tumors by methylation-specific PCR analysis. Importantly, we demonstrated that 14-3-3sigma expression is significantly associated with both overall survival (OS) and cancer-specific survival (CSS), but not with the clinical staging of NPC patients. The low 14-3-3sigma expression was associated with improved overall (p=0.029) and cancer-specific survival (p=0.042) on univariate analysis. 14-3-3sigma expression and staging were also independent variables to all the prognostic factors under multivariate analysis. In conclusion, low expression of 14-3-3sigma appears to be a valuable marker for better survival in patient with NPC. These results provide the evidence that 14-3-3sigma expression is a significant prognostic factor for NPC patients.


Subject(s)
14-3-3 Proteins/biosynthesis , Biomarkers, Tumor/analysis , Carcinoma/metabolism , Exonucleases/biosynthesis , Adult , Aged , Aged, 80 and over , Animals , Biomarkers, Tumor/biosynthesis , Blotting, Western , Carcinoma/mortality , Carcinoma/pathology , DNA Methylation , Exoribonucleases , Female , Gene Expression , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Male , Middle Aged , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms/metabolism , Nasopharyngeal Neoplasms/mortality , Nasopharyngeal Neoplasms/pathology , Neoplasm Staging , Prognosis , Promoter Regions, Genetic/genetics , Reverse Transcriptase Polymerase Chain Reaction , Xenograft Model Antitumor Assays , Young Adult
5.
Ann Acad Med Singap ; 39(5): 390-3, 2010 May.
Article in English | MEDLINE | ID: mdl-20535430

ABSTRACT

INTRODUCTION: The device closure of atrial septal defects has evolved over the years. In the early days of transcatheter occlusion, balloon sizing was used to choose an appropriate sized device. We postulate that balloon sizing does not value-add to the procedure and is unnecessary. MATERIALS AND METHODS: Patients who had balloon sizing, with (Group 1, n = 38) or without (Group 2, n = 21) atrial septal defect closure, were compared to another group (Group 3, n = 64) who had atrial septal defect closure without balloon sizing. Although the atrial septal defect size (mm) in those without balloon sizing (Group 3) compared to patients who had balloon sizing (Group 1) (18.3 +/- 5.4 vs 14.8 +/- 5.8; P = 0.021) was larger, the Amplatzer septal occluder size chosen (mm) (21.6 +/- 6.3 vs 21.2 +/- 8.1; P = 0.693) was similar. RESULTS: We analysed the degree of absolute sizing, defined as [(Balloon or Amplatzer occluder size) - (transoesophageal echocardiography size)], versus relative sizing, which is defined as [(Balloon or Amplatzer occluder size)--(transoesophageal echocardiography size) / (Balloon or Amplatzer occluder size)]. It was evident that there was greater absolute and relative over-sizing (6.3 +/- 4.4 mm vs 4.2 +/- 2.1 mm; P = 0.009 and 28.3 +/- 15.4% vs 20.0 +/- 7.0%; P = 0.001, respectively) in patients with balloon sizing (Group 1) compared to those who did not (Group 3). Even a greater degree of absolute (5.1 +/- 3.9 mm vs 9.5 +/- 4.7 mm; P <0.001) and relative over-sizing (24.8 +/- 15.6% vs 33.0 +/- 13.6%; P = 0.001) was observed in patients who had balloon sizing but there was no closure (Group 2) compared to those who had balloon sizing and closure of their defects (Group 1). CONCLUSION: Our results showed that balloon sizing tended to over-size the atrial septal defect. This may have an important bearing in selecting a larger device than necessary, or even precluding transcatheter closure of the larger atrial septal defects. It is also associated with increased procedural, fluoroscopy time and cost. We suggest that balloon sizing may no longer be necessary in the protocol of device closure of an atrial septal defect.


Subject(s)
Cardiac Catheterization/instrumentation , Echocardiography, Transesophageal , Heart Septal Defects, Atrial/diagnostic imaging , Heart Septal Defects, Atrial/surgery , Septal Occluder Device , Adolescent , Adult , Aged , Cardiac Catheterization/methods , Child , Child, Preschool , Female , Heart Septal Defects, Atrial/pathology , Humans , Male , Middle Aged , Young Adult
6.
J Invasive Cardiol ; 21(12): 623-6, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19966363

ABSTRACT

OBJECTIVE: We devised a new technique for interventional closure of atrial septal defect (ASD) using the Amplatzer Septal Occluder (ASO), and validated this by comparing it with a cohort using the conventional method. BACKGROUND: Transcatheter closure of ASD is a widely accepted modality of treatment. Although the outcome is good, there are occasional technical difficulties encountered. METHOD: In this three-step technique, the device is protruded to form a "tulip bud." This "tulip bud" is then aligned adjacent to and along the plane of the ASD. The second step involves withdrawing the sheath in quick succession to deploy atrial discs over the septal defect. Finally, good placement of the occluder is checked before release. RESULTS: Twenty-seven consecutive patients (1.4-77.2 years of age, median = 15) underwent device closure by this method. Nineteen (70.4%) had a deficient aortic rim (< 5 mm). Mean (+/- SD) ASD size by transesophageal echocardiography (TEE) was 16.0 +/- 5.1 mm. The chosen ASO size was 122 +/- 8% of the ASD size. The mean (+/- SD) duration of deployment and of deployment to release was 1.27 +/- 1.91 minutes and 5.18 +/- 2.63 minutes, respectively. The total fluoroscopy and procedure time was 9.93 +/- 5.61 minutes and 68.67 +/- 28.39 minutes, respectively. Twenty-one out of 27 patients (77.8%) had closure in one attempt. Comparing these 27 patients with the previous 48 consecutive patients with a deficient aortic rim by the conventional method, there was no difference in age, body weight, Qp/Qs, ASD size and ASO size or degree of oversizing (p > 0.05). The percentage of patients with aortic root deficiency was slightly higher in "tulip-bud" group compared to the conventional group (63.2% vs. 58.4%; p = 0.039). No complications were observed in either series. CONCLUSION: This is a promising new method to circumvent some of the difficulties associated with closure of large ASDs and deficient aortic rim.


Subject(s)
Cardiovascular Surgical Procedures/methods , Heart Septal Defects, Atrial/surgery , Septal Occluder Device , Adolescent , Adult , Aged , Cardiac Catheterization/methods , Cardiovascular Surgical Procedures/adverse effects , Cardiovascular Surgical Procedures/instrumentation , Child , Child, Preschool , Echocardiography, Transesophageal , Female , Fluoroscopy , Heart Septal Defects, Atrial/diagnostic imaging , Humans , Infant , Male , Middle Aged , Reproducibility of Results , Septal Occluder Device/adverse effects , Treatment Outcome , Young Adult
7.
Ann Acad Med Singap ; 38(3): 181-3, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19347068
8.
Hepatology ; 45(4): 977-81, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17393507

ABSTRACT

UNLABELLED: Primary biliary cirrhosis (PBC) recurs in the allograft after liver transplantation. Study of early tissue changes in the time-course of disease recurrence provides a unique insight into the initial stages of the disease process, which, in nontransplant patients, occurs long before clinical presentation. We describe a patient who developed classical clinical, biochemical, immunological, and histological features of PBC within 9 months after transplantation. Use of tissue from this patient before and during the development of PBC allowed us to identify biliary epithelial cell (BEC) epithelial-mesenchymal transition (EMT) as a key pathogenetic process. BEC expression of S100A4 (an early fibroblast lineage marker established as a robust marker of EMT), vimentin, and pSmad 2/3 [a marker of transforming growth factor beta (TGF-beta) pathway signaling] were identified immunohistochemically in most BECs in liver tissue from this patient at the point of diagnosis of recurrent disease. BEC expression of S100A4 and pSmad 2/3 was seen as early as 24 days after orthotopic liver transplantation (OLT), although no other features of recurrent PBC were present at this time. CONCLUSION: S100A4, vimentin, and pSmad 2/3 expression in early recurrent PBC after OLT suggests that BEC EMT is occurring (potentially explaining BEC loss) and that this process is driven by TGF-beta. S100A4 expression by BEC appears to occur before the development of any other features of recurrent PBC, suggesting that EMT may be an initiating event.


Subject(s)
Epithelial Cells/pathology , Fibroblasts/pathology , Liver Cirrhosis, Biliary/pathology , Liver Transplantation , Liver/pathology , Adult , Biomarkers/metabolism , Epithelial Cells/metabolism , Female , Fibroblasts/metabolism , Humans , Immunohistochemistry , Liver/metabolism , Liver Cirrhosis, Biliary/metabolism , Recurrence
10.
Semin Diagn Pathol ; 23(3-4): 149-60, 2006.
Article in English | MEDLINE | ID: mdl-17355088

ABSTRACT

Alcohol excess is associated with a spectrum of disease ranging from simple steatosis through steatohepatitis to cirrhosis and, in some, hepatocellular carcinoma. Alcoholic steatohepatitis itself has a variable histological picture, but a constant feature is the presence of ballooning degeneration of hepatocytes. Recent studies have emphasized the importance of apoptosis as a mechanism of cell death in this condition. It is accompanied by varying degrees of perivenular, centrilobular, and pericellular fibrosis. When severe and associated with perivenular liver cell necrosis (central sclerosing hyaline necrosis), there may be precirrhotic portal hypertension. The pattern of fibrosis may initially be diffuse with little nodule formation, but in time there is frequently the development of a micronodular cirrhosis. In approximately 15% of patients with established cirrhosis, hepatocellular carcinoma develops; several precursor lesions are now recognized which can be detected histologically. Several authors have drawn attention to additional components of the spectrum of alcoholic liver disease, including vascular changes, portal tract inflammation and fibrosis, ductular reaction, and iron overload. The morphology of alcoholic liver disease can be significantly affected by abstinence; furthermore, the clinical and morphological phenotype can be significantly influenced by the presence of comorbid conditions such as nonalcoholic fatty liver disease or viral hepatitis. Biopsy appearances can provide important prognostic information in alcoholic liver disease, and this review incorporates a proposed grading and staging schema for assessment of histological severity.


Subject(s)
Liver Diseases, Alcoholic/pathology , Comorbidity , Diagnosis, Differential , Fatty Liver/pathology , Humans
11.
Catheter Cardiovasc Interv ; 66(3): 436-41, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16216027

ABSTRACT

Two patients with perimembranous ventricular septal defects (VSDs) and inlet extension have undergone uncomplicated transcatheter device closure using the Amplatzer membranous VSD device. Both patients developed complete heart block 2-4 days from the closure. Both patients responded well to high-dose intravenous therapy with steroids and high-dose oral anti-inflammatory aspirin. Both patients remain in normal sinus rhythm 8 weeks and 10 months, respectively, from the episode.


Subject(s)
Aspirin/therapeutic use , Cardiac Catheterization/adverse effects , Cardiac Surgical Procedures/adverse effects , Glucocorticoids/therapeutic use , Heart Block/etiology , Heart Septal Defects, Ventricular/surgery , Platelet Aggregation Inhibitors/therapeutic use , Cardiac Surgical Procedures/methods , Child, Preschool , Drug Therapy, Combination , Electrocardiography , Female , Heart Block/drug therapy , Heart Block/physiopathology , Heart Rate/physiology , Humans , Infant
12.
Prenat Diagn ; 25(7): 546-52, 2005 Jul.
Article in English | MEDLINE | ID: mdl-16032763

ABSTRACT

OBJECTIVES: To evaluate the fetal cardiac time intervals from the longitudinal analysis of noninvasive fetal electrocardiography (fECG) in normal pregnancies. METHODS: One hundred singleton pregnancies were examined in this longitudinal study. Cardiac time intervals were derived from fetal electrocardiograms obtained noninvasively using three electrodes placed on the maternal abdomen. The variables measured included the durations of the P wave, PR interval, QRS complex, QT interval and T wave. RESULTS: Success rates for detecting the P, QRS and T waves were 74.6, 91.0 and 79.3%, respectively. Cardiac time intervals were significantly influenced by fetal age. The mean P-wave duration increased from 43.9 (18--22 weeks) to 52.9 ms (>/=37 weeks) (p < 0.001). PR intervals were 102.1 and 110.1 ms, for fetuses at 18 to 22 and >/=37 weeks (p < 0.001), respectively. QRS intervals were 47.2 and 52.6 ms (p < 0.001), while QT intervals were 224.0 and 242.7 ms (p < 0.001), at 18 to 22 and >/=37 weeks respectively. From 18 to 22 weeks to >/=37 weeks, QT(c) values increased from 343.8 to 367.7 ms (p < 0.001), while T-wave durations increased from 123.8 to 152.4 ms (p < 0.001). CONCLUSIONS: Serial noninvasive fECG of normal fetuses from 18 to 41 weeks of gestation show good success rates of fECG detection. Cardiac time intervals generally increased with increasing gestational age.


Subject(s)
Arrhythmias, Cardiac/diagnosis , Electrocardiography/methods , Heart Rate, Fetal/physiology , Arrhythmias, Cardiac/embryology , Arrhythmias, Cardiac/physiopathology , Cardiotocography/methods , Female , Gestational Age , Humans , Longitudinal Studies , Predictive Value of Tests , Pregnancy
14.
J Perinat Med ; 32(6): 532-4, 2004.
Article in English | MEDLINE | ID: mdl-15576277

ABSTRACT

We document the value of non-invasive fetal electrocardiography (fECG) in a case of fetal arrhythmia in which an unnecessary cesarean section was almost performed. The fetal heart rate (fHR) was 60-70 beats per minute (bpm) on the cardiotocography (CTG), with occasional, sudden fluctuations to 130 bpm. This was probably a result of the technical limitations of the CTG.


Subject(s)
Cardiotocography , Ventricular Premature Complexes/diagnosis , Adolescent , Bradycardia/congenital , Bradycardia/diagnosis , Bradycardia/physiopathology , Diagnosis, Differential , Female , Humans , Infant, Newborn , Male , Pregnancy , Ventricular Premature Complexes/congenital , Ventricular Premature Complexes/physiopathology
15.
Laryngoscope ; 113(5): 843-7, 2003 May.
Article in English | MEDLINE | ID: mdl-12792320

ABSTRACT

OBJECTIVE: To investigate whether autologous ossicles can be safely used in ossicular reconstruction in cholesteatoma surgery after attempting cholesteatoma removal under the operating microscope. STUDY DESIGN: A prospective fine-section histological study of formalin-stored ossicles, harvested from cholesteatomatous ears, to evaluate for existence of residual cholesteatoma after surface disease clearance under the operating microscope. METHODS: One hundred four ossicles were harvested from 76 patients with cholesteatoma for the study. These malleus heads and includes were categorized into three groups: group 1, ossicles with retained shape and useful bulk, treated by microscopic stripping alone; group 2, ossicles with retained shape and useful bulk, treated by microscopic stripping and drilling; and group 3, badly eroded ossicles, treated by microscopic stripping alone. These treated ossicles were then subjected to 4 microm histopathological study. RESULTS: Residual disease was identified in 6 of the 104 ossicles. Residual disease was found only in badly eroded ossicles that are not suitable for reconstruction. All the usable ossicles were free of disease. CONCLUSIONS: Autologous ossicles that have retained body and bulk are safe to use for reconstruction after surface stripping under the operating microscope. Additional burring probably adds a further margin of safety.


Subject(s)
Cholesteatoma, Middle Ear/surgery , Ossicular Replacement , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Cholesteatoma, Middle Ear/pathology , Culture Techniques , Feasibility Studies , Female , Humans , Male , Malleus/surgery , Mastoid/surgery , Middle Aged , Prospective Studies , Transplantation, Autologous
16.
Arch Pathol Lab Med ; 127(7): 872-5, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12823046

ABSTRACT

We report an unusual case of ependymoma with pigmentation, a phenomenon that has only been described in a few cases, to our knowledge. This tumor occurred in the fourth ventricle of a 45-year-old man. It showed the typical histologic appearance of ependymoma with perivascular pseudorosettes and rare ependymal rosettes. Some tumor cells contained brown cytoplasmic pigment, which was shown histochemically to represent a mixture of lipofuscin and neuromelanin. The pigment was positive for acid-fast and periodic acid-Schiff stains and was also focally positive for Masson-Fontana and Schmorl stains (bleached by pretreatment with potassium permanganate). In addition, some other tumor cells showed a signet ring morphology as a result of prominent intracytoplasmic vacuolation. Immunohistochemically, all the tumor cells expressed glial fibrillary acidic protein, and rare pigmented tumor cells also expressed HMB-45. Ultrastructural examination showed irregularly shaped heterogeneous electron-dense bodies corresponding to the pigment, and the cytoplasmic vacuoles were formed by dilatation of intracytoplasmic lumens lined by microvilli. Since lipofuscin production can occur in normal ependymal cells and neuromelanin has been suggested to be a melanized form of lipofuscin, it is not surprising that these 2 pigments can be found in ependymoma. In all the previously reported cases, the pigment was shown to represent melanin only. In our case, the HMB-45 positivity in rare tumor cells indicated that there might also be a minor melanin component in the pigment in addition to lipofuscin and neuromelanin.


Subject(s)
Cerebellar Neoplasms/diagnosis , Ependymoma/diagnosis , Lipofuscin/biosynthesis , Melanins/biosynthesis , Cerebellar Neoplasms/chemistry , Cerebellar Neoplasms/radiotherapy , Cerebellar Neoplasms/surgery , Ependymoma/chemistry , Ependymoma/radiotherapy , Ependymoma/surgery , Humans , Male , Middle Aged
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