Causes and prevalence of inadequate pulmonary function testing among patients with systemic sclerosis

Introduction

Spirometry is a screening tool for evaluating the degree of restrictive lung disease in systemic sclerosis (SSc). Observations indicated that some patients could not complete the test. The aim of the study was to identify the prevalence, causes and clinical predictors of an inadequate pulmonary function test (PFT) in SSc.

Material and methods

A cross-sectional study was performed among SSc patients over 18 years old followed up at Srinagarind Hospital, Khon Kaen, Thailand, during January 2006–December 2012. The adequacy of the PFT was based on the acceptable blow criteria as set out by the American Thoracic Society and the European Respiratory Society 2005 Standardizations of Spirometry.

Results

Two hundred and forty-nine patients were included (female to male ratio was 2 : 1). The mean age at performing PFT was 51.4 ±11.1 years (range: 19.6–79.5). Median duration of disease at performing PFT was 2 years (IQR: 0.6–4.4). Inadequate PFT occurred in 73 cases (prevalence 29.3%: 95% CI: 23.6–35.0); the majority (60 cases; 82.2%) had an expiration time < 6 s and the others were due to plateau < 1 s (11 cases; 15%), air leak around mouth piece (1 case; 1.4%) and hesitation (1 case; 1.4%). Thirteen of 73 (17.8%) had an unusable graph with the overall prevalence of 5.2% (95% CI: 2.4–8.0). The factor associated with inadequate PFT was docy mass index (BMI) < 18.5 kg/m² (OR = 2.17: 95% CI: 1.49–3.17); the same factor was associated with an unusable graph, which was confirmed by the multivariate analysis (OR = 5.21; 95% CI: 1.60–16.95).

Conclusions

One-third of Thai SSc patients had an inadequate pulmonary function test – the majority because of inadequate time for expiring. Low BMI influenced the effectiveness of the test, leading to an incomplete graph for evaluating lung disease in SSc.     

A simplified screening for alpha-thalassemia 1 (SEA type) using a combination of a modified osmotic fragility test and a direct PCR on whole blood cell lysates

In order to provide a rapid method for identifying alpha-thalassemia 1 in a region with massive population and limited resources, we have tested a rapid screening strategy. Preliminary screening was done using a modified one tube osmotic fragility test (OF test) followed by RBC indices; Hb analysis and detection of alpha-thalassemia 1 with the Southeast Asian deletion (SEA type) were performed by PCR. One hundred and seventy-five adult Thai subjects were studied. Fifty-one of the 175 subjects (29.1%) were positive for a modified OF test. They all had significantly lower MCV and MCH but higher RDW-CV values as compared to the OF negative group. A successful identification of alpha-thalassemia 1 deletion using a direct PCR on cell lysates was demonstrated. Among the 51 OF-test-positive subjects, 7 were found to be alpha-thalassemia 1 carriers, 3 of whom were also carriers of Hb E. No alpha-thalassemia 1 was detected in the OF-test-negative group. A combination of a modified OF test and a direct PCR analysis on whole blood cell lysates would therefore provide an effective screening for alpha-thalassemia 1 in the regions where a program of prevention and control of the disease remains underserved.     

The toxicity of betel nut extract determined by inhibition of microbial dehydrogenase activity

Dimethyl sulfoxide extracts of betel nut (100g/L) and betel leaf (100g/L), and methanol and water extracts of betel nut (100g/L) were found to inhibit dehydrogenase activity of Bacillus subtilis. In contrast betel nut (100g/L) extracted by petroleum ether showed no inhibitory effect. Thin layer chromatography, ultraviolet spectroscopy and total polyphenols estimation indicated that betel nut contained large amounts of polyphenols. On the basis of toxicity assessment, the results implied that betel nuts and betel leaves contained a hydrophilic element which was toxic to living cells.     

Lack of associations between thyroid function and obstructive sleep apnea severity in adults with prediabetes and diabetes mellitus

Sleep and Breathing - Hypothyroidism is associated with a high frequency of obstructive sleep apnea (OSA). However, the prevalence of OSA in hypothyroid patients is not different from the general...     

Fibroblasts and extracellular matrix differently modulate MMP activation by primary and metastatic head and neck cancer cells

A genetically related pair of human head and neck cancer (HNSCC) cell lines derived from the same patient at different stages of disease was used to investigate the role of extracellular matrix, integrin, and CXCL12–CXCR4 receptor interactions and their signal pathways in MMP-2 and MMP-9 activation and cell invasion. We found that collagen I enhanced MMP-2 and MMP-9 secretion in both primary and metastatic HNSCC cells. Collagen I acted through α₂β₁ integrin to activate tyrosine kinases, protein kinase C, ERK1/2, and p38, which in turn activated MMP-2 and MMP-9 production. The signaling function was also involved in the enhancement of cell invasion. Experiments using cocultures between live and fixed cells demonstrated that direct contact between tumor and fibroblast cells was required to activate MMP-2 and MMP-9 secretion in both tumor cells and fibroblasts. The augmentation appears specific for MMP-2. Fibroblasts seem to be responsible for the increased MMP-2 in the coculture. In addition, fibroblast or tumor cell-conditioned media upregulated the secretion of MMP-2 and MMP-9 in HNSCC cells. These findings indicate that autocrine and paracrine factors are involved in the augmented secretion of MMPs in coculture. We also found that CXCL12-enhanced HNSCC cell invasion through paracrine-activated CXCR4, which triggered MMP-dependent cell invasion. Together, our results suggest that cell–matrix and cell–cell interactions including autocrine and paracrine factors play important roles in the invasive behavior of HNSCC via upregulation of MMP-2 and MMP-9.     

Frequent detection of Epstein-Barr Virus and cytomegalovirus but not JC virus DNA in cerebrospinal fluid samples from human immunodeficiency virus-infected patients in northern Thailand

Applying nested-PCRs, we frequently detected DNA of Epstein-Barr virus and cytomegalovirus but not JC virus in cerebrospinal fluid samples from 140 human immunodeficiency virus-infected patients with central nervous system symptoms in northern Thailand. Despite the low incidence of primary central nervous system lymphoma or cytomegalovirus encephalitis among Thai AIDS patients, Epstein-Barr virus and cytomegalovirus infections in the central nervous system are common.     

Reflections on a decade of research by ASEAN dental faculties: analysis of publications from ISI‐WOS databases from 2000 to 2009

This communication analyzed research publications in dentistry in the Institute of Scientific Information Web of Science databases of 10 dental faculties in the Association of South‐East Asian Nations (ASEAN) from 2000 to 2009. The term used for the “all‐document types” search was “Faculty of Dentistry/College of Dentistry.” Abstracts presented at regional meetings were also included in the analysis. The Times Higher Education System QS World University Rankings showed that universities in the region fare poorly in world university rankings. Only the National University of Singapore and Nanyang Technological University appeared in the top 100 in 2009; 19 universities in the region, including Indonesia, Malaysia, the Philippines, Singapore, and Thailand, appeared in the top 500. Data from the databases showed that research publications by dental institutes in the region fall short of their Asian counterparts. Singapore and Thailand are the most active in dental research of the ASEAN countries.