• 한국입자에어로졸학회지
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• 제12권3호
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• pp.103-107
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• 2016

We conducted experiments on mask filters. We measured filtering efficiencies of several new mask filters which were manufactured by disassembling and reassembling of one type of mask filter. New filter (A+C: combination of the first layer and the third layer of the tested mask filter) showed the highest efficiency (97.7%) with the respiratory resistance of 98 pa.

• Tuberculosis and Respiratory Diseases
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• 제79권4호
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• pp.248-256
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• 2016

Somatic mutations that lead to hyperactivation of epidermal growth factor receptor (EGFR) signaling are detected in approximately 50% of lung adenocarcinoma in people from the Far East population and tyrosine kinase inhibitors are now the standard first line treatment for advanced disease. They have led to a doubling of progression-free survival and an increase in overall survival by more than 2 years. However, emergence of resistant clones has become the primary cause for treatment failure, and has created a new challenge in the daily management of patients with EGFR mutations. Identification of mechanisms leading to inhibitor resistance has led to new therapeutic modalities, some of which have now been adapted for patients with unsuccessful tyrosine kinase inhibitor treatment. In this review, we describe mechanisms of tyrosine kinase inhibitor resistance and the available strategies to overcoming resistance.

• Tuberculosis and Respiratory Diseases
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• 제75권5호
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• pp.188-198
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• 2013

Over the past decade, several kinase inhibitors have been approved based on their clinical benefit in cancer patients. Unfortunately, in many cases, patients develop resistance to these agents via secondary mutations and alternative mechanisms. To date, several major mechanisms of acquired resistance, such as secondary mutation of the epidermal growth factor receptor (EGFR) gene, amplification of the MET gene and overexpression of hepatocyte growth factor, have been reported. This review describes the recent findings on the mechanisms of primary and acquired resistance to EGFR tyrosine kinase inhibitors and acquired resistance to anaplastic lymphoma kinase inhibitors, primarily focusing on non-small cell lung carcinoma.

• 국제물리치료학회지
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• 제2권1호
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• pp.237-243
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• 2011

This study was to examine on the respiratory variables, heart rate and muscle activity between the static recovery and dynamic recovery after progressive resistance exercise to maximal point. Subjects were 15 students enrolled in N University. All were tested two times (static recovery and dynamic recovery) and were requested to perform a walking on a treadmill after progressive resistance exercise to maximal point. Electromyography(EMG) was used to monitor the muscle activity(TA: Tibialis Anterior, MG: Medial Gastrocnemius) during gait. CPEX-1 was used to measure the respiratory variables and heart rate. The dynamic recovery group was shown the significant lower heart rate than that of static recovery group at during gait. Respiratory rate showed statistically a significant difference. Electromyography(RMS, root mean square) showed a non-significant difference. But the dynamic recovery group of muscle activity was found highly in TA and MG. This study indicated that the dynamic recovery method evidenced more faster than the static recovery method. And this type of dynamic rest by walking can be a help of recovery after exercise.

• 수면정신생리
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• 제18권2호
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• pp.63-66
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• 2011

It has been controversial whether upper airway resistance syndrome (UARS) is a distinct syndrome or not since it was reported in 1993. The International Classification of Sleep Disorders classified UARS under obstructive sleep apnea syndrome (OSAS) in 2005. UARS can be diagnosed when the apnea-hypopnea index (AHI) is fewer than 5 events per hour, the simultaneously calculated respiratory disturbance index (RDI) is more than 5 events per hour due to abnormal non-apneic non-hypopneic respiratory events accompanying respiratory effort related arousals (RERAs), and oxygen saturation is greater than 92% at termination of an abnormal breathing event. Although esophageal pressure measurement remains the gold standard for detecting subtle breathing abnormality other than hypopnea and apnea, nasal pressure transducer has been most commonly used. RERAs include phase A2 of cyclical alternating patterns (CAPs) associated with EEG changes. Symptoms of OSAS can overlap with UARS, but chronic insomnia tends to be more common in UARS than in OSAS and clinical symptoms similar with functional somatic syndrome are also more common in UARS. In this journal, diagnostic and clinical differences between UARS and OSAS are reviewed.

• Clinical and Experimental Pediatrics
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• 제51권10호
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• pp.1031-1037
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• 2008

Macrolide antimicrobial agents including erythromycin, roxithromycin, clarithromycin, and azithromycin are commonly used in the treatment of respiratory tract infections in children. Newer macrolides that have structural modifications of older drug erythromycin show improved change in the spectrum of activity, dosing, and administration. However, recent studies reported that increasing use of macrolide antibiotics is the main force driving the development of macrolide resistance in streptococci. In particular, azithromycin use is more likely to select for macrolide resistance with Streptococcus pneumoniae than is clarithromycin use, a possible reflection of its much longer half life. Recently, erythromycin resistance rates of S. pneumoniae and Streptococcus pyogenes are rapidly increasing in Korea. Two main mechanisms of acquired macrolide resistance have been described, altered binding site on the bacterial ribosome encoded by the ermB gene and active macrolide efflux pump encoded by the mef gene. Relationship between the susceptibility of S. pneumoniae and the response to macrolides has been shown in studies of acute otitis media, but less clear in cases of pneumonia. This article reviews the spectrum of activity, pharmacokinetic properties, mechanisms of action and resistance, and clinical implication of resistance on the treatment of respiratory tract infections in children.

• 약학회지
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• 제48권6호
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• pp.364-368
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• 2004

The prevalence of resistance to a range of macrolides was determined for clinical isolates of common respiratory pathogens using NCCLS testing methods and interpretative criter ia.71.4% of Streptococcus pneumoniae, 62.3% of Staphylococcus aureus, 50.8% of coagulase-negative staphylococci and 4.4% of Strpetococcus pyogenes were erythromycin resistant. Also, the rates of resistance to other macrolides and clindamycin in these clinical isolates were as high as to eryth -romycin. Almost all of the macrolide-resistant isolates were positive for erm of the methylase gene, or mef of the efflux gene.

• 대한물리의학회지
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• 제17권2호
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• pp.95-100
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• 2022

PURPOSE: The purpose of this study was to compare the effect of depending on the location of applying chest expansion resistance exercise on the respiratory muscle strength stroke patients, and to suggest more effective interventions to improve respiratory function in stroke patients in clinical practice. METHODS: A total of 30 subjects were selected and divided into two groups, and chest cage extension resistance exercise was applied to the sternum and rib cage, respectively, and performed for 4 weeks, 3 times a week, for 20 minutes. In order to compare the general characteristics of the study subjects and the homogeneity of the group, the pre-experimental values were analyzed using the independent sample t-test. Paired-sample t-test was used for pre-post value comparison of maximum inspiratory pressure and maximum expiratory pressure in each group. Statistical significance was set to .05. RESULTS: Both the sternum application group and the rib cage application group showed a significant difference in the maximum inspiratory pressure according to the intervention. Also, there was a statistically significant difference in the maximum expiratory pressure in the sternum application group. CONCLUSION: As breathing exercise is important for stroke patients, based on the results of this study, if therapists perform sternal extension resistance exercise or rib extension resistance exercise according to the patient's condition and environment, it can help the breathing function of stroke patients.

• Asian Pacific Journal of Cancer Prevention
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• 제14권11호
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• pp.6757-6760
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• 2013

Gastric cancer is one of the most frequently occurring malignancies in the world. Development of multiple drug resistance (MDR) to chemotherapy is known as the major cause of treatment failure for gastric cancer. Multiple drug resistance 1/P-glycoprotein (MDR1/p-gp) contributes to drug resistance via ATP-dependent drug efflux pumps and is overexpressed in many solid tumors including gastric cancer. To investigate the role of MDR1 knockdown on drug resistance reversal, we knocked down MDR1 expression using shRNA in drug resistant gastric cancer cells and examined the consequences with regard to adriamycin (ADR) accumulation and drug-sensitivity. Two shRNAs efficiently inhibited mRNA and protein expression of MDR1 in SGC7901-MDR1 cells. MDR1 knockdown obviously decreased the ADR accumulation in cells and increased the sensitivity to ADR treatment. Together, our results revealed a crucial role of MDR1 in drug resistance and confirmed that MDR1 knockdown could reverse this phenotype in gastric cancer cells.

• Tuberculosis and Respiratory Diseases
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• 제77권4호
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• pp.172-177
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• 2014

Background: Pseudomonas aeruginosa infection is particularly associated with progressive and ultimately chronic recurrent respiratory infections in chronic obstructive pulmonary disease, bronchiectasis, chronic destroyed lung disease, and cystic fibrosis. Its treatment is also very complex because of drug resistance and recurrence. Methods: Forty eight cultures from 18 patients with recurrent P. aeruginosa pneumonia from 1998 to 2002 were included in this study. Two or more pairs of sputum cultures were performed during 2 or more different periods of recurrences. The comparison of strains was made according to the phenotypic patterns of antibiotic resistance and chromosomal fingerprinting by pulsed field gel electrophoresis (PFGE) using the genomic DNA of P. aeruginosa from the sputum culture. Results: Phenotypic patterns of antibiotic resistance of P. aeruginosa were not correlated with their prior antibiotic exposition. Fifteen of 18 patients (83.3%) had recurrent P. aeruginosa pneumonia caused by the strains with same PFGE pattern. Conclusion: These data suggest that the most of the recurrent P. aeruginosa infections in chronic lung disease occurred due to the relapse of prior infections. Further investigations should be performed for assessing the molecular mechanisms of the persistent colonization and for determining how to eradicate clonal persistence of P. aeruginosa.