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1.
Background

Osimertinib is effective in patients with T790M mutation-positive advanced non-small-cell lung cancer (NSCLC) resistant to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). However, its effectiveness and safety in patients with poor performance status (PS) are unknown.

Methods

Enrolled patients showed disease progression after treatment with gefitinib, erlotinib, or afatinib; T790M mutation; stage IIIB, IV, or recurrent disease; and PS of 2–4. Osimertinib was orally administered at a dose of 80 mg/day. The primary endpoint of this phase II study (registration, jRCTs061180018) was response rate and the secondary endpoints were progression-free survival (PFS), overall survival (OS), disease control rate, and safety.

Results

Thirty-three patients were enrolled, of which 69.7% and 24.2% had PS of 2 and 3, respectively. One patient was excluded due to protocol violation; in the remaining 32 patients, the response rate was 53.1%; disease control rate was 75.0%; PFS was 5.1 months; and OS was 10.0 months. The most frequent adverse event of grade 3 or higher severity was lymphopenia (12.1%). Interstitial lung disease (ILD) was observed at all grades and at grades 3–5 in 15.2% (5/33) and 6.1% (2/33) of patients, respectively. Treatment-related death due to ILD occurred in one patient. Patients negative for activating EGFR mutations after osimertinib administration had longer median PFS than those positive for these mutations.

Conclusion

Osimertinib was sufficiently effective in EGFR-TKI-resistant, poor PS patients with T790M mutation-positive advanced NSCLC. Plasma EGFR mutation clearance after TKI treatment could predict the response to EGFR-TKIs.

  相似文献   
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BackgroundThe onset of carious lesions and periodontal disease originates in plaque formed from dental bacteria. Appropriate plaque control is therefore important. Dental floss is one instrument used to control plaque. The influence of guardians is an important factor in whether children use dental floss regularly. However, the use of dental floss among school-age children and the relationship between use and family background has yet to be examined.AimIn this study, we conducted a questionnaire survey to examine rates of dental floss use and other related factors among elementary school children and their guardians.MethodsSurveys were sent to 298 guardians of children in grades 1–6 at an elementary school in Japan and 283 valid responses were received. Statistical analyses were carried out, with child’s use of dental floss as a dependent variable and grade, sex, guardian assistance with child's tooth brushing, frequency of child’s dental check-ups, and guardian's use of dental floss as independent variables.ResultsThe results revealed that 18.4% of children used dental floss compared with 52.7% of guardians, suggesting that the rate of usage among children is much lower than that among guardians. Logistic regression analysis further revealed that guardian's use of dental floss was significantly related to dental floss use among children.ConclusionThe guardian's use of dental floss was associated with dental floss use among their children in this group of Japanese elementary school.  相似文献   
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Effects of ATP on the intracellular free calcium ion concentration ([Ca2+]i) in the rabbit eye suprachoroid were investigated by means of fura-2 microfluorophotometry. ATP application (10 to 100 microM) elicited a dose-dependent biphasic [Ca2+]i-increase: a fast phase typically peaking within 30 s and a following slow plateau phase, which lasted during the presence of ATP. The slow plateau phase was markedly diminished by removal of extracellular Ca2+, whereas the fast phase remained. An inhibitor of Ca2+ release from the sarcoplasmic reticulum (TMB-8), an endoplasmic Ca2+-ATPase inhibitor (thapsigargin) and a phospholipase C (PLC) inhibitor (U-73122) diminished the fast phase. A P2 receptor antagonist (Suramin) inhibited the ATP-induced [Ca2+]i-response. The potency order of ATP and related substances in producing the [Ca2+]i-elevation was UTP approximately equals ATP>ATP-gamma-S>ITP>ADP. beta,gamma-MethyleneATP, 2-methylthioATP and UDP evoked no response. This order is consistent with the P2Y2 receptor characteristics. Cross-desensitization between ATP and UTP excludes the co-existence of the other types of receptors. In conclusion, the ATP-induced [Ca2+]i-elevation in the rabbit eye suprachoroid was elicited by the Ca2+ release from the PLC-dependent, thapsigargin-sensitive intracellular Ca2+ storage sites by activating P2Y2 nucleotide receptors.  相似文献   
9.

Background

Oral appliance (OA) therapy for obstructive sleep apnea (OSA) has only been part of Japan’s National Health care coverage plan since 2004. Subsequently, not enough time has passed to establish the medical trends and characteristics of OSA patients in Japanese Dental Hospitals.

Aim

The aim of this study was to investigate the medical trends and the characteristics in patients with OSA who visited our clinic, and to compare our findings with previous studies.

Setting and design

Epidemiological survey (retrospective study).

Materials and methods

Two hundred and one patients were recruited at the Internal Medicine Division in the Tsurumi University Dental Hospital from February 2006 to December 2008, consecutively. Patients received a medical interview, and a detailed sleep analysis that included a polysomnography (PSG) to verify the exact nature of their condition. The efficacy of OA was assessed in 49 patients who wore an OA and underwent PSG.

Results

Of all subjects, 141 patients visited the Prosthodontic Division to receive OA therapy, 38 patients were treated or received a follow up examination in the Internal Medicine Division. The dropout rate was 10.4% in the all subjects, 17.0% in patients who visited the Prosthodontic Division. The male-to-female ratio was 3.3:1, 3.0:1 in patients who visited the Prosthodontic Division. In addition, females had a lower rate of OAS severity than males. In our patients, the major complication was hypertension and cardiac disease. The success rate of OA was 75.5%.

Conclusion

This approach allowed us to reveal some of the trends and characteristics in our patients.  相似文献   
10.
A full-balanced occlusion is essential for mouthguards. It has been reported that a balanced occlusion for upper and lower anterior teeth is essential for prevention of injuries occurring to the maxillary anterior teeth and alveolar bone caused by horizontal direct impact. The support of the mandibular teeth through the mouthguard is critical to prevent maxillary front tooth injury from a direct impact force. However, some vacuum mouthguard designs may not achieve a full-balanced occlusion. For example, when a player has a malocclusion, an elongated molar or premolar tooth, an open bite, a large over jet or a maxillary protrusion. An improved vacuum fabrication method is necessary to obtain full balanced occlusion in these cases as opposed to conventional vacuum type single-layer mouthguard technique.  相似文献   
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