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1.
BackgroundIn shoulder arthroplasty, bone resorption around the stem can lead to stem loosening and makes surgery difficult at the time of revision. Proximal bone resorption after reverse shoulder arthroplasty can cause instability because of a decrease of deltoid wrapping effect. As factors of the stem itself, such as stem coating, shape, length, and use of bone cement, may also affect bone resorption, a single-stem model should be used to compare bone resorptions between different pathologies and surgical procedures. However, to date, a few reports have compared these differences in detail using a single-stem model. Therefore, we investigated the prevalence and location of humeral bone resorption in a single-stem model.MethodsThe study included 100 shoulders that underwent anatomical total shoulder arthroplasty (TSA) or humeral head replacement (HHR) with a single uncemented humeral stem from 2008 to 2018. The patients were 31 men and 69 women. The mean age at surgery was 72.9 years (range, 41-86 years). The patients were divided into three groups: especially, 25, 61, and 14 shoulders received TSA for primary osteoarthritis without rotator cuff tears (TSA group), HHR using an anatomical head with rotator cuff repair for cuff tear arthropathy (CTA) (HHR group), and HHR using a CTA head without rotator cuff repair (CTA group), respectively. Patients were monitored for a mean of 56 months (range, 12-98 months). The location of bone resorption was divided into seven zones as follows: zone 1, greater tuberosity; zone 2, lateral diaphysis; zone 3, lateral diaphysis beyond the deltoid tuberosity; zone 4, tip of the stem; zone 5, medial diaphysis beyond the deltoid tuberosity; zone 6, medial diaphysis; and zone 7, calcar region. The degree of bone resorption was classified from grade 0 to 4.ResultsBone resorption of grade 3 or higher was significantly more frequent at the greater tuberosity in the HHR and CTA groups (P < .001 and P < .001, respectively) than that in the TSA group. Grade 4 bone resorption was significantly more frequent in the CTA than that in the TSA and HHR groups in zone 1 (P = .016 and P = .041, respectively).ConclusionThe state of attachment of the rotator cuff to the greater tuberosity might affect bone resorption at the greater tuberosity, such as the greater tuberosity after shoulder arthroplasty. In cases of shoulder arthroplasty for arthropathy with rotator cuff tear, performing rotator cuff repair might prevent bone resorption.Level of evidenceLevel IV; Prognosis Study  相似文献   
2.
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   
3.
Cancer stem cells (CSCs) play a decisive role in the development and progression of cancer. To investigate CSCs in Epstein‐Barr virus (EBV)‐associated carcinoma (EBVaGC), we screened previously reported stem cell markers of gastric cancer in EBV‐infected gastric cancer cell lines (TMK1 and NUGC3) and identified CD44v6v9 double positive cells as candidate CSCs. CD44v6/v9+/+ cells were sorted from EBVaGC cell line (SNU719) cells and EBV‐infected TMK1 cells and these cell populations showed high spheroid‐forming ability and tumor formation in SCID mice compared with the respective CD44v6/v9?/? cells. Sphere‐forming ability was dependent on the nuclear factor‐κB (NF‐κB) signaling pathway, which was confirmed by decrease of sphere formation ability under BAY 11‐7082. Small interfering RNA knockdown of latent membrane protein 2A (LMP2A), one of the latent gene products of EBV infection, decreased spheroid formation in SNU719 cells. Transfection of the LMP2A gene increased the sphere‐forming ability of TMK1 cells, which was mediated through NF‐κB signaling. Together, these results indicate that CD44v6v9+/+ cells are CSCs in EBVaGC that are maintained through the LMP2A/NF‐κB pathway. Future studies should investigate CD44v6/v9+/+ cells in normal and neoplastic gastric epithelium to prevent and treat this specific subtype of gastric cancer infected with EBV.  相似文献   
4.
The aim of this study was to investigate the association between changes in the levels of vascular endothelial growth factors (VEGFs) after treatment with bevacizumab and gemcitabine (Bev-Gem) and the clinical outcome. Platinum-resistant ovarian cancer patients treated with Bev-Gem therapy at our hospital between 2014 and 2018 were identified. Serum VEGF levels at the first and second treatment cycle were measured by ELISA. All patients were categorized into two groups—patients with > 50% decrease in serum VEGF-A levels (Group A) and patients with < 50% decrease serum VEGF-A levels (Group B). The association between clinical outcome and serum VEGF levels was investigated between the two groups. Among 18 patients, 10 were in Group A and 8 in Group B. Group A exhibited a lower response rate (0% vs.75% p < 0.01) and clinical benefit rate (60% vs.100% p = 0.02) than Group B. The median serum VEGF-A level of Group A before the first cycle of Bev-Gem therapy was higher than that in Group B (61.2 vs. 3.7 pg/mL, p < 0.01). Group A exhibited worse PFS (7 vs., 10 months, p < 0.01) and OS (17 vs. 26 months, p = 0.04) than Group B. There were more patients with > 10% increase in serum VEGF-B levels in Group A than in Group B (p < 0.01). The rapid decrease in VEGF-A levels and the resultant increase in serum VEGF-B levels might be associated with an unfavorable clinical outcome. Large-scale studies are needed to further examine these results.  相似文献   
5.

Background

Photosensitizers used for photodynamic therapy (PDT) to treat dermatologic disease are metabolized into mainly protoporphyrin IX (PpIX), which has five absorption wavelength peaks: 410?nm, 510?nm, 545?nm, 580?nm, and 630?nm. Although only red light around 635?nm and blue light around 400?nm are used as light sources for PDT, the efficiency of PDT might be improved by using multiple wavelengths, including those that correspond to the other absorption peaks of PpIX. Furthermore, because the target disease often occurs on the face, a flexible-type light-source unit that can be fitted to the lesion without unnecessarily exposing the mucous membranes, e.g., the eyes, nostrils, and mouth, is preferred.

Objective

We investigated the efficacy of a flexible light-emitting diode (LED) unit that emits multiple wavelengths to improve PDT effects.

Methods

HaCaT cells were incubated with 5-ALA and subsequently irradiated with either a single wavelength or sequentially with two wavelengths. Cell viability and reactive oxygen species were analyzed. Nude mice were implanted with COLO679 cells by subcutaneous injection into the flank. 5-ALA was subcutaneously injected into the tumor. The tumor was irradiated with 50?J/cm2 (day 0) and assessed daily until day 21.

Results

The synergistic PDT effects of dual-wavelength irradiation and reactive oxygen species production were highest with the 405-nm and 505-nm wavelength combination. This dual wavelength combination was also the most effective in vivo.

Conclusion

We could therefore conclude that dual-wavelength PDT is an efficient strategy for improving the therapeutic effects of PDT. Using a flexible LED unit is expected to achieve more uniform irradiation of uneven areas.  相似文献   
6.

BACKGROUND CONTEXT

It is widely recognized that sagittal spinal alignment changes with age. However, there are presently no clear benchmarks for such values or those for the cervical spine in the general population. Quality epidemiological studies are needed to establish standards for spinal alignment deviation.

OBJECTIVES

In this study of an aged Japanese population, we employed random sampling from the basic resident registry of a rural town for subject selection to determine reference values of sagittal spinal alignment including the cervical spine.

STUDY DESIGN

Japanese resident cohort study based on a municipal registry.

PATIENT SAMPLE

A total of 413 aged people randomly sampled from the resident registry of a rural Japanese town.

OUTCOME MEASURES

All subjects underwent a whole spine lateral radiograph for measurement of sagittal spinal alignment parameters.

METHODS

Registered citizens of 50 to 89 years old were targeted for this survey. We established eight groups based on age (50s, 60s, 70s, and 80s) and gender (male and female) after random sampling from the resident registry of Obuse town in 2014. A total of 413 people (203 males and 210 females) were enrolled. Radiographic parameters of sagittal spinal alignment of the cohort were measured and analyzed. Funding for this study was provided by the Japan Orthopaedics and Traumatology Research Foundation (10,000 USD), the Japanese Orthopaedic Association (5,000 USD), the Japanese Society for Musculoskeletal Medicine (40,000 USD), and the Nakatomi Foundation (15,000 USD).

RESULTS

Global spinal alignments became more misaligned with age for both genders. Sagittal vertical axis (SVA) forward shift was significantly more frequent in 80s males and 70s females, and SVA in 80s females was a mean of 66 mm forward of that of 50s females. Cervical protrusion was markedly greater in 60s males onwards. In women, lumbar lordosis and posterior pelvic inclination were noticeable from a younger age than in men. The amount of pelvic tilt misalignment in female subjects was approximately 10 years earlier than their male counterparts.

CONCLUSIONS

This first resident cohort of Japanese individuals determined average spinal alignment parameters by age and gender. Spinal balance generally shifts forward as age increases. A forward shift in the upper cervical spine occurs first in men, whereas lumbopelvic alignment shift occurs first in women.  相似文献   
7.

Background

On April 1, 2016, the Ministerial ordinance was enforced, and musculoskeletal examination of the extremities was made mandatory. From 2008, the University of us started musculoskeletal direct examination. To expand the examination, from 2016, we started to use the marksheet-type questionnaire. This study aimed to report the results of a musculoskeletal examination and investigate the association between musculoskeletal examination and age/gender and reports the reliability of the collected questionnaire data.

Methods

Direct musculoskeletal examination was performed in K school by 7 orthopedic surgeons. A marksheet-type screening questionnaire was distributed to all the elementary and junior high school students in Tsukuba and Hitachiomiya cities. The rates of abnormal findings for scoliosis, standing flexion, full squatting with the heels on the floor, general joint laxity, and standing on one leg, torticollis, and flat feet were calculated. We compared the results of the questionnaire and direct examination and calculated sensitivity, specificity, and odds ratio.

Results

A total of 1844 students in K school had direct examination, and 22,494 questionnaires were able to correct in Tsukuba and Hitachiomiya cities. The rates of abnormal findings in direct examination/questionnaire in scoliosis, standing flexion, full squat, general joint laxity, standing on one leg, torticollis and flat foot were 18.7% (344/1842)/5.1% (1094/21441), 20.2% (372/1841)/26.6% (5817/22078), 6.2% (114/1832)/6.9% (1516/22101), 7.5% (1648/22252), 4.9% (1100/22077), 2.2% (31/1844)/1.2% (272/21687), and 12.5% (231/1842)/8.7% (1785/20871), respectively. Sensitivities of the questionnaire for scoliosis, stand flexion, full squatting, torticollis, and flat feet were 16.8% (53/316), 67.9% (250/368), 48.2% (55/114), 18.9% (7/37), and 32.2% (65/202), respectively.

Conclusion

We reported the result of musculoskeletal examination. Accuracy and reliability of this questionnaire were not satisfactory. To perform high quality musculoskeletal examinations, we will aim to increase the quality of screening methods.  相似文献   
8.
9.
The effect of alcohol intake on varicose veins (VV) has not been determined by its consumption level. The aim of this study was to investigate the association between alcohol intake and VV in an elderly general population. Using a cross‐sectional approach, the Shimane CoHRE Study data, comprising a total of 1060 participants, were analyzed. By multivariate regression analysis adjusted with basic characteristics, past work history, lifestyle‐related factors and medical history, compared with non‐drinkers, mild drinkers (<20.0 g/day) showed a significantly lower adjusted odds ratio (aOR) of VV (aOR = 0.64, P = 0.036). In a similar way, regular drinkers (1–5 days/week) showed a significantly lower aOR of VV when compared with occasional drinkers (aOR = 0.57, P = 0.032). VV and alcohol intake showed J‐curve relationships. In a stratified analysis by alcohol consumption levels, the association of smoking and VV were also observed in moderate to heavy drinkers and habitual drinkers. These findings can provide better understanding of pathophysiological mechanism and be used for evidence‐based patient education.  相似文献   
10.
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