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1.
OBJECTIVES: Dental lasers have been used for uncovering submerged implants as well as decontaminating implant surfaces when treating peri-implantitis. The objective of this study was to compare the possible alterations of the smooth surface and resorbable blast material (RBM) surface implants after using NdYAG and CO(2) lasers at various energies. MATERIALS AND METHODS: Ten smooth surface implants and 10 RBM surface implants were used. Two smooth surface implants and 2 RBM surface implants served as a control group that was not lased. The remaining implants were treated using NdYAG and CO(2) lasers. The surface of each implant was treated for 10 seconds on the second and third threads. The smooth surface implants (group 1) were treated using a pulsed contact NdYAG laser at power settings of 1, 2, 3.5, and 5 W, which are commonly used for soft tissue surgery; the corresponding energy and frequency were 50 mJ and 20 Hz, 100 mJ and 20 Hz, 350 mJ and 10 Hz, and 250 mJ and 20 Hz, respectively. The group 2 RBM implants were treated using a pulsed contact NdYAG laser. The group 3 smooth surface implants were treated using a pulsed wave non-contact CO(2) laser at 1, 2, 3.5, and 5 W, and the group 4 RBM implants were treated using a pulsed wave non-contact CO(2) laser. Data were analyzed using scanning electron microscopy. RESULTS: The control surface was very regular and smooth. After NdYAG laser treatment, the implant surface showed alterations of all the surfaces. The amount of damage was proportional to the power. A remarkable finding was the similarity of the lased areas on the smooth and RBM surfaces. CO(2) laser at power settings of 1.0 or 2.0 W did not alter the implant surface, regardless of implant type. At settings of 3.5 and 5 W, there was destruction of the micromachined groove and gas formation. CONCLUSION: This study supports that CO(2) laser treatment appears more useful than NdYAG laser treatment and CO(2) laser does not damage titanium implant surface, which should be of value when uncovering submerged implants and treating peri-implantitis.  相似文献   
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Belgian Landrace piglets were experimentally infected with eggs of aTaenia sp. of Korean origin. At autopsy, metacestodes were present only in the livers. The proportion of degenerated metacestodes increased from 12%–39% at 5 weeks to 94%–100% at 10 weeks after infection. A sandwich enzyme-linked immunosorbent assay (ELISA) using monoclonal antibodies raised against the excretory-secretory products ofT. saginata metacestodes detected circulating antigen in the sera of the pigs at 1 week post-infection. A good correlation was found between the presence of viable metacestodes and the detection of circulating antigen; the latter disappeared as the metacestodes died off. However, the antibodies were detected only after 3 weeks of infection and onwards until the necropsy of the pigs.Financial support for this study was provided by the Institute for Scientific Research in Industries and Agriculture (IWONL, Brussels)  相似文献   
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An investigation was carried out into how stimulation frequency and stimulation history affect the potentiation of muscle force during 20s of constant stimulation of the two knee extensors in isometric conditions. Stimulation frequency significantly affected the potentiation pattern: low-frequency (2.5–10 Hz) stimulation showed a reduction and subsequent enhancement of force, and high-frequency (14.3–25 Hz) stimulation showed only enhancement of force. The degree of enhancement in force and time-to-peak decreased with the stimulation frequency. Whereas conditioning stimulation (both 40 Hz and 14.3 Hz) significantly enhanced the muscle force above 85%, following main stimulation (14.3 Hz) after short rest (10 s and 50 s, respectively) induced little force enhancement (below 8%). In particular, when the frequency of the conditioning stimulation was 14.3 Hz, the initial force at the main stimulation showed a very similar value to the final force value of the conditioning stimulation (above 90% similarity). The potentiated twitch force slowly decayed during rest, with an average time constant of 2.4 min. These observations indicate that muscle potentiation depends on the stimulation frequency and stimulation history, and therefore a computer model of potentiation can play an important role in predicting muscle force and body movement induced by electrical stimulation.  相似文献   
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Evidence suggests that diets with high pro-inflammatory potential may play a substantial role in the origin of gastric inflammation. This study aimed to examine the association between the energy-adjusted dietary inflammatory index (E-DIITM) and gastric diseases at baseline and after a mean follow-up of 7.4 years in a Korean population. A total of 144,196 participants from the Korean Genome and Epidemiology Study_Health Examination (KoGES_HEXA) cohort were included. E-DII scores were computed using a validated semi-quantitative food frequency questionnaire. Multivariate logistic regression and Cox proportional hazards regression were used to assess the association between the E-DII and gastric disease risk. In the prospective analysis, the risk of developing gastric disease was significantly increased among individuals in the highest quartile of E-DII compared to those in the lowest quartile (HRquartile4vs1 = 1.22; 95% CI = 1.08–1.38). Prospective analysis also showed an increased risk in the incidence of gastritis (HRquartile4vs1 = 1.19; 95% CI = 1.04–1.37), gastric ulcers (HRquartile4vs1 = 1.47; 95% CI = 1.16–1.85), and gastric and duodenal ulcers (HRquartile4vs1 = 1.46; 95% CI = 1.17–1.81) in the highest E-DII quartile compared to the lowest quartile. In the cross-sectional analysis, the E-DII score was not associated with the risk of gastric disease. Our results suggest that a pro-inflammatory diet, indicated by high E-DII scores, is prospectively associated with an increased risk of gastric diseases. These results highlight the significance of an anti-inflammatory diet in lowering the risk of gastric disease risk in the general population.  相似文献   
7.
BackgroundNumerous patients around the globe are dying from coronavirus disease 2019 (COVID-19). While age is a known risk factor, risk analysis in the young generation is lacking. The present study aimed to evaluate the clinical features and mortality risk factors in younger patients (≤ 50 years) with a critical case of COVID-19 in comparison with those among older patients (> 50 years) in Korea.MethodsWe analyzed the data of adult patients only in critical condition (requiring high flow nasal cannula oxygen therapy or higher respiratory support) hospitalized with PCR-confirmed COVID-19 at 11 hospitals in Korea from July 1, 2021 to November 30, 2021 when the delta variant was a dominant strain. Patients’ electronic medical records were reviewed to identify clinical characteristics.ResultsDuring the study period, 448 patients were enrolled. One hundred and forty-two were aged 50 years or younger (the younger group), while 306 were above 50 years of age (the older group). The most common pre-existing conditions in the younger group were diabetes mellitus and hypertension, and 69.7% of the patients had a body mass index (BMI) > 25 kg/m2. Of 142 younger patients, 31 of 142 patients (21.8%, 19 women) did not have these pre-existing conditions. The overall case fatality rate among severity cases was 21.0%, and it differed according to age: 5.6% (n = 8/142) in the younger group, 28.1% in the older group, and 38% in the ≥ 65 years group. Age (odds ratio [OR], 7.902; 95% confidence interval [CI], 2.754–18.181), mechanical ventilation therapy (OR, 17.233; 95% CI, 8.439–35.192), highest creatinine > 1.5 mg/dL (OR, 17.631; 95% CI, 8.321–37.357), and combined blood stream infection (OR, 7.092; 95% CI, 1.061–18.181) were identified as independent predictors of mortality in total patients. Similar patterns were observed in age-specific analyses, but most results were statistically insignificant in multivariate analysis due to the low number of deaths in the younger group. The full vaccination rate was very low among study population (13.6%), and only three patients were fully vaccinated, with none of the patients who died having been fully vaccinated in the younger group. Seven of eight patients who died had a pre-existing condition or were obese (BMI > 25 kg/m2), and the one remaining patient died from a secondary infection.ConclusionAbout 22% of the patients in the young critical group did not have an underlying disease or obesity, but the rate of obesity (BMI > 25 kg/m2) was high, with a fatality rate of 5.6%. The full vaccination rate was extremely low compared to the general population of the same age group, showing that non-vaccination has a grave impact on the progression of COVID-19 to a critical condition. The findings of this study highlight the need for measures to prevent critical progression of COVID-19, such as vaccinations and targeting young adults especially having risk factors.  相似文献   
8.
There have been many methods to use the superficial inferior epigastric vein (SIEV) for improvement of flap circulation during breast reconstruction with free abdominal flap. If the SIEV is used for the purpose of adding another draining route, selection of ideal recipient vein is a crucial step. We reviewed our experiences of using the SIEV as additional vein in free transverse rectus abdominis musculocutaneous or deep inferior epigastric artery perforator breast reconstruction to find out the ideal recipient vein for SIEV. Between April 2006 and July 2010, 153 cases of breast reconstruction were performed using free transverse rectus abdominis musculocutaneous or deep inferior epigastric artery perforator flaps. Additional SIEV anastomosis was performed in 45 cases with risk factors. First choice of the recipient vein was the lateral thoracic vein if the SIEV was placed laterally after the inset of the flap. If the lateral thoracic vein was ablated with lymph node dissection, the branch of the thoracoacromial vein was selected. If the SIEV was placed medially, the perforator of the internal mammary vein was used. No vascular compromise was observed in cases with additional SIEV anastomosis with those recipient veins, whereas 9 cases of flap-related complications were observed in the remaining 108 cases without additional SIEV anastomosis. The incidences of the venous congestion were significantly different between the 2 groups. Combination of the lateral thoracic vein, branch of the thoracoacromial vein, and the perforator of the internal mammary vein provided an excellent choice of the recipient vein for the SIEV with reliability and availability.  相似文献   
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Marine organisms exhibit a rich chemical content that possess unique structural features as compared to terrestrial metabolites. Among marine resources, marine algae are a rich source of chemically diverse compounds with the possibility of their potential use as a novel class of artificial food ingredients and antimicrobial agents. The objective of this brief review is to identify new candidate drugs for antimicrobial activity against food-borne pathogenic bacteria. Bioactive compounds derived from brown algae are discussed, namely phlorotannins, that have anti-microbial effects and therefore may be useful to explore as potential antimicrobial agents for the food and pharmaceutical industries.  相似文献   
10.
This study describes a retrospective analysis on the transplant outcome of 56 consecutive patients with myelodysplastic syndrome (MDS) according to their response to hypomethylating agents (HMA). While 2‐yr disease‐free survival (DFS) of patients who transformed to acute myeloid leukemia (= 12) was 25%, that of the remaining patients with MDS according to response to HMA was 73.1%, 68.1%, 50.0%, and 20.8% in G‐COR (group of continuous response, = 19), G‐NoC (group of no change, = 15), G‐LOR (group of loss of response, = 6), and G‐DP (group of disease progression, = 4), respectively. When dichotomized as G‐COR/G‐NoC versus G‐LOR/G‐DP, significantly different 2‐yr DFS (71.0% vs. 33.3%; = 0.004) and relapse (14.1% vs. 46.7%; = 0.016) were demonstrated. On multivariate analysis, G‐LOR/G‐DP [hazard ratio (HR), 3.91; = 0.008] and poor karyotype at transplantation (HR, 2.69; = 0.017) were the significant predictors for poor DFS, as G‐LOR/G‐DP was for relapse (HR, 6.28; = 0.011). DFS was significantly poor in patients with any of the two predictors in all MDS (81.5% vs. 34.9%; = 0.001) or higher‐risk MDS (HrMDS) at the time of HMA (80.7% vs. 29.2%; = 0.005). G‐COR showed a trend of better DFS compared with G‐NoC among HrMDS (74.6% vs. 36.5%; = 0.090). These results implicate the significance of response to HMA on hematopoietic stem cell transplantation (HSCT) outcomes and support the need for future study to verify the suggested strategy of proceeding to transplantation before LOR or DP, especially for HrMDS.  相似文献   
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