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BackgroundA combination of immune-mediated vascular damage and routine use of systemic corticosteroid (CS) therapy in COVID-19 may significantly increase the risk and burden of osteonecrosis (ON) after COVID-19. This narrative review explores the pathogenesis, risk factors, and possible preventive and early treatment measures for ON in COVID-19.MethodsFor this narrative review, an extensive literature search was performed using the PubMed, Medline, and Science Direct databases from January 2000 to August 2021 for relevant articles on etiopathogenesis, epidemiology, clinical manifestations, and treatment of severe acute respiratory syndrome coronavirus (SARS-CoV) infection and steroid-induced ON (SION).ResultsPathogenesis of COVID-19, utility of corticosteroids in the treatment of COVID-19, pathogenesis of SION vis-a-vis SARS-CoV infection, associated risk factors, and early diagnosis and treatment of ON following CS therapy of SARS-CoV infection were discussed.ConclusionPreliminary data of COVID-19 and similar trends from the SARS 2003 epidemic indicate that the “angiocentric” pathogenesis of SARS-CoV-2 and treatment with high-dose CS may increase the risk of ON in COVID-19 patients. Risk stratification based on CS intake during COVID-19 treatment can help identify subjects at moderate to high-risk for ON where early preventive and follow-up plans can be initiated.  相似文献   
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Journal of Neuro-Oncology - This study was performed to determine the maximum tolerated dose (MTD) or recommended phase 2 dose (RP2D) of the immunomodulatory agent, lenalidomide, when administered...  相似文献   
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Background: Q-switched lasers are conventionally used for the treatment of black tattoo. However, they require multiple sittings, and the response may be slow due to competing epidermal pigment in dark skin. Objective: To compare the efficacy of Q-switched Nd:YAG laser alone with its combination with ultrapulse CO2 for the removal of black tattoo. Materials and methods: Sixty patients with black tattoo were randomized into two groups viz., group A and group B. Group A was treated with QS Nd:YAG laser (1064 nm) alone, and group B received combination of ablative ultrapulse CO2 followed by fixed-dose QS Nd:YAG laser (1064 nm), at 6-week interval for a maximum of 6 sittings. After each sitting, 3 independent physicians noted percentage of improvement that was evaluated using visual analogue scale (VAS) and grading system for tattoo ink lightening (TIL). Results: Combination laser (group B) showed statistically significant improvement in mean VAS score in the last 2 noted visits as compared to 1st session (p < 0.007, p < 0.001) and TIL mean score in last three noted visits as compared to 1st session (p < 0.008, p < 0.020, and p < 0.004). There was no statistically significant difference in the side effect profile of both the groups. Conclusion: For refractory professional tattoos, combination of ultrapulse CO2 laser and QS Nd:YAG laser is superior to QS Nd:YAG laser alone.  相似文献   
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PURPOSE: We evaluated the relationship between the ratio of free-to-total prostate specific antigen (PSA) and prostate pathology, including grade, stage and tumor volume, among patients with prostate cancer who underwent radical prostatectomy. MATERIALS AND METHODS: We prospectively analyzed 54 consecutive patients with prostate cancer who underwent radical prostatectomy and in whom frozen serum was available for assessment of free-to-total PSA ratio. Pathological review was done with whole mount sections, and total tumor volume was determined by planimetry. Comparison between free-to-total PSA ratio and pathological parameters was performed using the Pearson correlation coefficient. RESULTS: Among the 54 patients mean total and free-to-total PSA ratio were 5.81 and 14.2 ng./ml., respectively, and free-to-total PSA ratio directly correlated with prostate volume (p = 0.037), and inversely correlated with Gleason score (p = 0.012) and extracapsular disease (p = 0.0074). Furthermore, there was a significant relationship between free-to-total PSA ratio and pathological stage pT2a/b in 39 cases versus pT3a/b in 15 (p = 0.005). Overall, there was no correlation between free-to-total PSA ratio and tumor volume. However, among 37 patients with an increased PSA, defined as greater than 4.0 ng./ml., a significant inverse relationship between free-to-total PSA ratio and tumor volume was identified (p = 0.01). Among this subset there was only a weak correlation with prostate volume (p = 0.049). CONCLUSIONS: Our findings suggest that free-to-total PSA ratio may be predictive of tumor biology among those patients with a total PSA of greater than 4 ng./ml. as evidenced by good correlation with tumor grade and volume. This finding appears to be independent of prostate volume. These preliminary results suggest the need for additional studies among patients with an increased PSA designed to evaluate the potential role of free-to-total PSA ratio in combination with traditional clinical variables in the prediction of prostate cancer pathology.  相似文献   
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Introduction

Prostate carcinoma is still a dreaded disease wanting more effective treatment and definitive early detection for a better prognosis and cure of life.

Objective

The present study was planned to investigate the correlation of vascular endothelial growth factor (VEGF) expression level and microvessel density (MVD) between the BPH and prostate cancer subjects to analyze their diagnostic and prognostic value.

Subjects and methods

Freshly diagnosed histopathologically confirmed 50 cases of prostate cancer and 50 cases of BPH were included. Expression level of VEGF was measured using Immunohistochemistry (IHC), while MVD was determined via CD34 endothelium-specific antibodies. In the case group, we have also recorded the Gleason's score of prostate cancer and investigated its correlation with angiogenic factor VEGF and MVD CD34.

Results

The study showed a statistically significant difference value of VEGF expression level between the prostate cancer and BPH group (p < 0.001). The mean MVD CD34 in the prostate cancer and BPH groups were 29.66 ± 0.21 and 9.96 ± 0.25, respectively. The difference of MVD CD34 expression between the groups was also found significant (p < 0.001). VEGF scoring was significantly correlated with Gleason's scores of prostate cancer (p = 0.005).

Conclusions

The present findings may support the assumption that VEGF and CD34 expression level might have an important role in the prediction of prostate cancer as it was significantly differed with BPH. In addition, VEGF expression level showed intense staining in the tissue samples with higher grading of prostate cancer which reveals its importance as prognostic marker.  相似文献   
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