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BackgroundHeterotopic ossification (HO) is common after total joint arthroplasty and usually does not cause diagnostic problems. However, the occurrence of HO after oncologic prostheses implantation can be troublesome as it may mimic a locally recurrent tumor. Because this distinction could have a profound impact on the surgeon and patient, it is important to distinguish the two entities; to our knowledge, no study has evaluated this after oncologic endoprosthetic reconstruction around the knee after tumor resection.Questions/purposes(1) How common is the occurrence of HO compared with local recurrence (LR) after resection of bone sarcoma and the use of an oncologic knee prosthesis? (2) Are there any factors associated with the development of HO after limb salvage procedures with an endoprosthesis? (3) What features allow the surgeon to differentiate HO from a locally recurrent tumor in this setting?Methods‏Between 2002 and 2018, we performed 409 resections of primary bone tumors followed by reconstructions with oncologic endoprostheses. Of these, 17% (71 of 409) died before 2 years and did not have HO at that time, 2% (8 of 409) were lost to follow-up before 2 years, and another 2% (10 of 409) did not have radiographs available at a minimum of 2 years after surgery (and had not developed HO before then), and so could not be analyzed, leaving 320 patients for analysis in this retrospective study. Forty-two patients were excluded; 2% (5 of 320) for a history of failed allograft reconstruction, 3% (8 of 320) for pathologic fracture at presentation, 2% (6 of 320) for inadequate or complicated biopsy, 1% (2 of 320) for stem fractures, 2% (7 of 320) for stem loosening, and 4% (14 of 320) for extracortical bone bridging, leaving 278 patients for final evaluation. Two observers analyzed AP and lateral radiographs for signs of HO at a mean follow-up of 63 ± 33 months after surgery. We defined HO as extraskeletal bone formation in soft tissues. The primary study endpoint was survivorship free from HO, as ascertained by a competing-risks estimator. To identify factors associated with HO appearance, the demographic, radiographic, clinical, pathologic, and surgical characteristics were compared between patients with HO and those who had no lesion. Characteristic features were also compared between patients with HO and those with LR to help their differentiation. Univariate analysis was used for all statistical evaluations.ResultsHO developed in 8% (21 of 278) of patients in whom oncologic knee prosthesis was implanted. LR developed in 10% (28 of 278) of the patients. According to survivorship estimates, the HO-free survival rate was not different from the LR-free survival rate at 2 years after oncologic knee reconstruction (76 ± 5% [95% CI 63 to 87] versus 74 ± 5% [95% CI 62 to 88]; p = 0.19). History of infection was more common in patients with HO than in patients with no lesion (19% [4 of 21] versus 5% [12 of 229], Odds ratio [OR] 6 [95% CI 2 to 17]; p < 0.001). The male sex was more common in the HO group as well (76% [16 of 21] versus 55% [128 of 229], OR 2 [95% CI 1 to 5]; p = 0.03). The Modular Universal Tumor and Revision System prosthesis was more frequently used in patients with HO (67% [14 of 21]) compared to those with no lesions (40% [92 of 229]; OR 2 [95% CI 1 to 5]; p = 0.02).‏ The lesion border in radiographs was ill-defined in 19% (4 of 21) of patients with HO and 100% (28 of 28) of patients with LR (OR 8 [95% CI 3 to 20]; p < 0.001). The median time to the appearance of HO was shorter than the time to LR (8 months [3 to 13] versus 16 months [11 to 21], [95% CI 10 to 13]; p < 0.001). Pain at presentation was more frequent in patients with LR than in those with HO (86% [24 of 28] versus 14% [3 of 21], OR 36 [95% CI 7 to 181]; p < 0.001).ConclusionHO may occur after the use of oncologic knee prostheses for reconstruction after tumor resection. In most patients, HO could be differentiated from local recurrence through identifying a well-defined border on radiographs. Otherwise, factors such as an earlier time of presentation and absence of pain could suggest an HO, rather than an LR.Level of EvidenceLevel III, therapeutic study.  相似文献   
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Patients with chronic diseases are severely affected by acute coronavirus syndrome. In this regard, patients with beta thalassemia intermedia and diabetes mellitus (DM) are also at high risk for coronavirus‐induced respiratory failure. The present study aimed to report a case with COVID‐19 with a history of chronic diseases, beta thalassemia intermedia, and DM. A 25‐year‐old man visited with complaints of severe shortness of breath, fever, cough without sputum, and tachypnea and admitted to the Intensive Care Unit. The patient had a history of DM, beta thalassemia intermedia, and pervious history of the splenectomy. In peripheral complete blood count (CBC diff), the number of white blood cell count was 41,100 of which 38.6% were lymphocytes. We measured the normal platelet count, hemoglobin level (9.4), and red blood cell count (3.56). ESR was 97, CRP = pos+++ and PCR was positive. The high‐resolution lung CT indicated ground glass opacities in peripheral areas. The patient underwent 13 days of oxygen therapy with reservoir bag‐mask, non‐invasive ventilation, nasal oxygen, and pharmacological treatment with IFN‐β1a and meropenem, and finally discharged with an improvement of the clinical condition. Timely initiation of treatment is very important and significant for patients with beta thalassemia intermedia with COVID‐19, especially despite the underlying disease of DM. According to the present report, the use of IFN‐β1a was effective as a treatment option for COVID‐19.  相似文献   
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Lactobacillus crispatus is one of the most predominant species in the healthy vagina microbiota. Nevertheless, the interactions between this commensal bacterium and the immune system are largely unknown. Given the importance of the dendritic cells (DCs) in the regulation of the immunity, this study was performed to elucidate the influence of vaginal isolated L. crispatus SJ‐3C‐US from healthy Iranian women on DCs, either directly by exposure of DCs to ultraviolet‐inactivated (UVI) and heat‐killed (HK) L. crispatus SJ‐3C‐US or indirectly to its cell‐free supernatant (CFS), and the outcomes of immune response. In this work we showed that L. crispatus SJ‐3C‐US induced strong dose‐dependent activation of dendritic cells and production of high levels of IL‐10, whereas IL‐12p70 production was induced at low level in an inverse dose‐dependent manner. This stimulation skewed T cells polarization toward CD4+ CD25+ FOXP3+ Treg cells and production of IL‐10 in a dose‐dependent manner in mixed leukocyte reaction (MLR) test. The mode of bacterial inactivation did not affect the DCs activation pattern, upon encounter with L. crispatus SJ‐3C‐US. Moreover, while DCs stimulated with CFS showed moderate phenotypic maturation and IL‐10 production, it failed to skew T cells polarization toward CD4+ CD25+ FOXP3+ regulatory T cells (Treg) and production of IL‐10. This study showed that L. crispatus SJ‐3C‐US confers an anti‐inflammatory phenotype to DCs through up‐regulation of anti‐inflammatory/regulatory IL‐10 cytokine production and induction of CD4+ CD25+ FOXP3+ T cells at optimal dosage. Our findings suggest that L. crispatus SJ‐3C‐US could be a potent candidate as protective probiotic against human immune‐mediated pathologies, such as chronic inflammation, vaginitis or pelvic inflammatory disease (PID).  相似文献   
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Helicobacter pylori has grown to colonize inside the stomach of nearly half of the world’s population, turning into the most prevalent infections in the universe. Medical care failures noticeably confirm the need for a vaccine to hinder or deal with H. pylori. This review is planned to discuss the most known factors as a vaccine candidate, including single (AhpC, BG, CagA, KatA, Fla, Hsp, HWC, Lpp, LPS, NAP, OMP, OMV, SOD, Tpx, Urease, VacA) and multi-component vaccines. Many promising results in the field of single and multivalent vaccine can be seen, but there is no satisfactory outcome and neither a prophylactic nor a therapeutic vaccine to treat or eradicate the infection in human has been acquired. Hence, selecting suitable antigen is an important factor as an appropriate adjuvant. Taken all together, the development of efficient anti-H. pylori vaccines relies on the fully understanding of the interactions between H. pylori and its host immune system. Therefore, more work should be done on epitope mapping, analysis of molecular structure, and determination of the antigen determinant region as well due to design a vaccine, preferably a multi-component vaccine to elicit specific CD4 T-cell responses that are required for H. pylori vaccine efficacy.  相似文献   
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Pancreatic cancer is the fourth leading cause of cancer deaths in the USA. Although some patients will present with premalignant pancreatic lesions (i.e., intraductal papillary mucinous neoplasms) or localized tumors amenable to curative resection, the majority of patients will unfortunately present with technically unresectable or metastatic disease. This review of the recent medical literature will discuss the optimal work-up and management of premalignant pancreatic lesions and the surgical management of localized, borderline resectable, and locally advanced (i.e., unresectable) pancreatic tumors. It will focus on new criteria used to define surgical “resectability,” the significance and clinical impact of surgical margins, the role of multimodality therapy in the management of patients with borderline resectable or locally advanced tumors, the role of surgery for local or distant recurrence, and minimally invasive surgical approaches.  相似文献   
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ObjectivesTo measure central macular thickness in Jordanian patients with sickle cell disease who did not have retinopathy and compare the findings with age- and sex-matched controls using spectral domain optical coherence tomography (SDOCT).MethodsIn this cross-sectional study, participants underwent visual acuity testing, slit-lamp bio-microscopy, dilated ophthalmoscopy, and SDOCT imaging to measure central macular thickness. Macular quadrant measurements and thickness difference indexes (TDIs) were compared between groups.ResultsTwenty eyes with sickle cell disease and 20 control eyes were enrolled. The median visual acuity in both groups was 20/20. The mean macular thickness was significantly lower in eyes with sickle cell disease than in matched controls (mean difference, 22.15 ± 6.44 µm). Peripheral quadrants were all significantly thinner in eyes with sickle cell disease, especially in superior and temporal quadrants. TDIs were lower in eyes with sickle cell disease than in control eyes.ConclusionsEyes with sickle cell disease that had no clinical evidence of retinopathy exhibited significantly lower central macular thickness in all quadrants, compared with eyes in age- and sex-matched controls. SDOCT is a non-invasive imaging modality that can detect preclinical changes in eyes with sickle cell disease and can be used to screen and monitor the disease process.  相似文献   
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