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21.
In this work, we provide an up-to-date summary of the available molecular- and cell-related mechanisms by which alpha1-antitrypsin (AAT) protein could be of benefit in treating COVID-19 patients. As well, we demonstrate the current status in terms of the ongoing clinical trials using AAT in COVID-19 patients. Finally, we touch on the potential role gene therapy and stem cell-based gene therapy could have in such emerging and serious condition caused by the SARS-CoV-2 virus.  相似文献   
22.
Vitamin D is critical for calcium, phosphate homeostasis and for mineralization of the skeleton, especially during periods of rapid growth. Vitamin D Deficiency leads to rickets (in children) and osteomalacia (in adults). Expression and activation of the vitamin D receptor (VDR) are necessary for the effects of vitamin D, in which several single nucleotide polymorphisms have been identified especially (FokI, BsmI). In this study serum 25 (OH) vitamin D3 levels were estimated by Enzyme Linked Immunosorbent Assay [ELISA], VDR (FokI, BsmI) gene polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism assay [PCR–RFLP].Serum levels of calcium, phosphorus, alkaline phosphatase and ferritin were determined in 50 Pediatrics beta thalassemia major patients and 60 controls. Patients had significantly lower serum calcium (p < 0.001) lower serum vitamin D3 (p < 0.001) with elevated levels of phosphorus (p < 0.001) and alkaline phosphatase than controls (p = 0.04). Of the patients studied, 60 % had vitamin D deficiency (<20 ng/ml), 20 % had vitamin D insufficiency (21–30 ng/ml) and 20 % had sufficient vitamin D status (>30 ng/ml). Patients harboring mutant (Ff,ff) and wild (BB) genotypes were associated with lower serum calcium (p = 0.08, 0.02) respectively, lower vitamin D3 levels (p < 0.001, 0.01) respectively. They were also suffering from more bony complications although the difference was not statistically significant (p > 0.05). In conclusion, these results suggest that the VDR (FokI, BsmI) gene polymorphisms influence vitamin D status, (Ff,ff), BB genotypes had lower vitamin D levels, so they might influence risk of development of bone diseases in beta thalassemia major.  相似文献   
23.
We conducted a study to determine prevalence of HPV types in oropharyngeal cancers in the United States and establish a prevaccine baseline for monitoring the impact of vaccination. HPV DNA was extracted from tumor tissue samples from patients in whom cancer was diagnosed during 1995–2005. The samples were obtained from cancer registries and Residual Tissue Repository Program sites in the United States. HPV was detected and typed by using PCR reverse line blot assays. Among 557 invasive oropharyngeal squamous cell carcinomas, 72% were positive for HPV and 62% for vaccine types HPV16 or 18. Prevalence of HPV-16/18 was lower in women (53%) than in men (66%), and lower in non-Hispanic Black patients (31%) than in other racial/ethnic groups (68%–80%). Results indicate that vaccines could prevent most oropharyngeal cancers in the United States, but their effect may vary by demographic variables.  相似文献   
24.
The large surface area of highly porous titanium structures produced by additive manufacturing can be modified using biofunctionalizing surface treatments to improve the bone regeneration performance of these otherwise bioinert biomaterials. In this longitudinal study, we applied and compared three types of biofunctionalizing surface treatments, namely acid–alkali (AcAl), alkali–acid–heat treatment (AlAcH), and anodizing-heat treatment (AnH). The effects of treatments on apatite forming ability, cell attachment, cell proliferation, osteogenic gene expression, bone regeneration, biomechanical stability, and bone-biomaterial contact were evaluated using apatite forming ability test, cell culture assays, and animal experiments. It was found that AcAl and AnH work through completely different routes. While AcAl improved the apatite forming ability of as-manufactured (AsM) specimens, it did not have any positive effect on cell attachment, cell proliferation, and osteogenic gene expression. In contrast, AnH did not improve the apatite forming ability of AsM specimens but showed significantly better cell attachment, cell proliferation, and expression of osteogenic markers. The performance of AlAcH in terms of apatite forming ability and cell response was in between both extremes of AnH and AsM. AcAl resulted in significantly larger volumes of newly formed bone within the pores of the scaffold as compared to AnH. Interestingly, larger volumes of regenerated bone did not translate into improved biomechanical stability as AnH exhibited significantly better biomechanical stability as compared to AcAl suggesting that the beneficial effects of cell-nanotopography modulations somehow surpassed the benefits of improved apatite forming ability. In conclusion, the applied surface treatments have considerable effects on apatite forming ability, cell attachment, cell proliferation, and bone ingrowth of the studied biomaterials. The relationship between these properties and the bone-implant biomechanics is, however, not trivial.  相似文献   
25.
BackgroundTo provide information about pathogens’ coinfection prevalence with SARS‐CoV‐2 could be a real help to save patients’ lives. This study aims to evaluate the pathogens’ coinfection prevalence among COVID‐19 patients.MethodIn order to find all of the relevant articles, we used systematic search approach. Research‐based databases including PubMed, Web of Science, Embase, and Scopus, without language restrictions, were searched to identify the relevant bacterial, fungal, and viral coinfections among COVID‐19 cases from December 1, 2019, to August 23, 2021. In order to dig deeper, other scientific repositories such as Medrxiv were probed.ResultsA total of 13,023 studies were found through systematic search. After thorough analysis, only 64 studies with 61,547 patients were included in the study. The most common causative agents of coinfection among COVID‐19 patients were bacteria (pooled prevalence: 20.97%; 95% CI: 15.95–26.46; I 2: 99.9%) and less frequent were virus coinfections (pooled prevalence: 12.58%; 95% CI: 7.31–18.96; I 2: 98.7%). The pooled prevalence of fungal coinfections was also 12.60% (95% CI: 7.84–17.36; I 2: 98.3%). Meta‐regression analysis showed that the age sample size and WHO geographic region did not influenced heterogeneity.ConclusionWe identified a high prevalence of pathogenic microorganism coinfection among COVID‐19 patients. Because of this rate of coinfection empirical use of antibacterial, antifungal, and antiviral treatment are advisable specifically at the early stage of COVID‐19 infection. We also suggest running simultaneously diagnostic tests to identify other microbiological agents’ coinfection with SARS‐CoV‐2.  相似文献   
26.
Objective: The purpose of the study was to correlate between effect of pre-neoadjuvant chemotherapy (NACT) and post-NACT clinical, sonographic and pathologic features of the tumor and axillary lymph nodes (ALNs) and to raise the possibility of applying the concept of sentinel lymph node biopsy (SLNB) in patients with initially positive ALNs before NACT. Methods: A prospective study of 50 female patients with locally advanced breast cancer (LABC) with clinically palpable.and cytologically (under ultrasonographic guidance) positive ALNs. All patients received NACT and then referred for ultrasono- graphic assessment of the axilla regarding any detectable sonographic criteria of metastatic deposits in ALNs as well as the tumor size in relation to its prechemotherapy size, All patients were then subjected either to modified radical mastectomy or breast conserving surgery. The clinical, sonographic and pathological response of the tumor and the ALNs were documented, classified and correlated with each other. Results: Patients' mean age was 47.7±9.1 years. The mean clinical tumor size was 6.7 ± 1.4 cm; stage IliA that was presented in 32 patients (64%) and IIIB was presented in 18 patients (36%). Chemotherapy was given for a median of 4 cycles, there was reduction of the mean clinical tumor size from 6.7 ± 1.4 cm to 4.3 ± 2.7 cm (P 〈 0.001). Clinical response was complete in 5 (10%) tumors, complete pathological tumor response (post-neoadjuvant) was detected in 6 (16%) of patients. Complete clinical nodal response (post-neoadjuvant) in 23 (46%) axillae, on sonographic assessment of the axilla, response was complete in 17 (34%) axillae. Complete pathological nodal response occurred in 16 (32%) axillae. Out of 17 axillae that showed complete sonographic response 11 axillae showed complete pathological nodal response (P 〈 0.001). Conclusion: Formal axillary lymph node dissection can be avoided and replaced by SLNB post NACT in patients with L  相似文献   
27.
Background: Previously, subfascial ligation of perforator veins to treat venous ulceration in the lower extremities required long skin incisions through diseased skin and subcutaneous tissue. This was known as "the Linton operation." In 1985, Hauer described an endoscopic technique for ligating incompetent perforator veins; this seminal contribution marked the advent of subfascial endoscopic perforator surgery (SEPS). Methods: From 1996 to 1998, we prospectively collected data on 41 patients with chronic venous insufficiency (CVI) who underwent a SEPS procedure at our institution. Preoperative assessment consisted of color-flow duplex ultrasound scanning, as well as ascending and descending phlebography. Results: Some 45 SEPS procedures were performed on the 41 patients. Ages ranged from 42 to 84 years (mean, 60). Active venous ulcers were present in 37 legs; healing occurred within 9 weeks in 33 of them. No new ulcers developed in the follow-up period, a mean of 44 weeks. Conclusion: The results suggest that the SEPS procedure incorporated into the overall treatment plan for patients with CVI produces active healing with a minimum of postoperative complications. The study demonstrates the safety and efficiency of this procedure; it also underscores the important role incompetent perforator veins have in the formation of venous ulcers.  相似文献   
28.
29.
This investigation was undertaken to compare phenotypic and molecular methods for detection of carbapenemase-producing Pseudomonas aeruginosa. A total of 245 non-duplicated isolates of P. aeruginosa were collected from hospitalized patients. Disc diffusion method was used to identify carbapenem-resistant bacteria. Three phenotypic methods, including Modified Hodge Test (MHT), Modified Carba NP (MCNP) test and Carbapenem Inactivation Method (CIM) were used for investigation of carbapenemase production. In addition, polymerase chain reaction (PCR) was used to detect carbapenemase encoding genes. Of 245 P. aeruginosa isolates investigated, 121 isolates were carbapenem-resistant. Among carbapenem-resistant isolates, 40, 39 and 35 isolates exhibited positive results using MHT, MCNP test and CIM, respectively. PCR indicated the presence of carbapenemase genes in 35 of carbapenem-resistant isolates. MHT showed low sensitivity and specificity for carbapenemase detection among P. aeruginosa isolates in comparison to PCR. CIM was most affordable and highly specific than MCNP test compared with the molecular method.  相似文献   
30.
Background: It is not known how accommodative insufficiency influences reading performance. Methods: Reading eye movements were recorded before and after treatment for accommodative insufficiency in 12 school children (eight to 16 years). During the eight‐week treatment period all subjects wore a +1.00 D addition when reading. Results: Large variations in reading patterns were found. Despite successful accommodative treatment (p < 0.001), no correlation was found to suggest improved reading velocity. Discussion: Three case reports will be presented and the implications discussed.  相似文献   
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