Review of the Applications of Biomedical Compositions Containing Hydroxyapatite and Collagen Modified by Bioactive Components

Regenerative medicine is becoming a rapidly evolving technique in today’s biomedical progress scenario. Scientists around the world suggest the use of naturally synthesized biomaterials to repair and heal damaged cells. Hydroxyapatite (HAp) has the potential to replace drugs in biomedical engineering and regenerative drugs. HAp is easily biodegradable, biocompatible, and correlated with macromolecules, which facilitates their incorporation into inorganic materials. This review article provides extensive knowledge on HAp and collagen-containing compositions modified with drugs, bioactive components, metals, and selected nanoparticles. Such compositions consisting of HAp and collagen modified with various additives are used in a variety of biomedical applications such as bone tissue engineering, vascular transplantation, cartilage, and other implantable biomedical devices.     

Maternal humoral factors associated with perinatal human immunodeficiency virus type-1 transmission in a cohort from Kigali, Rwanda, 1988-1994

OBJECTIVES: to study different parameters of humoral immunity responses in the serum of 39 human immunodeficiency virus type-1 infected pregnant women from Kigali, (Rwanda) in correlation with perinatal transmission. METHODS: this study was done between 1988 and 1994. Thirty nine HIV-1 infected women, 18 transmitting (T) and 21 non-transmitting (NT) mothers, have been chosen based on the quantity of sera available for analysis. Maternal data were collected at the time of delivery or during the preceding month. Quantification of viral load was performed by the signal amplification bDNA assay. Specific reactivity of antibody was tested against recombinant p24 protein and five different synthetic peptides from gp120 and gp41 based on HIV LAI-strain sequences. Neutralization assays were performed against laboratory (RII strain of the HIV-1 C subtype) and primary strains (two NSI and one SI of the HIV-1 A subtype). Antibody Dependent Cellular Cytotoxicity assay was performed with CEM.NK(R) cells against a laboratory HIV-1 strain. RESULTS: absence of correlation regarding maternal viral load, or viral subtype and vertical transmission was observed. By contrast, the CD4/CD8 ratio was significantly higher in non-transmitting mothers compared to transmitting mothers. Moreover, high anti-p24 antibody avidity was correlated with a lower risk of perinatal transmission. Furthermore, transmission risk appeared significantly higher with reactivity of serum samples to linear epitopes of gp41 (amino acids 566-582, 578-594), whereas risk appeared lower with reactivity to the immunodominant domain of gp41 (amino acids 597-609). No significant difference was observed in titres of antibody neutralizing primary isolates (two NSI (non syncitium inducer) and one SI (syncitium inducer) of the HIV-1 A subtype) and laboratory strain (RII strain, of the HIV-1 C subtype) between transmitting and non-transmitting mother's sera. In addition, titres of Antibody Dependent Cellular Cytotoxicity were similar in transmitting versus non-transmitting mothers. However, high Antibody Dependent Cellular Cytotoxicity titres were correlated with a good clinical status of children. CONCLUSIONS: three parameters such as high CD4/CD8 ratio, high anti-p24 antibody avidity and high reactivity against the immunodominant epitope of gp41 have been shown to be correlated with no perinatal transmission. High Antibody Dependent Cellular Cytotoxicity titres appeared to be linked to a good clinical status of children after birth. One parameter, reactivity against two linear epitopes of gp41, appeared to be correlated with vertical transmission.     

The local immune phenotype influences prognosis in patients with nodal-positive rectal cancer after neoadjuvant chemoradiation

International Journal of Colorectal Disease - The local immune contexture in patients with locally advanced rectal cancer (LARC) has important prognostic value after neoadjuvant chemoradiation and...     

Comparison of Antigen Tests and qPCR in Rapid Diagnostics of Infections Caused by SARS-CoV-2 Virus

Diagnostics of the coronavirus disease 2019 (COVID-19) using molecular techniques from the collected respiratory swab specimens requires well-equipped laboratory and qualified personnel, also it needs several hours of waiting for results and is expensive. Antigen tests appear to be faster and cheaper but their sensitivity and specificity are debatable. The aim of this study was to compare a selected antigen test with quantitative polymerase chain reaction (qPCR) tests results. Nasopharyngeal swabs were collected from 192 patients with COVID-19 symptoms. All samples were tested using Vitassay qPCR SARS-CoV-2 kit and the Humasis COVID-19 Ag Test (MedSun) antigen immunochromatographic test simultaneously. Ultimately, 189 samples were tested; 3 samples were excluded due to errors in taking swabs. The qPCR and antigen test results were as follows: 47 positive and 142 negative, and 45 positive and 144 negative, respectively. Calculated sensitivity of 91.5% and specificity of 98.6% for the antigen test shows differences which are not statistically significant in comparison to qPCR. Our study showed that effectiveness of the antigen tests in rapid laboratory diagnostics is high enough to be an alternative and support for nucleic acid amplification tests (NAAT) in the virus replication phase in the course of COVID-19.     

Hyaluronic acid skin fillers: Adverse reactions and skin testing

BACKGROUND: Hyaluronic acid (HA) fillers have been proposed as alternatives to other temporary skin fillers, such as bovine collagen, for treating facial skin lines and for providing lip augmentation. Several types of commercial HA fillers are now available in many countries. They include Restylane, which is produced by microbiologic engineering techniques, and Hylaform, which is HA extract derived from rooster combs. They have been approved for use in several countries, but not currently in the United States. There are no recommendations to perform pretreatment skin testing by the manufacturers. OBJECTIVE: Our purpose is to describe and comment on our experiences with Hylaform and Restylane fillers. Observation of any side effects and skin testing results were documented. METHODS: Between September 1996 and September 2000, 709 patients were treated with Hylaform and Restylane and were followed up clinically for at least 1 year. Three of these patients (0.42%) developed delayed skin reactions. Three other patients were referred for evaluation of their skin reactions from other practitioners. Five of these 6 patients agreed to skin testing of their forearms. RESULTS: In the 5 patients tested, challenge intradermal skin testing was positive in 4 patients; the reactions started approximately 8 weeks after injection. CONCLUSIONS: There was a slight incidence of delayed inflammatory skin reactions to two HA fillers. Both of these reactions occurred after the first and repeat injections. Challenge skin testing was positive in 4 of 5 tested patients.     

宫颈癌患者 Kruppel 样因子 6，p21 蛋白表达水平与病理特征及化疗敏感性的相关性分析

目的　探讨宫颈癌患者 Kruppel 样因子 6（KLF6）,p21 蛋白表达水平与病理特征及化疗敏感性的相关性。方法　回顾性分析 2016 年 1 月 ~2018 年 12 月接受化疗的 40 例宫颈癌患者,化疗结束后根据化疗效果将患者分为化疗敏感组（CR+PR）、化疗抵抗组（SD+PD）。采用免疫组化检测宫颈癌组织 KLF6,p21 蛋白的表达,分析其与临床病理特征、化疗敏感性及总生存期（OS）的关系。结果　宫颈癌中 KLF6,p21 蛋白阳性率与病理分期、肿瘤直径、分化类型及化疗敏感性相关（χ 2 =2.14~5.74,均 P<0.05）。KLF6+/p21- 者 ORR 为 85.71%,显著高于非 KLF6+/p21- 者 42.11%（χ 2 =8.33,P<0.05）。宫颈癌患者的中位 OS 为 11.20 个月（95%CI: 9.73~12.71）,其中 KLF6 阳性者中位 OS 为 11.90个月（95%CI: 10.81~12.99）,显著高于阴性表达者 9.20 个月（95%CI: 9.05~9.35）;p21 蛋白阳性者中位 OS 为 9.14 个月（95%CI: 8.26~10.22）,显著低于 p21 阴性表达者 11.62 个月（95%CI: 9.63~13.58）（χ 2 =11.50,6.23,均 P<0.05）。结论　宫颈癌患者 KLF6,p21 表达水平与其临床病理特征相关。KLF6 高表达、p21 低表达者化疗敏感性高,且预后更好,可作为预后、个体化治疗方案选择的评价指标。     

系统性硬化症肺部受累的胸部高分辨力CT表现特点分析

目的分析系统性硬化症（SSc）肺部受累时胸部高分辨力计算机体层摄影术（HRCT）表现,提高对SSc肺部损害的认识。方法选择2009年1月~2012年6月明确诊断的45例SSc患者,其中男性9例,女性36例;年龄为20~80岁,平均年龄58.50岁。回顾其胸部HRCT表现,并进行HRCT评分,对其胸部HRCT特点进行总结分析。结果胸部HRCT证实,存在间质性肺疾病患者为32例（71.1%）,其中34.4%患者（11/32）无呼吸系统症状。SSc肺部受累在HRCT图像上以磨玻璃影（81.3%）和网格影（56.3%）最为常见,分布以双下肺（71.9%）及胸膜下分布（81.3%）为主。对两侧的上中下肺野的HRCT评分进行t检验发现双侧病变差异无统计学意义（P〉0.05）,呈对称性分布。对上中下肺野的HRCT评分进行两两比较,下肺野受累最明显,中野次之,上野受累最少（P〈0.05）。在存在肺间质受累的患者中,弥漫型患者的HRCT评分（8.82±5.56）与局限型患者的评分（8.73±5.61）间差异无统计学意义（P〉0.05）。肺外胸部脏器受累包括肺动脉增宽、胸膜病变、心包积液、纵隔淋巴结肿大、食管扩张。肺动脉增宽33.3%（15/45）,弥漫型患者中肺动脉增宽的发生率与局限型患者的发生率差异无统计学意义;有雷诺现象者的肺动脉增宽的发生率高（15/34 vs 0/11;P=0.005）。结论胸部HRCT对SSs的肺、胸膜、食道、肺动脉的评估均有较高价值,其中肺间质受累是最为常见的,对称性分布、双下肺突出的间质性病变为其主要特点。     

Inhibition of methylprednisolone elimination in the presence of clarithromycin therapy

BACKGROUND: Macrolide antibiotics have long been used as steroid-sparing agents in patients with severe steroid-dependent asthma. Their efficacy and their propensity to potentiate glucocorticoid adverse effects have been attributed in part to their ability to delay glucocorticoid clearance. OBJECTIVE: We sought to determine whether clarithromycin, a newer macrolide antibiotic, can alter the pharmacokinetic profile of oral glucocorticoids and thereby increase the risk of steroid-induced adverse effects. METHODS: An open-label study in a paired design (before and after treatment) was conducted in a hospital-based outpatient clinic. Participants were 6 adult patients (mean age, 30 years) with mild-to-moderate asthma. Prednisone (40 mg/1.73 m2) and methylprednisolone (40 mg/1.73 m2) were given as single randomized doses on consecutive study days before and on days 8 and 9 of a clarithromycin (500 mg twice daily) course. Twelve-hour pharmacokinetic profiles with measurement of plasma methylprednisolone and prednisolone levels were taken before and after clarithromycin therapy. RESULTS: Clarithromycin therapy resulted in a 65% reduction of methylprednisolone clearance and significantly higher mean plasma methylprednisolone concentrations compared with preclarithromycin concentrations but had no significant effect on prednisolone clearance or mean prednisolone plasma concentrations. CONCLUSIONS: Clinicians must be aware of potential drug interactions that could place patients at increased risk for steroid-induced adverse effects. Such an effect has been demonstrated between clarithromycin and methylprednisolone, two drugs that may be administered concomitantly in asthma. To avoid potential steroid-enhancing effects, prednisone should be substituted for methylprednisolone during prolonged courses of clarithromycin therapy.