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101.
Beu P. Oropeza Carlos Serna III Michael E. Furth Luis H. Solis Cesar E. Gonzalez Valeria Altamirano Daisy C. Alvarado Jesus A. Castor Jesus A. Cedeno Dante Chaparro Vega Octavio Cordova Isaac G. Deaguero Erwin I. Delgado Mario F. Garcia Duarte Mirsa Gonzalez Favela Alba J. Leyva Marquez Emilio S. Loera Gisela Lopez Fernanda Lugo Tania G. Miramontes Erik Munoz Paola A. Rodriguez Leila M. Subia Arahim A. Zuniga Herrera Thomas Boland 《Materials》2022,15(13)
The rapidly growing field of tissue engineering hopes to soon address the shortage of transplantable tissues, allowing for precise control and fabrication that could be made for each specific patient. The protocols currently in place to print large-scale tissues have yet to address the main challenge of nutritional deficiencies in the central areas of the engineered tissue, causing necrosis deep within and rendering it ineffective. Bioprinted microvasculature has been proposed to encourage angiogenesis and facilitate the mobility of oxygen and nutrients throughout the engineered tissue. An implant made via an inkjet printing process containing human microvascular endothelial cells was placed in both B17-SCID and NSG-SGM3 animal models to determine the rate of angiogenesis and degree of cell survival. The implantable tissues were made using a combination of alginate and gelatin type B; all implants were printed via previously published procedures using a modified HP inkjet printer. Histopathological results show a dramatic increase in the average microvasculature formation for mice that received the printed constructs within the implant area when compared to the manual and control implants, indicating inkjet bioprinting technology can be effectively used for vascularization of engineered tissues. 相似文献
102.
Rationale:To report a rare case of calculating the IOL power in a cataract patient who underwent both radial keratotomy (RK) and photorefractive keratectomy (PRK).Patient concerns:A 48-year-old woman underwent bilateral RK at age 22 and bilateral PRK at age 46. She developed bilateral corneal haze and corneal endothelial inflammation and received steroids therapy for long time after PRK. Then she was referred to our hospital due to decreased vision in the both eyes.Diagnoses:The patient was diagnosed with binocular complicated cataract, corneal haze, high myopia and post corneal refractive surgery (RK and PRK).Interventions:The patient underwent bilateral phacoemulsification. The IOL power was calculated using SRK/T formula for RK and Haigis-L formula for PRK, respectively. We finally selected the Haigis-L formula and the intraocular lens (SN60WF) was implanted within the capsular bag.Outcomes:After the surgery, both eyes showed myopia drift, and the right eye continuously fluctuated in refractive results. However, by nearly 1 year later, refractive results in both eyes had stabilized, and no other complications had occurred.Lessons:IOL power in patients who undergo both RK and PRK can be reliably calculated using the Shammas-PL, Average of multiple formulas, or Barret True-K No History formulas. Haigis-L formula is not suitable. Such patients require at least three months after surgery to attain refractive stability in both eyes. 相似文献
103.
The high-dose glucocorticosteroid (GC) treatment is the first choice for dermatomyositis complicated with interstitial lung disease (DM-ILD) but patients are resistant to the high-dose GC monotherapy. Besides, the high dose of GC, the secondary immunosuppressive agent(s) is necessary but there is controversy for the selection of immunosuppressive agent(s). The objectives of the study were to analyze the efficacy of different therapeutic options for DM-ILD to identify the optimal therapy. A total of 60 patients had received intravenous 1.0–2.0 mg/ kg/day prednisolone for DM-ILD. In severe conditions, patients had received oral 1 to 3 mg/day tacrolimus (TAC), 500 mg/ m2/month cyclophosphamide (CY), and/or 1 g/ day methylprednisolone pulse (TI cohort, n = 24). In severe conditions, patients had received 1 g/day methylprednisolone pulse and 2–3 mg/ kg/day cyclosporine A (CsA) and/or 500 mg/ m2/month CY (existing historical treatment; CT cohort, n = 36). Patients of the TI cohort did not receive CsA. Patients in the CT cohort were received CY in significantly fewer numbers than those of the TI cohort during treatment (P = .0112). A total of 11 (46%) patients from the TI cohort and 14 (39%) patients from the CT cohort were developed relapsed. At the end of the 30-months, higher numbers of patients of the TI cohort had an event(s) free survival than those of the CT cohort (7 (29%) vs 2 (6%), P = .0229). Also, higher numbers of patients of the TI cohort had survived irrespective of an event(s) than those of the CT cohort (21 (87%) vs 22 (61%), P = .0399). Patients of the TI cohort had developed herpes zoster (2 (8%)) and cytomegalovirus (4 (17%)) infections. Patients of the CT cohort developed renal dysfunction (10 (28%)). Hyperglycemia, hyperlipidemia, and fracture (GC-related toxicities) were also reported in both cohorts and these toxicities were fever in the TI cohort. The addition of TAC to high doses GC with CY is an ideal treatment for severe conditions of DM-ILD (Level of Evidence: III; Technical Efficacy Stage: 4). 相似文献
104.
测定胃癌患者肿瘤组织与外周血中前列腺素E2的临床意义 总被引:4,自引:0,他引:4
目的 测定胃癌患者肿瘤组织及外周血中前列腺素E2(prostaglandin E2,PGE2)含量.方法 用PGE2酶联免疫试剂盒分别测定40例胃癌患者肿瘤组织、癌旁切缘组织及术前外周血中PGE2含量.结果 胃癌组织的PGE2含量明显高于癌旁切缘组织,分别为(8.225±2.425)、(1.669±0.287)ng/g,两者差异有统计学意义(P<0.01),低分化和高中分化胃癌组织PGE2含量分别为(9.02±2.28)、(5.38±0.35)ng/g,两者有显著性差异(P<0.05).外周血中PGE2含量与胃癌组织PGE2含量呈正相关(r=0.889,P<0.01).肿瘤直径≥5 cm和<5 cm的胃癌患者外周血中PGE2含量差异有统计学意义(P<0.05).低分化和高中分化胃癌患者外周血中PGE2含量差异也有统计学意义(P<0.05).胃癌组织及外周血中PGE2含量与患者年龄、性别无关,与肿瘤部位、浸润深度、临床病理分期及是否淋巴结转移也无关.结论 胃癌患者肿瘤组织中PGE2含量增高,其外周血PGE2含量也随之增高,表明外周血PGE:水平与胃癌组织释放的PGE2含量成正比.测定外周血中PGE2可以间接评估胃癌患者的肿瘤大小与分化程度. 相似文献
105.
Talamini R Vaccarella S Barbone F Tavani A La Vecchia C Herrero R Muñoz N Franceschi S 《British journal of cancer》2000,83(9):1238-1242
In an Italian case-control study of oral cancer, number of missing teeth and other aspects of dental care were similar, but the general condition of the mouth, as indicated by gum bleeding, tartar deposits and mucosal irritation, was worse among oral cancer cases than controls. No differences were detected in sexual practices (including oral sex) and (previous) sexually transmitted infections. 相似文献
106.
107.
Delmanto A Nahas-Neto J Nahas EA de Oliveira ML Fernandes CE Traiman P 《European journal of obstetrics, gynecology, and reproductive biology》2008,139(2):187-192
OBJECTIVE: The objective was to analyze the effect of raloxifene on the vaginal epithelium of postmenopausal women. STUDY DESIGN: In this non-randomized clinical trial, 80 women (mean age = 60.6 years) were prospectively studied. Forty patients received 60 mg/day of raloxifene (RG), and 40 women constituted a non-treated control group (CG), paired by age and time since menopause. The treated group consisted of patients with osteoporosis of the lumbar spine. Those with a diagnosis of infection in the lower genital tract and using hormone therapy (HT) up to 6 months prior to the study were excluded. Vaginal smears were collected at baseline and after 6 months of intervention. The vaginal maturation value (VMV) was determined, and counts of superficial, intermediate and parabasal cells were performed. Smears were analyzed by only one cytopathologist who was blinded to patient data. The t-test, Wilcoxon test, and Chi-Squared test were used in the statistical analysis. RESULTS: The study groups were homogeneous regarding age, time since menopause, parity, HT use, smoking, and body mass index. No statistically significant differences were observed in VMV median values (RG, 39.7 and 35.7; CG, 50.0 and 50.0, respectively) or in the percentage of superficial, intermediate and parabasal cells between the groups at baseline and after 6 months (p>0.05). There was no significant correlation between VMV and age, time since menopause, previous HT use, or body mass index, in either of the groups. CONCLUSION: Treatment with raloxifene for 6 months has no effect on the maturation of the vaginal epithelium in postmenopausal women with osteoporosis. 相似文献
108.
Dedifferentiated liposarcoma (DDLPS) is a rare subtype of liposarcoma with a poor prognosis. This current case report describes a rectal DDLPS in a 68-year-old Chinese male that presented with lower abdominal pain and weight loss. Computed tomography and magnetic resonance imaging were undertaken to evaluate the tumour. The patient underwent radical resection of the rectal tumour, sigmoid colostomy and partial ureterectomy. The tumour was positive for mouse double minute 2 by immunohistochemistry. The patient healed well but refused chemotherapy postoperatively for economic reasons. The tumour recurred and metastasized 4 weeks after the operation. After relevant treatment, the patient''s condition deteriorated and he died of shock, metabolic acidosis, hyperlactataemia and acute renal failure. The case report also reviews the literature in terms of the clinical diagnosis, treatment and pathological characteristics of rectal DDLPS with the aim of improving the level of diagnosis and treatment. 相似文献
109.
Chao Zhang Anurag Verma Yuanqing Feng Marcelo C. R. Melo Michael McQuillan Matthew Hansen Anastasia Lucas Joseph Park Alessia Ranciaro Simon Thompson Meagan A. Rubel Michael C. Campbell William Beggs Jibril Hirbo Sununguko Wata Mpoloka Gaonyadiwe George Mokone Regeneron Genetic Center Thomas Nyambo Dawit Wolde Meskel Gurja Belay Charles Fokunang Alfred K. Njamnshi Sabah A. Omar Scott M. Williams Daniel J. Rader Marylyn D. Ritchie Cesar de la Fuente-Nunez Giorgio Sirugo Sarah A. Tishkoff 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(21)
Human genomic diversity has been shaped by both ancient and ongoing challenges from viruses. The current coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has had a devastating impact on population health. However, genetic diversity and evolutionary forces impacting host genes related to SARS-CoV-2 infection are not well understood. We investigated global patterns of genetic variation and signatures of natural selection at host genes relevant to SARS-CoV-2 infection (angiotensin converting enzyme 2 [ACE2], transmembrane protease serine 2 [TMPRSS2], dipeptidyl peptidase 4 [DPP4], and lymphocyte antigen 6 complex locus E [LY6E]). We analyzed data from 2,012 ethnically diverse Africans and 15,977 individuals of European and African ancestry with electronic health records and integrated with global data from the 1000 Genomes Project. At ACE2, we identified 41 nonsynonymous variants that were rare in most populations, several of which impact protein function. However, three nonsynonymous variants (rs138390800, rs147311723, and rs145437639) were common among central African hunter-gatherers from Cameroon (minor allele frequency 0.083 to 0.164) and are on haplotypes that exhibit signatures of positive selection. We identify signatures of selection impacting variation at regulatory regions influencing ACE2 expression in multiple African populations. At TMPRSS2, we identified 13 amino acid changes that are adaptive and specific to the human lineage compared with the chimpanzee genome. Genetic variants that are targets of natural selection are associated with clinical phenotypes common in patients with COVID-19. Our study provides insights into global variation at host genes related to SARS-CoV-2 infection, which have been shaped by natural selection in some populations, possibly due to prior viral infections.Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Coronaviruses are enveloped, positive-sense, and single-stranded RNA viruses, many of which are zoonotic pathogens that crossed over into humans. Seven coronavirus species, including SARS-CoV-2, have been discovered that, depending on the virus and host physiological condition, may cause mild or lethal respiratory disease. There is considerable variation in disease prevalence and severity across populations and communities. Importantly, minority populations in the United States appear to have been disproportionally affected by COVID-19 (1, 2). For example, in Chicago, more than 50% of COVID-19 cases and nearly 70% of COVID-19 deaths are in African Americans (who make up 30% of the population of Chicago) (1). While social and economic factors are largely responsible for driving COVID-19 health disparities, investigating genetic diversity at host genes related to SARS-CoV-2 infection could help identify functionally important variation, which may play a role in individual risk for severe COVID-19 infection.In this study, we focused on four key genes playing a role in SARS-CoV-2 infection (3). The ACE2 gene, encoding the angiotensin-converting enzyme-2 protein, was reported to be a main binding site for severe acute respiratory syndrome coronavirus (SARS-CoV) during an outbreak in 2003, and evidence showed stronger binding affinity to SARS-CoV-2, which enters the target cells via ACE2 receptors (3, 4). The ACE2 gene is located on the X chromosome (chrX); its expression level varies among populations (5); and it is ubiquitously expressed in the lung, blood vessels, gut, kidney, testis, and brain, all organs that appear to be affected as part of the COVID-19 clinical spectrum (6). SARS-CoV-2 infects cells through a membrane fusion mechanism, which in the case of SARS-CoV, is known to induce down-regulation of ACE2 (7). Such down-regulation has been shown to cause inefficient counteraction of angiotensin II effects, leading to enhanced pulmonary inflammation and intravascular coagulation (7). Additionally, altered expression of ACE2 has been associated with cardiovascular and cerebrovascular disease, which is highly relevant to COVID-19 as several cardiovascular conditions are associated with severe disease. TMPRSS2, located on the outer membrane of host target cells, binds to and cleaves ACE2, resulting in activation of spike proteins on the viral envelope and facilitating membrane fusion and endocytosis (8). Two additional genes, DPP4 and LY6E, have been shown to play an important role in the entry of SARS-CoV-2 virus into host cells. DPP4 is a known functional receptor for the Middle East respiratory syndrome coronavirus (MERS-CoV), causing a severe respiratory illness with high mortality (9, 10). LY6E encodes a glycosylphosphatidylinositol-anchored cell surface protein, which is a critical antiviral immune effector that controls coronavirus infection and pathogenesis (11). Mice lacking LY6E in hematopoietic cells were susceptible to murine coronavirus infection (11).Previous studies of genetic diversity at ACE2 and TMPRSS2 in global human populations did not include an extensive set of African populations (5, 12–14). No common coding variants (defined here as minor allele frequency [MAF] > 0.05) at ACE2 were identified in any prior population studies. However, few studies included diverse indigenous African populations whose genomes harbor the greatest diversity among humans. This leads to a substantial disparity in the representation of African ancestries in human genetic studies of COVID-19, impeding health equity as the transferability of findings based on non-African ancestries to African populations can be low (15). Including more African populations in studying the genetic diversity of genes involved in SARS-CoV-2 infection is extremely necessary. Additionally, the evolutionary forces underlying global patterns of genetic diversity at host genes related to SARS-CoV-2 infection are not well understood. Using methods to detect natural selection signatures at host genes related to viral infections helps identify putatively functional variants that could play a role in disease risk.We characterized genetic variation and studied natural selection signatures at ACE2, TMPRSS2, DPP4, and LY6E in ethnically diverse human populations by analyzing 2,012 genomes from ethnically diverse Africans (referred to as the “African diversity” dataset), 2,504 genomes from the 1000 Genomes Project (1KG), and whole-exome sequencing of 15,977 individuals of European ancestry (EA) and African ancestry from the Penn Medicine BioBank (PMBB) dataset (SI Appendix, Fig. S1). The African diversity dataset includes populations with diverse subsistence patterns (hunter-gatherers, pastoralists, agriculturalists) and speaking languages belonging to the four major language families in Africa (Khoesan; Niger–Congo, of which Bantu is the largest subfamily; Afroasiatic; and Nilo-Saharan). We identify functionally relevant variation, compare the patterns of variation across global populations, and provide insight into the evolutionary forces underlying these patterns of genetic variation. In addition, we perform an association study using the variants identified from whole-exome sequencing at the four genes and clinical traits derived from electronic health record (EHR) data linked to the subjects enrolled in the PMBB. The EHR data include diseases related to organ dysfunctions associated with severe COVID-19, such as respiratory, cardiovascular, liver, and renal complications. Our study of genetic variation in genes involved in SARS-CoV-2 infection provides data to investigate infection susceptibility within and between populations and indicates that variants in these genes may play a role in comorbidities relevant to COVID-19 severity. 相似文献
110.
Jun Li Ting Zhao Jing Li Jiechen Shen Li Jia Bojing Zhu Liuyi Dang Chen Ma Didi Liu Fan Mu Liangshuo Hu Shisheng Sun 《Molecular oncology》2022,16(11):2135
Primary liver cancer, mainly comprising hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC), remains a major global health problem. Although ICC is clinically different from HCC, their molecular differences are still largely unclear. In this study, precision N‐glycoproteomic analysis was performed on both ICC and HCC tumors as well as paracancer tissues to investigate their aberrant site‐specific N‐glycosylation. By using our newly developed glycoproteomic methods and novel algorithm, termed ‘StrucGP’, a total of 486 N‐glycan structures attached on 1235 glycosites were identified from 894 glycoproteins in ICC and HCC tumors. Notably, glycans with uncommon LacdiNAc (GalNAcβ1‐4GlcNAc) structures were distinguished from their isomeric glycans. In addition to several bi‐antennary and/or bisecting glycans that were commonly elevated in ICC and HCC, a number of LacdiNAc‐containing, tri‐antennary, and core‐fucosylated glycans were uniquely increased in ICC. More interestingly, almost all LacdiNAc‐containing N‐glycopeptides were enhanced in ICC tumor but not in HCC tumor, and this phenomenon was further confirmed by lectin histochemistry and the high expression of β1‐4 GalNAc transferases in ICC at both mRNA and protein expression levels. The novel N‐glycan alterations uniquely detected in ICC provide a valuable resource for future studies regarding to the discovery of ICC diagnostic biomarkers, therapeutic targets, and mechanism investigations. 相似文献