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151.
Eduardo D. Rodríguez-Aguilar Jesús Martínez-Barnetche Cesar R. Gonzlez-Bonilla Juan M. Tellez-Sosa Rocío Argotte-Ramos Mario H. Rodríguez 《Viruses》2022,14(1)
Chikungunya virus (CHIKV) is an alphavirus transmitted by Aedes mosquitoes, which causes Chikungunya fever. Three CHIKV genotypes have been identified: West African, East-Central-South African and Asian. In 2014, CHIKV was detected for the first time in Mexico, accumulating 13,569 confirmed cases in the following three years. Studies on the molecular diversification of CHIKV in Mexico focused on limited geographic regions or investigated only one structural gene of the virus. To describe the dynamics of this outbreak, we analyzed 309 serum samples from CHIKV acute clinical cases from 15 Mexican states. Partial NSP3, E1, and E2 genes were sequenced, mutations were identified, and their genetic variability was estimated. The evolutionary relationship with CHIKV sequences sampled globally were analyzed. Our sequences grouped with the Asian genotype within the Caribbean lineage, suggesting that the Asian was the only circulating genotype during the outbreak. Three non-synonymous mutations (E2 S248F and NSP3 A437T and L451F) were present in our sequences, which were also identified in sequences of the Caribbean lineage and in one Philippine sequence. Based on the phylogeographic analysis, the viral spread was reconstructed, suggesting that after the introduction through the Mexican southern border (Chiapas), CHIKV dispersed to neighboring states before reaching the center and north of the country through the Pacific Ocean states and Quintana Roo. This is the first viral phylogeographic reconstruction in Mexico characterizing the CHIKV outbreak across the country. 相似文献
152.
At Hines VA Hospital, three out of 38 cardiac transplant patients, who were 9, 10, and 14 mo post-surgery and treated with immunosuppressive drugs, including OKT3 prophylaxis for acute rejection, developed a solitary pulmonary nodule. Fine-needle aspiration biopsy of the nodules in these three patients revealed a hypercellular, monotonous population of large lymphoid cells. These abnormal cells were isolated, with small aggregates occasionally seen. the nuclear membranes were irregular, the chromatin was finely granular, nucleoli were prominent, and mitotic figures were frequently noted. The cells were immunoreactive to leukocyte common antigen and B-lymphocyte. Lambda light chain immunoglobulin was positive in one case, kappa in the second case, and neither light chains in the third patient. By electron microscopy in one case, the cells were large immature lymphoid cells with immunoblastic features. Subsequent tissue studies, complemented by frozen section immunostaining, flow cytometry, and phenotyping, reaffirmed the diagnosis of malignant lymphoma. It appears that OKT3 therapy increases several fold the risk of lymphoma's developing in cardiac transplant patients. Preliminary published reports have also recommended close surveillance of patients receiving OKT3 for early indications of lymphoproliferative disorder and a reevaluation of the risk vs. benefit for the prophylatic use of OKT3. 相似文献
153.
Extraction of La(iii), Eu(iii) and Fe(iii) was compared in n-dodecane and two ionic liquids (ILs) (1-ethyl-1-butylpiperidinium bis (trifluoromethylsulfonyl)imide [EBPip+] [NTf2−] and 1-ethyl-1-octylpiperidinium bis (trifluoromethylsulfonyl)imide [EOPip+] [NTf2−]). Using the extractant N,N′-dimethyl-N,N′-dioctylhexylethoxymalonamide (DMDOHEMA), the effect of pH was investigated in detail to recover extraction mechanisms. The use of ILs as the organic solvent instead of n-dodecane, greatly enhances extraction efficiency, and an ionic liquid with a shorter alkyl chain [EBPip+] [NTf2−] provides higher extraction than [EOPip+] [NTf2−]. The mechanistic study points out that for low nitric acid concentrations ([HNO3] ≤ 0.01 M), metal is extracted via a cation of the ionic liquids, while for higher nitric acid concentrations ([HNO3] ≥ 1.0 M), extraction occurs through pure solvation mechanism of DMDOHEMA as in conventional diluents. This latter case is of high interest for applications, as higher extraction can be obtained without any loss of ILs by ion exchange mechanisms.Extraction of La(iii), Eu(iii) and Fe(iii) was compared in n-dodecane and in two ionic liquids (ILs) [EBPip+] [NTf2−] and [EOPip+] [NTf2−]. Extraction mechanisms have been investigated as a function of pH. 相似文献
154.
Zhenhong Qu Cesar Hernandez Garcia Leslie M. O'Rourke Stephen R. Planck Manoj Kohli James T. Rosenbaum 《Arthritis \u0026amp; Rheumatology》1994,37(2):212-220
Objective. To test the hypothesis that local proliferation contributes significantly to the hyperplasia of rheumatoid synovium. Methods. Immunohistologic and chemical staining was used to identify 3 markers of cell proliferation: proliferating cell nuclear antigen, c-myc proto-oncogene, and nucleolar organizer regions. Synovium from 21 patients with rheumatoid arthritis, 34 with degenerative joint disease, and 7 with joint trauma was examined. Results. All 3 markers indicated substantial, active proliferation of synovial lining cells in synovium with hyperplasia. Proliferating cells showed type I procollagen immunoreactivity but were negative for CD68, a monocyte/macrophage marker. Proliferation was greater in rheumatoid arthritis than in the other conditions evaluated. Conclusion. In situ proliferation of fibroblast-like synoviocytes in the synovium lining contributes considerably to the increase in cell numbers in rheumatoid synovium. 相似文献
155.
Mesenchymal stem cell therapy alleviates the neuroinflammation associated with acquired brain injury
Brooke Bonsack Sydney Corey Alex Shear Matt Heyck Blaise Cozene Nadia Sadanandan Henry Zhang Bella Gonzales‐Portillo Michael Sheyner Cesar V. Borlongan 《CNS Neuroscience & Therapeutics》2020,26(6):603-615
Ischemic stroke and traumatic brain injury (TBI) comprise two particularly prevalent and costly examples of acquired brain injury (ABI). Following stroke or TBI, primary cell death and secondary cell death closely model disease progression and worsen outcomes. Mounting evidence indicates that long‐term neuroinflammation extensively exacerbates the secondary deterioration of brain structure and function. Due to their immunomodulatory and regenerative properties, mesenchymal stem cell transplants have emerged as a promising approach to treating this facet of stroke and TBI pathology. In this review, we summarize the classification of cell death in ABI and discuss the prominent role of inflammation. We then consider the efficacy of bone marrow–derived mesenchymal stem/stromal cell (BM‐MSC) transplantation as a therapy for these injuries. Finally, we examine recent laboratory and clinical studies utilizing transplanted BM‐MSCs as antiinflammatory and neurorestorative treatments for stroke and TBI. Clinical trials of BM‐MSC transplants for stroke and TBI support their promising protective and regenerative properties. Future research is needed to allow for better comparison among trials and to elaborate on the emerging area of cell‐based combination treatments. 相似文献
156.
Cleverton Cesar Spautz MSc Eduardo Schunemann Junior MSc Lucas Roskamp Budel MD Tereza Cristina Santos Cavalcanti PhD Maria Helena Louveira PhD Plinio Gasperin Junior PhD Leonardo Paese Nissen MD Bernardo Passos Sobreiro PhD Maíra Teixeira Dória MSc Cicero Andrade Urban PhD Vinicius Milani Budel PhD 《Journal of surgical oncology》2020,122(2):164-169
157.
158.
JC Borel S Gakwaya JF Masse CA Melo-Silva F Sériès 《Respiratory physiology & neurobiology》2012,183(2):170-176
Oronasal mask (ONM) can be used when mouth leaks impair nasal-CPAP effectiveness. However, ONM's constraint on the chin and straps' traction may alter upper airway (UA) mechanical properties. In contrast, mandibular advancement device associated with nasal-CPAP (NM+MAD) may reduce UA resistance. The aim of this exploratory study was to compare the effects of ONM, NM, and NM+MAD on UA mechanical properties. The three interface modalities were assessed in 11 OSAS patients at 6, 8, 10cmH(2)O CPAP using a phrenic nerve magnetic stimulation (PNMS) protocol. PNMS-twitches' related flow, pharyngeal pressures (nasopharynx, velopharynx, oropharynx) and UA resistances were determined. Regardless of CPAP level, twitch-induced maximum flow was higher with NM+MAD than with ONM. Velopharyngeal resistance was higher with ONM than with NM+MAD. Oropharyngeal resistance was higher with ONM than with NM. In conclusion, NM+MAD reduced velopharyngeal resistance compared to those measured with ONM and NM alone. We hypothesize that this strategy may help reducing the effective pressure level and thus further limit the risk for mouth leaks. 相似文献
159.
160.
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