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31.
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BackgroundThis study aimed to offer key features to differentiate scrub typhus (ST) and murine typhus (MT) at the early stage of the diseases and provide clinicoepidemiologic characteristics of ST and MT in southern Taiwan, a region where both diseases are endemic. Comparison of doxycycline treatment efficacy between the two diseases by matching disease severity and delayed treatment had never been investigated.MethodsWe reviewed the medical records of cases of ST and MT in four hospitals in southern Taiwan. Propensity-score matching was used to analyze the defervescence curves between patients with doxycycline-treated ST and MT by log-rank test.ResultsBetween 2004 and 2016, 265 ST and 63 MT cases were diagnosed. The number of cases of ST was significantly related to temperature (Rs = 0.77) and rainfall (Rs = 0.63). Island area exposure, arthropod bite, eschar, and lymphadenopathy were only recorded in ST patients. Multivariate analysis revealed that mountainous area exposure (odds ratio [OR], 11.0; 95% confidence interval [CI], 4.4–27.2) was an independent predictor for ST, while contact with rats (OR, 8.4; 95% CI, 3.3–21.3) was that for MT. After propensity-score matching, there was no difference in defervescence curves between these two rickettsioses treated with doxycycline (p = 0.24).ConclusionIn the present study, island area exposure, arthropod bite, eschar, and lymphadenopathy were unique manifestations of ST. Mountainous area exposure is a predictive factor for ST, while contact with rats predicted MT. There was no difference in defervescence time between these two rickettsioses after doxycycline treatment.  相似文献   
33.
We provide images of the entire central nervous system vasculature, and compare the anatomical findings in six different laboratory animals. A detailed understanding of the specific anatomy for each is important in the design of experimental modeling and for understanding the specific function of each target organ . Six different types of animals, the Korean wild mouse, C57BL/6J mouse, F344 rat, mongolian gerbil, Syrian hamsters, and guinea pigs, were included. To stain the blood vessels in each of the animals, Alcian blue reagent was used to perfuse each species. The bifurcation and anastomotic patterns of the anterior cerebral arteries differed in each species. The vascular supply to the olfactory nerve was visualized as a single artery supplying both olfactory nerves, and arteries supplying the lateral portion of the olfactory nerves originating from the olfactory bulb area. The posterior communicating arteries of the six animals demonstrated unique morphologies. The shape of the hypophyseal portal system varied by species. Most animals used in this study had a hexagonal Circle of Willis, except for the Korean wild mouse. Using this approach, we successfully mapped the brain vascular system in six different species of animals. This information and the images created can guide other researchers as they design research studies and create experimental models for new surgical procedures and approaches. Anat Rec, 2019. © 2019 Wiley Periodicals, Inc. Anat Rec, 302:2049–2061, 2019. © 2019 American Association for Anatomy  相似文献   
34.
Cytosine base editors (CBEs) and adenine base editors (ABEs), which are generally composed of an engineered deaminase and a catalytically impaired CRISPR‐Cas9 variant, are new favorite tools for single base substitution in cells and organisms. In this review, we summarize the principle of base‐editing systems and elaborate on the evolution of different platforms of CBEs and ABEs, including their deaminase, Cas9 variants, and editing outcomes. Moreover, we highlight their applications in mouse and human cells and discuss the challenges and prospects of base editors. The ABE‐ and CBE systems have been used in gene silencing, pathogenic gene correction, and functional genetic screening. Single base editing is becoming a new promising genetic tool in biomedical research and gene therapy.  相似文献   
35.
BackgroundFluoroquinolones are a popular alternative to trimethoprim-sulfamethoxazole for Stenotrophomonas maltophilia infections.ObjectivesTo compare the effects of fluoroquinolones and trimethoprim-sulfamethoxazole on mortality of S. maltophilia infections.Data sourcesPubMed and EMBASE.Study eligibility criteriaClinical studies reporting mortality outcomes of S. maltophilia infections.ParticipantsPatients with clinical infections caused by S. maltophilia.InterventionsFluoroquinolone monotherapy in comparison with trimethoprim-sulfamethoxazole monotherapy.MethodsSystematic review with meta-analysis technique.ResultsSeven retrospective cohort and seven case–control studies were included. Three cohort studies were designed to compare the two drugs, whereas others had other purposes. A total of 663 patients were identified, 332 of which were treated with trimethoprim-sulfamethoxazole (50.1%) and 331 with fluoroquinolones (49.9%). Three cohort studies were designed to compare the effect of the two drugs, whereas the others had other purposes. Levofloxacin was most frequently used among fluoroquinolones (187/331, 56.5%), followed by ciprofloxacin (114/331, 34.4%). The overall mortality rate was 29.6%. Using pooled ORs for the mortality of each study, fluoroquinolone treatment (OR 0.62, 95% CI 0.39–0.99) was associated with survival benefit over trimethoprim-sulfamethoxazole treatment, with low heterogeneity (I2 = 18%). Specific fluoroquinolones such as ciprofloxacin (OR 0.44, 95% CI 0.17–1.12) and levofloxacin (OR 0.78, 95% CI 0.48–1.26) did not show a significant difference in comparison with trimethoprim-sulfamethoxazole. In the sub-group analyses of adult and bacteraemic patients, significant differences in mortality were not observed between fluoroquinolones and trimethoprim-sulfamethoxazole.ConclusionsBased on a meta-analysis of non-randomized studies, fluoroquinolones demonstrated comparable effects on mortality of S. maltophilia infection to trimethoprim-sulfamethoxazole, supporting the use of fluoroquinolones in clinical S. maltophilia infections. Although the pooled analysis of overall studies favoured fluoroquinolones over trimethoprim-sulfamethoxazole, the studies included were observational, and sub-group analyses of certain fluoroquinolone agents did not show statistical differences with trimethoprim-sulfamethoxazole. Randomized clinical studies are needed to address these issues.  相似文献   
36.
HLA haplotype mismatches have been associated with an elevated risk of acute graft-versus-host disease (aGVHD) in patients undergoing HLA-matched unrelated donor (URD) hematopoietic cell transplantation (HCT). The gamma block (GB) is located in the central MHC region between beta and delta blocks (encoding HLA-B and -C and HLA-DQ and -DR antigens, respectively) and contains numerous inflammatory and immune regulatory genes, including Bf, C2, and C4 genes. A single-center study showed that mismatches in SNPs c.2918+98G, c.3316C, and c.4385C in the GB block (C4 SNPs) were associated with higher risk of grade III-IV aGVHD. We investigated the association of GB SNP (GBS) mismatches with outcomes after 10/10 and 9/10 URD HCT (n?=?714). The primary outcome was acute GVHD. Overall survival, disease-free survival, transplantation-related mortality, relapse, chronic GVHD, and engraftment were also analyzed. DNA samples were GBS genotyped by identifying 338 SNPs across 20 kb using the Illumina NGS platform. The overall 100-day incidence of aGVHD grade II-IV and II-IV were 41% and 17%, respectively. The overall incidence of matching at all GBSs tested and at the C4 SNPs were 23% and 81%, respectively. Neither being matched across all GB SNPs tested (versus mismatched) nor having a higher number of GBS mismatches was associated with transplantation outcomes. There was no association between C4 SNP mismatches and outcomes except for an unexpected significant association between having 2 C4 SNP mismatches and a higher hazard ratio (HR) for relapse (association seen in 15 patients only; HR, 3.38, 95% confidence interval, 1.75 to 6.53; P?=?.0003). These data do not support the hypothesis that mismatching at GB is associated with outcomes after HCT.  相似文献   
37.
The revised International Staging System (R-ISS) combines ISS with genetic markers and lactate dehydrogenase and can prognosticate newly diagnosed multiple myeloma (MM). Early relapse (<24 months) after upfront autologous hematopoietic cell transplantation (AHCT) strongly predicts inferior overall survival (OS). We examined the ability of R-ISS in predicting early relapse and its independent prognostic effect on postrelapse survival after an early relapse. Using the Center for International Blood and Marrow Transplant Research database we identified MM patients receiving first AHCT within 18 months after diagnosis with available R-ISS stage at diagnosis (n?=?628). Relative risks of relapse/progression, progression-free survival (PFS), and OS were calculated with the R-ISS group as a predictor in multivariate analysis. Among early relapsers, postrelapse survival was tested to identify factors affecting postrelapse OS. The cumulative incidence of early relapse was 23%, 39%, and 50% for R-ISS I, R-ISS II, and R-ISS III, respectively (P < .001). Shorter PFS and OS were seen with higher stage R-ISS. R-ISS was independently predictive for inferior postrelapse OS among early relapsers, as was the presence of ≥3 comorbidities and the use of ≥2 induction chemotherapy lines. R-ISS stage at diagnosis predicts early post-AHCT relapse and independently affects postrelapse survival among early relapsers.  相似文献   
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39.
Severe forms of osteogenesis imperfecta (OI) are usually caused by mutations in genes that code for collagen Type I and frequently are associated with craniofacial abnormalities. However, the dental and craniofacial characteristics of OI caused by the p.Ser40Leu mutation in the IFITM5 gene have not been reported. We investigated a 15‐year‐old girl with severe OI caused by this mutation. She had marked deformations of extremity long bones. There were no clinical or radiological signs of dentinogenesis imperfecta, but one tooth was missing and several teeth were impacted. Cone beam computed tomography revealed a generalized osteopenic appearance of the craniofacial skeleton, bilateral enlargement of mandibular bodies, and areas of cortical erosions. The cranial base and skull showed a generalized granular bone pattern with a mixture of osteosclerosis and osteolysis. Sphenoid and frontal sinuses were congenitally missing. Cephalometric analysis indicated a Class III growth pattern. In this case, the IFITM5 p.Ser40Leu mutation did not affect tooth structure but was associated with deformities in craniofacial bones that resemble those in the other parts of the skeleton.  相似文献   
40.
The objective of this study was to characterize the oncogenic actions of a recently identified cancer-associated gene YWHAZ (also named as 14-3-3 ζ/δ) in urothelial carcinomas of the urinary bladder (UCUB). A genome-wide study revealed YWHAZ to be involved in the amplicon at 8q22.3, and its genetic amplification was detected predominantly in muscle-invasive bladder cancer (MIBC). Immunohistochemical staining confirmed the association of YWHAZ overexpression with higher tumor stages, lymph node/vascular invasion, and mitotic activity. Univariate and multivariate analyses further indicated the prognostic potential of YWHAZ for more aggressive cancer types. Both gene set enrichment analysis and STRING network studies suggested involvement of YWHAZ in regulating caspase-mediated apoptosis. Ectopic expression of YWHAZ in bladder cells with low endogenous YWHAZ levels boosted cell resistance to doxorubicin and cisplatin, as well as to ionizing radiation. Conversely, YWHAZ-knockdown using specific shRNA in cells with high endogenous YWHAZ levels diminished survival activity, suppressing cell growth and increasing cell death. Our findings confirm the essential role played by YWHAZ in sustaining cell proliferation during chemo/radiotherapy. Treatments based on anti-YWHAZ strategies may thus be beneficial for UCUB patients overexpressing YWHAZ. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   
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