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21.
Fabry disease is secondary to deficiency of the lysosomal enzyme α-galactosidase A, leading to altered glycosphingolipid metabolism and accumulation that is often associated with endothelial dysfunction. Current evidence suggests that there is impairment of the vascular nitric oxide pathway, with abnormalities evident in the cerebral circulation and in the dermal vasculature of patients with Fabry disease. Some of these findings have been confirmed in a mouse model of Fabry disease. The murine model, however, allows investigation of Fabry disease at a non-clinical level and a near complete investigation of biological processes within an affected tissue. This is of particular utility in allowing gene expression analysis of clinically inaccessible tissues such as the aorta.
Conclusion: Future developments in array technology for proteins and DNA single nucleotide polymorphism analysis, together with gene expression microarray analysis, may open a new chapter in our understanding of the biology of lysosomal storage disorders.  相似文献   
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BackgroundPatients with KRAS-mutant cancers have limited treatment options. Here we present a phase I study of JNJ-74699157, an oral, selective, covalent inhibitor of the KRAS G12C isoform, in patients with advanced cancer harboring the KRAS G12C mutation.MethodsEligible patients (aged ≥18 years) who had previously received or were ineligible for standard treatment received JNJ-74699157 once daily on a 21-day cycle. Dose escalation was guided by a modified continual reassessment method.ResultsTen patients (100 mg: 9 and 200 mg: 1) were enrolled. Tumor types included non–small cell lung cancer (n = 5), colorectal cancer (n = 4), and carcinoma of unknown primary site (n = 1). The median age was 65 (range: 36-74) years and median treatment duration was 2.91 (range: 0.5-7.5) months. Dose-limiting toxicities of grades 3–4 increased blood creatinine phosphokinase (CPK) were observed in 100 mg and 200 mg dose levels. The most common adverse event was increased blood CPK (6 patients). No significant clinical benefit was observed; the best response was stable disease in 4 patients (40%).ConclusionBased on dose-limiting skeletal muscle toxicities and the lack of efficacy at the 100 mg dose, further enrollment was stopped. The safety profile of JNJ-74699157 was not considered favorable for further clinical development.ClinicalTrials.gov IdentifierNCT04006301  相似文献   
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BackgroundIn metastatic pancreatic adenocarcinoma, few data are available on the use of granulocyte-colony stimulating factor (G-CSF) prophylaxis and its impact on dose-intensity (DI), or the link between DI and progression-free survival (PFS). This study assessed the impact of G-CSF prophylaxis on the DI received by patients and the relationship between full DI and PFS according to chemotherapy regimens.Patients and MethodsPatients from three first-line randomized phase II clinical trials were included in this retrospective cohort. G-CSF prophylaxis groups were identified and balanced according to baseline characteristics using a propensity score. Patients were classified into 2 treatment groups (FOLFIRINOX vs FOLFIRI/nab-paclitaxel (NAB)). DI was a binary variable (full/reduced). Adverse events were defined using NCI-CTCAE v4.0.ResultsOf the 498 patients, 154 (31%) were in “prophylaxis” group; 179 (36%) were treated by FOLFIRINOX and 319 (64%) by FOLFIRI/NAB. In FOLFIRINOX group, G-CSF prophylaxis was significantly associated with a higher rate of full DI (OR, 5.07; 95% CI, 1.52-16.90; P < .01) while in FOLFIRI/NAB group, it was significantly associated with a lower rate of full DI (OR, 0.23; 95% CI, 0.06-0.83; P = .03). Full DI was associated with a non-significant increase in PFS (FOLFIRINOX group: HR 0.83; 95% CI, 0.59-1.16; P = .27; FOLFIRI/NAB group: HR 0.84; 95% CI, 0.63-1.11; P = .22).ConclusionGranulocyte-colony stimulating factor prophylaxis was associated with a higher rate of full DI with FOLFIRINOX. Full DI was associated with a non-significant increase in PFS. These results need to be confirmed prospectively.  相似文献   
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Objectives Film coatings based on blends of Eurylon 6 HP‐PG (a hydroxypropylated and pregelatinized high amylose starch) and ethylcellulose were to be evaluated as promising coating materials for site‐specific drug delivery to the colon of patients suffering from inflammatory bowel diseases. Methods Pellet starter cores containing 60% 5‐aminosalicylic acid were prepared by extrusion/spheronization and coated with different Eurylon 6 HP‐PG : ethylcellulose blends at various coating levels. Drug release was measured in media simulating the contents of the upper gastrointestinal tract (in the presence and absence of enzymes) as well as in media simulating the contents of the colon. Key findings 5‐Aminosalicylic acid release could effectively be suppressed in 0.1 N HCl and phosphate buffer pH 6.8, optionally containing pepsin or pancreatin, but occurred as soon as the pellets came into contact with culture medium inoculated with faecal samples from inflammatory bowel disease patients. This can be attributed to the partial degradation of the starch derivative by enzymes secreted by bacteria present in the colon of these patients. Conclusions The presented drug delivery system is adapted to the pathophysiological conditions in inflammatory bowel disease patients. Furthermore, drug release remained unaltered upon 1 year open storage.  相似文献   
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Neonatal and 5-year outcomes after birth at 30-34 weeks of gestation   总被引:1,自引:0,他引:1  
OBJECTIVE: To evaluate the rates of in-hospital death, neonatal complications, and 5-year outcomes of infants born at 30-34 weeks of gestation. METHODS: In nine regions of France, all 2,020 stillbirths and live births at 30, 31, and 32 weeks in 1997 and all 457 births at 33 and 34 weeks in April and October 1997 were recorded. Survivors were evaluated at 5 years of age. RESULTS: Increasing gestational age from 30 to 34 weeks was associated with progressive decreases in in-hospital mortality (from 8.1% to 0.4%) and neonatal complications (respiratory distress syndrome, 43.8% to 2.6%; maternofetal infections, 7.2% to 2.6%; and severe white matter injury, 5.5% to 1.3%). Although infants at 33 and 34 weeks of gestation rarely experienced necrotizing enterocolitis, bronchopulmonary dysplasia, or nosocomial infections, they still required endotracheal ventilation, antibiotics, or parenteral nutrition. At 5 years of age, older gestational age was associated with significant decreases in rates of cerebral palsy (6.3% at 30 weeks and 0.7% at 34 weeks) and mild to severe cognitive impairments (35.3% at 30 weeks and 23.9% at 34 weeks). In singletons, preterm rupture of membranes or preterm labor carried an increased risk of cerebral palsy but not of cognitive impairment. CONCLUSION: Neonates born at 30-34 weeks experienced substantial morbidity and often required admission to neonatal intensive care units. These outcomes suggest that prolonging pregnancies beyond 34 weeks may be desirable whenever possible. Infants born at 30-34 weeks should be carefully monitored to ensure prompt detection and management of neurodevelopmental impairment.  相似文献   
28.
The vaccinia virus (VACV) was previously used as a vaccine for smallpox eradication. Nowadays, recombinant VACVs are developed as vaccine platforms for infectious disease prevention and cancer treatment. The conventional method for genome editing of the VACV is based on homologous recombination, which is poorly efficient. Recently, the use of CRISPR/Cas9 technology was shown to greatly improve the speed and efficiency of the production of recombinant VACV expressing a heterologous gene. However, the ability to rapidly recover viruses bearing single nucleotide substitutions is still challenging. Notwithstanding, ongoing studies on the VACV and its interaction with the host cell could benefit from viral gene targeted mutagenesis. Here, we present a modified version of the CRISPR/Cas9 system for the rapid selection of mutant VACV carrying point mutations. For this purpose, we introduced a silent mutation into the donor gene (which will replace the wildtype gene) that serves a double function: it is located in the PAM (NGG) sequence, which is essential for Cas9 cleavage, and it alters a restriction site. This silent mutation, once introduced into the VACV genome, allows for rapid selection and screening of mutant viruses carrying a mutation of interest in the targeted gene. As a proof of concept, we produced several recombinant VACVs, with mutations in the E9L gene, upon which, phenotypic analysis was performed.  相似文献   
29.
Waldenström macroglobulinemia is a rare chronic lymphoproliferative disorder. Treatments are currently reserved for symptomatic patients and usually consist of nucleoside analogues (NAs), alkylating agents, bortezomib, and monoclonal antibodies, alone or in combination. Fludarabine and 2-chlorodeoxyadenosine (2-CdA) have been studied in first-line treatment of Waldenström macroglobulinemia (WM) since the end of the 1990s. In monotherapy, response rates vary between 36% and 94%. In a phase III trial, fludarabine in monotherapy was more efficient than chlorambucil for progression-free survival (PFS) (37.8 vs. 27.1 months), duration of response (DOR) (38.5 vs. 21.3 months) and overall survival (OS) (median not reached vs. 69.8 months), but the overall response rate (ORR) was similar (45.6% and 35.9%). NAs have been studied in combination with rituximab and/or alkylating agents for increasing the quality and duration of the response. Hematologic toxicities are a major concern, limiting the indication for NAs in first-line treatment to patients who are not candidates for autologous stem cell transplantation, those in need of rapid control of the disease, or those with poor prognostic factors.  相似文献   
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