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1.

Background

Treatment of advanced anal squamous cell cancer (SCC) is usually with the combination of cisplatin and 5-fluorouracil, which is associated with heterogeneous responses across patients and significant toxicity. We examined the safety and efficacy of a modified schedule, FOLFCIS (leucovorin, fluorouracil, and cisplatin), and performed an integrated clinical and genomic analysis of anal SCC.

Patients and Methods

We reviewed all patients with advanced anal SCC receiving first-line FOLFCIS chemotherapy – essentially a FOLFOX (leucovorin, fluorouracil, and oxaliplatin) schedule with cisplatin substituted for oxaliplatin – in our institution between 2007 and 2017, and performed deep sequencing to identify genomic markers of response and key genomic drivers.

Results

Fifty-three patients with advanced anal SCC (48 metastatic; 5 unresectable, locally advanced) received first-line FOLFCIS during this period; all were platinum-naive. The response rate was 48% (95% confidence interval [CI], 32.6%-63%). With a median follow-up of 41.6 months, progression-free survival and overall survival were 7.1 months (95% CI, 4.4-8.6 months) and 22.1 months (95% CI, 16.9-28.1 months), respectively. Among all patients with advanced anal SCC that underwent sequencing during the study period, the most frequent genomic alterations consisted of chromosome 3q amplification (51%) and mutations in PIK3CA (29%) and KMT2D (22%). No genomic alteration correlated with response to platinum-containing treatment. Although there were few cases, patients with human papillomavirus-negative anal SCC did not appear to benefit from FOLFCIS, and all harbored distinct genomic profiles with TP53, TERT promoter, and CDKN2A mutations.

Conclusions

FOLFCIS appears effective and safe as first-line chemotherapy in patients with advanced anal SCC and represents an alternative treatment option for these patients.  相似文献   
2.
BACKGROUND: Lung infection with Burkholderia cepacia complex before lung transplantation in patients with cystic fibrosis is a major risk factor for decreased post-operative survival rates compared with those of patients colonized with the more common opportunistic pathogen Pseudomonas aeruginosa. Because adherence to mucosal surfaces is an important initial step in infection, we investigated the use of non-toxic neutral polysaccharides and a sugar alcohol to prevent adherence of B cepacia complex to allograft airway epithelium. METHODS: We used human airway explants prepared from donor tracheobronchial tissue to test the effect of dextrans and xylitol in inhibiting the binding of Burkholderia cepacia complex. We used immunofluorescence and electron microscopy to determine the distribution of bacteria in the explants. RESULTS: Burkholderia cepacia complex bound to the explants and was found only in the surface mucus layer. Dextran 40 kd applied before adding the bacteria decreased the number of bound organisms by 80% to 99%. Smaller molecular mass dextrans (4 and 20 kd) were ineffective. Xylitol inhibited bacterial binding by 67% to 85%. Both agents seemed to decrease the thickness of the surface mucus, suggesting that they may indirectly inhibit bacterial binding by removing adherent surface mucus. CONCLUSIONS: Treating donor lungs with dextran 40 kd or xylitol before (and possibly after) surgery may inhibit the adherence of Burkholderia cepacia complex to airways and may prevent or decrease subsequent infection of the allografts.  相似文献   
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While current donor selection with clinical findings is generally effective, the imprecise nature of the assessment forces clinicians to remain on the conservative side. A reliable biological marker would assist donor selection and would improve donor organ utilization. We collected biopsies from 169 donor lungs before implantation. Expression levels of IL-6, IL-8, IL-10, TNF-alpha, IFN-gamma and IL-1beta were measured by quantitative real-time RT-PCR (qRT-PCR). Seventeen cases died within 30 days after transplantation. No donor factor was significantly associated with 30-day mortality. Univariate analysis of the 84 cases for development of the prediction model showed that IL-6, IL-8, TNF-alpha and IL-1beta were risk factors for mortality and IL-10 and IFN-gamma were protective factors. We analyzed the cytokine expression ratios of risk to protective cytokines. A stepwise logistic regression for 30-day mortality demonstrated that a model containing the ratio of IL-6/IL-10 was the most predictive (p = 0.0013). When applied to the remaining 85 cases for validation, the test of model fit was significant (p = 0.039). Using the cytokine ratio, we were able to define three risk groups with striking differences in survival (p = 0.0003). Multi-cytokine analysis of the donor lung graft with qRT-PCR shows significant promise as a strategy to biologically evaluate the donor lung prior to implantation.  相似文献   
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Meetings     
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6.
BACKGROUND: The presence of the three forms of IgE receptor - the heterotrimeric high-affinity receptor for IgE (Fc(epsilon)RI), the low-affinity receptor for IgE (Fc(epsilon)RII/CD23) and the Mac-2/IgE-binding protein (epsilonBP) - has been demonstrated on human neutrophils. We have previously shown that specific allergens are able to activate functional responses by neutrophils from allergic patients sensitized to those allergens. Neutrophils are present at the sites of allergic inflammation. The primary (azurophilic) granules of neutrophils contain a variety of enzymes, such as elastase, that might potentiate inflammation. It is not known whether specific allergens are able to elicit elastase release by neutrophils from allergic patients. In addition, we attempted to evaluate the relationship between neutrophil degranulation and lung function of the patients, measured as FEV(1). METHODS: Neutrophils were challenged in vitro with the specific allergens that produced clinical symptoms in asthmatic patients. The cells were also challenged with allergen to which the patients were not sensitive. Neutrophils from normal subjects were challenged with allergens as control. RESULTS: The in vitro challenge of neutrophils with allergens to which the patients were sensitive elicited a release of elastase by these cells. The in vitro activation of neutrophils was highly allergen specific; allergens other than those accounting for clinical symptoms did not evoke elastase release, and allergens were ineffective on neutrophils from healthy donors. A significant inverse correlation was observed between elastase release and patients' lung function, measured as FEV(1). CONCLUSION: An IgE-dependent mechanism might promote elastase release by neutrophils at allergic sites. There is a significant inverse relationship between levels of elastase released by neutrophils from allergic patients and lung function, as assessed by FEV(1).  相似文献   
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We present the case of a 24 year-old patient that developed massive hemolysis shortly after percutaneous left ventricular assist device, Impella 2.5, was placed. The hemolysis occurred without device alarm while the device was in the correct position. Further investigation of the device revealed fiber wrapped around the tip of the device, as a culprit. This case emphasizes on the special caution applied during device preparation to minimize the possible adverse events.  相似文献   
9.
Periodontal disease is one of the most common conditions affecting humans, and current treatment strategies, which focus on the removal and long‐term control of dental plaque, are generally successful in eliminating active disease and promoting tissue repair. However, regeneration of the supporting structures of the tooth remains an elusive goal and a challenge. The formation of new bone and cementum with supportive periodontal ligament is the ultimate objective, but current regeneration therapies are incapable of achieving this in a predictable way. The regeneration of periodontal tissue requires a combination of fundamental events, such as appropriate level and sequencing of regulatory signals, the presence of progenitor cells, an extracellular matrix or carrier and an adequate blood supply. Based on tissue‐engineering concepts, the regeneration process may be modulated by manipulating the signaling pathways of regulatory molecules, the extracellular matrix or scaffold, or the cellular components. The identification of mesenchymal stem cells from bone marrow started a new era in regenerative medicine. Tissue engineering using mesenchymal stem cells became a therapeutic option with several advantages, including high‐quality regeneration of damaged tissues without the formation of fibrous tissue, minimal donor‐site morbidity compared with autografts and a low risk of autoimmune rejection and disease transmission. The aim of this review was to describe the main sources of mesenchymal stem cells from tissues in the oral cavity and the potential of these cells in regenerative therapy. Special attention is paid to gingival tissue‐derived mesenchymal stem cells because they represent the most accessible source of stem cells in the human mouth.  相似文献   
10.
Donor‐specific anti‐HLA antibodies (DSA) causing CAMR are responsible for a high proportion of long‐term graft failures after RTX. We studied the prevalence of DSA in RTX children biopsied for creeping Cr, its relationship with NA, and patient and graft survival according to histopathology. Between 2008 and 2013, 92 children were biopsied at a median of 38 months post‐RTX. At biopsy, the prevalence of DSA was 49% and C4d 70%. NA rate was 45%, higher in adolescents (60%). Most frequent diagnoses were CAMR (72%) and interstitial fibrosis with tubular atrophy (IFTA) (28%). Forty‐five of 66 patients with CAMR (68%) had detectable DSA. Twenty‐one DSA‐negative patients with CAMR had histological damage (IFTA + C4d positivity). C4d was detected in 64 of 66 biopsies with CAMR. Recipients with IFTA alone had neither C4d, nor detectable DSA, and were adherent. Graft survival at five yr was 89% in patients with CAMR, 79% in those with CAMR + TCMR Banff I, 33% in those with CAMR + TCMR Banff II, and 96% in those with IFTA. ABMR and complement activation were frequent in children biopsied for creeping Cr. Recipients with DSA were more likely to be non‐adherent and have CAMR or CAMR + TCMR and worse graft survival.  相似文献   
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