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91.
BACKGROUNDNeuroendocrine gastrointestinal tumors (NETs) are rare and have different natural behaviors. Surgery is the gold standard treatment for local disease while radiotherapy has been demonstrated to be ineffective. Poorly differentiated neuroendocrine carcinomas (NECs) represent only 5%-10% of digestive NETS. Due to aggressive growth and rapid metastatic diffusion, early diagnosis and a multidisciplinary approach are mandatory. The role of surgery and radiotherapy in this setting is still debated, and chemotherapy remains the treatment of choice.CASE SUMMARYA 42-year-old male with an ulcerated bleeding rectal lesion was diagnosed with a NEC G3 (Ki67 index > 90%) on May 2015 and initially treated with 3 cycles of first-line chemotherapy, but showed early local progressive disease at 3 mo and underwent sphincter-sparing open anterior low rectal resection. In September 2015, the first post-surgery total-body computed tomography (CT) scan showed an early pelvic disease relapse. Therefore, systemic chemotherapy with FOLFIRI was started and the patient obtained only a partial response. This was followed by pelvic radiotherapy (50 Gy). On April 2016, a CT scan and 18F-fluorodeoxyglucose positron emission tomography imaging showed a complete response (CR) of the pelvic lesion, but pathological abdominal inter-aortocaval lymph nodes were observed. Due to disease progression of abdominal malignant nodes, the patient received radiotherapy at 45 Gy, and finally obtained a CR. As of January 2021, the patient has no symptoms of relapse and no late toxicity after chemotherapy or radiotherapy.CONCLUSIONThis case demonstrates how a multimodal approach can be successful in obtaining long-term CR in metastatic sites in patients with high grade digestive NECs.  相似文献   
92.
BACKGROUND: An increasing number of apheresis machines are becoming available for peripheral blood progenitor cell (PBPC) collection in children. STUDY DESIGN AND METHODS: At the Children's Hospital of Florence (Italy), three apheresis machines were evaluated: MCS 3P (Haemonetics) (10 procedures in 4 patients, aged 10–12 years, weight 23.5-64 kg), Spectra, (COBE) (8 procedures in 3 patients, aged 4–17 years, weight 19–59 kg), and AS104 (Fresenius) (24 procedures in 9 patients, aged 2–16 years, weight 13.6-60 kg). For PBPC quantitative analysis, CD34 cytofluorimetry was employed. Relevant variables analyzed included efficiency of CD34+ cell extraction and enrichment, mononuclear cell purity and red cell contamination of the apheresis components, and platelet count decreases after leukapheresis. RESULTS: No significant differences in CD34+ cell-extraction abilities were found. However, the AS104 provided consistently purer leukapheresis components in terms of mononuclear cell and CD34+ cell enrichment (441 +/− 59%, vs. 240 +/− 35% and 290 +/− 42% for MCS 3P and Spectra, respectively). Postapheresis platelet counts dropped the least with the AS104. The smallest patient who underwent apheresis with MCS 3P (the only machine working on discontinuous flow and hence with greater volume shifts) weighed 23.5 kg and tolerated the procedure well, with no signs of hemodynamic instability. No significant complications were observed. CONCLUSION: All machines seem to have comparable PBPC extraction efficiency, but the AS104 seems to give the component with the greatest PBPC enrichment. This feature might be relevant for further ex vivo cell processing (CD34+ cell selection, expansion, and so on).  相似文献   
93.
This study was undertaken to clarify the mechanisms by which C-fiber degeneration at neonatal stages exacerbates the inflammatory responses of rat airways. Rats were treated with capsaicin at neonatal stages and immunized with ovalbumin (OVA) at adult ages. Challenge of capsaicin-pretreated rats with OVA promoted a higher influx of neutrophils in bronchoalveolar lavage (BAL) fluid compared with the vehicle group. No significant differences were found for the other cell types. The increased adhesion of N-formyl-methionyl-leucyl-phenylalanine (fMLP; 0.1 microM)- and phorbol myristate acetate (PMA; 1 microM)-treated neutrophils to fibronectin-coated wells did not differ among vehicle- and capsaicin-pretreated rats. Additionally, fMLP (10 microM), platelet-activating factor (0.1 microM), and substance P (50 microM) induced a significant neutrophil chemotaxis, but no differences were found among vehicle and capsaicin groups. Increased levels of tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-10, and leukotriene B4 in BAL fluid as well as higher expression of cytokine-induced neutrophil chemoattractant (CINC)-3 in lung homogenates were detected in the capsaicin group compared with vehicle group. In the capsaicin group, chronic treatment with compound 48/80 restored the TNF-alpha levels to control values and prevented the neutrophil influx in BAL fluid. The enhanced production of TNF-alpha, superoxide anion, and nitrite by isolated alveolar macrophages in response to lipopolysaccharide (3 microg/ml), PMA (10 nM), and/or zymosan (100 particles/cell) did not differ between vehicle- and capsaicin-pretreated rats. In conclusion, chronic neuropeptide depletion promoted by neonatal capsaicin treatment up-regulates airways mast cells, which upon activation by antigen at adult ages, release large amounts of cytokines such as TNF-alpha and CINC-3 that accounts for the massive airways neutrophil infiltration.  相似文献   
94.
The clinical significance of Aspergillus fungaemia in the setting of a deep-seated aspergillosis has not been clearly established. Among 107 microbiologically documented Aspergillus infections in patients with haematological diseases observed over a 17-year period, blood cultures grew Aspergillus species from 10 cases. Aspergillus fungaemia was documented in 9 out of 89 (10.1%) patients with pulmonary aspergillosis at a median of 5 d from the onset of clinical signs of infection, and in one patient with central venous catheter focal infection. Five (50%) patients died as a result of fungal infection a median of 12 d (range 4--48) from the documentation of Aspergillus fungaemia. A comparison between cases of invasive aspergillosis with or without fungaemia showed that fungaemic patients were similar to those without positive blood cultures regarding clinical presentation, risk factors, clinical course and outcome. The diagnostic role of Aspergillus fungaemia in the setting of a deep-seated infection is limited because blood cultures become positive when a microbiological or clinical diagnosis of aspergillosis has already been performed. Aspergillus fungaemia does not necessarily seem to be correlated with a disseminated infection or a poorer prognosis.  相似文献   
95.
96.
Purpose. We report a case of woman with Marfan syndrome and longstanding postlensectomy scleral wound dehiscence. Methods. A 34-year-old woman with Marfan syndrome who underwent lensectomy 20 years ago had conjunctival leakage with chronic hypotony and conjunctival cystic degeneration secondary to scleral wound dehiscence. Presentation, clinical evaluation, and particular treatment with autologous cultivated conjunctival epithelium transplantation and scleral patch graft are described. Results. A 6-month follow-up confirmed complete epithelization of the ocular surface and absence of leaking from the wound with normal intraocular pressure. Conclusions. Transplantation of autologous cultivated conjunctival epithelium appears to be a valid strategy in the treatment of ocular disease requiring extensive excision of the conjunctiva.  相似文献   
97.
The atypical HUS (aHUS) is a rare genetic disease, with poor prognosis, characterized by microangiopathic hemolytic anemia, thrombocytopenia and acute renal failure. This syndrome is often related to mutations in the genes encoding complement regulatory proteins. A 26-year-old woman with homozygous mutation in complement factor H (CFH) developed a relapse of aHUS at 17th week of pregnancy. Despite treatment with plasma exchange (PEX), at the 26th week of gestation eculizumab was started. The sequential treatment with eculizumab after PEX was well tolerated and it has led to clinical remission.  相似文献   
98.
Abstract: Very few data are available on the comparison of infectious complications in peripheral blood stem cell transplantation (PBSCT) and bone marrow transplant (BMT). The objective of this study was to evaluate the severity and frequency of infectious complications in patients randomized to receive PBSCT or BMT. We retrospectively reviewed the charts of all patients included in a randomized clinical trial comparing PBSCT (27 patients) and BMT (29 patients). We analyzed two periods: pre‐engraftment and post‐engraftment. In the pre‐engraftment period, we compared the two groups with respect to the duration of neutropenia, antibiotic use and hospitalization, and documentation of infection. In the post‐engraftment period, we analyzed the occurrence and severity of graft‐versus‐host disease (GVHD), duration of cyclosporine, corticosteroids, antibiotic, antiviral and antifungal prophylaxis, number of episodes of infection, and death rates. Patients receiving PBSCT had shorter duration of neutropenia, but there were no differences in the incidence of infections or duration of antibiotic therapy. Patients receiving PBSCT had a higher incidence of extensive chronic GVHD (65% vs. 39%, P=0.08), longer duration of cyclosporine use (risk ratio [RR] 1.97), corticosteroids (RR 1.66), antibacterial (RR 2.60), antifungal (RR 2.50), anti‐Pneumocystis carinii (RR 2.06) and anti‐cytomegalovirus (RR 1.44) prophylaxis, and more infectious episodes (3.65 vs. 2.32 per 1000 days at risk, RR 1.57). There were no differences in death rates. Multivariate analysis identified the use of steroids as the most significant variable associated with infectious episodes. PBSCT was associated with more infections in the post‐engraftment period.  相似文献   
99.
Recombinant human (rh) interleukin-3 (IL-3) stimulated the proliferation and differentiation of erythroid, granulocyte, macrophage, eosinophil (Eo), and mixed colonies as well as megakaryocytes from human bone marrow cells. rh IL-3 was a weaker stimulus than rh granulocyte-macrophage colony-stimulating factor (GM- CSF) for day 14 myeloid cell colonies. At day 7 of incubation, rh IL-3 stimulated a few G, M, and Eo clusters but no colonies. This loss of responsiveness of myeloid cells to rh IL-3 was accentuated with further differentiation of the cells. rh IL-3 stimulated very few or no clones after five-day incubation with enriched promyelocytes and myelocytes, whereas rh GM-CSF was an efficient stimulus. Responsiveness to rh IL-3 was completely lost in postmitotic mature neutrophils. Incubation of these cells with rh IL-3 did not result in enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) of tumor cells or superoxide anion production after stimulation with formyl-methyl-leucyl-phenylalanine (FMLP), although they could be stimulated by rh GM-CSF. In addition, preincubation of neutrophils with different concentrations of rh IL-3 failed to increase or decrease their response to rh GM-CSF. In contrast to neutrophils, mature Eos could be stimulated by rh IL-3 to kill antibody-coated tumor cells. These results show that cells of the neutrophilic myeloid series lose their responsiveness to h IL-3 as they differentiate and suggest that although h IL-3 may be an important therapeutic agent to use for hematopoietic regeneration in vivo, the lack of stimulation of mature neutrophil function makes it an unlikely sole candidate as adjunct therapy for treatment of infectious diseases.  相似文献   
100.
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