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41.
Neurosurgical Review - Capillary hemangiomas (CHs) of the central nervous system represent a rare diagnosed pathology. CHs are benign vascular tumors whose most common manifestations are dermal and...  相似文献   
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Summary Intraperitoneal (i.p.) 5-fluoro-2-deoxyuridine (Floxuridine, FUdR, FdUrd) was evaluated in a phase I study at a starting level of 500 mg given on 1 day in 2 I 1.5% dialysate. Escalations within patients were allowed every other cycle. A total of 23 patients (age, 32–78 years) received 108 treatment courses. Local tolerance at all dose levels was excellent, with no cases of drug-related peritonitis being observed. Nausea and vomiting increased in severity in relation to dose and was universal at >3,000 mg ×3 days. One patient each developed grade 1 mucositis as well as diarrhea at a dose of 3,000 mg×3 days and leukopenia and thrombocytopenia at 5,000 mg×3 days. Peritoneal fluid (PF) and plasma (PL) FdUrd profiles were monitored by an HPLC method in 13 subjects, with 7 being studied serially at 2–4 increment doses for up to 6 h. Profiles that exhibited apparent linear pharmacokinetics gave PF drug levels 2–4 logs higher than the PL counterparts, with the latter essentially declining in parallel to the former, indicating that the disposition of FdUrd from the peritoneal compartment is rate-determining. The mean terminal half-life for PF FdUrd was found to be 115 min and mean peritoneal clearance was 25 ml/min. The vast differences in drug levels and AUC found between the PF and the PL profiles suggests a high systemic clearance of FdUrd, which was confirmed in two patients receiving 2 g FdUrd by short i.v. infusion. A disproportionate increase in the plasma FdUrd levels and the corresponding AUC values was found with increasing dose, suggesting a disproportionate increase in the systemic partitioning of FdUrd when doses were escalated within a patient. Substantial levels of peritoneal 5-fluorouracil (FUra) were also detected in most of the subjects. Thus, FdUrd was found to have several desirable properties for i.p. administration: (1) a 2- to 4-log pharmacologic advantage, (2) the absence of local toxicities, and (3) a favorable antitumor spectrum and some evidence of antitumor effects in this phase I and pharmacology study. A 3,000-mg dose given in 2 l 1.5% dialysate for 3 consecutive days exhibited antitumor activity and produced no systemic toxicity except nausea and vomiting, which was controlled by antiemetics. This dose schedule is therefore recommended for phase II trials directed against small-volume disease in the peritoneal cavity, such as may be found in some stages of ovarian and gastrointestinal cancers. In addition, it is suitable for further exploration as a part of regimens including systemic therapy or drugs that modulate the action of fluoropyrimidines.Supported in part by Cancer Center Core Grant CA 14089, by ROI CA 50 412, by an ACS Institutional Grant (IN21Z, to C. R.) and by the Italian-American Foundation award (to N. C.)Deceased  相似文献   
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An improved characterization of the dynamics of postural sway can provide a better understanding about the functional organization of the postural control system as well as a more robust tool for postural pattern recognition. To this aim, a novel parameterization was applied to the stabilogram diffusion analysis formerly proposed by Collins and De Luca [Collins JJ, De Luca CJ. Open-loop and closed-loop control of posture: a random-walk analysis of center-of-pressure trajectories. Exp Brain Res 1993;95:308–18] that considered the act of maintaining posture as a stochastic process. The main purpose of the present technique was to overcome some drawbacks of the model presented by Collins and De Luca that may restrain its potential application in clinical practice. The approach uses a unique non-linear model to describe the center of pressure (COP) dynamics that reduces the number of parameters and decreases their intra-subject variability; consequently, fewer trials are required to perform reliable estimates of stochastic parameters and this is of particular importance for subjects that cannot afford many repeated measurements because of age or pathology. Four new statistical mechanics parameters (NSMP) were computed on the log–log stabilogram diffusion plots and their estimates were compared in terms of reliability and sensitivity to the visual conditions with: (1) a minimal set of four summary statistic scores (SSS); and (2) the six statistical mechanics parameters (SMP) proposed by Collins and De Luca. All four NSMP showed at least a fair-to-good reliability (intraclass correlation coefficient, ICC>0.49) while SMP (ICC>0.20) showed some poor reliability. A better overall reliability was also observed with respect to SSS. Moreover, only NSMP had a similar score for eyes open and eyes closed conditions. Three out of four NSMP were also significantly sensitive to eyes open or closed conditions (P<0.001) while only three out of six SMP were sensitive to operating conditions (P<0.01).  相似文献   
45.
PURPOSE: Point mutations within the ABL kinase domain of the BCR-ABL gene have been associated with clinical resistance to imatinib mesylate in chronic myeloid leukemia (CML) patients. To shed further light on the frequency, distribution, and prognostic significance of ABL mutations, we retrospectively analyzed a homogeneous cohort of late chronic phase CML patients who showed primary cytogenetic resistance to imatinib. PATIENTS AND METHODS: Using denaturing high-performance liquid chromatography (D-HPLC) and sequencing, we screened for ABL mutations in a total of 178 bone marrow and/or peripheral blood samples from 40 late chronic phase CML patients homogeneously treated with imatinib 400 mg/d, who did not reach a major cytogenetic response at 12 months. RESULTS: Mutations were found in 19 of 40 patients (48%). Mutations were already detectable by D-HPLC at a median of 3 months from the onset of therapy. The presence of a missense mutation was significantly associated with a greater likelihood of subsequent progression to accelerated phase/blast crisis (P = .0002) and shorter survival (P = .001). Patients carrying mutations falling within the P-loop seemed to have a particularly poor outcome in terms of time to progression (P = .032) and survival (P = .045). CONCLUSION: Our results show that, irrespective of the hematologic response, monitoring for emerging mutations in the first months of therapy may play a role in detecting patients with worse prognosis, for whom a revision of the therapeutic strategy should be considered.  相似文献   
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Quaking (QKI) is a tumor-suppressor gene encoding a conserved RNA-binding protein, whose expression is downregulated in several solid tumors. Here we report that QKI plays an important role in the immune response and suppression of leukemogenesis. We show that the expression of Qki is reduced in lipopolysaccharide (LPS)-challenged macrophages, suggesting that Qki is a key regulator of LPS signaling pathway. Furthermore, LPS-induced downregulation of Qki expression is miR-155-dependent. Qki overexpression impairs LPS-induced phosphorylation of JNK and particularly p38 MAPKs, in addition to increasing the production of anti-inflammatory cytokine IL-10. In contrast, Qki ablation decreases Fas expression and the rate of Caspase3/7 activity, while increasing the levels of IL-1α, IL-1β and IL-6, and p38 phosphorylation. Similarly, the p38 pathway is also a target of QKI activity in chronic lymphocytic leukemia (CLL)-derived MEC2 cells. Finally, B-CLL patients show lower levels of QKI expression compared with B cells from healthy donor, and Qki is similarily downregulated with the progression of leukemia in Eμ-miR-155 transgenic mice. Altogether, these data implicate QKI in the pathophysiology of inflammation and oncogenesis where miR-155 is involved.  相似文献   
48.
Adjuvant chemotherapy and endocrine therapy can induce early iatrogenic menopause or worsen pre-existing menopausal symptoms in breast cancer survivors (BCS). The second most frequent menopausal symptom after hot flushes is the genitourinary syndrome (GSM). Since hormone replacement therapy is contraindicated in BCS, vaginal laser might represent a new nonhormonal option for GSM. This study aims at evaluating the effectiveness of the fractional CO₂ vaginal laser for GSM in BCS compared with healthy women. This is a retrospective study on 135 postmenopausal women (45 BCS and 90 healthy women) who underwent fractional CO2 laser for GSM. Objective (VHI and VVHI) and subjective outcomes (VAS for dyspareunia and vaginal dryness and a pain questionnaire) were evaluated at baseline visit and at every follow-up visit. Subjective and objective parameters improved significantly in both groups after laser therapy. The improvement was progressive and long-lasting up to 12 months after the end of the treatment. No severe adverse events were observed during the treatment. Fractional CO₂ vaginal laser induces a significant and long-lasting improvement on GSM symptoms in BCS. However, this improvement is slower than in healthy women undergoing the same treatment. Laser therapy turns out to be safe and well-tolerated.  相似文献   
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BackgroundSexual dysfunction among psychotic patients is highly prevalent. However, most research has focused on antipsychotic side effects on sexual functioning.AimTo provide evidence by means of a systematic review of the literature about the impact of psychosis on sexual functioning among unmedicated patients.MethodsSystematic search of MEDLINE (PubMed), Scopus, and Google Scholar for studies that reported sexual functioning among psychotic patients, who were drug-naïve or drug-free for at least 3 weeks before the study. Studies were published in English language between January 1994 and October 2019. We used the approach recommended by PRISMA, and the selection process was carried out by 2 reviewers.OutcomesThe outcome measures were sexual function and sexual dysfunctions.ResultsA total of 734 articles were obtained, 658 were obtained after duplicates were removed, 612 were excluded after reading the title and abstract, and 46 were included for a complete review of the articles. 5 papers were finally included. A total of 770 cases were included in the systematic review. The prevalence of sexual dysfunction in psychosis varied from 16.8% to 70% and in ultra-high state was 50%. It is noteworthy that those ultra–high-risk (prodromal) patients who develop psychosis had higher rates of sexual impairment. Therefore, we found higher rates of sexual dysfunction among untreated patients, both psychotic and ultra-high risk patients, than healthy controls.Clinical ImplicationsThe assessment of sexual behavior should be a part of routine psychiatric examination not only in psychotic but also in ultra–high-risk patients.Strengths & LimitationsThis is the first systematic review about the impact of psychosis on sexual functioning among unmedicated patients. However, scarce and heterogeneous studies were identified.ConclusionsImpaired sexual functioning is common in the onset of psychosis (or during ultra–high-risk state) and prior to the beginning of treatment. This suggests that psychotic symptoms and sexual dysfunction may have common etiological pathways at the psychosocial and neurobiological levels.Vargas-Cáceres S, Cera N, Nobre P, et al. The Impact of Psychosis on Sexual Functioning: A Systematic Review. J Sex Med 2021;18:457–466.  相似文献   
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