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71.

Objective:

To determine the in vitro toxicity of different concentrations of sevoflurane in cells exposed to X-ray.

Methods:

The genotoxic effects of sevofluorane were studied by means of the micronucleus test in cytokinesis-blocked cells of irradiated human lymphocytes. Subsequently, its cytotoxic effects on PNT2 (normal prostate) cells was determined using the cell viability test (MTT) and compared with those induced by different doses of X-rays.

Results:

A dose- and time-dependent cytotoxic effect of sevofluorane on PNT2 cells was determined (p >0.001) and a dose-dependent genotoxic effect of sevofluorane was established (p >0.001). Hovewer, at volumes lower than 30 μL of sevofluorane at 100%, a non-toxic effect on PNT2 cells was shown.

Conclusion:

Sevofluorane demonstrates a genotoxic capacity as determined in vitro by micronucleus test in cytokinesis-blocked cells of irradiated human lymphocytes.  相似文献   
72.
73.
Shoulder dystocia has no consensus definition or management algorithm. Its incidence ranges from 0.2% to 3% and its occurrence is unpredictable. Risk factors for shoulder dystocia may include macrosomia, maternal diabetes, operative vaginal delivery, history of macrosomic infant or shoulder dystocia, labor abnormalities, post-term pregnancy, maternal obesity, advanced maternal age, fetal anthropometric variations, and male fetal gender. Once identified, multiple maneuvers can be applied in a stepwise fashion in an attempt to alleviate the dystocia. While training clinicians to manage shoulder dystocia is difficult because of its rare occurrence and lack of standardized management, all clinicians must be able to manage shoulder dystocia at any time.  相似文献   
74.
75.
Palladium-catalyzed reactions are among the most commonly used procedures in organic synthesis. The products have a range of uses, including as intermediates in total synthesis and as screening compounds for drug discovery or agrochemical projects. Despite the known and potentially deleterious effects of low-level metal impurities in biological assays, the quantification of metal remaining in reaction products to verify the effective removal of the transition element is rarely reported. Using palladium as an exemplar, we describe a pilot study that for the first time quantifies residual metal levels in reaction products following increasingly rigorous purification protocols. Our results demonstrate that significant levels of residual palladium can remain in isolated reaction products following chromatographic purification, and only by using a subsequent metal scavenging step are they reliably reduced to a low level. Finally, we provide a set of simple guidelines that should minimize the potential for issues associated with residual palladium in reaction products.  相似文献   
76.
Chlorpromazine is known to produce both systemic phototoxic and photoallergic reactions. However, it may also cause photoallergic contact dermatitis and, albeit exceptionally, allergic contact dermatitis (ACD). We present a series of photoallergic contact dermatitis and ACD to chlorpromazine diagnosed at a tertiary centre cutaneous allergy unit between 1980 and 2019.  相似文献   
77.
78.
Postdiagnosis diet and alcohol consumption may be associated with cancer prognosis, recurrence and mortality. Our aim was to investigate food, nutrient and alcohol intake variations between before and after cancer diagnosis and their determinants in a prospective cohort. Subjects (n = 696) were incident cancer cases diagnosed in the NutriNet‐Santé cohort between 2009 and 2016. Food, nutrient and alcohol intakes were prospectively collected using repeated nonconsecutive 24‐hr dietary records since subjects' inclusion (i.e. an average of 2 y before diagnosis). Mean number of dietary records per subject was 5.9 before and 8.1 after diagnosis. All dietary data before and after diagnosis were compared by mixed models. Factors associated with the main dietary changes observed were also investigated using multivariable logistic regressions. We observed a decrease in intakes of vegetables (mean decrease in intake in patients who decreased their intake=‐102.4 ± 79.8 g/d), dairy products (–93.9 ± 82.8 g/d), meat/offal (–35.5 ± 27.8/d), soy products (–85.8 ± 104.1 g/d), sweetened soft drinks (–77.9 ± 95.4 g/d), and alcoholic drinks (–92.9 ± 119.9 g/d), and an increase in broths (42.1 ± 34.9 g/d) and fats/sauces (18.0 ± 13.4 g/d). We observed a decrease in energy intake (–377.2 ± 243.5 kcal/d) and in intakes of alcohol (–7.6 ± 9.4 g/d) proteins (–17.4 ± 12.5 g/d), and several vitamins (p < 0.05) and micronutrients (p < 0.05). Conversely, lipid (19.4 ± 14.6 g/d), SFA (9.3 ± 7.0 g/d), MUFA (8.3 ± 6.3 g/d) and vitamin E (3.9 ± 3.3 mg/d) intakes increased after diagnosis. This large prospective study suggests that cancer diagnosis is a key period for nutritional changes. It highlights some healthy behaviors such as a decrease in alcohol and sweetened drink consumption, but also less favorable trends, such as a decrease in vegetable consumption and in many vitamin and mineral intakes. These results provide insights to identify and target recommendations to put forward for better nutritional care of cancer survivors.  相似文献   
79.

Background.

In the neoadjuvant setting, changes in the proliferation marker Ki67 are associated with primary endocrine treatment efficacy, but its value as a predictor of response to chemotherapy is still controversial.

Patients and Methods.

We analyzed 262 patients with centralized basal Ki67 immunohistochemical evaluation derived from 4 GEICAM (Spanish Breast Cancer Group) clinical trials of neoadjuvant chemotherapy for breast cancer. The objective was to identify the optimal threshold for Ki67 using the receiver-operating characteristic curve method to maximize its predictive value for chemotherapy benefit. We also evaluated the predictive role of the defined Ki67 cutoffs for molecular subtypes defined by estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2).

Results.

A basal Ki67 cutpoint of 50% predicted pathological complete response (pCR). Patients with Ki67 >50% achieved a pCR rate of 40% (36 of 91) versus a pCR rate of 19% in patients with Ki67 ≤50% (33 of 171) (p = .0004). Ki67 predictive value was especially relevant in ER-HER2− and ER-HER2+ patients (pCR rates of 42% and 64%, respectively, in patients with Ki67 >50% versus 15% and 45%, respectively, in patients with Ki67 ≤50%; p = .0337 and .3238, respectively). Both multivariate analyses confirmed the independent predictive value of the Ki67 cutpoint of 50%.

Conclusion.

Basal Ki67 proliferation index >50% should be considered an independent predictive factor for pCR reached after neoadjuvant chemotherapy, suggesting that cell proliferation is a phenomenon closely related to chemosensitivity. These findings could help to identify a group of patients with a potentially favorable long-term prognosis.

Implications for Practice:

The use of basal Ki67 status as a predictive factor of chemotherapy benefit could facilitate the identification of a patient subpopulation with high probability of achieving pathological complete response when treated with primary chemotherapy, and thus with a potentially favorable long-term prognosis.  相似文献   
80.
Lonomia achelous caterpillar, Lepidoptera distributed along some South American countries, induces a hemorrhagic syndrome in people who come into contact with its bristles. A clinical characteristic in these patients is that fresh healed wounds are re-opened and bleed. In order to explain this symptomatology, we evaluated the effect of Lonomin V (a protein isolated from L. achelous hemolymph), on some functional properties of fibronectin, which in turn plays an important role in the hemostasis. The effect of Lonomin V on fibronectin was studied by SDS-PAGE in reduced condition, binding to gelatin and heparin, crosslinking to fibrin and platelet adhesion. Formation of degradation products of 120, 66, 50, 40 and 29 kDa, some of which retain affinity to heparin and gelatin were observed; however, the fibronectin degradation fragments presented a significant decrease of crosslinking capacity to fibrin and platelet adhesion, suggesting that the proteolysis of fibronectin by Lonomin V induces changes in its crosslinking sites and on platelet receptors. These findings might partially explain the wound dehiscence observed in the patients. Due to its effect on adhesive proteins with concomitant impairment of some functional properties, Lonomin V might be useful for cellular adhesion studies involved in hemostasis such as platelet adhesion.  相似文献   
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