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81.
Chlorhexidine susceptibility and Eagle effect in planktonic cells and biofilm of nosocomial isolates
Marchi Ana Paula Farrel Côrtes Marina Vásconez Noguera Saidy Rossi Flavia Levin Anna Sara Figueiredo Costa Silvia Perdigão Neto Lauro Vieira 《European journal of clinical microbiology & infectious diseases》2023,42(6):787-792
European Journal of Clinical Microbiology & Infectious Diseases - The aim of this study is to evaluate the chlorhexidine gluconate (CHG) susceptibility in both planktonic cells and biofilm of... 相似文献
82.
Dominici Carlo Nicotra Maria Rita Alemaà Stefano Bosman Cesare Castello Manuel A. Donfrancesco Alberto Gallo Pietro Natali Pier Giorgio 《Journal of neuro-oncology》1997,31(1-2):57-64
In neuroblastoma, high levels of mRNA for p14h
trkA
and p75
LNGFR
neurotrophin receptors are predictive of favorable outcome. Their evaluation by Northern blot, however, requires substantial amounts of tissue and this prevents their routine evaluation as well as the possibility for multicenter studies to be easily carried out. In an attempt to overcome these limitations, the feasibility and reliability of determining both neurotrophin receptors on cryostat sections by immunohistochemistry were assessed, and these findings were compared to those obtained from Northern blot analysis. Primary tumor samples from 28 untreated patients at all stages were evaluated by using H10 anti-p140
trkA
and ME20.4 anti-p75
LNGFR
mAbs. Although weak, positiveimmunostaining was found in 9 of 28 tumors for p140
trkA
and in 5 of 28 tumors for p75
LNGFR
. As compared to Northern blot, the concordance rate was 79% (22 of 28 cases) for p140
trkA
(p < 0.05) and 71% (20 of 28 cases) for p75
LNGFR
(p < 0.05). No case negative for Northern blot was found to be positive with immunohistochemistry. Since only high mRNA levels for both receptors have been shown to be clinically relevant, their immunohistochemical detection, although less sensitive than Northern blot, can be just as sufficient and reliable as a prognostic tool, and possibly with a better cost-benefit ratio. 相似文献
83.
Transdermal Delivery of Metoprolol by Electroporation 总被引:14,自引:0,他引:14
Electroporation, i.e., the creation of transient pores in lipid membranes leading to increased permeability, could be used to promote transdermal drug delivery. We have evaluated metoprolol permeation through full thickness hairless rat skin in vitro following electroporation with an exponentially decaying pulse. Application of electric pulses increased metoprolol permeation as compared to diffusion through untreated skin. Raising the number of twin pulses (300 V, 3 ms; followed after 1 s by 100 V, 620 ms) from 1 to 20 increased drug transport. Single pulse (100 V, 620 ms) was as effective as twin pulse application (2200 V, 1100 V or 300 V, 3 ms; followed after 1 s by 100 V, 620 ms). In order to investigate the effect of pulse voltage on metoprolol permeation, 5 single pulses (each separated by 1 min) were applied at varying voltages from 24 to 450 V (pulse time 620 ms). A linear correlation between pulse voltage and cumulative metoprolol transported after 4 h suggested that voltage controls the quantity of drug delivered. Then, the effect of pulse time on metoprolol permeation was studied by varying pulse duration of 5 single 100 V pulses from 80 to 710 ms (each pulse also separated by 1 min). Cumulative metoprolol transported after 4 h increased linearly with the pulse time. Therefore, pulse time was also a control factor of the quantity of drug delivered but to a lesser extent than the voltage at least at 100 V. The mechanisms behind improved transdermal drug delivery by electroporation involved reversible increased skin permeability, electrophoretic movement of drug into the skin during pulse application, and drug release from the skin reservoir formed by electroporation. Thus, electroporation did occur as shown by the increased transdermal permeation, on indicator of structural skin changes and their reversibility. Electroporation has potential for enhancing transdermal drug delivery. 相似文献
84.
Paul De Sutter Dmitri Dozortsev Philippe Vrijens Rita Desmet Marc Dhont 《Journal of assisted reproduction and genetics》1994,11(8):382-388
Purpose
Treatment of aged human oocytes by puromycin allows a high rate of parthenogenetic activation and development until the first cleavage division. This technique was used for the study of the chromosome complement of oocytes which remained unfertilized after in vitro fertilization. Three hundred four unfertilized oocytes were treated with 10 Μg/ml puromycin for 6–8 hr and further cultured for 12–15 hr.Results
Activation occurred in 90.5% of the oocytes. Heterozygous diploids with two pronuclei predominated (61%), which is in contrast to the mouse, where the majority of oocytes activated by puromycin are uniform haploids (89%).Conclusions
Therefore we conclude that puromycin treatment induces retention of the second polar body in human oocytes, unlike in mouse oocytes treated in the same way. Chromosome analysis performed on 182 oocytes suggested a nondisjunction (ND) rate for the second meiotic division of 12.7%. This is a low figure considering the fact that puromycin itself has been reported to induce nondisjunction. For the first meiotic division a ND rate of only 5.6% was found. This rate is lower than the one found in metaphase II arrested oocytes and we believe that this difference is due to the technical differences between the study of meiotic and that of mitotic chromosomes. 相似文献85.
Paola Queirolo MD Marco Ponte MD Marco Gipponi MD Ferdinando Cafiero MD Alberto Peressini MD Claudia Semino PhD Gabriella Pietra PhD Rita Lionetto MD Stefania Vecchio MD Iole Ribizzi MD Giovanni Melioli MD Mario R. Sertoli MD 《Annals of surgical oncology》1999,6(3):272-278
Background: On the basis of our previous experience, we designed this study to determine the activity and toxicity of outpatient treatment with autologous tumor-infiltrating lymphocytes (TIL) together with intermediate-dose recombinant interleukin-2 (rIL-2) and low-dose recombinant interferon alfa-2a (rIFN-2a), for patients with metastatic melanoma.Methods: Between April 1992 and October 1994, we processed 38 melanoma samples derived from 36 patients with metastases. Proliferative cultures of expanded lymphocytes (TIL) were infused only once into patients with metastatic melanoma. rIL-2 was administered subcutaneously for 1 month, starting on the day of TIL infusion, at an escalating dose of 6–18 × 106 IU/m2/day for the first week and at the maximum-tolerated dose for the subsequent 3 weeks and then, after a 15-day interval, for 1 week/month for 3 months. rIFN-2a was administered subcutaneously at 3 × 106 IU three times each week until progression.Results: Of 38 melanoma samples, 19 (50%) resulted in proliferative cultures and were infused. The median number of expanded lymphocytes was 18 × 109 (range, 1–43 × 109), and the median period of culture was 52 days (range, 45–60). rIL-2 was administered at doses ranging between 6 and 18 × 106 IU/m2/day. Toxicity was mild or moderate, and no life-threatening side effects were encountered. Two of 19 treated patients experienced complete responses of their metastatic sites (soft tissue), 10 had stable disease, and 7 showed progressive disease. The response rate was 11% (95% confidence interval, 2–35%).Conclusions: Outpatient treatment with TIL plus rIL-2 and rIFN-2a is feasible, although, within the context of the small sample size, the activity of the combination was no different from the reported activity of any of the components used alone. 相似文献
86.
Bánkfalvi Á Piffkó J Öfner D Dreier R Böcker W Werner K 《Pathology oncology research : POR》1996,2(1-2):71-77
Until recently the only way to rescue masked epitopes in routinely processed surgical pathological material was enzymatic
digestion. The use of heat for antigen retrieval, first by microwave irradiation, represents an important breakthrough in
immunohistochemistry. With the acceptance of microwave oven pretreatment, various modified techniques and alternative heating
methods have also been proposed. Wet autoclave pretreatment for tissue proteolysis is a highly reliable alternative to the
microwave antigen retrieval technique. It provides uniform heating of the slides, hence an even enhancement of staining intensity
in a variety of formalin-sensitive antigens, and it also offers consistent interlaboratory results. The method has been introduced
in routine diagnostic immunohistochemistry for the detection of estrogen-and progesterone receptors, L26-, Ki-67- and bcl-2
antigens and variable types of cytokeratins (1/5/10/11, 8, 13, 19). Experimentally, wet autoclaving can be used very successfully
for the immunophenotyping of p53 and mdm2 expression, for the detection of adhesion molecules (CD44, integrins) and some anti-inflammatory
molecules (annexins), among others. It has produced a substantial improvement in the visualisation of silver-stained nucleolar
organizer regionsassociated proteins (AgNORs) in routine paraffin sections and along with modified silver staining and standardized
AgNOR parameters assessed by image analysis. Wet autoclaving-based AgNOR staining has been proposed by a European multicentric
study group as the standardized method for AgNOR analysis in archival material. 相似文献
87.
88.
Karen M Emmons Rita M Butterfield Elaine Puleo Elyse R Park Ann Mertens Ellen R Gritz Maureen Lahti Fredrick P Li 《Journal of clinical oncology》2003,21(2):189-196
PURPOSE: This article describes baseline data collection and the intervention design of Partnership for Health, a smoking cessation intervention for smokers in the Childhood Cancer Survivors Study. The purpose of this article is to evaluate demographic, psychosocial, and cancer-related factors that are associated with smoking behavior and mediators of smoking cessation. PATIENTS AND METHODS: This study includes 796 smokers from the Childhood Cancer Survivors Study database who were diagnosed with cancer before the age of 21, had survived at least 5 years, and were at least 18 years of age at the time of the baseline survey. Correlates of smoking behaviors included smoking rate, number of recent quit attempts, and nicotine dependence; two key mediators of smoking cessation, readiness to quit smoking and self-efficacy, were also assessed. RESULTS: Participants smoked, on average, 14 cigarettes/day; 53.2% were nicotine dependent, and 58% had made at least one quit attempt in the past year. Smoking behaviors were primarily associated with demographic variables; mediators of cessation were primarily associated with age at cancer diagnosis and perceived vulnerability to smoking-related illnesses. Severity of psychologic symptoms was associated with increased smoking rate, high nicotine dependence, and low self-efficacy. Support for quitting was related to smoking rate, number of quit attempts, readiness to quit smoking, and self-efficacy. CONCLUSION: These findings indicate that many cancer survivors who smoke are receptive to smoking cessation interventions. Factors related to mediators of smoking cessation might be particularly good targets for intervention. 相似文献
89.
David Lee Shivakumar Chitturi James Kench Jacob George Steven Fuller Ken Bradstock Rita Lin Kai Ping Wong Noel Young 《Journal of Medical Imaging and Radiation Oncology》2003,47(2):117-120
Although transjugular liver biopsies are frequently performed in patients with impaired blood coagulation, their impact on effecting changes in clinical management has not been assessed. We reviewed our experience with 43 consecutive transjugular liver biopsies performed over 3 years (1998?2000) at Westmead Hospital, Sydney, Australia. The technical success, procedural complication rates and subsequent management of these patients were ascertained from the medical case records. Forty‐two (28 men) patients were studied. The indications for liver biopsy were as follows: assessment of hepatitis/cirrhosis status (n = 21), evaluation of liver dysfunction following bone marrow transplantation (n = 19) and miscellaneous (n = 2). All liver biopsies were performed with a Cook 20‐G transjugular cutting needle device. Adequate histological samples were obtained in 42 (98%) of the 43 biopsies performed. The pre‐biopsy diagnoses were confirmed by histology in 28 cases (65%). A change in clinical diagnosis was observed in 12 (28%) patients, and there were changes to subsequent management in all 12 patients. Four patients developed procedural complications, including small neck haematomas in two patients and a self‐limiting biliary fistula in one. The only major complication was an extracapsular bleed from a hepatic laceration. This patient required emergency surgery but recovered. Transjugular liver biopsies can be effectively and safely performed in high‐risk patients with impaired coagulation. They aid accurate histological appraisal of liver dysfunction in these patients and influence clinical decision‐making. 相似文献
90.
Silvana Chiara Maria Teresa Nobile Maura Vincenti Rita Lionetto Alberto Gozza Maria Cristina Barzacchi Ornella Sanguineti Lazzaro Repetto Riccardo Rosso 《Cancer chemotherapy and pharmacology》1998,42(4):336-340
To evaluate toxicity and efficacy of chemotherapy in elderly patients (≥65 years of age) with advanced colorectal cancer,
data from two consecutive trials conducted between 1984 and 1995 at the National Institute for Cancer Research were analysed
comparing the results of treatment in those 65 years of age or older and in those younger than 65 years. Of 215 patients recruited,
82 elderly patients (median age 70 years, median performance status 1) received one of the following regimens based on 5-fluorouracil
(5-FU): (1) weekly 5-FU 600 mg/m2 i.v. bolus (30 patients); (2) weekly 5-FU 600 mg/m2 bolus plus leucovorin (LV) 500 mg/m2 2-h i.v. infusion (28 patients); (3) Weekly 5-FU 2600 mg/m2 24-h continuous i.v. infusion plus LV 100 mg 4-h i.v. infusion and 50 mg orally every 4 h for five doses (24 patients). Overall,
1071 chemotherapy cycles were administered with a median number of 12 courses per patient. The main side effects were diarrhoea,
observed in 38% of patients, stomatitis in 24% of patients and hand-foot syndrome in 13% of patients, and haematological toxicity
affected only 15% of patients. No patient suffered grade IV toxicity. In three patients chemotherapy was discontinued because
of toxicity (two patients suffered grade III diarrhoea, one patient grade III hand-foot syndrome). No significant difference
in toxicity was evident between patients older than or younger than 65 years. Analysis of median dose intensity demonstrated
no difference between the two groups. Overall objective response was observed in 18% (95% confidence limits 11–29) of elderly
patients (15/82) in comparison with 23% (95% CL 17–32) of patients <65 years of age (31/133 pts). In conclusion, chemotherapy
in elderly patients with advanced colorectal cancer is a safe and effective treatment with acceptable toxicity and comparable
objective response rates.
Received: 6 January 1998 / Accepted: 27 February 1998 相似文献