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131.
Brevinin‐2 related peptide (B2RP; GIWDTIKSMG10KVFAGKILQN20L.NH2), first isolated from skin secretions of the mink frog Lithobates septentrionalis, shows broad‐spectrum antimicrobial activity but its therapeutic potential is limited by moderate hemolytic activity. The peptide adopts an α‐helical conformation in a membrane‐mimetic solvent but amphipathicity is low. Increasing amphipathicity together with hydrophobicity by the substitutions Lys16→Leu and Lys16→Ala increased hemolytic activity approximately fivefold without increasing antimicrobial potency. The substitution Leu18→Lys increased both cationicity and amphipathicity but produced decreases in both antimicrobial potency and hemolytic activity. In contrast, increasing cationicity of B2RP without changing amphipathicity by the substitution Asp4→Lys resulted in a fourfold increase in potency against Escherichia coli [minimal inhibitory concentration (MIC) = 6 μm ) and twofold increases in potency against Staphylococcus aureus (MIC = 12.5 μm ) and Candida albicans (MIC = 6 μm ) without changing significantly hemolytic activity against human erythrocytes (LC50 = 95 μm ). The emergence of antibiotic‐resistant strains of the Gram‐negative bacterium Acinetobacter baumannii constitutes a serious risk to public health. B2RP (MIC = 3–6 μm ) and [Lys4]B2RP (MIC = 1.5–3 μm ) potently inhibited the growth of nosocomial isolates of multidrug‐resistant Acinetobacter baumannii. Although the analogs [Lys4, Lys18]B2RP and [Lys4, Ala16, Lys18]B2RP showed reduced potency against Staphylococcus aureus, they retained activity against Acinetobacter baumannii (MIC = 3–6 μm ) and had very low hemolytic activity (LC50 > 200 μm ). 相似文献
132.
El-Sayed E Larsson JO Persson HE Rydelius PA 《Journal of the American Academy of Child and Adolescent Psychiatry》2002,41(7):811-819
OBJECTIVE: To evaluate whether cortical activity recorded during attentional load in children with ADHD is different compared with controls. METHOD: Quantitative electroencephalography (QEEG) was performed at open eyes and during performance of the Continuous Performance Task. RESULTS: Children with ADHD showed an altered pattern of QEEG activity, especially during the attentional load task, with increased slow cortical activity (mainly over the frontal areas) and decreased fast cortical activity. CONCLUSIONS: The findings indicate a different arousal level in children with ADHD, which could be due to a delay in functional cortical maturation. To evaluate the clinical importance of these findings, a longitudinal follow-up will be conducted. 相似文献
133.
Background Pressure ulcers are a potential complication for intensive care patients and their prevention is a major issue in nursing care. Therefore, this study aims to assess pressure ulcer prevalence in intensive care patients, patients' characteristics and preventive measures related to pressure ulcer prevalence in intensive care patients and to determine the most common body sites of pressure ulcers.
Method The research design was a cross-sectional study. The sample consisted of 1760 patients (298 in 2002, 408 in 2003, 453 in 2004, 368 in 2005 and 233 participants in 2006) from surgical, medical and interdisciplinary intensive care.
Results The results revealed a mean prevalence rate of ±30% from 2002 to 2005 while it considerably decreased down to 16.2% in 2006. Half of the pressure ulcers were of grade 1. Furthermore, a significant relation was found between the presence of pressure ulcers and age ( P ≤ 0.022), Braden score ( P ≤ 0.01) and bowel incontinence ( P ≤ 0.01).
Conclusion It is crucial to select appropriate and applicable preventive material/devices and nursing care measures. Moreover, factors related to the presence of pressure ulcers should be taken into consideration in order to prevent development of further pressure ulcers. 相似文献
Method The research design was a cross-sectional study. The sample consisted of 1760 patients (298 in 2002, 408 in 2003, 453 in 2004, 368 in 2005 and 233 participants in 2006) from surgical, medical and interdisciplinary intensive care.
Results The results revealed a mean prevalence rate of ±30% from 2002 to 2005 while it considerably decreased down to 16.2% in 2006. Half of the pressure ulcers were of grade 1. Furthermore, a significant relation was found between the presence of pressure ulcers and age ( P ≤ 0.022), Braden score ( P ≤ 0.01) and bowel incontinence ( P ≤ 0.01).
Conclusion It is crucial to select appropriate and applicable preventive material/devices and nursing care measures. Moreover, factors related to the presence of pressure ulcers should be taken into consideration in order to prevent development of further pressure ulcers. 相似文献
134.
Background: Pressure ulcers remain a common health problem worldwide within the different health‐care settings, especially in intensive care settings. Aims: The aims of this were to systematically assess the recent prevalence and incidence of pressure ulcers in intensive care patients (2000–2005), the factors related to pressure ulcer prevalence and incidence and the methodological rigour of studies about pressure ulcer prevalence and incidence in intensive care patients. Methods: The research design involved a review of literature for the period of 2000 to 2005, focused on the prevalence and incidence of pressure ulcers in intensive care patients. Results: The analysis of published papers revealed variations in pressure ulcer prevalence in intensive care settings ranging from 4% in Denmark to 49% in Germany, while incidence ranged from 38% to 124%. There was a wide variation in the prevalence and incidence of pressure ulcers in intensive care patients as evidenced in the studies examined. There is also a gap between theory and practice in the prevention and treatment of pressure ulcers which needs to be addressed. Conclusion: Further research is needed regarding the effectiveness of nursing care on pressure ulcer development and into treatments that may successfully prevent their occurrence in intensive care patients. 相似文献
135.
Intensive efforts are underway worldwide to develop anticancer and antimicrobial agents. Therefore, a novel series of pyrido[2,1-b]benzo [d]thiazole and 2-(benzo [d] thiazol-2-ylamino)pyrimidine derivatives was synthesized. The synthesized compounds were evaluated for their anticancer activity. Among the tested compounds, compounds 3a, 3b, and 7 exhibited more cytotoxic action than the control drug doxorubicin (CAS 23214-92-8; IC50: 52 microg/ml). Compound 7 was the most potent cytotoxic, with an IC50 of 42.55 pg/ ml, while compounds 3a and 3b induced high cytotoxic action with IC50 values of 50.15 pg/ml and 50.45 pg/ml, respectively. Moreover, the synthesized compounds were screened for their antibacterial and antifungal activities. Compound 6 exhibited moderate antifungal activity against C. albicans with a minimum inhibitory concentration of 125 pg/ml. 相似文献
136.
Some novel 4-(quinolin-1-yl)-benzenesulfonamide and 4-(pyrimido[4,5-b]quinolin-10-yl)-benzenesulfonamide derivatives have been synthesized. All the newly synthesized target compounds were subjected to in vitro cytotoxic screening to be evaluated for their anticancer activity against Ehrlich ascites carcinoma cells. Among these new compounds, compounds 9a, 11, 12b, 18 and, in particular, 19 showed promising in vitro cytotoxic activity compared with doxorubicin (CAS 23214-92-8) as a reference drug. Moreover, compound 8 exhibited in vivo radioprotective activity against gamma-irradiation in mice. 相似文献
137.
Despite the extensive use of pectoralis major flaps in reconstructive surgery, certain pectoralis major musculocutaneous flaps
may suffer from partial distal necrosis. The aim of the present study was to investigate the origin, length, and external
diameter of its arterial pedicles to provide an anatomical basis for alternative techniques in reconstructive surgery. Thirty
pectoral region specimens, pertaining to 14 fresh human adult cadavers and one stillbirth, were dissected, after retrograde
injection of the brachial artery with red latex in pursuit of this aim. The thoracoacromial trunk (TAT) was the main nourishing
vessel, arising from the first and the second parts of the axillary artery in 60% and 40%, respectively. The proximal segment
was constantly supplied by the clavicular and the deltoid branches of the TAT, supplemented by its pectoral branch in 30%
and the superior thoracic artery in 23.3%. The distal segment was constantly supplied by the lateral perforating branches
of the anterior intercostal arteries and the perforating branches of the internal thoracic artery. The pectoral branch of
both the TAT (P-TAT), and the axillary artery (PA) and the lateral thoracic artery participated in 90%, 66.7%, and 40%, respectively.
Additionally, an arterial pedicle, from the arterial plexus inside the pectoralis minor muscle, was observed in 4/30 (13.3%).
The clavicular and pectoral branches of the TAT are reliable pedicles for raising the proximal and distal segments of muscle
flaps, respectively. The pectoral branch of axillary artery may be an alternative pedicle in the absence of P-TAT. 相似文献
138.
Ahmad M. Mansour Igor Kozak Ali Osman Saatci Francisco J. Ascaso Laura Broc Maurizio Battaglia Nuria Olivier Pablo Gili Jay Chhablani Thomas R. Hedges Ana Honrubia Laura Gutierrez Giacomo Panozzo Jaume Catal Jesús Díaz Elisa Carreras Sibel Kadayifcilar Eman S. Al Kahtani Sami H. Uwaydat Luiz H. Lima Hana A. Mansour Hashim Ali Khan Thomas M. Aaberg Jr Jerald A. Bovino Alex P. Hunyor 《Eye (London, England)》2021,35(2):425
Background/ObjectivesTo analyze the ophthalmic characteristics of congenital prepapillary vascular loop (PVL) and to propose a new morphologic classification dividing the loops into six types.Subjects/MethodsCollaborative multinational multicentre retrospective study of PVL cases.ResultsThere was a total of 49 cases (61 eyes), 37 unilateral (75.5%) and 12 bilateral (24.5%), 32 arterial type (65.3%) and 18 venous type (36.7%) (one patient had either kind in each eye). The mean number of loops per eye was 2.7 (range, 1–7). The loops were asymptomatic in 42 cases (85.7%). Other findings included: the presence of cilioretinal artery (14 cases), retinal vascular tortuosity (26 cases), amaurosis fugax (1 case), branch retinal artery occlusion (1 case) and vitreous haemorrhage (3 cases). Six morphologic loop types could be discerned based on elevation (flat vs. elevated), shape (figure of 8 or corkscrew with hyaline sheath), number (multiple or single), location (central or peripheral), lumen size (arterial vs. arteriolar) and presence of vascular tortuosity or vitreous traction.ConclusionsPVL are usually asymptomatic and can be divided into six morphologic types with different pathogenesis during early embryogenesis.Subject terms: Anatomy, Physiology 相似文献
139.
Adel Gomaa Mohsen Elshenawy Noha Afifi Eman Mohammed Romany Thabit 《International immunopharmacology》2010,10(11):1406-1414
The anti-arthritic and anti-inflammatory effects of dipyridamole and the possible involvement of NO in the dipyridamole action are not yet clear. The aim of this study was to evaluate the effects of dipyridamole alone and in combination with either the nitric oxide donor, sodium nitroprusside (SNP) or the non-selective nitric oxide synthase inhibitor, L-NG- monomethyl arginine (L-NMMA), on pathogenesis of adjuvant-induced arthritis model in rats. The results of the present work showed that prophylactic administration of dipyridamole alone and dipyridamole administration in combination with either low dose of SNP or L-NMMA significantly ameliorated pathogenesis of adjuvant arthritis in rats as evidenced by significant decrease in arthritis index, hind paws volume, loss of body weight, hyperalgesia compared with control vehicle (1% DMSO) treated adjuvant arthritic rats. Inflammatory cellular infiltrate in synovium of ankle joint and pannus formation were also markedly inhibited. Interleukin-10(IL-10) levels were significantly increased in these groups of animals. In contrast, a high dose of SNP counteracted the anti-inflammatory and anti-arthritic effects of dipyridamole. The inhibitory effect of therapeutic administration of dipyridamole alone on adjuvant arthritis syndrome was not significantly different from that of vehicle administration. In conclusion, dipyridamole has prophylactic but not therapeutic anti-arthritic and anti-inflammatory effects that appear to be dependent on inhibition of NO synthase. A synergistic combination between dipyridamole and NO synthase inhibitor or low dose of NO donor may have prophylactic and therapeutic values in autoimmune diseases like RA. 相似文献
140.
Effects of Ethanol on Hexose Uptake by Cultured Rat Brain Cells 总被引:2,自引:0,他引:2
Sant P. Singh MD Ann K. Snyder PhD Svetlana Eman BS MS 《Alcoholism, clinical and experimental research》1990,14(5):741-745
The effects of ethanol on hexose uptake by glial cells was investigated using primary cultures prepared from term rat fetuses. Specific 3H 2-deoxy-D-glucose (2DG) uptake was significantly reduced by a 4-hr exposure to ethanol at concentrations of 25, 50, and 100 mM, but not 200 or 300 mM. The inhibitory effect of 50 mM ethanol increased with the duration of exposure, with 2DG uptake inhibited by 36% after 18 hr. Astrocytes cultured from the brains of term fetuses of rats fed ethanol during pregnancy showed essentially the same 2DG uptake response to in vitro ethanol treatment. Kinetics of 2DG uptake showed a significant decrease of Vmax in the presence of ethanol. No interaction was found between ethanol and insulin, which stimulated 2DG uptake and protein content of the cultures. The data suggest that ethanol can modulate hexose uptake by astrocytes cultured from fetal rat brain. However, insulin actions on glial cells were not affected by ethanol. 相似文献