Liposome-cell interaction: transfer and intracellular release of a trapped fluorescent marker

When small, unilamellar lipid vesicles containing a high concentration of the fluorescent dye 6-carboxyfluorescein are incubated with either frog retinas or human lymphocytes, fluroescence distributes widely throughout each cell. Since "self-quenching" largely prevents the dye from fluorescing as long as it remains sequestered in vesicles, it is clear that a considerable amount of dye is released from the vesicles and diluted into the much larger volume of the cell.     

Polymeric HVDC Cable Design and Space Charge Accumulation. Part 1: Insulation/Semicon Interface

From theory and experiments, it can be deduced that materials for DC applications should not accumulate a large amount of space charge if accelerated degradation of the insulation system is to be avoided. Therefore, the characterization of DC insulation must take into account the evaluation of space charge accumulation. This cannot be done exhaustively without taking a system approach considering both the semiconductive material and the insulation, in particular, the properties of the semicon/insulation interface. The latter interface, in fact, plays a major role in space charge injection/accumulation in the insulation bulk. Having analyzed different semiconductive and insulating materials candidate for HVDC cable applications, the best solution to be exploited for HVDC cable design would be the combination showing a high threshold for space charge accumulation, a small rate of charge accumulation as a function of electric field and a small activation energy, i.e., a space charge amount less dependent on temperature. Therefore, space charge measurements will provide important information to cable material manufacturers with the aim of tailoring insulation and semicon specifically for HVDC application and, thus, improving the reliability of polymeric cables.     

IN VITRO ANTIOXIDANT AND ANTICANCER ACTIVITIES OF EXTRACTS FROM A FERMENTED FOOD

Solvent extracts were prepared from Manda Enzyme®, one of the fermented health foods, and their activities of radical scavenging and cancer cell growth inhibition were evaluated. Manda Enzyme® was extracted with 55% ethanol, and then fractionated into n‐hexane, chloroform, ethyl acetate, methanol‐soluble and methanol‐insoluble fractions. The antioxidant activities were in the order chloroform > ethyl acetate > other fractions and of each fraction were positively related to the amount of total phenolics and the intensity of brown color. The cancer cell growth inhibitory activities were in the order n‐hexane > chloroform > other fractions. Proliferation of HRT‐18, HCT‐48 and HepG2 human cancer cells was inhibited by the treatment of the n‐hexane fraction of Manda Enzyme® at a concentration of 400 μg/mL to the extent of 75, 89 and 90%, respectively. From these results, it is considered that Manda Enzyme® has chemically different ingredients showing strong antioxidant and anticancer activity in vitro.     

Laparoscopy-assisted and -prepared hysterectomy. A series of 80 cases

OBJECTIVE: Our objective was to determine the interest of laparoscopic assisted vaginal hysterectomy. STUDY DESIGN: Between January 1991 to december 1994, 80 patients had laparoscopically assisted vaginal hysterectomy. We reviewed with particular emphasis characteristic indications, complications. RESULTS: Eighty were performed as laparoscopically assisted vaginal hysterectomy. 14 patients (17.5%) had laparotomy conversion; because of size of uterus in 3 cases, suspected ovarian tumor in 3 cases. Pelvic adherences in 4 cases, urinary tract injuries in 1 case, hypercapnia in 1 case, hemorrhage in 2 cases. 9 patients experienced febrile morbidity and 1 urinary infection. 1 patient received 2 units of packed red blood cells. The hospital stay was 5 days for laparoscopically assisted vaginal hysterectomy versus 5.9 for laparotomic hysterectomy. CONCLUSION: Laparoscopically assisted vaginal hysterectomy offers a technique to convert certain abdominal hysterectomies into vaginal hysterectomies with a 17.5% laparoconversion rate.     

Protective effect of lysozyme-galactomannan or lysozyme-palmitic acid conjugates against Edwardsiella tarda infection in carp, Cyprinus carpio L

The protective effect of lysozyme-galactomannan or lysozyme-palmitic acid conjugates orally administered to carp, Cyprinus carpio L. was investigated using a virulent strain of Gram-negative Edwardsiella tarda isolated from an infected fish. Lysozyme-galactomannan conjugate was prepared through controlled Maillard reaction. Lysozyme-palmitic acid conjugate was prepared through base-catalyzed ester exchange using N-hydroxysuccinimide ester of palmitic acid. The conjugates provided substantial protection to carp infected with a Gram-negative bacteria fish pathogen E. tarda NG 8104. Lytic activities of lysozyme conjugates with galactomannan and palmitic acid were about 80 and 71% of native lysozyme using Micrococcus lysodeikticus as a substrate. Feeding with lysozyme conjugates, for 8 days, significantly enhanced fish protection against E. tarda infection. The survival rate was 30% for lysozyme-galactomannan conjugate treated fish and 20% for lysozyme-palmitic acid conjugate treated fish after 6 days cultivation while all control fish died within 3 days. On the other hand, a recovery rate of 40% after 6 days was observed in the fish group that were fed lysozyme-palmitic acid conjugate 3 and 2 h before and after E. tarda challenge, respectively, and for 6 consecutive days. The results of this work show the possibility of utilizing lysozyme conjugates with galactomannan or palmitic acid as a therapeutic for infection in fish.     

Regulation in the heart field of zebrafish

In many vertebrates, removal of early embryonic heart precursors can be repaired, leaving the heart and embryo without visible deficit. One possibility is that this 'regulation' involves a cell fate switch whereby cells, perhaps in regions surrounding normal progenitors, are redirected to the heart cell fate. However, the lineage and spatial relationships between cells that are normal heart progenitors and those that can assume that role after injury are not known, nor are their molecular distinctions. We have adapted a laser-activated technique to label single or small patches of cells in the lateral plate mesoderm of the zebrafish and to track their subsequent lineage. We find that the heart precursor cells are clustered in a region adjacent to the prechordal plate, just anterior to the notochord tip. Complete unilateral ablation of all heart precursors with a laser does not disrupt heart development, if performed before the 18-somite stage. By combining extirpation of the heart precursors with cell labeling, we find that cells anterior to the normal cardiogenic compartments constitute the source of regulatory cells that compensate for the loss of the progenitors. One of the earliest embryonic markers of the premyocardial cells is the divergent homeodomain gene, Nkx2.5. Interestingly, normal cardiogenic progenitors derive from only the anterior half of the Nkx2.5-expressing region in the lateral plate mesoderm. The posterior half, adjacent to the notochord, does not include cardiac progenitors and the posterior Nkx2.5-expressing cells do not contribute to the heart, even after ablation of the normal cardiogenic region. The cells that can acquire a cardiac cell fate after injury to the normal progenitors also reside near the prechordal plate, but anterior to the Nkx2.5-expressing domain. Normally they give rise to head mesenchyme. They share with cardiac progenitors early expression of GATA 4. The location of the different elements of the cardiac field, and their response to injury, suggests that the prechordal plate supports and/or the notochord suppresses the cardiac fate.     

The effects of cytotoxic entorhinal lesions and electrolytic medial septal lesions on the acquisition and retention of a spatial working memory task

This study assesses how social desirability affects responses in clinical self-report inventories. Six hundred items gathered from four normal personality questionnaires were adapted to devise a pre-experimental personality questionnaire (pre-EMHQ). Results obtained from administering Ko's Mental Health Questionnaire (KMHQ) and the pre-EMHQ to separate samples were the proportion of individuals answering "true" to each item (i.e., P(t)) and the social desirability scale value (i.e., SDSV) of each item. The Experimental Mental Health Questionnaire (EMHQ) was established from the pre-EMHQ by closely matching the P(t)s and the SDSVs of the two questionnaires. Administering the KMHQ and the EMHQ concurrently to another sample provided results for factor analysis and other statistical analyses. The SDSVs and the P(t)s for each of the KMHQ items certainly displayed a linearly increasing relation. The two sets of corresponding subscales also correlated significantly. By applying the polynomial regression analysis, the tendency to score might be expressed as a quadratic function of SDSVs. Two iterative principal-factor analyses of the two sets of subscales each resulted in two factors, and Factor 1 is similar in both the KMHQ and the EMHQ. In brief, social desirability plays a critical role in affecting responses in a clinical self-report inventory. The factors involved and suggestions proposed will be of value for further research.     

Effect of local standards on the implementation of national guidelines for asthma: primary care agreement with national asthma guidelines

In vivo electrophysiological assays in anesthetized rats have been used to compare the effects of the 5HT1B/1D receptor agonist, naratriptan, on central trigeminal nociceptive processing from dural and cutaneous inputs with its effects on nociceptive processing in the spinal cord. Naratriptan inhibited responses of single trigeminal neurons, to noxious electrical and mechanical stimulation of the dura and face, dose dependently by a maximum of 67+/-3% and 70+/-18%, respectively, at 3 mg kg(-1) i.v. In contrast, naratriptan did not affect spinal dorsal horn neuronal responses to noxious mechanical stimulation of the hind-paw. These findings suggest that 5HT1B/1D receptors have differential effects on nociceptive processing in the trigeminal versus spinal dorsal horns and provide a potential explanation for the lack of general analgesic effects of brain penetrant 5HT(1B/1D) agonist antimigraine drugs.