Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Skin Window Technique”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources
PubMed1977

Stimulated neutrophil locomotion: chemokinesis and chemotaxis.

All leukocytes are capable of responding chemotactically (oriented locomotion) and chemokinetically (stimulated nondirected or random locomotion) to a variety of chemical agents. A brief review of the in vitro and in vivo methods of studying neutrophil movement and our present knowledge of chemotactic factors is presented as well as a discussion on the mechanisms of stimulated movement. Two clinically important instances of defects in neutrophil movement, ie, the Chédiak-Higashi syndrome and a case of actin dysfunction, are herein described.

Ascorbic Acid↗
PubMed1975

In vitro synthesis of lysozyme by human and mouse tissues and leucocytes.

Previous studies have shown that lysozyme can be detected in many body fluids, in extracts of tissues, and also in granulocytes, monocytes and macrophages. However, the sites of synthesis of lysozyme have not been defined. In the present report, the synthesis of lysozyme by tissues, and by defined cell populations cultured in vitro has been studied by detecting the incorporation of 14-C-labelled amino acids into lysozyme. This method detects only lysozyme newly synthesized during the incubation of the specimen and therefore shows unequivocally which tissues and cell types are capable of lysozyme synthesis. The validity of the method has been shown by parallel studies using an independent method to detect lysozyme production in vitro. In studies in humans and mice, lysozyme synthesis has been demonstrated in the mucosa of the respiratory and gastrointestinal tracts, and in lymphoid organs. In studies of defined cell populations, monocytes and macrophages (mononuclear phagocytes) have been shown to synthesize lysozyme. Granulocytes from peripheral blood contain lysozyme but do not synthesize it, and lymphocytes neither contain nor synthesize lysozyme. The present findings provide further evidence that lysozyme has an important role in the defence of the host against micro-organisms, and the findings suggest that lysozyme may reach its target by several routes. At an intracellular level it is delivered from lysosomes into the phagocytic granules of granulocytes and macrophages. Local synthesis of the mucous membranes contributes lysozyme to secretions. Synthesis and secretion by mononuclear phagocytes which reach a tissue in response to an inflammatory stimulus contribute lysozyme to the exudate, and the release of lysozyme from breakdown of granulocytes has the same effect.

Animals↗
PubMed2002

Comparison of IgG diffusion and extracellular matrix composition in rhabdomyosarcomas grown in mice versus in vitro as spheroids reveals the role of host stromal cells.

The tumour extracellular matrix acts as a barrier to the delivery of therapeutic agents. To test the hypothesis that extracellular matrix composition governs the penetration rate of macromolecules in tumour tissue, we measured the diffusion coefficient of nonspecific IgG in three rhabdomyosarcoma subclones growing as multicellular spheroids in vitro or as subcutaneous tumours in dorsal windows in vivo. In subcutaneous tumours, the diffusion coefficient decreased with increasing content of collagen and sulphated glycosaminoglycans. When grown as multicellular spheroids, no differences in either extracellular matrix composition or diffusion coefficient were found. Comparison of in vitro vs in vivo results suggests an over-riding role of host stromal cells in extracellular matrix production subjected to modulation by tumour cells. Penetration of therapeutic macromolecules through tumour extracellular matrix might thus be largely determined by the host organ. Hence, caution must be exercised in extrapolating drug penetrability from spheroids and multilayer cellular sandwiches consisting of only tumour cells to tumours in vivo.

Animals↗
PubMed1991

Microvascular phenomena during pancreatic islet graft rejection.

Transplantation of insulin secreting tissue as a free graft has the potential to become a safe and simple procedure to cure diabetes. However, clinical results, i.e. achievement of insulin independency, are poor, in spite of the use of immunosuppressive regimens, which are regularly successful in whole organ transplantation. In contrast to whole organ grafts, which are revascularized immediately after transplantation, free pancreatic islet grafts require the process of revascularization in order to establish a microvascular network, sufficient for the nutritional blood supply. We have demonstrated for the first time in vivo images of the process of revascularization of free islet xenografts including microvascular phenomena during graft rejection. Rat islet xenografts were isolated by collagenase digestion and transplanted into hamster dorsal skinfold chambers. After 6, 10 and 14 days the microvasculature of the islet grafts was analyzed by means of intravital fluorescence microscopy. Xenogeneic grafts were revascularized during the first 6 days similarly compared to syngeneic grafts; however, on day 10 after transplantation a reduction in size of the microvascular network as well as a decrease in functional capillary density and a reduction in capillary red blood cell velocity were observed, accompanied by microvascular rejection phenomena, such as an increase of microvascular permeability, edema formation, capillary widening and intravascular accumulation of white blood cells (WBCs) with concomitant WBC-endothelium interaction in post-capillary venules. Treatment with 2.5 mg/kg/d (+/-)-15-deoxyspergualin could not completely alleviate these microvascular rejection phenomena.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1983

In vivo mobilization of polymorphonuclear leukocytes in psoriasis: relationship to clinical parameters and serum inhibitory factors.

Mean migration of polymorphonuclear leukocytes (PMNL) toward autologous and homologous control sera, evaluated by quantitative skin window chamber technique, was only slightly reduced in 60 patients with psoriasis as compared to 27 normal controls (p less than 0.1). A significant decrease in cell migration was found (1) in patients with actively spreading lesions, (2) in patients with extensive lesions involving more than 40-60% of the skin surface, (3) in the first 2 months of relapse, and (4) 5-6 months after onset of new lesions. However, PMNL migration was increased when psoriatic lesions lasted 3-4 months. Seventy-one percent of psoriatic sera exerted a suppressive effect on the psoriatic and normal PMNL migration. The inhibitors were found predominantly in patients with stationary and long-standing lesions. Some of the psoriatic sera had a stimulatory effect on the chemotaxis of psoriatic PMNL. These sera originated from those patients with active spreading lesions in the first 2 months of relapse. These data indicate that neutrophil migration is abnormal in the course of psoriasis and that it could be modified by different proportions of both inhibitors and stimulators of chemotaxis.

Cell Movement↗
PubMed1978

In-vivo effects of anti-inflammatory and other drugs on granulocyte emigration in the rabbit skin collection chamber.

A method for measuring localised leukocyte mobilisation under in-vivo conditions with a plastic skin collection-chamber adapted to the rabbit ear was used for assessing the effects of anti-inflammatory and other agents on granulocyte emigration. Studies on the effect of oral drug administration to rabbits indicated that most anti-inflammatory drugs, two cystostatic agents (cyclophosphamide and colchicine), but none of the other compounds exhibiting antihistaminc, beta-adrenolytic or neuroleptic properties, significantly inhibited granulocyte mobilisation. The results after topical application of some of these agents into the chamber correlated well with those obtained after oral treatment. This technique may thus prove useful in selecting new compounds inhibiting granulocyte mobilisation in acute inflammatory reactions.

Animals↗
PubMed1980

Leucocyte mobilization to skin lesions.

Leucocyte mobilization to a chamber covering a skin lesion was studies in healthy volunteers. 111 Indium-labelled blood leucocytes accumulated in the chambers, indicating mobilization of leucocytes from the blood. The concentration of autologous serum in the chamber medium influenced the number of leucocytes mobilized, while heat inactivation of serum or the repeated use of the same serum had no effect on the counts. The use of zymosan-treated serum increased the mobilization by up to 53%. The kinetics for the mobilization of leucocytes to chambers containing autologous serum was followed in healthy subjects. The mobilization showed a uniform pattern, viz. a lag phase of 2--4 hours and maximal migration rates after 20--24 hours. The cumulated counts were 74 x 10(6) leucocytes/cm2/24 hours and 200 x 10(6) leucocytes/cm2/48 hours. Females and males exhibited the same kinetics and cumulated counts. Chamber leucocytes were predominantly neutrophil granulocytes (85--100%) with 2.9--3.6 nuclear segments. The chamber technique provides a simple method permitting quantitation of in vivo mobilization of leucocytes from the blood to an inflammatory lesion.

Blood↗
PubMed1971

A method for studying antibiotic concentrations in inflammatory exudate.

A new technique is described for studying antibiotic concentrations in an experimental inflammatory exudate in vivo. In most exudates concentrations of four antistaphylococcal drugs which were of potential therapeutic significance could be assayed, and fucidin appeared to diffuse best. Higher concentrations of all antibiotics gained access to the lesion in the first two hours of inflammation, suggesting that their mobility did not depend on binding to cells during the inflammatory response. The technique may ultimately help to elucidate the relationship between antibiotics and host defences at the primary sites of infection.

Adult↗
PubMed2002

Gene therapy for pancreatic cancer using an adenovirus vector encoding soluble flt-1 vascular endothelial growth factor receptor.

INTRODUCTION: Vascular endothelial growth factor (VEGF) plays an important role in tumor angiogenesis. The soluble form of flt-1 VEGF receptor inhibits VEGF activity in a dominant-negative manner. AIM: This study demonstrated the regional tumor suppression effect of adenovirus-mediated soluble flt-1 in human pancreatic cancer cells. METHODOLOGY: The VEGF expression level was examined in nine cell lines. Panc-1 and PK-8 were used as lower- and higher-VEGF-producing cell lines, respectively. The in vitro proliferation of cancer cells infected with adenovirus vectors encoding soluble flt-1 (Adsflt) and control vectors (AdLacZ) was not different. To assess the in vivo tumor growth suppression, cancer cells were inoculated subcutaneously in SCID mice. Adsflt, AdLacZ, or vehicle was injected directly into the tumors. The early process of tumor angiogenesis in a dorsal skinfold chamber was monitored by intravital microscopy. RESULTS: In both Panc-1 cells and PK-8 cells, the tumor growth of the Adsflt-treated group was significantly suppressed. The microvessel density, revealed by CD31 immunostaining, was also significantly lower in the Adsflt-treated group. Apoptosis index was higher in the Adsflt group. Immunofluorescence staining revealed the expression of VEGF not only in cancer cells but also in tumor stromal cells. Wild-type cells and AdLacZ-infected cells prompted strong tumor angiogenesis, whereas Adsflt-infected cells failed to exert such an effect. CONCLUSION: These results indicate that antiangiogenic gene therapy using soluble flt-1 might be an effective approach for pancreatic cancer treatment.

Adenoviridae↗
PubMed1996

Effect of recombinant granulocyte colony-stimulating factor on neutrophil kinetics in normal young and elderly humans.

Recombinant granulocyte colony-stimulating factor (G-CSF) was administered to healthy young (n = 32) and elderly (n = 19) volunteers (0 microgram/d, 30 microgram/d, or 300 microgram/d) to determine its effect on neutrophil production, blood kinetics, and tissue migration. Measurements included blood counts (daily), marrow neutrophil pool sizes and neutrophil tissue migration (baseline and day 5), blood kinetics (day 6), and marrow transit time while on drug (days 6 to 14). G-CSF markedly expanded the marrow neutrophil mitotic pool and shortened the transit time of the postmitotic pool (control, mean = 6.4 days; 300 microgram/d, mean = 2.9 d). G-CSF increased neutrophil production without significantly altering blood neutrophil half-life or margination. Compared to control, neutrophil accumulation in skin chambers decreased by about 50% in the 300 microgram/d group in both young and elderly subjects. G-CSF induced neutrophilia by stimulating proliferation of marrow neutrophil precursors and accelerating neutrophil entry into the blood. Decreased neutrophil inflammatory responses measured with the skin chamber technique may be because of the relative immaturity of the circulating cells or to alterations in neutrophil phenotype induced by G-CSF.

Adult↗
PubMed1986

[Importance of hyaluronic acid in the modulation of neutrophil migration].

The relationship between JA and phagocyte function has often been reported in the literature. The action of JA may either inhibit or stimulate PMNs function depending on the concentration. On the basis of this experience, the efficacy of JA action, both directly and mediated after incubation was studied. In particular phagocytosis, NBT, superoxide production and chemotaxis were studied in basal conditions and after incubation with hyaluronic acid. In particular chemotaxis was also performed to assay the chemotactic action of the medium in which the monocytes were incubated with JA and the technique was found to produce a distinct progressive improvement in the chemotactic index. In conclusion, it is hypothesised that monocytes incubated with JA produce a chemotactic factor for PMNs.

Adolescent↗