Intralipid对吞噬细胞氧自由基产生的影响

目的 观察Ｉｎｔｒａｌｉｐｉｄ对内毒素所致的多形核白细胞氧自由基产生的影响,方法 取２２例健康志愿者静脉血,采用Ｂｏｙｕｍ法提取多核白细胞（ＰＭＮ）并在体外培养,采用不同剂量的脂多糖（ＬＰＳ）刺激ＰＭＮ,并和不同剂量Ｉｎｔｒａｌｉｐｉｄ共同作用,采用ＮＢＴ还原剂试验测定氧自由基的产生量。结果 ＬＰＳ刺激各组的ＮＢＴ值明显高于非刺激组,而且ＮＢＴ值与ＬＰＳ浓度明显相关,Ｉｎｔｒａｌｉｐｉｄ可明显浓度     

Fungal prophylaxis by reduction of fungal colonization by oral administration of bovine anti-Candida antibodies in bone marrow transplant recipients

Candida overgrowth and invasion constitute a serious threat with a high mortality in BMT recipients. Currently available topical antifungal prophylaxis is largely ineffective, and as resistance to existing, absorbable drugs for systemic use is rapidly developing, new forms of therapy are needed. We investigated the effect of oral treatment of BMT recipients with a bovine immunoglobulin product derived from animals immunized against several Candida species. The natural Candida colonization was first followed in 19 patients to establish the colonization pattern. Half of the patients were found to be colonized prior to transplantation and altogether 72% were colonized at some point during follow-up. Those with a high pre-transplant concentration of Candida in saliva (>100 CFU/ml) remained colonized throughout the BMT treatment period. The therapeutic effect was monitored in two other patient groups. The first group consisted of nine patients, where, due to a low number of primary colonized patients, response in colonized patients was suggestive of a therapeutic effect. In the second group, 10 patients with a high level of colonization (>100 CFU/ml) were given 10 g daily of the product in three divided doses. The results suggest a treatment-related reduction in Candida colonization in a majority (7/10) of patients and one patient became completely negative. As no adverse effects were noted, our findings encourage additional studies in immunocompromised, transplant patients.     

Interaction between lung surfactant and nitric oxide production by alveolar macrophages stimulated by group B streptococci

The major etiologic agent in neonatal pneumonia and meningitis is group B streptococci (GBS). Nitric oxide (NO) production by alveolar macrophages (AM) in response to Gram-positive bacteria such as GBS and the effect of surfactant on this production have received little attention. We studied production of NO by GBS-stimulated AM using the Griess reaction, the effect of lung surfactant on this NO production, and the possible lipid peroxidation (LPO) of surfactant caused by NO. The LPO test was used to measure surfactant peroxidation. Heat-killed and live GBS were found to stimulate NO production by rat alveolar macrophages, and the presence of interferon gamma (IFN-gamma) increased this stimulation in a synergistic manner. Curosurf(R), the natural surfactant used in our study, significantly reduced NO production in various sets of experiments. Lipid peroxidation of surfactant was noted when NO was produced by stimulated AM, a phenomenon that could be suppressed by NG-monomethyl L-arginine (L-NMMA), the inhibitor of NO synthase. In the lung of GBS-infected neonates, nitric oxide produced by AM might contribute to the destruction of surfactant caused by inflammatory cells. Pediatr Pulmonol. 2000; 30:106- 113.     

Granulocytic function after administration of pepsin treated human gammaglobulin

Summary Pepsin-treated human gammaglobulin, 150 mg/kg body weight, was administered intravenously to 14 healthy volunteers. Before and after the infusion the nitroblue tetrazolium (NBT)-reduction of granulocytes was studied in all and the bactericidial capacity in 12 subjects. An increase of NBT reduction (p<0.05) and of bacterial capacity (p<0.01) of granulocytes was found after the infusion. The effects may be due to an opsonising action of F (ab)₂ components.

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Funktion der Granulozyten in Gegenwart von mit Pepsin behandeltem menschlichem Gammaglobulin

Zusammenfassung Pepsin behandeltes Gammaglobulin wurde 14 gesunden freiwilligen Versuchspersonen in Dosen von 150 mg/kg KG intravenös verabreicht. Vor und nach der Infusion wurde bei allen Probanden die Nitroblau-Tetrazolium-Reduktionsfähigkeit (NBT) der Granulozyten und bei 12 von ihnen die bakterizide Kapazität der Granulozyten bestimmt. Nach der Infusion war eine Erhöhung der NBT-Reduktionsfähigkeit der Granulozyten (p<0,05) und Verstärkung der Bakterizidie (p<0,01) nachweisbar. Möglicherweise beruht dieser Effekt auf einer opsonierenden Wirkung von F (ab)₂ Komponenten.

     

Functions of human neutrophilic granulocytes after in vivo exposure to interferon alpha.

The ability of neutrophilic granulocytes to phagocytize yeast particles and to reduce Nitro Blue Tetrazolium at rest and on activation with bacterial stimuli was monitored in 32 patients receiving treatment with human interferon alpha. The ability of these cells to attach to and ingest yeast particles was not altered to any major extent during 1 year of interferon treatment. In most patients, the Nitro Blue Tetrazolium-reducing activity increased after the first injection of interferon. During prolonged treatment with interferon alpha, 1 week to 1 year, granulocytes activated with bacteria exhibited a reduced Nitro Blue Tetrazolium activity in most patients.     

Effect of radiation therapy and in vitro x-ray exposure on lymphocyte subpopulations and their functions

Radiation treatment of breast cancer patients (45.0 Gy) profoundly affected the peripheral blood lymphocytes. The number of these cells was markedly reduced with non-T-cells being more extensively depleted than T-cells immediately after radiation. The long-lasting lymphopenia, on the other hand, was mainly due to reduced number of T-cells. Antigen and mitogen stimulability, MLC reactivity, pokeweed (PWM)-induced immunoglobulin (Ig) production in vitro, and different cytotoxic functions decreased. Depletion of lymphocytes largely restored the radiation-depressed lymphocyte reactivity. The effects of in vitro exposure of blood lymphocytes to x-rays were similar to those seen after radiotherapy. Non-T-cells and T-cells with Fc-receptors for IgG were relatively radiosensitive. This latter observation agreed well with demonstrated increase of PWM-induced Ig synthesis after in vitro exposure to x-rays. T-suppressor cells defined by monoclonal antibodies were, however, radioresistant. The cytotoxic functions were reduced. No correlations were found between the pretreatment immunological status or the extent of radiation-induced immunological suppression, respectively, and prognosis.     

Neutrophil leucocyte function in primary hyperparathyroidism

Neutrophil leucocyte chemotaxis, phagocytosis and oxidative metabolism were measured in six patients with primary hyperparathyroidism (HPT) who underwent parathyroidectomy. The preoperative neutrophil chemotaxis value was 6.2 +/- 0.3 arb.U. and this decreased to 5.8 +/- 0.5 arb.U. (p less than 0.05) on the third postoperative day and to 5.4 +/- 0.3 arb.U. three weeks later. Serum calcium levels were 2.95 +/- 0.06 mmol/l preoperatively and decreased to 2.20 +/- 0.05 (p less than 0.05) and 2.34 +/- 0.05 mmol/l (p less than 0.05) on the third and 21st day after parathyroidectomy. Phagocytosis measured as the intracellular uptake of complement-opsonized yeast particles by neutrophils was not influenced by operation. In a control group, six patients undergoing hemithyroid ectomy due to microfollicular tumours were studied. In this group leucocyte chemotaxis, phagocytosis and serum calcium levels were not significantly different before and after surgery. Neutrophil oxidative metabolism, measured by the ability of the cells to reduce nitroblue tetrazolium (NBT), was similar in the HPT and control groups both before and after operation. The results indicate that HPT is associated with an abnormal leucocyte migration which is reversed after successful parathyroidectomy.     

Plasma fibronectin is initially decreased during septicemia

Plasma fibronectin (PFN) levels were measured by radioimmunoassay in 24 normals and serially in 24 septic patients without underlying major trauma. All patients responded promptly to antibiotic therapy and none developed signs of shock or disseminated intravascular coagulation (DIC). After an initial decrease in PFN registered in most of the septic patients, the levels were normalized within 2 weeks of antibiotic treatment. The mean nadir levels of PFN were decreased (p less than 0.001) both in patients with gram-negative and gram-positive etiologies compared to the control group. Furthermore, the mean PFN value of the gram-positive group was lower (p less than 0.05) than that of the gram-negative group. It is concluded that a transient depletion of PFN is a constant finding in septic patients with a favourable outcome and that a single low PFN level alone does not justify fibronectin replacement therapy nor does it indicate a poor prognosis.     

Direct and Phagocyte-mediated Lipid Peroxidation of Lung Surfactant by Group B Streptococci

In newborn infants, group B streptococci (GBS) often cause pneumonia, with polymorphonuclear leukocytes (PMN) migrating into the lungs. Because surfactant therapy may be needed in such patients, we evaluated the interaction between GBS or GBS-stimulated PMN and a surfactant preparation (Curosurf) in vitro. The superoxide production of GBS strains or GBS-activated PMN was measured, using the nitroblue tetrazolium (NBT) test and the subsequent lipid peroxidation (LPO) as the content of malondialdehyde (MDA) and 4-hydroxyalkenals (4-HNE). The growth of GBS in surfactant was determined and related to the LPO. Finally, the effect of LPO on surfactant activity, caused by GBS-stimulated PMN, was assessed by measuring dynamic surface tension in a pulsating bubble surfactometer. Curosurf diminished the NBT reduction by both live GBS and GBS-stimulated PMN. Surfactant was peroxidized by reactive oxygen species (ROS) from both GBS and GBS-stimulated PMN in a time-dependent manner. Vitamin E significantly reduced the peroxidation level of surfactant in both cases. Surfactant peroxidation was associated with a reduction in the number of live bacteria. The biophysical activity of Curosurf was impaired by GBS-stimulated PMN, as reflected by increased minimum surface tension during cyclic compression. These findings indicate that Curosurf undergoes LPO by ROS produced by GBS and/or PMN. We speculate that exogenous surfactant preparations should be supplemented with vitamin E or another antioxidant, when given to infants with GBS pneumonia. Accepted for publication: 21 August 2000     

Serum triglyceride elevations in patients with septicemia

Among 239 patients with septicemia or endocarditis 41 (17%) had serum triglyceride levels in excess of 2.2 mmol/l (mean 3.1 mmol/l). This was more common in infectious with gram-negative rods than gram-positive cocci (p less than 0.001). A return to normal levels occurred in 22/37 patients during the course of the infection.