术前预防性使用抗生素对剖宫产切口感染的影响

目的探讨术前预防性使用抗生素对剖宫产术后切口感染的影响。方法以2012年1月至2014年1月间我院收治的106例剖宫产孕妇为研究对象,随机分为术前应用抗生素组(观察组)及术后应用抗生素组(对照组)各53例。比较两组患者术中出血量、术后体温及血液学检查结果,观察患者术后感染情况。结果观察组术中出血量为165.4 mL,对照组为159.2 mL,两组之间差异无统计学意义(P>0.05);观察组甲级愈合率为96.2%,对照组甲级愈合率为90.6%,两组之间差异有统计学意义(P<0.05);观察组术后最高体温>38℃者4例、对照组术后最高体温>38℃者7例,两组之间差异无统计学意义(P>0.05);观察组C反应蛋白异常升高者2例,对照组术后C反应蛋白异常升高者9例,两组之间差异有统计学意义(P<0.05);观察组术后腹部切口感染、产褥感染例数分别为1例和1例,对照组术后腹部切口感染、产褥感染例数分别为5例和3例,两组之间差异有统计学意义(P<0.05);两组术后各有1例泌尿系统感染病例,差异无统计学意义(P>0.05)。结论术前预防性使用抗生素降低患者术后切口感染的发生,有利于切口愈合。     

Evaluation of KIR ligand incompatibility in mismatched unrelated donor hematopoietic transplants. Killer immunoglobulin-like receptor

One of the functions of HLA class I alleles is interaction with natural killer (NK) cells. Receptors termed killer immunoglobulin-like receptors (KIRs) on NK cells recognize groups of HLA class I alleles, and interaction between receptor and class I allele inhibits reactivity of the NK cell. Failure to recognize the appropriate KIR ligand on a mismatched cell can trigger NK cell elimination of that target cell. Recent analysis of haploidentical hematopoietic transplantations has shown a reduction of graft failure, graft-versus-host disease, and relapse in those with KIR ligand incompatibility in the graft-versus-host direction. In this study we analyzed the effect of KIR ligand incompatibility on outcomes of unrelated donor bone marrow transplantations. The data show no advantage for KIR ligand incompatibility in this clinical setting as assessed by HLA-Bw4 and HLA-C alleles. It is possible that there will be a benefit of NK cell alloreactivity if strategies of haploidentical transplantation are used: high stem cell doses, extensive T-cell depletion, and no postgrafting immune suppression.     

Prenatal diagnosis of beta-thalassemias by amniocentesis: linkage analysis using multiple polymorphic restriction endonuclease sites

In order to assess the applicability of multiple restriction endonuclease analyses of amniocyte DNA to the prenatal diagnosis of beta-thalassemias in general, we studied 12 consecutive couples at risk. DNA of both members of the 12 couples and a previous offspring of each was analyzed for the presence of 4 polymorphic restriction endonuclease sites: the Hpa I site 3' to the beta-globin gene, the Hind III site in the G gamma gene, the Hind III site in the A gamma gene, and the Bam HI site 3' to the beta-gene. Linkage disequilibrium between these sites and beta A or beta thal genes was not found, presumably due to the heterogeneity of beta thal genes. However, the high frequency of polymorphism at these sites allowed differentiation of beta A-bearing chromosomes from beta thal or beta S-bearing chromosomes in both members of 6 couples. In these couples, complete prenatal diagnosis by linkage analysis of amniocyte DNA would be possible. In the remaining 6 couples, beta A and beta thal chromosomes could be discriminated in one member. In about 50% of the pregnancies of these couples, exclusion of beta-thalassemia is possible by this analysis. These data suggest that when linkage analysis of polymorphic restriction endonuclease sites is carried out, prenatal diagnosis of beta-thalassemia states can be accomplished by amniocentesis alone in 75% of pregnancies at risk.     

Effect of cell concentration on bone marrow and peripheral blood stem cell cryopreservation

The effects of cell concentration during cryopreservation on bone marrow (BM) or peripheral blood (PB)-derived hematopoietic progenitor cells have not been described. The much greater numbers of cells harvested for autologous PB stem cell (PBSC) transplantation requires that the cells be frozen at higher cell concentrations, or in much greater volumes, compared with BM. We cryopreserved 108 PBSC collections from 30 patients at an average (+/- SD) cell concentration of 3.7 +/- 1.9 x 10(8) nucleated cells per mL in 127 +/- 45 mL. The proportion of mononuclear cells was 52.9% +/- 27.2%. The products also contained 2.9 +/- 2.1 x 10(9) platelets/mL and an average red cell proportion of 12.9% +/- 7.2%. The nucleated cell recovery after thawing was 75.4% +/- 13.0%. The nucleated cell concentration during freezing was not predictive for the postthaw recoveries of nucleated cells (P = .38), granulocyte-macrophage colony-forming unit (P = .06) or CD34+ cells (P = .54), or for the viability of mononuclear cells (P = .81). The platelet and red cell concentrations similarly were not predictive for these endpoints. Samples (3 BM, 7 PBSC) from 10 patients were simultaneously cryopreserved at two-fold, and from 5 additional patients (PBSC) at 6- to 24-fold differing cell concentrations. A lower recovery of erythroid burst forming unit was found for samples frozen at higher cell concentrations (P = .04), but no significant differences were found in the other endpoints listed above. The average cell concentration during freezing for each patient's PBSC collections (n = 34 patients) did not predict time to achieve a PB count of > 500 granulocytes/microL (P = .51) or platelet transfusion independence (P = .39). Patients achieved these endpoints of engraftment at medians of 12 and 13 days, respectively. The infusion of these products was generally well tolerated. Similarly, the cell concentration at which BM cells were frozen did not predict for the duration of granulocyte (P = .63) or platelet (P = .36) aplasias for 54 patients undergoing autologous BM transplantation. These data suggest that PBSC or BM cells collected for transplantation may be cryopreserved at very high cell concentrations without loss of engraftment potential or undue infusion-related toxicity.     

Lactoferrin biosynthesis during granulocytopoiesis

We examined the synthesis of lactoferrin, an iron binding protein that, among hematopoietic cells, is restricted to secondary granules of polymorphonuclear leukocytes. Lactoferrin biosynthesis was absent from leukemic myeloblasts and promyelocytes but abundant in normal bone marrow and both the bone marrow and peripheral blood of patients with chronic myelogenous leukemia (CGL) if the samples contained substantial numbers of myelocytes and metamyelocytes. Lactoferrin was present in the steady state in normal or CGL bands and polymorphonuclear leukocytes, but no lactoferrin biosynthesis was detectable in these samples. Taken together, these results suggest that lactoferrin accumulation begins with the onset of biosynthesis at the myelocyte stage and is largely complete by the beginning of the band stage of maturation. HL-60 cells, a permanent promyelocytic leukemia cell line, synthesized no lactoferrin. Translation of messenger RNA in Xenopus laevis oocytes revealed that mRNA from patients with chronic myelogenous leukemia and abundant myelocytes and metamyelocytes directed the synthesis of readily detectable amounts of lactoferrin, whereas HL-60 cells contained no translatable lactoferrin mRNA. We thus hypothesize that lactoferrin is a useful marker of gene expression restricted to the terminal stages of granulocyte maturation. Biosynthesis of this protein appears to be mediated by appearance of translatable mRNA at the myelocyte stage, coincident with development of secondary granules. Absence of lactoferrin production by HL-60 cells is due to absence of translatable lactoferrin mRNA, either because of lineage infidelity of these transformed cells or because of arrest before the developmental stage at which secondary granules appear.     

Decreased inducible expression of CD80 and CD86 in human monocytes after ultraviolet-B irradiation: its involvement in inactivation of allogenecity

Ultraviolet-B (UV-B) irradiation of antigen presenting cells (APCs) modifies their allogenecity, resulting in inhibition of the proliferative response of T cells in mixed lymphocyte reaction (MLR). Costimulation by the CD28 ligand CD80 (B7/B7-1) and CD86 (B70/B7-2) plays an important role during T-cell proliferation by augmenting synthesis of interleukin-2 (IL-2) and other cytokines. In this study, we demonstrated induced expression of both CD80 and CD86 during allogeneic MLR, though human freshly isolated monocytes express CD86 constitutively with a much lower level of CD80. A monoclonal antibody (MoAb) against CD86, but not CD80, efficiently inhibited allogeneic T- cell proliferative responses stimulated with highly purified monocytes. UV-B exposure (0 to 1,000 J/m2) of monocytes inhibited the proliferation of T lymphocytes in MLR in a dose-dependent manner. Flow cytometric analysis showed that UV-B exposure of monocytes impaired the constitutive expression of CD54 (intercellular adhesion molecule-1) by 24 hours after irradiation, but the effect on CD86 was relatively less. The surface expression of CD80, CD86, CD54, and HLA-DR on monocytes was further augmented by interferon (IFN)-gamma; this cytokine-induced expression was dose-dependently reduced by UV-B irradiation. Similarly, the upregulation of these molecules following allogeneic MLR was downregulated by UV-B irradiation. UV-B irradiation of monocytes inhibited the expression of IL-2 mRNA in monocyte-stimulated allogeneic MLR. In contrast, the addition of anti-CD28 MoAb at the onset of MLR prevented, at least partially, the reduction of IL-2 mRNA. These results strongly suggest that the impairment of inducible expression of CD86 and CD80 may contribute to the reduced MLR response following exposure of monocytes of UV-B.     

Acute appendicitis in the setting of Clostridium difficile colitis: case report and review of the literature

A 72-year-old man was hospitalized for exacerbation of chronic obstructive pulmonary disease and was treated with oral prednisone and 7 days of moxifloxacin. Five days after completing the antibiotic course, he developed watery diarrhea and diffuse, crampy abdominal pain. On presentation he was afebrile, and abdominal examination revealed diffuse tenderness without peritoneal signs. Stool tested positive for Clostridium difficile toxin A by enzyme-linked immunosorbent assay. Despite starting oral metronidazole, the patient developed a fever of 101.2 degrees F 36 hours after his initial episode of diarrhea, 12 hours after admission. His abdominal pain intensified and became localized to the right and left lower quadrants. Computed tomography scan revealed both a thickened cecal wall and an edematous appendix with ileocecal stranding consistent with appendicitis. Appendectomy was performed, and the appendix was found to be suppurative in appearance and nonperforated. The cecum had mild edema and erythema, whereas the colon and rectum were grossly unaffected. Pathology examination revealed exudative material in the appendiceal lumen and a diffuse transmural inflammatory cell infiltrate. The patient had an uneventful recovery and continued to improve on oral metronidazole. Although Clostridium difficile colitis and appendicitis are each very common independently, C. difficile as an etiology of appendicitis is exceedingly rare. A review of the literature revealed 2 prior cases. We speculate that this association is underdiagnosed, because milder cases might respond to antibiotic therapy alone, and severe cases might involve the entire colon and require total colectomy. In each scenario, the involvement of the appendix might be overlooked.     

The effect of recombinant GM-CSF on the recovery of monkeys transplanted with autologous bone marrow

The regulatory function of recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) on granulocyte production in vivo was evaluated in an autologous bone marrow transplantation model using rhesus monkeys. Monkeys were exposed to 9.0 Gy total body irradiation and then transplanted with 5.0 x 10(7) low-density bone marrow cells/kg. Alzet miniosmotic pumps were subcutaneously implanted to deliver rhGM-CSF at a rate of 50,400 U/kg/d. Minipumps, containing either rhGM-CSF or saline, were implanted between zero and five days after transplantation for seven days. Kinetic recoveries of peripheral blood cells after either saline or rhGM-CSF treatment were compared. Treatment with rhGM-CSF accelerated the recovery of neutrophils. Neutrophils in rhGM-CSF-treated animals recovered to 80% (3.4 x 10(3)/mm3) pre-irradiation control levels by day 20, in comparison with only 33% (0.9 x 10(3)/mm3) recovery for saline control monkeys. In addition, the recovery of neutrophils was enhanced over that of the controls, reaching 140% v 70% on day 30. Another prominent feature of rhGM-CSF-treated monkeys was the accelerated recovery of platelets, reaching near 50% normal levels by day 24 in comparison with 20% of normal levels for controls. The infusion of rhGM-CSF was shown to be an effective regulator of early hematopoietic regeneration, leading to the accelerated recovery of both neutrophils and platelets and then providing a consistent sustained increase of neutrophils even in the absence of rhGM-CSF.