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An insufficient future liver remnant(FLR)is associated with post-hepatectomy liver failure.Associating liver partition and portal vein ligation for stage hepatectomy(ALPPS)has been shown to be effective for the induction of rapid FLR hypertrophy so as to improve the resectability in patients with insufficient FLR.We hereby report our experience of this novel approach for a 6-year-old patient with hepatoblastoma.Computed tomography showed a hepatoblastoma measuring12.5 cm×9.9 cm×11.7 cm in the right liver(Couinaud segmentⅣ,ⅤandⅧ).Volumetric assessment of the FLR i.e.,left lateral section was 112.6 mL i.e.,21.2%of the estimated total liver volume.In view of the small-for-size FLR,ALPPS was contemplated.An anterior approach was adopted for the in-situ parenchymal split without mobilisation of the right liver.FLR volumetry on the seventh postoperative day was 160.7 mL,which represented a 46.1%gain in volume,and a FLR/ESLV ratio of 30.2%.A right trisectionectomy was performed on the eighth postoperative day.Postoperative recovery was uneventful.Patient was discharged on day 16 after the first operation.To our knowledge,this was the first report that showed the applicability of ALPPS to a paediatric patient.  相似文献   
13.
Hemorrhagic tumor necrosis is an inflammatory event that leads to selective destruction of malignant tissues, with both potentially toxic and beneficial consequences. A pilot clinical trial was undertaken combining tumor necrosis factor-alpha (TNF-alpha) with the monoclonal antibody R24 (MoAb R24) against GD3 ganglioside in patients with metastatic melanoma. Patients received MoAb R24 to recruit leukocytes to the tumor followed by low doses of recombinant TNF-alpha to activate leukocytes. Eight patients were treated and seven patients had mild toxicity. One patient with extensive metastatic melanoma developed tumor lysis syndrome within hours after treatment with almost complete necrosis of bulky tumors in multiple visceral sites. To our knowledge, this is the first documented case of hemorrhagic tumor necrosis in a patient with metastatic cancer in multiple visceral sites.  相似文献   
14.
Klock  JC; Boyles  J; Bainton  DF; Stossel  TP 《Blood》1979,54(6):1216-1229
We have investigated the effects of mechanical elution of neutrophils from nylon-wool fiber (NWF) using the scanning electron microscope and biochemical analysis of elution fractions. We have determined that mechanical removal of neutrophils from nylon-wool fiber disrupts neutrophils adherent to nylon-wool fiber and augments release of granules, release of peripheral cytoplasmic fragments, and release of lactic dehydrogenase, a soluble cytoplasmic enzyme. Mechanical shearing of the adherent cell, and not adherence per se, causes the fragmentation. The extent of fragmentation is proportional to the NWF surface area available to neutrophils and is maximal at the temperature for optimal adherence and spreading. Agents that decrease cell spreading (n-ethylmaleimide and cold) diminish fragmentation. Cytochalasin B, an agent that destabilizes the neutrophil cortex, increases fragmentation. Fragmentation may be an important contributing cause of the abnormal morphology, function, and in vivo survival of nylon-wool-fiber procured human neutrophils. The prevention of fragmentation would appear to be necessary to insure the procurement of optimally functioning cells. Elution of NWF-adherent neutrophils in the cold might be a practical way to diminish neutrophil damage during clinical filtration leukapheresis.  相似文献   
15.
Polymorphonuclear leukocytes (PMN) with a deficiency of the complement receptor type 3 (CR3) membrane glycoprotein family have impairments in the ability to adhere to surfaces as well as chemotactic and phagocytic defects, processes that require a functional contractile apparatus. PMN from the patient with neutrophil actin dysfunction (NAD) displayed similar functional characteristics to those with CR3 deficiency suggesting the two disorders may be the same disease. In order to evaluate the relationship between CR3 deficiency and actin assembly, actin filament assembly was measured in PMN from six previously reported homozygotes (two severe and four moderate CR3-deficient patients) as well as five heterozygotes for CR3 deficiency. PMN from all patients had normal unstimulated concentrations of F-actin and after exposure to the chemotactic peptide FMLP (5 x 10(-7) mol/L for 5 to 40 seconds at 25 degrees C) assembled actin normally. Pretreatment of normal PMN with concentrations of monoclonal anti-alpha CR3 antibody, capable of blocking PMN adherence, also failed to impair FMLP- induced actin filament assembly. CR3 glycoprotein expression was measured in PMNs from the mother, father, and older sister of the NAD patient (N Engl J Med 291:1093, 1974). Actin filament assembly was recently shown to be defective in PMNs from all three family members. The total concentrations of the alpha and beta CR3 subunits were below normal in PMN detergent extracts from the mother (25% of simultaneous controls) and older sister (56% of control). PMN surface expression of these two subunits was also found to be depressed (mother, 50%; older sister, 63% of control). These findings suggest these two NAD family members are heterozygote carriers for CR3 deficiency as well as NAD. Simultaneous studies of the father, however, demonstrated normal total concentrations of both the alpha and beta CR3 subunits (126% of controls) as well as normal surface expression of both subunits after phorbol myristate acetate stimulation and incubation at 37 degrees C (mean, 112% of controls) but slightly lower than normal levels after FMLP stimulation (mean, 83%). These findings indicate that CR3 deficiency generally is not associated with defective actin filament assembly and support the conclusion that NAD represents a unique kindred in which PMN actin function differs from previously reported genotypes of CR3 deficiency.  相似文献   
16.
Amrein  PC; Stossel  TP 《Blood》1980,56(3):442-447
Proteases can complicate the characterization of proteins from cells, especially human polymorphonuclear leukocytes (PMN), which contain abundant neutral proteases. We tested the ability of agents to inhibit proteolysis, with special reference to the subunit polypeptides of the contractile proteins actin, myosin, and actin-binding protein (ABP). Phenylmethylsulfonyl fluoride (PMSF), O-phenanthroline, EGTA, EDTA, N- ethylmaleimide, alone or in combinations, failed to prevent extensive proteolysis of the PMN proteins during solubilization of cells with dodecyl sulfate. These inhibitors and also alpha-1-antitrypsin and soybean trypsin inhibitor similarly could not prevent proteolysis during homogenization of cells in cold isosomolar sucrose. Treatment of PMN with greater than or equal to mM diisopropylfluorophosphate (DFP) prior to solubilization or homogenization markedly inhibited proteolysis. PMSF and DFP were equally effective in inhibiting proteolysis in PMN extracts, suggesting that the efficacy of DFP may result from its permeation of intact cells and granules before barriers are disrupted by detergents or homogenization. Treatment of PMN with DFP under conditions inhibiting proteolysis did not affect their rate of phagocytosis. We recommend the use of DFP in future studies correlating functions and protein structure of PMN.  相似文献   
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Loughran  TP Jr 《Blood》1993,82(1):1-14
Three distinct clinical syndromes occur in patients with increased numbers of circulating LGL. Patients with T-LGL leukemia have clonal proliferations of CD3+ LGL typically associated with chronic neutropenia and autoimmune features. NK-LGL leukemia is characterized by clonal CD3- LGL proliferation with an acute clinical presentation marked by massive hepatosplenomegaly and systemic illness. However, most patients with increased numbers of CD3- LGL do not have clinical features of NK-LGL leukemia and have a chronic clinical course. X- linked gene analyses have supported a polyclonal LGL lymphocytosis in this syndrome. Further studies are needed to determine whether clonal progression can occur in these patients.  相似文献   
20.
Saposins are small, heat-stable glycoproteins required for the hydrolysis of sphingolipids by specific lysosomal hydrolases. Saposins A, B, C, and D are derived by proteolytic processing from a single precursor protein named prosaposin. Saposin B, previously known as SAP-1 and sulfatide activator, stimulates the hydrolysis of a wide variety of substrates including cerebroside sulfate, GM1 ganglioside, and globotriaosylceramide by arylsulfatase A, acid beta-galactosidase, and alpha-galactosidase, respectively. Human saposin B deficiency, transmitted as an autosomal recessive trait, results in tissue accumulation of cerebroside sulfate and a clinical picture resembling metachromatic leukodystrophy (activator-deficient metachromatic leukodystrophy). We have examined transformed lymphoblasts from the initially reported saposin B-deficient patient and found normal amounts of saposins A, C, and D. After preparing first-strand cDNA from lymphoblast total RNA, we used the polymerase chain reaction to amplify the prosaposin cDNA. The patient's mRNA differed from the normal sequence by only one C----T transition in the 23rd codon of saposin B, resulting in a threonine to isoleucine amino acid substitution. An affected male sibling has the same mutation as the proband and their heterozygous mother carries both the normal and mutant sequences, providing additional evidence that this base change is the disease-causing mutation. This base change results in the replacement of a polar amino acid (threonine) with a nonpolar amino acid (isoleucine) and, more importantly, eliminates the glycosylation signal in this activator protein. One explanation for the deficiency of saposin B in this disease is that the mutation may increase the degradation of saposin B by exposing a potential proteolytic cleavage site (arginine) two amino acids to the amino-terminal side of the glycosylation site when the carbohydrate side chain is absent.  相似文献   
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