Laparoscopy improves outcomes for pediatric splenectomy

BACKGROUND: Pediatric laparoscopic splenectomy is a relatively new surgical procedure with a limited number of reports comparing its outcomes to that of the open procedure. The authors have minimized the invasiveness of our procedure by using only three ports and have described the technique as well as compared it with the open method. METHODS: A retrospective review of seven laparoscopic splenectomies (LS) using a three port technique were compared with seven open splenectomies (OS) performed for similar indications at a single children's hospital. RESULTS: The average age in the LS group was 8.7 years compared with 8.9 years for OS, (P value not significant), and the average weights were also similar. The indications for splenectomy were hereditary spherocytosis, idiopathic thrombocytopenic purpura, sickle cell anemia, and splenic cyst. All splenectomies were performed safely with an average estimated blood loss of 41 mL for LS and 34 mL for OS (P value not significant). Operative time averaged 147 minutes for LS and 86 minutes for OS (P < .05). LS patients recovered more rapidly and were discharged home on a median of postoperative day (POD) 2 versus POD 4 for OS (P < .05). LS patients received significantly less total amount of intravenous pain medication with an average of 0.18 mg/kg of morphine sulfate versus 0.8 mg/kg for OS (P< .05). Total hospital charges were higher for LS with an average of $10,899 versus $8,275 for OS (P < .05). CONCLUSIONS: Laparoscopic splenectomy currently is a safe procedure, offering better cosmesis, much less pain, and a shorter hospital stay compared with the traditional open procedure. The more sophisticated equipment and time needed to carry out the procedure led to a modestly increased hospital cost.     

Gliotoxin induces apoptosis in mouse L929 fibroblast cells

The effect of the fungal toxin gliotoxin on the adherence and viability of mouse L929 cultured cells was examined. Gliotoxin at concentrations below 2 microM had no effect on cell function. The initial effect of exposure (6 h) resulted in the loss of cell adherence, with the non-adhered cells retaining viability. However, prolonged exposure (24 h) did not significantly enhance gliotoxin's effect on cell adherence, though the majority of non-adhered cells were found to have died by apoptosis, as confirmed from (i) electron microscopic examination and (ii) agarose gel electrophoresis of isolated DNA. The addition of foetal bovine serum to the culture medium had no effect on gliotoxin's activity. Ethanol (gliotoxin's solvent) had no effect on the assayed cell functions suggesting that the observed effects are due to gliotoxin alone. These results demonstrate for the first time that gliotoxin can cause apoptosis in cells of non-haematopoietic origins.     

Characterization of [11C]tetrabenazine as an in vivo radioligand for the vesicular monoamine transporter

The erythrocytes of paroxysmal nocturnal hemoglobinuria are abnormally sensitive to complement-mediated lysis because they are deficient in membrane proteins that regulate the functional activity of complement. All the deficient proteins in paroxysmal nocturnal hemoglobinuria share the common structural feature of being anchored to the cell surface by a glycosyl phosphatidylinositol moiety. Recent studies showed that the first intermediate in the pathway of the glycosyl phosphatidylinositol anchor synthesis is not formed in paroxysmal nocturnal hemoglobinuria cells. This observation suggests that the molecular basis of paroxysmal nocturnal hemoglobinuria is due to an abnormality involving a gene that encodes a protein essential for the normal biosynthesis of the first intermediate. By using expression cloning, the complementary DNA (called phosphatidylinositol glycan class A [PIG-A]) that corrects the abnormality in glycosyl phosphatidylinositol-anchor synthesis in paroxysmal nocturnal hemoglobinuria cells was identified. Subsequent studies showed that the PIG-A gene is located on the X chromosome. Together, these studies provided a molecular explanation for paroxysmal nocturnal hemoglobinuria.     

Serum phospholipase A2 in patients after splenectomy

Phospholipase A2 values increase in serum in various inflammatory states, infections, and postoperatively in surgical patients. Several organs, including the liver and spleen have been suggested as sources of circulating phospholipase A2. The purpose of the present work was to examine the possible role of the spleen as a source of elevated serum concentrations of phospholipase A2 after surgery. Pre- and postoperative serum samples of patients undergoing splenectomy were studied for group I phospholipase A2, group II phospholipase A2, and C-reactive protein mass concentrations and catalytic activity concentration of phospholipase A2. The catalytic activity concentration of phospholipase A2 and the mass concentrations of group II phospholipase A2 and C-reactive protein increased postoperatively (8.08 +/- 1.40 U/l vs. 3.96 +/- 0.89 U/l (mean +/- SEM) for phospholipase A2 catalytic concentration (p < 0.03), and 154.8 +/- 32.1 micrograms/l vs. 47.5 +/- 14.7 micrograms/l (mean +/- SEM) for group II phospholipase A2 mass concentration (p < 0.02, n = 7). The mass concentration of group I phospholipase A2 remained unchanged. The catalytic concentration of phospholipase A2 correlated well with the mass concentration of group II phospholipase A2 (p < 0.001, r = 0.846, n = 43). The concentration of C-reactive protein correlated well with the mass concentration of group II phospholipase A2 (p < 0.001, r = 0.566, n = 43) in serum. The results indicate that group II phospholipase A2 is released into the circulation after splenectomy, and the spleen seems not to be the source of circulating group II phospholipase A2.     

Release and accumulation of neurotransmitters in the rat brain: acute effects of ethanol in vitro and effects of long-term voluntary ethanol intake

OBJECTIVE: The purpose of this study is to examine the accuracy and complications of transthoracic needle aspiration biopsy (TTNA) to determine its optimal role in the evaluation of patients with lung tumors. MATERIALS AND METHODS: The charts of 130 consecutive patients who had undergone CT-guided TTNA were reviewed retrospectively. Thirty-two (25%) of these patients had subsequent surgery and 5 had subsequent transbronchial biopsy (TBB). Using the final surgical and TBB diagnosis as a reference, the accuracy, sensitivity, specificity, and prevalence of malignancy were calculated. Each case was also examined to determine the presence or absence of complications. RESULTS: Of the 130 biopsy results, 95 (73%) were malignant, 33 (25%) were nonspecific, and only 2 (2%) had a specific benign diagnosis. Thirty-two patients subsequently underwent surgical resection. The overall prevalence of malignancy after surgical diagnosis was 91%. The overall diagnostic accuracy of TTNA was 76%. The sensitivity of TTNA for the detection of malignancy was 74% and its specificity was 100%. When comparing TTNA results of small (<3 cm) and large (> or = 3 cm) tumors, the occurrence of nonspecific results was 36% and 16%, respectively. Fifty-six (43%) patients had a pneumothorax subsequent to TTNA. Twenty-four (43%) of these patients required a chest tube and remained hospitalized for a mean of 6 days. CONCLUSION: Patients who are surgical candidates and have a high clinical suspicion for malignancy should undergo surgical biopsy and resection of their lung tumors if indicated. Information gained from TTNAs performed on this patient population will rarely result in a change in their clinical management.     

Limulus amebocyte lysate assay for detection of endotoxin in patients with sepsis syndrome. AMCC Sepsis Project Working Group

Clinical predictions alone are insufficiently accurate to identify patients with specific types of bloodstream infection; laboratory assays might improve such predictions. Therefore, we performed a prospective cohort study of 356 episodes of sepsis syndrome and did Limulus amebocyte lysate (LAL) assays for endotoxin. The main outcome measures were bacteremia and infection due to gram-negative organisms; other types of infection were secondary outcomes. Assays were defined as positive if the result was > or = 0.4 enzyme-linked immunosorbent assay units per milliliter. There were positive assays in 119 (33%) of 356 episodes. Assay positivity correlated with the presence of fungal bloodstream infection (P < .003) but correlated negatively with the presence of gram-negative organisms in the bloodstream (P = .04). A trend toward higher rates of mortality in the LAL assay-positive episodes was no longer present after adjusting for severity. Thus, results of LAL assay did not correlate with the presence of bacteremia due to gram-negative organisms or with mortality after adjusting for severity but did correlate with the presence of fungal bloodstream infection.     

Mice lacking dopamine D4 receptors are supersensitive to ethanol, cocaine, and methamphetamine

The human dopamine D4 receptor (D4R) has received considerable attention because of its high affinity for the atypical antipsychotic clozapine and the unusually polymorphic nature of its gene. To clarify the in vivo role of the D4R, we produced and analyzed mutant mice (D4R-/-) lacking this protein. Although less active in open field tests, D4R-/- mice outperformed wild-type mice on the rotarod and displayed locomotor supersensitivity to ethanol, cocaine, and methamphetamine. Biochemical analyses revealed that dopamine synthesis and its conversion to DOPAC were elevated in the dorsal striatum from D4R-/- mice. Based on these findings, we propose that the D4R modulates normal, coordinated and drug-stimulated motor behaviors as well as the activity of nigrostriatal dopamine neurons.     

Identification of a gene cluster of biosynthetic genes of rubradirin substructures in S. achromogenes var. rubradiris NRRL3061

Rubradirin, an ansamycin antibiotic has been purified from Streptomyces achromogenes var. rubradiris NRRL3061. It consists of four distinct structural moieties, rubransarol, 3-amino-4-hydroxy-coumarin, dihydroxydipicolinic acid, and 2,6-dideoxynitrosugar (DNS). Polymerase chain reaction (PCR) primers were designed based on consensus sequences of dTDP-D-glucose 4,6-dehydratase, one of enzymes involved in the biosynthesis of 2,6-dideoxysugar. A PCR product was obtained from S. achromogenes var. rubradiris. Hybridization of the PCR product to a cosmid library constructed from S. achromogenes genomic DNA has led to the identification of three unlinked regions of DNA. One of three kinds of cosmid clones contains homologues of dTDP-D-glucose 4,6-dehydratase, 3-amino-5-hydroxybenzoic acid (AHBA) synthase, and eryA genes. The size of the gene homologous to eryA is 30 kb, and the AHBA synthase gene homologue resides between the eryA homologous genes. A gene cluster of rubransarol and 2,6-dideoxynitrosugar is around 50 kb. Sequencing of the PCR product from the AHBA synthase gene homologue isolated from S. achromogenes revealed 85% amino acid sequence homology (73/86) with the AHBA synthase from a rifamycin-producer. dTDP-D-glucose 4,6-dehydratase gene homologue was subcloned from one of the isolated cosmid clones and sequenced. It showed 65% homology (43/66) with dTDP-D-glucose 4,6-dehydratase from a streptomycin-producer.     

Caspase-3-generated fragment of gelsolin: effector of morphological change in apoptosis

The caspase-3 (CPP32, apopain, YAMA) family of cysteinyl proteases has been implicated as key mediators of apoptosis in mammalian cells. Gelsolin was identified as a substrate for caspase-3 by screening the translation products of small complementary DNA pools for sensitivity to cleavage by caspase-3. Gelsolin was cleaved in vivo in a caspase-dependent manner in cells stimulated by Fas. Caspase-cleaved gelsolin severed actin filaments in vitro in a Ca2+-independent manner. Expression of the gelsolin cleavage product in multiple cell types caused the cells to round up, detach from the plate, and undergo nuclear fragmentation. Neutrophils isolated from mice lacking gelsolin had delayed onset of both blebbing and DNA fragmentation, following apoptosis induction, compared with wild-type neutrophils. Thus, cleaved gelsolin may be one physiological effector of morphologic change during apoptosis.