RESUMO
Improved understanding of risk factors associated with carbapenem-resistant-Klebsiella pneumoniae (CR-KP) infection after liver transplantation (LT) can aid development of effective preventive strategies. We performed a prospective cohort study of all adult patients undergoing LT at our hospital during 30-month period to define risk factors associated with CR-KP infection. All patients were screened for CR-KP carriage by rectal swabs before and after LT. No therapy was administered to decolonize or treat asymptomatic CR-KP carriers. All patients were monitored up to 180 days after LT. Of 237 transplant patients screened, 41 were identified as CR-KP carriers (11 at LT, 30 after LT), and 20 developed CR-KP infection (18 bloodstream-infection, 2 pneumonia) a median of 41.5 days after LT. CR-KP infection rates among patients non-colonized, colonized at LT, and colonized after LT were 2%, 18.2% and 46.7% (p < 0.001). Independent risk factors for CR-KP infection identified by multivariate analysis, included: renal-replacement-therapy; mechanical ventilation > 48 h; HCV recurrence, and colonization at any time with CR-KP. Based on these four variables, we developed a risk score that effectively discriminated patients at low versus higher risk for CR-KP infection (AUC 0.93, 95% CI 0.86-1.00, p < 0.001). Our results may help to design preventive strategies for LT recipients in CR-KP endemic areas.
Assuntos
Carbapenêmicos/uso terapêutico , Portador Sadio/microbiologia , Farmacorresistência Bacteriana , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/isolamento & purificação , Transplante de Fígado , Adulto , Idoso , Estudos de Coortes , Contagem de Colônia Microbiana , Feminino , Humanos , Incidência , Infecções por Klebsiella/diagnóstico , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Modelos Estatísticos , Análise Multivariada , Estudos Prospectivos , Fatores de Risco , Fatores de TempoRESUMO
The pear psylla, Cacopsylla pyri L. (Hemiptera: Psyllidae), is a relevant pest of pear, Pyrus communis L., trees in Emilia-Romagna region (northern Italy). The susceptibility to the insecticide abamectin was evaluated at different times of the year on C. pyri populations undergoing different control strategies within conventional, integrated, and organic farms. The tests performed were the egg spray and the topic and dip bioassay on adults. The larval mortality was evaluated by dip bioassay on treated leaves. The activity of P450-dependent monooxygenases, a relevant enzyme system involved in insecticide resistance of C. pyri, was also determined in adults by 7-ethoxycoumarin O-deethylation (ECOD assay). Tests on treated eggs and on larvae showed no significant differences in LC50 and LC90, although these values were always lower in individuals collected from organic farms in comparison with all other farms. Tests on overwintering adults revealed differences among populations, probably more related to collection time than to field pest control strategies. Unexpectedly, the ECOD assay on adults showed a slightly higher cytochrome P450 monooxygenase activity in the population undergoing organic control in comparison to others. Our results indicate that egg spray is the most reliable bioassay to verify data of open-field applications. Apparently, no resistance to abamectin has yet been developed by C. pyri in Emilia-Romagna.
Assuntos
Hemípteros , Inseticidas , Ivermectina/análogos & derivados , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Hemípteros/enzimologia , Itália , Larva , Dose Letal Mediana , Óvulo , PyrusRESUMO
The mechanisms by which ethanol administration alters pancreatic function are unknown. We have evaluated the effects of chronic ethanol treatment on secretion of a digestive enzyme: the bile salt-dependent lipase (BSDL), by the rat pancreatic cell line AR4-2J (as a model). We report that ethanol (50-300 mM) in culture medium induced a rise, in secreted and intracellular BSDL, that was a function of the duration of treatment and of the ethanol concentration. This effect was not abolished by pyrazole, which suggests a direct effect of ethanol. We have further established that the increase of BSDL activity was due to an enhanced biosynthesis of the enzyme consecutive to a major steady-state level of mRNA encoding BSDL. Also, the subcellular localization showed a specific accumulation of BSDL in the cytosolic fraction of cells chronically treated with ethanol. Given the enzymatic properties of BSDL, all these data could have some physiological consequences regarding the digestive function, plasma lipid metabolism and intracellular cholesterol homeostasis.
Assuntos
Etanol/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Esterol Esterase/genética , Animais , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Pâncreas/enzimologia , Neoplasias Pancreáticas , Pirazóis/farmacologia , RNA Mensageiro/metabolismo , Ratos , Esterol Esterase/biossíntese , Transcrição Gênica/efeitos dos fármacos , Células Tumorais CultivadasRESUMO
OBJECTIVE: To measure plasma malondialdehyde (MDA) concentration, a product of lipid peroxidation, both in IDDM patients and in healthy control subjects and to examine whether smoking has a negative impact on the plasma MDA levels in diabetic patients. RESEARCH DESIGN AND METHODS: Plasma total MDA concentration (as a thiobarbituric acid adduct by high-performance liquid chromatography) was measured in 56 young IDDM patients and in a group of 32 age-, sex-, BMI-, and smoking habit-matched healthy subjects. RESULTS: Plasma MDA concentration in IDDM patients was significantly higher than that in healthy control subjects (mean +/- SE: 0.95 +/- 0.03 vs. 0.54 +/- 0.03 mumol/l; P < 0.0001). After stratification by smoking status, it was seen that diabetic smokers had values of age, BMI, serum lipids, blood pressure, metabolic control, and diabetes duration and its chronic complications superimposable on those of their nonsmoking counterparts. Nevertheless, plasma MDA concentration was significantly higher in IDDM patients who smoked than in IDDM patients who didn't smoke (1.03 +/- 0.4 vs. 0.87 +/- 0.03 mumol/l; P = 0.002), without any sex difference with regard to MDA levels. CONCLUSIONS: These data show an increase in circulating products of lipid peroxidation in young diabetic smokers, thus further supporting the clinical importance of discouraging the initiation of smoking as well as promoting its cessation in people with IDDM.
Assuntos
Diabetes Mellitus Tipo 1/sangue , Peroxidação de Lipídeos , Peróxidos Lipídicos/sangue , Fumar/sangue , Adulto , Glicemia/análise , Pressão Sanguínea , Colesterol/sangue , HDL-Colesterol/sangue , Feminino , Frutosamina/sangue , Hemoglobinas Glicadas/análise , Humanos , Masculino , Malondialdeído/sangue , Valores de Referência , Triglicerídeos/sangueRESUMO
Bile salt-dependent lipase (BSDL), an enzyme normally found in human pancreatic secretions is a 100 kDa glycoprotein. A BSDL-specific 477 bp cDNA probe was prepared by performing polymerase chain reaction experiments. This cDNA was used to probe mRNAs extracted from human pancreatic tissue and tumoral cell lines. Two mRNAs were detected in normal human pancreas at 2.2 and 1.3 to 1.5 kb. In human pancreatic tumoral cells, mRNAs encoding for the BSDL were detected using in situ hybridization, and proteins with an M(r) of 46,000 to 48,000 were translated into an in vitro system using mRNAs extracted from these cells. Using an immunoprecipitation procedure, we observed here that the specific BSDL polyclonal antibodies recognized three proteins of 100 +/- 5 (p100), 46 +/- 2 (p46) and 22.7 +/- 1.2 (p23) kDa, respectively in the soluble extracts of normal adult human pancreas. The p100 protein was probably the glycosylated product resulting from the translation of the 2.2 kb transcript. The p46 protein, which electrophoresed as a doublet was the main component immunoprecipitated from extract of a differentiated human pancreatic adenocarcinoma as well as from the extracts of two pancreatic cell lines, BxPC-3 and SOJ-6. In addition, the p46 immunoform of the BSDL was detected in cell-free medium from SOJ-6 cell line and its expression was found to be correlated with the secretion of an esterolytic activity on 4-nitrophenyl caproate, whereas the BxPC-3 cell line neither secreted the p46 nor showed any esterolytic activity on this substrate. The p46 may be either a short variant of BSDL resulting from the translation of the 1.3 to 1.5 kb transcript or a protein structurally related to the enzyme. The p46 doublet immunoform was detected in the human pancreatic secretion.
Assuntos
Lipase/análise , Proteínas de Neoplasias/análise , Neoplasias Pancreáticas/química , Esterol Esterase , Sequência de Bases , Northern Blotting , Ésteres , Humanos , Hibridização In Situ , Dados de Sequência Molecular , Peso Molecular , Proteínas de Neoplasias/biossíntese , Neoplasias Pancreáticas/enzimologia , Testes de Precipitina , Biossíntese de Proteínas , Células Tumorais CultivadasRESUMO
The human pancreatic cell line BxPC-3 displays two classes of binding sites with high and low affinity for VIP. The order of potency of VIP-related peptides in inhibiting either [125I]VIP or [125I]N-AcPACAP27 binding and in stimulating cAMP production was typical of the human VIP receptor. By combining affinity labeling with glycosidase treatments, we have characterized the VIP receptor as a M(r) = 68,200 glycoprotein, consisting of a M(r) = 39,300 polypeptide core with at least three N-linked oligosaccharide chains. In addition, our results revealed the presence of a low amount of sialic acid residues in the carbohydrate moiety of receptor.
Assuntos
Adenocarcinoma/química , Glicoproteínas/química , Neoplasias Pancreáticas/química , Receptores de Peptídeo Intestinal Vasoativo/química , Humanos , Oligossacarídeos/análise , Ensaio Radioligante , Células Tumorais CultivadasRESUMO
Bile salt-dependent lipase (BSDL, E.C. 3.1.1.-) is a digestive enzyme secreted by the pancreatic acinar cell. Once in the duodenum, the enzyme, upon activation by primary bile salts, hydrolyzes dietary lipid esters such as cholesteryl esters and lipid-soluble vitamin esters. This enzyme is partially transferred from the duodenum or pancreas to the circulation where it has been postulated to exert a systemic action on atheroma-generating oxidized-low density lipoprotein (LDL). In the present study, sera from 40 healthy normolipidemic volunteers were used to investigate the possible linkage between circulating BSDL, lipids, and lipoproteins. We showed, firstly, that pancreatic-like BSDL activity can be detected in these serums. Secondly, BSDL activity increased significantly with the level of LDL-cholesterol and was also positively linked to the serum concentration of Apo B100 and Apo A-I. Thirdly, we also established that BSDL was associated with LDL, in part by a specific interaction with Apo B100, while no interaction was found with Apo A-I. No linkage with other recorded parameters (triglycerides, phospholipids, and high density lipoprotein-cholesterol) was detected. Because an increase in LDL-cholesterol represents an important risk factor for atheroma, the concomitant increase in BSDL, which can metabolize atherogenic LDL, suggests for the first time that this circulating enzyme may exert a positive effect against atherosclerosis.
Assuntos
Ácidos e Sais Biliares/farmacologia , Lipídeos/sangue , Pâncreas/enzimologia , Esterol Esterase/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Apolipoproteína A-I/metabolismo , Apolipoproteína B-100 , Apolipoproteínas B/sangue , LDL-Colesterol/sangue , Duodeno/enzimologia , Feminino , Humanos , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Incisional hernia (IH) repair with conventional techniques is associated with high recurrence rate. Surgical repair using prosthetic biomaterials is becoming increasingly popular. On the basis of the good results an increasing number of surgeons have begun to use this technique. However prosthesis use in contaminated fields is still debated. In complicated IH contaminating surgical procedure are often performed and the use of meshes can be hazardous. The aim of this study was to report our experience about the treatment of complicated IH with prosthetic materials in an emergency surgery setting. METHODS: From November 1995 to November 2001 55 patients were submitted to emergency surgical treatment for complicated IH. Eleven patients were treated using a prosthetic device. Patients mean age was 71.3 (range 38-91). About 70% of patients had concomitant major cardiac or pulmonary diseases. RESULTS: Thirty-two IH were strangulated, 23 were incarcerated. In all patients a viscerolysis was carried out. In 6 patients a small bowel resection was done and in 4 subjects a large bowel resection was performed. Eight patients were submitted to omental resection. There were not differences in morbidity and mortality between the studied group. Recurrence rate was significantly lower in prosthetic treated group. CONCLUSIONS: We concluded that prosthetic repair of complicated IH is feasible in selected cases allowing abdominal wall anatomy re-establishment.
Assuntos
Tratamento de Emergência , Hérnia Ventral/complicações , Hérnia Ventral/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Perfuração Intestinal/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Telas Cirúrgicas , Resultado do TratamentoRESUMO
BACKGROUND: The availability of drugs which can effectively inhibit gastric secretion allowed the control of the peptic disease in almost all the patients, but the incidence of complications is substantially unchanged. METHODS: In the present study, we performed a retrospective evaluation of 153 patients treated for complicated peptic ulcer (hemorrhage and perforation) in the last 6 years. Hemor-rhage is a common onset of the peptic disease and it rarely requires a surgical treatment, because medical and endoscopic therapies are successful in a high number of patients. RESULTS: Surgery was necessary in 17.2% of the cases in the group of patients studied. CONCLUSIONS: Our experience confirms the high operative mortality in the patients who underwent surgery for hemorrhage related to complicated peptic ulcer because of the frequent presence of several risk factors. Surgical therapy is the main procedure of treatment of perforated peptic ulcer and in the group of patient examined all the cases of perforation underwent surgical operation. In conclusion, despite the progress of pharmacological and endoscopic therapies, surgical treatment is the best therapy of complicated peptic ulcer.
Assuntos
Úlcera Péptica/complicações , Úlcera Péptica/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
The gallbladder volvulus is a very rare but extremely dangerous event. Described for the first time by Wendel in 1898, it affects more frequently the female sex, particularly in old age. The clinical case of a patient affected by this pathology, personally observed, is presented and the initial symptoms, diagnostic procedures and surgical intervention are described in detail. The anatomical and physiological backgrounds that permit the gallbladder to twist on its axis are analysed and finally the importance of an early diagnosis to avoid the complications of a bilious peritonitis is underlined. In any case the definite diagnosis is made more frequently during surgical intervention. An early intervention allows a rapid resolution of the clinical picture preventing the perforation of the viscus into the peritoneal cavity and the complication of a bilious peritonitis besides the spreading of the biliary stones into the abdominal cavity.
Assuntos
Colecistectomia , Doenças da Vesícula Biliar/cirurgia , Idoso , Idoso de 80 Anos ou mais , Colelitíase/complicações , Feminino , Vesícula Biliar/irrigação sanguínea , Vesícula Biliar/patologia , Gangrena , Humanos , Isquemia/etiologia , Isquemia/cirurgia , Necrose , Peritonite/prevenção & controle , Anormalidade Torcional/complicações , Anormalidade Torcional/cirurgiaRESUMO
Meckel's diverticulum is the most common congenital abnormality of the intestinal tract, occurring in 2% of autoptic studies. The case of an 85-year-old man referred to the Emergency Surgery Unit for intestinal obstruction and lower gastrointestinal tract bleeding is reported. Surgical exploration revealed a complicated Meckel's diverticulum full of coproliths, immersed in pus and blood. Examination of the resected diverticulum showed necrotic diverticulitis in the absence of ectopic gastric or pancreatic tissues.
Assuntos
Divertículo Ileal/cirurgia , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Impacção Fecal/diagnóstico , Impacção Fecal/etiologia , Impacção Fecal/patologia , Impacção Fecal/cirurgia , Humanos , Masculino , Divertículo Ileal/complicações , Divertículo Ileal/diagnóstico , Divertículo Ileal/patologiaRESUMO
AIM: In elderly people colorectal cancer has an high incidence of emergency presentation. In this article we report our experience on colorectal emergency surgery for cancers in patients older than 80 yrs. METHODS: From October 1995 to December 2000 323 patients were submitted to emergency surgical procedure for colorectal cancer at the Dpt of Emergency Surgery of University of Bologna. 37 (11%) subjects were over 80 years of age. A retrospective analysis was performed: the data collected included the mode of presentation of the patients, the location and Dukes' classification of the tumors, the incidence of radical and palliative operations, the causes of death and 30-day mortality. RESULTS: The most common emergency presentation was an intestinal occlusion (21 cases); the other different presentations were peritonitis (7 cases) and hemorrhage (9 cases). 22 patients underwent resection of the primary growth and anastomosis and 11 subjects had palliative intervention by creating a stoma only or bypass anastomosis without resection, 2 patients had an explorative laparotomy and 2 were inoperable. Our overall postoperative mortality was 14.2% and we registered 1 anastomotic leakage. DISCUSSION AND CONCLUSIONS: Emergency surgery for colorectal cancer in patients over 80 years of age can be performed safely without restrictions related to the age.
Assuntos
Idoso , Neoplasias Colorretais/cirurgia , Fatores Etários , Idoso de 80 Anos ou mais , Causas de Morte , Neoplasias Colorretais/complicações , Neoplasias Colorretais/mortalidade , Emergências , Feminino , Humanos , Masculino , Cuidados Paliativos , Estudos Retrospectivos , Fatores Sexuais , Fatores de TempoRESUMO
An adult male underwent a bowel transplant for tufting enteropathy, receiving alemtuzumab, tacrolimus, and steroids as immunosuppressants. Five years later, he developed an autoimmune hemolytic anemia (AIHA), anti-IgG positive, with reduced reticulocyte count, leukopenia, and thrombocytopenia with antiplatelet antibodies. After an unsuccessful initial treatment with high dose steroids, reduction in tacrolimus dose, and intravenous immunoglobulin (IVIG), a bone marrow biopsy revealed absence of erythroid maturation with precursor hyperplasia. The patient was switched to sirolimus and received four doses of rituximab plus two courses of plasmapheresis, which decreased his transfusion requirements. After a febrile episode one month later, the AIHA relapsed with corresponding decreases in platelet and leukocyte count: cyclosporine A (CsA) was started with a second course of rituximab and IVIG without response, even though repeat bone marrow biopsy did not reveal morphology correlated to an acquired pure red cell aplasia (APRCA). Considering the similarity in his clinical and laboratory findings to APRCA, alemtuzumab was added (three doses over a week) with CsA followed by steroids. The patient was eventually discharged transfusion-independent, with increasing hemoglobin (Hb) levels and normal platelet and leukocyte count. One year later he is still disease-free with functioning graft.
RESUMO
Sites contaminated with hazardous material are a topical and urgent problem all over the world. In accordance with recent Italian regulations, appropriate risk assessment is required in order to determine health risks associated with contaminated sites. The paper presents a case study regarding a disused industrial plant contaminated with polycyclic aromatic hydrocarbons, heavy hydrocarbons and polychlorinated biphenyls. The site is characterized by three different topographical levels. Therefore both the characterization and the conceptual model had to be adapted to the site conditions: we divided the site into three discrete areas and we developed a separate risk assessment for each area. Besides health risk assessment, we performed ecological risk assessment for both groundwater and surface water targets, as required by Italian regulations. The future reuse scenario has not yet been defined and, consequently, risk assessment results will be useful for the remediation program. Risk assessment was supported by leaching tests and hydrocarbon "finger printing". Leaching tests allowed us to determine site-specific soil-water partition coefficient. Hydrocarbon "finger printing" allowed us to differentiate the mobility of the different hydrocarbon groups in migration analyses. We found the site required remediation based on Italian standard. We propose a simple risk-based remediation action consisting in the replacement of the upper 1m with "clean" soil and the placement of a barrier to vapors.
Assuntos
Resíduos Industriais , Monitoramento Ambiental/métodos , Geografia , Humanos , Hidrocarbonetos/toxicidade , Itália , Bifenilos Policlorados/análise , Risco , Medição de Risco , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Movimentos da Água , Poluentes Químicos da Água/toxicidade , Abastecimento de ÁguaRESUMO
BACKGROUND/AIMS: Gastrointestinal stromal tumors (GISTs) are a rare group of neoplasias of the gastrointestinal tract that have not yet been fully investigated. In this article the authors present the experience of an emergency surgery department in the diagnosis and treatment of patients with such neoplasms and discuss the approaches to these 'strange' tumors. METHODS: A review of our 4-year experience in emergency surgery was performed and 9 patients were found with the diagnosis of GIST. The median follow-up was 32.3 (range 18-45) months. RESULTS: 7 patients had evidence of gastrointestinal blood loss, 1 patient had abdominal pain, and the last patient had anorexia, vomiting and fever. Five tumors were located in the stomach and 4 in the small bowel. All the patients underwent complete resection. On histological examination 5 tumors were of myogenic origin, 1 was a gastrointestinal autonomic nerve tumor and 1 was a mixed neural-myoid tumor. The remaining 2 could not be differentiated. Of the 9 patients who underwent curative resections, 1 had a recurrence and died. CONCLUSION: GIST treatment mainly involves surgical resection with the goal of complete removal which can be curative. The histologic grade and tumor size are the most important prognostic factors.
Assuntos
Neoplasias do Íleo/cirurgia , Neoplasias do Jejuno/cirurgia , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Serviço Hospitalar de Emergência , Feminino , Humanos , Neoplasias do Íleo/diagnóstico , Neoplasias do Jejuno/diagnóstico , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/diagnósticoRESUMO
Bile salt-dependent lipase (BSDL) was detected in human SOJ-6 and rat AR4-2J pancreatic cells. Whereas AR4-2J cells actively secreted the enzyme, BSDL was retained within the Golgi compartment of SOJ-6 cells. Because Rab6 is involved in vesicle transport in the Golgi apparatus and the trans-Golgi network, we confirmed the presence of Rab6 in these cells. In rat AR4-2J cells, Rab6 as well as Rab1A/B and Rab2, partitioned between the cytosol and microsomes. In SOJ-6 cells Rab1A/B and Rab2 also partitioned between the cytosol and microsomes, but Rab6 was strictly associated with microsome membranes, suggesting a specific defect of Rab6 cycling in human SOJ-6 cells. The apparent defect of cycling in these cells is not due to the expression of a defective Rab6 since its correct sequence was confirmed. We further demonstrated that AR4-2J and SOJ-6 cells express the Rab-GDIbeta and Rab-GDIalpha isoforms, respectively. However, the sequence of Rab-GDIbeta, which may be the main form expressed by SOJ-6 cells, identified a few substitutions located in regions that are essential for Rab-GDI function. We conclude that the deficient secretion of BSDL by SOJ-6 cells could be due to the expression of defective Rab-GDIbeta. In spite of the alterations in Rab-GDIbeta, membrane proteins such as CD71 and NHE3 were correctly localized to the cell plasma membrane of SOJ-6 cells, suggesting that two functional distinct secretory pathway coexist in pancreatic cells.
Assuntos
Neoplasias Pancreáticas/enzimologia , Esterol Esterase/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Ácidos e Sais Biliares/metabolismo , Transporte Biológico Ativo , Primers do DNA/genética , Inibidores de Dissociação do Nucleotídeo Guanina/genética , Inibidores de Dissociação do Nucleotídeo Guanina/metabolismo , Humanos , Glicoproteínas de Membrana/metabolismo , Dados de Sequência Molecular , Mutação , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Ratos , Homologia de Sequência de Aminoácidos , Esterol Esterase/genética , Células Tumorais Cultivadas , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismoRESUMO
Peach shoot volatiles were attractive to mated female oriental fruit moth, Cydia molesta (Busck), in a dual choice arena. No preference was observed between leaf odours from the principle host plant, peach, and the secondary host plant, apple. Twenty-two compounds were identified in headspace volatiles of peach shoots using gas chromatography-mass spectrometry. Green leaf volatiles accounted for more than 50% of the total emitted volatiles. A bioassay-assisted fractionation using different sorbent polymers indicated an attractant effect of compounds with a chain length of 6-8 carbon atoms. The major compounds of this fraction were tested either singly or in combinations for behavioural response of females. Significant bioactivity was found for a three-component mixture of (Z)-3-hexen-1-yl acetate, (Z)-3-hexen-1-ol and benzaldehyde in a 4:1:1 ratio. This synthetic mixture elicited a similar attractant effect as the full natural blend from peach shoots as well as the bioactive fraction.
Assuntos
Lepidópteros/fisiologia , Malus/química , Odorantes/análise , Prunus/química , Animais , Bioensaio/veterinária , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Malus/parasitologia , Brotos de Planta/química , Prunus/parasitologia , VolatilizaçãoRESUMO
1. Pancreatic bile-salt-dependent lipase has been detected in human plasma where it has the capability to modify normal low- and high-density lipoprotein composition and structure and to reduce the atherogenicity of oxidized low-density lipoprotein (Shamir R, Johnson WJ, Morlock-Fitzpatrick K, Zolfaghari R, Li L, Mas E, Lombardo D, Morel DW, Fisher EA. Pancreatic carboxyl ester lipase: a circulating enzyme that modifies normal and oxidized lipoproteins in vitro. J Clin Invest 1996; 97: 1696-704). 2. In the present study, we investigated the effect of glycation and particularly that of human serum albumin on the activity of bile-salt-dependent lipase. In vitro, bile-salt-dependent lipase activity decreased in the presence of human serum albumin; however, this was less pronounced in the presence of glycated human serum albumin. In vivo, bile-salt-dependent lipase specific activity was about 2-fold higher in the sera of diabetic patients than in the sera of normal subjects. 3. A significant increase in the specific activity of bile-salt-dependent lipase related to the serum level of glycation was observed. The increase in bile-salt-dependent lipase specific activity was not related to the glucose concentration in serum suggesting that glycation of bile-salt-dependent lipase could not be involved in the observed effects. Although the stability of serum bile-salt-dependent lipase was important enough to allow a systemic action of the enzyme on lipoproteins, it could not explain the higher activity of the enzyme in diabetic serum. 4. We concluded that bile-salt-dependent lipase could be helpful against the premature development of atherosclerosis in diabetes.
Assuntos
Diabetes Mellitus Tipo 1/enzimologia , Lipase/metabolismo , Albumina Sérica/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Ácidos e Sais Biliares/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Ácidos Graxos/metabolismo , Feminino , Frutosamina/sangue , Glicosilação , Humanos , Lipase/sangue , Masculino , Pessoa de Meia-Idade , Testes de PrecipitinaRESUMO
Bile-salt-dependent lipase (BSDL) is secreted by the pancreas into the duodenum, where it catalyses the hydrolysis of dietary lipid esters on activation by bile salts. The secretion pathway of BSDL is comparable with that of other digestive enzymes produced by pancreatic acinar cells. However, in contrast with these other enzymes, BSDL is partly associated with endoplasmic reticulum membranes as part of a folding complex, including a Grp94-related protein to which BSDL is transiently linked. The release of BSDL from membranes occurs once its glycosylation is completed [Bruneau and Lombardo (1995) J. Biol. Chem. 270, 13524-13533]. In the present study, investigations concerning the mechanism of association/dissociation of BSDL with membranes of microsomes were performed. For this purpose the role of ATP and that of the possible phosphorylation of BSDL were examined. For the first time, it is shown that human pancreatic BSDL is phosphorylated, probably at a serine residue, during its transport within the acinar cell. The phosphorylation of BSDL is provoked by calphostin C, an inhibitor of protein kinase C. In the presence of 1-(isoquinolinesulphonyl)2-methylpiperazine, a non-specific inhibitor of serine/threonine protein kinase A, C or G, or of calcium chelator 1,2-bis(O-aminophenoxy)ethane-N,N,N', N'-tetra-acetic tetra(acetoxymethyl)ester, the phosphorylation of BSDL elicited by calphostin C is abolished. These data suggested that the phosphorylation of BSDL within human pancreatic microsomes is under the control of a cascade of protein kinases. We have also shown that the phosphorylation of BSDL appears to be involved in the release of the enzyme from microsome membranes. Nevertheless ATP, which modifies the conformation of BSDL, triggers this association, and an unhydrolysable ATP analogue was unable to promote it.