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1.
Prostate ; 83(8): 765-772, 2023 06.
Article in English | MEDLINE | ID: mdl-36895160

ABSTRACT

INTRODUCTION: Active surveillance (AS) is considered a suitable management practice for those patients with low-risk prostate cancer (PCa). At present, however, the role of multiparametric magnetic resonance imaging (mpMRI) in AS protocols has not yet been clearly established. OUTCOMES: To determine the role of mpMRI and its ability to detect significant prostate cancer (SigPCa) in PCa patients enrolled in AS protocols. MATERIALS AND METHODS: There were 229 patients enrolled in an AS protocol between 2011 and 2020 at Reina Sofía University Hospital. MRI interpretation was based on PIRADS v.1 or v.2/2.1 classification. Demographics, clinical, and analytical data were collected and analyzed. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for mpMRI in different scenarios. We defined SigPCa and reclassification/progression as a Gleason score (GS) ≥ 3 + 4, a clinical stage ≥T2b, or an increase in PCa volume. Kaplan-Meier and log-rank tests were used to estimate progression-free survival time. RESULTS: Median age was 69.02 (±7.73) at diagnosis, with a 0.15 (±0.08) PSA density (PSAD). Eighty-six patients were reclassified after confirmatory biopsy, with a suspicious mpMRI an indication for a clear reclassification and risk-predictor factor in disease progression (p < 0.05). During follow-up, 46 patients were changed from AS to active treatment mainly due to disease progression. Ninety patients underwent ≥2mpMRI during follow-up, with a median follow-up of 29 (15-49) months. Thirty-four patients had a baseline suspicious mpMRI (at diagnostic or confirmatory biopsy): 14 patients with a PIRADS 3 and 20 patients with ≥PIRADS 4. From 14 patients with a PIRADS 3 baseline mpMRI, 29% progressed radiologically, with a 50% progression rate versus 10% (1/10 patients) for those with similar or decreased mpMRI risk. Of the 56 patients with a non-suspicious baseline mpMRI (PIRADS < 2), 14 patients (25%) had an increased degree of radiological suspicion, with a detection rate of SigPCa of 29%. The mpMRI NPV during follow-up was 0.91. CONCLUSION: A suspicious mpMRI increases the reclassification and disease progression risk during follow-up and plays an important role in monitoring biopsies. In addition, a high NPV at mpMRI follow-up can help to decrease the need to monitor biopsies during AS.


Subject(s)
Prostatic Neoplasms , Watchful Waiting , Male , Humans , Aged , Prostate/pathology , Prostatic Neoplasms/pathology , Magnetic Resonance Imaging/methods , Magnetic Resonance Spectroscopy , Disease Progression , Image-Guided Biopsy/methods
2.
Sci Rep ; 10(1): 11519, 2020 Jul 08.
Article in English | MEDLINE | ID: mdl-32636438

ABSTRACT

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

3.
Sci Rep ; 10(1): 7346, 2020 04 30.
Article in English | MEDLINE | ID: mdl-32355193

ABSTRACT

The impact of an enhanced recovery after surgery (ERAS) programme in emergency colorectal surgery has not yet been reported. The objective of this study was to evaluate the feasibility and the results of patients included in an ERAS protocol following emergency colon surgery for left colon perforation. For this purpose, patients with a low to moderate risk of mortality, according to a Peritonitis Severity Score (PSS), and treated with an ERAS protocol (ERAS group) after emergency surgery for left colon perforation were compared for a period of 40 months (March 2014-June 2017) with a control group of patients treated with conventional care (CC group) during the 38 months prior to implementation of the new ERAS protocol (January 2011-February 2014). The main endpoint was 90-day postoperative morbidity according to the Clavien-Dindo classification. Secondary endpoints included length of postoperative hospital stay, 90-day readmission rate, protocol compliance and mortality. Fifty patients were included in the study, 29 in the ERAS group and 21 in the CC group. There were no significant differences between the groups in the demographic data or in the operative characteristics. A reduction in the incidence of postoperative complications (20.7% vs. 38%; p > 0.05) and in the postoperative hospital stay (7.7 + /- 3.85 vs. 10.9 + /- 5.6 days; p = 0.009) were observed in the ERAS group. The 90-day readmission rate did not differ significantly between the two groups (2 vs. 1). No 90-day mortality was observed in either group. The ERAS group showed better results than the CC group in protocol compliance. We conclude that ERAS protocols are feasible and help to reduce morbidity and length of hospital stay without adversely affecting the rate of readmission or mortality.


Subject(s)
Colon/surgery , Colonic Diseases/surgery , Digestive System Surgical Procedures/methods , Digestive System Surgical Procedures/adverse effects , Emergency Service, Hospital , Female , Humans , Male , Middle Aged , Postoperative Care , Postoperative Complications , Prospective Studies , Retrospective Studies
4.
Actas Urol Esp ; 41(3): 172-180, 2017 Apr.
Article in English, Spanish | MEDLINE | ID: mdl-27726892

ABSTRACT

OBJECTIVE: To determine the differential protein expression of biomarkers FGFR3, PI3K (subunits PI3Kp110α, PI3KClassIII, PI3Kp85), AKT, p21Waf1/Cip1 and cyclins D1 and D3 in T1 bladder cancer versus healthy tissue and to study their potential role as early recurrence markers. MATERIAL AND METHOD: This is a prospective study that employed a total of 67 tissue samples (55 cases of T1 bladder tumours that underwent transurethral resection and 12 cases of adjacent healthy mucosa). The protein expression levels were assessed using Western blot, and the means and percentages were compared using Student's t-test and the chi-squared test. The survival analysis was conducted using the Kaplan-Meier method and the log-rank test. RESULTS: Greater protein expression was detected for FGFR3, PI3Kp110α, PI3KClassIII, cyclins D1 and D3 and p21Waf1/Cip1 in the tumour tissue than in the healthy mucosa. However, these differences were not significant for PI3Kp85 and AKT. We observed statistically significant correlations between early recurrence and PI3Kp110α, PI3KClassIII, PI3Kp85 and AKT (P=.003, P=.045, P=.050 and P=.028, respectively), between the tumour type (primary vs. recurrence) and cyclin D3 (P=.001), between the tumour size and FGFR3 (P=.035) and between multifocality and cyclin D1 (P=.039). The survival analysis selected FGFR3 (P=.024), PI3Kp110α (P=.014), PI3KClassIII (P=.042) and AKT (P=.008) as markers of early-recurrence-free survival. CONCLUSIONS: There is an increase in protein expression levels in bladder tumour tissue. The overexpression of FGFR3, PI3Kp110α, PI3KClassIII and AKT is associated with increased early-recurrence-free survival for patients with T1 bladder tumours.


Subject(s)
Urinary Bladder Neoplasms/metabolism , Urinary Bladder Neoplasms/mortality , Aged , Aged, 80 and over , Cyclin D1/biosynthesis , Cyclin D2/biosynthesis , Cyclin-Dependent Kinase Inhibitor p21/biosynthesis , Female , Humans , Male , Middle Aged , Neoplasm Staging , Oncogene Protein v-akt/biosynthesis , Phosphatidylinositol 3-Kinases/biosynthesis , Prognosis , Prospective Studies , Receptor, Fibroblast Growth Factor, Type 3/biosynthesis , Survival Analysis , Urinary Bladder Neoplasms/pathology , Urinary Bladder Neoplasms/surgery
5.
Transplant Proc ; 48(9): 2895-2898, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27932101

ABSTRACT

INTRODUCTION: Nowadays, the number of patients receiving a second graft is growing, and the management of failed grafts is still controversial. OBJECTIVE: Our objective was to analyze the influence of graft nephrectomy on graft and patient survival. MATERIALS AND METHODS: We retrospectively evaluated the demographic features and graft outcomes of 63 recipients who received second allografts between August 1985 and April 2013. They were divided into two groups: group A, those who underwent nephrectomy of failed graft (n = 21, 33.3%), and group B, those whose failed graft was retained (n = 42, 66.6%). χ2 and Mann-Whitney U tests were used to compare demographic characteristics and graft features in both groups. Kaplan-Meier test was used to analyze graft and patient survival. Finally, univariate and multivariate analysis was done using Cox regression. RESULTS: Demographic characteristics of donor and receptors were similar in both groups. Overall panel-reactive antibody (P = .040) showed statistically significant differences between groups (72.0 ± 25.3 in group A and 54.8 ± 30.0 in group B). Hemodialysis duration was longer in group A (P = .023, 112.2 ± 72.8 vs 70.9 ± 66.9 months). The percentage of patients who had delayed graft function was higher in group A (58.8% vs 27.3%, P = .029). Kaplan-Meier test found no differences between groups (P = .344); group A, 107.4 months (95% confidence interval [CI] 74.0 to 140.8) and group B, 82.7 months (95% CI 62.5 to 102.8). We found no differences in terms of patient survival (P = .798) with the Kaplan-Meier test. In group A, patient survival was 164.5 months (CI 137.7 to 191.31) and in group B, 152.0 months (95% CI 125.5 to 178.5). CONCLUSIONS: Failed graft nephrectomy did not show a negative impact on graft and patient survival.


Subject(s)
Allografts/physiology , Graft Rejection/mortality , Graft Survival/physiology , Kidney Transplantation/mortality , Nephrectomy/mortality , Adult , Delayed Graft Function/mortality , Delayed Graft Function/physiopathology , Female , Graft Rejection/immunology , Graft Rejection/physiopathology , Humans , Immunosuppressive Agents/therapeutic use , Kaplan-Meier Estimate , Kidney Failure, Chronic/mortality , Kidney Failure, Chronic/surgery , Male , Middle Aged , Multivariate Analysis , Renal Dialysis/mortality , Reoperation , Retrospective Studies , Time Factors , Tissue Donors , Transplantation, Homologous/mortality
6.
Actas urol. esp ; 37(8): 504-512, sept. 2013. tab
Article in Spanish | IBECS | ID: ibc-116560

ABSTRACT

Objetivos: Evaluar el significado de la invasión microvascular y de otras variables clínicas e histológicas como factores predictivos de supervivencia libre de progresión y supervivencia cáncer-específica de pacientes con carcinoma renal tras cirugía. Material y métodos: Se realizó un estudio analítico retrospectivo sobre 238 pacientes consecutivos con carcinoma renal sometidos a cirugía radical o parcial entre 1990 y 2006, incluyendo tanto casos de enfermedad localizada como aquellos con afectación locorregional o con enfermedad metastásica a distancia en el momento del diagnóstico (pT1-4; N0-1; M0-1). Se evaluó la supervivencia libre de progresión y la supervivencia cáncer-específica tras un seguimiento medio de 75 meses (rango: 1-189). Las variables analizadas incluyeron: edad, sexo, tamaño tumoral, clasificación TNM 2010, gradación nuclear, subtipo histológico e invasión microvascular. Resultados: Se evidenció existencia de invasión microvascular en 79 casos (33,2%). La presencia de invasión microvascular tumoral en el estudio histológico se asoció estadísticamente con la edad (p = 0,010), el tamaño tumoral (p = 0,000), el grado de Fuhrman (p = 0,000), el estadio pT 2010 (p = 0,000), el estadio N 2010 (p = 0,000) y el estadio M 2010 (p = 0,000). En el análisis múltiple las variables que finalmente se mostraron como factores predictores de supervivencia libre de progresión fueron el sexo, el grado de Fuhrman, el estadio pT y el tipo histológico, mientras que lo fueron para supervivencia cáncer específica el sexo, el grado de Fuhrman, el estadio pT 2010, el estadio M 2010, el tipo histológico y la invasión microvascular. Conclusiones: Los resultados de nuestro estudio muestran que la invasión microvascular es un factor predictor de supervivencia cáncer-específica en pacientes con carcinoma renal (AU)


Objective: To assess microvascular tumor invasion and other clinical and histological parameters as potential prognostic factors in surgically treated renal cell carcinoma. Materials and methods: Surgical specimens from 238 consecutive patients who underwent radical or partial surgery between 1990 and 2006 were retrospectively evaluated. The series included clinically localized or metastatic renal cell carcinoma (pT1-4; N0-1; M0-1). Disease-free and cancer-specific survival assessments were the end points with median follow-up of 75 months (range 1-189 months). Variables studied included: age, sex, tumor size, TNM 2010 classification, Fuhrman grade, histological subtype and microvascular tumor invasion. Results: Microvascular tumor invasion was observed in 79 patients (33,2%) and was significantly associated with age (P =0 .010), tumor size (P =0 .000), Fuhrman grade (P = 0.000), pT stage 2010 (P = 0.000), N stage 2010 (P =0 .000) and M stage 2010 (P = 0.000). Multivariate analyses determined that sex, Fuhrman grade, pT stage 2010 and histological subtipe were independent prognostic factors of disease-free survival, while sex, Fuhrman grade, pT stage 2010, M stage 2010, histological subtype and microvascular invasion were prognostic factors for cancer-specific survival. Conclusions: Our study shows that microvascular tumor invasion is an independent prognostic factor for cancer-specific survival in surgically treated patients with renal cell carcinoma (AU)


Subject(s)
Humans , Carcinoma, Renal Cell/pathology , Kidney Neoplasms/pathology , Neoplasm Invasiveness/pathology , Retrospective Studies , Disease-Free Survival
7.
Actas Urol Esp ; 37(8): 504-12, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23623182

ABSTRACT

OBJECTIVE: To assess microvascular tumor invasion and other clinical and histological parameters as potential prognostic factors in surgically treated renal cell carcinoma. MATERIALS AND METHODS: Surgical specimens from 238 consecutive patients who underwent radical or partial surgery between 1990 and 2006 were retrospectively evaluated. The series included clinically localized or metastatic renal cell carcinoma (pT1-4; N0-1; M0-1). Disease-free and cancer-specific survival assessments were the end points with median follow-up of 75 months (range 1-189 months). Variables studied included: age, sex, tumor size, TNM 2010 classification, Fuhrman grade, histological subtype and microvascular tumor invasion. RESULTS: Microvascular tumor invasion was observed in 79 patients (33,2%) and was significantly associated with age (P=.010), tumor size (P=.000), Fuhrman grade (P=.000), pT stage 2010 (P=.000),N stage 2010 (P=.000) and M stage 2010 (P=.000). Multivariate analyses determined that sex, Fuhrman grade, pT stage 2010 and histological subtipe were independent prognostic factors of disease-free survival, while sex, Fuhrman grade, pT stage 2010, M stage 2010, histological subtype and microvascular invasion were prognostic factors for cancer-specific survival. CONCLUSIONS: Our study shows that microvascular tumor invasion is an independent prognostic factor for cancer-specific survival in surgically treated patients with renal cell carcinoma.


Subject(s)
Carcinoma, Renal Cell/mortality , Carcinoma, Renal Cell/pathology , Kidney Neoplasms/mortality , Kidney Neoplasms/pathology , Microvessels , Vascular Neoplasms/mortality , Vascular Neoplasms/pathology , Adult , Carcinoma, Renal Cell/surgery , Disease-Free Survival , Female , Humans , Kidney Neoplasms/surgery , Male , Middle Aged , Neoplasm Invasiveness , Prognosis , Retrospective Studies , Survival Rate
8.
Med. intensiva (Madr., Ed. impr.) ; 35(5): 274-279, jun.-jul. 2011. ilus, tab
Article in Spanish | IBECS | ID: ibc-92806

ABSTRACT

ObjetivoAnalizar la correlación entre la presión intraabdominal e intratorácica en pacientes con sospecha de hipertensión intraabdominal (HIA).DiseñoEstudio prospectivo observacional de una cohorte.ÁmbitoUnidad de medicina intensiva polivalente de un hospital universitario.PacientesSe incluyó a 27 pacientes medicoquirúrgicos dependientes de ventilación mecánica controlada por fallo respiratorio agudo y con factores de riesgo de hipertensión intraabdominal.Principales variablesMedimos las presiones intraabdominal (PIA), esofágica (Peso) y de la vía aérea en condiciones estáticas (est) y dinámicas (din). Calculamos la distensibilidad del sistema respiratorio (Csr), pulmón (Cp) y pared torácica (Cpt).ResultadosEn 10 pacientes la PIAest fue mayor de 12mmHg (HIA, PIAest, 14±2 [12-21] mmHg) y en el resto fue normal (n=17; PIAest, 8±2 [3-11] mmHg). La Pesoest fue 11±5 (2-27) y Pesodin, 7±4 (2-24) cmH2O. Considerando la presencia o no de HIA, Pesoest fue 9±4 vs. 7±3cmH2O (p=0,2) y Pesodin, 6±2 vs. 4±3cmH2O (p=0,3), respectivamente. La correlación de Pesoest y din con PIAest fue 0,5 (p=0,003) y 0,4 (p=0,03), respectivamente. Los componentes de la distensibilidad del sistema respiratorio estaban disminuidos (Csr, 31±8; Cp, 52±22; Cpt, 105±50ml/cmH2O), Cpt fue significativamente más baja en los pacientes con HIA (81±31 vs. 118±55ml/cmH2O; p=0,02). El coeficiente de correlación entre la PIAest y Cpt fue –0,7 (p<0,001) y de –0,5 (p=0,002) con Csr.ConclusionesLa pared torácica es más rígida en pacientes con hipertensión abdominal. En presencia de factores de riesgo de HIA las presiones en estos compartimentos son muy variables (AU)


Objective: To study the correlation between intraabdominal and intrathoracic pressure inpatients with suspected intraabdominal hypertension.Design: A prospective, observational cohort study.Setting: Polyvalent intensive care unit of a University hospital.Patients: Twenty-seven medical-surgical patient dependent upon controlled mechanical ventilationdue to acute respiratory failure and with several risk factors for intraabdominalhypertension (IAH).Main variables: Intraabdominal (IAP), esophageal (Peso) and airways pressure were measuredunder static (st) and dynamic (dyn) conditions. Respiratory system (Crs), lung (Cl) and chestwall compliance (Ccw)were calculated.Results: In 10 patients IAP > 12mmHg (IAH, IAPst, 14±2 [12-21] mmHg), while in the rest thepressure proved normal (n = 17; IAPst, 8±2 [3-11] mmHg). Peso st was 11±5 (2-27) and Pesodyn 7±4 (2-24) cmH2O. Depending on the presence or absence of IAH, Peso st was 9±4 vs7±3 cmH2O (p = 0.2) and Peso dyn 6±2 vs 4±3 cmH2O (p = 0.3), respectively. The correlationbetween Peso st and dyn with IAPst was 0.5 (p = 0.003) and 0.4 (p = 0.03), respectively. Thecompliance components were decreased (Crs, 31±8; Cl, 52±22 and Ccw, 105±50 ml/cmH2O);Ccw was significantly lower in patients with IAH (81±31 vs 118±55 ml/cmH2O; p = 0.02). Thecorrelation coefficient between IAPst and Ccw was —0.7 (p < 0.001), and —0.5 (p = 0.002) withrespect to Crs.Conclusions: A stiffer chest wall was observed in patients with IAH. In patients with risk factorsfor IAH, pressures in these compartments were highly variable (AU)


Subject(s)
Humans , Blood Pressure Determination/methods , Hypertension/diagnosis , Respiratory Insufficiency/therapy , Respiration, Artificial/adverse effects , Prospective Studies , Risk Factors
9.
Med Intensiva ; 35(5): 274-9, 2011.
Article in Spanish | MEDLINE | ID: mdl-21497415

ABSTRACT

OBJECTIVE: To study the correlation between intraabdominal and intrathoracic pressure in patients with suspected intraabdominal hypertension. DESIGN: A prospective, observational cohort study. SETTING: Polyvalent intensive care unit of a University hospital. PATIENTS: Twenty-seven medical-surgical patient dependent upon controlled mechanical ventilation due to acute respiratory failure and with several risk factors for intraabdominal hypertension (IAH). MAIN VARIABLES: Intraabdominal (IAP), esophageal (Peso) and airways pressure were measured under static (st) and dynamic (dyn) conditions. Respiratory system (Crs), lung (Cl) and chest wall compliance (Ccw)were calculated. RESULTS: In 10 patients IAP > 12 mmHg (IAH, IAPst, 14 ± 2 [12-21] mmHg), while in the rest the pressure proved normal (n = 17; IAPst, 8 ± 2 [3-11] mmHg). Peso st was 11 ± 5 (2-27) and Peso dyn 7 ± 4 (2-24) cmH2O. Depending on the presence or absence of IAH, Peso st was 9 ± 4 vs 7 ± 3 cmH2O (p = 0.2) and Peso dyn 6 ± 2 vs 4 ± 3 cmH2O (p = 0.3), respectively. The correlation between Peso st and dyn with IAPst was 0.5 (p= 0.003) and 0.4 (p = 0.03), respectively. The compliance components were decreased (Crs, 31 ± 8; Cl, 52 ± 22 and Ccw, 105 ± 50 ml/cmH2O); Ccw was significantly lower in patients with IAH (81 ± 31 vs 118 ± 55 ml/cmH2O; p = 0.02). The correlation coefficient between IAPst and Ccw was -0.7 (p < 0.001), and -0.5 (p = 0.002) with respect to Crs. CONCLUSIONS: A stiffer chest wall was observed in patients with IAH. In patients with risk factors for IAH, pressures in these compartments were highly variable.


Subject(s)
Abdominal Cavity , Hypertension/physiopathology , Thorax , Aged , Critical Illness , Female , Humans , Male , Pressure , Prospective Studies
10.
Microbiologia ; 12(4): 585-92, 1996 Dec.
Article in English | MEDLINE | ID: mdl-9018692

ABSTRACT

Beta-Galactosidase from mycelial extract of Aspergillus nidulans has been purified by substrate affinity chromatography and used to obtain anti-beta-galactosidase polyclonal antibodies. A. nidulans growing in lactose as carbon source synthesizes one active form of beta-galactosidase which seems to be a multimeric enzyme of 450 kDa composed of monomers with 120 and 97 kDa. Although the enzyme was not released to the culture medium, some enzymatic activity was detected in a cell-wall extract, thus suggesting that it can be an extracellular enzyme. Beta-Galactosidase of A. nidulans is a very unstable enzyme with an optimum pH value of 7.5 and an optimum temperature of 30 degrees C. It was only active against beta-galactoside substrates like lactose and p-nitrophenyl-beta-D-galactoside (PNPG).


Subject(s)
Aspergillus nidulans/enzymology , beta-Galactosidase/isolation & purification , beta-Galactosidase/analysis
11.
Arch Microbiol ; 166(5): 336-41, 1996 Nov.
Article in English | MEDLINE | ID: mdl-8929280

ABSTRACT

Aspergillus nidulans is able to grow on oleic acid as sole carbon source. Characterization of the oleate-induced beta-oxidation pathway showed the presence of the two enzyme activities involved in the first step of this catabolic system: acyl-CoA oxidase and acyl-CoA dehydrogenase. After isopicnic centrifugation in a linear sucrose gradient, microbodies (peroxisomes) housing the beta-oxidation enzymes, isocitrate lyase and catalase were clearly resolved from the mitochondrial fraction, which contained fumarase. Growth on oleic acid was associated with the development of many microbodies that were scattered throughout the cytoplasm of the cells. These microbodies (peroxisomes) were round to elongated, made up 6% of the cytoplasmic volume, and were characterized by the presence of catalase. The beta-oxidation pathway was also induced in acetate-grown cells, although at lower levels; these cells lacked acyl-CoA oxidase activity. Nevertheless, growth on acetate did not cause a massive proliferation of microbodies in A. nidulans.


Subject(s)
Acyl-CoA Dehydrogenases/metabolism , Aspergillus nidulans/enzymology , Aspergillus nidulans/metabolism , Fatty Acids/metabolism , Microbodies/physiology , Acetates/metabolism , Acetyl-CoA C-Acetyltransferase/metabolism , Acyl-CoA Dehydrogenase , Aspergillus nidulans/ultrastructure , Catalase/metabolism , Culture Media/metabolism , Enoyl-CoA Hydratase/metabolism , Fumarate Hydratase/metabolism , Glucose/metabolism , Isocitrate Lyase/metabolism , Microbodies/enzymology , Microbodies/ultrastructure , Microscopy, Electron , Oleic Acid/metabolism , Oxidation-Reduction
12.
Microbiologia ; 11(4): 447-54, 1995 Dec.
Article in English | MEDLINE | ID: mdl-8588840

ABSTRACT

Twenty bacterial strains were isolated from a sample of contaminated heating oil and screened for their ability to use petroleum and several common fuels as the sole source of carbon and energy. One of the isolates, named MM5, was able to grow on petroleum derivatives and brought about an emulsification of those compounds. Gas chromatography studies showed that strain MM5 was able to degrade hydrocarbons of heating oil. MM5 has been tentatively identified as a strain of Acinetobacter calcoaceticus. The fine structure of MM5 was examined by transmission electron microscopy. Incubation in the presence of hydrocarbon substrates resulted in the development of intracellular electron-transparent inclusions. These structures were absent in the non-hydrocarbon cultures studied.


Subject(s)
Acinetobacter calcoaceticus/isolation & purification , Excipients , Fuel Oils/microbiology , Hydrocarbons/metabolism , Acinetobacter calcoaceticus/metabolism , Acinetobacter calcoaceticus/ultrastructure , Biodegradation, Environmental , Carbon/metabolism , Energy Metabolism , Microscopy, Electron , Petroleum
13.
J Virol ; 69(9): 5269-77, 1995 Sep.
Article in English | MEDLINE | ID: mdl-7636969

ABSTRACT

The binding domains of four monoclonal antibodies (MAbs) specific for the M protein of the PUR46-MAD strain of transmissible gastroenteritis coronavirus (TGEV) have been located in the 46 carboxy-terminal amino acids of the protein by studying the binding of MAbs to recombinant M protein fragments. Immunoelectron microscopy using these MAbs demonstrated that in a significant proportion of the M protein molecules, the carboxy terminus is exposed on the external surface both in purified viruses and in nascent TGEV virions that recently exited infected swine testis cells. The same MAbs specifically neutralized the infectivity of the PUR46-MAD strain, indicating that the C-terminal domain of M protein is exposed on infectious viruses. This topology of TGEV M protein probably coexists with the structure currently described for the M protein of coronaviruses, which consists of an exposed amino terminus and an intravirion carboxy-terminal domain. The presence of a detectable number of M protein molecules with their carboxy termini exposed on the surface of the virion has relevance for viral function, since it has been shown that the carboxy terminus of M protein is immunodominant and that antibodies specific for this domain both neutralize TGEV and mediate the complement-dependent lysis of TGEV-infected cells.


Subject(s)
Transmissible gastroenteritis virus/metabolism , Viral Matrix Proteins/analysis , Virion/metabolism , Animals , Antibodies, Monoclonal , Antigen-Antibody Reactions , Antigens, Viral/analysis , Cells, Cultured , Cloning, Molecular , Male , Mice/immunology , Microscopy, Immunoelectron , Models, Structural , Neutralization Tests , Protein Conformation , Recombinant Fusion Proteins/analysis , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/immunology , Swine , Testis , Transmissible gastroenteritis virus/ultrastructure , Viral Matrix Proteins/chemistry , Viral Matrix Proteins/immunology , Virion/ultrastructure
14.
J Gen Virol ; 76 ( Pt 8): 2075-80, 1995 Aug.
Article in English | MEDLINE | ID: mdl-7636490

ABSTRACT

The ultrastructure of human astrovirus serotype 2 (H-Ast2) grown in cell culture was analysed by electron microscopy of thin sections and negatively stained preparation. Infected LLCMK2 cells, as visualized in thin sections, contained cytoplasmic aggregates of dense or hollow-cored particles that aggregated in quasicrystalline arrays and were specifically labelled using a rabbit polyclonal anti-Ast2 antiserum. H-Ast2 particles from the supernatant of infected LLCMK2 cells in thin sections after flat- embedding were similar in size to intracellular virions. In negatively stained preparations, these virus particles had an external diameter of 41 nm and exhibited a well defined layer of surface spikes. Pentagonal and hexagonal contours were occasionally visible, and probably correspond to the projections of icosahedral structures. Star-like morphologies and particles with surface triangular hollows were seen in dark areas of the preparations only after a short treatment of the viruses of pH 10. Incubation of the viruses at pH 10.5 induced a rapid disassembly of the virus particles. The finding that the particles with icosahedral geometry and surface spikes are fully infective allows an alternative morphological model to the traditional one for astroviruses to be proposed.


Subject(s)
Mamastrovirus/ultrastructure , Cell Line , Cytoplasm/virology , Humans , Hydrogen-Ion Concentration , Inclusion Bodies, Viral/ultrastructure , Microscopy, Immunoelectron , Virion/ultrastructure
15.
FEMS Microbiol Lett ; 112(1): 35-41, 1993 Aug 15.
Article in English | MEDLINE | ID: mdl-8405947

ABSTRACT

alpha-Galactosidases from mycelial extract and culture filtrate of Aspergillus nidulans have been purified to homogeneity and utilised to obtain polyclonal antibodies anti-alpha-galactosidase. The enzymatic characteristics and the cross reactivity of the antibodies suggest that alpha-galactosidases isolated from the two sources were the same enzyme. Thus, A. nidulans synthesized and secreted only one enzymatic form of alpha-galactosidase which is a multimeric enzyme of 370 kDa composed of four monomers of 87 kDa and a pI of 6.3. The optimum temperature of activity was 50 degrees C and the optimum pH 4-5. The enzyme was stable over a wide range of pH but quite unstable to temperature. alpha-Galactosidase of A. nidulans is a very specific enzyme, it is active only on p-nitrophenyl-alpha-D-galactoside (PNPG), melibiose and raffinose. When PNPG was utilised as substrate melibiose, raffinose, galactose and glucose were competitive inhibitors of the activity.


Subject(s)
Aspergillus nidulans/enzymology , alpha-Galactosidase/isolation & purification , Enzyme Stability , Hydrogen-Ion Concentration , Immunochemistry , Molecular Weight , Protein Conformation , Temperature , alpha-Galactosidase/biosynthesis , alpha-Galactosidase/chemistry
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