Human adipose tissue-derived mesenchymal stromal cells as vehicles for tumor bystander effect: a model based on bioluminescence imaging

Human adipose tissue mesenchymal stromal cells (AMSCs) share common traits, including similar differentiation potential and cell surface markers, with their bone marrow counterparts. Owing to their general availability, higher abundance and ease of isolation AMSCs may be convenient autologous delivery vehicles for localized tumor therapy. We demonstrate a model for tumor therapy development based on the use of AMSCs expressing renilla luciferase and thymidine kinase, as cellular vehicles for ganciclovir-mediated bystander killing of firefly luciferase expressing tumors, and noninvasive bioluminescence imaging to continuously monitor both, tumor cells and AMSCs. We show that the therapy delivering AMSCs survive long time within tumors, optimize the ratio of AMSCs to tumor cells for therapy, and asses the therapeutic effect in real time. Treatment of mice bearing prostate tumors plus therapeutic AMSCs with the prodrug ganciclovir induced bystander killing effect, reducing the number of tumor cells to 1.5 % that of control tumors. Thus, AMSCs could be useful vehicles to deliver localized therapy, with potential for clinical application in inoperable tumors and surgical borders after tumor resection. This approach, useful to evaluate efficiency of therapeutic models, should facilitate the selection of cell types, dosages, therapeutic agents and treatment protocols for cell-based therapies of specific tumors.

Detection of numerous verotoxigenic E. coli serotypes, with multiple antibiotic resistance from cattle faeces and soil

Verotoxigenic E. coli (VTEC) belong to a diverse range of serotypes. Serotypes O157 and O26 are predominately identified in VTEC-associated disease in Europe, however due to difficulty in detection little is known about the epidemiology of non-O157 serotypes. This study reports the identification of 7 VTEC serotypes from cattle faeces and soil. Cattle faeces samples (n=128) were taken from animals in 6 different farms, with soil samples (n=20) obtained from 1 farm. After sample incubation in modified tryptone soy broth (mTSB) supplemented with streptomycin sulphate samples were plated onto sorbitol MacConkey (SMAC) also supplemented with streptomycin sulphate. Bacteria detected on the plates were subjected to biochemical testing, antibiotic resistance profiling, and PCR to detect typical virulence genes, beta-lactamase and class 1 integron associated genes. Serotyping was performed on isolates positive for virulence genes. E. coli was identified from 103 samples, with verotoxin genes present in 7 E. coli isolates. Of these 7 isolates, 5 were resistant to 5 or more antibiotics. The isolate resistant to 9 antimicrobials contained a class 1 integron structure. Serotyping identified 7 separate VTEC, O2:H27, O26:H11, O63:H(-), O148:H8, O149:H1, O174:H21 and ONT:H25. Six of these VTEC have been previously associated with human disease, however with the exception of O26:H11, these serotypes have been rarely reported worldwide. Increased surveillance is required to determine the prevalence of these and other non-O157 VTEC. The presence of multi-antibiotic resistance in these isolates is of concern, and the overall implications for public health must be ascertained.

Association between mortality of Escherichia coli meningitis in young infants and non-virulent clonal groups of strains

To identify factors associated with Escherichia coli meningitis (ECM) mortality in infants aged <3 months, the clinical, biological and bacterial characteristics of isolates from 99 cases of ECM were compared, including the phylogenetic group, multilocus sequence type, O serogroup and sequence O type (a combination of sequence type complex (STc) and O serogroup) and virulence genotype. All 99 isolates were susceptible to the initial antimicrobial treatment. The mortality rate (14%) was not influenced by term or post-natal age. Hypotension or seizures were the sole clinical predictive factors for fatal outcome (p <0.01), and abnormal initial trans-fontanellar ultrasound was associated with death (p 0.03). Seventy-seven isolates belonged to the common sequence O types (STc29(O1), STc29(O18), STc29(O45), STc301(O7), STc304(O16), STc697(O83), STc700(O1)) causing neonatal meningitis. None of the phylogenetic groups and none of the virulence determinants were distributed differently between survivors and non-survivors, except that the aerobactin gene (iucC) was less frequent in lethal isolates (94% vs. 71%, p 0.02). Isolates belonging to rare sequence O types were more likely to be lethal (OR 4.3, p 0.01), although they induced a lower level of bacteraemia than common sequence O types such as STc29(O18) and STc29(O45) in a neonatal rat model. These results suggest that unidentified human genetic risk-factors may be more important than strain virulence in predicting ECM mortality.

A longitudinal study of verotoxin-producing Escherichia coli in two dairy goat herds

A longitudinal study was conducted on two dairy farms to investigate the pattern of shedding of verotoxin-producing Escherichia coli (VTEC) in goats. Faecal samples were taken from 20 goat kids once weekly during the first 4 weeks of life and then once every month for the next 5 months of life, and from 18 replacement animals and 15 adults once every month for 12 months. The proportion of samples containing VTEC was higher for replacement animals and adults (85.7% and 78.7%, respectively) than for goat kids (25.4%). About 90% of the VTEC colonies isolated from healthy goats belonged to five serogroups (O33, O76, O126, O146 and O166) but the most frequent serogroups of these isolates, except one, were different in the two herds studied. E. coli O157:H7 was found in three goat kids on only one occasion. None of the VTEC isolates, except the three E. coli O157:H7 isolates, was eae-positive. The patterns of shedding of VTEC in goat kids were variable, but, in contrast, most of the replacement animals and adults were persistent VTEC shedders. Our results show that isolates of VTEC O33, O76, O126, O146 and O166 are adapted for colonising the intestine of goats but that, in contrast, infection with VTEC O157:H7 in goats seems to be transient.

Subacute renal failure in diabetic nephropathy due to endocapillary glomerulonephritis and cholesterol embolization

Patients with established diabetic nephropathy could have other glomerular diseases superimposed on diabetic glomerulosclerosis. Cholesterol embolization syndrome (CES) is a systemic disorder caused by cholesterol crystal embolization from ulcerated atherosclerosis plaques in the aorta and its major branches. Curiously, there are few papers describing the association between diabetic nephropathy and CES. On the other hand, the clinical picture of CES resembles systemic vasculitis, and there is a controversy regarding the association between CES and glomerular or vascular inflammation. We report a case of atypical CES that developed after cardiac catheterization in a diabetic man; it presented as subacute renal failure with proliferative and exudative endocapillary glomerulonephritis.

[Indicators of quality in the critical patient]

The utility of using quality indicators as a tool to measure the common practice and evaluate efficacy of measures established to improve quality has been demonstrated, making it possible to identify and make known the improvements carried out. The project "Quality indicators in the critical patient" has been conducted by the Spanish Society of Intensive and Critical Medicine (SEMICYUC) under the methodological management of the Foundation Avedis Donabedian (FAD) of Barcelona. Its objective was to develop key indicators in the care of the critical patient, considering the following as added values: reaching an agreement on the quality criteria in these patients and providing the professionals with a potent and reliable instrument for clinical evaluation and management, introducing common evaluation methods that make it possible to unify the measure, making a comparative evaluation (benchmarking), having information that makes it possible to develop quality plans (quantitative, objective, reliable and valid data) and having a system that assures total quality of care to the critical patient.

[Ancillary studies in the differential diagnosis of epithelial renal cell tumors with granular cells]

INTRODUCTION AND OBJECTIVES

Differential diagnosis of renal neoplasms with granular cells may pose difficulties and implications on ontogeny and prognosis. Our aims are to characterize the pattern of immunostaining and to search for a useful diagnosis panel.

METHODS

We studied with colloidal iron staining (Mowry's modified method) and 22 commonly used immunomarkers 22 conventional carcinomas (CC), 37 chromophobe carcinomas (CPC), 8 oncocytomas (OC), and 7 collecting duct carcinomas (CDC) with granular cells. Cases with not entirely clear diagnosis were excluded.

RESULTS

Colloidal iron staining was diffuse, strong, reticular, and cytoplasmic in 32 CPC cases, the diffuse and strong pattern was not observed in other tumors. The more useful diagnostic panel was cytokeratin 7 (CK7)/CD10/vimentine (vim). The 8 OC were negative for the three antibodies. The most common profile for CC was CK7-/CD10+/vim+, the CPC profile was CK7+/CD10-/vim-, and CDC did not show a particular profile. With these three antibodies specificity was >90% for the differential diagnosis. Adding colloidal iron staining specificity was 100%.

CONCLUSIONS

Morphologic features, colloidal iron staining (modified Mowry's method), and immunostaining with CK7/CD10/vim permit the final diagnosis with high specificity. However, a 100% specific marker does not exist at the present time.

Measurement of biofilm formation by clinical isolates of Escherichia coli is method-dependent

AIMS

In this study, we have evaluated the impact of methodological approaches in the determination of biofilm formation by four clinical isolates of Escherichia coli in static assays.

METHODS AND RESULTS

The assays were performed in microtitre plates with two minimal and two enriched broths, with one- or two-steps protocol, and using three different mathematical formulas to quantify adherent bacteria. Different biofilm formation patterns were found depending on the E. coli strain, culture medium and reading optical density on one- and two-steps protocol. Strong or moderate biofilm formation occurred mostly in minimal media. The mathematical formulas used to quantify biofilm formation also gave different results and bacterial growth rate should be taken into account to quantify biofilm.

CONCLUSIONS

Escherichia coli forms biofilms on static assays in a method-dependent fashion, depending on strain, and it is strongly modulated by culture conditions.

SIGNIFICANCE AND IMPACT OF THE STUDY

As verified in the studied E. coli strains, biofilm formation by any organism should be cautiously interpreted, considering all variables in the experimental settings.

Secondary amyloidosis associated with histiocytosis X

We report a 34-year-old man diagnosed with Langerhans cell histiocytosis (LCH) or histiocytosis X in 1980. He had multiple focal osseous lesions, difficult control of the disease activity and was treated many times with chemo- and radiotherapy for symptomatic control. His kidney disease started 20 years after the diagnosis with progressive renal failure and increasing non-nephrotic proteinuria, coinciding with two flares of LCH. A percutaneous renal biopsy demonstrated amyloidosis. There is only one case described in the amyloidosis literature associated with LCH.

Serotypes, virulence genes, intimin types and PFGE profiles of Escherichia coli isolated from piglets with diarrhoea in Slovakia

Two hundred and fifty Escherichia coli isolates from diarrhoeic and healthy piglets were serotyped and tested for the presence of virulence genes for fimbriae, intimin, heat-labile (LT) and heat-stable (STa and STb) enterotoxins, Stx toxins, and enteroaggregative heat-stable 1 (EAST1) enterotoxin by polymerase chain reaction (PCR). Although 220 isolates from diarrhoeic piglets belonged to 43 O serogroups and 77 O:H serotypes, 60% were of one of the 10 serogroups O2, O8, O15, O54, O84, O101, O141, O147, O149 and O157, and 60% belonged to only 10 serotypes (O8:H-, O54:H-, O84:H7, O101:H-, O141:H-, O141:H4, O147:H-, O149:H10, O163:H-, and ONT:H-). PCR showed that 79% of 220 isolates carried genes for at least one of the virulence factors tested. The gene encoding for EAST1 was the most prevalent (65%) followed by those encoding for STb (49%), LT (42%), STa (13%), and Stx2e (4%). Eighty-three (38%) of the 220 E. coli isolates carried the gene for F4 (K88), whereas genes for F18, F5 (K99), F41, F6 (P987), F17, and intimin (eae) were detected in 9%, 3%, 3%, 3%, 1%, and 3%, respectively. Seropathotype O149:H10:F4:LT/STb/EAST1 (70 isolates) was the most common, representing 32% of isolates. Pulsed-field gel electrophoresis (PFGE) analysis with XbaI of 15 O149:H10 representative isolates from diarrhoeic piglets distinguished 14 types. The 15 isolates exhibited a wide variability of distinct restriction patterns though all belonged to the same serotype (O149:H10), and all but one showed identical virulence determinants (F4, LT, STb, and EAST1). Among 30 isolates from healthy piglets only two virulence genes were detected: EAST1 (26%) and eae (17%). In total, 12 isolates were positives for the eae gene: five isolates had intimin beta1, four possessed intimin theta and three showed intimin type xiB. This is believed to be the first study describing the presence of intimin type xiB in E. coli of porcine origin.

Histologic Assessment of Donor Kidneys and Graft Outcome: Multivariate Analyses

We performed a multivariate analysis to evaluate the importance of histologic parameters in donor kidney biopsies as predictors of graft outcome.

METHODS

Wedge protocol biopsies from a single center were analyzed for glomerulosclerosis (GS), interstitial fibrosis (IF), tubular atrophy (TA), arteriosclerosis (AS), and arteriolar hyalinosis (AH). Alterations were quantified as percentage (GS, IF) or semiquantified according to Banff criteria (IF, TA, AS, AH). We calculated creatinine clearance (CrCl) at 1, 2, and 3 years posttransplant. Donor data included age, gender, and type: non-heart-beating donor or brain dead donors. Recipient data included age, gender, cold ischemia time, number of HLA mismatches, peak level of the panel reactive antibody (PRA), number of acute rejection episodes (ARE), and presence or absence of cytomegalovirus (CMV) disease. Univariate and multivariate analyses were performed. Follow-up range was 1 to 4.2 years.

RESULTS

GS, IF, TA, and AH were associated with graft survival in the multivariate analysis. The histologic parameters were associated with CrCl at several posttransplant time intervals, but the significance of association was lost in the multivariate analysis. Donor age showed a better correlation with graft function. In the univariate analyses adjusting for donor age, only IF and AH were associated with graft function.

CONCLUSIONS

Histologic parameters showed a modest association with graft function. In our study, donor age is the better predictor of graft function. IF and AH may be similar to or better than GS as predictors of graft outcome.