Improving quality of care and clinical outcomes for rectal cancer through clinical audits in a multicentre cancer care organisation.

INTRODUCTION: Colorectal cancer treatment requires a complex, multidisciplinary approach. Because of the potential variability, monitoring through clinical audits is advisable. This study assesses the effects of a quality improvement action plan in patients with locally advanced rectal cancer and treated with radiotherapy. METHODS: Comparative, multicentre study in two cohorts of 120 patients each, selected randomly from patients diagnosed with rectal cancer who had initiated radiotherapy with a curative intent. Based on the results from a baseline clinical audit in 2013, a quality improvement action plan was designed and implemented; a second audit in 2017 evaluated its impact. RESULTS: Standardised information was present on 77.5% of the magnetic resonance imaging (MRI) staging reports. Treatment strategies were similar in all three study centres. Of the patients whose treatment was interrupted, just 9.7% received a compensation dose. There was an increase in MRI re-staging from 32.5 to 61.5%, and a significant decrease in unreported circumferential resection margins following neoadjuvant therapy (ypCRM), from 34.5 to 5.6% (p <  0.001). CONCLUSIONS: The comparison between two clinical audits showed improvements in neoadjuvant radiotherapy in rectal cancer patients. Some indicators reveal areas in need of additional efforts, for example to reduce the overall treatment time.

Inhibition of cytotoxicity of Shiga toxin of Escherichia coli O157:H7 on vero cells by Prosopis alba Griseb (Fabaceae) and Ziziphus mistol Griseb (Rhamnaceae) extracts.

The capacity of Prosopis alba Griseb. and Ziziphus mistol Griseb. fruit extracts to inhibit the toxic action of Shiga toxin (Stx) was investigated. Purification of Stx from Escherichia coli O157:H7 was performed by saline precipitation and affinity chromatography using a column with globotriaosylceramide, while the fruits were subjected to ethanolic or aqueous extractions. The protective action of both fruits was determined by pre-, co-, and postincubation of one 50% cytotoxic dose per ml of Stx with different concentrations of ethanolic and aqueous extracts in confluent monolayers of Vero cells for 72 h at 37°C (5% CO2). The inhibition of the cytotoxic effect of Stx by fruit extracts was determined by the neutral red vital staining technique. The extraction of the polyphenols and flavonoids was effective, and more polyphenols per milligram of dissolved solids were obtained from P. alba than from Z. mistol. However, there were more flavonoids in Z. mistol than in P. alba. Components of both fruits increased the viability of cells treated with Stx when the extracts were preincubated with Stx for 1 h before being applied to the cell cultures, with the ethanolic extract of P. alba showing 95% cell viability at a concentration of 2.45 mg/ml. The extracts were less effective in protecting cells when Stx, extracts, and cells were coincubated together without a previous incubation of Stx; only the concentrations of 19.46 mg/ml for the P. alba aqueous extract and 3.75 mg/ml for the Z. mistol ethanolic extract resulted in the inhibition of cytotoxicity, with 52 and 56% cell viability occurring, respectively. Investigation into this difference in the protection of cells indicated that the protein molecule of Stx suffered degradation to advanced oxidative protein products during preincubation with extracts, principally with P. alba, which exhibited a greater amount of nonflavonoid polyphenols than Z. mistol. The prooxidant action on Stx favored the cells and enhanced the protective action of both fruits.

Increased advanced oxidation of protein products and enhanced total antioxidant capacity in plasma by action of toxins of Escherichia coli STEC.

Shiga toxin (Stx) and hemolysin (Hly) of Escherichia coli O157:H7 produced an increase of reactive oxygen species (ROS) in normal human blood. In vitro assays showed that stimuli of ROS with these toxins oxidized proteins to carbonyls in plasma and raised the degradation of oxidized macromolecules, with the AOPP/carbonyl relationship also increasing. The oxidative stress generated by toxins during the Hemolytic Uremic Syndrome (HUS) produced oxidation of blood proteins with a rise in advanced oxidation protein products (AOPP) in children with HUS. There was a response from the antioxidant system in these patients, evaluated through the determination of the total antioxidant capacity of plasma by the Ferric Reducing Antioxidant Power (FRAP), which reduced the stimuli of ROS during in vitro incubation with Stx or Hly. The application of natural antioxidants was sufficient to reduce in vitro the oxidative stress provoked by both toxins in blood.

Carcinoma de células fusiformes tipo “fibromatosis-like”: una variante inusual de carcinoma metaplásico de mama asociado a carcinoma ductal / No disponible

El carcinoma de células fusiformes tipo fibromatosis-like esuna variante del carcinoma metaplásico, que ha sido reconocidorecientemente como una entidad distinta e independiente del restode los tumores metaplásicos, que recuerda a la fibromatosis yse caracteriza por ser un tumor de bajo grado, con mejor pronósticoy tendencia a la recidiva local. Presentamos un caso de unapaciente de 71 años con un carcinoma tipo fibromatosis-likeasociado a un carcinoma ductal de la mama. La histología revelóun tumor de células fusiformes simulando una fibromatosis, dondese puede identificar un componente epitelial en forma de carcinomaductal o intraductal en continuidad con el componente deaspecto fusiforme. Inmunohistoquímicamente presentó positividadfocal para marcadores epiteliales y mioepiteliales como citoqueratinasy expresión de marcadores mesenquimales como vimentina.El diagnóstico exacto puede presentar dificultad tantoradiológica como anatomopatológica y plantea el diagnóstico diferencialcon lesiones benignas como fibromatosis, fascitis nodularo malignas como sarcomas. El comportamiento y pronósticono ha sido del todo aclarado aunque se ha visto que es un tumorque se caracteriza por un alto riesgo de recidiva, bajo potencialpara metastatizar en ganglios linfáticos regionales pero con capacidadpara producir metástasis a distancia y por tanto, debería sertratado en consecuencia(AU)

Fibromatosis-like spindle cell carcinoma of the breast is avariant of metaplastic carcinoma that has recently been recognizedas a different entity because of its resemblance to fibromatosisand similar propensity for local recurrence. We presenta case of 71- year-old lady with a fibromatosis-like carcinomaassociated with ductal carcinoma of the breast. Finalhistology revealed a tumor with predominant spindle cells in acollagenous background, simulating a fibromatosis. Inmunohistochemistryshowed focal positivity of ephithelial and myoephitelialmarkers as citokeratins and expression of mesenchymalmarker as vimentin in the tumor. This tumor can posediagnostic difficulty radiologic as histopathology and the differentialdiagnosis includes both benign and malignant spindlecell breast lesions as a fibromatosis, nodule fascitis or sarcomas.The behaviour and prognosis have not been well clarifiedalthough there seems to have high risk of local recurrence, lowpotential to metastasize to regional lymph nodes and potentialfor distant metastasis and should be treated accordingly(AU)

Comparison of oxidative stress induced by ciprofloxacin and pyoverdin in bacteria and in leukocytes to evaluate toxicity.

Oxidative stress induced by ciprofloxacin and pyoverdin, a leukotoxic pigment, was studied by comparing their effect in bacteria and leukocytes. Chemiluminescence (CL) assays with lucigenin or luminol were adapted to measure the stimuli of superoxide anion (O2 -) and other reactive species of oxygen (ROS) in bacteria. Ciprofloxacin principally induced the production of O2 - in the three species studied: Staphylococcus aureus, Enterococcus faecalis and Escherichia coli. Lucigenin CL assay showed high oxidative stress in S. aureus due to its low superoxide dismutase (SOD) activity, whereas E. coli exhibited important SOD activity, responsible for little production of O2 - in absence or presence of ciprofloxacin. Reduction of nitroblue of tetrazolium (NBT) was applied. This assay indicated that there was higher oxidative stress in S. aureus and E. faecalis than in E. coli. The comparison of oxidative stress generated in bacteria and leukocytes was used to check the selective toxicity of ciprofloxacin in comparison with pyoverdin. Ciprofloxacin did not generate significant stimuli of O2 - in neutrophils, while pyoverdin duplicated the production of O2 -. CL and NBT were useful to study the leukotoxicity of ciprofloxacin. Oxidative stress caused by the antibiotic and the leukotoxic pigment was similar in bacteria.

Selection of bacteriocin producer strains of lactic acid bacteria from a dairy environment.

Two strains showing bacteriocin production were selected from a total of 206 lactic acid bacteria isolated from samples of milk, milk serum, whey and homemade cheeses in Southern Cordoba, Argentina. This property was detected by means of well diffusion assays. The strains were identified as Enterococcus hirae and Enterococcus durans. The protein nature of those substances was proved by showing their sensitivity to type IV and XXV proteases, papaine, trypsin, pepsin and K proteinase. The bacteriocins inhibited the growth of Listeria monocytogenes, Bacillus cereus, Clostridium perfringes and two strains of Staphylococcus aureus, an A-enterotoxin and a B-enterotoxin producers. All of these bacteria are common pathogens usually associated with food borne diseases (ETA). These lactic acid bacteria or their bacteriocins could be suitable candidates for food preservation and specially useful in the our regional dairy industry.

Leukotoxicity of pyoverdin, production of reactive oxygen species, and effect of UV radiation.

Pyoverdin was purified by solvent extraction, gel filtration, and ionic exchange chromatography. Assays of cytotoxic of pyoverdin were done with human leukocytes and macrophages from the peritoneum of mice. Both cell quantities showed a significant reduction. Death was followed by lysis in a dose-dependent form. The mechanism of action of pyoverdin involved the stimulation of reactive oxygen species (ROS) measured by Nitroblue Tetrazolium (NBT) reaction and chemiluminescence (CL). UV radiation at 368 nm increased the leukotoxicity; expositions of 5 min were enough to photostimulate the effect of pyoverdin on cellular oxydative metabolism, which increased between 35.4 and 53.2%. Genestein, an inhibitor of tyrosine kinases, counteracted the ROS stimuli of pyoverdin, suggesting endocytic mechanism of action for this pigment. The little chloroquine interference on oxydative stress indicated that intraphagosomal pH and the stimuli of reactive nitrogen intermediaries (RNI) seem to be of less importance than ROS in pyoverdin action on leukocytes.

Conservation in probiotic preparations of Lactobacillus with inhibitory capacity on other species.

Strains of Lactobacillus isolated from dairy products and genital tract competed with Candida albicans through a membrane of 12000 dalton cut-off. This inhibition was due to hydrogen peroxide and was trypsin-stable, heat-sensitive and antagonized by catalase. Lactobacillus coming from "starters" showed antimicrobial activity against fungus isolated in a yogurt factory. Penicillium, Alternaria, Phialophora, Microsporum and Candida spp. were inhibited when 10(2) spores were inoculated in the assay. No inhibition was observed with 10(5) spores. Besides, one of 21 Lactobacillus strains isolated from the vaginas of healthy women inhibited pathogenic bacteria by means a bacteriocin trypsin-sensitive, heat-stable and retained by dialysis membrane. Tablets for future probiotic use were prepared and the viability of bacteria was assayed using media with different compositions. Pharmaceutical preparations with polyethyleneglycol was the best formulation for the Lactobacillus viability, the counts remained between 10(7) and 10(6) cfu/tablet for up to 1 year.

Preoperative induction chemotherapy followed by concurrent chemoradiotherapy in advanced carcinoma of the oral cavity and oropharynx.

BACKGROUND: Combined modality therapy plays a central role in the management of advanced head and neck tumors. The objective of our Phase II study was to determine the feasibility, toxicity, and clinical and pathologic response of preoperative induction chemotherapy, followed by concurrent chemoradiotherapy in patients with Stage III or IV squamous cell carcinoma according to the American Joint Committee on Cancer Staging of the oral cavity and oropharynx with no distant metastases. METHODS: After staging, 62 patients with locally advanced carcinoma of the oral cavity and oropharynx were treated preoperatively with chemotherapy (1 cycle of cisplatin and 5-fluorouracil [P-5FU]) followed by concurrent chemoradiotherapy (3 cycles of P-5FU combined with radiotherapy, 60 grays [Gy] given in 33 fractions of 1.8 Gy). After evaluation, patients underwent surgery either as a diagnostic (biopsy) or therapeutic procedure (resection of the primary tumor and/or the neck). Surgery was performed with the intent to spare organ function. RESULTS: Grade 3-4 mucositis was observed in 37 patients (59%). Overall clinical response was obtained in 87%, and the complete clinical response rate was 50%. Surgery was performed in 53 patients, 50 at the primary tumor site (11 biopsies, 14 marginal excisions, and 25 wide excision) and 46 patients had neck dissection. Pathologic complete remission was observed in 29 patients (46%). After a median follow-up of 39 months, locoregional control rate was 76%, estimated 3-year disease free survival rate was 73% (+/- 4%), and estimated 3-year overall survival rate was 76% (+/- 4%). CONCLUSIONS: This intensive multimodality treatment is feasible, and toxicity is significant but tolerable. The treatment results appear promising and durable. Organ-preserving surgery can be performed in many patients.

Elevation of alanine amino transferase and aspartate amino transferase produced by pyoverdin, a photolabile pigment of Pseudomonas fluorescens.

The effect of three forms pyoverdin on mouse liver was studied. Significant increases of alanine amino transferase (ALT) and aspartate amino transferase (AST) were obtained in mice after ingestion of water with forms A and C. The effect on liver was more evident with A than with C. Pyoverdin was purified by means of salt saturation, solvent extractions and ion-exchange chromatography. Fluorescent peaks obtained in the presence of light were different from those eluted under dark conditions. The relative amounts of pyoverdin A, B and C varied when dark purification procedure was employed. Form A decreased while C increased in the absence of light. Optimum conditions for C were in the dark without iron. When C was exposed to light, it changed to form A. Fast Atom Bombardment (FAB) mass spectrometry of pyoverdin form C gave a form at M+ = 1324 m.u., which is 9 m.u. less than pyoverdin purified in the presence of light. The results suggest that light can influence pyoverdin stability and toxicity.

Antibiotic activity of isoxazolylnaphthoquinone imines on mice infected with Staphylococcus aureus.

The antibiotic activity of new synthetic isoxazolylnaphthoquinone imines was studied. Pseudomonas aeruginosa ATCC 27853 and Escherichia coli ATCC 25922 were resistant to the four compounds studied (MIC > 128 micrograms ml-1), but Staphylococcus aureus ATCC 25923, ATCC 29213 and 30 clinical isolates of Staph. aureus were inhibited by 2-hydroxy-N-(3,4-dimethyl-5-isoxazolyl)-1,4-naphthoquinone-4-imine (I). This compound diminished bloodstream infection of mice injected i.m. with Staph. aureus; septicaemia decayed significantly when I was applied at the beginning of the infection while when I was given 3 d after bacterial challenge, a significant protection was afforded. Bactericidal activity in serum increased during the 5 h after I was administered i.p. The acetyl derivative of I had a high MIC but when inoculated orally in mice decreased the Staph. aureus counts in circulation. This protection occurred only when the schedule of administration started close to the bacterial challenge. Antibiotic activity in vivo may be associated with in vitro effects.

Staphylococcal protease assay with dye hide powder, elastin, collagen and udder extract.

Colorimetric determinations of proteolytic activity were performed to measure the effects on dye protean substrates including tissue powders. The substrates were assayed with 98 strains obtained from the milk of cows with mastitis. Trypsin was employed as positive control and it verified the susceptibility of the method. Enzymatic activity was estimated in trypsin units per milliliter of incubation mixture. The percentages of strains active on specific proteins were 47.8% for elastin, 61.6% for collagen and when hide powder and udder extract were used as dye substrates, the proteolytic staphylococci were 76.5 and 92.4% respectively. There was no significant difference in hydrolytic activity on proteins between coagulase positive and coagulase negative cocci.

Klebocin activity of Klebsiella pneumoniae strains and its heterologous effect on Staphylococcus sp.

Thirty six Klebsiella pneumoniae strains were assayed in a test to determine bacterial interference; two of them had bacteriocinic effects on homologous species, strains 6 and 150 inhibited sensitive K. pneumoniae and they also acted on positive and negative Staphylococci coagulase. All cocci were sensitive to the bacteriocinogenic K. pneumoniae and none of the non-bacteriocinogenic strains inhibited them. Klebocin with homologous activity on K. pneumoniae seemed to be undistinguishable from the compound with heterologous action on Staphylococci in the aspects that were characterized in this work; both were heat labile to the same degree; optimum pH was 7, acidity decreased klebocin activity more intensely than alkaline pH. The antagonistic substance was not produced in the synthetic medium employed and was developed in tryptic soy, nutrient agar, brain heart agar and blood agar; tryptone-beef extract agar complex medium neither permitted the homologous activity nor allowed the interference on Staphylococci. The compound (or compounds) responsible for homologous antimicrobial effect had a low molecular weight as demonstrated by the fact that it pierces a dialysis membrane with molecular weight of 10,000 D cut-offs. Ethidium bromide treatment of strains 6 and 150 produced five strains without bacteriocinic activity which simultaneously lost their homologous and heterologous inhibitory capacity.

Molecular weight determination and partial characterization of Klebsiella pneumoniae hemolysins.

Two thiol-activated Klebsiella pneumoniae hemolysins were purified from growth media by means of salt precipitation, gel filtration, ion-exchange chromatography, and polyacrylamide gel electrophoresis. The hemolysins peaks coincided with the protein and glycoprotein peaks as determined by chromatography and electrophoresis. The molecular weights, estimated by gel filtration, were 8400 and 19,000; by sodium dodecyl sulfate--polyacrylamide gel electrophoresis, the values were calculated as 15,500 and 27,000. The electrophoretic bands were best detected by the periodic acid--Schiff method. Reduction of the disulfide linkages did not cause the originally larger molecule to break into 8400 and 19,000 hemolysins. However, trypsin treatment cleaved the 19,000 hemolysin into an active moiety, with an electrophoretic migration similar to the 8400 hemolysin. A naturally occurring proteolytic activity was investigated using pepstatin and antipain. When the trypsin inhibitor was added to the system, the hemolytic activity was detected only in the 19,000 hemolysin and the smaller hemolysin was absent.

A thiol-activated hemolysin in gram-negative bacteria.

An investigation of Klebsiella pneumoniae hemolytic activity was carried out. Strains isolated from different infected specimens were hemolytic in tryptic soy agar with rabbit blood; incubation at 4 degrees C enhanced the hemolysis. There was no evident red blood cell lysis in plates with human, sheep, mouse, and chicken erythrocytes. The culture in tryptic soy broth, its supernatant and bacterial lysate did produce evident hemolysis of rabbit red blood cells when they were preincubated with 2-mercaptoethanol. Klebsiella pneumoniae hemolysin showed the Arrhenius effect, while temperatures over 60 degrees C for 10 min reduced the activity of crude hemolysin to zero; purified hemolysin, however, was heat stable. Two hemolysins active on rabbit red blood cells were purified and both shared several properties. This work represents the initial description of a thiol-activated hemolysin in Gram-negative bacteria.

Primary isolation of Trypanosoma cruzi by hemoculture: influence of glucose concentration.

Isolation of Trypanosoma cruzi in hemoculture was done in media with different glucose concentrations. The three strains studied developed into epimastigotes 2 weeks after seeding in media with less than 4.5 mM hexose. Inhibition of growth of trypanosomes in media containing a greater amount of glucose was not caused by the higher osmotic pressures. Cultures containing more than 4.5 mM glucose showed a greater depletion of pH and higher lactic acid production than did those with lower concentrations, resulting in damage to amastigote clusters or to initial epimastigote development. The maximum recommended level of glucose in the culture medium is determined by the detrimental acidification resulting from excessive quantities.

Infeccion natural de Akodon dolores,Thomas, 1916 (Rodentia, Cricetidae) por el Trypanosoma cruzi. / Natural infection of Akodon dolores,Thomas,1916 (Rodentia, Cricetidae) by Trypanosoma cruzi

El estudio morfobiometrico y biologico de tres cepas de tripanosomas de una poblacion de Akodon dolores de la zona periurbana del municipio de Las Higueras, provincia de Cordoba, Argentina, demostro que se trataba de T. cruzi. Como el 15% de 134 A. dolores examinados en la zona habia demostrado tripanosomas cruziformes, se concluye que este roedor e sun reservorio frecuente del parasito.El A. dolores es la especie numericamente dominante en la comunidad de roedores que vive en los habitats de mayor estabilidad en la region. Debe investigarse el ciclo de transmision silvestre asi como su relacion con el domiciliario en esta zona de baja endemicidad de enfermedad de Chagas en el hombre

[Primary isolation of Trypanosoma cruzi using hemoculture: effect of media composition on epimastigote differentiation]. / Aislamiento primario de Trypanosoma cruzi por hemocultivo: efecto de la composición del medio en la diferenciación a epimastigote.

It was investigated the modifications of culture medium which facilitated the differentiation of blood tripomastigotes of Trypanosoma cruzi to epimastigotes and its further reproduction. Trypanosomas were obtained "in vitro" from country rodents with parasites, caught in Las Higueras Municipality, Río Cuarto Department. They were differentiated and developed faster in mediums poorer in nutrients (N.N.N. and Tobie) than in enriched ones, generally used to mantain epimastigotes in culture (LIT and Medium Base). Different mediums were tested: a) Novy and Mc Neal medium modified by Nicole (N.N.N.); b) N.N.N. medium modified by the addition of glucose (10 g/l); c) Tobie medium with different mediums as liquid phase; d) Tobie medium modified by the addition of glucose (10 g/l); e) Warren medium; f) Warren medium modified by the addition of glucose (10 g/l); g) LIT medium; h) Medium Base (M.B.); i) 16 mediums obtained from M.B. modified by changing only one of its components, either quantitative or quantitatively, so that the difference with the original one was in a sole component. All mediums were assayed with blood of albino BALB/c mice infected with T. cruzi: Tulahuén strain and two wild strains isolated from country mice. To observe the effect on results, certain working conditions were changed: a) cultivated tripomastigotes density; b) blood from different rabbits, to enrich the cultures; c) trademark of each component used in medium preparations; d) bleeding of infected mice in different days post injection; e) mediums in liquid state or diphasic. These technical modifications did not alter the results. Only glucose proved to influence the differentiation to epimastigote.(ABSTRACT TRUNCATED AT 250 WORDS)