ABSTRACT
Aims To investigate the psychological care provided to children and young adolescents with cancer and their families within the National Children's Cancer Service (NCCS), Ireland, in respect of the national and international standards of care. Methods A retrospective audit of 316 referrals made over 32 months by the NCCS to the psychology service in malignant haematology and oncology was performed. Results The audit revealed that out of 316 patients, a yearly average of 189 (50%) of urgently referred patients received psychological support within the NCCS between January 2013 and August 2016. Furthermore only 20 (22%) undergoing haematopoietic stem cell transplantation (HSCT), 14 (22%) referred to the paediatric palliative care team, and 84 (62%) of teenage patients received psychological input during this timeframe. Conclusion The audit revealed that the current psychology service provision is failing to meet the international standards of care. Due to the data provided by this audit, in conjunction with a clinical risk assessment of the service, funds for the post of principal psychologist have been secured. Further psychology posts (HSCT, late-effects and neuropsychology), and development of the psycho-oncology model of care are required to ensure equality of access and evidence-based psychological care for all children with cancer.
Subject(s)
Neoplasms , Psycho-Oncology , Adolescent , Humans , Medical Oncology , Neoplasms/therapy , Referral and Consultation , Retrospective StudiesABSTRACT
The reduction and oxidation of epitaxial Fe3O4 films grown by reactive deposition on a Fe-p(1 × 1)O surface have been investigated by means of Auger electron spectroscopy (AES), low energy electron diffraction (LEED) and scanning tunneling microcopy (STM). The as-grown iron oxide samples display a square LEED pattern with a lattice constant compatible with a p(1 × 1) bulk terminated Fe3O4(001) surface. STM topographic images of Fe3O4 are characterized by atomically flat terraces separated by highly oriented steps running along the (010) and (100) crystallographic directions of the substrate. Upon annealing at 800 K in an ultra-high vacuum, AES reveals that magnetite transforms to FeO. The sample exposes the (001) surface of the rock salt structure, with a lattice parameter close to that of bulk wüstite. The Fe3O4 phase can be recovered by oxidation at 10-6 mbar of molecular oxygen.
ABSTRACT
Aim Rhabdomyosarcoma (RMS) is the most common malignant soft tissue tumour of childhood. We present the case of a late relapse of RMS to the leptomeninges after 15 years. Methods A 20 year old male presented with a 3 week history of headaches and nausea. He previously had RMS of his right ear diagnosed at age 5 years which was treated with concurrent chemoradiotherapy. An MRI Brain and Spine confirmed extensive leptomeningeal disease and CSF analysis confirmed the presence of recurrent embryonal RMS. Results He completed two cycles of cyclophosphamide and topotecan followed by 45Gy/25Fr of craniospinal radiotherapy. Conclusion Late relapses beyond five years can be seen in up to 9% of patients, however very late recurrences (>10 years) are exceedingly rare. Molecular based methods such as gene expression profiling can aid risk stratification and survivorship clinics may become increasingly useful in following patients with high risk features.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Chemoradiotherapy/methods , Ear Neoplasms/therapy , Meningeal Neoplasms/therapy , Neoplasm Recurrence, Local/therapy , Rare Diseases , Rhabdomyosarcoma, Embryonal/therapy , Adult , Child, Preschool , Cyclophosphamide/administration & dosage , Humans , Male , Radiotherapy Dosage , Time Factors , Topotecan/administration & dosage , Treatment Outcome , Young AdultABSTRACT
Summary: Anakinra, one of the novel biological agents, is a recombinant human IL-1 receptor antagonist. It is preferred as an alternative drug for familial Mediterranean fever cases where colchicine is not sufficient or cannot be used due to its side effects. Like all other biologics, hypersensitivity reactions to anakinra are quite rare. This is the first case which was successfully desensitized with anakinra after a severe immediate-type hypersensitivity reaction. We report a case of WDEIA in an asthmatic boy admitted to our Unit with suspected mushroom acute toxicity. The symptoms occurred during a gym session, approximately 2 hours after the ingestion of a meal based on pasta and cooked mushroom found in the family's garden. Acute toxicity due to mushroom ingestion was then excluded. Triptase serum levels resulted elevated in acute phase and normal after 24 hours. Food specific IgE showed a sensitization to lipid transfer protein Pru p 3 and to Tri a 14. This case highlights that WDEIA is underdiagnosed, especially when patients are firstly visited in Emergency Unit. Moreover, Tri a 14 is seldom described as responsible for WDEIA, compared to omega 5 gliadin.
Subject(s)
Agaricales/immunology , Anaphylaxis/immunology , Antigens, Plant/immunology , Carrier Proteins/immunology , Exercise , Wheat Hypersensitivity/immunology , Asthma, Exercise-Induced/immunology , Child , Humans , Immunoglobulin E/blood , Intracellular Signaling Peptides and Proteins , Male , Skin Tests , Triticum/immunologyABSTRACT
BACKGROUND: Proton therapy (PT) is a radiotherapy treatment modality that uses protons, rather than conventional photons. PT is often used in paediatric oncology due to its reported capability to reduce acute and late adverse treatment effects. As PT is unavailable in Ireland, patients are referred abroad for treatment. AIMS: To: (1) produce a descriptive study of Irish children referred abroad for PT, and (2) discuss the case for PT in general. METHODS: A retrospective review of all children referred for PT before October 2015 was performed. Information was gathered regarding demographics, diagnosis, referral timeline, adverse effects attributable to PT, current status and cost. A review of the relevant literature was performed. RESULTS: Seventeen children treated in Ireland have been referred abroad for PT. The largest number was in the 0-4 year old group. At initial diagnosis the median age was 4.8 years. The average cost per child was 37,312. Two patients suffered disease relapse. Four have encountered PT-related adverse effects. CONCLUSION: Despite the fact that >100,000 patients worldwide have been treated with PT, the level of published evidence to support superiority over conventional treatment remains low. It is debated that randomised control trials in this area would be inconsistent with the principle of clinical equipoise. In contrast, there is a call for level 1 evidence to justify drastic changes in patient care, particularly in light of recent reports of unexpected toxicities. In time, careful evaluation, follow-up and clinical trials will likely support the preferential use of PT in children.
Subject(s)
Medical Oncology/methods , Proton Therapy/methods , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Ireland , Male , Retrospective StudiesABSTRACT
BACKGROUND: Four international study groups undertook a large study in resectable osteosarcoma, which included two randomised controlled trials, to determine the effect on survival of changing post-operative chemotherapy based on histological response. PATIENTS AND METHODS: Patients with resectable osteosarcoma aged ≤40 years were treated with the MAP regimen, comprising pre-operatively of two 5-week cycles of cisplatin 120 mg/m(2), doxorubicin 75 mg/m(2), methotrexate 12 g/m(2) × 2 (MAP) and post-operatively two further cycles of MAP and two cycles of just MA. Patients were randomised after surgery. Those with ≥10% viable tumour in the resected specimen received MAP or MAP with ifosfamide and etoposide. Those with <10% viable tumour were allocated to MAP or MAP followed by pegylated interferon. Longitudinal evaluation of quality of life was undertaken. RESULTS: Recruitment was completed to the largest osteosarcoma study to date in 75 months. Commencing March 2005, 2260 patients were registered from 326 centres across 17 countries. About 1334 of 2260 registered patients (59%) were randomised. Pre-operative chemotherapy was completed according to protocol in 94%. Grade 3-4 neutropenia affected 83% of cycles and 59% were complicated by infection. There were three (0.13%) deaths related to pre-operative chemotherapy. At definitive surgery, 50% of patients had at least 90% necrosis in the resected specimen. CONCLUSIONS: New models of collaboration are required to successfully conduct trials to improve outcomes of patients with rare cancers; EURAMOS-1 demonstrates achievability. Considerable regulatory, financial and operational challenges must be overcome to develop similar studies in the future. The trial is registered as NCT00134030 and ISRCTN 67613327.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bone Neoplasms/drug therapy , Osteosarcoma/drug therapy , Adolescent , Bone Neoplasms/surgery , Child , Cisplatin/administration & dosage , Cisplatin/adverse effects , Combined Modality Therapy , Doxorubicin/administration & dosage , Doxorubicin/adverse effects , Etoposide/administration & dosage , Etoposide/adverse effects , Female , Humans , Ifosfamide/administration & dosage , Ifosfamide/adverse effects , Interferon-alpha/administration & dosage , Interferon-alpha/adverse effects , Male , Methotrexate/administration & dosage , Methotrexate/adverse effects , Neoadjuvant Therapy , Osteosarcoma/surgery , Polyethylene Glycols/administration & dosage , Polyethylene Glycols/adverse effects , Quality of Life , Research Design , Young AdultABSTRACT
Congenital-infantile fibrosarcoma is a rare entity with a five year survival rate of over 90%. Surgery is still the most common treatment modality with amputation often necessary. There have been reports supporting the use of neoadjuvant chemotherapy to debulk the tumour in an effort to facilitate limb sparing surgery. We report a case of a newborn who presented with a life threatening haemorrhage from a fibrosarcoma of the foot, successfully treated with Vincristine, Actinomycin and Cyclophosphamide (VAC) chemotherapy alone.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Fibrosarcoma/drug therapy , Limb Salvage/methods , Soft Tissue Neoplasms/drug therapy , Chemotherapy, Adjuvant/methods , Cyclophosphamide/administration & dosage , Dactinomycin/administration & dosage , Fibrosarcoma/congenital , Fibrosarcoma/diagnostic imaging , Foot/diagnostic imaging , Foot/pathology , Humans , Infant, Newborn , Radiography , Soft Tissue Neoplasms/congenital , Soft Tissue Neoplasms/diagnostic imaging , Treatment Outcome , Vincristine/administration & dosageSubject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bone Neoplasms/drug therapy , Keratoderma, Palmoplantar/etiology , Pachyonychia Congenita/complications , Sarcoma, Ewing/drug therapy , Adolescent , Bone Neoplasms/complications , Female , Humans , Remission, Spontaneous , Ribs , Sarcoma, Ewing/complicationsABSTRACT
AIMS: To isolate and characterize bacterial strains derived from Lactobacillus casei and Lactobacillus paracasei strains and resistant to phage MLC-A. METHODS AND RESULTS: Two of nine assayed strains rendered resistant mutants with recovery efficiencies of 83% (Lact. paracasei ATCC 27092) and 100% (Lact. casei ATCC 27139). DNA similarity coefficients (RAPD-PCR) confirmed that no significant genetic changes occurred while obtaining resistant mutants. Neither parent nor mutant strains spontaneously released phages. Phage-resistant mutants were tested against phages PL-1, J-1, A2 and MLC-A8. Lactobacillus casei ATCC 27092 mutants showed, overall, lower phage resistance than Lact. paracasei ATCC 27092 ones, but still higher than that of the parent strain. Lactobacillus paracasei ATCC 27092 mutants moderately adsorbed phage MLC-A only in calcium presence, although their parent strain successfully did it with or without calcium. Adsorption rates for Lact. casei ATCC 27139 and its mutants were highly influenced by calcium. Again, phage adsorption was higher on the original strain. CONCLUSIONS: Several isolates derived from two Lact. casei and Lact. paracasei strains showed resistance to phage MLC-A but also to other Lact. casei and Lact. paracasei phages. SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlights isolation of spontaneous bacteriophage-resistant mutants from Lact. casei and Lact. paracasei as a good choice for use in industrial rotation schemes.
Subject(s)
Bacteriophages/physiology , Lacticaseibacillus casei/isolation & purification , Lactobacillus/isolation & purification , Bacteriophage Typing , Calcium/metabolism , DNA, Bacterial/genetics , Lactobacillus/genetics , Lactobacillus/virology , Lacticaseibacillus casei/genetics , Lacticaseibacillus casei/virology , Mutation , Phenotype , Random Amplified Polymorphic DNA Technique , Virus InternalizationABSTRACT
AIMS: To evaluate the phage diversity in the environment of a dairy industry which manufactures a product fermented with a probiotic strain of Lactobacillus paracasei. METHODS AND RESULTS: Twenty-two Lact. paracasei phages were isolated from an industrial plant that manufactures a probiotic dairy product. Among them, six phages were selected based on restriction profiles, and two phages because of their notable thermal resistance during sample processing. Their morphology, host range, calcium dependency and thermal resistance were investigated. All phages belonged to the Siphoviridae family (B1 morphotype), were specific for Lact. casei and paracasei strains showing identical host spectrum, and only one phage was independent of calcium for completing its lytic cycle. Some of the phages showed an extraordinary thermal resistance and were protected by a commercial medium and milk. CONCLUSIONS: Phage diversity in a probiotic product manufacture was generated to a similar or greater extent than during traditional yogurt or cheese making. SIGNIFICANCE AND IMPACT OF THE STUDY: This work emphasizes probiotic phage infections as a new ecological situation beyond yogurt or cheese manufactures, where the balanced coexistence between phages and strains should be directed toward a favourable state, thus achieving a successful fermentation.
Subject(s)
Bacteriophages/isolation & purification , Dairying , Lactobacillus/virology , Apoptosis/drug effects , Bacteriophages/genetics , Bacteriophages/growth & development , Calcium/pharmacology , DNA, Viral/analysis , Electrophoresis, Agar Gel , Environmental Microbiology , Food Handling , Hot Temperature , Kinetics , Microscopy, Electron , Restriction Mapping , Sterilization/methodsABSTRACT
BACKGROUND: Cardiovascular magnetic resonance (CMR) by delayed enhancement (DE) enables visualisation of myocardial scarring, but no dedicated studies are available in thalassaemia major. OBJECTIVE: To investigate the prevalence, extent, clinical and instrumental correlates of myocardial fibrosis or necrosis by DE CMR in patients with thalassaemia major. PATIENTS: 115 Patients with thalassaemia major consecutively examined at an MRI laboratory. METHODS: DE images were acquired to quantify myocardial scarring. Myocardial iron overload was determined by multislice multiecho T2*. Cine images were obtained to evaluate biventricular function. RESULTS: DE areas were present in 28/115 patients (24%). The mean (SD) extent of DE was 3.9 (2.4)%. In 26 patients the location of fibrosis was not specific and patchy distribution was prevalent. Two patients showed transmural DE following coronary distribution. The DE group was significantly older than the no-DE group (31 (7.7) years vs 26 (7.7) years, p = 0.004). No significant relation with heart T2* values and biventricular function was found. A significant correlation was found between the presence of DE and changes in ECG (ECG abnormal in the DE group 22/28 patients and in the no-DE group 30/87 patients; chi(2) = 14.9; p<0.001). CONCLUSIONS: In patients with thalassaemia the significant presence of myocardial fibrosis/necrosis seems to be a time-dependent process correlating with cardiovascular risk factors and cardiac complications. Levels of HCV antibodies are significantly higher in the serum of patients with thalassaemia with myocardial fibrosis/necrosis. ECG changes showed a good accuracy in predicting myocardial scarring.
Subject(s)
Cicatrix/pathology , Myocardium/pathology , beta-Thalassemia/pathology , Adult , Female , Humans , Iron Overload/pathology , Magnetic Resonance Angiography/methods , Magnetic Resonance Imaging, Cine , Male , Necrosis/pathology , Retrospective StudiesABSTRACT
Several apparently idiopathic cases of so called 'senile chorea' have been recently redefined by the availability of brain MRI scan and the clinical introduction of genetic testing for Huntington's disease. Cases currently still regarded as idiopathic might yet be attributed to other medical conditions. Chorea as a unique manifestation of a primary antiphospholipid syndrome (PAPS) has so far been described only in young and middle-aged subjects. Here, we report a typical case of 'senile chorea' associated with PAPS, thus expanding the potential underlying etiologies and further narrowing the window of primary 'senile chorea'.
Subject(s)
Antiphospholipid Syndrome/complications , Chorea/diagnosis , Age of Onset , Aged , Anti-Dyskinesia Agents/therapeutic use , Antibodies, Antiphospholipid/blood , Anticonvulsants/therapeutic use , Antiphospholipid Syndrome/blood , Antiphospholipid Syndrome/diagnosis , Basal Ganglia/pathology , Carbamazepine/analogs & derivatives , Carbamazepine/therapeutic use , Chorea/drug therapy , Chorea/epidemiology , Chorea/etiology , Chorea/pathology , Diagnosis, Differential , Diazepam/therapeutic use , Epilepsy, Tonic-Clonic/etiology , Female , Haloperidol/therapeutic use , Humans , Huntington Disease/diagnosis , Magnetic Resonance Imaging , OxcarbazepineABSTRACT
Bacteriophage infections of starter lactic acid bacteria (LAB) pose a serious risk to the dairy industry. Nowadays, the expanding use of valuable Lactobacillus strains as probiotic starters determines an increase in the frequency of specific bacteriophage infections in dairy plants. This work describes a simple and rapid Polymerase Chain Reaction (PCR) method that detects and identifies bacteriophages infecting Lactobacillus casei/paracasei, the main bacterial species used as probiotic. Based on a highly conserved region of the NTP-binding genes belonging to the replication module of L. casei phages phiA2 and phiAT3 (the only two whose genomes are completely sequenced), a pair of primers was designed to generate a specific fragment. Furthermore, this PCR detection method proved to be a useful tool for monitoring and identifying L. casei/paracasei phages in industrial samples since specific PCR signals were obtained from phage contaminated milk (detection limit: 10(4) PFU/mL milk) and other commercial samples (fermented milks and cheese whey) that include L. casei/paracasei as probiotic starter (detection limit: 10(6) PFU/mL fermented milk). Since this method can detect the above phages in industrial samples and can be easily incorporated into dairy industry routines, it might be readily used to earmark contaminated milk for use in processes that do not involve susceptible starter organisms, or processes which involve phage-deactivating conditions.
Subject(s)
Bacteriophages/isolation & purification , Dairy Products/microbiology , Food Contamination/analysis , Lacticaseibacillus casei/virology , Milk/virology , Polymerase Chain Reaction/methods , Animals , Cattle , Colony Count, Microbial , Consumer Product Safety , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Humans , Milk/microbiology , Molecular Sequence Data , Probiotics , Risk Assessment , Sensitivity and Specificity , Sequence AlignmentABSTRACT
Metastases have been widely thought to arise from rare, selected, mutation-bearing cells in the primary tumor. Recently, however, it has been proposed that breast tumors are imprinted ab initio with metastatic ability. Thus, there is a debate over whether 'phenotypic' disease progression is really associated with 'molecular' progression. We profiled 26 matched primary breast tumors and lymph node metastases and identified 270 probesets that could discriminate between the two categories. We then used an independent cohort of breast tumors (81 samples) and unmatched distant metastases (32 samples) to validate and refine this list down to a 126-probeset list. A representative subset of these genes was subjected to analysis by in situ hybridization, on a third independent cohort (57 primary breast tumors and matched lymph node metastases). This not only confirmed the expression profile data, but also allowed us to establish the cellular origin of the signals. One-third of the analysed representative genes (4 of 11) were expressed by the epithelial component. The four epithelial genes alone were able to discriminate primary breast tumors from their metastases. Finally, engineered alterations in the expression of two of the epithelial genes (SERPINB5 and LTF) modified cell motility in vitro, in accordance with a possible causal role in metastasis. Our results show that breast cancer metastases are molecularly distinct from their primary tumors.
Subject(s)
Breast Neoplasms/genetics , Breast Neoplasms/pathology , Lymphatic Metastasis/genetics , Adult , Aged , Algorithms , Cell Movement/genetics , Cluster Analysis , Cohort Studies , Disease Progression , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Humans , Matched-Pair Analysis , Middle Aged , Oligonucleotide Array Sequence Analysis , Serpins/physiologyABSTRACT
Nonstarter lactic acid bacteria are the main uncontrolled factor in today's industrial cheese making and may be the cause of quality inconsistencies and defects in cheeses. In this context, adjunct cultures of selected lactobacilli from nonstarter lactic acid bacteria origin appear as the best alternative to indirectly control cheese biota. The objective of the present work was to study the technological properties of Lactobacillus strains isolated from cheese by in vitro and in situ assays. Milk acidification kinetics and proteolytic and acidifying activities were assessed, and peptide mapping of trichloroacetic acid 8% soluble fraction of milk cultures was performed by liquid chromatography. In addition, the tolerance to salts (NaCl and KCl) and the phage-resistance were investigated. Four strains were selected for testing as adjunct cultures in cheese making experiments at pilot plant scale. In in vitro assays, most strains acidified milk slowly and showed weak to moderate proteolytic activity. Fast strains decreased milk pH to 4.5 in 8 h, and continued acidification to 3.5 in 12 h or more. This group consisted mostly of Lactobacillus plantarum and Lactobacillus rhamnosus strains. Approximately one-third of the slow strains, which comprised mainly Lactobacillus casei, Lactobacillus fermentum, and Lactobacillus curvatus, were capable to grow when milk was supplemented with glucose and casein hydrolysate. Peptide maps were similar to those of lactic acid bacteria considered to have a moderate proteolytic activity. Most strains showed salt tolerance and resistance to specific phages. The Lactobacillus strains selected as adjunct cultures for cheese making experiments reached 10(8) cfu/g in soft cheeses at 7 d of ripening, whereas they reached 10(9) cfu/g in semihard cheeses after 15 d of ripening. In both cheese varieties, the adjunct culture population remained at high counts during all ripening, in some cases overcoming or equaling primary starter. Overall, proximate composition of cheeses with and without added lactobacilli did not differ; however, some of the tested strains continued acidifying during ripening, which was mainly noticed in soft cheeses and affected overall quality of the products. The lactobacilli strains with low acidifying activity showed appropriate technological characteristics for their use as adjunct cultures in soft and semihard cheeses.
Subject(s)
Cheese/microbiology , Food Microbiology , Lactobacillus/physiology , Animals , Argentina , Cheese/analysis , Cheese/standards , Humans , Hydrogen-Ion Concentration , Lactobacillus/classification , Lactobacillus/drug effects , Milk/chemistry , Potassium Chloride/pharmacology , Principal Component Analysis , Sodium Chloride/pharmacology , Streptococcus/physiology , Time Factors , Trichloroacetic Acid/chemistryABSTRACT
The capacity of three phosphates to interrupt the lytic cycle of four specific autochthonal bacteriophages of lactic acid bacteria used as starters was assayed. The phosphates used (polyphosphates A and B and sodium tripolyphosphate-high solubility [TAS]) were selected on the basis of their capacity to sequester divalent cations, which are involved in the lytic cycle of certain bacteriophages. The assays were performed in culture media (deMan Rogosa Sharpe and Elliker broths) and reconstituted (10%, wt/vol) commercial skim milk to which phosphates had been added at concentrations of 0.1, 0.3, and 0.5% (wt/vol). Phosphate TAS was the most inhibitory one, since it was able to inhibit the lytic cycle of all bacteriophages studied, in both broths and milk. In broth, polyphosphates A and B inhibited the lytic cycle of only two bacteriophages at the maximal concentration used (0.5%), whereas in milk, they were not capable of maintaining the same inhibitory effect.
Subject(s)
Bacteriophages/physiology , Calcium/metabolism , Disinfectants/pharmacology , Lactobacillus/virology , Phosphates/pharmacology , Animals , Bacteriophages/drug effects , Dose-Response Relationship, Drug , Humans , Kinetics , Lactobacillus/growth & development , Microbial Sensitivity Tests , MilkABSTRACT
Gastric carcinoma is one of the major causes of cancer mortality worldwide. Early detection results in excellent prognosis for patients with early cancer (EGC), whereas the prognosis of advanced cancer (AGC) patients remains poor. It is not clear whether EGC and AGC are molecularly distinct, and whether they represent progressive stages of the same tumor or different entities ab initio. Gene expression profiles of EGC and AGC were determined by Affymetrix technology and quantitative polymerase chain reaction. Representative regulated genes were further analysed by in situ hybridization (ISH) on tissue microarrays. Expression analysis allowed the identification of a signature that differentiates AGC from EGC. In addition, comparison with normal gastric mucosa indicated that the majority of alterations associated with EGC are retained in AGC, and that further expression changes mark the transition from EGC to AGC. Finally, ISH analysis showed that representative genes, differentially expressed in the invasive areas of EGC and AGC, are not differentially expressed in the non-invasive areas of the same tumors. Our data are more directly compatible with a progression model of gastric carcinogenesis, whereby EGC and AGC may represent different molecular stages of the same tumor. Finally, the identification of an AGC-specific signature might help devising novel therapeutic strategies for advanced gastric cancer.
Subject(s)
Biomarkers, Tumor/biosynthesis , Biomarkers, Tumor/genetics , Gene Expression Profiling , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , Cell Differentiation/genetics , Cell Proliferation , Disease Progression , Follow-Up Studies , Humans , Oligonucleotide Array Sequence Analysis , Severity of Illness Index , Stomach Neoplasms/classification , Stomach Neoplasms/metabolismABSTRACT
A new virulent bacteriophage (MLC-A) was recently isolated in Argentina from a probiotic dairy product containing a strain of Lactobacillus paracasei. Observation of the lysate with an electron microscope revealed bacteriophage particles with an icosahedral capsid of 57 +/- 2 nm; with a collar and a noncontractile tail of 156 +/- 3 nm terminating with a baseplate to which a tail fiber was attached. Therefore, phage MLC-A belongs to the Siphoviridae family. This phage was able to survive the pasteurization process and was resistant to alcohols and sodium hypochlorite (400 mg/kg). Only peracetic acid could inactivate high-titer suspensions of phages in a short time. The maximum rates of phage adsorption to its host cells were obtained at 30 degrees C with a pH between 5 and 7, and in the presence of calcium or magnesium ions. The host range of phage MLC-A encompassed L. paracasei and Lactobacillus casei strains, but it was not able to infect Lactobacillus rhamnosus or Lactobacillus gasseri strains. One-step growth kinetics of its lytic development revealed latent and burst periods of 30 and 135 min, respectively, with a burst size of about 69 +/- 4 plaque-forming units per infected cell. Phage MLC-A had a distinctive restriction profile when compared with the 2 well-studied Lactobacillus phages, PL-1 and J-1. The genome size of the MLC-A phage was estimated to be approximately 37 kb. This study presents the description of the first phage specific for L. paracasei isolated in Argentina. The isolation of phage MLC-A indicates that, beside lactic acid bacteria starters, probiotic cultures can also be sensitive to virulent phages in industrial processes.
Subject(s)
Bacteriophages/isolation & purification , Lactobacillus/virology , Adsorption , Alcohols/pharmacology , Argentina , Bacteriophages/growth & development , Bacteriophages/ultrastructure , Cations, Divalent/pharmacology , DNA, Viral/analysis , Dairy Products/microbiology , Dairy Products/virology , Fermentation , Food Handling/methods , Hot Temperature , Hydrogen-Ion Concentration , Microscopy, Electron , Peracetic Acid/pharmacology , Probiotics , Siphoviridae/growth & development , Siphoviridae/isolation & purification , Siphoviridae/ultrastructure , Sodium Hypochlorite/pharmacology , Viral Plaque AssayABSTRACT
AIM: To investigate the influence of several environmental factors on the viability and cell-adsorption for two Lactobacillus casei/paracasei bacteriophages (PL-1 and J-1). METHODS AND RESULTS: Both phages showed a remarkably high specificity of species, sharing similar host spectra. Two phages and four sensitive strains were used to conform five phage/strain systems. Each showed a particular behaviour (burst size: ranging from 32 to 160 PFU/infective centre; burst time: 120-240 min and latent time: 5-90 min). For both phages, the viability was not significantly affected from pH 4 to 11 (room temperature) and from pH 5 to 10 (37 degrees C). Adsorption rates were not influenced by calcium ions, but decreased after the thermal inactivation of cells. Adsorption rates were high between 0 and 50 degrees C with maximum values at 30 degrees C and pH 6. System PL-1/Lact. paracasei A showed noticeable differences in comparison with the others, being times required to reach 90% of adsorption of 4 h and lower than 45 min, respectively. CONCLUSIONS: The data obtained in this work demonstrated that environmental parameters can influence the viability and cell adsorption rates of Lact. casei/paracasei phages. The extent of this influence was phage dependent. SIGNIFICANCE AND IMPACT OF THE STUDY: This work contributes to the enlargement of the currently scarce knowledge of phages of probiotic bacteria.