Ayurveda panchakarma treatment success in a case of chronic spontaneous urticaria non-responding to conventional medicine-A case study.

This is a case study of a 34-year-old male patient of Chronic Spontaneous Urticaria (CSU) with severe generalised itching and rashes all over the body since 17 years. The patient has no significant relief with conventional antihistamine therapies, AST (Autologous serum therapy) and Omalizumab (OMA). He was clinically assessed and managed with Ayurvedic Panchakarma procedures like Snehapana(therapeutic administration of unctuous formulation like ghee, oil), Vamana, Virechana and internal medication in line of Seethapitta Chikitsa. The patient was asked to monitor hives and itching daily for one week using a validated weekly Urticaria Activity Score (UAS7) at the baseline, after Vamana, after Virechana and after follow up. The Quality of life was assessed at the baseline and after follow-up using Chronic Urticaria Quality of Life Questionnaire (CU-Q2oL). The assessment showed complete remission in disease activity and improvement in Quality of life as per the scores. The hematological and biochemical investigations reflect the safety and efficacy of Ayurveda in management of CSU.

Interaction effects of sunflower oil and aflatoxin at graded levels in diet on performance, serum and tissue biochemical profile, organ weights and immuneresponse in broiler chicken.

The dietary supplementation of fat has great potential in countering the toxic effects of aflatoxin (AF) in chickens, but the issue was less researched upon. An experiment was conducted to evaluate the response of broiler chickens to graded levels of AF B1 (0, 150 and 300 ppb) and sunflower oil (SFO) (0, 1.5 and 3.0%) in the diet in a 3 × 3 factorial manner to understand their interaction effects. A total of 360 broiler chickens divided into 9 equal groups were fed the diets during 0 to 35 days of age, and their response was evaluated in terms of performance, serum biochemical profile, organ weights, liver fat content and bone mineralization. Sunflower oil at 1.5% in diet countered (P ≤ 0.01) the adverse effects of 150 ppb AF on body weight, whereas at 300 ppb AF, such a response was seen at the higher level (3%) of SFO. Aflatoxin decreased (P ≤ 0.01) feed intake by 4 and 11% at 150 and 300 ppb concentration, respectively at 35 days of age, which was increased (P ≤ 0.01) with each incremental level of SFO supplementation (by 3.0 and 8.8%, respectively at 1.5 and 3%, respectively). Serum protein concentration increased (P ≤ 0.01) by SFO supplementation only at the higher concentration (300 ppb) of AF (by 42.4%), whereas total cholesterol and triglyceride concentration, and immune response to SRBC inoculation increased (P ≤ 0.01) with SFO at either level of AF (by 16.8, 18.7 and 75.6% at 1.5% SFO and 33.1, 36.9 and 94.2% at 3.0% SFO, respectively at 35 days of age). Weights of the liver, giblets, kidneys and pancreas increased (P ≤ 0.01) by 23.2, 14.7, 34.2 and 16.9%, respectively, and thymus weight decreased (P ≤ 0.04) by 25.4% with 300 ppb AF, and SFO at 3% in diet countered the effect on weight of the liver and giblets. Fat deposition in the liver increased (P ≤ 0.01) as the concentration of AF increased in diet (by 9.4 and 17.3%, respectively at 150 and 300 ppb AF), which was significantly (P ≤ 0.05) countered by SFO at 3% in diet. Tibia bone Ca content increased by 2.4% (P ≤ 0.01) with SFO supplementation in AF-fed chickens. It is concluded that dietary SFO supplementation countered the adverse effects of AF in broiler chicks in a dose-dependent manner, and higher level of oil (3% in diet) was required at the higher concentration of AF (300 ppb) in diet.

Effect of surfactant on quality and performance attributes of topical semisolids.

Surfactants are the most common inactive ingredients used in topical drug products. Surfactants in topical products play many functional roles such as emulsifiers, permeation enhancers, and solubilizers. This study was aimed to evaluate the influence of incremental change in the concentration of a surfactant (tween 80) on the quality attributes and performance of semisolid topical products. Four creams were prepared using metronidazole as a model drug using the same manufacturing protocol and similar composition except for the concentration of tween 80, which was increased by 5% w/w across SF1 to SF4. The quality attributes like globule size, pH, drying rate, and in-vitro permeation profile were characterized. The critical quality attributes did not differ significantly across the products. However, there was a significant difference in the permeation profile of the products. The permeation flux (Jmax) varied from SF1 to SF4 (51.25 ± 35.29 to 307.98 ± 138.89 ng/cm2/h, respectively). The reason for the difference in the performance of products despite having consistent quality attributes was investigated. One of the major reasons was found to be the difference in the time course of degree of saturation of drug during the evaporative metamorphosis. This study confirms that the time course of degree of saturation is one of the important quality attributes of the topical product that could influence bioavailability and performance of topical products.

Beyond Tympanomastoidectomy: A Review of Less Common Postoperative Temporal Bone CT Findings.

Postoperative temporal bone imaging after surgical procedures such as ossiculoplasty, tympanomastoidectomy, cochlear implantation, and vestibular schwannoma resection is often encountered in clinical neuroradiology practice. Less common otologic procedures can present diagnostic dilemmas, particularly if access to prior operative reports is not possible. Lack of familiarity with the less common surgical procedures and expected postoperative changes may render radiologic interpretation challenging. This review illustrates key imaging findings after surgery for Ménière disease, superior semicircular canal dehiscence, temporal encephalocele repairs, internal auditory canal decompression, active middle ear implants, jugular bulb and sigmoid sinus dehiscence repair, and petrous apicectomy.

Polymeric nanoparticles as a platform for permeability enhancement of class III drug amikacin.

Amikacin (A), a water soluble aminoglycoside antibiotic is commercially available for intravenous administration only. Present investigation is aimed at the development of poly-lactic-co-glycolic acid (PLGA) nanoparticles (A-NPs).1 for oral permeability enhancement of amikacin. The pharmaceutical attributes of the A-NPs revealed particle size, 260.3 ±â€¯2.05 nm, zeta potential, -12.9 ±â€¯1.12 mV and drug content, 40.10 ±â€¯1.87 µg/mg with spherical shape and smooth surface. In vitro antibacterial studies showed that the A-NPs were active against P. aeruginosa, K. pneumoniae and E. coli. The permeation study across rat ileum showed 2.6-fold improvement in Papp for A-NPs than A-S2 This increase in permeability is due to the uptake of nanoparticles by Peyer's patches of intestinal epithelium and endocytic uptake via enterocytes. Flow cytometric analysis demonstrated 2.2-fold higher uptake of Rh B-NPs3 than Rh B-S4 and elucidated the dominance of enterocytes mediated endocytosis of nanoparticles. Furthermore, stability data collected as per ICH guidelines for three months under accelerated conditions had shown that the A-NPs were stable. The purported drug delivery system hence, seems a promising tool to replace successfully the current intravenous therapy and is used to support relevant patient compliance thereby, adding value to the "patient care at home".

Opioid-free anesthesia for breast cancer surgery: An observational study.

BACKGROUND AND AIMS: Opioids are associated with postoperative nausea, vomiting, drowsiness, and increased analgesic requirement. A nonopioid anesthesia technique may reduce morbidity, enable day care surgery, and possibly decrease tumor recurrence. We compared opioid-free, nerve block-based anesthesia with opioid-based general anesthesia for breast cancer surgery in a prospective cohort study. MATERIAL AND METHODS: Twenty four adult American Society of Anesthesiologists grade I-III patients posted for modified radical mastectomy (MRM) with axillary dissection were induced with propofol and maintained on isoflurane (0.8-1.0 minimum alveolar concentration) through i-gel on spontaneous ventilation and administered ultrasound-guided PECS 1 and 2 blocks (0.1% lignocaine + 0.25% bupivacaine + 1 mcg/kg dexmedetomidine, 30 ml). Postoperative nausea, pain scores, nonopioid analgesic requirement over 24 h, stay in the recovery room, and satisfaction of surgeon and patient were studied. Twenty-four patients who underwent MRM and axillary dissection without a nerve block under routine opioid anesthesia with controlled ventilation were the controls. RESULTS: MRM and axillary dissection under the nonopioid technique was adequate in all patients. Time in the recovery room, postoperative nausea, analgesic requirement, and visual analog scale scores were all significantly less in the nonopioid group. Surgeon and patient were satisfied with good patient quality of life on day 7. CONCLUSION: Nonopioid nerve block technique is adequate and safe for MRM with axillary clearance. Compared to conventional technique, it offers lesser morbidity and may allow for earlier discharge. Larger studies are needed to assess the long-term impact on chronic pain and tumor recurrence by nonopioid techniques.

Circulating genotypes of Pneumocystis jirovecii and its clinical correlation in patients from a single tertiary center in India.

The present study was carried out with the objectives of genotyping Pneumocystis jirovecii at three distinct loci, to identify the single nucleotide polymorphisms (SNPs), and to study its clinical implications in patients with Pneumocystis pneumonia (PCP). Analysis of genetic diversity in P. jirovecii from immunocompromised patients was carried out by genotyping at three distinct loci encoding mitochondrial large subunit rRNA (mtLSU rRNA), cytochrome b (CYB), and superoxide dismutase (SOD) using polymerase chain reaction (PCR) assays followed by direct DNA sequencing. Of the 300 patients enrolled in the present study, 31 (10.33%) were positive for PCP by a specific mtLSU rRNA nested PCR assay, whereas only 15 P. jirovecii could be amplified at the other two loci (SOD and CYB). These positives were further subjected to sequence typing. Important genotypic combinations between four SNPs (mt85, SOD110, SOD215, and CYB838) and clinical outcomes could be observed in the present study, and mt85A, mt85T, and SOD110C/SOD215T were frequently associated with "negative follow-up". These SNPs were also noted to be relatively more prevalent amongst circulating genotypes in our study population. The present study is the first of its kind from the Indian subcontinent and demonstrated that potential SNPs of P. jirovecii may possibly be attributed to the clinical outcome of PCP episodes in terms of severity or fatality in different susceptible populations likely to develop PCP during their course of illness.

Dataset on the importation of the exotic shrimp Penaeus vannamei broodstock (Boone, 1931) to India.

Penaeus vannamei is an exotic shrimp species that has gained high culture momentum, since its introduction to India [1]. Currently, the culture of the species in the Country is being done by the shrimp farmers by importation of Specific Pathogen Free (SPF) vannamei broodstock from approved suppliers, which are located overseas. The value of one brooder normally ranges from 50 to 61 US $, excluding the custom duty, processing fee and other charges for the transboundary shipment of the stock to India. The P. vannamei stock are permitted to be imported to the Country by the hatchery operators only through the single declared port of entry, i.e. Chennai in Tamil Nadu in the Country. The imported parent shrimps are then to be quarantined at the Aquatic Quarantine Facility before being transported to the vannamei hatcheries [2]. This article reports the data available on import of vannamei broodstock to India since its importation to India in 2009. The dataset presented here contains information on transit and quarantine mortality of the brooders following the shipment of the stock by the various broodstock suppliers from the overseas.

Diminished IL-17A levels may protect filarial-infected individuals from development of rheumatoid arthritis and systemic lupus erythematosus.

Nematode infections have been observed to inversely correlate with autoimmune disorders. Recently, we have shown the absence of filarial infection in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) who live in filarial-endemic areas. The mechanism(s) by which filarial-infected individuals are protected against the development of RA or SLE are unknown. In mice CIA, an experimental model for RA, ES-62, an execratory product of rodent filarial nematode , has been shown to improve arthritis through suppression of the IL-17 pathway. A total of 160 individuals, 40 each of endemic normal, filarial-infected cases, SLE and RA patients, from filarial-endemic areas, were enrolled in the study. Plasma levels of IL17-A, IFN-α and TNF-α were quantified by enzyme-linked immunosorbent assay (ELISA). RA and SLE patients displayed significantly higher plasma IL-17A, IFN-α and TNF-α levels compared to endemic normal and infected individuals. Furthermore, IL-17A levels were significantly low in participants with filarial infection compared to endemic controls ( p < 0.05). Interestingly, plasma IL-17A levels correlated inversely with circulating filarial antigen (CFA) ( p = 0.004, Spearman r = -0.51). Filarial infection was associated with low plasma IL-17A levels, a mechanism by which it possibly protects individuals in filarial-endemic areas from the development of autoimmune disorders like RA and SLE.

Association of p53 codon72 Arg>Pro polymorphism with susceptibility to nasopharyngeal carcinoma: evidence from a case-control study and meta-analysis.

Tumor suppressor p53 is a critical player in the fight against cancer as it controls the cell cycle check point, apoptotic pathways and genomic stability. It is known to be the most frequently mutated gene in a wide variety of human cancers. Single-nucleotide polymorphism of p53 at codon72 leading to substitution of proline (Pro) in place of arginine (Arg) has been identified as a risk factor for development of many cancers, including nasopharyngeal carcinoma (NPC). However, the association of this polymorphism with NPC across the published literature has shown conflicting results. We aimed to conduct a case-control study for a possible relation of p53 codon72 Arg>Pro polymorphism with NPC risk in underdeveloped states of India, combine the result with previously available records from different databases and perform a meta-analysis to draw a more definitive conclusion. A total of 70 NPC patients and 70 healthy controls were enrolled from different hospitals of north-eastern India. The p53 codon72 Arg>Pro polymorphism was typed by polymerase chain reaction, which showed an association with NPC risk. In the meta-analysis consisting of 1842 cases and 2330 controls, it was found that individuals carrying the Pro allele and the ProPro genotype were at a significantly higher risk for NPC as compared with those with the Arg allele and the ArgArg genotype, respectively. Individuals with a ProPro genotype and a combined Pro genotype (ProPro+ArgPro) also showed a significantly higher risk for NPC over a wild homozygote ArgArg genotype. Additionally, the strength of each study was tested by power analysis and genotype distribution by Hardy-Weinberg equilibrium. The outcome of the study indicated that both allele frequency and genotype distribution of p53 codon72 Arg>Pro polymorphism were significantly associated with NPC risk. Stratified analyses based on ethnicity and source of samples supported the above result.

Effect of Supplementing Organic Forms of Zinc, Selenium and Chromium on Performance, Anti-Oxidant and Immune Responses in Broiler Chicken Reared in Tropical Summer.

Two experiments were conducted to study the effect of supplementing organic forms of zinc (Zn), selenium (Se) and chromium (Cr) on performance, anti-oxidant activities and immune responses in broiler chickens from 1 to 21 days of age, which were reared in cyclic heat-stressed condition under tropical summer in open-sided poultry house. A total of 200 (experiment I) and 450-day-old (experiment II) broiler male chicks (Cobb 400) were randomly distributed in stainless steel battery brooders (610 mm × 762 mm × 475 mm) at the rate of five birds per pen. A maize-soybean meal-based control diet (CD) containing recommended (Vencobb 400, Broiler Management Guide) concentrations of inorganic trace minerals and other nutrients was prepared. The CD was supplemented individually with organic form of selenium (Se, 0.30 mg/kg), chromium (Cr, 2 mg/kg) and zinc (Zn, 40 mg/kg) in experiment I. In experiment II, two concentrations of each Zn (20 and 40 mg/kg), Se (0.15 and 0.30 mg/kg) and Cr (1 and 2 mg/kg) were supplemented to the basal diet in 2 × 2 × 2 factorial design. A group without supplementing inorganic trace minerals was maintained as control group in both experiments. Each diet was allotted randomly to ten replicates in both experiments and fed ad libitum from 1 to 21 days of age. At 19th day of age, blood samples were collected for estimation of anti-oxidant and immune responses. Supplementation of Se, Cr and Zn increased (P < 0.05) body mass gain (BMG) and feed intake compared to those fed the CD in experiment I. The feed efficiency (FE) in Cr-fed group was higher (P < 0.05) compared to the CD-fed group. Se or Cr supplementation reduced lipid peroxidation (LP) compared to broilers fed the CD. In experiment II, BMG was not affected (P > 0.05) by the interaction between levels of Zn, Se and Cr in broiler diet. The FE improved (P < 0.05) with supplementation of the trace minerals tested at both concentrations except in group fed 40 mg Zn, 0.5 mg Se and 1 mg Cr/kg. Reduction in lipid peroxidation (LP, P < 0.05) and increased (P < 0.05) activity of superoxide dismutase were observed in broiler fed organic Zn, Se and Cr compared to the CD-fed group. The dietary concentrations of Zn, Se and Cr did not influence (P > 0.05) the immune responses (Newcastle disease titre and cell-mediated immune response to phytohaemagglutinin-P) in both the experiments. Based on the results, it is concluded that supplementation of organic form of Se, Cr and Zn (0.30, 2 and 40 mg/kg, respectively) either alone or in combination significantly improved performance and anti-oxidant responses (reduced LP and increased superoxide dismutase) in commercial broiler chicks (21 days of age) reared in cyclic heat stress conditions in open-sided poultry house during summer.

Effect of preservatives, temperature and storage duration on stability of nucleic acids of pleopod tissues of Penaeus vannamei (Boone) and screening of viral infections.

In shrimp farming, screening for economically significant viral pathogens in nucleic acids of shrimps is vital for disease surveillance programmes and further, to take necessary precautions to ensure the sustainability of the farms and thereby the shrimp industry. Different preservatives, temperature and storage durations of the pleopod tissues of Penaeus vannamei broodstock were tested to investigate its effect on the quality and quantity of the nucleic acids. The pleopods were subjected to two preservation regimes and the yield and stability of the extracted nucleic acids were monitored over a time period of 12 months. Stability of the nucleic acids was assessed with nested polymerase chain reaction, and the yield was checked spectrophotometrically. Data was analysed by performing two way ANOVA and Tukeys Paired test. Preservation treatments included storage at -20 degrees C and 5 degrees C in RNAlater and in 70% ethanol. Significant variation (P < 0.05) was observed in both DNA and RNA yield and stability from ethanol and RNAlater stored pleopods at 5 degrees C. However, the yield and stability did not differ (P > 0.05) in both the preservatives at -20 degrees C. The RNA was degraded and yielded lesser quantity when pleopod tissues were stored in ethanol at -20 degrees C than when stored in RNAlater during storage duration of 9 months. This study would help the shrimp farmers and researchers to adopt better preservation strategy, vital for shrimp disease surveillance programmes and for traceability studies in the event of any disease outbreak.

Effect of dietary inclusion of toasted guar (Cyamopsis tetragonoloba) meal as a source of protein on performance of White Leghorn layers.

Two experiments were conducted to study the effect of including toasted (120°C/35 min) guar meal (GM, Cyamopsis tetragonoloba) in the diet on performance and egg shell quality of White Leghorn (WL) layers. Totals of 2376 and 2816 layer chickens (Babcock, BV 300) were randomly distributed into 27 and 32 replicates with 88 birds each in Experiments 1 and 2, respectively. Three diets in Experiment 1 (0, 50 and 100 g GM) and 4 diets in Experiment 2 (0, 50, 100 and 150 g GM/kg) were prepared having similar concentrations of energy and protein. Each diet was fed ad libitum to 9 and 8 replicates, respectively, in Experiments 1 (from 53 to 68 weeks) and 2 (35 to 46 weeks of age). Compared to soya bean meal (SBM) GM contained similar concentrations of protein, but was deficient in all essential amino acids except arginine, which was 70% higher than in SBM. Total non-starch polysaccharide (NSP) content in GM (166 g/kg) was lower than that of SBM (179 g/kg). Amongst different NSP fractions, GM contained higher levels of arabans, xylans, mannans and glucans compared to SBM. The galactomannan gum content in GM was 46 g/kg. Egg production (EP), body weight (BW), food intake (FI), food efficiency (FE) and egg quality (shell weight, shell per cent, shell thickness, Haugh unit score, egg density and egg breaking strength) parameters were not affected by incorporating GM up to 100 g/kg diet in Experiment 1. However, egg weight (EW) and egg mass (EM) were reduced significantly in groups fed on 100 g/kg diet. In Experiment 2, EP and FE were not affected by incorporating GM up to 100 g/kg, but were reduced at 150 g/kg diet. FI, EW, BW and egg quality parameters were not affected by incorporating toasted GM up to 150 g/kg diet. Based on the results of both experiments, it is concluded that toasted GM can be included in WL layer diets up to 100 g/kg without affecting EP, FE, EW, EM, Haugh unit score, BW and egg shell quality parameters.

Development of a recombinant hCG-specific single chain immunotoxin cytotoxic to hCG expressing cancer cells.

A large number of cancers express human chorionic gonadotropin (hCG) or its subunits ectopically. Patients harboring such cancers have poor prognosis and adverse survival. PiPP is a monoclonal antibody of high affinity and specificity for hCGß/hCG. Work was carried out to develop a PiPP based recombinant immunotoxin for the immunotherapy of hCG expressing cancers. Recombinant PiPP antibody was constructed in scFv format in which gene encoding the VH and VL domains were joined through a linker. This scFv gene was fused to the gene expressing Pseudomonas exotoxin (PE38), and cloned in a Escherichia coli based expression vector under the control of strong bacteriophage T7 promoter. Immunotoxin conjugating scFv(PiPP) and PE38, was expressed in E. coli as recombinant protein. Recombinant PiPP immunotoxin was purified from the bacterial cell lysate and tested for binding and killing of hCGß expressing lymphoma, T-lymphoblastic leukemia and lung carcinoma cells in vitro. Immunotoxin showed nearly 90% killing on the cells. This is the first ever report on recombinant immunotoxin for binding and cytotoxicity to hCG expressing cancer cells, and thus can be a potential candidate for the immunotherapy of hCG expressing cells.

Children's preferences concerning ambiance of dental waiting rooms.

AIM: Despite many advances in paediatric dentistry, the greatest challenge for any paediatric dentist is to remove the anxiety related to a dental visit and have a child patient to accept dental treatment readily. Minor changes made in the waiting room design can have a major effect on the way any child perceives the upcoming dental experience. This study was carried out to determine children's preferences regarding the dental waiting area so as to improve their waiting experience and reduce their preoperative anxiety before a dental appointment. STUDY DESIGN: This was a cross-sectional descriptive study using survey methodology. METHODS: A questionnaire designed to evaluate children's preferences regarding the waiting room was distributed to new paediatric patients, aged between 6 and 11 years of age, attending an outpatient dental facility and was completed by 212 children (127 males, 85 females). STATISTICS: The analyses were carried out on cross-tables using Phi (for 2×2 tables) or Cramer's V (for larger than 2×2 tables) to assess responses to the questionnaire items across age groups and gender. RESULTS: A majority of children preferred music and the ability to play in a waiting room. They also preferred natural light and walls with pictures. They preferred looking at an aquarium or a television and sitting on beanbags and chairs and also preferred plants and oral hygiene posters Repetious. CONCLUSIONS: The results obtained from this study may help the dental team decide on an appropriate design of their paediatric waiting room so as to make children comfortable in the dental environment and improve delivery of health care.

Serum ferritin level correlates with SLEDAI scores and renal involvement in SLE.

INTRODUCTION: Ferritin is an acute-phase reactant that is elevated in various autoimmune disorders. Serum ferritin levels have been positively correlated with disease activity scores of rheumatoid arthritis and systemic lupus erythematosus (SLE). Further, enhanced levels of ferritin have also been reported in lupus nephritis. However, there are no reports from the Indian subcontinent. METHODS: Seventy-six female SLE patients, diagnosed on the basis of revised ACR criteria, and 50 healthy females, age matched from similar geographical areas, were enrolled in the present study. Serum levels of ferritin, IFN-α and IL-6 were quantified by enzyme-linked immunosorbent assay (ELISA). Clinical, biochemical, serological and other markers of disease activity (C3, C4 and anti-dsDNA) were measured by standard laboratory procedure. RESULTS: Serum ferritin levels were significantly higher in SLE patients compared to healthy controls (p < 0.0001). Ferritin levels positively correlated with SLE Disease Activity Index (SLEDAI) (p = 0.001, r = 0.35), anti-dsDNA (p = 0.001, r = 0.35), IFN-α (p < 0.0001, r = 0.51) and IL-6 (p < 0.0001, r = 0.65) and negatively correlated with C3 (p = 0.0006, r = -0.38) and C4 (p = 0.01, r = -0.28). Interestingly, serum levels of ferritin were positively associated with proteinuria (p = 0.001, r = 0.36), serum urea (p = 0.0004, r = 0.39) and serum creatinine (p = 0.0006, r = 0.38). CONCLUSION: Serum ferritin is an excellent marker of disease activity and renal dysfunction in SLE.

Enhanced virulence of the Escherichia coli O157:H7 spinach-associated outbreak strain in two animal models is associated with higher levels of Stx2 production after induction with ciprofloxacin.

Shiga toxin (Stx)-producing Escherichia coli (STEC) causes hemorrhagic colitis and the hemolytic-uremic syndrome (HUS). STEC strains may produce Stx1a and/or Stx2a or variants of either toxin. A 2006 spinach-associated outbreak of STEC O157:H7 resulted in higher hospitalization and HUS rates than previous STEC outbreaks. The spinach isolate, strain K3995, contains both stx2a and stx2c. We hypothesized that the enhanced virulence of K3995 reflects the combination of stx2 alleles (carried on lysogenic phages) and/or the amount of Stx2 made by that strain. We compared the virulence of K3995 to those of other O157:H7 isolates and an isogenic Stx2 mutant in rabbits and mice. We also measured the relative levels of Stx2 produced from those strains with or without induction of the stx-carrying phage. Some rabbits infected with K3995 exhibited intestinal pathology and succumbed to infection, while none of those infected with O157:H7 strain 2812 (Stx1a(+) Stx2a(+)) died or showed pathological signs. Rabbits infected with the isogenic Stx2a mutant K3995 stx2a::cat were not colonized as well as those infected with K3995 and exhibited no signs of disease. In the streptomycin-treated mouse model, more animals infected with K3995 died than did those infected with O157:H7 strain 86-24 (Stx2a(+)). Additionally, K3995 produced higher levels of total Stx2 and toxin phage DNA in cultures after phage induction than did 86-24. Our results demonstrate the greater virulence of K3995 compared to other O157:H7 strains in rabbits and mice. We conclude that this enhanced virulence is linked to higher levels of Stx2 expression as a consequence of increased phage induction.