Cultures Of Streptococci Research Articles

Beneficial microorganisms viability and sensory acceptance of a potentially synbiotic dairy-based tomato spread

Nowadays, important features for the development of new food products include their convenience, taste, and ability to promote beneficial effects to human health. This study aimed to develop a potentially synbiotic dairy-based tomato spread and to evaluate the viability of the microorganisms employed, as well as the sensory acceptability of the product throughout its storage for 28 days. Three different trials were studied, all containing the prebiotic inulin and the starter culture Streptococcus thermophilus ST-M6: T1 (control); T2 with the probiotic strains Lactobacillus acidophilus NCFM and Bifidobacterium animalis subsp. lactis Bb-12, and T3 with Bb-12 and the bacteriocinogenic and potentially probiotic strain Lactobacillus sakei subsp. sakei 2a. The product was stored at 4 °C and analysed after 1, 7, 14, 21, and 28 days of storage. For all trials, the pH decreased throughout storage, the viability of all strains was high (≥7.9 log cfu/g), and sensory evaluation with consumers showed mean scores above 7 during the storage period evaluated (up to 21 days), which demonstrates the product has potential as a functional food.

ACIP votes to recommend PCV13 for adults aged 65 years and older

At an interim meeting on August 13, 2014, just in time for the upcoming respiratory season, CDC's Advisory Committee on Immunization Practices (ACIP) voted 13 to 2 to recommend the pneumococcal conjugate vaccine PCV13 (Prevnar 13 - Pfizer) for adults aged 65 years and older. The committee had delayed discussion and a vote at its June meeting to gather more information on the use of PCV13 in this patient population (for details, see page 21 of the August issue).

Index of Suspicion in the Nursery

A 4.1-kg, 10-day-old, term Hispanic male infant presents to the emergency department (ED) with multiple episodes of paroxysmal jerky movements, irritability, and an episode of cyanosis. Parents report decreased responsiveness and oral intake 3 days before presentation. Patient was born at 40.1 weeks to a G2P1001 via cesarian delivery for arrest of dilatation. The Apgar scores were 9 and 9 at 1 and 5 minutes, respectively. Prenatal course and delivery history are unremarkable, including negative maternal serologies and group B Streptococcus (GBS) culture. While in the ED, the patient has 5 episodes of tonic-clonic seizures, with dropping oxygen saturation to 70%, and is intubated for airway protection. Vital signs reveal temperature of 101.5°F, heart rate of 170 beats per minute, respiratory rate of 42 breaths per minute, and blood pressure of 90/60 mm Hg. Physical examination reveals markedly decreased responsiveness with no other positive findings. A full sepsis evaluation is performed including cultures of blood, urine, cerebrospinal fluid (CSF), and computed tomography (CT) of the head. Lorazepam is started for seizures. Empiric broad-spectrum antimicrobial therapy including ampicillin, gentamicin, cefotaxime, and acyclovir is initiated. The infant is admitted for further diagnostic and therapeutic management. ### Diagnosis and Hospital Course Laboratory results revealed white blood cell (WBC) count …

Transplacental passage of vancomycin from mother to neonate

The objective of the study was to analyze a large number of patients receiving vancomycin chemoprophylaxis and evaluate the maternal and neonatal cord blood levels at the time of delivery. Every mother who entered labor with a positive group B streptococcal culture and a high-risk penicillin allergy with resistance to clindamycin or unknown sensitivity was consented to participate in the study. In the initial phase of the study, patients received the standard intravenous dose of 1 g every 12 hours. Based on the results, this was changed to a dosing of 15 mg/kg every 12 hours in the second phase and then further modified to 20 mg/kg every 8 hours in the third phase. Maternal and cord blood vancomycin levels were obtained at delivery and evaluated. A total of 55 patients consented to participate in the study, with 31 in phase I, 12 in phase II, and 12 in phase III. For the standard-dosing phase I group, only 32% of maternal and 9% of cord blood samples were therapeutic at delivery. For phase II, 50% of maternal and 33% of cord blood values were therapeutic; however, in phase III, 83% of mothers and neonates had therapeutic levels at the time of delivery. With standard dosing, only 9% of neonates have therapeutic vancomycin levels at delivery. By using a regimen of 20 mg/kg intravenous every 8 hours (maximum individual dose 2 g), the newborn therapeutic level increases above 80%. The pharmacological pattern shows that transplacental passage occurs with fetal levels equaling maternal levels, but transplacental transport is somewhat slow in both directions.

Pneumococcal vertebral osteomyelitis at three teaching hospitals in Japan, 2003–2011: analysis of 14 cases and a review of the literature

BackgroundPneumococcal vertebral osteomyelitis (PVO) is a rare disease whose clinical characteristics have not been clarified. This study aimed to investigate the clinical features and outcomes of patients with PVO.MethodsWe retrospectively evaluated all adult patients diagnosed with PVO at three teaching hospitals in Japan from January 2003 to December 2011. All cases were identified through a review of the medical records of patients with invasive pneumococcal disease (IPD).ResultsAmong 208 patients with IPD, we identified 14 with PVO (6.4%; 95% CI, 3.5–10%). All 14 patients (nine male, five female; median age 69 years) had acquired PVO outside the hospital and had no recent history of an invasive procedure or back injury. Five patients (36%) had diabetes mellitus, and four (29%) had heavy alcohol intake. Fever (n = 13; 93%) or back pain/neck pain (n = 12; 86%) were present in most patients. The lumbar spine was affected in nine patients (64%) but the cervical spine was the site of infection in four patients (29%). All patients except one had a positive blood culture for Streptococcus pneumoniae, and there were no distant infected sites in most patients (n = 10; 71%). Intravenous beta-lactam therapy was initiated within 1 week after the onset of symptoms in 11 patients (79%). No patients died within 30 days, but one patient died from aspiration pneumonia on day 37 after admission.ConclusionsPVO was relatively common among adult patients with IPD, and mortality was low in this study. S. pneumoniae may be the causative pathogen of vertebral osteomyelitis, especially among community-onset cases without a history of invasive procedures or back injury.

Elevated Inflammatory Markers Combined With Positive Pneumococcal Urinary Antigen Are a Good Predictor of Pneumococcal Community-acquired Pneumonia in Children

Our objective was to evaluate procalcitonin (PCT) and C-reactive protein (CRP) as predictors of a pneumococcal etiology in community-acquired pneumonia (CAP) in hospitalized children. Children requiring hospitalization for CAP were prospectively enrolled. The following indices were determined: antibodies against pneumococcal surface proteins (anti-PLY, pneumococcal histidine triad D, pneumococcal histidine triad E, LytB and pneumococcal choline-binding protein A), viral serology, nasopharyngeal cultures and polymerase chain reaction for 13 respiratory viruses, blood pneumococcal polymerase chain reaction, pneumococcal urinary antigen, PCT and CRP. Presumed pneumococcal CAP (P-CAP) was defined as a positive blood culture or polymerase chain reaction for Streptococcus pneumoniae or as a pneumococcal surface protein seroresponse (≥2-fold increase). Seventy-five patients were included from which 37 (49%) met the criteria of P-CAP. Elevated PCT and CRP values were strongly associated with P-CAP with odds ratios of 23 (95% confidence interval: 5-117) for PCT and 19 (95% confidence interval: 5-75) for CRP in multivariate analysis. The sensitivity was 94.4% for PCT (cutoff: 1.5 ng/mL) and 91.9% for CRP (cutoff: 100 mg/L). A value≤0.5 ng/mL of PCT ruled out P-CAP in >90% of cases (negative likelihood ratio: 0.08). Conversely, a PCT value≥1.5 ng/mL associated with a positive pneumococcal urinary antigen had a diagnostic probability for P-CAP of almost 80% (positive likelihood ratio: 4.59). PCT and CRP are reliable predictors of P-CAP. Low cutoff values of PCT allow identification of children at low risk of P-CAP. The association of elevated PCT or CRP with a positive pneumococcal urinary antigen is a strong predictor of P-CAP.

Epidemiology of OM Pathogens of Those Undergoing Tympanostomy Tube Placement in the Era of PCV13

Objectives: Determine the microbiology of otitis media (OM) since the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) in March 2010. Methods: The population included pediatric patients undergoing tympanostomy tube placement between August 2012 and June 2013. Middle ear effusion was sent for aerobic culture and antibiotic susceptibility testing. Statistical analysis will be performed to compare those who received PCV13 and those who only received the PCV7 vaccine. Preliminary data from August 2012 to December 2012 included 72 ears, of which 21 had fluid. Seven of these 21 ears cultured Staphylococcus aureus, Haemophilus influenza, and Pseudomonas aeruginosa. Three patients with positive cultures of Staphylococcus or Haemophilus were vaccinated with at least one dose of PCV13, and 2 patients that cultured Staphylococcus or Pseudomonas had the PCV7 vaccine. All of the cultures were susceptible to a quinolone. Results: Two cultures of Staphylococcus and Haemophilus were resistant to Bactrim. The impact of PCV13 on the molecular epidemiology of OM will be profound, as two of the most common pneumococcal isolates from nasopharyngeal secretions in the post-PCV7 era, serotypes 19A and 6A, are included in PCV13. This study is the first to assess the OM microbiology in a pediatric population vaccinated with PCV13. Our study is currently limited by sample size; however, this has increased, as colonization is higher in fall and winter. Conclusions: This initial lack of Streptococcus cultures indicates that PCV13 is likely to have a significant impact on antibiotic resistance and rate of pneumococcal disease during the initial years following licensure.

Accuracy of prenatal culture in predicting intrapartum group B streptococcus colonization status

Objective: To evaluate the positive predictive value (PPV) of group B Streptococcus (GBS) cultures at 35–37 weeks of gestation relative to GBS colonization status at delivery.Methods: Rectovaginal swabs from 221 women at labor in four Lisbon hospitals were collected for GBS screening according to the CDC guidelines.Results: The PPV was 24.4%. IAP was administered to 100% of prenatally GBS positive women. There was no case of early onset GBS disease (EOD).Conclusions: Poor accuracy of prenatal cultures in identifying true candidates for IAP highlights the need for Portuguese clinical and laboratory guidelines to prevent EOD and antibiotic overtreatment of pregnant women.

Correlation among Streptococcus bovis, endocarditis and septicemia in a patient with advanced colon cancer: a case report

IntroductionOne of the bacterial agents that has been found to be associated with colorectal cancer is Streptococcus bovis, with 13% of infective endocarditis cases caused by this pathogenic species.Case presentationWe describe the case of a 57-year-old Caucasian man with infiltrating and ulcerating metastatic adenocarcinoma of the sigmoid colon. The patient was receiving second-line chemotherapy treatment and, on the eighth day of the second cycle, he developed a grade IV pancytopenia. We diagnosed a severe sepsis with positive blood cultures for Streptococcus bovis/gallolyticus with a secondary endocarditis.ConclusionsA recent study suggests that the majority of patients affected by colonic cancer have a Streptococcus bovis/gallolyticus colonization that becomes apparent as an overt infection only when immunosystem disorders or cardiac valve lesions occur. This correlation is important for involving more specialists in a correct and early diagnosis of this rare, but potentially fatal, complication.

The incidence and aetiology of hospitalised community-acquired pneumonia among Vietnamese adults: a prospective surveillance in Central Vietnam

BackgroundLower respiratory tract infection (LRTI) including Community-acquired pneumonia (CAP) is a common infectious disease that is associated with significant morbidity and mortality. The patterns of aetiological pathogens differ by region and country. Special attention must be paid to CAP in Southeast Asia (SEA), a region facing rapid demographic transition. Estimates burden and aetiological patterns of CAP are essential for the clinical and public health management. The purposes of the study are to determine the incidence, aetiological pathogens, clinical pictures and risk factors of community-acquired pneumonia (CAP) in the Vietnamese adult population.MethodsA prospective surveillance for hospitalised adult CAP was conducted in Khanh Hoa Province, Central Vietnam. All adults aged ≥15 years with lower respiratory tract infections (LRTI) admitted to a provincial hospital from September 2009 to August 2010 were enrolled in the study. Patients were classified into CAP and non-pneumonic LRTI (NPLRTI) according to the radiological findings. Bacterial pathogens were identified from sputum samples by the conventional culture and polymerase chain reaction (PCR) for Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis; 13 respiratory viruses were identified from nasopharyngeal specimens by PCR.ResultsOf all 367 LRTI episodes examined, 174 (47%) were CAP. Older age, the presence of underlying respiratory conditions, and higher index score of smoking were associated with CAP. The one-year estimated incidence of hospitalised adult CAP in our study population was 0.81 per 1,000 person years. The incidence increased considerably with age and was highest among the elderly. The case fatality proportion of hospitalised CAP patients was 9.8%. Among 286 sputum samples tested for bacterial PCR, 79 (28%) were positive for H. influenzae, and 65 (23%) were positive for S. pneumoniae. Among 357 samples tested for viral PCR, 73 (21%) were positive for respiratory viruses; influenza A (n = 32, 9%) was the most common.ConclusionsThe current adult CAP incidence in Vietnam was relatively low; this result was mainly attributed to the young age of our study population.

Probiotic yogurt offers higher immune-protection than probiotic whey beverage

The probiotics can be useful to improve the immune response in experimental challenges, like the exhausting exercise, that cause immunosuppression. We have evaluated a probiotic yogurt and a probiotic whey beverage using an exhausting physical-exercise protocol with rats. Wistar rats were given a daily 4-mL supplement of each type of conventional or probiotic yogurt and whey beverage, manufactured with lactic culture Streptococcus thermophilus TA040 and Lactobacillus bulgaricus LB340, and probiotic culture Lactobacillus acidophilus LA 14 and Bifidobacterium longum BL 05. The effects on the immune system were compared to those of pair-treated cohorts receiving for 14days. Results demonstrated that the probiotic yogurt outperformed the probiotic whey beverage in blood-cell indicators (neutrophils and lymphocytes), cytokines (TNF-α and IL-1β) and various standard health parameters. In conclusion, in this study, the treadmill exercise assay successfully produced immunosuppression in the rat and the combination of the nutrients and probiotic bacteria of the yogurt reduces more effectively the adverse effects developed over the prolonged strenuous exercise than did a similar probiotic whey beverage.

Impotance of Non-Group A β-Hemolytic Streptococci in Childhood Tonsillopharyngitis

A bacterial possible agent was isolated in 38.0 % of the cases (n:1017). All cases divided into 3 groups based on the throat culture results. The patients with positive group A beta hemolytic streptococcus cultures constituted Group 1 (the mean age 6.59 years; n:729; 27.2 %). The children with non Group A beta hemolytic streptococcus formed Group 2 (the mean age 5.04 years; n:288; 10.8 %). The patients with no positive cultures and probably with a viral agent was defined as Group 3 (the mean age 5.6 years; n:1662; 62 %). The Centor score was ≥3 in 47 % of Group 1; 34 % of Group 2 and 19% of Group 3 (<0.01). Rapid streptococcus antigen test was positive in 64 % of Group 1 and there was no positive result in Group 2. Conclusion: In pediatric population, the rate of the tonsillopharyngitis with positive culture of non- Group A beta hemolytic streptococcus was 10.8 %, and 34 % of these patients had 3 or more Centor score.

Pneumococcemia in children – a retrospective study before universal pneumococcal vaccinations

To evaluate the incidence and characteristics of blood culture-positive occult pneumococcemia compared with blood culture-positive pneumococcal pneumonia in children. In years 2001-2010, 105 children with positive blood cultures for Streptococcus pneumoniae were identified from hospital electronic files. The patient cards were retrospectively charted for clinical and laboratory data, and 38 patients had and 67 had not pneumonia. The annual incidence of pneumococcemia was, on average, 29.0/10 000 at 0-12 months, 5.3/10 000 at 13-24 months and 1.9/10 000 at 2-4 years of ages, with no increasing or decreasing trend. The incidence of bacteraemic pneumococcal pneumonia increased (p = 0.022) during the study period. The duration of fever before hospitalization (<24 h 73.9% vs. 25.0%, p = 0.022) and the duration of intravenous antibiotics, usually G-penicillin (median 72 vs. 96 h, p = 0.021) was shorter in pneumococcemia patients. On admission, blood leucocyte count was higher in pneumococcemia (mean 26.6 vs. 21.9 × 10E9/L, p = 0.012), but serum CRP was higher in pneumonia (median 160 vs. 67.4 mg/L, p < 0.001). The serotypes 6B and 14 caused 53.2% of pneumococcemia cases. The incidence of pneumococcemia was highest in 1-2-year-old children, and typical for pneumococcemia was rapid onset of fever, high blood leucocyte count and a modestly elevated CRP on admission.

Accuracy of real-time PCR, Gram stain and culture for Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae meningitis diagnosis

BackgroundAlthough cerebrospinal fluid (CSF) culture is the diagnostic reference standard for bacterial meningitis, its sensitivity is limited, particularly when antibiotics were previously administered. CSF Gram staining and real-time PCR are theoretically less affected by antibiotics; however, it is difficult to evaluate these tests with an imperfect reference standard.Methods and findingsCSF from patients with suspected meningitis from Salvador, Brazil were tested with culture, Gram stain, and real-time PCR using S. pneumoniae, N. meningitidis, and H. influenzae specific primers and probes. An antibiotic detection disk bioassay was used to test for the presence of antibiotic activity in CSF. The diagnostic accuracy of tests were evaluated using multiple methods, including direct evaluation of Gram stain and real-time PCR against CSF culture, evaluation of real-time PCR against a composite reference standard, and latent class analysis modeling to evaluate all three tests simultaneously.ResultsAmong 451 CSF specimens, 80 (17.7%) had culture isolation of one of the three pathogens (40 S. pneumoniae, 36 N. meningitidis, and 4 H. influenzae), and 113 (25.1%) were real-time PCR positive (51 S. pneumoniae, 57 N. meningitidis, and 5 H. influenzae). Compared to culture, real-time PCR sensitivity and specificity were 95.0% and 90.0%, respectively. In a latent class analysis model, the sensitivity and specificity estimates were: culture, 81.3% and 99.7%; Gram stain, 98.2% and 98.7%; and real-time PCR, 95.7% and 94.3%, respectively. Gram stain and real-time PCR sensitivity did not change significantly when there was antibiotic activity in the CSF.ConclusionReal-time PCR and Gram stain were highly accurate in diagnosing meningitis caused by S. pneumoniae, N. meningitidis, and H. influenzae, though there were few cases of H. influenzae. Furthermore, real-time PCR and Gram staining were less affected by antibiotic presence and might be useful when antibiotics were previously administered. Gram staining, which is inexpensive and commonly available, should be encouraged in all clinical settings.

Pitfalls in screening streptococci for retrieving superior streptokinase (SK) genes: no activity correlation for streptococcal culture supernatant and recombinant SK

Streptokinase (SK), the heterogeneous protein family secreted by some groups of β-hemolytic streptococci (βHS), is a plasminogen activator and well-known drug for thrombolytic therapy. Differences in plasminogen activation property of streptococcal culture supernatants (SCS) have been traditionally used to identify superior producer strains and SK genes (skc) for recombinant SK (rSK) production. However, the role of SK heterogeneity and whether SK activities in SCS correlate with that of their corresponding rSK is a matter of debate. To address these concerns, SCS of nine group C streptococci (GCS) screened among 252 βHS clinical isolates were compared for plasminogen activation using S-2251 chromogenic assay. The GCS (Streptococcus equisimilis) showing the highest (GCS-S87) and lowest (GCS-S131) activities were selected for PCR-based isolation of skc, cloning and rSK production in Escherichia coli. The 6×His-tagged rSK proteins were purified by NI-NTA chromatography, analyzed by SDS-PAGE and Western blotting and their activities were determined. While SCS of GCS-S87 and GCS-S131 showed different plasminogen activations (95 and 35 %, respectively) compared to that of the reference strain (GCS-9542), but interestingly rSK of all three strains showed close specific activities (1.33, 1.70, and 1.55 × 10(4) IU mg(-1)). Accordingly, SKS87 and SKS131 had more than 90 % sequence identity at the amino acids level compared to SK9542. Therefore, SK heterogeneity by itself may not contribute to the differences in plasminogen activation properties of SCS and evaluation of this activity in SCS might not be a proper assay for screening superior skc.

Effect of Yoghurt Cultures and Probiotic Cultures on Physicochemical and Sensory Properties of Mango Soy Fortified Probiotic Yoghurt (Msfpy)

Mango soy fortified probiotic yoghurt (MSFPY) was prepared by using blends of 78.3% toned milk, 14.5% soy milk and 7.2% mango pulp. Effect of yoghurt cultures Streptococcus thermophilus (ST), Lactobacillus bulgaricus (LB) and probiotic culture Bifidobacterium bifidus (BB), Lactobacillus acidophilus (LA) on physicochemical properties and sensory properties were studied using different inoculum levels as per Response Surface Methodology (RSM). The optimized concentration of cultures was found out to be 1.75%, 1.95%, 2.44% and 1.37% for ST, LB, BB and LA respectively which yielded an acceptable quality of MSFPY having acidity 0.73%, total solids 14.02%, syneresis 14.12% and scored 8.5 on hedonic rating.

Selection and characterization of probiotic culture of Streptococcus thermophilus from dahi

For the isolation of probiotic cultures of Streptococcus thermophilus from dahi, we collected 120 samples from the southern regions of Punjab, Pakistan. Eleven isolates were obtained, and six were scrutinized for antibacterial activities against food-borne pathogens. The carbohydrate fermentation profile of these six strains was determined by the API50 CHL system. Additionally, these strains were amplified for their 16S rRNA regions to confirm their genotypic relationship. Furthermore, phenotypic characteristics among these strains were established by S-layer protein analysis of their cell walls by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and by plasmid profiling. The outer cell wall layers of these strains have 6–14 different sizes of protein bands of 27, 34, 37, 40, 45 and 60 kDa molecular weight. Similarly, except S02FT, all strains have a single prominent plasmid of 23 kbp, whereas S02FT has an additional plasmid of 9 kbp. On the basis of this unique feature and a wide spectrum of killing patterns against pathogenic bacteria, S. thermophilus S02FT was further characterized. This culture showed an optimum antibacterial activity of 800 AU/ml at pH 5.0–5.5 and a temperature of 30–37°C. It grows well in in vitro acidic conditions and tolerates bile salt up to 2% concentration. It was resistant to nalidixic acid, ciprofloxacin, gentamicin and sulphamethoxazol, but showed intermediate behaviour to vancomycin and erythromycin.

Pneumococcal Bacteremia Among Patients with Hematological Malignancies: Clinical Impact, Serotype Distribution and Antibiotic Resistance Profile in Tertiary-Care Centers

AbstractAbstract 2067 Background:Pneumococcal invasive infections are over 13 times more common among patients with hematological malignancies than in the general population. Hematopoietic stem cell transplant (HSCT) recipients, particularly those with chronic graft-versus-host disease (cGvHD), are especially vulnerable.Two types of vaccines are available for prevention: pneumococcal polysaccharide vaccine (PPSV) and pneumococcal conjugate vaccine (PCV). PPSV covers more serotypes, but concerns have been raised over immune response, particularly in immunocompromised patients.The primary goals of this study were to evaluate clinical impact of pneumococcal bacteremia, serotypes involved and resistance profile in our hematological population. Methods:We performed a retrospective study based at Hôpital Maisonneuve-Rosemont and Hôpital Notre-Dame du CHUM, both in Montreal, Canada. Among all positive blood cultures for Streptococcus pneumoniae between January 1st, 2003 and December 31st, 2011, we selected patients with hematological malignancies. We reviewed patients’ charts and electronic files. Serotypes and antibiotic susceptibility testing were done by the Laboratoire de Santé Publique du Québec. The study was approved by the hospitals’ ethics committee. Results:During the eight-year period, 54 episodes of pneumococcal bacteremia (in 52 patients) occurred among patients with hematological malignancies. Median age was 63.5 years (range 21 to 91); 44% were female. One patient was splenectomized.The main hematological malignancies were multiple myeloma (42%) and non-Hodgkin lymphoma (29%). There were 16 HSCT recipients: 10 allogeneic (8 with cGVHD) and 6 autologous. Twenty-nine patients (55%) were on chemotherapy, including 10 HSCT recipients. Among the patients with cGVHD, 3 were on trimethoprim-sulfamethoxazole (TMP-SMX) prophylaxis and 1 on pentamidine.At the time of the bacteremia, 81% of patients had a diagnosis of pneumonia (mean Fine score 118. Eleven patients were treated in the emergency department or in the outpatient clinic. Among the 43 hospitalized patients (80%), median hospitalization duration was 10 days. Intensive care unit admission was required for 9 episodes (17%). Eight patients died less than 30 days after the diagnosis of bacteremia, leading to a mortality rate of 15% and 19% among HSCT recipients.Vaccine history was not available in most patients' charts. However, all HSCT recipients should have received PPSV, as recommended in our institution. Twenty-four different serotypes were found. Theoretical coverage of these serotypes by the available vaccines was 26% for PCV-7, 35% for PCV-10, 50% for PCV-13, and 61% by PPSV; 33% episodes were not covered by any vaccine. Among patients with HSCT, the percentage of episodes not covered by any vaccine increased to 44%. PPSV covered 56% of episodes.Resistance to TMP-SMX was found in 17% of isolates. However, since 2006, all were susceptible. A third of isolates were resistant to erythromycin; the proportion of resistant isolates was higher among HSCT patients (50%). Only one isolate was resistant to fluoroquinolones, but was sensitive to all other antibiotics tested. One strain was of intermediate sensitivity to ceftriaxone, and was resistant to erythromycin and TMP-SMX. This patient was on TMP-SMX prophylaxis, and did not require admission. All strains were sensitive to penicillin and vancomycin. Conclusion:Pneumococcal bacteremia carries significant morbidity and mortality in patients with hematologic malignancies. Our mortality rate is similar to that found in other studies. Vaccination remains the cornerstone of prevention, but is imperfect in terms of immune response and coverage. One third of episodes were not covered by any available vaccine, and this proportion increased among HSCT recipients. Antibacterial prophylaxis in patients with cGVHD is therefore important and penicillin remains a good choice.In terms of treatment options for respiratory infection, given the high erythromycin resistance rate (34% vs. 20–25% found in the general population), macrolides should not be used as single agents. Third generation cephalosporins and fluoroquinolone resistance is very low, making it an interesting choices for respiratory infections. [Display omitted] Disclosures:Labbé:Pfizer: Research Funding.

The HtrA Protease from Streptococcus pneumoniae Digests Both Denatured Proteins and the Competence-stimulating Peptide

The HtrA protease of Streptococcus pneumoniae functions both in a general stress response role and as an error sensor that specifically represses genetic competence when the overall level of biosynthetic errors in cellular proteins is low. However, the mechanism through which HtrA inhibits development of competence has been unknown. We found that HtrA digested the pneumococcal competence-stimulating peptide (CSP) and constituted the primary extracytoplasmic CSP-degrading activity in cultures of S. pneumoniae. Mass spectrometry demonstrated that cleavage predominantly followed residue Phe-8 of the CSP-1 isoform of the peptide within its central hydrophobic patch, and in competition assays, both CSP-1 and CSP-2 interacted with HtrA with similar efficiencies. More generally, analysis of β-casein digestion and of digestion within HtrA itself revealed a preference for substrates with non-polar residues at the P1 site. Consistent with a specificity for exposed hydrophobic residues, competition from native BSA only weakly inhibited digestion of CSP, but denaturation converted BSA into a strong competitive inhibitor of such proteolysis. Together these findings support a model in which digestion of CSP by HtrA is reduced in the presence of other unfolded proteins that serve as alternative targets for degradation. Such competition may provide a mechanism by which HtrA functions in a quality control capacity to monitor the frequency of biosynthetic errors that result in protein misfolding.

Cream cheese as a symbiotic food carrier using Bifidobacterium animalis Bb‐12 and Lactobacillus acidophilus La‐5 and inulin

The stability of cream cheeses as a symbiotic food carrier, through supplementation with different concentrations of probiotic bacteria Bifidobacterium animalis Bb‐12 and Lactobacillus acidophilus La‐5 and the prebiotic ingredient inulin was investigated. Physicochemical parameters, pH values, total solids, fat and protein levels and the viable counts of the starter lactic culture Streptococcus thermophilus and probiotic cultures, were carried out at 1, 15, 30 and 45 days of refrigerated storage (8 ± 0.5 °C). Different physicochemical characteristics were observed in all formulations. S. thermophilus showed good viability in all the trials (6.66–9.38 log cfu/g), whereas B. animalis remained above 6 log cfu/g in all the trials during the period evaluated. However, L. acidophilus showed an accentuated decline, registering values of 3.1 log cfu/g at the end of the period studied. The results suggested that cream cheese was an adequate food matrix for supplementation with probiotic bacteria, in particular B. animalis, and the prebiotic ingredient, showing potential as a symbiotic food.