Development of Low-Serum Culture Media for the in Vitro Cultivation of Theileria annulata S15 Cell Line

Background

The production of bovine theileriosis vaccine involves in vitro cultivation of Theileria annulata schizont-infected cell lines. Fetal bovine serum (FBS) is commonly used in animal cell culture, including the Theileria cell line. However, we aimed to reduce the amount of serum needed for cell culture by modifying the Stoker culture medium with supplements such as excretion factor and serum substitutes.

Methods

To evaluate the effectiveness of these modifications, techniques such as cell counting, cell viability assays, and genomic analysis were employed in the Parasitic Vaccines Production Department of Razi institute of Iran, from 2020 to 2022. Statistical analysis was used to compare the results of different experimental conditions.

Results

The three experimental media were as effective as the commonly used 10% Stoker medium in supporting the growth and viability of cells.

Conclusion

The significant reduction in the required amount of serum and the remarkable cell growth achieved by using defined serum replacements for the production of cell culture media is a significant step towards the preparation of a proper cell culture medium for the production of bovine Theileriosis vaccine.

Molecular identification of Theileria spp. in ruminants and ticks from southern littoral of Caspian Sea, Iran

The present study aimed at evaluating the presence of tick-borne apicomplexan parasites including Theileria ovis, Theileria lestoquardi, Theileria annulata, and Theileria orientalis in 92 cattle and 105 sheep from 6 different districts of Guilan and Mazandaran Provinces, in the southern littoral of Caspian Sea. Furthermore, ixodid ticks were collected from the same animals. Stained blood smears were microscopically evaluated for the presence of blood parasites, and a specific PCR was applied for the detection of Theileria species. Besides, ticks were subsequently examined by species-specific PCR. Microscopic examination of blood smears demonstrated no evidence of intraerythrocytic piroplasms. Species-specific diagnostic PCRs demonstrated that 52.17% of sheep blood samples were positive for T. ovis. In addition, 31.03% and 24.13% of cattle blood samples were positive for T. annulata and T. orientalis, respectively. Moreover, 3 species of the ixodid ticks, namely, Rhipicephalus annulatus (58.47%), Ixodes ricinus (29.82%), and Haemaphysalis inermis (11.69%), were identified in Guilan Province, while Hyalomma detritum (73.03%) and Rhipicephalus sanguineus (26.92%) were found in Mazandaran Province. Additionally, by obtaining the data with respect to tick-borne apicomplexan parasites in 122 infected ticks, 35.24%, 22.95%, and 2.45% of tick samples were positive for T. annulata, T. orientalis, and T. ovis, respectively. Species-specific PCR revealed that H. inermis and R. annulatus were positive for T. orientalis. In addition, T. annulata was found in R. annulatus, H. inermis, and H. detritum. Besides, T. ovis was the only species of Theileria found in R. sanguineus. In conclusion, the results revealed that T. annulata infection was prevalent among cattle and ovine theileriosis caused by T. ovis was the only Theileria species found in sheep in the studied areas of the southern littoral of Caspian Sea. R. annulatus, H. inermis, and H. detritum were the main vectors for T. annulata, followed by H. inermis and R. annulatus for T. orientalis, and R. sanguineus for T. ovis.

Babesia canis caused clinical babesiosis in a female Shih Tzu dog

A 2-year-old female Shih Tzu dog was submitted with the history of anorexia and depression for one week and no prior surgery. Fever and pale mucosa were noticed in physical examination. Microscopic examination of the Giemsa-stained blood smear disclosed large form of Babesia and single to four pear-shaped merozoites within erythrocytes (RBCs). Regenerative anemia characterized by a marked reticulocytosis, significant intra-vascular hemolysis, nucleated RBCs, left-shifted neutrophils, thrombocytopenia, azotemia, high serum creatinine and urea concentrations were recorded following hemato-biochemical analysis. Abundant bilirubin crystals and abnormal reddish color after centrifugation were observed in urinalysis. Molecular analysis was performed using specific primers for detection of Babesia canis. Diminazene aceturate, ciprofloxacin, ivermectin and phosphorus-vitamin B12 were prescribed and the clinical signs improved after four days. Two months follow-up showed no recurrence. Such studies would significantly contribute to the development of appropriate preventive strategies and successful treatment. This communication reports a clinical case of canine babesiosis caused by B. canis in a female Shih Tzu dog.

Molecular Identification and Genotyping of Theileria Orientalis Type 3 (Buffeli) Isolated from Cattle Using Nested-PCR Assay in Guilan Province, Iran

Protozoan parasites of the genus Theileria are tick-borne parasites that have been found in many species of mammals. More than a dozen species of Theileria have been found in cattle, water buffalo, sheep, and goats. Theileria orientalis is a non-pathogenic blood protozoan parasite that was detected and identified during a regular investigation of piroplasmida infection in indigenous cattle in the spring of 2019 in Northern Provinces of Iran. In total, 92 blood samples were collected from different areas of Guilan and Mazandaran Provinces, Iran during the spring. The Giemsa stained blood smears did not show any parasitic infection; however, T. orientalis was identified by 18S rRNA gene polymerase chain reaction (PCR) and DNA sequencing. The specific sequenced DNA for T. orientalis was registered in GenBank under the accession number MN453385. The partial 18S rRNA gene sequence of the obtained DNA showed 100% nucleotide identity with reference sequences for the T. orientalis that have been registered from Europe, Africa, and Asia. Additionally, molecular phylogenetic studies have shown that T. orientalis Iran GC98-01 isolate belongs to nonpathogenic T. orientalis type 3 (buffeli). In this study, the indigenous Bos indicus cattle were detected as asymptomatic carriers of Theileria spp. infection. Here, we identified and genotyped T. orientalis for the first time as T. orientalis type 3 (buffeli) in Iran using molecular phylogenetic analysis and registered the 18S rRNA gene sequence of the T. orientalis GC98-01 isolate in GenBank. Moreover, rare T. annulata infection was detected in cattle using semi-nested PCR in Mazandaran (Miankaleh peninsula). The T. orientalis can be differentiated from other Theileria and Babesia haemoprotozoan parasites by specific molecular assays.

Molecular Characterization and Phylogenetic Analysis of Pathogenic Theileria spp. Isolated from Cattle and Sheep based on Cytochrome b Gene in Iran

The present study investigated the phylogenetic relationship based on cytochrome b gene sequences among pathogenic Theileria species (spp.) in Iran, including Theileria annulata and Theileria lestoquardi, along with other data available in GenBank. A total of 136 (cattle) and 80 (sheep) blood samples suspected of piroplasm infection were obtained from six different provinces of Iran. Both microscopic and molecular methods using species-specific primers were used for screening T. annulata and T. lestoquardi positive samples. Finally, the partial cytochrome b gene of 30 T. annulata and 5 T .lestoquardi were amplified, sequenced, and deposited in GenBank. The results indicated that there were 12 different genotypes among T. annulata isolates, while only one genotype was observed among T. lestoquardi isolates. T. lestoquardi infection in cattle was detected in one sample, and no T. annulata and T. lestoquardi coinfection were detected in sheep and cattle. In the phylogenetic tree, different Theileria spp. were placed in separate clades, and the reliability of depicted tree and monophyly of T. annulata and T. lestoquardi ingroups were supported by the bootstrap value of 94% which significantly indicated that these two species evolved from a common ancestor. The tree also showed that these two pathogenic spp. shared a more recent common ancestor, compared to another species of Theileria parasites. To the best of our knowledge, this study is the first phylogenic analysis of pathogenic Theileria spp. in Iran based on the cytochrome b gene sequences. In addition, the first T. lestoquardi cytochrome b gene was sequenced and deposited in GenBank.

Establishment and Validation of Theileria annulata Sporozoite Ak-93 Infection in Laboratory-Reared Hyalomma anatolicum Tick Using In Vivo and In Vitro Assays

Background:

Tropical Theileriosis caused by Theileria annulata is a tick-borne disease which transmitted by the ixodid tick members of the genus Hyalomma. Studies on different aspects of disease require to access infective sporozoite of parasite which produced by tick vector. This study was carried out to establish of T. annulata life cycle to achieve T. annulata infected ticks.

Methods:

Laboratory rabbit and calf were used for rearing of Hyalomma anatolicum different instars. Unfed nymphs were fed on T. annulata infected calf. Clinical signs, Giemsa stained smears and Polymerase Chain Reaction (PCR) methods were used for detection of infection in blood and tick specimens. Susceptible calf was used for confirmation of sporozoites maturation and infectivity in bioassay test.

Results:

Hyalomma anatolicum two and three-host strategies of life cycle was lasted 90 and 116 days respectively. The PCR confirmed T. annulata infection in blood and tick samples. Maturation of T. annulata sporozoites was confirmed in bioassy test. First clinical symptom of disease was seen earlier in the case of transmission of disease through feeding of live ticks in comparison with blood injection method.

Conclusion:

Complete life cycle of T. annulata was done and confirmed by clinical signs, microscopic examination, molecular methods and bioassay test. According to published reports to date, this is the first report of establishment of H. anatolicum tick infection with T. annulata using susceptible calf under controlled conditions in Iran.

Importance of miR-UL-148D Expression Pattern in Cytomegalovirus Infected Transplant Patients

Background

MicroRNAs (miRNAs) are endogenous, 18-22 nucleotide non-coding RNA molecules. Human cytomegalovirus (HCMV) is a ubiquitous and particular herpes virus that encodes miRNAs, which increases gradually in the presence of infection. One of the important viral miRNAs is HCMV-miRUL-148D, which plays a role in establishing and maintaining viral latency.

Objective

The current study aimed to evaluate the expression levels of HCMV-miRUL-148D in active and inactive HCMV infected transplant patient groups compared to healthy individuals.

Methods

Total RNA was extracted from blood samples of 60 solid organ transplant patients and 30healthy controls. In-house SYBR Green Real-Time PCR evaluated the expression levels of studied miRNAand gene.

Results

The expression level of the UL-148D gene was significantly higher in the active HCMV infectedpatients (p=0.001) compared to other groups. While the miRUL-148D expression level significantly increased in the inactive HCMV-infected patients (p<0.001) compared to other groups.

Conclusion

Increased miRUL-148D expression level in the inactive HCMV-infected transplant patients indicates the potential role of this miRUL-148D as a biomarker of the HCMV latent stage.

Detection and Molecular Characterization of Babesia canis vogeli and Theileria annulata in Free-Ranging Dogs and Ticks from Shahriar County, Tehran Province, Iran

Background:

We aimed to detect and characterize vector-borne parasites of Babesia and Theileria in dog and ticks by PCR assay. Canine babesiosis is a significant tick-borne disease caused by different Babesia species. As the infection has not been reported in Shahriar region Tehran, Iran, molecular techniques allowed us to identify tick-borne parasites in asymptomatic dogs.

Methods:

The number of 40 dog peripheral blood samples and 27 skin attached ticks were analyzed by molecular PCR assay. The specific primers were used for detecting Babesia canis, B. gibsoni and T. annulata.

Results:

B. c. vogeli was detected in 10 dog blood samples (25%). Additionally, T. annulata infection was identified in 13 dog blood samples (32.5%) and 18 isolated tick DNAs (66.7%). The results of PCR were confirmed by 18S rRNA and Tams1 gene sequence analyzing and have been registered in GenBank under following accession numbers for B. c. vogeli (MH793502) and T. annulata (MK105284). Conclusion: The verification of T. annulata infection in free-ranging dogs and ticks shows dogs might be considered as important natural carriers/reservoirs for T. annulata in enzootic region for bovine theileriosis. The obtained data may be useful for veterinary practitioners and dog owners to aware of Babesia and Theileria infection in dog and tick to establish the effective preventive measures.

Molecular detection of Theileria spp. and Babesia ovis Infection in Sheep in Baneh, Iran

The purpose of the present study was to investigate the Theileria and Babesia infection in sheep using polymerase chain reaction (PCR) assay in Baneh, Iran. Theileria and Babesia are apicomplexan parasites that have both vertebral and invertebrate hosts. These protozoa, which are transmitted by tick vectors, are considered to be the most important causes of parasitic diseases in Iran.The detection methods of Babesia and Theileria spp. are morphological examination, serology tests, and more recently, molecular assays, such as PCR. In this study, a total of 66 blood samples were collected and analyzed using specific primers for Theileria annulata, T. ovis, T. lestoquardi, and Babesia ovis. Two PCR methods were used, namely semi-nested PCR and competitive PCR. Based on the results of the PCR assay of 66 sheep blood samples, B. ovis, T. ovis, T. lestoquardi, and T. annulata were detected in 57 (86.4%), 28 (42.4%), 0, and 16 (24%) cases, respectively. Detection of low levels of protozoan infection with high morbidity in the tested animals shows their status as a carrier that keeps the infection in the region and extends the protozoan life cycle. Another important factor is the geographical situation of Baneh as a border city since the hemoprotozoan infection is present in this region. Moreover, piroplasmida infection was found in Iraq and other neighboring provinces. Therefore, animal husbandry in Baneh is at the risk of infection with Babesia and Theileria. The collected data in this study are useful for reaching a better understanding of the epizootiology of theileriosis and babesiosis, in order to control and prevent the diseases in this region.

Association between Interleukin-21, 23 and 27 Expression and Protein Level with Cytomegalovirus Infection in Liver Transplant Recipients

BACKGROUND

Cytokines have regulatory crosstalk with CMV infection leading to manage of post-liver transplantation virus-related outcomes.

OBJECTIVE

To investigate the link between IL-21, IL-23 and IL-27 mRNA and protein level with active CMV infection, which was evaluated in reactivated and non-reactivated liver transplant recipients.

METHODS

Two groups of liver transplant recipients were enrolled in this study-54 without and 15 with active CMV infection. 3 EDTA-treated blood samples were taken on day 1, 4, and 7 post-liver transplantation. Plasma and buffy coats of all samples were separated. All samples were analyzed for CMV reactivation using antigenemia technique. The separated plasma of positive samples was used for viral DNA extraction and protein evaluation. For evaluating the mRNA expression level by real-time PCR, RNA extraction and cDNA synthesis were done for all samples. Also, the protein level of studied genes was estimated by ELISA.

RESULTS

The expression level of IL-21, IL-23A and IL-27A cytokine genes was increased in CMV reactivated liver transplant recipients in comparison with CMV non-reactivated ones; IL-27A expression pattern was significant (p=0.001) at all sampling times. IL-21 significantly increased on the 2^nd and 3^rd (p=0.028 and 0.01, respectively) sampling days in CMV reactivated compared with non-reactivated patients. The expression level of IL-23A cytokine significantly increased on the 3^rd (p=0.017) sampling day in CMV reactivated compared with non-reactivated liver transplant recipients.

CONCLUSION

Elevation in the expression level of IL-21, IL-23A and IL-27A mRNA and protein level in CMV reactivated patients emphasized on the antiviral role of these cytokines in CMV reactivated liver transplant recipients.

Patient-controlled analgesia with remifentanil vs. alternative parenteral methods for pain management in labour: a Cochrane systematic review

We aimed to assess the effectiveness of remifentanil used as intravenous patient-controlled analgesia for the pain of labour. We performed a systematic literature search in December 2015 (updated in December 2016). We included randomised, controlled and cluster-randomised trials of women in labour with planned vaginal delivery receiving patient-controlled remifentanil compared principally with other parenteral and patient-controlled opioids, epidural analgesia and continuous remifentanil infusion or placebo. The primary outcomes were patient satisfaction with pain relief and the occurrence of adverse events for mothers and newborns. We assessed risk of bias for each included study and applied the GRADE approach for the quality of evidence. We included total zero event trials, using a constant continuity correction of 0.01 and a random-effect meta-analysis. Twenty studies were included in the qualitative analysis; within these, 3713 participants were randomised and 3569 analysed. Most of our pre-specified outcomes were not studied in the included trials. However, we found evidence that women using patient-controlled remifentanil were more satisfied with pain relief than women receiving parenteral opioids (four trials, 216 patients, very low quality evidence) with a standardised mean difference ([SMD] 95%CI) of 2.11 (0.72-3.49), but were less satisfied than women receiving epidural analgesia (seven trials, 2135 patients, very low quality evidence), -0.22 (-0.40 to -0.04). Data on adverse events were sparse. However, the relative risk (95%CI) for maternal respiratory depression for patient-controlled remifentanil compared with epidural analgesia (three trials, 687 patients, low-quality evidence) was 0.91 (0.51-1.62). Compared with continuous intravenous infusion of remifentanil (two trials, 135 patients, low-quality evidence) no conclusion could be reached as all study arms showed zero events. The relative risk (95%CI) of Apgar scores less than 7 at 5 min after birth compared with epidural analgesia (five trials, 1322 participants, low-quality evidence) was 1.26 (0.62-2.57).

Antibacterial activity and sensory properties of Heracleum persicum essential oil, nisin, and Lactobacillus acidophilus against Listeria monocytogenes in cheese

AIM

The aim of this study was to evaluate the antibacterial and chemical effect of Heracleum persicum essential oil (EO), nisin, Lactobacillus acidophilus, and their combination against Listeria monocytogenes both in vitro and in Iranian white cheese model.

MATERIALS AND METHODS

Chemical compositions of H. persicum EO were analyzed by gas chromatography-mass spectrometry. After production of Iranian white cheese, minimum inhibitory concentration (MIC) and minimum bactericidal concentration of EO and nisin and agar spot test of L. acidophilus against L. monocytogenes were evaluated.

RESULTS

Hexyl butanoate (25.98%), octyl isobutyrate (17.82%), methyl butyrate (14.37%), and pentyl cyclopropane (12.77%) were the main components of the EO. MIC of the EO against L. monocytogenes was 2.5 mg/mL. Combination of nisin (5.3 IU/mL) and H. persicum EO (2500 µg/mL) showed increasing effect against L. monocytogenes (fractional inhibitory concentration = 0.9), while a higher concentration of EO and nisin showed undesirable effect on the cheese flavor. Furthermore, a combination of 1012 CFU/g L. acidophilus with H. persicum EO at the concentration of 2.5 mg/mL (T12) showed acceptable sensorial and also antibacterial results in Iranian white cheese.

CONCLUSION

Combination of H. persicum EO, L. acidophilus, and nisin can be recommended as natural preservatives and flavoring agents in cheese.

Probiotic white cheese production using coculture with Lactobacillus species isolated from traditional cheeses

Aim:

The aim of the present study was to investigate the viability of lactic acid bacteria isolated from traditional cheeses and cocultured in Iranian white cheese during ripening.

Materials and Methods:

A total of 24 samples were isolated from 8 types of traditional cheeses in West Azerbaijan, Iran. Isolated species were cocultured with starter bacteria during the production of Iranian white cheese, and their viability was investigated up to 60 days of the refrigerated storage.

Results:

Of 118 isolates of Lactobacillus, 73 isolates (62%) were confirmed as facultative heterofermentative and 45 isolates (38%) as obligate homofermentative. Of the facultative heterofermentatives, 28 isolates (24%) were Lactobacillus plantarum, 24 isolates (20%) were Lactobacillus casei, and 21 isolates (18%) were Lactobacillus agilis. Obligate homofermentatives were Lactobacillus delbrueckii (21%), Lactobacillus helveticus (14%), and Lactobacillus salivarius (3%). L. plantarum, L. casei and L. helveticus were found in high enough levels(10⁶ CFU/g).

Conclusion:

According to the obtained data, it is recommended that complex starters such as L. helveticus, L. plantarum, and L. casei can be used in industrial productions of cheese to obtain exclusive properties of traditional cheeses.

The effect of inhaled nitric oxide in acute respiratory distress syndrome in children and adults: a Cochrane Systematic Review with trial sequential analysis

Acute respiratory distress syndrome is associated with high mortality and morbidity. Inhaled nitric oxide has been used to improve oxygenation but its role remains controversial. Our primary objective in this systematic review was to examine the effects of inhaled nitric oxide administration on mortality in adults and children with acute respiratory distress syndrome. We included all randomised, controlled trials, irrespective of date of publication, blinding status, outcomes reported or language. Our primary outcome measure was all-cause mortality. We performed several subgroup and sensitivity analyses to assess the effect of inhaled nitric oxide. There was no statistically significant effect of inhaled nitric oxide on longest follow-up mortality (inhaled nitric oxide group 250/654 deaths (38.2%) vs. control group 221/589 deaths (37.5%; relative risk (95% CI) 1.04 (0.9-1.19)). We found a significant improvement in PaO₂ /F_I O₂ ratio at 24 h (mean difference (95% CI) 15.91 (8.25-23.56)), but not at 48 h or 72 h, while four trials indicated improved oxygenation in the inhaled nitric oxide group at 96 h (mean difference (95% CI) 14.51 (3.64-25.38)). There were no statistically significant differences in ventilator-free days, duration of mechanical ventilation, resolution of multi-organ failure, quality of life, length of stay in intensive care unit or hospital, cost-benefit analysis and methaemoglobin and nitrogen dioxide levels. There was an increased risk of renal impairment (risk ratio (95% CI) 1.59 (1.17-2.16)) with inhaled nitric oxide. In conclusion, there is insufficient evidence to support inhaled nitric oxide in any category of critically ill patients with acute respiratory distress syndrome despite a transient improvement in oxygenation, since mortality is not reduced and it may induce renal impairment.

Comparing efficacy and safety of fibrinogen concentrate to cryoprecipitate in bleeding patients: a systematic review

BACKGROUND

Bleeding is associated with the depletion of fibrinogen, thus increasing the risk of coagulopathy, further bleeding and transfusion requirements. Both fibrinogen concentrate and cryoprecipitate replenish low plasma fibrinogen levels. This systematic review aims to identify and evaluate evidence of efficacy and safety of fibrinogen concentrate and cryoprecipitate in bleeding patients.

METHOD

Cochrane Central Register of Controlled Trials (CENTRAL), Medline, EMBASE up to 2nd of March 2015 were among the electronic search strategies of randomized controlled trials and non-randomized studies with meta-analysis employed. Studies for inclusion required bleeding patients being treated with either fibrinogen concentrate or cryoprecipitate. Mortality was the primary endpoint. Secondary outcomes included bleeding, coagulopathy, transfusion requirements and clinical complications related to the intervention. PRISMA methodology, a data-extraction form and the Cochrane risk of bias tool were all employed.

RESULTS

Four studies were eligible for inclusion in this systematic review; one randomized controlled trial (RCT) consisting of 66 patients and three observational studies involving 218 patients in total. No mortality was reported in the published papers. There were no differences in fibrinogen-level increase, bleeding, RBC transfusions or thromboembolic complications. The RCT showed a possible increased functional improvement of haemostasis after cryoprecipitate therapy compared to fibrinogen concentrate.

CONCLUSION

The available evidence directly comparing fibrinogen concentrate to cryoprecipitate is sparse and with high risk of bias. Recommendation of one product over the other for fibrinogen substitution in the bleeding patient with acquired hypofibrinogenaemia is currently not possible. Future research should guide us towards evidence-based decisions of product superiority.

Molecular identification and successful treatment of Chlamydophila psittaci (genotype B) in a clinically affected Congo African grey parrot (Psittacus erithacus erithacus)

Avian chlamydiosis is caused by Chlamydiophila psittaci with the highest infection rate in parrots (Psittacidae) and pigeons (Columbiformes). A two-year-old Congo African grey parrot was examined since the bird had shown clinical signs of anorexia, depression, diarrhea, and mild dyspnea and based on biochemical and hemathological analysis the bird was diagnosed as having anemia, leukocytosis, heterophilia, lymphopenia and monocytosis. With regards to clinical and paraclinical findings, the case was diagnosed to be carrying Chlamydiophila spp. In addition, choanal cleft and cloaca swabs were positive for Chlamydiophila spp. in a diagnostic polymerase chain reaction (PCR) (600 bp amplicon). Polymerase chain reaction products were typed by ompA gene-based PCR, using CTU/CTL primers (1050 bp amplicon). The PCR product sequence was compared with the sequences obtained from GenBank. The phylogenetic tree has revealed 100% identity with genotype B obtained from previous studies. The bird was hospitalized and treated with doxycycline regimen for 45 days, with a weekly sampling process to trace the presence of C. psittaci DNA in faecal and choanal swabs, this process continued to the point where the specimens turned negative after two weeks. Laboratory and radiology results were within normal limits after the treatment. Genotype B is predominantly isolated from Columbidae and there have not been any reports regarding the clinically affected African gray parrot with this genotype. Subsequently, to the best of our knowledge, this is the first report of chlamydiosis by genotype B on Congo African grey parrot.

Genomic diversity of Clostridium perfringens strains isolated from food and human sources

Clostridium perfringens is a serious pathogen which causes enteric diseases in domestic animals and food poisoning in humans. Spores can survive cooking processes and play an important role in the possible onset of disease. In this study, RAPD-PCR and REP-PCR were used to examine the genetic diversity of 49 isolates of C. perfringens type A from three different sources. The results of RAPD-PCR revealed the most genetic diversity among poultry isolates, while human isolates showed the least genetic diversity. Cluster analysis obtained from RAPD-PCR and based on the genetic distances split the 49 strains into five distinct major clusters (A, B, C, D, and E). Cluster A and C were composed of isolates from poultry meat, cluster B was composed of isolates from human stool, cluster D was composed of isolates from minced meat, poultry meat and human stool and cluster E was composed of isolates from minced meat. Further characterization of these strains by using (GTG) 5 fingerprint repetitive sequence-based PCR analysis did not show further differentiation between various types of strains. In conclusion, RAPD-PCR method seems to be very promising for contamination source tracking in the field of food hygiene.

Dexmedetomidine in the pediatric population: a review

Dexmedetomidine, an alpha-2 agonist approved only for sedation in adult intensive care patients, is increasingly used off-label in- and outside Europe in the pediatric setting for various indications such as to prevent agitation, as premedication in the form of intranasal, buccal and oral solution, as adjunct for elective surgery, as sedative for magnetic resonance imaging, as intraoperative analgesia, for extracorporeal shock wave lithotripsy, and as adjuvant to ropi- and bupivacaine for nerve blocks. Dexmedetomidine is also used intravenously at different intensive care units with the purpose of sedation of children. In this paper, we assess 51 minor trials in the form of 44 randomized controlled trials and 7 prospective observational studies in an attempt to update the available evidence on dexmedetomidine use in pediatrics. Furthermore, we discuss its potential indications, benefits and adverse effects. However, it is important to state that much of the existing evidence favoring dexmedetomidine in children is either extrapolated from adult studies or based on small randomized controlled trials and observational studies with their inherent methodological shortcomings and confounding factors. Based on the best current evidence dexmedetomidine is found suitable and safe for various indications. However, in order to discover its full potential, indications, dosing and safety profile for various ages and procedures, it should urgently be examined by conducting good quality pediatric trials. Finally, we provide the readers with guidance on how to apply and dose dexmedetomidine for pediatric sedation and for other indications.

Indoor aerosols: from personal exposure to risk assessment

Motivated by growing considerations of the scale, severity, and risks associated with human exposure to indoor particulate matter, this work reviewed existing literature to: (i) identify state-of-the-art experimental techniques used for personal exposure assessment; (ii) compare exposure levels reported for domestic/school settings in different countries (excluding exposure to environmental tobacco smoke and particulate matter from biomass cooking in developing countries); (iii) assess the contribution of outdoor background vs indoor sources to personal exposure; and (iv) examine scientific understanding of the risks posed by personal exposure to indoor aerosols. Limited studies assessing integrated daily residential exposure to just one particle size fraction, ultrafine particles, show that the contribution of indoor sources ranged from 19% to 76%. This indicates a strong dependence on resident activities, source events and site specificity, and highlights the importance of indoor sources for total personal exposure. Further, it was assessed that 10-30% of the total burden of disease from particulate matter exposure was due to indoor-generated particles, signifying that indoor environments are likely to be a dominant environmental factor affecting human health. However, due to challenges associated with conducting epidemiological assessments, the role of indoor-generated particles has not been fully acknowledged, and improved exposure/risk assessment methods are still needed, together with a serious focus on exposure control.

Pulmonary and cardiovascular responses of rats to inhalation of a commercial antimicrobial spray containing titanium dioxide nanoparticles

Our laboratory has previously demonstrated that application of an antimicrobial spray product containing titanium dioxide (TiO(2)) generates an aerosol of titanium dioxide in the breathing zone of the applicator. The present report describes the design of an automated spray system and the characterization of the aerosol delivered to a whole body inhalation chamber. This system produced stable airborne levels of TiO(2) particles with a median count size diameter of 110 nm. Rats were exposed to 314 mg/m(3) min (low dose), 826 mg/m(3) min (medium dose), and 3638 mg/m(3) min (high dose) of TiO(2) under the following conditions: 2.62 mg/m(3) for 2 h, 1.72 mg/m(3) 4 h/day for 2 days, and 3.79 mg/m(3) 4 h/day for 4 days, respectively. Pulmonary (breathing rate, specific airway resistance, inflammation, and lung damage) and cardiovascular (the responsiveness of the tail artery to constrictor or dilatory agents) endpoints were monitored 24 h post-exposure. No significant pulmonary or cardiovascular changes were noted at low and middle dose levels. However, the high dose caused significant increases in breathing rate, pulmonary inflammation, and lung cell injury. Results suggest that occasional consumer use of this antimicrobial spray product should not be a hazard. However, extended exposure of workers routinely applying this product to surfaces should be avoided. During application, care should be taken to minimize exposure by working under well ventilated conditions and by employing respiratory protection as needed. It would be prudent to avoid exposure to children or those with pre-existing respiratory disease.

Stuck long-term indwelling central venous catheters in adolescents: three cases and a short topical review

We present three cases of fixated vascular injection ports. Two patients had cystic fibrosis and one had an immunological defect. All catheters were made from polyurethane and implanted in adolescent patients. Indwelling time were 6-8 years. One patient's catheter was entirely integrated in the vessel wall and impossible to remove. In the other two cases, catheters were removed with great difficulty by the interventional radiologists. These cases raise important questions concerning the maximum indwelling time and the choice of catheter material when implanting permanent central venous catheters (CVCs) in adolescents. Furthermore, it highlights the importance of not breaking a CVC in the attempt to remove it.

Characterization of indoor sources of fine and ultrafine particles: a study conducted in a full-scale chamber

Humans and their activities are known to generate considerable amounts of particulate matter indoors. Some of the activities are cooking, smoking and cleaning. In this study 13 different particle sources were for the first time examined in a 32 m3 full-scale chamber with an air change rate of 1.7 +/- 0.1/h. Two different instruments, a condensation particle counter (CPC) and an optical particle counter (OPC) were used to quantitatively determine ultrafine and fine particle emissions, respectively. The CPC measures particles from 0.02 microm to larger than 1.0 microm. The OPC was adjusted to measure particle concentrations in eight fractions between 0.3 and 1.0 microm. The sources were cigarette side-stream smoke, pure wax candles, scented candles, a vacuum cleaner, an air-freshener spray, a flat iron (with and without steam) on a cotton sheet, electric radiators, an electric stove, a gas stove, and frying meat. The cigarette burning, frying meat, air freshener spray and gas stove showed a particle size distribution that changed over time towards larger particles. In most of the experiments the maximum concentration was reached within a few minutes. Typically, the increase of the particle concentration immediately after activation of the source was more rapid than the decay of the concentration observed after deactivation of the source. The highest observed concentration of ultrafine particles was approximately 241,000 particles/cm3 and originated from the combustion of pure wax candles. The weakest generation of ultrafine particles (1.17 x 10(7) particles per second) was observed when ironing without steam on a cotton sheet, which resulted in a concentration of 550 particles/cm3 in the chamber air. The highest generation rate (1.47 x 10(10) particles per second) was observed in the radiator test.

PRACTICAL IMPLICATIONS

Humans and their activities are known to generate substantial amounts of particulate matter indoors and potentially they can have a strong influence on short-term exposure. In this study a quantitative determination of the emissions of fine and ultrafine particles from different indoor sources was performed. The aim is a better understanding of the origin and fate of indoor particles. The results may be useful for Indoor Air Quality models.

Emission of phthalates from PVC and other materials

The main objective of this study was to generate quantitative and qualitative emission data on phthalates from different materials. To achieve this the existing (Chamber for Laboratory Investigations of Materials, Pollution and Air Quality) Climpaq-based procedure for simplified measurements of emissions of plasticizer from PVC and other plasticized materials was modified. It was applied to a range of products. Some of them were suspected of contributing to the indoor concentration of plasticizers. The emissions from PVC flooring, polyolefine flooring, a refrigerator list, two electric cables, PVC skirting and floor wax were studied in separate Climpaqs. The emission from the PVC flooring in the Climpaq was compared with results from the ultra-small chamber Field and Laboratory Emission Cell (FLEC). Sampling and analysis methods were optimized to measure plasticizers. Samples were taken in exhaust air from the chambers after 6, 35, 62, 105, and 150 days from the start of the experiment. PVC flooring was tested for an additional 100 days. Polyolefine covered with wax resulted in an air concentration of 22 microg/m3 of dibutylphthalate (DBP), which is two orders of magnitude larger than any other materials, but did not emit di(2-ethylhexyl)phthalate (DEHP). The other materials resulted in max concentration of approximately 1 microg/m3 of DEHP and low emissions of DBP. The concentration of DEHP in each chamber increased slowly to a rather stable level which was reached after 150 days. DBP concentrations in the chambers with PVC skirting, PVC flooring, polyolefine and floor wax reached their quasi-static equilibrium after 60 days. The modified method did not create sufficient data for the calculation of emission rates. Adsorption of emission on chamber surfaces made it impossible to use the first part of the experiment for emission rate calculation. When the concentration had stabilized, it was found to be almost identical and independent of chamber and ventilation rate. Emission rates were reduced at high concentrations probably because the concentration in the material was near equilibrium with the concentration in the chamber air.

Comparison of three small chamber test methods for the measurement of VOC emission rates from paint

The aim of this study was to demonstrate a correlation between the measurement of emission rates of volatile organic compounds (VOCs) in three different climate chambers. In order to achieve this aim, the early state of the emission process in the three chambers was investigated and the effects of some important factors on the emission rates from paint were determined. The paper presents results of measurements in three different climate chambers. For the study, a 1-m3 chamber, a field and laboratory emission cell (FLEC), and a chamber for laboratory investigation of materials pollution and air quality (CLIMPAQ) were used. The airflow and surface area were selected so that the area-specific ventilation rates were identical in the three chambers. Temperature and relative humidity were identical during all the measurements. The paint examined was a solvent-based alkyd paint intended for indoor, which use contained between 30 and 60% of white spirit in wet condition. The paint was applied to electropolished and cleaned stainless steel plates. After application, the test material was stored for 14 days for drying in a well-ventilated conditioning room before the measurements were made. After 2 weeks storage, the most pronounced emissions were pentanal, hexanal, octanal, and decanol. The period before the emission rate stabilized differed for the three chambers studied. However, all chambers gave similar emission rates within the overall uncertainty used in these experiments.

Characterization of asphalt fume composition under simulated road paving conditions by GC/MS and microflow LC/quadrupole time-of-flight MS

A highly sensitive, selective, and reliable analytical method has been developed and validated for characterization of asphalt fume generated under simulated road paving conditions. A dynamic asphalt fume generation system was modified to provide consistent test atmospheres at simulated asphalt road paving conditions. In the process of fume generation, asphalt was initially preheated in an oven to 170 degrees C, pumped to a large kettle, which maintained the asphalt temperature between 150 and 170 degrees C, and then transferred to the generator. The fume was conducted from the generator to an exposure chamber through a heated transfer line. Characterization of the asphalt fume test atmospheres included the following: (1) determination of the consistency of the asphalt aerosol composition within the generation system; (2) quantification of total organic matter of the asphalt fume by electron impact ionization of isotope dilution gas chromatography/ mass spectrometry); and (3) identification of individual priority polycyclic aromatic hydrocarbons (PAHs) in asphalt fume by selected ion monitoring. With the developed method, asphalt fumes could be characterized into three fractions: (1) filter collection of a large molecular size fraction over a range of mass-to-charge (m/z) ratios of 173-309; (2) XAD-2 trapping of a medium molecular size fraction over a range of m/z ratios of 121-197; and (3) charcoal trapping of a small molecular size fraction that contained mainly the volatile vapor fraction over a range of m/z ratios of 57-141. Total organic matter of the asphalt fume was quantified over the 5 exposure days. Sixteen specific priority PAHs were monitored and identified. These PAHs were determined at trace levels on the filter fraction. A novel approach, which utilizes collision-induced dissociation of fragmentation pathway leading to a characteristic fragmentation pattern by coupling microflow liquid chromatography to atmospheric pressure chemical ionization of quadrupole time-of-flight mass spectrometry, was used to further clarify the trace amount of key components present in simulated road paving asphalt fumes. These results demonstrate that asphalt fume composition could be characterized and specific priority PAHs could be identified by this method. The major advantages of this method are its highly sensitivity, selectivity, and reliability for chemical hazard characterization in a complex mixture. This method is suitable for support toxicity studies using simulated occupational exposure to asphalt fumes.

Flow cytometric platform for high-throughput single nucleotide polymorphism analysis

We have developed a rapid, cost-effective, high-throughput readout for single nucleotide polymorphism (SNP) genotyping using flow cytometric analysis performed on a Luminex 100 flow cytometer. This robust technique employs a PCR-derived target DNA containing the SNP, a synthetic SNP-complementary ZipCode-bearing capture probe, a fluorescent reporter molecule, and a thermophilic DNA polymerase. An array of fluorescent microspheres, covalently coupled with complementary ZipCode sequences (cZipCodes), was hybridized to the reaction products and sequestered them for flow cytometric analysis. The single base chain extension (SBCE) reaction was used to assay 20 multiplexed SNPs for 633 patients in 96-well format. Comparison of the microsphere-based SBCE assay results to gel-based oligonucleotide ligation assay (OLA) results showed 99.3% agreement in genotype assignments. Substitution of direct-labeled R6G dideoxynucleotide with indirect-labeled phycoerythrin dideoxynucleotide enhanced signal five- to tenfold while maintaining low noise levels. A new assay based on allele-specific primer extension (ASPE) was validated on a set of 15 multiplexed SNPs for 96 patients. ASPE offers both the advantage of streamlining the SNP analysis protocol and the ability to perform multiplex SNP analysis on any mixture of allelic variants.

Evaluation of percutaneous penetration of natural rubber latex proteins

Latex allergy is recognized worldwide as a serious health risk. To date, exposure assessment and intervention strategies have focused primarily on respiratory protection; this work evaluates the potential role of dermal protein penetration in the development of latex allergy. In vitro penetration models using flow-through diffusion cells and both human surgical specimens and hairless guinea pig skin (CrL: IAF/HA) demonstrated iodinated latex proteins (ammoniated and non-ammoniated) penetrating into and through both intact and abraded skin. Although less than 1% penetration was observed with intact skin, up to 23% of latex proteins applied to abraded skin were recovered from receptor fluid within 24 h of exposure. Phosphoimaging of the concentrated effluent revealed proteins ranging in size from 3 to 26 kDa. Using a (3)H(2)O penetration assay to evaluate barrier integrity, the amount of latex protein penetration was found to positively correlate with the degree of dermabrasion. Immunohistochemistry of the skin localized latex proteins in the Langerhans cell-rich epidermis and in the dermis. Both in vitro penetration studies and immunohistochemistry supported the use of hairless guinea pig skin as a surrogate for human skin in evaluating latex protein penetration. In studies performed in vivo, 35% of hairless guinea pigs topically exposed to latex proteins (100 microg) 5 days per week for 3 months demonstrated elevations in latex-specific IgG1. The implication for these data is that the skin is not only a plausible route for latex sensitization but can be a major exposure route when the integument has been compromised.

Organic dust exposure from compost handling: response of an animal model

The objective of this investigation was to elucidate the pulmonary responses of an animal model to dust generated from leaf/wood compost which had caused a severe case of acute respiratory illness in an individual. Guinea pigs were exposed for 4 hr to 30 mg/m3 of aerosolized leaf/wood compost dust. Inhalation resulted in significant cellular activation and changes in pulmonary mechanics. Maximal elevation in breathing rate (increases 36%) was observed 12-18 hr postexposure. Similarly, maximal granulocyte infiltration (increases 1,600%) and activation of alveolar macrophages (increases 65%) occurred 18 hr postexposure. In contrast, maximal airway obstruction (increases 120%) occurred immediately after exposure and returned toward normal (increases 53%) by 18 hr postexposure. In several respects, the airway obstruction and pulmonary inflammation described in the animal model were comparable to the human response to compost dust. Therefore, this animal model may be useful in predicting the potential respiratory hazard associated with exposure to various organic dusts.

Restricted immunoglobulin variable region gene usage by normal Ly-1 (CD5+) B cells that recognize phosphatidyl choline

5-15% of lymphocytes in the peritoneums of normal adult B10.H-2aH-4bp/Wts (2a4b) mice are CD5+ (Ly-1) B cells that recognize phosphatidyl choline (PtC), a phospholipid component of all mammalian cells. We produced a set of IgM-secreting hybridomas from the peritoneal cells of normal, adult 2a4b mice. We found that this set of hybridomas shows a similarly high frequency of antibodies specific for PtC (21 of 86) that also react with bromelain-treated mouse erythrocytes. Restriction fragment analysis of Ig gene rearrangements and analysis of expressed Ig idiotypes reveal that these cells use a restricted set of variable region genes to generate the PtC-specific antibodies. The Ig genes used by the PtC-specific hybridomas appear to be the same as those found in the PtC-specific Ly-1 B cell lymphomas, CH27 and CH34.