A waterborne outbreak of epidemic diarrhea due to group A rotavirus in Malatya, Turkey

We characterized an outbreak of acute diarrheal disease caused by group A rotavirus that occurred during the Autumn of 2005 in Malatya City, Turkey. A total 9907 patients between 0 to 91 years old (mean age: 25.05?19.67) were included in the epidemic. The patients? data were prospectively collected and statistically analyzed. Microbiologic analyses were performed to determine the etiologic agent. Rapid onset diarrhea (98.36%), abdominal cramps (69%), fever (44.4%) and vomiting (69.6%) were the most common symptoms observed in patients. Rotavirus antigen was detected in 52.7% of the studied patients. RT-PCR analysis led to identification of Group A rotavirus as the causative agent of this epidemic. Simultaneous measurements of the drinking water samples yielded very low chlorine levels; as low as 0 to 0.05 mg/L. The outbreak investigation team indicated possible contamination of a large water depository from a water well, which supplies drinking water to two major districts of the city. Effective chlorination and blockage of the passage between the well and the water depository stopped the outbreak. This outbreak shows the high epidemic potency of rotavirus in large human populations, including all age groups, and underlines the importance of water safety in pipeline systems.     

Chiral mono and diamide derivatives of calix[4]arene for enantiomeric recognition of chiral amines

Novel chiral mono and diamide derivatives of calix[4]arene have been prepared from the aminolysis reaction of 5,11,17,23-tetra-tert-butyl-25,27-diethoxycarbonyl-methoxy-26,28-dihydroxycalix[4]arene 1 and 25,27-diethoxycarbonyl-methoxy-26,28-dihydroxycalix[4]arene 2 with chiral (S)-(-)-1-phenylethylamine (PEA) and (1S,2S)-(+)-2-amino-1-(4-nitrophenyl)-1,3-propanediol, respectively. Spectrophotometric titrations have been performed in CHCl(3) at 20-30 degrees C in order to obtain the binding constants (K) and the thermodynamic quantities (DeltaH and DeltaS) for the stoichiometric 1:1 inclusion complexation of various chiral amines with these new host compounds. Preliminary experiments were undertaken to confirm the complexation properties of receptors 9 and 13 with PEA by (1)H NMR in CDCl(3) at room temperature. The molecular recognition abilities and enantioselectivities for guests (R and S)-alpha-PEA and (R and S)-cyclohexylethylamine (CHEA) are discussed from a thermodynamic point of view.     

Repetitive Long-Term Hyperbaric Oxygen Treatment (HBOT) Administered after Experimental Traumatic Brain Injury in Rats Induces Significant Remyelination and a Recovery of Sensorimotor Function

Cells in the central nervous system rely almost exclusively on aerobic metabolism. Oxygen deprivation, such as injury-associated ischemia, results in detrimental apoptotic and necrotic cell loss. There is evidence that repetitive hyperbaric oxygen therapy (HBOT) improves outcomes in traumatic brain-injured patients. However, there are no experimental studies investigating the mechanism of repetitive long-term HBOT treatment-associated protective effects. We have therefore analysed the effect of long-term repetitive HBOT treatment on brain trauma-associated cerebral modulations using the lateral fluid percussion model for rats. Trauma-associated neurological impairment regressed significantly in the group of HBO-treated animals within three weeks post trauma. Evaluation of somatosensory-evoked potentials indicated a possible remyelination of neurons in the injured hemisphere following HBOT. This presumption was confirmed by a pronounced increase in myelin basic protein isoforms, PLP expression as well as an increase in myelin following three weeks of repetitive HBO treatment. Our results indicate that protective long-term HBOT effects following brain injury is mediated by a pronounced remyelination in the ipsilateral injured cortex as substantiated by the associated recovery of sensorimotor function.     

Spread of a single clone Acinetobacter baumannii strain in an intensive care unit of a teaching hospital in Turkey

Acinetobacter baumannii is an important nosocomial pathogen, especially in immunocomprimised patients and those hospitalized in intensive care units. After the first isolation of A. baumannii strains from the bronchial aspirates of two patients in the intensive care unit (ICU) of our hospital as a pure culture, screening studies were performed to define possible source(s). A. baumannii strains isolated from bronchial aspirates and blood cultures of the patients in ICU were collected as a possible part of the outbreak. A total of 23 screening samples collected from equipment (7), hands (4) and gloves (2) of the staff, and from ten different body regions of the patients in the ICU were cultured. Antimicrobial susceptibility test of the isolates was performed by the standardized disk-diffusion method. All isolates were subtyped by antibiogram, arbitrarily primed polymerase chain reaction (AP-PCR) and pulsed-field gel electrophoresis (PFGE) typing methods. A total of 26 A. baumannii strains including eight clinical and 18 screening isolates were identified. All isolates were susceptible only to meropenem, tobramycin, and imipenem. There was at least a 96% resistance rate to the other antibiotics tested. Antibiogram typing showed that 24 of the 26 isolates were epidemiologically related, two were unique. AP-PCR yielded two types, one of which had 21 isolates, the other had five. PFGE fingerprinting revealed that all isolates were clonally related, including four closely related and 22 indistinguishable strains. Based on the results of PFGE which has been accepted as a reference method it can be concluded that A. baumannii strains isolated from our intensive care unit originated from a single type of strain.     

Postoperative changes in serum cytokines profile and nitric oxide levels in patients with cystic echinococcosis

The aim of the present study was to examine serum cytokines and nitric oxide (NO) levels in patients with cystic echinococcosis (CE). 28 patients with CE were studied and all underwent surgery. Serum levels of tumour necrosis factor-alpha (TNF-alpha), interleukin IL-1beta, receptor of soluble IL-2R (sIL-2R), IL-6, IL-8, nitrate/nitrite, and C-reactive protein (CRP) were determined before and after induction of treatment. Data were compared with those obtained from 28 healthy volunteers. IL-6 was elevated in all CE patients (100%). IL-8 was increased in 11/28 (39.3%). Increased levels of IL-2R and TNF-alpha were found in a limited number of them particularly those showing cysts in the central area of the liver (5/28, 6/28). IL-1beta level was not elevated in any patient except in secondary severe CE. CRP and nitrate/nitrite levels were also increased. A positive correlation between CRP and IL-6 (r = 0.74; p < 0.001) was found confirming the link between inflammation due to CE and activation of monocytes. All patients completely recovered and the levels of the studied parameters reverted to normal levels except one patient in whom severe recurrent disease occurred two years after the first operation. These results suggest that there are different immunoregulatory events and cytokines response during CE and may be in part related to slight monocytosis and in part to Th2 activation. IL-6, NO and CRP were unambiguously involved in the host parasite interaction and therefore may be useful markers in monitoring CE management and evaluating surgical stress.     

Detection of Alloiococcus otitidis in the nasopharynx and in the outer ear canal

Alloiococcus otitidis has been recovered from the middle ear of children with otitis media with effusion, but its natural habitat is not known. To determine whether the nasopharynx and the outer ear canals are the natural habitats of A. otitidis, 145 swabs (50, nasopharynx; 95 outer ear canal) collected from 50 children were screened by polymerase chain reaction. A. otitidis DNA was detected in seven (4.8%) of the 145 specimens, of which four were nasopharynx, and three outer ear canal. These results indicate that the nasopharynx and outer ear canal may be the body sites for localization of A. otitidis.     

Genetic analysis of chromosomal regions of Lactococcus lactis acquired by recombinant lytic phages

Recombinant phages are generated when Lactococcus lactis subsp. lactis harboring plasmids encoding the abortive type (Abi) of phage resistance mechanisms is infected with small isometric phages belonging to the P335 species. These phage variants are likely to be an important source of virulent new phages that appear in dairy fermentations. They are distinguished from their progenitors by resistance to Abi defenses and by altered genome organization, including regions of L. lactis chromosomal DNA. The objective of this study was to characterize four recombinant variants that arose from infection of L. lactis NCK203 (Abi(+)) with phage phi31. HindIII restriction maps of the variants (phi31.1, phi31.2, phi31.7, and phi31.8) were generated, and these maps revealed the regions containing recombinant DNA. The recombinant region of phage phi31.1, the variant that occurred most frequently, was sequenced and revealed 7.8 kb of new DNA compared with the parent phage, phi31. This region contained numerous instances of homology with various lactococcal temperate phages, as well as homologues of the lambda recombination protein BET and Escherichia coli Holliday junction resolvase Rus, factors which may contribute to efficient recombination processes. A sequence analysis and phenotypic tests revealed a new origin of replication in the phi31.1 DNA, which replaced the phi31 origin. Three separate HindIII fragments, accounting for most of the recombinant region of phi31.1, were separately cloned into gram-positive suicide vector pTRK333 and transformed into NCK203. Chromosomal insertions of each plasmid prevented the appearance of different combinations of recombinant phages. The chromosomal insertions did not affect an inducible prophage present in NCK203. Our results demonstrated that recombinant phages can acquire DNA cassettes from different regions of the chromosome in order to overcome Abi defenses. Disruption of these regions by insertion can alter the types and diversity of new phages that appear during phage-host interactions.     

Mhc supertypes confer both qualitative and quantitative resistance to avian malaria infections in a wild bird population

Major histocompatibility complex (Mhc) genes are believed to play a key role in the genetic basis of disease control. Although numerous studies have sought links between Mhc and disease prevalence, many have ignored the ecological and epidemiological aspects of the host–parasite interaction. Consequently, interpreting associations between prevalence and Mhc has been difficult, whereas discriminating alleles for qualitative resistance, quantitative resistance and susceptibility remains challenging. Moreover, most studies to date have quantified associations between genotypes and disease status, overlooking the complex relationship between genotype and the properties of the Mhc molecule that interacts with parasites. Here, we address these problems and demonstrate avian malaria (Plasmodium) parasite species-specific associations with functional properties of Mhc molecules (Mhc supertypes) in a wild great tit (Parus major) population. We further show that correctly interpreting these associations depends crucially on understanding the spatial variation in risk of infection and the fitness effects of infection. We report that a single Mhc supertype confers qualitative resistance to Plasmodium relictum, whereas a different Mhc supertype confers quantitative resistance to Plasmodium circumflexum infections. Furthermore, we demonstrate common functional properties of Plasmodium-resistance alleles in passerine birds, suggesting this is a model system for parasite–Mhc associations in the wild.     

Growth of blue crab, Callinectes sapidus, in the Yumurtalik Cove, Turkey: a molt process approach

The blue crab (Callinectes sapidus) is native to the western Atlantic, but is an invasive species in the Mediterranean. This study examined the dynamics of growth in an invasive population of blue crab in the Yumurtal?k Cove, Turkey (North Eastern Mediterranean). Growth was quantified using a discontinuous growth model, a molt process model. Crab growth histories were observed for individual crabs held in field enclosures in summer 2010 and 2011. Carapace widths ranged from 14.13 to 80.07 mm. A mean growth per molt of 120.6% increase in carapace width was observed. Chronological inter-molt periods ranging between 3 days and 67 days were observed. The average IMP was 16 days in Yumurtal?k Cove. The mean physiological IMP was 270±163 degree-days, ranging from 72–781 degree-days.