Quantitative trait loci (QTL) associated with resistance of rainbow trout Oncorhynchus mykiss against the parasitic ciliate Ichthyophthirius multifiliis.

The parasitic ciliate Ichthyophthirius multifiliis has a low host specificity eliciting white spot disease (WSD) in a wide range of freshwater fishes worldwide. The parasite multiplies rapidly whereby the infection may reach problematic levels in a host population within a few days. The parasite targets both wild and cultured fish but the huge economic impact of the protozoan is associated with mortality, morbidity and treatment in aquacultural enterprises. We have investigated the potential for genetic selection of WSD-resistant strains of rainbow trout. Applying the DNA typing system Affymetrix® and characterizing the genome of the individual fish by use of 57,501 single nucleotide polymorphisms (SNP) and their location on the rainbow trout chromosomes, we have genetically characterized rainbow trout with different levels of natural resistance towards WSD. Quantitative trait loci (QTL) used for the selection of breeders with specific markers for resistance are reported. We found a significant association between resistance towards I. multifiliis infection and SNP markers located on the two specific rainbow trout chromosomes Omy 16 and Omy 17. Comparing the expression of immune-related genes in fish-with and without clinical signs-we recorded no significant difference. However, trout surviving the infection showed high expression levels of genes encoding IgT, T-cell receptor TCRß, C3, cathelicidins 1 and 2 and SAA, suggesting these genes to be associated with protection.

Secondary immune response of rainbow trout following repeated immersion vaccination.

Teleosts are able to raise a protective immune response, comprising both innate and adaptive elements, against various pathogens. This is the basis for a widespread use of vaccines, administered as injection or immersion, in the aquaculture industry. It has been described that repeated injection vaccination of fish raises a secondary immune response, consisting of rapid, accelerated and increased antibody reaction. This study reports how rainbow trout responds to repeated immersion vaccination against yersiniosis (ERM) caused by the bacterial pathogen Yersinia ruckeri. It was found that rainbow trout does not raise a classical secondary response following repeated immersion vaccination. Serum antibody titres were merely slightly increased even after three immunizations, using 30-s immersion into a bacterin consisting of formalin-inactivated Y. ruckeri (serotype O1, biotypes 1 and 2), performed over a 3-month period. The densities of IgM-positive lymphocytes in spleen of fish immunized three times were increased compared to control fish, but no general trend for an increase with the number of immunizations was noted. The lack of a classical secondary response following repeated immersion vaccination may partly be explained by limited uptake of antigen by immersion compared to injection.

Epidermal response of rainbow trout to Ichthyobodo necator: immunohistochemical and gene expression studies indicate a Th1-/Th2-like switch.

Infections with the parasitic flagellate Ichthyobodo necator (Henneguy, 1883) cause severe skin and gill disease in rainbow trout Oncorhynchus mykiss (Walbaum, 1792) juveniles. The epidermal disturbances including hyperplasia and mucous cell exhaustion caused by parasitization are known, but no details on specific cellular and humoral reactions have been presented. By applying gene expression methods and immunohistochemical techniques, further details of immune processes in the affected skin can be presented. A population of I. necator was established in the laboratory and used to induce an experimental infection of juvenile rainbow trout. The course of infection was followed by sampling for parasite enumeration, immunohistochemistry (IHC) and quantitative PCR (qPCR) on days 0, 5, 9 and 14 post-infection. IHC showed a significant increase in the occurrence of IgM-positive cells in the skin of the infected fish, whereas IgT-positive cells were eliminated and the number of CD8-positive cells declined. qPCR studies supported the IHC findings showing a significant increase in IgM and a decrease in the CD8 gene expression. In addition, genes encoding innate immune genes such as lysozyme, SAA and cathelicidin 2 were up-regulated. Expression of cytokines (IL-1ß, IL-4/13A, IL-6, IL-8, IL-10), the cell marker CD4 and the transcription factor GATA3 showed a significant increase after infection. Cytokine profiling including up-regulation of IL-4/13A and IL-10 genes and transcription factor GATA3 connected to the proliferation of IgM producing lymphocytes suggests a partial shift towards a Th2 response associated with the I. necator infection.

Drain or No Drain Following Pancreaticoduodenectomy: The Unsolved Dilemma.

BACKGROUND AND AIMS: There is no consensus regarding the routine placement of intra-abdominal drains after pancreaticoduodenectomy. We aim to determine the effects of intraperitoneal drain placement during pancreaticoduodenectomy on 30-day postoperative morbidity and mortality. METHODS: Patients who underwent pancreaticoduodenectomy for pancreatic tumors were identified from the 2014-2015 American College of Surgeons-National Surgical Quality Improvement Program Database. Univariate and multivariate analyses adjusting for known prognostic variables were performed. A subgroup analysis was performed based on the risk for development of postoperative pancreatic leak determined by the pancreatic duct caliber, parenchymal texture, and body mass index. RESULTS: A total of 6858 patients with pancreatic tumors who underwent pancreaticoduodenectomy were identified in the 2014-2015 American College of Surgeons-National Surgical Quality Improvement Program Database dataset. In all, 87.4% of patients had intraperitoneal drains placed. A 30-day mortality rate was higher in the no-drain group (2.9% vs. 1.7%, P = 0.003). Patients in the drain group had a higher incidence of overall morbidity (49.5% vs. 41.2%, P = 0.0008), delayed gastric emptying (18.1% vs. 13.7%, P = 0.004), pancreatic fistulae (19.4% vs. 9.9%, P ⩽ 0.0001), and prolonged length of hospital stay over 10 days (43.7% vs. 34.9%, P < 0.0001). Subgroup analysis based on risk categories revealed a higher 30-day mortality rate in the no-drain group among patients with high-risk features (3.1% vs. 1.6%, P = 0.02). Delayed gastric emptying and pancreatic fistula development remained significantly higher in the drain group only in the high-risk category. Prolonged length of hospital stay and composite morbidity remained higher in the drain group regardless of the risk category. CONCLUSION: To our knowledge, this is the largest study to date that aims at clarifying the pros and cons of the intraperitoneal drain placement during pancreaticoduodenectomy for pancreatic tumors. We showed a higher 30-day mortality rate if drain insertion was omitted during pancreaticoduodenectomy in patients with softer pancreatic textures, smaller pancreatic duct caliber, and body mass index over 25. Postoperative 30-day morbidity rate was higher if a drain was inserted regardless of the risk category. Further randomized controlled trials with prospective evaluation of stratification factors for fistula risk are needed to establish a clear recommendation.

Remote ischemic conditioning in a rat model of testicular torsion: does it offer testicular protection?

BACKGROUND: Testicular torsion is a surgical emergency mainly affecting adolescent boys, with a relatively high rate of missed torsion and testicular loss secondary to delay in prompt diagnosis and surgical intervention. With ischemic reperfusion injury as its underlying culprit, testicular torsion may respond favorably to remote ischemic conditioning (RIC) where a non-privileged site (e.g. limb) is concurrently rendered ischemic to divert the cascade of reperfusion injury from the privileged organ (e.g. testicle), thus offering a protective effect in improving salvage. This mechanism is established for other organs, whereas it has not been evaluated for testis. AIM: It was aimed to evaluate RIC in a rat model of testicular torsion as a proof of principle that, similar to what has been demonstrated in other organs, RIC does offer testicular protection. STUDY DESIGN: This is an animal experimental study. Thirty Sprague-Dawley male rats were divided into control group (n = 15) and experimental group (n = 15). Non-survival surgeries of right-sided spermatic cord torsion (720° counter-clockwise twist) were performed for both the groups (45 min) followed by detorsion and reperfusion (5 min) and then orchiectomy. For the experiment group, an intervention of tail clamping to create RIC was applied 5 min after torsion, then unclamping 5 min before detorsion, followed by detorsion and reperfusion for 5 min and then orchiectomy. The testicles were histologically and immunologically examined using a hypoxia inducible factor (HIF-1α) ELISA Kit. The histological findings on ischemic changes, vascular congestion, and immunohistochemistry were quantified using previously described, validated grading systems. RESULTS: DISCUSSION: This is the first study to demonstrate the concept of RIC in an animal model of testicular torsion. It is limited by the non-availability of similar studies to compare outcomes and by the caution of extrapolating animal studies on humans. It does lay grounds, however, to subsequent studies to further elaborate on this concept and its clinical applicability. CONCLUSION: When RIC is applied in the experimental setting of testicular torsion, there is less evidence of hypoxic injury by histology and immunohistochemistry.

Molecular characterisation of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella spp. isolates at a tertiary-care centre in Lebanon.

The prevalence of bla CTX-M, bla TEM and bla SHV genes among extended-spectrum beta-lactamase (ESBL)-producing clinical isolates of Escherichia coli (n = 50) and Klebsiella spp. (n = 50) from Lebanon was 96%, 57% and 67%, and 40%, 82% and 84%, respectively. Genotyping revealed that the clonal diversity was unrelated to the presence of bla genes. Sequence analysis of 16 selected isolates identified the bla CTX-M-15, bla TEM-1, bla OXA-1 and six bla SHV genes, as well as the gene encoding the quinolone-modifying enzyme AAC(6')-Ib-cr. The genes encoding CTX-M-15 and AAC(6')-Ib-cr were carried on a 90-kb plasmid of the pC15-1a or pCTX-15 type, which transferred both ESBL production and quinolone resistance from donors to transconjugants.

Finger photoplethysmogram pulse amplitude changes induced by flow-mediated dilation.

This study was conducted to investigate the utility and efficacy of finger photoplethysmogram pulse amplitude (PPG-AC) in comparison with the standard Doppler ultrasound in assessing an endothelial function via flow-mediated dilation (FMD). High-resolution B-mode scanning of the right brachial artery (BA) of 31 healthy subjects aged 39.7 +/- 11.3 (range 22-64) years and 52 risk subjects aged 47.7 +/- 10.8 (range 30-65) years were performed before and after 4 min of upper arm occlusion. Concurrent with the ultrasound measurement (where color Doppler imaging was used to enhance arterial boundary detection), PPG signals were recorded from both index fingers for cross evaluation and comparison. Our results show that the finger PPG-AC exhibits a similar response to that of the well-known BA dilation: following the release of pressure (cuff around the BA), the PPG-AC increases abruptly before slowly decreasing toward the baseline. The peak PPG-AC is reached significantly faster than the peak FMD measured by ultrasound among healthy and risk groups (P < 0.001). The proposed technique using a finger photoplethysmogram can be applied in a rapid and non-invasive assessment of peripheral vascular functions as an alternative low-cost and less operator-dependent tool compared to ultrasound.

Electronic characterization of silicon intercalated chevron graphene nanoribbons on Au(111).

Electronic and thermal properties of chevron-type graphene nanoribbons can be widely tuned, making them interesting candidates for electronic and thermoelectric applications. Here, we use post-growth silicon intercalation to unambiguously access nanoribbons' energy position of their electronic frontier states. These are otherwise obscured by substrate effects when investigated directly on the growth substrate. In agreement with first-principles calculations we find a band gap of 2.4 eV.

Skin cancer caused by chronic arsenical poisoning--a report of three cases.

The association of arsenical poisoning with the development of skin cancer is well-known. In Malaysia, arsenic has been shown to coexist with tin in tin-mining land. Our preliminary investigation has shown that the level of arsenic in well water from a tin-mining area is high. We report 3 patients with cutaneous lesions typical of chronic arsenical poisoning such as hyperpigmentation, keratoses and skin cancer. These patients have positive histories of previous domicility in tin-mining areas. We conclude that these patients developed chronic arsenical poisoning from drinking well water polluted with arsenic from the tin-mining soil.

Adolescent's Attitudes Towards Health Warning Message on Cigarette Packs.

A total of 190 secondary four male school students from three schools in Kota Bharu were surveyed on their smoking habits and their attitudes towards the health warning messages on cigarette packs. There were 57 (30.0%) students who were current smokers, 45 (23.7%) students who were ex-smokers and 88 (46.3%) students who have never smoked cigarettes. Nearly all current and ex-smokers (95.1%) as well as non-smokers (94.3%) knew the wording of the health warning message currently displayed on cigarette packs. Almost all the students (95.3%) also knew where the warning message was placed. There were more ex-smokers and non-smokers (70.5%) compared to current smokers (50.0%) who felt that there should be different health warning messages and each should be displayed concurrently on different cigarette packs. The students felt that the current health message was not effective to motivate smokers to quit (score=2.25). Alternative messages which the students felt may be more effective were 'Smoking is dangerous for pregnancy' (score = 3.3), 'Cigarette smoke is dangerous for your child' (score=3.11) and 'Smoking can kill you' (score=3.08). The current health message "Smoking is dangerous for your health' is eighth with a score of only 2.64. The students felt that the least effective message was 'Cigarettes are drugs' (score=2.22). Most of the students (80.0%) felt that the health warning message should be placed at the front instead of on the side of the cigarette pack to be more effective.

Hoarseness as the sole symptom of an impending thoracic aneurysm rupture?

Unilateral vocal cord palsy secondary to thoracic aortic aneurysm is a rare occurrence. Direct compression of the enlarging thoracic aneurysm on the left recurrent laryngeal nerve causes neuronal injury of the nerve, which is manifested as hoarseness. We present a rare case of unilateral vocal cord palsy in a 60-year-old healthy gentleman caused by a large thoracic aortic aneurysm. This rare presentation, with a serious underlying pathology might be misdiagnosed or delayed. Therefore, it is important for us to have high index of suspicion in cases with a rare presentation such as this.

An elderly man with acute anterior neck pain and odynophagia after a meal.

The upper aerodigestive tract, specifically the cricopharyngeal area, is the most common site of foreign body impaction. Anatomically, this area is the first constriction of the oesophagus. Fish bones, one of the most common foreign bodies encountered in the throat, tend to get stuck in this area. The movement of this sharp-edged foreign body upon swallowing will induce odynophagia and an acute onset of neck pain. We report a case of a healthy elderly man who complained of sudden anterior neck pain and odynophagia after eating yellowtail scad fish.

Room-temperature ferromagnetism of all-epitaxial ß-Fe-Ge/diamond-Ge/ß-Fe-Ge trilayers.

We report on the first all-epitaxial ferromagnet/inorganic semiconductor/ferromagnet hybrid heterostructure that exhibits (i) a Ge barrier of diamond crystal structure, (ii) room-temperature ferromagnetic electrodes and (iii) very smooth interfaces. Both bottom- and top-Fe-Ge electrodes exhibit tiny in-plane magnetic anisotropies dominated by a magnetocrystalline contribution of six-fold symmetry originating from the hexagonal symmetry of the B82 (Ni2In) ß-Fe-Ge phase. A key result is the absence of any magnetic coupling between these soft-magnetic electrodes for Ge barrier thickness as low as ~2.5 nm, which allows us to easily tune the parallel and antiparallel magnetic alignments by applying suitably small magnetic fields. This confirms the beneficial use of H-surfactant in order to drastically reduce the roughness of the Ge barrier, as revealed by our scanning tunneling microscopy and transmission electron microscopy measurements. This new all-epitaxial ferromagnet/semiconductor hybrid system appears, therefore, to be a promising candidate for the realization of magnetic tunnel junctions with a single crystal semiconductor barrier that are fully compatible with Si-based technology.

Hoarseness as the sole symptom of an impending thoracic aneurysm rupture?

Unilateral vocal cord palsy secondary to thoracic aortic aneurysm is a rare occurrence. Direct compression of the enlarging thoracic aneurysm on the left recurrent laryngeal nerve causes neuronal injury of the nerve, which is manifested as hoarseness. We present a rare case of unilateral vocal cord palsy in a 60-year-old healthy gentleman caused by a large thoracic aortic aneurysm. This rare presentation, with a serious underlying pathology might be misdiagnosed or delayed. Therefore, it is important for us to have high index of suspicion in cases with a rare presentation such as this.

First detection and sequence analysis of the bla-CTX-M-15 gene in Lebanese isolates of extended-spectrum-beta-lactamase-producing Shigella sonnei.

The emergence in Shigella species of extended-spectrum beta-lactamases (ESBL) that impart resistance to third-generation cephalosporins is a growing concern world-wide. So far, however, ESBL-producing Shigella have only been reported seven times, albeit from seven different countries. In Lebanon, three ESBL-producing clinical isolates of S. sonnei were recovered from 30 cases of shigellosis diagnosed between July 2004 and October 2005. All three were found to be resistant to amoxycillin, cefotaxime, ceftazidime, aztreonam, trimethoprim/sulphamethoxazole, gentamicin, and kanamycin. Each harboured the bla-CTX-M gene, and the results of sequence analysis indicated this to be of the bla-CTX-M-15 type and encoded on a 70-kb plasmid, flanked by an insertion element (ISEcp1). The bla-TEM-1 gene was also detected on the chromosomes of two of the ESBL-producing isolates. Class-2 integrons containing dhfr1, aadA1 and sat1 genes were detected on the chromosomes of all three isolates but not on the plasmids. Fluoroquinolone-modifying factors [QnrA, QnrB, QnrS or AAC(6')-Ib-cr] were not detected. The results of RAPD analysis, combined with data on antimicrobial susceptibility, indicated that each isolate was unique. In conclusion, the emergence of ESBL-producing isolates of S. sonnei has been demonstrated for the first time in Lebanon. The resistance of these isolates to third-generation cephalosporins was mediated by the CTX-M-15 enzyme, which was plasmid-encoded.

Atopic eczema in a multiracial country (Malaysia).

A total of 14,342 patients with skin diseases who had attended either the National University of Malaysia skin clinic or a private dermatological office were analysed. Five hundred and thirty-four cases (3.7%) had atopic eczema, the prevalence being highest among the Malays (4.3%). The prevalence of atopic eczema among clinic attenders is lower in all three major Malaysian races when compared with studies from England.