Effect of a photoperiodic green light programme during incubation on embryo development and hatch process.

This study was conducted to evaluate the effect of a 12-h light, 12-h dark (12L : 12D) photoperiod of green light during day 1 to day 18 of incubation time, on embryo growth, hormone concentration and the hatch process. In the test group, monochromatic light was provided by a total of 204 green light-emitting diodes (522 nm) mounted in a frame which was placed above the top tray of eggs to give even spread of illumination. No light-dark cycle was used in the control group. Four batches of eggs (n=300/group per batch) from fertile Ross 308 broiler breeders were used in this experiment. The beak length and crown-rump length of embryos incubated under green light were significantly longer than that of control embryos at day 10 and day 12, respectively (P<0.01). Furthermore, green light-exposed embryos had a longer third toe length compared with control embryos at day 10, day 14 and day 17 (P=0.02). At group level (n=4 batches), light stimulation had no effect on chick weight and quality at take-off, the initiation of hatch and hatch window. However, the individual hatching time of the light exposure focal chicks (n=33) was 3.4 h earlier (P=0.49) than the control focal chicks (n=36) probably due to the change in melatonin rhythm of the light group. The results of this study indicate that green light accelerates embryo development and alters hatch-related hormones (thyroid and corticosterone), which may result in earlier hatching.

An insight into the heat and mass transfer mechanisms of eggshells hatching broiler chicks and its effects to the hatcher environment.

Thermodynamic study of incubated eggs is an important component in the optimisation of incubation processes. However, research on the interaction of heat and moisture transfer mechanisms in eggs is rather limited and does not focus on the hatching stage of incubation. During hatch, both the recently hatched chick and the broken eggshell add extra heat and moisture contents to the hatcher environment. In this study, we have proposed a novel way to estimate thermodynamically the amount of water evaporated from a broken eggshell during hatch. The hypothesis of this study considers that previously reported drops in eggshell temperature during hatching of chicks is the result remaining water content evaporating from the eggshell, released on the inner membrane by the recently hatched wet chick, just before hatch. To reproduce this process, water was sprayed on eggshells to mimic the water-fluid from the wet body of a chick. For each sample of eggshell, the shell geometry and weight, surface area and eggshell temperature were measured. Water evaporation losses and convection coefficient were calculated using a novel model approach considering the simultaneous heat and mass transfer profiles in an eggshell. The calculated average convective coefficient was 23.9 ± 7.5 W/m(2) °C, similar to previously reported coefficients in literature as a function of 0.5-1m/s air speed range. Comparison between measured and calculated values for the water evaporation showed 68% probability accuracy, associated to the use of an experimentally derived single heat transfer coefficient. The results support our proposed modelling approach of heat and mass transfer mechanisms. Furthermore, by estimating the amount of evaporated water in an eggshell post-hatch, air humidity levels inside the hatcher can be optimised to ensure wet chicks dry properly while not dehydrating early hatching chicks.

Presentation and management of mycotic pseudoaneurysm after kidney transplantation.

Pseudoaneurysms (PAs) developing at the site of vascular anastomosis after organ transplantation are a rare but serious complication. We report a series of 3 cases of PA observed in a single center over a period of 18 years. The mode of presentation was acute bleeding in 2 cases. In the third patient, who underwent combined kidney and pancreas transplantation, the PA on the renal graft was discovered by chance. Graft removal associated with iliac artery ligation and extra-anatomic femoro-femoral bypass represents the standard treatment. However, interposition of a venous homograft may allow preservation of inferior limb perfusion and possibly graft salvage.

E. coli heat labile toxin (LT) inactivation by specific polyphenols is aggregation dependent.

Recently, polyphenol extracts were suggested to inhibit binding of Escherichia coli heat labile enterotoxin (LT) to its intestinal receptor GM1. Therefore, polyphenols are promising feed or food supplements to combat enterotoxigenic infections. Little is known of the precise mechanism, or the type of polyphenol required. Here, seven different polyphenols were tested in vitro (1) for inhibition of LT binding to GM1 (GM1-ELISA), (2) for LT inhibitory activity in the cAMP Vero-cell assay, and (3) by testing the aggregating properties of polyphenols with LT using molecular weight exclusion membrane filters, and by centrifugation techniques. Results showed only three out of seven polyphenols, pentagalloylglucose (PGG), epigallocatechingallate (EGCG) and gallocatechingallate (GCG), to effectively inhibit binding of LT to GM1, and to inhibit induction of cAMP in Vero cells, and that PGG is the most effective. Blocking of the GM1 receptor is unlikely as a mechanism because pre-incubation of GM1 with polyphenols had no effect. Co-incubation of polyphenols with forskolin did not interfere with cAMP production in Vero cells, showing that polyphenol activity is not directly related to cAMP. It is concluded that the inhibitory activities of these three polyphenols may coincide with the formation of large (>100 kDa) LT-polyphenol aggregates. Enterotoxin inactivation appears to require a minimum of two galloyl moieties in polyphenol structure and the pentagalloyl PGG is the most effective.

Embryonic development and the physiological factors that coordinate hatching in domestic chickens.

Embryonic growth and development is influenced by both endogenous and exogenous factors. The purpose of this review is to discuss the critical stages of chick embryonic development in relation to functional maturation of numerous organ systems, the acquisition of thermoregulation, and the hatching process. In addition, the mechanism of hatching, including sound synchronization and hormonal and environmental stimulation, will be discussed. Finally, the importance of effective hatching synchronization mechanisms will also be highlighted.

The effect of enterotoxigenic Escherichia coli F4ab,ac on early-weaned piglets: a gene expression study.

Diarrhoea in neonatal and early-weaned piglets due to enterotoxigenic Escherichia coli-F4 (ETEC-F4) is an important problem in the pig farming industry. There is substantial evidence for a genetic basis for susceptibility to ETEC-F4 since not all pigs suffer from diarrhoea after an ETEC-F4 infection. A region on SSC13 has been found to be in close linkage to the susceptibility of piglets for ETEC-F4ab,ac. Potential candidate genes on SSC13 have been examined and although some polymorphisms were found to be in linkage disequilibrium with the phenotype, the causative mutation has not yet been found. In this study we are looking at the expression of porcine genes in relation to ETEC-F4ab,ac. With the aid of the Affymetrix GeneChip Porcine Genome Array we were able to find differentially expressed genes between ETEC-F4ab,ac receptor positive (Fab,acR(+)) piglets without diarrhoea and F4ab,acR(+) piglets with diarrhoea or F4ab,acR(-) animals. Since the susceptibility to ETEC-F4ab,ac was described as a Mendelian trait, it is not so surprisingly that only two differentially expressed genes, transferrin receptor (TFRC) and trefoil factor 1 (TFF1), came out of the analysis. Although both genes could pass for functional candidate genes only TFRC also mapped to the region on SSC13 associated with susceptibility for ETEC-F4, which makes TFRC a positional functional candidate gene. Validation by qRT-PCR confirmed the differential expression of TFRC and TFF1. In piglets without diarrhoea, the expression of both genes was higher in F4ab,acR(+) than in F4ab,acR(-) piglets. Similarly, TFRC and TFF1 expression in F4ab,acR(+) piglets without diarrhoea was also higher than in F4ab,acR(+) piglets with diarrhoea. Consequently, although both genes might not play a role as receptor for F4 fimbriae, they could be of great importance during an ETEC-F4 outbreak. An upregulation of TFRC can be a consequence of the piglets ability to raise an effective immune response. An elevation of TFF1, a protein involved in mucin formation, may also affect the piglet's capability to cope with ETEC bacteria, rather than being a receptor for its fimbriae.

Susceptibility of piglets to enterotoxigenic Escherichia coli is not related to the expression of MUC13 and MUC20.

Enterotoxigenic Escherichia coli (ETEC) is one of the most frequently isolated enteropathogens in production animals, especially pigs and calves. Economically, the swine industry is by far the most affected by infections with ETEC because of mortality, morbidity and decreased growth rate of newborn and early-weaned piglets. After ingestion by the animal, these bacteria attach themselves to specific receptors on the small intestinal epithelium by means of proteinaceous surface appendages, the fimbriae. The F4 fimbriae, which attach to the F4 receptor, are the most studied. The aim of our study was to investigate gene expression in the small intestine of piglets of MUC13 and MUC20 in relation to animals with a different treatment towards or a different reaction on ETEC-F4ac by means of quantitative reverse transcription chain reaction (qRT/PCR). MUC13 and MUC20 are positional candidate genes for this F4ac receptor and are located in the region on SSC13q41 that segregates with the susceptibility to ETEC-F4ac. The condition of the small intestine is crucial when examining expression differences between different samples. Therefore, the expression of two genes, fatty-acid binding protein 2, intestinal (FABP2) and pancreatitis-associated protein (PAP), now known as regenerating islet-derived 3 alpha (REG3A) in the small intestine was simultaneously checked. FABP2, a standard for epithelial content, reflects the state of damage, whereas REG3A is a measure for inflammation in the small intestine. The four different substudies presented here suggest that expression of MUC13 and MUC20 is not related to the susceptibility of piglets to ETEC-F4ac.

Aneurysm of the splenic artery which arises from the superior mesenteric artery: a case report.

Aneurysm of the splenic artery which arises from the superior mesenteric artery is a very rare condition with less than twenty cases described in the literature. Most of the time, it is asymptomatic and the diagnosis is fortuitous, but the patient can feel epigastric or left upper quadrant discomfort. One can palpate an abdominal mass or hear an abdominal systolic murmur. The most fatal presentation is the life-threatening rupture. We report the case of a 41-year-old woman presenting an aneurysm of the splenic artery originating from the superior mesenteric artery treated surgically by simple aneurismal resection with neither arterial reconstruction nor splenectomy. The different treatment modalities are discussed, taking into account the presence of the vascular malformation.

Otitis media microbes: culture, PCR, and confocal laser scanning microscopy.

OBJECTIVES: To assess the presence of middle ear pathogens in nasopharynx (NP), middle ear fluid (MEF), and middle ear mucosal swabs (MES) of 14 patients undergoing middle ear surgery. METHODOLOGY: Bacteria were assessed by culture and species specific PCR. Biofilm was investigated by confocal laser scanning microscopy (CLSM) of middle ear biopsies (MEBs). RESULTS: Bacteria were absent in CLSM of MEBs in three of the four closed and healthy middle ears. Bacteria occurred in the ear with a foreign body (middle ear prosthesis), which showed localized living and dead bacteria, indicating biofilm. Bacterial growth was present in ten patient ears, but biofilm occurred in only one patient. CLSM indicated biofilm in the middle ear of two patients for whom PCR detected Haemophilus influenzae in the MEF. The three classical pathogens could frequently be found in the nasopharynx, by culture and PCR, but not from the middle ear. Alloiococcus otitidis was detected in the MEF of all five patients with open inflamed ears, though virtually absent from the nasopharynx. Pseudomonas aeruginosa was present in seven. It was the only pathogen found on several occasions in all three locations in one patient. CONCLUSIONS: This study confirms the association of H. influenzae with middle ear biofilm, and indicates a potential role of P. aeruginosa in middle ear inflammation and biofilm formation. Biofilm does not seem to cause inflammation. It is unclear whether the predominance of A. otitidis in chronically inflamed open middle ears indicates a pathogenic or contaminant role for this organism.

Stump pressure and somatosensory evoked potentials for predicting the use of shunt during carotid surgery.

The aim of this study is to compare measurement of stump pressure (SP) and somatosensory evoked potentials (SSEP) made during carotid surgery as criteria upon which to base the decision whether or not to use a shunt. We included 288 patients who underwent for carotid surgery under general anaesthesia. We performed 247 endarterectomies with patch closure (85.7%), 25 carotid transsection with reimplantation (8.7%), and 16 carotid bypasses (5.6%). SSEP monitoring showed no modification in 225/288 patients (78.1%), moderate modification in 32/288 patients (11.1%), and severe modification in 31/288 patients (10.8%). Shunt was used if there was moderate or severe SSEP modification in response to carotid clamping, which represents 63 patients in our series. A shunt was used in 47/288 patients (16.3%). In 16 patients, despite SSEP modifications, the shunt was not used because these SSEP modifications occurred only in the last minutes of the procedure just before off clamping the carotid. The mean SP for all patients was 51 mm Hg. In the shunted patients, the mean SP was 33 mm Hg. Variation of SP was correlated with the SSEP modifications. There was just one perioperative stroke in this series (1/288 = 0.3%). We concluded that the threshold of SP below which shunting is indicated in our study was 44 mm Hg with 81% sensibility and 68% specificity.

Ischemic cerebral lesions after carotid surgery and carotid stenting.

OBJECTIVES: To evaluate the risk of new ischemic cerebral lesions after carotid endarterectomy and carotid stenting and their clinical significance. METHODS: Prospective and non-randomized single-center study including 121 patients with symptomatic and asymptomatic significant carotid stenosis. 60 patients were treated by surgery and 61 treated by carotid stenting. Stenting was restricted to patients at high risk for surgery. Neurological examination and Diffusion-Weighted Cerebral Magnetic Resonance (DW-MRI) were performed before and after each procedure. The presence, location and volume of new cerebral lesions were determined. RESULTS: In the surgical group, 2 minor strokes were registered. DW-MRI showed new lesions in 7 patients (11.6%). All except one were located in the ipsilateral anterior circulation. In the stenting group, 1 minor stroke and 1 occurrence of quadranopsia were registered. DW-MRI showed new lesions in 26 patients (42.6%). 10 of these patients (38.4%) had lesions in the contralateral hemisphere and 7 patients (26.9%) in the posterior circulation. Deficits are found in patients with higher lesion volumes. CONCLUSIONS: Cerebral ischemic lesions are significantly (p<0.0001) more frequent after carotid stenting than after endarterectomy. The majority of these lesions have no immediate clinical implication, but more specific tests are needed to evaluate their exact significance.

Intra-operative acute leg ischaemia after free fibula flap harvest for mandible reconstruction.

Osteosarcomas of the cranial bones need a large surgical radical resection. The best option to reconstruct mandible defect after resection is the free fibula flap. In our patient an acute ischaemic leg occurred just after the free fibula flap harvest for mandible reconstruction. The abnormal distribution of the calf arteries leads to catastrophic consequences. The peroneal artery could be the main dominant artery of the leg in a small number of patients. We reported an extremely rare case of "peronea magna", described in less than 0.2% of the global population. A careful pre-operative workup of the calf vessels is required in all the patients who need free fibula flap harvest.

Epidemiology of Pseudomonas aeruginosa in a cystic fibrosis rehabilitation centre.

Pseudomonas aeruginosa is the leading pathogen in cystic fibrosis (CF) lungs. Since there is great concern about clonal spread in CF centres, this study examined the P. aeruginosa genotypes of colonised residents of a CF rehabilitation centre. The isolates from the sputum of 76 P. aeruginosa-colonised patients were genotyped by fluorescent amplified fragment length polymorphism on arrival and departure. A total of 71 different P. aeruginosa genotypes were identified from 749 isolates. Forty-nine patients had one genotype, 20 had two genotypes and seven had three. Forty-four patients had one or more genotypes in common with other patients (i.e. cluster types). Thirty-two patients were colonised by a single genotype not shared by any other patient. Thirty-eight of the 44 patients with a cluster type already carried their cluster type strain(s) on arrival. Patient-to-patient transmission could not be excluded for eight patients. For five of these, this infection was transient. None of the environmental P. aeruginosa isolates had a genotype similar to the patients' genotypes. In summary, most patients were colonised by only one or two P. aeruginosa genotypes and the risk of persistent patient-to-patient transmission was low during the study period (4%). Most patients with a cluster-type strain carried this strain on arrival, indicating that transmission could have happened in the past. No environmental contamination could be established.

Functional classification of aortic root/valve abnormalities and their correlation with etiologies and surgical procedures.

PURPOSE OF REVIEW: Patients with aortic root pathology may benefit from 'valve-conservation' surgery although application of this philosophy is limited by a lack of 'standardized' surgical techniques. A functional classification of aortic root and valvular abnormalities has been developed in 260 patients and correlated with the etiology of the pathologic process and the surgical procedure performed. Early outcome was assessed using hospital records and medium-term follow-up by cardiological review. RECENT FINDINGS: From January 1995 until March 2001, 260 patients were operated on for aortic root pathology using valve-conserving surgical techniques. Hospital mortality was 2%; intra-operative echocardiography showed residual aortic regurgitation (Grade 1-2) in 11%, none in the remaining patients. Follow-up at a mean of 20 months (87% of patients) showed trivial or Grade 1 aortic regurgitation in 80%. SUMMARY: Application of a simple functional classification for aortic root pathology and aortic valve disease allows the logical application of 'valve-conserving' surgical procedures with excellent early and medium-term results.

Investigation of the effect of the coronal restoration quality on the composition of the root canal microflora in teeth with apical periodontitis by means of T-RFLP analysis.

AIM: To investigate the effect of the radiographic and clinical quality of coronal restorations on the composition of the root canal flora of teeth with necrotic pulps and teeth with root fillings associated with apical periodontitis. METHODOLOGY: Twenty-eight necrotic pulps and 35 root filled canals with signs of apical periodontitis were studied. Both the coronal filling (presence of radiographically or clinically deficient margins and/or secondary caries) and the root filling (homogeneity and length) were scored. Bacterial root canal samples were taken with sterile paper points under rubber dam and using measures to prevent contamination. A DNA-based nonculture bacterial identification technique was used, namely terminal restriction fragment length polymorphism (T-RFLP) analysis. RESULTS: Twelve samples were negative for bacterial DNA. A total of 33 different terminal restriction fragments (TRFs) were detected. The Fusobacterium nucleatum/Streptococcus mitis group was the most frequently encountered TRF. The mean number of TRFs per necrotic pulp was 6.2 and 5.8 for the groups with acceptable and unacceptable coronal restorations, respectively. This difference was not significant. In the root filled group, these values (respectively, 5.2 and 8.6) were statistically significantly different (P < 0.05). The following parameters in root filled teeth had no significant influence on the mean numbers of TRFs detected: the length and homogeneity of the root filling and the type of tooth (anterior-premolar-molar). CONCLUSION: T-RFLP allowed the rapid assessment of bacterial biodiversity in root canal samples. The technique revealed the presence of bacteria that have rarely been described in the root canals of teeth with apical periodontitis. Biodiversity in the root filled group was high, as compared with culture-dependent studies where monoinfections were more frequently reported. Only in root filled teeth did defective coronal restorations have a statistically significant influence on the mean numbers of detected TRFs per sample.

Repair of aortic valve prolapse: experience with 44 patients.

OBJECTIVES: In regurgitant tricuspid aortic valves, cusp prolapse may be isolated or associated with dilatation of the proximal aorta. Newly appearing cusp prolapse can also appear after an aortic valve sparing operation (AVSO) and be responsible for residual aortic regurgitation. In this report, we describe our experience in repairing prolapsing aortic cusps in 44 patients with aortic regurgitation. METHODS: Between 1996 and 2003, 260 patients had aortic valve repair or valve sparing procedures in our department. All patients had peri-operative TEE. Prolapse of one or more of the aortic cusps was identified by TEE and confirmed by careful surgical inspection before and after valve sparing surgery. Forty-four patients with cusp prolapse were identified. Fifteen had an isolated prolapse, with a normal root (group I), 18 had cusp prolapse associated with dilatation of the proximal aorta (group IIa), and 11 had a newly appearing prolapse after AVSO (group IIb). Correction of the prolapsing cusp was achieved by either free edge plication, triangular resection or resuspension with PTFE. This procedure was associated with an aortic annuloplasty in group I, and with AVSO in groups II and III. RESULTS: Post-operative TEE showed AR trivial or grade I regurgitation. At a mean of 23 months follow-up, one patient with recurrent regurgitation required an aortic valve replacement with a homograft. All remaining patients were in NYHA class I or II. Echocardiography confirmed the durability of the valve repair. CONCLUSIONS: Among the common causes of aortic regurgitation, isolated cusp prolapse is frequent and is amenable to surgical repair with excellent mid-term results. In particular, in patents who are potential candidates for AVSO, identification and correction of an associated prolapse, either pre-existing or secondary to the AVSO procedure, may further extend the indications for this technique, increase its success rates and improve its long-term outcome.