bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation and identification of Alicyclobacillus acidocaldarius by 16S rDNA from mango juice and concentrate
Authors: Gouws Pieter A. , Gie Lindy , Pretorius Ashley , Dhansay Nadeem
Published: July 2005

In this study we investigate the spoilage of ultra high temperature UHT mango juice as well as a carbonated fruit juice blend to identify organisms contributing to the spoilage. The mango concentrate, the final product, as well as the other ingredients used during manufacturing, were tested for the presence of Alicyclobacillus by polymerase chain reaction (PCR) and sequencing analyses. Microbiological examination of the mango pureé and spoiled fruit juices, using YSG agar [yeast extract 2 g, glucose 1 g, soluble starch 2 g, pH 3.7 (adjust with 2N H2SO4), H2O 1000 mL, bacto agar 15 g] incubated at 55 °C, detected sporeforming, acid dependent and thermotolerant bacteria. The hyper variable region of the 16S rDNA was amplified. The nucleotide sequence of the PCR fragments was determined using the ABI Prism 310 automated DNA sequencer and the collected sequencing data were analysed and compared with the non‐redundant database using NCBI‐BLAST. Alicyclobacillus acidocaldarius were isolated and identified by 16S rDNA gene sequences analyses. The results indicated that the mango purèe, as well as the final product of mango juice and the fruit juice blend, were positive for Alicyclobacillus. The preventative measures of low pH, pasteurization of mango juice and the subsequent use of aseptic packaging were not regarded as sufficient to prevent the outgrowth of Alicyclobacillus spoilage organisms.
Reactions with phenolic substances can induce changes in some physico‐chemical properties and activities of bromelain – the consequences for supplementary food products
Authors: Rohn Sascha , Rawel Harshadrai M. , Röber Miriam , Kroll Jürgen
Published: July 2005

Bromelain was allowed to react with phenolic compounds. The activity and selected physico‐chemical properties of the resulting derivatives were characterized. In vitro experiments showed that the proteolytic activity of bromelain was inhibited. Bromelain also serves as a food protein, because food stuffs based on pineapple contain relatively high concentrations of bromelain. In vitro digestion of bromelain derivatives with the main proteolytic enzymes of the gastrointestinal tract was also adversely affected. A covalent attachment of the phenolic compounds was identified at the tryptophan, free amino (lysines and N‐terminal) and thiol groups of bromelain. A decrease in solubility of the derivatives was observed. The isoelectric point was shifted to lower pH values and high molecular weight fractions were identified. All effects observed depended on the reactivity of the phenolic substances. Two supplementary food products containing both bromelain and quercetin were also tested in terms of their proteolytic activity and digestibility.
Kanamycin reveals the role played by glutamate receptors in shaping plant resource allocation
Authors: Dubos Christian , Willment Janet , Huggins David , Grant Guy H. , Campbell Malcolm M.
Published: July 2005

Ionotropic glutamate receptors (iGluRs) play important roles in neurotransmission in animals. There is growing evidence that iGluRs also play important roles in plants. Using a chemical genetics approach, which combined a pH‐homeostasis mutant of Arabidopsis thaliana (de‐etiolated3), several different iGluR agonists, molecular modelling, and reporter gene expression in transgenic plants, we provide evidence that iGluR agonism can induce dramatic changes in plant development and metabolism. Systematic hypothesis testing revealed a signalling circuit that integrates amino acid and sugar signals to affect elongation growth and the deposition of carbon into starch and lignins. The data show that aminoglycoside antibiotics, such as kanamycin, and polyamines impinge upon this circuit. These findings provide a mechanism for the conversion of amino acid and sugar signals into an appropriate response at the gene expression level, and underline the similarities in iGluR agonism between animals and plants.
The Arabidopsis ROCK‐N‐ROLLERS gene encodes a homolog of the yeast ATP‐dependent DNA helicase MER3 and is required for normal meiotic crossover formation
Authors: Chen Changbin , Zhang Wei , Timofejeva Ljudmilla , Gerardin Ylaine , Ma Hong
Published: July 2005

Recent studies in Saccharomyces cerevisiae have unveiled that meiotic recombination crossovers are formed by two genetically distinct pathways: a major interference‐sensitive pathway and a minor interference‐insensitive pathway. Several proteins, including the MSH4/MSH5 heterodimer and the MER3 DNA helicase, are indispensable for the interference‐sensitive pathway. MSH4 homologs have been identified in mice and Arabidopsis and shown to be required for normal levels of crossovers, suggesting that the function of MSH4 may be conserved among major eukaryotic kingdoms. However, it is not known whether an MER3‐like function is also required for meiosis in animals and plants. We have identified an Arabidopsis gene that encodes a putative MER3 homolog and is preferentially expressed in meiocytes. T‐DNA insertional mutants of this gene exhibit defects in fertility and meiosis. Detailed cytological studies indicate that the mutants are defective in homolog synapsis and crossover formation, resulting in a reduction of bivalents and in the formation of univalents at late prophase I. We have named this gene ROCK‐N‐ROLLERS (RCK) to reflect the mutant phenotype of chromosomes undergoing the meiotic ‘dance’ either in pairs or individually. Our results demonstrate that an MER3‐like function is required for meiotic crossover in plants and provide further support for the idea that Arabidopsis, like the budding yeast, possesses both interference‐sensitive and insensitive pathways for crossover formation.
Overexpression of ADC2 in Arabidopsis induces dwarfism and late‐flowering through GA deficiency
Authors: Alcázar Rubén , García‐Martínez José L. , Cuevas Juan C. , Tiburcio Antonio F. , Altabella Teresa
Published: July 2005

We have obtained Arabidopsis thaliana transgenic plants constitutively overexpressing ADC2, one of the two genes encoding arginine decarboxylase (ADC) in Arabidopsis. These plants contained very high levels of putrescine (Put) but no changes were observed in spermidine and spermine contents. The results obtained from quantification of free and conjugated polyamines suggest that conjugation may be a limiting step for control of Put homeostasis within a non‐toxic range for plant survival. Transgenic plants with increased levels of ADC2 transcript and elevated Put content showed dwarfism and late‐flowering, and the phenotype was rescued by gibberellin A3 (GA3) application. The contents of bioactive GA4 and GA1, and of GA9 (a precursor of GA4), as well as the levels of AtGA20ox1, AtGA3ox1 and AtGA3ox3 transcripts (quantified by real‐time PCR) were lower in the ADC2 overexpressor plants than in the wild type. No change in the expression of genes encoding earlier enzymes in the GA biosynthesis pathway was detected by microarray analysis. These results suggest that Put accumulation affects GA metabolism through the repression of biosynthetic steps catalyzed by GA 20‐oxidase and GA 3‐oxidase.
Direct genotyping of the poplar leaf rust fungus, Melampsora medusae f. sp. deltoidae, using codominant PCR‐SSCP markers
Authors: Bourassa M. , Bernier L. , Hamelin R. C.
Published: July 2005

Two anonymous DNA markers that are revealed by single‐strand conformational polymorphism (SSCP) analysis were developed for detection of polymorphisms in Melampsora medusae f. sp. deltoidae (Mmd). Mono‐uredinial isolates of Mmd were first obtained, DNA was extracted from urediniospores and random amplified polymorphic DNA (RAPD) products of eight mono‐uredinial isolates were separated on a SSCP gel to identify differences among them. Bands representing putative polymorphic loci among the eight isolates tested were excised from the SSCP gel and re‐amplified by polymerase chain reaction (PCR), and then cloned and sequenced. A primer pair was designed to amplify a DNA fragment of a size suitable for SSCP analysis (<600 bp) for two out of three DNA fragments sequenced. Each set of primers amplified a PCR product for all eight isolates that were initially used to generate them and the resulting PCR products were analysed by SSCP. Polymorphisms among isolates were identified for both putative loci. The two primer pairs amplified a PCR product of the expected size on an additional 32 mono‐uredinial isolates of Mmd tested. From the overall 40 mono‐uredinial isolates tested, 5 and 11 alleles were detected, and 12 and 34 isolates showed to be heterozygous, as indicated by the presence of more than two bands on the SSCP gel, at loci A and B, respectively. The primer pairs were tested for specificity against 106 fungal isolates belonging to various taxa, including other rusts, and against DNA extracted from greenhouse‐grown healthy poplar leaves. DNA amplification products of the expected size were obtained only when Mmd DNA was present. Optimization of PCR conditions with these two primer pairs allowed genotyping directly from single uredinia extracted from infected leaves, thus alleviating the need to culture the fungus to characterize individuals, hence making it possible to process large numbers of samples for population studies.
The effect of nitrogen fertilization on fungistatic phenolic compounds in roots of beech (Fagus sylvatica) and Norway spruce (Picea abies)
Authors: Tomova L. , Braun S. , Flückiger W.
Published: July 2005

The effect of nitrogen fertilization on fungistatic phenolic compounds in fine roots of beech and Norway spruce growing in afforestation plots was analysed. The plots were situated at two sites in Switzerland on acidic soil with low base saturation. For 9 years, the trees have been treated with dry ammonium nitrate to give 0, 10, 20, 40, 80, 160 kg N ha−1 year−1, respectively. The phenolic compounds responded differently to fertilization. Fine roots of beech showed a significant decrease of (−)‐epicatechin and piceatannol with increasing nitrogen fertilization. The concentration of protocatechuic acid was increased with fertilization. Roots of fertilized Norway spruce showed significantly decreased concentrations of 4‐hydroxyacetophenone and piceatannol. The mycelial growth of three isolates each of Heterobasidion annosum s.l. and Cylindrocarpon destructans was tested on agar media containing various phenolic compounds in concentrations found in fine roots of Norway spruce (Picea abies) and beech (Fagus sylvatica). All three H. annosum isolates were inhibited by p‐coumaric acid and (−)‐epicatechin. Two isolates were inhibited by another four phenolic compounds (p‐hydroxybenzoic acid, 4‐hydroxyacetophenone, piceatannol and protocatechuic acid), one by (+)‐catechin. Two of three C. destructans isolates were inhibited by all phenolic compounds except for (+)‐catechin which affected only one isolate, one isolate did not respond at all.
Longitudinal findings of acute macular neuroretinopathy with multifocal electroretinogram and optical coherence tomography
Authors: Chan Wai‐Man , Liu David TL , Tong Jian‐Ping , Law Ricky WK , Lam Dennis SC
Published: July 2005

Abstract

A 34‐year‐old woman, with preceding flu‐like febrile illness, developed acute macular neuroretinopathy in her left eye with typical reddish brown macular lesions and a dense paracentral scotoma. Her condition was evaluated with multifocal electroretinogram and optical coherence tomography in her acute and recovery phases. The findings assist ophthalmologists striving for better understanding and diagnosis of acute macular neuroretinopathy.
Transscleral diode laser therapy for cyclodialysis cleft induced hypotony
Authors: Amini Heydar , Razeghinejad Mohammad Reza
Published: July 2005

Abstract

In order to evaluate the efficacy of transscleral diode laser therapy for treatment of cyclodialysis cleft associated with ocular hypotony, transscleral diode laser therapy was used in two patients with cyclodialysis cleft. It was applied over the cleft area in two rows of 14 applications in a post‐traumatic patient and of 8 applications in a post‐trabeculectomy patient at a power setting of 2500 mW and duration of 2000 msec. The clefts were closed with restoration of normal intraocular pressure and recovery of visual function in both patients. Transscleral diode laser therapy seems to be a safe, simple and non‐invasive method for closure of the cyclodialysis clefts, especially in patients inappropriate for argon laser photocoagulation and those with opaque cornea.
Clinical presentation of retinoblastoma in Eastern Nepal
Authors: Badhu Badri , Sah Shatrughan P , Thakur Sanjay KD , Dulal Sunu , Kumar Sandeep , Sood Archana , Das Hrishikesh , Sah Rabindra P
Published: July 2005

Abstract

Background:  The purpose of the present study was to determine modes of presentation of retinoblastoma and the association between proptosis with orbital extension and histopathologically detectable optic nerve infiltration by the tumour.

Methods:  Clinical records and histopathological reports of patients with retinoblastoma were studied retrospectively. The work was undertaken at a tertiary care hospital in eastern Nepal during the period from September 1995 to August 2002.

Results:  A total of 43 patients with retinoblastoma were studied. Among them unilateral involvement was found in 39 patients (90.70%) and bilateral involvement in four patients (9.30%). The mean age of presentation was 3.04 ± 1.80 years (95% confidence interval = 2.49–3.59). The commonest mode of presentation was proptosis with orbital extension in 19 eyes (40.42%) followed by leucokoria in 14 eyes (29.78%). Histopathological reports of 42 eyes (one patient died shortly after admission and did not have an autopsy) confirmed the diagnosis of retinoblastoma and revealed that the optic nerve cut section had been infiltrated in 18, of which 16 had the clinical finding of proptosis with orbital extension. This was statistically significant (relative risk = 21.33, P < 0.001).

Conclusion:  The commonest mode of presentation of retinoblastoma in Nepal is proptosis. Presence of proptosis with orbital extension is associated with optic nerve cut end infiltration by the tumour. The diagnosis or presentation of retinoblastoma in Nepal is delayed and there is tremendous scope for improvement in its management.
Tractional retinal detachment in Usher syndrome type II
Authors: Rani Alka , Pal Nikhil , Azad Raj Vardhan , Sharma Yog Raj , Chandra Parijat , Vikram Singh Deependra
Published: July 2005

Abstract

Retinal detachment is a rare complication in patients with retinitis pigmentosa. A case is reported of tractional retinal detachment in a patient with retinitis pigmentosa and sensorineural hearing loss, which was diagnosed as Usher syndrome type II. Because of the poor visual prognosis, the patient refused surgery in that eye. Tractional retinal detachment should be added to the differential diagnoses of visual loss in patients with retinitis pigmentosa.
Epiretinal membrane surgery with or without internal limiting membrane peeling
Authors: Kwok Alvin KH , Lai Timothy YY , Yuen Kenneth SC
Published: July 2005

Abstract

Background:  The purpose of the present paper was to evaluate the visual outcome and recurrence rate of epiretinal membrane (ERM) formation following vitreoretinal surgery with and without internal limiting membrane (ILM) peel.

Methods:  The medical records of 42 consecutive patients who underwent surgery for macular ERM by a single surgeon were reviewed. All patients underwent pars plana vitrectomy and ERM removal with a subset undergoing ILM peel. Recurrence of macular ERM within 18 months and the final visual outcome after surgery were compared between patients with and without ILM removal.

Results:  Twenty‐five patients (59.5%) underwent ERM surgery with ILM peeling and 17 patients (40.5%) underwent ERM surgery without ILM peeling. The mean preoperative logMAR visual acuity was 0.77 and 0.96 for the ILM peeling and non‐ILM peeling groups, respectively. Visual acuity improved significantly in both the ILM and non‐ILM peeling groups after ERM surgery (P < 0.001 and P = 0.003, respectively). Eighteen months after surgery, 3/17 eyes without ILM peeling (17.6%) developed recurrent macular ERM, compared with none of the 25 eyes with ILM peeling (log–rank test, P = 0.030).

Conclusions:  Internal limiting membrane removal during macular ERM surgery may minimize the recurrence of ERM, without adverse visual outcome. Further controlled prospective studies are needed to determine the role of ILM peeling in ERM surgery.
Visual outcomes following vitrectomy and peeling of epiretinal membrane
Authors: Wong James G , Sachdev Nitin , Beaumont Paul E , Chang Andrew A
Published: July 2005

Abstract

Background:  Visual outcomes of patients following vitrectomy and peeling of visually significant epiretinal membranes were assessed to determine the influence of specific perioperative factors and surgical complications on final visual acuity and functional vision.

Methods:  In an unmatched, consecutive surgical series, vitrectomy and membrane peeling were performed on 125 eyes of 123 patients with visually significant macular epiretinal membranes. Patients were followed for 6–36 months. Visual outcome measures included postoperative logMAR visual acuity, change in visual acuity and functional vision tasks evaluated by questionnaire. Perioperative factors including duration of symptoms, preoperative visual acuity, aetiology, membrane type and leakage on fundal fluorescein angiogram were correlated with final visual outcomes.

Results:  Visual acuity improved by a mean of 0.31 Â± 0.21 units (three lines of vision). In 104 cases (83%), visual acuity improved in patients by two lines or more, with 20 cases (16%) having unchanged acuity and one case (1%) having worse acuity. Ninety‐three per cent of interviewed cases reported improvement in functional vision, especially reduction of distortion. Cataract was observed in 52 cases (52% of phakic eyes) postoperatively compared with 19 cases (19%) preoperatively. Postoperative visual acuity correlated with preoperative visual acuity. Patients with worse preoperative vision recorded greater visual improvement following surgery. No other perioperative factors were found to have a prognostic value in this study.

Conclusion:  Epiretinal membrane peeling improves vision in the majority of patients with significant symptoms, even if preoperative visual acuity is not substantially reduced. Surgery improves functional vision including metamorphopsia not measurable by visual acuity, and thus assessment of functional vision should be included in surgical case planning.
Amadeus microkeratome: experience with the first 2000 cases and lessons learned
Authors: Chan Colin CK , Moshegov Con N
Published: July 2005

Abstract

Background:  To assess the safety and efficacy of the Amadeus microkeratome and to report on lessons learnt in optimizing results from its use.

Methods:  A retrospective review of the flap‐related complications of 2000 laser in situ keratomileusis (LASIK) procedures performed by one surgeon using the Amadeus microkeratome (AMO, Irvine, CA, USA) was conducted. One hundred consecutive cases had preoperative and intraoperative pachymetry to evaluate the relationship between flap thickness, corneal thickness and reuse of the blade.

Results:  There were 35 cases of minor epithelial defects (1.8%) and four eyes with major epithelial defects (0.2%). There were no cases of suction loss, buttonholes, or incomplete or damaged flaps. There were four free caps (0.2%). Twenty‐five cases had minor wrinkles and two cases had significant folds requiring relifts. Thinner corneas resulted in thinner flaps (P < 0.0001). Reuse of the blade resulted in thinner flaps (P = 0.0001).

Conclusion:  The Amadeus is a safe and reliable microkeratome. Although short, there is a learning curve with use of the instrument. Corneal thickness and reuse of the blade affect flap thickness.
Cataract surgery in patients with age‐related maculopathy: preoperative diagnosis and postoperative visual acuity
Authors: Pham Thuan Q , Wang Jie J , Maloof Anthony , Mitchell Paul
Published: July 2005

Abstract

Purpose:  To report the reliability in detecting age‐related maculopathy (ARM) lesions before cataract surgery and postoperative visual acuity (VA) in cataract surgery patients with ARM.

Methods:  Medical records of surgical patients in a large public hospital, west of Sydney, were reviewed retrospectively. Detection of ARM lesions was compared before and after surgery to determine sensitivity and specificity of preoperative diagnoses. Postoperative VA was assessed 4 weeks after surgery.

Results:  Data were available for 721/784 eyes (92.0%) of 656 patients aged 60 years or older. ARM lesions were detected in 98 eyes (13.6%) before and 92 eyes (12.8%) after  surgery.  Sensitivities  for  detecting  late  ARM  lesions, soft drusen and retinal pigment epithelium abnormalities preoperatively were 100%, 94% and 69%, respectively. Corresponding specificities were 100%, 100% and 77%, respectively. Postoperative VA achieved or remained 6/12 or better in 81.6% of eyes.

Conclusion:  A high sensitivity and specificity in detecting late ARM lesions and soft drusen preoperatively, and a good postoperative VA outcome is achievable in patients with preoperative early ARM lesions.
Two‐year results of laser treatment for retinopathy of prematurity at a single neonatal intensive care unit
Authors: Essex Rohan W , Carden Susan M , Elder James E
Published: July 2005

Abstract

Purpose:  To present the 2‐year results of all patients receiving laser treatment for retinopathy of prematurity (ROP) at a single institution over a 9.5‐year period. To establish the frequency of threshold ROP.

Methods:  Consecutive case series. All patients who had laser treatment for ROP at The Royal Women's Hospital, Melbourne, Australia, between January 1992 and July 2001 were prospectively recorded in a database. Their medical charts were retrospectively reviewed. Baseline birthweight, gestational age at birth, timing of treatment, and ROP severity at treatment were recorded. The main outcome measures were visual acuity (significantly reduced or not), anatomic outcome and refractive error at 2 years of age (corrected for the degree of prematurity).

Results:  A total of 107 eyes of 57 babies were treated with laser photocoagulation. Four children did not survive for follow‐up, and 2‐year follow‐up data were available for 38 children (67%, 71 treated eyes). Average duration of follow‐up was 26 months. Two‐year visual acuity was significantly reduced in 12/71 (17%) treated eyes, and 3/38 children (8%) had significantly reduced vision in both eyes. An anatomical outcome of macular fold or worse was observed in 8/71 eyes (11%). Mean 2‐year spherical equivalent refractive outcome was only minimally myopic (−0.6 D).

Conclusion:  Visual, anatomic and refractive outcomes after laser treatment for ROP were favourable, confirming that laser photocoagulation is an effective treatment for severe ROP.
Eyelid schwannoma in a male adult
Authors: Siddiqui MA Rehman , Leslie Thorfinn , Scott Christopher , MacKenzie James
Published: July 2005

Abstract

Schwannomas (neurilemmomas) are benign tumours of peripheral nerves arising from Schwann cells. These tumours along with neurofibromas form the two most common primary peripheral nerve tumours. Solitary lesions can occur sporadically in the general population but multiple neurofibromas are distinctive feature of neurofibromatosis type 1 and bilateral acoustic schwannomas are a feature of neurofibromatosis type 2. Schwannomas of ophthalmic interest are rare although they have been reported in relation to the orbit, and infrequently uveal tract and conjunctiva. Isolated eyelid schwannomas appear infrequent; only four cases in adults and one in a child in the published literature have been found. Herein, a case of eyelid schwannoma in a 53‐year‐old man is described.
Hyperpolarization‐activated (Ih) currents in auditory brainstem neurons of normal and congenitally deaf mice
Authors: Leao Richardson N. , Svahn Katarina , Berntson Amy , Walmsley Bruce
Published: July 2005

We have investigated the membrane properties of brainstem auditory neurons in a mouse model of congenital deafness (dn/dn). Whole‐cell recordings were made from visualized neurons in slices of the medial nucleus of the trapezoid body (MNTB) and anteroventral cochlear nucleus (AVCN). We have recently demonstrated that MNTB neurons in deaf mice are more excitable than in normal mice, due in part to a reduced expression of low‐threshold potassium currents. In this study, we have examined the contribution of hyperpolarization‐activated (Ih) channels to the membrane properties of MNTB and AVCN neurons. Our results show thatIhis larger in MNTB neurons from deaf mice than in normal mice. In contrast, no significant differences were found inIhor excitability between AVCN bushy cells fromdn/dnand normal mice. Experimental evidence and neuronal modelling suggests that, in the MNTB of normal mice, a small contribution ofIhhelps to reduce temporal summation of synaptic potentials. A largerIhin neurons from deaf mice has a much greater effect in reducing temporal summation of synaptic potentials, counteracting to some extent the greater excitability of these cells. Our results provide further insight into the role of activity during development in regulating the membrane and firing properties of central neurons.
Inducible neuronal expression of transgenic TGF‐β1 in vivo: dissection of short‐term and long‐term effects
Authors: Ueberham Uwe , Ueberham Elke , Brückner Martina K. , Seeger Gudrun , Gärtner Ulrich , Gruschka Hildegard , Gebhardt Rolf , Arendt Thomas
Published: July 2005

Various chronic neurological diseases are associated with increased expression of transforming growth factor‐beta1 (TGF‐β1) in the brain. TGF‐β1 has both neuroprotective and neurodegenerative functions, depending on conditions such as duration and the local and temporal pattern of its expression. Previous transgenic approaches did not enable control for these dynamic aspects. To overcome these limitations, we established a transgenic mouse model with inducible neuron‐specific expression of TGF‐β1 based on the tetracycline‐regulated gene expression system. TGF‐β1 expression was restricted to the brain where it was particularly pronounced in the neocortex, hippocampus and striatum. Transgene expression was highly sensitive to the presence of doxycycline and completely silenced within 6 days after doxycycline application. After long‐term expression, perivascular thioflavin‐positive depositions, formed by amyloid fibrils, developed. These depositions persisted even after prolonged silencing of the transgene, indicating an irreversible process. Similarly, strong perivascular apolipoprotein E (ApoE) depositions were found after TGF‐β1 expression and these remained despite TGF‐β1 removal. These in vivo observations suggests that the continuous presence of TGF‐β1 as intitial trigger is not necessary for the persistence and development of chronic lesions. Neuroprotective effects were observed after short‐term expression of TGF‐β1. Death of striatal neurons induced by 3‐nitropropionic acid was markedly reduced after induced TGF‐β1 expression.
Voltage‐gated calcium channels in developing GnRH‐1 neuronal system in the mouse
Authors: Toba Yoko , Pakiam Jennifer G. , Wray Susan
Published: July 2005

Migration of gonadotropin‐releasing hormone‐1 (GnRH‐1) neurons from the nasal placode into the central nervous system occurs in all vertebrates. This study characterizes the expression of L‐ and N‐type voltage‐gated calcium channels (VGCCs) in migrating GnRH‐1 neurons in mice. Class C (L‐type) and class B (N‐type) VGCGs were detected in GnRH‐1 cells and cells in the olfactory and vomeronasal epithelium during prenatal development. This expression pattern was mimicked in a nasal explant model known to retain many characteristics of GnRH‐1 development in vivo. Using this in vitro system, perturbation studies were performed to elucidate the role of VGCCs in GnRH‐1 neuronal development. This report shows that olfactory axon outgrowth and GnRH‐1 neuronal migration are attenuated when nasal explants are grown in calcium‐free media, and that this effect is temporally restricted to an early developmental period. Blockade of either the L‐ or the N‐type channel did not alter GnRH‐1 cell number or overall olfactory axon outgrowth. However, blockade of N‐type channels altered the distribution of GnRH‐1 neurons in the periphery of the nasal explants. In these explants, more GnRH‐1 neurons were located proximal to, and fewer GnRH‐1 neurons distal to, the main tissue mass, suggesting a general decrease in the rate of GnRH‐1 neuronal migration. These results indicate that extracellular calcium is required for initiating GnRH‐1 neuronal migration and that these events are partially dependent on N‐type VGCC signals.
Hypothalamic projections to locus coeruleus neurons in rat brain
Authors: Reyes Beverly A. S. , Valentino Rita J. , Xu Guangping , Van Bockstaele Elisabeth J.
Published: July 2005

Locus coeruleus (LC) neurons respond to autonomic and visceral stimuli and discharge in parallel with peripheral sympathetic nerves. The present study characterized the synaptic organization of hypothalamic afferents with catecholaminergic neurons in the LC using electron microscopy. Peroxidase labeling of axon terminals that were anterogradely labeled from the paraventricular nucleus (PVN) was combined with gold‐silver labeling of tyrosine hydroxylase in the LC. Approximately 19% of the anterogradely labeled axon terminals formed synaptic specializations with tyrosine hydroxylase‐immunoreactive dendrites in the LC. Retrograde transport from the LC combined with immunocytochemical detection of enkephalin and corticotropin‐releasing factor (CRF) suggested that most of the LC‐projecting PVN neurons (30%) were CRF immunoreactive and few (2%) were enkephalin immunoreactive. Finally, dual retrograde tracing from the LC and median eminence revealed that PVN neurons that project to the LC are a population distinct from that projecting to the median eminence. The present data suggest that a population of hypothalamic neurons is poised to directly modulate the activity of LC neurons and may integrate autonomic responses in brain by influencing LC neurons. Moreover, PVN neurons that use CRF as a neurohormone are distinct from those that use CRF as a neuromodulator to impact on the LC.
Functional asymmetry of left and right avian piriform cortex in homing pigeons' navigation
Authors: Gagliardo Anna , Odetti Francesca , Ioalè Paolo , Pecchia Tommaso , Vallortigara Giorgio
Published: July 2005

It has been shown that homing pigeons rely on olfactory cues to navigate over unfamiliar areas and that any kind of olfactory impairment produces a dramatic reduction of navigational performance from unfamiliar sites. The avian piriform cortex is the main projection field of olfactory bulbs and it is supposed to process olfactory information; not surprisingly bilateral lesions to this telencephalic region disrupt homing pigeon navigation. In the present study, we attempted to assess whether the left and right piriform cortex are differentially involved in the use of the olfactory navigational map. Therefore, we released from unfamiliar locations pigeons subjected, when adult, to unilateral ablation of the piriform cortex. After being released, the pigeons lesioned to the right piriform cortex orientated similarly to the intact controls. On the contrary, the left lesioned birds were significantly more scattered than controls, showing a crucial role of the left piriform cortex in processing the olfactory cues needed for determining the direction of displacement. However, both lesioned groups were significantly slower than controls in flying back to the home loft, showing that the integrity of both sides of the piriform cortex is necessary to accomplish the whole homing process.
Diabetes mellitus concomitantly facilitates the induction of long‐term depression and inhibits that of long‐term potentiation in hippocampus
Authors: Artola A. , Kamal A. , Ramakers G. M. J. , Biessels G. J. , Gispen W. H.
Published: July 2005

Memory impairments, which occur regularly across species as a result of ageing, disease (such as diabetes mellitus) and psychological insults, constitute a useful area for investigating the neurobiological basis of learning and memory. Previous studies in rats found that induction of diabetes (with streptozotocin, STZ) impairs long‐term potentiation (LTP) but enhances long‐term depression (LTD) induced by high‐ (HFS) and low‐frequency stimulations (LFS), respectively. Using a pairing protocol under whole‐cell recording conditions to induce synaptic plasticity at Schaffer collateral synapses in hippocampal CA1 slices, we show that LTD and LTP have similar magnitudes in diabetic and age‐matched control rats. But, in diabetic animals, LTD is induced at more polarized and LTP more depolarized membrane potentials (Vms) compared with controls: diabetes produces a 10 mV leftward shift in the threshold for LTD induction and 10 mV rightward shift in the LTD–LTP crossover point of the voltage–response curve for synaptic plasticity. Prior repeated short‐term potentiations or LTP are known to similarly, though reversibly, lower the threshold for LTD induction and raise that for LTP induction. Thus, diabetes‐ and activity‐dependent modulation of synaptic plasticity (referred to as metaplasticity) display similar phenomenologies. In addition, compared with naïve synapses, prior induction of LTP produces a 10 mV leftward shift in Vms for inducing subsequent LTD in control but not in diabetic rats. This could indicate that diabetes acts on synaptic plasticity through mechanisms involved in metaplasticity. Persistent facilitation of LTD and inhibition of LTP may contribute to learning and memory impairments associated with diabetes mellitus.
Selective manipulation of predators using pheromones: responses to frontalin and ipsdienol pheromone components of bark beetles in the Great Lakes region
Authors: Aukema Brian H. , Raffa Kenneth F.
Published: July 2005

Abstract 1 One proposed approach to improving biological control of bark beetles (Coleoptera: Scolytidae; alt. Curculionidae: Scolytinae) is to manipulate predator movement using semiochemicals. However, selective manipulation is impeded by attraction of both predators and pests to bark beetle pheromones.

2 The primary bark beetle affecting pine plantations in Wisconsin, U.S.A., is the pine engraver,Ips pini(Say). Other herbivores includeIps grandicollis(Eichhoff) andDryophthorus americanusBedel (Curculionidae). The predominant predators are the beetlesThanasimus dubius(Cleridae) andPlatysoma cylindrica(Histeridae).

3 We conducted field assays using two enantiomeric ratios of ipsdienol, and frontalin plus α‐pinene. Ipsdienol is the principal pheromone component ofI. pini, and frontalin is produced by a number ofDendroctonusspecies. α‐Pinene is a host monoterpene commonly incorporated into commercial frontalin lures.

4 Thanasimus dubiuswas attracted to frontalin plus α‐pinene, and also to racemic ipsdienol. By contrast,I. piniwas attracted to racemic ipsdienol, but showed no attraction to frontalin plus α‐pinene.Platysoma cylindricawas attracted to 97%‐(–)‐ipsdienol and, to a lesser extent, racemic ipsdienol, but not to frontalin plus α‐pinene.Ips grandicolliswas attracted to frontalin plus α‐pinene but not to ipsdienol.Dryophthorus americanuswas attracted to both ipsdienol and frontalin plus α‐pinene.

5 This ability to selectively attract the predatorT. dubiuswithout attracting the principal bark beetle in the system,I. pini, provides new opportunities for research into augmentative biological control and basic population dynamics. Moreover, the attraction ofT. dubius, but notP. cylindrica, to frontalin plus α‐pinene creates opportunities for selective manipulation of just one predator.

6 Patterns of attraction by predators and bark beetles to these compounds appear to reflect various degrees of geographical and host tree overlap with several pheromone‐producing species.
Forest type affects predation on gypsy moth pupae
Authors: Liebhold A. M. , Raffa K. F. , Diss A. L.
Published: July 2005

Abstract 1 Predation by small mammals has previously been shown to be the largest source of mortality in low‐density gypsy moth,Lymantria dispar(L.), populations in established populations in north‐eastern North America. Fluctuations in predation levels are critical in determining changes in population densities.

2 We compared small mammal communities and levels of predation on gypsy moth pupae among five different oak‐dominated forest types along this insect's western expanding population front in Wisconsin. Comparisons of predator impact can provide critical information for predicting variation in susceptibility among forest types.

3 The results indicated that small mammals caused more mortality than did invertebrates.

4 Both abundance ofPeromyscussp. predators and predation levels were lower in urban and xeric forest types than in mesic sites.

5 These results suggest that, because predation pressures will probably be greater in the mesic sites, gypsy moths may be less likely to develop outbreaks in these habitats, and that defoliation will probably be more frequent in urban and xeric oak‐dominated sites.
Primary attraction and kairomonal host discrimination in three species of Dendroctonus (Coleoptera: Scolytidae)
Authors: Pureswaran Deepa S. , Borden John H.
Published: July 2005

Abstract  1 Synthetic blends of bole and foliage volatiles of four sympatric species of conifers were released from pheromone‐baited multiple‐funnel traps to determine if three species of tree‐killing bark beetles (Coleoptera: Scolytidae): (i) exhibited primary attraction to volatiles of their hosts and (ii) discriminated among volatiles of four sympatric species of host and nonhost conifers.

2 Bole and foliage volatiles from Douglas‐fir, Pseudotsuga menziesii (Mirb.) Franco, increased the attraction of coastal and interior Douglas‐fir beetles, Dendroctonus pseudotsugae Hopkins, to pheromone‐baited traps. Primary attraction to bole volatiles was observed in interior D. pseudotsugae. Beetles were significantly less attracted to the pheromone bait when it was combined with volatiles of lodgepole pine, Pinus contorta var. latifolia Engelm. or interior fir, Abies lasiocarpa × bifolia.

3 The monoterpene myrcene synergized attraction of mountain pine beetles, Dendroctonus ponderosae Hopkins, to their aggregation pheromones, but there was no evidence of primary attraction to host volatiles or discrimination among volatiles from the four conifers.

4 There was significant primary attraction of the spruce beetle, Dendroctonus rufipennis Kirby, to bole and foliage volatiles of interior spruce, Picea engelmannii × glauca, but beetles did not discriminate among volatiles of four sympatric conifers when they were combined with pheromone baits.

5 Our results indicate that host volatiles act as kairomones to aid pioneer Douglas‐fir beetles and spruce beetles in host location by primary attraction, and that their role as synergists to aggregation pheromones is significant. For the mountain pine beetle, we conclude that random landing and close range acceptance or rejection of potential hosts would occur in the absence of aggregation pheromones emanating from a tree under attack.
Resistance of fast‐ and slow‐growing subalpine fir to pheromone‐induced attack by western balsam bark beetle (Coleoptera: Scolytinae)
Authors: Bleiker Katherine P. , Staffan Lindgren B. , Maclauchlan Lorraine E.
Published: July 2005

Abstract  1 We investigated the resistance of fast‐ and slow‐growing subalpine fir to pheromone‐induced attack by western balsam bark beetle at two sites in the interior of British Columbia, Canada.

2 Attack success by the beetle and subsequent tree mortality were higher in slow‐growing trees than in fast‐growing trees.

3 Fast‐growing trees were more likely to produce secondary resin, and in greater quantities, than slow‐growing trees after attack.

4 Host vigour (indicated by recent radial growth) was positively related to the induced defense response and resistance of subalpine fir to bark beetle attack. These results are discussed in the context of plant defense and plant–herbivore interaction hypotheses.

5 Given the preference of western balsam bark beetle for weakened trees, as well as the reduced defenses and increased mortality rates in less vigorous trees, effective management tactics for this beetle may include strategies that increase the growth and vigour of its subalpine fir host.
Dual colonization of Eucalyptus urophylla S.T. Blake by arbuscular and ectomycorrhizal fungi affects levels of insect herbivore attack
Authors: Gange Alan C. , Gane Dominic R. J. , Chen Yinglong , Gong Mingqin
Published: July 2005

Abstract  1 Eucalypts are an important part of plantation forestry in Asia but, in south China, productivity is very low. This is due to infertile soils and lack of indigenous symbiotic mycorrhizal fungi. The genus Eucalyptus is unusual because it forms both arbuscular (AM) and ectomycorrhizal (ECM) associations.

2 Eucalyptus urophylla saplings were grown with and without AM (Glomus caledonium) and ECM (Laccaria laccata) fungi in a factorial design. Two experiments were performed: one to simulate nursery conditions and the other to simulate the early stages of plantation establishment. Plant growth was measured over 18 weeks and levels of insect attack were recorded.

3 The AM fungus reduced tree growth in the early stages, but the effect appeared to be transient. No effects of ECM were detected on tree growth, but the ectomycorrhiza reduced colonization by the arbuscular mycorrhiza. AM fungi appear to be rapid invaders of the root system, gradually being replaced by ECM.

4 Both fungal types affected levels of damage by insect herbivores. Most importantly, herbivory by the pest insects Anomala cupripes (Coleoptera) and Strepsicrates spp. (Lepidoptera) was decreased by ECM.

5 It is suggested that mycorrhizal effects on eucalypt insects may be determined by carbon allocation within the plant. Future studies of eucalypt mycorrhizas need to take into account the effects of the fungi on foliar‐feeding insects and also the effects of insect herbivory on mycorrhizal establishment.
How to facilitate parents and their premature infant for the transition home
Authors: Broedsgaard A. , Wagner L.
Published: July 2005

Background:  An intervention programme was carried through in a neonatal intensive care unit at the Copenhagen University Hospital in Denmark in 1998/99. It comprised: (1) educational programmes during hospitalization for parents with premature infants; (2) visit and orientation about the neonatal intensive care unit by the family's health visitor; a multidisciplinary and cross‐sector discharge conference; and (3) publication of relevant booklets for parents and health care providers.

Aim:  To present the parents’ experiences from this intervention, concerning support and coordination following delivery of a premature infant.

Method:  A non‐experimental design and descriptive study. The qualitative methods used were semi‐structured questionnaires and focus group interviews.

Findings:  The parents found that most of the intervention initiatives contributed to increased support and met their needs, including contributing to their confidence in caring for their premature infant and its well‐being following discharge. The study contributed to meaningful knowledge about the consequences for parents and premature infants when mother and infant are separated in the beginning of life, mindful of the process of mother–infant bonding.

Implications:  Major actions from the intervention programme now form permanent functions in the neonatal intensive care unit as well as in the primary health care sector. The study also confirmed the benefit of the role of the nurse‐coordinator.
Residents’ rights and nurses’ ethics in the Australian nursing home
Authors: Tuckett A. G.
Published: July 2005

Background: This article is derived from a more extensive review of literature for a qualitative study that explored the meaning of truth‐telling within the care provider – aged resident dyad in high‐level (nursing home) aged care.

Aim: This paper describes through the literature, work practices and the culture of the nursing home as promoting instrumental care, therefore prioritizing doing‐for over being‐with. The nursing home, starved of time and staff, silences and isolates the aged care resident in an environment that is, arguably, rarely homelike.

Conclusion: The appraisal of the nursing home offered here means that a number of residents’ rights are at risk and care providers (notably registered nurses and the personal care assistants) risk contravening theCode of Ethics for Nurses in Australia.
Viability of probiotic micro‐organisms during storage, postacidification and sensory analysis of fat‐free yogurts with added whey protein concentrate
Authors: ANTUNES ADRIANE E C , CAZETTO TALITA F , BOLINI HELENA M A
Published: July 2005

The aim of this research was to evaluate the effect of the addition of whey protein concentrate (WPC) on the viability of Lactobacillus acidophilus and Bifidobacterium longum and on postacidification throughout the shelf life of fat‐free yogurts, and also to analyse the sensory characteristics of the products. Postacidification was not significantly changed by the addition of WPC, but was decreased by Lactobacillus bulgaricus inoculation. WPC did not influence the viability of the lactic acid bacteria (L. bulgaricus and Streptococcus thermophilus), but it improved the growth and survival of the micro‐organisms L. acidophilus and B. longum, especially the former. The panellists did not identify significant differences (P < 0.05) of the yogurts due to the addition of WPC.
Comparison of the characteristics of teleme cheese made from ewe's, goat's and cow's milk or a mixture of ewe's and goat's milk
Authors: MALLATOU H , PAPPA E C
Published: July 2005

Teleme cheeses were manufactured from ewe's, goat's and cow's milk and mixture of ewe's and goat's milk. Physicochemical and biochemical analyses of the cheeses at various stages of ripening and storage were performed. Cheeses made from goat's milk had lower moisture content than those made from other milks. No significant differences in the mean values of protein, salt and water activity (a

w

) of the different cheeses at all ages studied were found. Cheeses from goat's and cow's milk had higher contents of fat and fat in dry matter (FDM) compared to that of cheeses from ewe's milk and mixed milk. Significant differences were observed in the yield and yield on 56% moisture: cheeses from ewe's milk gave the highest yield and cheese from cow's milk the lowest. Significant differences were found in the ashes content of the different cheeses at all ages. No differences in cholesterol and cholesterol/fat contents of the four types of cheeses were found. Main and trace elements showed variability among the four cheeses.
Manufacturing, properties and shelf life of labneh: a review
Authors: NSABIMANA CONSOLATE , JIANG BO , KOSSAH RIMA
Published: July 2005

Labneh is a concentrated yogurt widely produced and consumed in the Middle Eastern countries and Balkans.

This review focuses attention on the different manufacturing methods of labneh and its quality in terms of microbiology, rheology, sensory and nutrition. The shelf life of this healthy milk‐derived product is also discussed in this review.