bluuebunny/crossref_metadata_2025_split huggingface dataset:
Calcium, the Universe and Everything
Authors: SANDERSON J 
Published: October 2007

AbstractCalcium plays a pivotal role in lens physiology and pathophysiology. I will review research from the Norwich Eye Lab, which has been fundamental in establishing calcium and its function in the lens.Human cortical cataract is associated with a loss of ionic homeostasis, with calcium overload a hallmark of this disease. Free calcium has also been found to increase in non‐cataractous human lenses as a result of aging, suggesting that it may be an early event in cataractogenesis. Lens organ culture experiments, using bovine and human lenses, have shown that calcium overload is indeed fundamental in loss of lens transparency. Raised intracellular calcium initiated proteolytic events both in the soluble (crystallin) fraction and the cytoskeletal fraction, supporting a role for the calcium‐activated protease calpain in the opacification process. In order to understand mechanisms of calcium overload, it is also important to understand the mechanisms of normal calcium homeostasis in the lens. This has been extensively studied, mainly in lens epithelial cells, with a particular emphasis on the role of the endoplasmic reticulum calcium store. Investigation of calcium signaling has, in addition to this, shown the lens to have a remarkable and diverse pharmacology, with functional expression of a plethora of receptors which signal via calcium including muscarinic receptors, purinoceptors and EGF receptors. Recent work in the lab has also extended this interest in calcium in the lens to other ocular cells types, where calcium signaling could have a role to play in other eye diseases such as retinal detachment and glaucoma.Investigation of calcium in the lens has demonstrated a central role in the pathophysiology of cortical cataract. By understanding the molecular mechanisms underlying cataractogenesis we move closer to the development of pharmacological strategies for the treatment of this disease.
Physiological effects of vitrectomy and retinal laser treatment explain their clinical effects: Vitrectomy and laser treatment both affect retinal oxygenation and benefit ischemic retinopathies
Authors: STEFANSSON E 
Published: October 2007

AbstractClinical studies have established that retinal laser photocoagulation on one hand and vitrectomy on the other have a positive clinical effect on the development of diabetic retinopathy and other ischemic retinopathies. Both reduce retinal neovascularization and macular edema. The clinical effect of laser and vitrectomy is related to the physiological effect of these treatment modalities. Both improve retinal oxygenation, but through different mechanisms. Laser treatment destroys some of the photoreceptors, reduces the oxygen consumption of the outer retina and allows oxygen to diffuse from the choroid to the inner retina.In vitreous surgery the viscous vitreous gel is replaced by low viscosity water. According to the Stokes‐Einstein equation viscosity is inversely related to the diffusion coefficient. Diffusion (and convection) of any substance is many times higher in water than vitreous gel, and this includes oxygen, growth factors and drugs. In the vitrectomized eye, oxygen diffuses more easily from well perfused to hypoxic areas of the retina. At the same time growth factors are cleared from the retina more rapidly than before and may indeed be transported to the anterior segment and produce iris neovascularization.Laser and vitrectomy reduce retinal hypoxia and thereby reduce the production of hypoxia induced growth factors such as VEGF. Vitrectomy also clears VEGF away from the retina at a more rapid rate than when the vitreous gel is in place. VEGF and other growth factors influence both neovascularization and capillary permeability, and the latter influences the osmotic balance between blood and tissue and the osmotic arm of Starling´s law. In addition, improved oxygenation reduces the hypoxia‐induced vasodilatation and this decreases capillary blood pressure and reduces edema formation according to the hydrostatic arm of Starling´s law.By understanding the physiological effects of laser and vitrectomy, we can understand the mechanism of the clinical effect. Classical laws of physiology and physics help complete the picture and give us an understanding of the nature of these treatment modalities and how they may be combined with other agents.For details and references please see Stefánsson E: Survey of Ophthalmology 2006.
UK experience and evolving strategies to improve results I ‐ clinical results
Authors: PERERA S , OKERA S , TANDON R , HEROLD J , HULL C , THORP S , LIU C 
Published: October 2007

Abstract Purpose: To report the long term results of osteo‐odonto‐keratoprosthesis (OOKP) surgery in the visual rehabilitation of patients with corneal blindness from end stage inflammatory ocular surface disease. Methods: A non‐comparative retrospective interventional case series.36 consecutive patients treated at the National OOKP referral centre in Brighton, United Kingdom, between November 1996 and March 2006.Osteo‐odonto‐keratoprosthesis surgery performed in line with the Rome‐Vienna protocol.Anatomical retention, visual acuity, retention of best attained visual acuity, visual field, complications resulting in anatomical or visual failure, de novo glaucoma rate. Results: A total of 36 patients, with age ranging from 19 to 87 years (mean 51 ± 19 years), were included in the analysis. The main preoperative diagnoses were Stevens Johnson syndrome (n=16, or 44%), severe thermal or chemical burns (n=6, or 17%), and mucous membrane pemphigoid (n=5, or 14%). The remainder of the cases comprised miscellaneous causes of dry eye (n=9, or 25%), which included one each of graft versus host disease, ectodermal dysplasia, ionising radiation damage, cicatrising conjunctivitis from topical medication, trachoma, congenital trigeminal nerve hypoplasia, linear IgA disease, Sjogren’s syndrome, and nutritional deficiency. Follow‐up ranged from 6 months to nine years (mean 3.86 ± 2.45 years). Anatomical retention during the entirety of the follow‐up period was seen in 72% of patients. The main factor resulting in anatomical failure was resorption of the OOKP lamina, which occurred in seven cases (or 19%). Predicted resorption in three cases resulted in successful planned exchange of the lamina, but two cases underwent emergency removal of the OOKP, and two cases developed endophthalmitis. HLA matched allografts suffered a higher rate of laminar resorption. Out of the entire cohort, thirty patients (or 83%) had some improvement in vision, twenty eight (or 78%) achieved vision of 6/60 or better, and nineteen (or 53%) achieved 6/12 or better. The best‐achieved vision was retained throughout the follow‐up period in 61% of cases. Survival analysis suggested that the probability of retaining vision >6/60 five years after surgery was 53%±10%. Vision threatening complications occurred in 9 cases (or 25%), and included endophthalmitis, retinal detachment, and glaucoma. De novo glaucoma occurred in six patients (or 24%) but was seen overall in seventeen patients (or 47%), ten of whom required surgical treatment. Conclusions: OOKP surgery can restore useful and lasting vision in patients suffering from end stage ocular surface disease, for whom conventional corneal surgery is not possible. The main problems seen in this study were laminar resorption, particularly in allografts, and glaucoma.
Advances in the Type I Boston Keratoprosthesis
Authors: COLBY K , DOHLMANN C 
Published: October 2007

Abstract Purpose: To give an update on the Type I Boston keratoprosthesis (KPro). Methods: We reviewed our recent experiences with the Type I Boston KPro with attention to design modifications, use in pediatric patients, post‐operative care and management of complications. Results: The use of the Type I Boston KPro has increased dramatically since 2003, when only 57 of these devices were implanted. In 2006, more than 450 Type I Boston KPro’s were implanted worldwide. Recent modifications include a threadless front plate stem designed to reduce trauma to and maintain the health of the carrier corneal graft. The Type I Boston KPro appears to be a viable alternative to PK in children with corneal opacities and may simplify amblyopia management. Post‐operative care following Boston KPro placement remains critical, with availability of preserved vancomycin reducing the risk of endophthalmitis. Management of complications including cataract formation and retinal detachment following Boston KPro will be discussed. Conclusions: The Type I Boston keratoprosthesis has shown continued acceptance among corneal surgeons throughout the world. Ongoing work at our institution aims to improve the utility of this device while minimizing complications from its use.
Boston KPro collaborative study results
Authors: BELIN MW 
Published: October 2007

Abstract Purpose: To report the indications, practices, complications, and outcomes from the first multi‐center study on the Boston Type 1 Keratoprosthesis. Methods: We analyzed 218 Boston Type 1 Keratoprosthesis surgical procedures, from 20 surgical sites, implanted from January 2003 through August 2007 in 210 eyes of 205 patients. Forms reporting seventy pre‐, intra‐, and post‐operative parameters were collected and analyzed at a central data collection site (Cornea Consultants of Albany, PLLC, Albany Medical College, Albany, NY). The main outcome measures were; Visual acuity and keratoprosthesis survival. Results: Common preoperative diagnoses were graft rejection in 103 eyes (47%) (average prior grafts: 2.24), chemical injury (26 eyes, 12%), bullous keratopathy (34 eyes, 16%), and herpes simplex virus keratitis (12 eyes, 6%). Additionally, 100 eyes (46%) had preoperative glaucoma. Preoperative best‐corrected visual acuity ranged from 20/100 to light perception, and was less than 20/200 in 94% of eyes. At an average follow‐up of 9.4 months, postoperative vision improved to ≥ 20/200 in 63%. Among eyes at least 1 year postoperative (104 eyes), vision was ≥ 20/200 in 58% of eyes and ≥ 20/40 in 17%. At an average follow‐up of 9.4 months, graft retention was 96%. Severe visual loss or failure to improve from keratoprosthesis was usually secondary to comorbidities such as advanced glaucoma, macular degeneration, or retinal detachment. Conclusions: The Boston Type 1 Keratoprosthesis seems to be a viable option after multiple failed corneal grafts or in some situations with a poor prognosis for primary penetrating keratoplasty.
Infection control in KPros
Authors: NOURI M 
Published: October 2007

Abstract Purpose: To study Boston KPro‐related infections. Methods: Retrospective review of case notes. Results: Since 1990, 350 patients have undergone Boston Keratoprosthesis surgery. An analysis has been made of those affected by bacterial or fungal infections. The results will be presented. Conclusions: Strategies to prevent and treat Boston KPro‐related ocular infections will be presented.
ACTA lecture: The retinal pigment epithelium, friend or foe?
Authors: LA COUR M 
Published: October 2007

Abstract Purpose: To review the physiology and pathophysiology of the retinal pigment epithelium, RPE, with focus on some of the work of myself and my wonderful collaborators and students during the last 20 years. Methods: In vitro studies of RPE preparations from frogs and of cultured human and porcine RPE cells. In vivo studies of experimental surgery in pigs using histopathology, immunohistochemistry and functional testing by multifocal electoretinograhpy. Results: There are active fluid transport mechanisms in the RPE, which are capable of transporting water aganist an osmotic gradient. This has important bearings on the fundus appearance in states of macular oedema.RPE cell physiology is dependent on the surface on which they grow, and the maturity of the cells. Older RPE cells are more stress resistant than younger RPE cells. This has important bearings on studies where cultured RPE cells are used to assess toxicity of substances used in the clinic.In vivo RPE cells are non‐dividing under normal circumstances. Posterior injury to the epithelium induces proliferation of the peripheral, but not the posterior RPE. This indicates that a g zone of putative RPE stem cells might exist in the peripheral retina.The functional consequences of experimental posterior RPE injury can be assessed by multifocal electroretinography Conclusions: The RPE plays an important role in the normal physiology og the outer retina, as well as in the pathogenesis of retinal diseases. The development of animal models of RPE injury increase our understanding of the role of RPE in health and disease.
Intraperitoneal application of rituximab in refractory mantle cell lymphoma with massive ascites resulting in local and systemic response
Authors: Crysandt Martina , Neumann Britta , Das Marco , Engelbertz Vera , Bendel Michael , Galm Oliver , Osieka Rainhardt , Jost Edgar 
Published: September 2007

AbstractIn the past decade, rituximab in combination with polychemotherapy has become the standard approach in most patients with advanced CD20‐positive B‐cell lymphoma. In mantle cell lymphoma (MCL), follicular lymphoma and diffuse large B‐cell lymphoma, rituximab has been used as monotherapy and in combination with various chemotherapy regimens in different treatment situations. Routinely, rituximab is given intravenously, but other routes of administration have also been described. Here, we report a 64‐yr‐old woman who was previously treated with three different chemotherapy regimens for stage IV MCL. No sustained clinical and radiological response could be achieved. The patient’s general status declined and she developed massive ascites as the dominant clinical problem. Local, intraperitoneal administration of rituximab was initiated as an experimental treatment approach. After 11 doses of rituximab, the general status of the patient improved significantly, ascites resolved completely and computed tomography (CT) scans demonstrated a partial remission of intra‐abdominal lymph nodes and splenomegaly. Furthermore, we observed a regression of mediastinal lymph nodes, pleural effusion and centrocytes in peripheral blood as well as improvement of anaemia. The response to the experimental treatment has maintained for more than 6 months. In summary, we observed a sustained local and systemic response to intraperitoneal administration of rituximab in a patient with heavily pretreated advanced MCL.
Scope of practice, referral patterns and lesion occurrence of an oral medicine service in Australia
Authors: Farah CS , Simanovic B , Savage NW 
Published: September 2007

Aim:  The purpose of this study was to examine the scope of practice, lesion occurrence and utilisation of referral‐based hospital and private practice oral medicine and oral pathology (OMP) services in Australia.Materials and methods:  Clinical records of patients referred to a hospital (n=500) and private (nbequals;1104) OMP clinic were audited. For each patient, the following parameters were recorded: age, gender, source of referral, reason for referral, site of lesion/condition if applicable, medical and drug history, diagnostic services utilised, clinical and histopathological diagnoses rendered, medications prescribed and further treatment required.Results:  A majority of the referrals were generated by general dental practitioners. The most commonly seen problems were epithelial hyperplasia/hyperkeratosis, oral candidosis, oral lichen planus, xerostomia, recurrent aphthous ulcers and burning mouth syndrome. OMP specialists requested diagnostic imaging for 13% of hospital and 9.42% of private patients, diagnostic biopsies were required for 18.4% of hospital and 19.3% of private patients, blood tests were ordered for 14.4% of hospital and 12.13% of private patients, while medications were prescribed for approximately 36% of hospital and 51% of private patients.Conclusions:  This study is the first to detail the scope of practice, lesion occurrence and utilisation of services offered by OMP specialists in Australia. The demand for OMP services is strong.
In Vitro Evaluation of the Activities of Telavancin, Cefazolin, and Vancomycin against Methicillin-Susceptible and Methicillin-Resistant
Staphylococcus aureus
in Peritoneal Dialysate
Authors: Clouse Frances L. , Hovde Laurie B. , Rotschafer John C. 
Published: October 2007

ABSTRACT

This study compared the ability of telavancin to the ability of cefazolin and vancomycin to eliminate staphylococci from peritoneal dialysis fluid by using a static in vitro model to simulate the conditions of peritoneal dialysis. The results showed that telavancin exhibited statistically significantly better kill (
P
< 0.05) against both methicillin-susceptible and methicillin-resistant
Staphylococcus aureus
.
Frequency of Development and Associated Physiological Cost of Azithromycin Resistance in
Chlamydia psittaci
6BC and
C. trachomatis
L2
Authors: Binet Rachel , Maurelli Anthony T. 
Published: October 2007

ABSTRACT

Azithromycin is a major drug used in the treatment and prophylaxis of chlamydial infections. Spontaneous azithromycin-resistant mutants of
Chlamydia psittaci
6BC were isolated in vitro in the plaque assay at a frequency of about 10
−8
. Isogenic clonal variants with A
2058
C, A
2059
G, or A
2059
C mutations in the unique 23S rRNA gene (
Escherichia coli
numbering system) displayed MICs for multiple macrolides (i.e., azithromycin, erythromycin, josamycin, and spiramycin) at least 100 times higher than those of the parent strain and were also more resistant to the lincosamide clindamycin.
Chlamydia trachomatis
L2 variants with a Gln-to-Lys substitution in ribosomal protein L4 at position 66 (
E. coli
numbering system), conferring an eightfold decrease in azithromycin and erythromycin sensitivities and a fourfold decrease in josamycin and spiramycin sensitivities, were isolated following serial passage in subinhibitory concentrations of azithromycin. Each mutation was stably maintained in the absence of selection but severely affected chlamydial infectivity, as determined by monitoring the development of each isolate over 46 h in the absence of selection, in pure culture or in 1:1 competition with the isogenic parent. Data in this study support the hypothesis that the mechanisms which confer high-level macrolide resistance in chlamydiae carry a prohibitive physiological cost and may thus limit the emergence of highly resistant clones of these important pathogens in vivo.
Diversity of
ndo
Genes in Mangrove Sediments Exposed to Different Sources of Polycyclic Aromatic Hydrocarbon Pollution
Authors: Gomes Newton C. Marcial , Borges Ludmila R. , Paranhos Rodolfo , Pinto Fernando N. , Krögerrecklenfort Ellen , Mendonça-Hagler Leda C. S. , Smalla Kornelia 
Published: September 2007

ABSTRACT

Polycyclic aromatic hydrocarbon (PAH) pollutants originating from oil spills and wood and fuel combustion are pollutants which are among the major threats to mangrove ecosystems. In this study, the composition and relative abundance in the sediment bacterial communities of naphthalene dioxygenase (
ndo
) genes which are important for bacterial adaptation to environmental PAH contamination were investigated. Three urban mangrove sites which had characteristic compositions and levels of PAH compounds in the sediments were selected. The diversity and relative abundance of
ndo
genes in total community DNA were assessed by a newly developed
ndo
denaturing gradient gel electrophoresis (DGGE) approach and by PCR amplification with primers targeting
ndo
genes with subsequent Southern blot hybridization analyses. Bacterial populations inhabiting sediments of urban mangroves under the impact of different sources of PAH contamination harbor distinct
ndo
genotypes. Sequencing of cloned
ndo
amplicons comigrating with dominant DGGE bands revealed new
ndo
genotypes. PCR-Southern blot analysis and
ndo
DGGE showed that the frequently studied
nah
and
phn
genotypes were not detected as dominant
ndo
types in the mangrove sediments. However,
ndo
genotypes related to
nagAc
-like genes were detected, but only in oil-contaminated mangrove sediments. The long-term impact of PAH contamination, together with the specific environmental conditions at each site, may have affected the abundance and diversity of
ndo
genes in sediments of urban mangroves.
Sequential Aldol Condensation Catalyzed by Hyperthermophilic 2-Deoxy-
d
-Ribose-5-Phosphate Aldolase
Authors: Sakuraba Haruhiko , Yoneda Kazunari , Yoshihara Kumiko , Satoh Kyoko , Kawakami Ryushi , Uto Yoshihiro , Tsuge Hideaki , Takahashi Katsuyuki , Hori Hitoshi , Ohshima Toshihisa 
Published: September 2007

ABSTRACT

Genes encoding 2-deoxy-
d
-ribose-5-phosphate aldolase (DERA) homologues from two hyperthermophiles, the archaeon
Pyrobaculum aerophilum
and the bacterium
Thermotoga maritima
, were expressed individually in
Escherichia coli
, after which the structures and activities of the enzymes produced were characterized and compared with those of
E. coli
DERA. To our surprise, the two hyperthermophilic DERAs showed much greater catalysis of sequential aldol condensation using three acetaldehydes as substrates than the
E. coli
enzyme, even at a low temperature (25°C), although both enzymes showed much less 2-deoxy-
d
-ribose-5-phosphate synthetic activity. Both the enzymes were highly resistant to high concentrations of acetaldehyde and retained about 50% of their initial activities after a 20-h exposure to 300 mM acetaldehyde at 25°C, whereas the
E. coli
DERA was almost completely inactivated after a 2-h exposure under the same conditions. The structure of the
P. aerophilum
DERA was determined by X-ray crystallography to a resolution of 2.0 Å. The main chain coordinate of the
P. aerophilum
enzyme monomer was quite similar to those of the
T. maritima
and
E. coli
enzymes, whose crystal structures have already been solved. However, the quaternary structure of the hyperthermophilic enzymes was totally different from that of the
E. coli
DERA. The areas of the subunit-subunit interface in the dimer of the hyperthermophilic enzymes are much larger than that of the
E. coli
enzyme. This promotes the formation of the unique dimeric structure and strengthens the hydrophobic intersubunit interactions. These structural features are considered responsible for the extremely high stability of the hyperthermophilic DERAs.
Evaluation of Postharvest-Processed Oysters by Using PCR-Based Most-Probable-Number Enumeration of
Vibrio vulnificus
Bacteria
Authors: Wright Anita C. , Garrido Victor , Debuex Georgia , Farrell-Evans Melissa , Mudbidri Archana A. , Otwell W. Steven 
Published: September 2007

ABSTRACT

Postharvest processing (PHP) is used to reduce levels of
Vibrio vulnificus
in oysters, but process validation is labor-intensive and expensive. Therefore, quantitative PCR was evaluated as a rapid confirmation method for most-probable-number enumeration (QPCR-MPN) of
V. vulnificus
bacteria in PHP oysters. QPCR-MPN showed excellent correlation (
R
2
= 0.97) with standard MPN and increased assay sensitivity and efficiency.