bluuebunny/crossref_metadata_2025_split huggingface dataset:
Age-related macular degeneration and recent developments: new hope for old eyes?
Authors: Morris Brid , Imrie Fraser , Armbrecht Ana-Maria , Dhillon Baljean 
Published: May 2007

Abstract
Age-related macular degeneration (AMD) is the commonest cause of blindness in the population over 60 years of age and accounts for over 50% of those registered blind in the UK. The incidence is increasing and as older generations live longer a growing number of patients will be affected in the future. Affected patients lose central vision, important in all aspects of everyday life. This review outlines risk factors for AMD, clinical features, treatment and management strategies for patients, families and physicians caring for those with AMD. Recent trials are included along with practical clinical advice. While there is no curative treatment at present, intervention can reduce the risk of developing AMD and limit disease progression if it occurs. These modalities are discussed here. As new discoveries in the field of genetics and novel therapies emerge, a brighter future seems certain for the ageing population.
Effects of comorbidity and hospital care on 6-month mortality in patients with elevated cardiac troponin T
Authors: Wong P , Ramsewak A , Murray S , Robinson A , Robinson D , Rodrigues E 
Published: May 2007

Abstract

Objective
To examine the effects of comorbidity and hospital care on mortality in patients with elevated cardiac troponin T.

Design
Observational study.

Setting
A large university hospital with on-site diagnostic cardiac catheter laboratory.

Patients
All hospitalised patients with elevated cardiac troponin T level (⩾0.01 μg/l) over an 8-week period.

Main outcome measures
6-month all-cause mortality.

Results
Among 313 patients with elevated cardiac troponin T, 195 had acute coronary syndrome and 118 had other conditions. Multivariate analysis showed that among patients with acute coronary syndrome, increasing comorbidity score (odds ratio (OR) 1.23 per point increase, 95% confidence interval (CI) 1.00 to 1.51; p = 0.048), age (OR 1.08 per year, 95% CI 1.04 to 1.13; p&lt;0.001), raised troponin T level (OR 2.22 per 10-fold increase, 95% CI 1.27 to 3.89; p = 0.005), and ST depression (OR 3.12, 95% CI 1.38 to 7.03; p = 0.006) were independent adverse predictors, while cardiologist care (OR 0.22, 95% CI 0.09 to 0.51; p&lt;0.001) was associated with a better survival. Increasing troponin T level (OR 3.33 per 10-fold increase, 95% CI 1.24 to 8.91; p = 0.017) was found to predict a worse prognosis among patients without acute coronary syndrome, and cardiologist care did not affect outcome in this group. Among hospital survivors with acute coronary syndrome, increasing comorbidity score, age and a lack of cardiologist care were independently associated with lesser use of effective medications.

Conclusions
Comorbidity was associated with a higher 6-month mortality in patients having acute coronary syndrome, and lesser use of effective medicines among hospital survivors. Cardiologist care was associated with better 6-month survival in patients with acute coronary syndrome, but not in those without acute coronary syndrome.
Maimonides: an early but accurate view on the treatment of haemorrhoids
Authors: Magrill Dan , Sekaran Prabhu 
Published: May 2007

Abstract
Moses Maimonides was not only one of the most influential religious figures of the middle ages, but also a pioneer in a wide variety of medical practices. A brief history of his life, and what is known about his medical education, is given here. His paper on haemorrhoids is summarised, as well as a review of the current understanding of the pathogenesis, prevention and treatment of this common condition. The comparison of Maimonides' writings to modern understanding of not only the prevention and treatment of haemorrhoids, but also his approach to the patient as a whole in terms of pre- and postoperative care, demonstrate how ahead of his time this great philosopher was.
Left ventricle diastolic function in the patients after coronary arteries bypass graft combined with left ventricle aneurismectomy according to tissue doppler imaging: one year follow-up
Authors: Dolzhenko Maryna N , Rudenko S A , Potashev S V , Simagina T V , Nosenko N N , Kravchenko T G 
Published: May 2007

Abstract

Aim
To evaluate left ventricle (LV) diastolic function dynamics in patients after acute myocardial infarction (AMI) after combined operation of coronary artery bypass graft with LV aneurismectomy (CABG + AE) according to the results of tissue Doppler imaging (TDI).

Methods
Forty patients after AMI underwent Doppler echocardiography (EchoCG) with TDI and M-mode colour-flow imaging before and in 3 and 12 months after CABG + AE. Mitral annulus (MA) TDI with velocity indices was performed in 4 segments of LV.

Results
Conventional transmitral diastolic Doppler indices before and after CABG + AE remained unchanged. TDI showed significant improvement of LV systolic (systolic movement velocity S: 6.1±0.8, 7.4±1.2 and 6.9±1.3 cm/sec. before and in 3 and 12 months after the operation, respectively, p&lt;0.01) and diastolic function after the operation (MA early diastolic movement velocity (e’): 7.3 ± 2.1, 8.4 ± 1.5 and 8.9 ± 1.8 cm/s.; ratio of transmitral early-flow velocity (E) to MA early-diastolic movement velocity (E/e’): 18.4 ± 2.2, 12.3 ± 1.8 and 11.5 ± 2.3; ratio of E diastolic flow propagation velocity (Vp) 3.1 ± 0.45, 2.2 ± 0.38 and 1.8 ± 0.16 before and in 3 and 12 months after the operation, respectively, p&lt;0.01).

Conclusions
Results of the study demonstrate significant improvement of LV diastolic function in the patient after CABG + AE according to TDI, regardless of transmitral flow pattern. TDI is more sensitive and preload independent method of LV myocardial function evaluation.
Synergistic effect of triptolide combined with 5-fluorouracil on colon carcinoma
Authors: Tang Xiao-yan , Zhu You-qing , Tao Wen-hui , Wei Bai , Lin Xiao-ling 
Published: May 2007

AbstractAimTo investigate the inhibitive effects of triptolide (TPL) combined with 5-fluorouracil (5-FU) on colon carcinoma HT-29 cells in vitro and in vivo and their side effects.MethodsHT-29 cells were cultured with RPMI 1640 medium. The single or combined effects of TPL and 5-FU on HT-29 cells were examined by MTT assay, flow cytometry. The combined effects were evaluated by the median-effect principle. The model of tumour xenografts was established in nude mice. TPL 0.25 mg/kg/day and 5-FU 12 mg/kg/day, either in combination or on their own, were injected into mice and the inhibitive effects and side effects were observed.ResultsTPL and 5-FU either combined or alone inhibited significantly the proliferation of HT-29 cells and induced obvious apoptosis. Mean (SD) growth inhibition rate reached 94.92 (2.76)% and the apoptic rate at 48 h reached 41.71 (1.38)%. The combined effects were synergistic (CI&lt;1) at lower concentrations. TPL or 5-FU alone inhibited significantly the growth of tumour xenografts and the inhibition rates were 78.53% and 84.16%; the drugs combined had more significant effect, the tumour inhibition rate reaching 96.78%. During the course of chemotherapy, no obvious side effect was observed.ConclusionThe combined effects of TPL and 5-FU on the growth of colon carcinoma in vitro and in vivo were superior to the effects when the agents were used individually. TPL combined with 5-FU had synergistic effects at lower concentrations and promoted apoptosis, but did not increase the side effects of chemotherapy.
Influence of curcumin, capsaicin, and piperine on the rat liver drug-metabolizing enzyme system in vivo and in vitro
Authors: Suresh D. , Srinivasan K. 
Published: May 2007

The effect of dietary supplementation of spice-active principles, curcumin (0.2%), capsaicin (0.015%), and piperine (0.02%) on the activities of the liver drug-metabolizing enzyme system was examined. All the 3 dietary spice principles significantly stimulated the activity of aryl hydroxylase. A synergistic action of dietary curcumin and capsaicin with respect to stimulating the activity of aryl hydroxylase was also evidenced when fed in combination. The activity of N-demethylase essentially remained unaffected by dietary curcumin, capsaicin, or their combination, but was significantly lowered as a result of piperine feeding. Uridine dinucleotide phosphate (UDP)-glucuronyl transferase activity was decreased by dietary piperine and the combination of curcumin and capsaicin. NADPH-cytochrome c reductase activity was significantly decreased by dietary piperine. The levels of hepatic microsomal cytochrome P450and cytochrome b5were not influenced by any of the dietary spice-active principles. These spice-active principles were also examined for their possible in vitro influence on the components of the hepatic drug-metabolizing enzyme system in rat liver microsomal preparation. Piperine significantly decreased the activity of liver microsomal aryl hydroxylase activity when included in the assay medium at 1 × 10−6 mol/L, 1 × 10−5 mol/L, and 1 × 10−4 mol/L level. Lowered activity of N-demethylase was observed in presence of capsaicin or piperine at 1 × 10−6mol/L in the assay medium. Hepatic microsomal glucuronyl transferase activity was significantly decreased in vitro by addition of capsaicin or piperine. Capsaicin and piperine brought about significant decrease in liver microsomal cytochrome P450when included at 1 × 10−6 mol/L and 1 × 10−5 mol/L, the effect being much higher in the case of piperine. The results suggested that whereas the 3 spice principles have considerable similarity in structure, piperine is exceptional in its influence on the liver drug-metabolizing enzyme system. The study also indicated that a combination of curcumin and capsaicin does not produce any significant additive effect on the liver drug-metabolizing enzyme system.
Down-regulation of calponin destabilizes actin cytoskeletal structure in A7r5 cells
Authors: Dykes Ava C. , Wright Gary L. 
Published: May 2007

The effects of changes in the expression levels of h1 calponin (CaP) on actin cytoskeletal organization were studied in control and phorbol-ester-treated A7r5 smooth muscle cells. Protein association and expression in control and stimulated A7r5 smooth muscle cells were evaluated by Western blotting, laser scanning confocal microscopy (LSCM), and fluorescence resonance energy transfer (FRET) microscopy in cells treated with either 2 × 10−6mol/L TGF-β1 or 2 × 10−5mol/L PDGF-BB to alter h1 calponin expression. Single immunostained samples showed that CaP and α-actin, localized in fibers in unstimulated control A7r5 smooth muscle cells, were translocated to podosomes following treatment with phorbol-12,13-dibutyrate (PDBu). Confocal colocalization imaging and FRET analysis both indicated substantial association of CaP with α-actin in stress fibers of control cells and in podosomes of PDBu-treated cells. PKCα, which showed evidence of only slight association with CaP in control cells, exhibited markedly increased (293%) association in PDBu-contracted cells. Platelet-derived growth factor (PDGF)-BB down-regulated CaP to non-detectable levels, whereas transforming growth factor (TGF)-β1 up-regulated (424%) the expression of CaP without affecting the levels of α-actin or PKCα. PDGF-BB resulted in a significant loss in α-actin stress fibers (–47%) and reduced podosome formation (–69%). By comparison, TGF-β1 had no effect on stress fibers in control cells but also reduced (–70%) podosome formation. The results suggest that CaP could play a major role in the stabilization of actin stress fibers in resting cells and may contribute to podosome formation in PDBu-treated cells.
Non-genomic effects of aldosterone on intracellular ion regulation and cell volume in rat ventricular myocytes
Authors: Matsui Saori , Satoh Hiroshi , Kawashima Hirotaka , Nagasaka Shiro , Niu Chen  Fung , Urushida Tsuyoshi , Katoh Hideki , Watanabe Yasuhide , Hayashi Hideharu 
Published: May 2007

Aldosterone has non-genomic effects that express within minutes and modulate intracellular ion milieu and cellular function. However, it is still undefined whether aldosterone actually alters intracellular ion concentrations or cellular contractility. To clarify the non-genomic effects of aldosterone, we measured [Na+]i, Ca2+ transient (CaT), and cell volume in dye-loaded rat ventricular myocytes, and we also evaluated myocardial contractility. We found the following: (i) aldosterone increased [Na+]i at the concentrations of 100 nmol/L to 10 μmol/L; (ii) aldosterone (up to 10 μmol/L) did not alter CaT and cell shortening in isolated myocytes, developed tension in papillary muscles, or left ventricular developed pressure in Langendorff-perfused hearts; (iii) aldosterone (100 nmol/L) increased the cell volume from 47.5 ± 3.6 pL to 49.8 ± 3.7 pL (n = 8, p < 0.05); (iv) both the increases in [Na+]i and cell volume were blocked by a Na+–K+–2Cl– co-transporter (NKCCl) inhibitor, bumetanide, or by a Na+/H+ exchange (NHE) inhibitor, 5-(N-ethyl-N-isopropyl) amiloride; and (v) spironolactone by itself increased in [Na+]i and cell volume. In conclusion, aldosterone rapidly increased [Na+]i and cell volume via NKCC1 and NHE, whereas there were no changes in CaT or myocardial contractility. Hence the non-genomic effects of aldosterone may be related to cell swelling rather than the increase in contractility.
Bone mass, bone strength, and their relationship in developing CD-1 mice
Authors: Ward Wendy E. , Piekarz Ana V. , Fonseca Debbie 
Published: May 2007

Optimizing nutrition during development may provide effective prevention strategies to protect against osteoporosis during later life. Because the mouse model is commonly used to test nutritional interventions on bone health, the overall objective of this study was to determine how bone develops during the first 4 months of life by assessing bone mass (bone mineral content (BMC) and bone mineral density (BMD)) and biomechanical strength properties such as peak load in male and female CD-1 mice. Bone outcomes were assessed at 1 month intervals from 1 to 4 months of age. Femur and spine BMC and BMD at 3 months were similar to 4 months, indicating that the accumulation of bone mass occurs primarily during the first 3 months of life. In contrast, the timing of changes in peak load, a measure of bone strength, varied by skeletal site. Regression analyses demonstrated that femur BMC is a significant predictor of femur peak load at the femur midpoint and neck. The study findings suggest that nutritional interventions aimed at optimizing peak bone mass to prevent osteoporosis may be most effective during pubertal growth.
Developmental changes in threshold, conduction velocity, and depressive action of lignocaine on dorsal root potentials from neonatal rats are associated with maturation of myelination
Authors: Lizarraga I. , Chambers J.P. , Johnson C.B. 
Published: May 2007

Conduction velocity of primary afferent fibres and blocking actions of local anaesthetics seem to be developmentally regulated. The current work investigated physiological (threshold, conduction velocity, and myelination) and pharmacological (lignocaine (0.0625 to 2 mmol/L) and capsaicin (2 μmol/L)) ontogenic changes on in vitro sciatic nerve-dorsal root preparations from 0- to 12-day-old rats. As rats aged, stimulus intensities necessary to evoke A-fibre thresholds significantly decreased and A-fibre conduction velocities significantly increased. For C-fibres, thresholds significantly increased and conduction velocities significantly varied with age. The blocking potency of lignocaine varied with age: A-fibres from 4-day-old rats and younger were significantly more resistant than those from older rats, and C-fibres were blocked more uniformly amongst ages. Capsaicin significantly depressed C-fibres irrespective of age, and A-fibres were significantly reduced during the first postnatal week only. Myelination significantly increased as rats aged. A-fibre physiological parameters were significantly correlated with both other A-fibre physiological and pharmacological parameters, but C-fibre parameters were not. Peripheral A-fibre transduction mechanisms seem to require time to acquire their full stimulus-response sensitivity, which coincides with development of myelination. In contrast, peripheral C-fibres seem to have mature transduction mechanisms from the first days of postnatal life.
The significance of hydroperiod and stand maturity for pool-breeding amphibians in forested landscapes
Authors: Baldwin R.F. , Calhoun A.J.K. , deMaynadier P.G. 
Published: May 2007

The loss of small seasonal wetlands and adjacent forested habitat is a major threat to pool-breeding amphibians in North America. Identifying environmental correlates of breeding effort (and success) in remaining intact landscapes is a critical first step in conservation planning. Little is known about how pool-breeding amphibian populations respond to fine-scale variations in hydroperiod or neighboring forest structure and composition. We studied these associations for wood frogs ( Rana sylvatica LeConte, 1825) and spotted salamanders ( Ambystoma maculatum (Shaw, 1802)) in a forested New England landscape (southern Maine, USA). We conducted egg mass counts across two seasons at 87 strictly seasonal pools. The influence of hydroperiod and landscape (150 and 500 m scales) habitat characteristics on breeding effort were investigated. Pools with longer hydroperiods (≥18 weeks post breeding) that were relatively isolated from other breeding wetlands (<13 neighboring pools within 150 m and <19 within 500 m) supported larger breeding populations of both wood frogs and spotted salamanders. Salamander breeding populations were largest in relatively mature forests. Naturalized, anthropogenic pools supported comparable levels of breeding effort with that of natural pools. Conservation planning for wood frogs and spotted salamanders should incorporate pools at the longer end of the seasonal hydroperiod gradient.
Feeding habits and trophic niche overlap between sympatric golden jackal (Canis aureus) and red fox (Vulpes vulpes) in the Pannonian ecoregion (Hungary)
Authors: Lanszki J. , Heltai M. , Szabó L. 
Published: May 2007

The feeding ecology of the golden jackal ( Canis aureus L., 1758) and its interspecific trophic relationship with the sympatric red fox (Vulpes vulpes (L., 1758)) was investigated in an area of recent range expansion of the golden jackal in Hungary, central Europe. Diet composition was determined by scat analysis (over 4 years: jackal 814 scats; fox 894 scats). Compared with jackals, foxes consumed more small mammals (mean biomass consumed: jackal 77%; fox 68%) and to a lesser extent plant matter (6% and 18%, respectively). The importance of other prey, such as wild boar ( Sus scrofa L., 1758), cervids, brown hare ( Lepus europaeus Pallas, 1778), birds, reptiles, fish, invertebrates, and domestic animals, was minimal. Both mesocarnivores consumed primarily small animals (<50 g: 92% and 87%, respectively); this implies a typical searching and solitary hunting strategy. The trophic niche breadth of both species was very narrow and the fox proved to be more of a generalist. The food overlap index between the two canids was high (mean, 73%) and varied with the decreasing availability and consumption of small mammals. Based on prey remains found in scats, small-mammal specialization over a 2-year period and seasonal predation upon wild boar piglets (mainly by the jackal), seasonal fruit eating (mainly by the fox), and scavenging on wild or domestic ungulates (both predators) were found.
Yolk hormone levels in the synchronously developing eggs ofParoedura picta, a gecko with genetic sex determination
Authors: Kratochvíl Lukáš , Kubička Lukáš , Landová Eva 
Published: May 2007

Sex steroid hormones of presumably maternal origin have been found in yolk of many oviparous vertebrates. Their effects on behavioural or physiological traits are well documented in birds, but until now are largely unknown in reptiles. The investigations of yolk steroids in reptiles have been focused mainly on species with temperature-dependent sex determination, where steroid levels are suggested to determine the sex of progeny. Here we report initial oestradiol (E2) and testosterone (T) levels in the yolk of the Madagascar ground gecko, Paroedura picta (Peters, 1854), a species with genetic sex determination. The yolk concentration was 0.39 ± 0.02 ng/g (mean ± SE) in E2, whereas the concentration of T was much higher (1.48 ± 0.06 ng/g, mean ± SE). Geckos usually lay two exceptionally large eggs per clutch; vitellogenesis and ovulation of both eggs proceed in phase. Individual two-egg clutches differed considerably in E2 and T levels. A clutch mean of E2 levels varied from 0.22 to 0.53 ng/g, whereas T levels varied from a clutch mean of 1.02 to 1.99 ng/g. Both eggs in a clutch possessed very similar levels of E2 and T. Initial yolk steroid levels thus presumably reflect maternal conditions during egg formation rather than differential allocation of hormones according to offspring sex.
Using n-alkane markers to estimate forage intake of mule deer
Authors: Kuzyk G.W. , Hudson R.J. 
Published: May 2007

Dry matter intake (DMI) of free-ranging mule deer ( Odocoileus hemionus (Rafinesque, 1817)) in the aspen parkland of east-central Alberta was estimated using the double n-alkane ratio and bite count methods. Eleven female mule deer were given an intraruminal capsule containing synthetic n-alkanes and released into 4–8 ha paddocks. Known concentration of even-chained carbon (C32) was released from the capsules and recovered 7–10 days later from freshly voided faeces. Odd carbon chains of adjacent length (C31:C33) were extracted from vegetation samples gathered during behavioural observations of four tame deer. Calculations from the pairings (C31:C32; C33:C32) provided estimates of DMI that ranged from 1.29 to 2.73 kg/day. DMI was highest during autumn, possibly to prepare for increased energy demands for the upcoming winter. No differences were found in seasonal or annual comparisons of bite rates, but bite sizes differed in all comparisons, suggesting bite size was a critical factor affecting consumption rates for mule deer on northern ranges. Maximum bite sizes rose from 49 ± 5 mg/bite in July to 213 ± 58 mg/bite in October. Maximum consumption rates were in October of both years (3.6–4.4 g/min) and occasionally approached theoretical maxima (14.3–15.6 g/min).
Geographic variation in nesting behavior and reproductive biology of an insular iguana (Cyclura cychlura)
Authors: Knapp C.R. , Iverson J.B. , Owens A.K. 
Published: May 2007

Intraspecific comparisons among geographically separated populations of wide-ranging species are particularly useful in elucidating variation in behavioral and reproductive life histories resulting from proximate and ultimate causes. From 2001 to 2004, we investigated geographic variation in nesting behavior and reproductive biology of a large-bodied Bahamian iguana ( Cyclura cychlura Cuvier, 1829) inhabiting two distinct island systems varying in area, topography, and rainfall. Studies of C. cychlura cychlura were conducted on Andros Island (approx. 6000 km2; annual rainfall 1100 to 1300 mm) and the results were compared with those for C. cychlura inornata Barbour and Noble, 1916 inhabiting two cays (each <4 ha; annual rainfall <600 mm) in the northern Exuma Island chain (approx. 140 km distant). Female iguanas from Andros Island initiated oviposition 5 to 6 weeks earlier than females from the Exumas. The Andros Island population deposited eggs primarily in termitaria, whereas the lizards in the Exumas deposited eggs in subterranean sand chambers. Female iguanas from Andros deposited significantly more eggs per clutch, heavier total clutches, and wider eggs than conspecifics from the Exumas. Despite egg size differences, hatchling snout–vent length and body mass per clutch did not differ significantly between the Andros and Exuma populations. Our results support the hypothesis that proximate environmental factors play an important role in determining geographic variation associated with not only reproductive output but also reproductive behavior.