Rescue of High Glucose Impairment of Cultured Human Osteoblasts Using Cinacalcet and Parathyroid Hormone.

Patients with type 2 diabetes mellitus (T2DM) experience a higher risk of fractures despite paradoxically exhibiting normal to high bone mineral density (BMD). This has drawn into question the applicability to T2DM of conventional fracture reduction treatments that aim to retain BMD. In a primary human osteoblast culture system, high glucose levels (25 mM) impaired cell proliferation and matrix mineralization compared to physiological glucose levels (5 mM). Treatment with parathyroid hormone (PTH, 10 nM), a bone anabolic agent, and cinacalcet (CN, 1 µM), a calcimimetic able to target the Ca2+-sensing receptor (CaSR), were tested for their effects on proliferation and differentiation. Strikingly, CN+PTH co-treatment was shown to promote cell growth and matrix mineralization under both physiological and high glucose conditions. CN+PTH reduced apoptosis by 0.9-fold/0.4-fold as measured by Caspase-3 activity assay, increased alkaline phosphatase (ALP) expression by 1.5-fold/twofold, increased the ratio of nuclear factor κ-B ligand (RANKL) to osteoprotegerin (OPG) by 2.1-fold/1.6-fold, and increased CaSR expression by 1.7-fold/4.6-fold (physiological glucose/high glucose). Collectively, these findings indicate a potential for CN+PTH combination therapy as a method to ameliorate the negative impact of chronic high blood glucose on bone remodeling.

Virtual water flows under projected climate, land use and population change: the case of UK feed barley and meat.

The flow of water through food commodity trade has been rationalized in the virtual water concept. Estimates of future virtual water flows under climate, land use, and population changes could have instrumental value for policy and strategic trade decisions. This paper estimated the virtual water flows associated with feed barley and meat imports to the UK under projected climate, land use, and population changes from the 2030s to the 2050s. The results show that future virtual water inflows associated with barley imports to balance domestic deficits are larger than total volume of water used in domestic barley production in the UK. Mean virtual water associated with total UK barley production ranged from 206 to 350 million m3. This is much less than the mean total virtual water associated with barley imports (if total barley produced in the UK is used for feed), which ranged from 2.5 to 5.6 billion m3 in the 2030s to the 2050s for all land use and climate change scenarios. If domestic barley production is distributed to the different end uses, the total virtual water inflows associated with imports to balance domestic feed barley supply could be as high as 7.4 billion m3. Larger virtual water inflows (as high as 9.9 billion m3) were associated with feed barley equivalent meat imports. While the UK barley production would be entirely green, imports of either barley or meat would result in large blue water inflows to the UK. Virtual water inflows increased across the time slices for all emissions scenarios, indicating weak effectiveness of yield or productivity gains to moderate virtual water inflows. While increase in yield and land allocated to barley production should be adaptive targets, the UK needs to take policy and strategic actions to diversify trade partners and shift imports away from countries where blue water flows can exacerbate existing or potential water stresses.

Matrix metalloproteinase distribution during early corneal wound healing.

AIM: To compare matrix metalloproteinase (MMP) localisation in anterior keratectomy (AK) and lamellar keratectomy (LK) wounds. METHODS: Wounds were produced in one eye of 24 rabbits. The AK wounds were made to approximately 120 microm in depth and then allowed to re-epithelialise. The LK wounds were of similar depth, but the anterior stroma and epithelium were replaced after a second deeper keratectomy had been performed. Immunohistochemistry was used to localise the MMP-1, -2, -3, and -9 at intervals from 4 h to 14 days following surgery. The contralateral eyes acted as controls. RESULTS: After an AK wound MMP-1 was present at the leading edge of migrating epithelium after 18 h, while MMP-2 and -9 were localised behind the advancing epithelial edge. The presence of these enzymes rapidly fell to low levels after epithelial closure. There was only faint MMP-3 localisation between days 3 and 7. After an LK wound, MMP-1, -3, and -9 were not detected in the stromal interface, but MMP-2 was present at all time points. CONCLUSIONS: This study suggests that after an AK wound, MMP-1 is a key mediator of epithelial migration, while MMP-2 and -9, and to a lesser extent MMP-3, may participate in the remodelling of corneal stroma and the reformation of epithelial basement membrane. In contrast, an LK wound results in a much lower stimulus for MMP activation. The action of MMP-2 in stromal repair is thus partly independent of epithelial injury.

Microcystic adnexal carcinoma of the eyebrow.

PURPOSE: To describe a case of the largest reported microcystic adnexal carcinoma of the eyebrow in an 89-year-old woman and to review the literature regarding the periorbital occurrence of this tumor. METHODS: Case report and literature review. RESULTS: This case was treated with primary excision and radiotherapy, with no clinical signs of recurrence in the past 6 months. CONCLUSIONS: Microcystic adnexal carcinoma is a rare tumor; however, because of its aggressive local infiltration, ophthalmologists should consider this diagnosis and complete surgical excision. Long-term data are needed to establish outcomes from the different treatment options.

Intraocular penetration of tamoxifen.

OBJECTIVE: To document ocular penetration of oral tamoxifen in patients being administered systemic therapy by measuring intraocular and serum levels of the drug in a series of patients undergoing elective ocular surgery. DESIGN: Nonrandomized, prospective, comparative trial. PARTICIPANTS: Twenty-one eyes of 21 patients undergoing elective ocular surgery (cataract extraction or vitrectomy). Twenty patients were using the antiestrogen, tamoxifen, and one participant was not. Nine patients were excluded in the final analysis because of inadequate sample size. INTERVENTION: Preoperative serum samples and perioperative aqueous samples, vitreous samples, or both were obtained for each patient, and these were analyzed for tamoxifen and its metabolites. Dilated fundus examination was performed before surgery on all patients. MAIN OUTCOME MEASURES: Evidence of tamoxifen, its metabolites, or both in the samples. RESULTS: Tamoxifen was detected in all analyzed serum samples (range, 82.4-290.0 ng/ml.) from patients taking the medication and was found to have penetrated into both vitreous (range, 0.5-7.8 ng/ml) and aqueous (range, 0.5-3.9 ng/ml) cavities. No relationship was found between serum and intraocular levels. CONCLUSIONS: This study shows that tamoxifen penetrates intraocular fluids to varying degrees. The drug levels in aqueous and vitreous do not appear to correlate with serum levels. Evidence of tamoxifen retinopathy or keratopathy was not seen.

Anterior uveitis and its relation to stress.

BACKGROUND/AIMS: Idiopathic recurrent acute anterior uveitis (RAAU) is a common reason for attendance at ophthalmic casualty departments. Patients who suffer with this condition may have multiple recurrent episodes which are often debilitating and necessitate time off work. If recurrences are identified early and treatment initiated rapidly, the inflammation can be minimised and settles quickly on topical treatment with a speedy functional recovery by the patient. It has been our clinical impression that some patients with RAAU relate recurrences of inflammation to psychological factors. Therefore stress could be a trigger factor for recurrence, and at such times, patients should be alert to the early signs of uveitis and seek prompt examination by an ophthalmologist. This study tests the hypothesis that stressful life events are associated with the onset of RAAU. METHODS: The number of stressful life events in patients presenting to the casualty department with RAAU in the month immediately preceding symptom onset was compared with a control group of patients with other ocular problems taken from the casualty department using the Holmes and Rahe scale and the Spielberger state-trait anxiety inventory. RESULTS: 35 patients with RAAU did not report a higher number of stressful life events or higher levels of anxiety compared with 29 controls in this study on both Holmes and Rahe scale and Spielberger state-trait anxiety inventory. Scores for both groups were comparable with those published for normal adults of the same age and sex. CONCLUSION: Stress was not shown in this study to be involved in triggering the recurrence of idiopathic acute anterior uveitis.

Ectopic expression of a tomato 9-cis-epoxycarotenoid dioxygenase gene causes over-production of abscisic acid.

The tomato mutant notabilis has a wilty phenotype as a result of abscisic acid (ABA) deficiency. The wild-type allele of notabilis, LeNCED1, encodes a putative 9-cis-epoxycarotenoid dioxygenase (NCED) with a potential regulatory role in ABA biosynthesis. We have created transgenic tobacco plants in which expression of the LeNCED1 coding region is under tetracycline-inducible control. When leaf explants from these plants were treated with tetracycline, NCED mRNA was induced and bulk leaf ABA content increased by up to 10-fold. Transgenic tomato plants were also produced containing the LeNCED1 coding region under the control of one of two strong constitutive promoters, either the doubly enhanced CaMV 35S promoter or the chimaeric 'Super-Promoter'. Many of these plants were wilty, suggesting co-suppression of endogenous gene activity; however three transformants displayed a common, heritable phenotype that could be due to enhanced ABA biosynthesis, showing increased guttation and seed dormancy. Progeny from two of these transformants were further characterized, and it was shown that they also exhibited reduced stomatal conductance, increased NCED mRNA and elevated seed ABA content. Progeny of one transformant had significantly higher bulk leaf ABA content compared to the wild type. The increased seed dormancy was reversed by addition of the carotenoid biosynthesis inhibitor norflurazon. These data provide strong evidence that NCED is indeed a key regulatory enzyme in ABA biosynthesis in leaves, and demonstrate for the first time that plant ABA content can be increased through manipulating NCED.

The use of corticosteroids for choroidal neovascularisation in young patients.

PURPOSE: To investigate the role of systemic corticosteroids in the treatment of sight-threatening choroidal neovascularisation (CNV) in patients with punctate inner choroidopathy (PIC) and multifocal inner choroiditis (MIC). METHODS: Twelve eyes of 10 patients with evidence of PIC or MIC with recent visual symptoms were identified. All eyes had CNV within the foveal avascular zone on fundus fluorescein angiography (FFA). Systemic oral prednisolone at an initial dose of 1 mg/kg (60-80 mg) was given for 3-5 days and the dose was subsequently tapered. Changes in best corrected visual acuity and leakage on FFA were recorded during follow-up. Systemic side-effects of the corticosteroids were monitored. RESULTS: In 10 of 12 eyes vision improved or stabilised. Leakage on FFA resolved in 9 eyes and was reduced in 3. Four patients required more than one course of oral corticosteroids. One patient was maintained on low-dose oral corticosteroids for recurrent CNV activity. No systemic complications from the treatment were observed. CONCLUSION: A course of oral corticosteroids in healthy young patients with subfoveal CNV in PIC or MIC may reduce subretinal vascular leakage and stabilise vision when no other proven treatment option is available.

Culture of human osteoblasts on demineralised human bone. Possible means of graft enhancement.

We cultured human osteoblasts from trabecular bone explants and confirmed their phenotype by alkaline phosphatase assay, increased cyclic adenosine monophosphate production in response to prostaglandin E2 and radiographic micro-analysis of nodules of calcification. The osteoblasts were seeded on to demineralised human bone fragments and examined at ten-day intervals over a 50-day period by scanning electron microscopy. During this time the bank bone became progressively repopulated by the cultured osteoblasts. This system may offer a means of graft enhancement in elective orthopaedic and maxillofacial surgery by delivery of cultured autologous human osteoblasts to bone defects.

The antimicrobial activity of protamine and polybrene.

Polybrene and protamine have broad antimicrobial activity and may be useful as topical agents.