Metformin pretreatment potentiates the antiproliferative action of doxorubicin against breast cancer.

OBJECTIVES: The present study aimed to evaluate the effect of metformin pretreatment on the potentiation of antiproliferative action of doxorubicin against breast cancer. MATERIAL AND METHODS: Female Wistar rats were administered with 7,12-Dimethylbenz(a)anthracene (DMBA) (35mg) in 1mL olive oil subcutaneously beneath the mammary gland. Animals were pretreated with metformin (Met) 200mg/kg two weeks before DMBA administration. DMBA control groups received doxorubicin (Dox) (4mg/kg and 2mg/kg), Met (200mg/kg) alone and in combination with Dox (4mg/kg). Met pre-treated DMBA control groups received Dox 4mg/kg and 2mg/kg. RESULTS: Met pre-treated groups treated with Dox exhibited a decrease in tumor incidence, tumor volume and increased survival rate than the DMBA group. Organ-to-body weight ratios and histopathology of heart, liver and lungs of Met pre-treated groups treated with Dox showed lesser toxicity than Dox treated DMBA control groups. There was a noteworthy decrease in malondialdehyde levels and a substantial increase in the levels of reduced glutathione together with a significant decrease in the levels of inflammatory markers like IL-6, IL-1ß and NF-κB in Met pre-treated groups treated with Dox. Histopathology of breast tumors revealed better control of tumors in Met pre-treated groups treated with Dox than DMBA control group. Immunohistochemistry and real-time PCR data revealed a significant reduction in Ki67 expression in Met pre-treated groups treated with Dox as compared to the DMBA control group. CONCLUSION: The present study suggests that metformin pretreatment potentiates the antiproliferative action of doxorubicin against breast cancer.

Winter Deployment 14 and 15: an audit of injury and illness rates in an Arctic environment.

INTRODUCTION: Arduous military training in a cold weather environment is likely to lead to a variety of injuries to the population at risk (PAR). This paper examines injury rates and medical presentations over the two years of Winter Deployments in 2014 and 2015 (WD14 and WD15) and proposes recommendations for future WDs. METHODS: Data on injury rates, number of aeromedical evacuations, and number of days of restricted duties allocated were collected prospectively for all patients presenting to Asegarden Medical Centre, Norway, during WD14 and WD15. The data were calculated as a percentage of the total PAR on each deployment to allow meaningful comparison. RESULTS: During WD14, 22.8% of the PAR presented to the Medical Centre compared to 26.9% during WD15. WD15 saw a reduction in the presentation of musculoskeletal (MSK) injuries, cold weather (CW) injuries and burns. Skin problems and diarrhoea and vomiting (D&V) remained similar in both years. An increase in dental and other presentations was seen in WD15. A reduction in the overall aeromedical evacuations and number of patients requiring a light duties (LD) chit was seen during WD15. CONCLUSION: WD15 has seen a decrease in injury rates, the number of aeromedical evacuations and LD chits issued. It is difficult to know whether these changes are a result of improved medical support, training or equipment. The liaison between the command, medical and training elements has led to improvements and should now concentrate on ways to further reduce injury rates whilst maximising arduous training benefits in an Arctic environment.

Certifications for sight impairment due to age related macular degeneration in England.

OBJECTIVES: To examine variability across England in certification rates for age related macular degeneration (AMD) between 1st April 2011 and 31st March 2012. STUDY DESIGN: Cross-sectional survey. METHODS: An electronic version of the CVI, the ECVI, was used at the Certifications Office, London, to transfer information from paper based certificates into a database. The electronic certifications data set was queried for all certificates completed in England between April 1st 2011 and March 31st 2012 with the main cause of certifiable visual loss being AMD or with the main cause of certifiable visual loss being multiple pathology but a contributory cause being AMD. Data were explored by type of AMD, visual status, age and sex and then directly standardized rates were computed by English region. RESULTS: The Certifications Office received 23,616 CVIs for England between April 2011 and March 2012, of which 10,481 (44%) were people certified severely sight-impaired (blind) (SSI) and 12,689 (54%) were certified as sight-impaired (partial sight) (SI). The remainder did not have visual status classified. AMD contributed to 11546 causes of certification on the CVI forms during this period, 53% of forms being for geographic atrophy (GA)/dry AMD which is currently mostly untreatable. The median (interquartile) age at certification for AMD was 86 (81, 90) years and women were more commonly certified than men (66%). Considerable variability was seen across English regions, although there was consistency in that GA was the more common form in all areas. CONCLUSIONS: There is considerable regional variability in CVI rates in England, which are not attributable to differences in age or sex. Reasons for such variability need examination yet this should not undermine the value of these data in terms of describing those newly registered with sight impairment due to AMD who are predominantly female and over 85 years of age.

Prediction of visual function from automatically quantified optical coherence tomography biomarkers in patients with geographic atrophy using machine learning.

Geographic atrophy (GA) is a vision-threatening manifestation of age-related macular degeneration (AMD), one of the leading causes of blindness globally. Objective, rapid, reliable, and scalable quantification of GA from optical coherence tomography (OCT) retinal scans is necessary for disease monitoring, prognostic research, and clinical endpoints for therapy development. Such automatically quantified biomarkers on OCT are likely to further elucidate structure-function correlation in GA and thus the pathophysiological mechanisms of disease development and progression. In this work, we aimed to predict visual function with machine-learning applied to automatically acquired quantitative imaging biomarkers in GA. A post-hoc analysis of data from a clinical trial and routine clinical care was conducted. A deep-learning automated segmentation model was applied on OCT scans from 476 eyes (325 patients) with GA. A separate machine learning prediction model (Random Forest) used the resultant quantitative OCT (qOCT) biomarkers to predict cross-sectional visual acuity under standard (VA) and low luminance (LLVA). The primary outcome was regression coefficient (r2) and mean absolute error (MAE) for cross-sectional VA and LLVA in Early Treatment Diabetic Retinopathy Study (ETDRS) letters. OCT parameters were predictive of VA (r2 0.40 MAE 11.7 ETDRS letters) and LLVA (r2 0.25 MAE 12.1). Normalised random forest feature importance, as a measure of the predictive value of the three constituent features of GA; retinal pigment epithelium (RPE)-loss, photoreceptor degeneration (PDR), hypertransmission and their locations, was reported both on voxel-level heatmaps and ETDRS-grid subfields. The foveal region (46.5%) and RPE-loss (31.1%) had greatest predictive importance for VA. For LLVA, however, non-foveal regions (74.5%) and PDR (38.9%) were most important. In conclusion, automated qOCT biomarkers demonstrate predictive significance for VA and LLVA in GA. LLVA is itself predictive of GA progression, implying that the predictive qOCT biomarkers provided by our model are also prognostic.

Aging and antimicrobial immunity. Impaired production of mediator T cells as a basis for the decreased resistance of senescent mice to listeriosis.

Immunity to infection of mice with the facultative, intracellular pathogen Listeria monocytogenes was employed as a model system to investigate the immunological basis for the age-associated decline in anti-microbial immunity. In response to a sublethal immunizing infection, aged (24-mo old or more) mice displayed a smaller increase in spleen weight, spleen cellularity, and splenic T cell content than young (3- to 4-mo-old) mice. Aged mice also generated a smaller number of anti-Listeria protective T cells at the time of a peak response, in that their spleen cells were 1,000-fold less protective than equivalent numbers of spleen cells from the young donors, even when enriched T cell populations were employed. These results suggest that the impaired ability of aged mice to produce protective T cells is mainly responsible for decreased resistance of these mice to infection with Listeria.

Aging and antimicrobial immunity. Lowered efficiency of protective T cells as a contributing factor for the decreased resistance of senescent mice to listeriosis.

Experimental murine listeriosis was used as a model to investigate the immunological basis for the age-associated decline in antimicrobial immunity. The reduced capacity of protective T cells from Listeria-immune senescent mice to adoptively immunize normal syngeneic recipients could not be attributed to inhibition of their activity by suppressor cells. Radiolabeled enriched splenic T cells from Listeria-immune young or senescent donors exhibited an identical distribution pattern after an intravenous infusion into young recipients. Moreover, cells from Listeria-immune young donors showed markedly greater protective capacity than cells from senescent immune donors whether the cells were transferred to young or senescent recipients. Dose-response analysis of protective T cells revealed that in response to immunizing infection (a) senescent mice generated 10-fold fewer protective T cells, and (b) protective T cells from senescent mice were 100-fold less efficient than cells from young mice.

Enhanced production of murine interferon gamma by T cells generated in response to bacterial infection.

Spleen cell cultures derived from animals infected 6 d earlier with Listeria monocytogenes produced 10-20-fold more murine interferon gamma (MuIFN gamma) than spleen cells from nonimmune mice in response to stimulation with T cell mitogens. A striking temporal association was found between the enhanced synthesis of MuIFN gamma and the development of anti-Listeria immunity in that both the potential for increased MuIFN gamma production and the generation of Listeria-protective T cells developed and then decayed in unison. Treatment of spleen cells with monoclonal anti-Thy-1.2 plus complement virtually abolished the ability of cells from Listeria-immune mice to synthesize MuIFN gamma. The T cells producing MuIFN gamma were found to be more susceptible to complement-mediated lysis with monoclonal anti-Lyt-1.2 than with monoclonal anti-Lyt-2.2. The production of MuIFN gamma was not affected by treating spleen cells with anti-IgG antisera or with a monoclonal antibody directed against I-A specificities. MuIFN gamma was detected 4 h after the beginning of mitogenic stimulation of spleen cell cultures, and peak levels of MuIFN gamma were reached by 18 h. The IFN synthesized by mitogen-induced spleen cells derived from Listeria-immune mice were relatively labile at pH 2.0 and neutralized by a rabbit anti-MuIFN gamma serum but not by an antiserum having specificities for MuIFN alpha and MuIFN beta. The apparent molecular weight of the MuIFN gamma, as estimated by molecular sieving on a Bio-gel P-60 column, was estimated to be 38,000, and the isoelectric point as determined by chromatofocusing was extremely heterogeneous, ranging between pH 5.0 and pH 7.0.

Age-related macular degeneration: diagnosis and management.

BACKGROUND: Age-related macular degeneration (AMD) is a leading cause of blind registration in Western Europe and the third leading cause of blindness worldwide. METHODS: The management of AMD is discussed with a review of current and new treatments. RESULTS: Although there is no treatment for advanced dry AMD (geographic atrophy), there have been considerable advances in the management of neovascular AMD (nAMD). Established therapies for nAMD include laser photocoagulation and photodynamic therapy (PDT), but these have largely been superseded by agents which block the action of vascular endothelial growth factor (anti-VEGF agents). Current preventative strategies involve cessation of smoking and use of specific nutritional supplements to reduce the risk of developing nAMD. CONCLUSIONS: There have been exciting advances in the treatment of nAMD and increased understanding of the genetics and pathogenic mechanisms involved will hopefully lead to the development of new therapies in the future.

Risk of geographic atrophy in age-related macular degeneration patients treated with intravitreal anti-VEGF agents.

Anti-vascular endothelial growth factor (VEGF) intravitreal agents are the only successful treatment for wet age-related macular degeneration (AMD). However, there are emerging signals that anti-VEGF treatment can potentially increase development of geographic atrophy (GA). Histopathologic, animal, and clinical studies support this hypothesis although direct proof of a relationship between GA and use of anti-VEGF agents in neovascular AMD is not yet established. This review presents current evidence supporting an association between anti-VEGF therapy and progression of geographic atrophy. The need of exploring alternative methods of treating AMD is indirectly but clearly emphasized.

Measures of socioeconomic status and self-reported glaucoma in the U.K. Biobank cohort.

PURPOSE: To determine ocular, demographic, and socioeconomic associations with self-reported glaucoma in the U.K. Biobank. METHODS: Biobank is a study of U.K. residents aged 40-69 years registered with the National Health Service. Data were collected on visual acuity, intraocular pressure (IOP), corneal biomechanics, and questionnaire from 112,690 participants. Relationships between ocular, demographic, and socioeconomic variables with reported diagnosis of glaucoma were examined. RESULTS: In all, 1916 (1.7%) people in U.K. Biobank reported glaucoma diagnosis. Participants reporting glaucoma were more likely to be older (mean 61.4 vs. 56.7 years, P<0.001) and male (2.1% vs. 1.4%, P=0.001). The rate of reported glaucoma was significantly higher in Black (3.28%, P<0.001) and Asian (2.14%, P=0.009) participants compared with White participants (1.62%, reference). Cases of reported glaucoma had a higher mean IOP (18 mm Hg both eyes, P<0.001), lower corneal hysteresis (9.96 right eye, 9.89 left eye, P<0.001), and lower visual acuity (0.09 logMAR right eye, 0.08 logMAR left eye, P<0.001) compared with those without (16 mm Hg both eyes, hysteresis 10.67 right eye, 10.63 left eye, 0.03 logMAR right eye, 0.02 logMAR left eye). The mean Townsend deprivation index was -0.72 for those reporting glaucoma and -0.95 for those without (P<0.001), indicating greater relative deprivation in those reporting glaucoma. Multivariable logistic regression showed that people in the lowest income group (<£18,000/year) were significantly more likely to report a diagnosis of glaucoma compared with any other income level (P<0.01). We observed increasing glaucoma risk across the full range of income categories, with highest risk among those of lowest income, and no evidence of a threshold effect. CONCLUSIONS: In a large U.K. cohort, individuals reporting glaucoma had more adverse socioeconomic characteristics. Study of the mechanisms explaining these effects may aid our understanding of health inequality and will help inform public health interventions.

Aflibercept in wet AMD beyond the first year of treatment: recommendations by an expert roundtable panel.

This paper provides expert recommendations on administration of aflibercept in wet age-related macular degeneration (AMD) after Year 1 (Y1), based on a roundtable discussion held in London, UK in November 2014. The goals of treatment after Y1 are to maintain visual and anatomical gains whilst minimising treatment burden and using resources effectively. The treatment decision should be made at the seventh injection visit (assuming the label has been followed) in Y1, and three approaches are proposed: (a) eyes with active disease on imaging/examination but with stable visual acuity (VA) at the end of Y1 should continue with fixed 8-weekly dosing; (b) eyes with inactive disease on imaging/examination and stable VA should be managed using a 'treat and extend' (T&E) regimen. T&E involves treating and then extending the interval until the next treatment, by 2-week intervals, to a maximum of 12 weeks, provided the disease remains inactive. If there is new evidence of disease activity, treatment is administered and the interval to the next treatment shortened; and (c) if there has been no disease activity for ≥3 consecutive visits, a trial of monitoring without treatment may be appropriate, initiated at the end of Y1 or at any time during Y2. Where possible, VA testing, OCT imaging and injection should be performed at the same visit. The second eye should be monitored to detect fellow eye involvement. In bilateral disease, the re-treatment interval should be driven by the better-seeing eye or, if the VA is similar, the eye with the more active disease.

Inhibition and inactivation of presynaptic cholinergic markers using redox-reactive choline analogs.

Inhibition and inactivation of two presynaptic cholinergic "markers", choline acetyltransferase and high affinity choline transporter, has been investigated using inhibitors designed with a redox-reactive catechol tethered to a quaternary ammonium group. Two quaternary ammonium alkyl-substituted catechols, 3[(trimethylammonio)methyl]catechol (TMC, 1) and N,N-dimethylepinephrine (catecholine, 2) were shown to bind weakly and noncompetitively to bovine choline acetyltransferase yet inactivated the enzyme in a time course consistent with the involvement of early intermediates in the spontaneous oxidation of these catechols. Both agents also inhibited high-affinity choline uptake. The time course of TMC and catecholine spontaneous oxidation-dependent inactivation of high affinity choline uptake sites was slower than, if it occurred at all, the spontaneous degradation of measurable choline transport in synaptosomes. When compared with inhibition of uptake of other neurotransmitters, it was shown that catecholine demonstrated more selectivity than TMC toward inhibition of choline transport. Km (microM) and Vmax (pmol/min per mg of protein) were measured for high affinity transport of choline, dopamine, and serotonin and were observed to be Km = 2.04 +/- 0.31, Vmax = 22 +/- 1; Km = 1.4, Vmax = 53; and Km = 0.15, Vmax = 23, respectively, in good agreement with published literature values. Ki's (mM) for catecholine and TMC, calculated from experimentally determined IC50's, were for catecholine 0.13 +/- 0.06, 0.53 +/- 0.09, and 0.39 +/- 0.10, and for TMC 0.06 +/- 0.03, 0.09 +/- 0.03, and 0.09 +/- 0.08, for choline, dopamine, and serotonin transport, respectively. In vivo studies using catecholine suggest that this compound impairs learning ability associated with long-term memory. Thus, catecholine represents a lead compound in a potential series of redox-reactive choline analogs, which may become useful irreversible antagonists of the critical cholinergic macromolecular targets underlying cholinergic hypofunction in disorders such as Alzheimer's disease.

Multiple congenital malformations in two sibs reminiscent of hydrolethalus and pseudotrisomy 13 syndromes.

We report on two sibs, born to consanguineous parents, with defects of the midline including cleft lip and palate, flat nose, hypotelorism, and dysgenesis of corpus callosum, in addition to short limbs, radiolucent tibial notch, digital anomalies, ambiguous genitalia, and hypopituitarism. In spite of the similarities between this condition and the hydrolethalus and pseudotrisomy 13 syndromes, our patients had neither preaxial nor postaxial polydactyly, but had previously undescribed bilateral radiolucent tibial notch, which is not known to be part of those two syndromes. The cases presented here may very well represent a new autosomal recessive syndrome.

Correlation of in vivo topical efficacies with in vitro predictions using acyclovir formulations in the treatment of cutaneous HSV-1 infections in hairless mice: an evaluation of the predictive value of the C* concept.

The purpose of this study was to carry out an extensive examination of the C* concept for prediction of the topical antiviral efficacies of acyclovir (ACV) formulations in a hairless mouse model for the treatment of cutaneous herpes simplex virus type-1 (HSV-1) infections. This method is based on estimation of the free drug concentration at the target site (C*), which is presumed to be the basal cell layer of the epidermis. Five different formulations (containing 5% ACV) were examined in a finite dose multiple dosing regimen (twice a day application) to simulate the clinical situation. For determination of C*, in vitro ACV fluxes across the hairless mouse skin were measured in an in vivo-in vitro experimental design that approximated the in vivo antiviral treatment protocol. Then, the in vivo antiviral efficacies were measured using a 1-day delayed (after HSV-1 virus inoculation) 4-day treatment protocol. 10 microL/cm2 dose of ACV formulation was applied every 12 h for 4 days after which the lesions were scored and efficacies were calculated. Our results indicate that, over a wide range of efficacies, the predictions based on C* (estimated from the experimental fluxes) are in good agreement with the in vivo antiviral efficacies. These studies, therefore, support the validity of the C* concept for various ACV formulations and suggest that the C* approach has potential for future practical situations.

Antigenic evaluation of Mycobacterium lepraemurium.

Immunodiffusion analysis of Mycobacterium lepraemurium indicated the presence of at lease six antigens. Comparative analysis of the M. lepraemurium antigen-antibody system with similar systems established for other mycobacterial species, showed that M. lepraemurium shared up to two antigens with other species. Although our observations are in accord with some of the studies on the antigenic mosaic of M. lepraemurium, they are in disagreement with the observations of Stanford (1973) concerning a close serological relationship of this organism to M.avium. This incompatiblity cannot be explained satifactorily at present.

Immunological studies on leprosy: separation and evaluation of the antigens of Mycobacterium leprae.

Chromatographically separated antigens of Mycobacterium leprae were tested for their ability to elicit skin reactions in guinea-pigs sensitised with homologous and heterologous mycobacteria. Of the three antigen-positive fractions obtained, one showed specific activity and the other two cross-reactivity, as indicated by studies of hypersensitivity and passive cutaneous anaphylaxis. The fraction exhibiting specificity contained only one antigen, which was protein in nature, whereas the other two fractions contained more than one antigen and possessed both protein and polysaccharide constituents. Because the single-antigen-containing fraction showed both positive skin and PCA reactivity, the suggestion is made that this fraction may contain either an antigen with two determinants or may contain two antigens that are not easily distinguishable by immunodiffusion methods.

Orbital and intracranial haemangiopericytoma. Case report with a short review.

A case of haemangiopericytoma (HPC) in a 50-year-old male occurring in the orbit and the adjoining anterior and middle cranial fossa, studied by ultrasound, angiography and computed tomographic scans, is presented. A short review of the radiological features is given. This is the first case of this rare tumor studied by all the three aforementioned radiodiagnostic modalities; and one of the few reports of its computed tomographic (CT) appearances in the literature. The marked and persistent enhancement of this tumour with the polycyclic nature of its well-defined margins as seen on CT is emphasized. It is suggested that dynamic scanning may assist in differentiating this tumour from meningioma with which it is often confused.

Osteopetrosis: some unusual radiological features with a short review.

The radiological features of 27 cases of osteopetrosis were analysed retrospectively. The common features of generalized sclerosis of bones; with metaphyses showing characteristic widening, multiple transverse striations, cortical thickening and medullary calcifications as well as fractures, are seen in most cases. In addition to these changes, a number of rare features of osteopetrosis are seen, viz: medial and symmetrical metaphyseal cortical defects in the long bones (5 cases), excessive diaphyseal radiodense periosteal new bone formation (5 cases), bone-in-bone appearances (5 cases), and the presence of intracerebral and meningeal calcifications in 7 cases. The significance of these intracranial calcifications as a component of a particular autosomal recessive syndrome in which renal tubular acidosis and carbonic anhydrase II deficiency may co-exist, is discussed.

Cutis verticis gyrata: its computed tomographic demonstration in acromegaly.

A retrospective review of the 17 cases of acromegaly, recorded in the hospital and with available CT scans was undertaken in order to determine the presence and of cutis verticis gyrata (CVG) frequency, and the spectrum of other associated radiographic appearances of CVG. The hormone levels were analysed, and the histopathology of the surgical specimens reviewed. Five cases were uncovered. In these, the scalp in CVG was markedly thickened with convoluted, gyriform or cog-wheel appearances. There was no correlation in the age, sex, duration of symptoms or the hormone levels in these two groups of acromegalics: with or without CVG. All cases were histologically pituitary adenoma. It is concluded that CVG is not uncommon in acromegaly. Its presence on a CT scan should caution the radiologist to the presence of pituitary adenoma or any of the other neurological causes of CVG.

Computed tomographic changes of the brain in toxaemia of pregnancy.

Four cases of toxaemia of pregnancy examined with computed tomography scans of the brain are reported. A review of the literature reveals 19 other cases with previously reported CT brain scans. The review shows intracerebral oedema as the main finding. Haemorrhage, massive or punctate was noted in four cases. The pathogenesis of the CT changes and the clinico-radiological correlation of the visual disturbances are discussed.