VEGF dose controls the coupling of angiogenesis and osteogenesis in engineered bone

Vascular endothelial growth factor-A (VEGF) physiologically regulates both angiogenesis and osteogenesis, but its application in bone tissue engineering led to contradictory outcomes. A poorly understood aspect is how VEGF dose impacts the coordination between these two processes. Taking advantage of a unique and highly tunable platform, here we dissected the effects of VEGF dose over a 1,000-fold range in the context of tissue-engineered osteogenic grafts. We found that osteo-angiogenic coupling is exquisitely dependent on VEGF dose and that only a tightly defined dose range could stimulate both vascular invasion and osteogenic commitment of progenitors, with significant improvement in bone formation. Further, VEGF dose regulated Notch1 activation and the induction of a specific pro-osteogenic endothelial phenotype, independently of the promotion of vascular invasion. Therefore, in a therapeutic perspective, fine-tuning of VEGF dose in the signaling microenvironment is key to ensure physiological coupling of accelerated vascular invasion and improved bone formation.

The daily swab test collection problem

Digital Contact Tracing (DCT) has been proved to be an effective tool to counteract the new SARS-CoV-2 or Covid-19. Despite this widespread effort to adopt the DCT, less attention has been paid to the organisation of the health logistics system that should support the tracing activities. Actually, the DCT poses a challenge to the logistics of the local health system in terms of number of daily tests to be collected and evaluated, especially when the spreading of the virus is soaring. In this paper we introduce a new optimisation problem called the Daily Swab Test Collection (DSTC) problem, that is the daily problem of collecting swab tests at home in such a way to guarantee a timely testing to people notified by the app to be in contact with a positive case. The problem is formulated as a variant of the team orienteering problem. The contributions of this paper are the following: (i) the new optimisation problem DSTC that complements and improves the DCT approach proposed by Ferretti et al. (Science 10.1126/science.abb6936, 2020), (ii) the DSCT formulation as a variant of the TOP and a literature review highlighting that this variant can have useful application in healthcare management, (iii) new realistic benchmark instances for the DSTC based on the city of Turin, (iv) two new efficient and effective hybrid algorithms capable to deal with realistic instances, (v) the managerial insights of our approach with a special regard on the fairness of the solutions. The main finding is that it possible to optimise the underlying logistics system in such a way to guarantee a timely testing to people recognised by the DCT.

Robust coupling of angiogenesis and osteogenesis by VEGF-decorated matrices for bone regeneration

Rapid vascularization of clinical-size bone grafts is an unsolved challenge in regenerative medicine. Vascular endothelial growth factor-A (VEGF) is the master regulator of angiogenesis. Its over-expression by genetically modified human osteoprogenitors has been previously evaluated to drive vascularization in osteogenic grafts, but has been observed to cause paradoxical bone loss through excessive osteoclast recruitment. However, during bone development angiogenesis and osteogenesis are physiologically coupled by VEGF expression. Here we investigated whether the mode of VEGF delivery may be a key to recapitulate its physiological function. VEGF activity requires binding to the extracellular matrix, and heterogeneous levels of expression lead to localized microenvironments of excessive dose. Therefore we hypothesized that a homogeneous distribution of matrix-associated factor in the microenvironment may enable efficient coupling of angiogenesis and bone formation. This was achieved by decorating fibrin matrices with a cross-linkable engineered version of VEGF (TG-VEGF) that is released only by enzymatic cleavage by invading cells. In ectopic grafts, both TG-VEGF and VEGF-expressing progenitors similarly improved vascularization within the first week, but efficient bone formation was possible only in the factor-decorated matrices, whereas heterogenous, cell-based VEGF expression caused significant bone loss. In critical-size orthotopic calvaria defects, TG-VEGF effectively improved early vascular invasion, osteoprogenitor survival and differentiation, as well as bone repair compared to both controls and VEGF-expressing progenitors. In conclusion, homogenous distribution of matrix-associated VEGF protein preserves the physiological coupling of angiogenesis and osteogenesis, providing an attractive and clinically applicable strategy to engineer vascularized bone. STATEMENT OF SIGNIFICANCE: The therapeutic regeneration of vascularized bone is an unsolved challenge in regenerative medicine. Stimulation of blood vessel growth by over-expression of VEGF has been associated with paradoxical bone loss, whereas angiogenesis and osteogenesis are physiologically coupled by VEGF during development. Here we found that controlling the distribution of VEGF dose in an osteogenic graft is key to recapitulate its physiological function. In fact, homogeneous decoration of fibrin matrices with engineered VEGF could improve both vascularization and bone formation in orthotopic critical-size defects, dispensing with the need for combined osteogenic factor delivery. VEGF-decorated fibrin matrices provide a readily translatable platform for engineering a controlled microenvironment for bone regeneration.

Therapeutic arteriogenesis by factor-decorated fibrin matrices promotes wound healing in diabetic mice

Chronic wounds in type-2 diabetic patients present areas of severe local skin ischemia despite mostly normal blood flow in deeper large arteries. Therefore, restoration of blood perfusion requires the opening of arterial connections from the deep vessels to the superficial skin layer, that is, arteriogenesis. Arteriogenesis is regulated differently from microvascular angiogenesis and is optimally stimulated by high doses of Vascular Endothelial Growth Factor-A (VEGF) together with Platelet-Derived Growth Factor-BB (PDGF-BB). Here we found that fibrin hydrogels decorated with engineered versions of VEGF and PDGF-BB proteins, to ensure protection from degradation and controlled delivery, efficiently accelerated wound closure in diabetic and obese db/db mice, promoting robust microvascular growth and a marked increase in feeding arterioles. Notably, targeting the arteriogenic factors to the intact arterio-venous networks in the dermis around the wound was more effective than the routine treatment of the inflamed wound bed. This approach is readily translatable to a clinical setting.

Robust Angiogenesis and Arteriogenesis in the Skin of Diabetic Mice by Transient Delivery of Engineered VEGF and PDGF-BB Proteins in Fibrin Hydrogels

Non-healing ulcers are a serious complication of diabetes mellitus and a major unmet medical need. A major cause for the lack of healing is the impairment of spontaneous vascularization in the skin, despite mostly normal blood flow in deeper large vessels. Therefore, pro-angiogenic treatments are needed to increase therapeutic perfusion by recruiting new arterial connections (therapeutic arteriogenesis). Vascular endothelial growth factor (VEGF) is the master regulator of angiogenesis in physiology and disease, but exploitation of its therapeutic potential requires careful control of its dose distribution in tissue. Co-delivery of platelet derived growth factor-BB (PDGF-BB) has been shown to expand the therapeutic window of VEGF and also improve associated arteriogenesis. We used a highly controlled protein delivery system, based on a clinically applicable fibrin-based platform, to investigate the angiogenic and arteriogenic potential of engineered versions (TG-) of VEGF and PDGF-BB proteins in the skin of diabetic and obese db/db mice. Intradermal delivery of therapeutically relevant doses of TG-VEGF and TG-PDGF-BB induced robust growth of new microvascular networks with similar efficacy as in normal littermate control mice. Further, TG-PDGF-BB prevented the formation of aberrant vascular enlargements by high TG-VEGF levels. As fibrin was degraded after the first week, the induced angiogenesis mostly regressed by 4 weeks, but it promoted effective arteriogenesis in the dermal layer. Therefore, controlled co-delivery of TG-VEGF and TG-PDGF-BB recombinant proteins is effective to induce angiogenesis and arteriogenesis in diabetic mouse skin and should be further investigated to promote diabetic wound healing.

Suppression of Covid-19 outbreak among healthcare workers at the Treviso Regional Hospital, Italy and lessons for ophthalmologists

PURPOSE

To describe a strategy to reduce Covid-19 spread among healthcare workers and provide ophthalmologists with recommendations useful for a possible second wave of Covid-19 in Autumn.

METHODS

Epidemiological surveillance at the Cà Foncello Hospital (Veneto, Italy) since 24 February 2020 to 24 April 2020 when the municipality of Treviso was hit by the Covid-19 outbreak. The number of naso-pharigeal (NP) swabs performed was 7010.

RESULTS

The number of infected among healthcare workers was 209/ 3924 (5.32%): medical doctors: 28 cases / 498 (5.6%). None among ophthalmologists; specialized nurses: 86/1294 (6.4%) None in the ophthalmic unit; intermediate care technicians: 68/463 (14.7%). The 46% of the positive tested were asymptomatic. We share key suggested actions for the reorganization in ophthalmological services: be part of a global epidemiological local strategy of containment (Testing, Tracing, Treating); protect your department: Keep on screening patients by telephone interview before entering the hospital; promote continuous and appropriate use of PPE both for doctors and for patients; make any effort to obtain a continuous flow of patients in every line of the ophthalmic service; treat appropriately any single patient with vision threatening condition; avoid unnecessary or futile testings and examinations.

CONCLUSION

The Treviso model shows that it is possible and safe to keep on performing high risk hospital activities like ophthalmology, even in the epicenter of covid outbreak, if adequate actions are performed. We discuss about the value of NP swabs and serological tests as a strategy in case of a second wave of infections.

Fibrin hydrogels promote scar formation and prevent therapeutic angiogenesis in the heart

Therapeutic angiogenesis is the delivery of factors to promote vascular growth and holds promise for the treatment of ischemic heart conditions. Recombinant protein delivery to the myocardium by factor-decorated fibrin matrices is an attractive approach, thanks to the ability to precisely control both dose and duration of the treatment, the use of a clinically approved material like fibrin, and the avoidance of genetic modification. Here, we investigated the feasibility of inducing therapeutic angiogenesis in the rat myocardium by a state-of-the-art fibrin-based delivery platform that we previously optimized. Engineered versions of murine vascular endothelial growth factor A (VEGF₁₆₄ ) and platelet-derived growth factor BB (PDGF-BB) were fused with an octapeptide substrate of the transglutaminase coagulation factor fXIIIa (TG) to allow their covalent cross-linking into fibrin hydrogels and release by enzymatic cleavage. Hydrogels containing either 100 μg/mL TG-VEGF alone or in combination with 10 μg/mL TG-PDGF-BB or no factor were injected into rat myocardium. Surprisingly, vascular density was severely reduced in all conditions, both in and around the injection site, where large fibrotic scars were formed. Scar formation was not due to the presence of growth factors, adaptive immunity to human proteins, damage from injection, nor to mechanical trauma from the hydrogel stiffness or volume. Rather scar was induced directly by fibrin and persisted despite hydrogel degradation within 1 week. These results caution against the suitability of fibrin-based platforms for myocardial growth factor delivery, despite their efficacy in other tissues, like skeletal muscle. The underlying molecular mechanisms must be further investigated in order to identify rational targets to prevent this serious side effect.

VEGF Over-Expression by Engineered BMSC Accelerates Functional Perfusion, Improving Tissue Density and In-Growth in Clinical-Size Osteogenic Grafts

The first choice for reconstruction of clinical-size bone defects consists of autologous bone flaps, which often lack the required mechanical strength and cause significant donor-site morbidity. We have previously developed biological substitutes in a rabbit model by combining bone tissue engineering and flap pre-fabrication. However, spontaneous vascularization was insufficient to ensure progenitor survival in the core of the constructs. Here, we hypothesized that increased angiogenic stimulation within constructs by exogenous VEGF can significantly accelerate early vascularization and tissue in-growth. Bone marrow stromal cells from NZW rabbits (rBMSC) were transduced with a retroviral vector to express rabbit VEGF linked to a truncated version of rabbit CD4 as a cell-surface marker. Autologous cells were seeded in clinical-size 5.5 cm³ HA scaffolds wrapped in a panniculus carnosus flap to provide an ample vascular supply, and implanted ectopically. Constructs seeded with VEGF-expressing rBMSC showed significantly increased progenitor survivival, depth of tissue ingrowth and amount of mineralized tissue. Contrast-enhanced MRI after 1 week in vivo showed significantly improved tissue perfusion in the inner layer of the grafts compared to controls. Interestingly, grafts containing VEGF-expressing rBMSC displayed a hierarchically organized functional vascular tree, composed of dense capillary networks in the inner layers connected to large-caliber feeding vessels entering the constructs at the periphery. These data constitute proof of principle that providing sustained VEGF signaling, independently of cells experiencing hypoxia, is effective to drive rapid vascularization and increase early perfusion in clinical-size osteogenic grafts, leading to improved tissue formation deeper in the constructs.

Determinants, consequences and potential solutions to poor adherence to anti-osteoporosis treatment: results of an expert group meeting organized by the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO) and the International Osteoporosis Foundation (IOF)

Many patients at increased risk of fractures do not take their medication appropriately, resulting in a substantial decrease in the benefits of drug therapy. Improving medication adherence is urgently needed but remains laborious, given the numerous and multidimensional reasons for non-adherence, suggesting the need for measurement-guided, multifactorial and individualized solutions.

INTRODUCTION

Poor adherence to medications is a major challenge in the treatment of osteoporosis. This paper aimed to provide an overview of the consequences, determinants and potential solutions to poor adherence and persistence to osteoporosis medication.

METHODS

A working group was organized by the European Society on Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal diseases (ESCEO) to review consequences, determinants and potential solutions to adherence and to make recommendations for practice and further research. A systematic literature review and a face-to-face experts meeting were undertaken.

RESULTS

Medication non-adherence is associated with increased risk of fractures, leading to a substantial decrease in the clinical and economic benefits of drug therapy. Reasons for non-adherence are numerous and multidimensional for each patient, depending on the interplay of multiple factors, suggesting the need for multifactorial and individualized solutions. Few interventions have been shown to improve adherence or persistence to osteoporosis treatment. Promising actions include patient education with counselling, adherence monitoring with feedback and dose simplification including flexible dosing regimen. Recommendations for practice and further research were also provided. To adequately manage adherence, it is important to (1) understand the problem (initiation, implementation and/or persistence), (2) to measure adherence and (3) to identify the reason of non-adherence and fix it.

CONCLUSION

These recommendations are intended for clinicians to manage adherence of their patients and to researchers and policy makers to design, facilitate and appropriately use adherence interventions.

Runaway electron imaging spectrometry (REIS) system

A portable Runaway Electron Imaging and Spectrometry System (REIS) was developed in ENEA-Frascati to measure synchrotron radiation spectra from in-flight runaway electrons in tokamaks. The REIS is a wide-angle optical system collecting simultaneously visible and infrared emission spectra using an incoherent bundle of fibers, in a spectral range that spans from 500 nm to 2500 nm, and visible images using a CCD color microcamera at a rate of 25 frames/s. The REIS system is supervised and managed using a dedicated LabVIEW program to acquire data simultaneously from three spectrometers every 20 ms (configurable down to 10 ms). An overview of the REIS architecture and acquisition system and resulting experimental data obtained in FTU are presented and discussed in this paper.

The course of asthma during pregnancy in a recent, multicase-control study on respiratory health

Background

Over the years it has been widely stated that approximately one-third of asthmatic women experience worsening of the disease during pregnancy. However, the literature has not been reviewed systematically and the meta-analytic reviews include old studies. This study aimed to examine whether the prevalence of worsening asthma during pregnancy is still consistent with prior estimate or it has been reduced.

Methods

A detailed Clinical Questionnaire on respiratory symptoms, medical history, medication, use of services, occupation, social status, home environment and lifestyle was administered to random samples of the Italian population in the frame of the Gene Environment Interactions in Respiratory Diseases (GEIRD) study. Only clinical data belong to 2.606 subjects that completed the clinical stage of the GEIRD study, were used for the present study.

Results

Out of 1.351 women, 284 self-reported asthma and 92 of them had at least one pregnancy. When we considered the asthma course during pregnancy, we found that 16 women worsened, 31 remained unchanged, 25 improved. Seven women had not the same course in the different pregnancies and 13 did not know. The starting age of ICS use almost overlaps with that of asthma onset in women with worsening asthma during pregnancy (19 years ± 1.4), unlike the other women who started to use ICS much later (30.3 years ± 12). In addition, the worsening of asthma was more frequent in women with an older age of onset of asthma (18 years ± 9 vs 13 years ± 10). Among women who completed the ACT during the clinical interview, the 50% of women who experienced worsening asthma during pregnancy (6/12) had an ACT score below 20.

Conclusion

Asthma was observed to worsen during pregnancy in a percentage much lower to that generally reported in all the previous studies. There is still room in clinical practice to further reduce worsening of asthma during pregnancy by improving asthma control, with a more structured approach to asthma education and management prepregnancy.

Choosing wisely and the use of antibiotics in ophthalmic surgery: There is more than meets the eye

BACKGROUND:

One of the directions of modern ophthalmology is toward an odontoiatric model, and new settings of eye care are becoming the standard of care: one day surgery and also office-based therapies.

METHODS:

Retrospective analysis of three tertiary-care centers in Italy and analysis of the literature.

RESULTS:

We provide readers with state-of-the-art measures of prophylaxis in ophthalmic surgery.

DISCUSSION AND CONCLUSION:

Role of antibiotics is criticized in the light of stewardship antimicrobial paradigm.

It Takes Two to Tango: Coupling of Angiogenesis and Osteogenesis for Bone Regeneration

Bone regeneration is a complex process requiring highly orchestrated interactions between different cells and signals to form new mineralized tissue. Blood vessels serve as a structural template, around which bone development takes place, and also bring together the key elements for bone homeostasis into the osteogenic microenvironment, including minerals, growth factors and osteogenic progenitor cells. Vascular endothelial growth factor (VEGF) is the master regulator of vascular growth and it is required for effective coupling of angiogenesis and osteogenesis during both skeletal development and postnatal bone repair. Here, we will review the current state of knowledge on the molecular cross-talk between angiogenesis and osteogenesis. In particular, we will focus on the role of VEGF in coupling these two processes and how VEGF dose can control the outcome, addressing in particular: (1) the direct influence of VEGF on osteogenic differentiation of mesenchymal progenitors; (2) the angiocrine functions of endothelium to regulate osteoprogenitors; (3) the role of immune cells, e.g., myeloid cells and osteoclast precursors, recruited by VEGF to the osteogenic microenvironment. Finally, we will discuss emerging strategies, based on the current biological understanding, to ensure rapid vascularization and efficient bone formation in regenerative medicine.

Refining Coats' disease by ultra-widefield imaging and optical coherence tomography angiography

PURPOSE

The purpose of our study was to describe ultra-widefield (UWF) imaging and optical coherence tomography angiography (OCT-A) findings in affected and fellow eyes of patients with Coats' disease.

METHODS

Consecutive patients affected by Coats' disease were prospectively recruited at the Department of Ophthalmology, San Raffaele Hospital, Milan, Italy in this cross-sectional, observational study. Patients underwent UWF color fundus photographs, UWF green autofluorescence, UWF fluorescein angiography (FA), optical coherence tomography (OCT), with 3 × 3 mm and 6 × 6 mm OCT-A scans of the macula. Images were qualitatively evaluated by two independent operators for the presence of pathology.

RESULTS

Eleven patients affected by Coats' disease (eight males, mean age 17.1 ± 6.7 years). Nine and two patients had a clinical diagnosis of unilateral and bilateral disease, respectively. Five eyes had macular fibrosis. All clinically affected eyes exhibited retinal pathology at UWF imaging with the temporal sector most involved followed by the inferior, nasal, superior and macula. In all eyes with macular fibrosis, OCT-A revealed replacement of the foveal avascular zone with coarse vessels suggestive of vascularized fibrosis and flow void area in the choriocapillaris due to a masking effect; type 3 neovascularization was seen in 75% of cases. Seven out of nine clinically unaffected fellow eyes showed retinal pathology at UWF FA with the temporal quadrant most involved.

CONCLUSION

We demonstrated that Coats' disease is a highly asymmetric bilateral disease and that UWF imaging is able to identify more retinal pathology than standard fundus imaging, thus guiding proper retinal photocoagulation. OCT-A allowed easy identification of type 3 neovascularization in a proportion of patients with macular fibrosis.

Auditory cortex involvement in emotional learning and memory

Emotional memories represent the core of human and animal life and drive future choices and behaviors. Early research involving brain lesion studies in animals lead to the idea that the auditory cortex participates in emotional learning by processing the sensory features of auditory stimuli paired with emotional consequences and by transmitting this information to the amygdala. Nevertheless, electrophysiological and imaging studies revealed that, following emotional experiences, the auditory cortex undergoes learning-induced changes that are highly specific, associative and long lasting. These studies suggested that the role played by the auditory cortex goes beyond stimulus elaboration and transmission. Here, we discuss three major perspectives created by these data. In particular, we analyze the possible roles of the auditory cortex in emotional learning, we examine the recruitment of the auditory cortex during early and late memory trace encoding, and finally we consider the functional interplay between the auditory cortex and subcortical nuclei, such as the amygdala, that process affective information. We conclude that, starting from the early phase of memory encoding, the auditory cortex has a more prominent role in emotional learning, through its connections with subcortical nuclei, than is typically acknowledged.

Pulmonary involvement in patients with Marfan Syndrome

AIM

Pulmonary involvement is not generally considered a main feature of Marfan syndrome, an autosomal connective tissue disorder caused by mutations in fibrillin 1. Thanks to the substantial progress in treatments, life expectation of these patients has been dramatically improved determining changes in different organ systems. The number of patients with pulmonary pathology may be higher than expected. Objective of the study was to evaluate the pulmonary involvement in all the patients referring to the largest Italian center for Marfan syndrome, assessing clinical examination and lung function tests.

METHODS

Clinical history, spirometry, lung volumes and diffusing capacity have been assessed in 64 patients of our national referral center.

RESULTS

None of the patients reported chronic respiratory symptoms. Fourteen percent reported a previous pneumothorax and 3 blebs and 45% had moderate to severe rib cage abnormalities. Twenty-three percent had cardiothoracic surgery. Two of the 19 patients with chest TC performed at our hospital were diagnosed with emphysema and were both non smoker; 7 had subpleural apical blebs. Only 37% of patients had normal lung function; 19% showed a restrictive pattern and 44% an obstructive pattern or an isolated diffusion impairment or an isolated hyperinflation. All patients with pneumothorax showed an obstructive pattern and diffusion impairment.

CONCLUSION

In the absence of early respiratory symptoms, pulmonary abnormalities should be detected and monitored before they aggravate. Particular attention should be paid to prevent pneumothorax. Our results support the importance of lung volume determination to identify patients in which pulmonary parenchyma require a careful chest CT evaluation.

Twenty-five-gauge vitrectomy versus 23-gauge vitrectomy in the management of macular diseases: a comparative analysis through a Health Technology Assessment model

Small-gauge vitreoretinal techniques have been shown to be safe and effective in the management of a wide spectrum of vitreoretinal diseases. However, the costs of the new technologies may represent a critical issue for national health systems. The aim of the study is to plan a Health Technology Assessment (HTA) by performing a comparative analysis between the 23- and 25-gauge techniques in the management of macular diseases (epiretinal membranes, macular holes, vitreo-macular traction syndrome). In this prospective study, 45-80-year-old patients undergoing vitrectomy surgery for macular disease were enrolled at the Torino Eye Hospital. In the HTA model we assessed the safety, clinical effectiveness, and cost and financial evaluation of 23-gauge compared with 25-gauge vitrectomies. Fifty patients entered the study; 14 patients underwent 23-gauge vitrectomy and 36 underwent 25-gauge vitrectomy. There was no statistically significant difference in post-operative visual acuity at 1 year between the two groups. No cases of retinal detachment or endophtalmitis were registered at 1-year follow-up. The 23-gauge technique was slightly more expensive than the 25-gauge: the total surgical costs were EUR1217.70 versus EUR1164.84 (p = 0.351). We provide a financial comparison between new vitreoretinal procedures recently introduced in the market and reimbursed by the Italian National Health System and we also stimulate a critical debate about the expensive technocratic model of medicine.

What defines airflow obstruction in asthma?

Asthma guidelines from the Global Initiative for Asthma (GINA) and from the National Heart, Lung, and Blood Institute provide conflicting definitions of airflow obstruction, suggesting a fixed forced expiratory volume in 1 s (FEV(1))/forced vital capacity (FVC) cut-off point and the lower limit of normality (LLN), respectively. The LLN was recommended by the recent American Thoracic Society/European Respiratory Society guidelines on lung function testing. The problem in using fixed cut-off points is that they are set regardless of age and sex in an attempt to simplify diagnosis at the expense of misclassification. The sensitivity and specificity of fixed FEV(1)/FVC ratios of 0.70, 0.75 and 0.80 versus the LLN were evaluated in 815 subjects (aged 20-44 yrs) with a diagnosis of asthma within the framework of the European Community Respiratory Health Survey. In males, the 0.70 ratio showed 76.5% sensitivity and 100.0% specificity, the 0.75 ratio 100.0% sensitivity and 92.4% specificity, and the 0.80 ratio 100.0% sensitivity but 58.1% specificity. In females, the 0.70 ratio showed 57.3% sensitivity and 100.0% specificity, the 0.75 ratio 91.5% sensitivity and 95.9% specificity, and the 0.80 ratio 100.0% sensitivity but 72.9% specificity. The fixed cut-off points cause a lot of misidentification of airflow obstruction in young adults, with overestimation with the 0.80 ratio and underestimation with the 0.70 ratio. In conclusion, the GINA guidelines should change their criteria for defining airflow obstruction.

Comparison between generalized retinal arteriolar narrowing and left ventricular mass in young untreated hypertensive patients

PURPOSE

This study aims to examine the relationship between retinal arteriolar narrowing and left ventricular hypertrophy in hypertensive patients.

METHODS

A total of 30 patients with a recent history of hypertension (22 M, 8 F; 33 +/- 8; BMI 24,96 +/- 2.8;), consecutively referred to the Hypertension Unit by their family doctors, were studied. Generalized retinal arteriolar narrowing was measured by two ophthalmologists from computer-scanned images on retinal photographs, and summarized as arteriole-to-venule ratio (AVR). Left ventricular hypertrophy was evaluated by quantitative M-mode echocardiography.

RESULTS

All patients were stratified according to the 2003 European Society of Hypertension (ESH) guidelines: 20 subjects (66.7%) were affected by hypertension grade 1, and 10 (33.3%) were affected by hypertension grade 2. Retinal vessel diameters did not differ significantly by grade 1 vs grade 2 hypertension. Echocardiographic left ventricular hypertrophy was present in 10 (33%) patients. No significant correlation was shown between arteriole-to-venule ratio (AVR) and left ventricular mass. [Spearman r = 0.22; p = 0.23].

CONCLUSIONS

We suggest some explanations for the fact that we did not find any correlation between AVR and left ventricular mass. Further clinical studies are required for a greater understanding as to whether early microvascular changes relate with other clinical indicators of hypertensive organ damage.

Subfoveal choroidal neovascularization in a patient with hemicentral vein occlusion

The association between choroidal neovascularization (CNV) and retinal vein occlusive disease is uncommon. Before the introduction of anti-vascular endothelial growth factor (VEGF) drugs, photodynamic therapy (PDT) was used, with conflicting functional results. We report a case of a 69-year-old male patient who came to our attention for macular edema in hemiretinal vein occlusion. Fluorescein angiogram showed presence of venous collaterals, but the pattern of the edema was atypical; optical coherence tomography (OCT) and indocyanine green angiography (ICG) were used to confirm the diagnosis of CNV. A chorio-retinal shunt was demonstrated. The autofluorescence technique was used to predict the risk of CNV in the fellow eye. PDT was performed twice, but after the second cycle, patient developed choroidal ischemia and the visual outcomes were poor. The temporal course of CNV, the presence of a chorio-retinal shunt, and the autofluorescence pattern in the fellow eye let us to speculate that the CNV was related to the vascular occlusive process. We can speculate that the overexpression of VEGF induced by local ischemia and inflammation can make these patients more likely to have CNV. However, to our knowledge, there are no accurate estimates of the incidence of CNV in other retinal vascular diseases, such as diabetic retinopathy.

A histochemical approach to the evaluation of the in vivo cytotoxicity of the nitrobutadienes (1E,3E)-1,4-bis(1-naphthyl)-2,3-dinitro-1,3-butadiene and methyl (2Z,4E)-2-methylsulfanyl-5-(1-naphthyl)-4-nitro-2,4-pentadienoate in mice liver and kidney

Two new molecules (1E,3E)-1,4-bis(1-naphthyl)-2,3-dinitro-1,3-butadiene (1-Naph-DNB) and (2Z,4E)-2-methylsulfanyl-5-(1-naphthyl)-4-nitro-2,4-pentadienoate (1-Naph-NMCB) in previous studies showed interesting antiproliferative activity in vitro. Furthermore, toxicological tests and histological analysis provided promising results, in particular for 1-Naph-NMCB that displayed lower toxic activity both in terms of lethal effect and tissue damage of the main organs. Finally, studies of the antitumour activity in vivo confirmed the efficacy of both molecules, though with some differences in tumour selectivity and levels of activity. In this investigation the activities of some specific enzymes, acid phosphatase (AcPase), alkaline phosphatase (AlkPase), catalase (Cat), succinic dehydrogenase (SDH), glucose-6-phosphatase (G6Pase) and K+ p-nitrophenyl phosphatase (K+ pNPPase) were studied in the liver and kidney as histopathological biomarkers, to assess the effects of the two compounds in organs generally involved in the metabolism and excretion of different drugs. As oxidative stress may also develop as a consequence of the toxic effect of chemicals, reactive oxygen species (ROS) production was evaluated by a histochemical method. The results indicated that some enzyme activities and ROS expression changed in a dose-related manner. Nevertheless, neither in the liver nor in the kidney were dramatic toxic effects evident. By contrast, the variations of some enzyme activities (AlkPase, AcPase, Cat, K+ pNPPase) were interpreted as possible defensive mechanisms for tolerating high dosage of the compounds.

Detection and management of vascular hypertension

Classic hypertensive retinopathy has been well known since the first categorization of retinal vascular changes with the ophthalmoscope made by Keith-Wagener and Barker. Clinicians were interested in using a noninvasive tool to show that severity of vascular hypertension was predictive of mortality. Recently, a microvascular etiology has been suggested to play an important role in the pathogenesis of vascular hypertension. The retinal vasculature can potentially be used to evaluate the role of the microcirculation and to provide new insights into the vascular etiology of vascular hypertension. In this review, we have focused the attention on the role of retinal imaging in the work-up of hypertensive subjects.

Is early age-related macular degeneration associated with cerebral MRI changes? The Atherosclerosis Risk in Communities study

PURPOSE

To examine the relation of early age-related macular degeneration (AMD) with cerebral magnetic resonance imaging (MRI) changes.

DESIGN

Population-based, cross-sectional study.

METHODS

A sample of 1,684 persons ages 51 to 72 years with no history of stroke had cerebral MRI and retinal photography. MRI scans were graded for severity of white matter lesions (WML), sulcal widening (SW), and ventricular enlargement (VE). AMD was graded from retinal photographs.

RESULTS

After adjustment for age, gender, race, or center, early AMD (5.0% of participants) was not significantly associated with WML (odds ratio [OR] 1.0, 95% confidence intervals [CI], 0.6 to 1.6), SW (OR 0.6, 95% CI, 0.4 to 1.2), or VE (OR 1.0, 95% CI, 0.6 to 1.8).

CONCLUSIONS

These data showed no statistically significant association of early AMD with cerebral MRI changes, but the study was limited by a small number of cases with wide CIs. Further studies may clarify these associations.