On Sensor Bias in Experimental Methods for Comparing Interest-Point, Saliency, and Recognition Algorithms.

Most current algorithm evaluation protocols use large image databases, but give little consideration to imaging characteristics used to create the data sets. This paper evaluates the effects of camera shutter speed and voltage gain under simultaneous changes in illumination and demonstrates significant differences in the sensitivities of popular vision algorithms under variable illumination, shutter speed, and gain. These results show that offline data sets used to evaluate vision algorithms typically suffer from a significant sensor specific bias which can make many of the experimental methodologies used to evaluate vision algorithms unable to provide results that generalize in less controlled environments. We show that for typical indoor scenes, the different saturation levels of the color filters are easily reached, leading to the occurrence of localized saturation which is not exclusively based on the scene radiance but on the spectral density of individual colors present in the scene. Even under constant illumination, foreshortening effects due to surface orientation can affect feature detection and saliency. Finally, we demonstrate that active and purposive control of the shutter speed and gain can lead to significantly more reliable feature detection under varying illumination and nonconstant viewpoints.

Primary effusion lymphoma in two HIV-negative patients successfully treated with pleurodesis as first-line therapy.

Primary effusion lymphoma (PEL) is a rare non-Hodgkin's lymphoma (NHL) mostly occurring in HIV-positive patients. It is characterized by the development of effusion in one or more body cavities, with no tumor masses and a positive human herpes virus-8 (HHV8) status. It has a poor survival profile and no optimal treatment is yet defined. We report two HIV-negative, HHV8-positive patients with PEL of the pleural cavity who achieved a durable remission after pleurodesis with bleomycin and no systemic therapy. We also perform a review of the relevant literature regarding the clinical data, treatment, and survival of PEL in HIV-negative patients.

Heart disease in thalassemia intermedia.

Thalassemia intermedia (TI) presents with a clinical phenotype ranging between the severe, transfusion-dependent TM and the asymptomatic carrier state. Cardiovascular complications represent the primary cause of mortality both in TM and in TI. Several factors have been reported to interfere in the pathophysiology of cardiovascular abnormalities in TI, including high output state, vascular abnormalities, endothelial dysfunction, elastic tissue disorders, hypercoagulability, valvular abnormalities and, to a less extent, iron overload. These mechanisms end up affecting both left and right heart, hence leading to ventricular remodeling and finally heart failure.

Assessment and treatment of cardiac iron overload in thalassemia.

Cardiac disease remains the major cause of death in thalassemia major and iron overload is involved in heart failure development. Cardiac iron load and heart injury are evaluated by different means, among which CMR measurements remain the best method for estimation. In cases of heart iron overload, chelation treatment should be appropriately tailored in terms of intensification.

Classification and characteristics of polymeric controlled-release systems.

The great importance of controlled release for the delivery of a variety of bioactive agents is evidenced by an increasing number of patents and commercial products that employ this technology. This article reviews the different controlled-release systems and their operating mechanisms.

Association of protein-losing enteropathy and cryoglobulinaemia.

We describe a case of protein-losing enteropathy in association with cryoglobulinaemia. No underlying disorder could be definitively diagnosed, but several clinical and laboratory findings suggested an immune mediated or autoimmune disorder. We propose that the mechanism of the protein-losing enteropathy in our case was immune complex formation, complement activation and endothelial damage.

Release of propranolol and diclofenac from low Mw DL-poly(lactic acid).

The controlled release of two drugs, i.e. the sodium salt of diclofenac and propranolol was studied, by using low molecular weight D,L-Poly(lactic acid) as a matrix. Tablets of the above polymer containing those drugs were immersed into buffers with various pH values and delivery was recorded as a function of time, via UV-spectroscopy. The results showed that the polymer is appropriate for such biomedical applications, as generally, it ensures complete drug delivery within 45-60 days, which is acceptable for most cases. On the other hand, the release rate depends on many parameters including the interactions among drug, matrix and the surrounding liquid, which adds complexity to the process and requires careful investigation for proper design of a controlled release system.

Fracture force, deflection at fracture, and toughness of repaired denture resin subjected to microwave polymerization or reinforced with wire or glass fiber.

STATEMENT OF PROBLEM: The ultimate goal of denture repair is to restore the denture's original strength and avoid further fracture. The best materials and methods for repair have not been conclusively determined. PURPOSE: This study investigated the fracture force, deflection at fracture, and toughness of a heat-polymerized denture base material repaired with heat-polymerized resin, autopolymerized resin alone, or autopolymerized resin with glass fiber or wire reinforcement. MATERIAL AND METHODS: Eight groups were evaluated: 6 with autopolymerized resin repairs, 1 with heat-polymerized resin repairs, and a control group of intact specimens. The 6 autopolymerized resin groups included 1 group with no reinforcement, 1 treated with microwave irradiation after polymerization, 2 with monolayer or multilayer glass fiber reinforcement, and 2 with round or braided wire reinforcement. Each group consisted of 12 specimens. The experimental specimens were cut, and a 3-mm butt joint gap was repaired as indicated by the group assignment. A 3-point bending test was used to determine the fracture force, deflection at fracture, and toughness of the specimens. The data were analyzed with 1-way analysis of variance and the Tukey post-hoc test (alpha=.05). RESULTS: The fracture force (28.4 to 73.4 N), deflection (1.6 to 3.8 mm), and toughness (0.02 to 0.13 J) values for all repaired groups were significantly lower than those for the control group (82.79 N, 4.4 mm, and 0.16 J, respectively), with one exception: the mean fracture force of specimens reinforced with round wire (102.9 N). Failure mode was always adhesive, meaning that fracture occurred between the denture base and repair resin. CONCLUSION: Among the repair treatments tested, the most effective was microwave-irradiated, autopolymerized resin reinforced with round wire or monolayer glass fiber ribbon.

Xanthan gum as a carrier for controlled release of drugs.

Systems based on xanthan gum matrix containing 1%, 2% and 5% salicylic acid were prepared and studied as controlled release devices. Swelling of the matrix in distilled water and buffer solutions showed that the ionic strength of the liquid has a strong effect on the sorptive properties of the matrix. From the release experiments, conducted in distilled water at 37 +/- 0.5 degrees C, it was found that the drug delivery process was accomplished within the first 10 hours after immersion and salicylic acid was always released via a non-Fickian transport. The phenomenon can be described by a release exponent (n) in the area of 0.77 independently of the initial concentration of salicylic acid in the xanthan matrix. These results can be interpreted taking into consideration the dimensional and physical changes of the polymeric matrix during swelling.

Swelling properties of various polymers used in controlled release systems.

The effect of powder packing and porosity of specimens on the swelling properties of polymeric materials was studied, in various swelling liquids, such as distilled water and 0.1 N hydrochloric acid solution. Capsules, tablets and films of hydroxypropyl methylcellulose, poly(ethylene oxide) and sodium alginate were prepared, and their weight uptake after immersion into the above solutions was recorded as a function of time, in order to assess the swelling process. Measurements of some characteristics of the as-received powders were also performed in an attempt to classify the specimens prepared according to their porosity. Within the experimental conditions of this work, it was shown that the porosity of polymeric specimens is a dominant factor that controls their swelling behaviour. Increased porosity leads to fast initial rates of weight uptake and high extent of equilibrium swelling. On the other hand, dissolution and possible degradation of polymers susceptible to acid hydrolysis results in some variations from the above mentioned behaviour. With respect to the application in controlled release systems, the overall delivery rate from a polymeric specimen is expected to be a function of both swelling and disintegration characteristics of a specimen, and therefore, the weight uptake can be considered a measure of the release only in the case of polymers with low water solubility and increased stability to hydrolysis.

Controlled release of salicylic acid from poly(D,L-Lactide).

Poly(D,L-Lactide) of high molecular weight (Mv) was prepared by ring-opening bulk polymerization of D,L-Lactide and characterized in terms of Mv, melting point and swelling behavior in buffer solution. Samples of the polymers with low and high Mv (2000 and 22 000 respectively) loaded with various amounts of salicylic acid (SA) were immersed in a buffer solution and the release of SA was recorded. The results obtained showed that swelling of the poly(D,L-Lactide) samples obeyed Fick's law, especially for those with high molecular weight, where biodegradation proceeds slowly. The release of SA seemed to follow a simplified relationship which is linear with time, at least for the early stages of delivery. The extent of linearity is dependent on the content of the acidic SA, which probably accelerates decomposition of the high molecular weight products.

Multilocalized pyomyositis in a previously healthy subject.

A case of pyomyositis is presented. This case is unique in the literature as at least 29 abscesses were detected, affecting the vast majority of big muscle groups. We outline the origin of this disease entity which selectively affects striated muscles. We also discuss its natural history and management strategy.

Swelling properties of various polymers used in controlled release systems.

The effect of powder packing and porosity of specimens on the swelling properties of polymeric materials was studied, in various swelling liquids, such as distilled water and 0.1 N hydrochloric acid solution. Capsules, tablets and films of hydroxypropyl methylcellulose, poly(ethylene oxide) and sodium alginate were prepared and their weight uptake after immersion into the above solutions was recorded as a function of time, in order to assess the swelling process. Measurements of some characteristics of the as received powders were also performed as an attempt to classify the specimens prepared according to their porosity. Within the experimental conditions of this work, it was shown that the porosity of polymeric specimens is a dominant factor that controls their swelling behaviour. Increased porosity leads to fast initial rates of weight uptake and high extent of equilibrium swelling. On the other hand, dissolution and possible degradation of polymers susceptible to acid hydrolysis, results in some variations from the above-mentioned behaviour. With respect to the application in controlled release systems, the overall delivery rate from a polymeric specimen is expected to be a function of both swelling and disintegration characteristics of a specimen and, therefore, the weight uptake can be considered a measure of the release only in the case of polymers with low water solubility and increased stability to hydrolysis.

Polymers for use in controlled release systems: the effect of surfactants on their swelling properties.

The effect of an ampholytic surfactant on the swelling properties of polymeric materials was studied, using various swelling liquids. Tablets were prepared consisting of hydroxypropyl methylcellulose, poly(oxyethylene) and sodium alginate. Tego betain was the non-ionic surfactant used as an additive in a series of samples made of the above polymers. Those tablets were immersed in distilled water, phosphate buffer and 0.1 N HCl, and their weight uptake was recorded as a function of time, in order to assess the swelling process. Measurements of the contact angle of the above systems were also carried out for estimating their wetting properties. The results of this study showed a selectivity among polymers, surfactant and surrounding liquid. Clearly, an enhancement of the swelling capacity of hydroxypropyl methylcellulose tablets due to the surfactant was recorded. An unclear effect was observed in the case of poly(oxyethylene), whereas for sodium alginate, the dominant factor is its water solubility that controls swelling behaviour.

Treatment of experimental osteomyelitis caused by methicillin-resistant Staphylococcus aureus with a biodegradable system of lactic acid polymer releasing pefloxacin.

A novel biodegradable system of D-,L-dilactide delivering pefloxacin was implanted in 104 rabbits with experimental osteomyelitis caused by methicillin-resistant Staphylococcus aureus (MRSA), 26 serving as controls. Animals were killed on each third day and viable bacterial counts and levels of pefloxacin in bone tissue were determined. A 99. 9% decrease in viable count of bacteria was achieved by day 12 and complete bacterial eradication on day 33. Pefloxacin was released gradually, reaching its peak on day 15 at levels 100 times the MIC of pefloxacin for MRSA. The biodegradable system described may have a future role in the therapeutic approach to osteomyelitis.

Physical properties of a silicone prosthetic elastomer stored in simulated skin secretions.

STATEMENT OF PROBLEM: Facial prostheses worn over an extended time are exposed to various environmental factors, including sebaceous oils (sebum) and perspiration. PURPOSE: This study investigated the physical properties of tensile strength and modulus, elongation, tear strength, hardness, weight, and color change, of a silicone facial elastomer after immersion for 6 months in simulated sebum and perspiration at 37 degrees C. MATERIAL AND METHODS: Specimens made of Episil silicone elastomer were immersed in simulated alkaline or acidic perspiration as well as in sebum. Tensile and tear tests were conducted according to ISO specifications no. 37 and 39, respectively, in a Monsanto testing machine. Shore A hardness measurements were run according to ASTM D 2240. Weight changes were followed at 5, 15, 30, and 180 days, and color changes were determined in the CIE LAB system using a tristimulus colorimeter. RESULTS: An improvement of mechanical properties for specimens immersed in acidic perspiration was attributed to facilitation of the propagation of cross-linking reaction during aging of the silicone samples. Some weight increase was observed for the specimens immersed into the aqueous solution, whereas for those immersed in sebum, weight loss was recorded, probably because of extraction of some compounds. In this latter case, the color change was lower than that corresponding to simulated perspiration. CONCLUSION: The silicone specimens aged for a period, which simulates 1.5 years of clinical service, showed minimal changes with respect to the properties studied.

Controlled release systems based on poly(lactic acid). An in vitro and in vivo study.

A new biodegradable delivery system based on poly(lactic acid) has been formulated, with potential applications in sustained antibiotic release against bone infection. The in vitro release of a new quinolone (pefloxacin) from low molecular weight poly(D,L-lactic acid) Mw = 2 x 10(3) lasted for 56 d whereas the in vivo delivery lasted 33 d. In both cases, the release rate is controlled by the drug diffusion and the polymer degradation, which seems to be the predominant factor. For the release experiments, discs were prepared from poly (D,L-lactide) Mw = 2 x 10(4) with drug loadings of 2% and 10% w/w. It was concluded that pefloxacin concentration remains higher than the Minimum Inhibitory Concentration (MIC) against the major causative bacteria of bone infection. The results indicate that the two different types of poly(lactic acid) can be used effectively in an implantable antibiotic release system.