ABCD: A new classification for keratoconus

Recent advances in the diagnosis and treatment of ectatic corneal disease have mandated a more modern staging system. The new Belin ABCD keratoconus staging system incorporates anterior and posterior curvature centered on the thinnest point of the cornea, thinnest pachymetry values and distance visual acuity in grades from 0-4. By including posterior curvature and thickness measurements based on the thinnest point, as opposed to apical, the new staging system better reflects anatomical changes seen in keratoconus and other ectatic diseases.     

Study of tear film optics and its impact on quality of vision

Purpose:To evaluate the relation of the tear film on the quality of vision comparing parameters in normal patients to those having dry eye disease.Methods:50 normal and 50 eyes with dry eye disease (DED) were included in the study. Patients were screened for dry eye with Schirmer''s test, tear break up time, ocular surface staining, and assessment of meibomian gland disease. Their quality of vision was assessed using the Optical quality analysis system (OQAS). The results of dry eye evaluation were correlated with the parameters on the OQAS especially the mean objective scatter index (OSI).Results:Patients with dry eye and unstable tear film were found to have a significantly worse quality of vision and optical scatter (P < 0.05). They were also noted to have fluctuation of vision between blinks.Conclusion:Tear film optics can have an important bearing on the quality of vision and quality of life. A detailed assessment preoperatively will help improve surgical outcomes and patient satisfaction.     

Preclinical pharmacokinetics and distribution to tissue of AG1343, an inhibitor of human immunodeficiency virus type 1 protease.

AG1343, a potent inhibitor of human immunodeficiency virus type 1 (HIV-1) protease (Ki = 2 nM), was designed by protein structure-based drug design techniques. AG1343 has potent antiviral activity (95% effective dose = 0.04 microgram/ml) against a number of HIV-1 strains in acute and chronic models of infection. As part of its preclinical development, the oral bioavailability of AG1343 in rats, dogs, monkeys, and marmosets was determined and its tissue distribution in rats was evaluated. There were no major interspecies differences in AG1343 pharmacokinetics. Following intravenous administration, the elimination half-life of AG1343 ranged from 1 to 1.4 hr. The total volume of distribution (2 to 7 liters/kg) exceeded the volume of total body water, indicating extensive tissue distribution. Systemic clearance of AG1343 (1 to 4 liters/kg) in the different species corresponded to hepatic blood flow, suggesting possible hepatic involvement in the elimination of AG1343. Following oral administration, peak levels in plasma ranged from 0.34 microgram/ml after treatment with 10 mg/kg of body weight in the dog to 1.7 micrograms/ml after dosing with 50 mg/kg in the rat. Because of the slow absorption of AG1343, plasma concentrations of AG1343 exceeding that required for 95% inhibition of HIV-1 replication were maintained for up to 7 h after a single oral dose in all species evaluated. Average oral bioavailability of AG1343 ranged from 17% in the marmoset to 47% in the dog. Studies of distribution to tissue in the rat after oral administration of 14C-AG1343 established extensive distribution with concentrations in most tissues exceeding that found in plasma. Of particular significance were high levels of AG1343 equivalent in mesenteric lymph nodes (32.05 micrograms/g) and spleen tissue (9.33 micrograms/g). The major excretory route for AG1343 was via feces, with 100% of the dose recovered by 48 h. Results from these studies demonstrate that AG1343 is orally bioavailable and that levels in plasma in the therapeutic range are achievable and are maintained for prolonged periods in the animal models tested. On the basis of these and other findings, AG1343 was developed for further testing in human subjects.     

Effect of foot deformity on conventional mechanical axis deviation and ground mechanical axis deviation during single leg stance and two leg stance in genu varum

We assessed the effect of foot deformity on the loading axis of lower limbs in 33 patients with genu varum (25 bilateral and eigth unilateral) caused by varying etiologies including achondroplasia, cerebral palsy, prior trauma, rickets, metaphyseal chondrodysplasia and primary osteoarthritis using single leg stance and both leg stance radiographs. Deviation at the knee from the hip ankle line (conventional) and hip foot line (centre of hip to centre of heel) was calculated. A comparison was made between single leg stance and two leg stance for tibiocalcaneal angle, mechanical axis angle, knee and ankle joint line convergence angle, conventional mechanical axis deviation (MADC) and ground mechanical axis deviation (MADG). In addition comparisons were also made among three groups formed depending on the tibiocalcaneal angle and MADC–MADG difference for all the above measurements.

Mechanical axis deviation (calculated using the two methods) varied with the talocalcaneal angle and single leg stance. Patients with a fixed subtalar varus and with severe genu varum, where the normal compensatory subtalar eversion could not compensate showed that conventional mechanical axis deviation was significantly higher by 3.4 ± 2.4 mm and ground mechanical axis deviation degrees was significantly higher by 3.8 ± 3.2 mm in single leg stance when compared to two leg stance (p < .0001).

Foot deformity should be included during preoperative evaluation and planning for knee deformity correction.     

Barium titanate microparticles as potential carrier platform for lanthanide radionuclides for their use in the treatment of arthritis

Since the inception of radiation synovectomy, a host of radioactive colloids and microparticles incorporating suitable therapeutic radionuclides have been proposed for the treatment of arthritis. The present article reports the synthesis and evaluation of barium titanate microparticles as an innovative and effective carrier platform for lanthanide radionuclides in the preparation of therapeutic agents for treatment of arthritis. The material was synthesized by mechanochemical route and characterized by X‐ray diffraction, scanning electron microscopy, surface area, and particle size distribution analyses. Loading of lanthanide radionuclides (¹⁶⁶Ho, ¹⁵³Sm, ¹⁷⁷Lu, and ¹⁶⁹Er) on the microparticles was achieved in high yield (> 95%) resulting in the formulation of loaded particulates with excellent radiochemical purities (> 99%). Radiolanthanide‐loaded microparticles exhibited excellent in vitro stability in human serum. In vitro diethylene triamine pentaacetic acid challenge study indicated fairly strong chemical association of lanthanides with barium titanate microparticles. Long‐term biodistribution studies carried out after administration of ¹⁷⁷Lu‐loaded microparticles into one of the knee joints of normal Wistar rats revealed near‐complete retention of the formulation (> 96% of the administered radioactivity) within the joint cavity even 14 days post‐administration. The excellent localization of the loaded microparticles was further confirmed by sequential whole‐body radio‐luminescence imaging studies carried out using ¹⁶⁶Ho‐loaded microparticles.     

Methamphetamine use and oral health-related quality of life

Purpose

Methamphetamine (MA) is associated with adverse health effects, including the rampant tooth decay condition called “Meth Mouth.” However, the impact of MA use on oral health-related quality of life (OHRQOL) is unknown. This study assessed the relationship between MA use and self-reported OHRQOL.

Methods

This cross-sectional study uses information from 545 MA-using participants recruited from Los Angeles County, California. Dental examinations were performed by three calibrated dentists using National Health and Nutrition Examination Survey (NHANES) protocols. Data on socio-demographic, behavioral, and drug-use history were recorded using questionnaires. Participants were categorized as ‘light’ or ‘moderate/heavy’ users based on reported frequency of MA use in the past 30 days. Route of MA administration was categorized as ‘smoking’ or ‘other.’ Self-reported OHRQOL was based on the Oral Health Impact Profile scale.

Results

Majority of the participants were male (80.9%). Median age was 45.0 years (IQR-13.0). Median number of days of MA use was 10.0 (IQR-12.0). Smoking was the preferred route of MA use (70.2%). Root caries in ≥?3 teeth were reported in 78% of MA users. More than half of the participants reported having painful aching in mouth, avoidance of particular food items, feeling embarrassed, and discomfort while eating in the last 12 months. In unadjusted logistic models, moderate/heavy MA users were more likely to report an affected sense of taste [OR?=?1.58, 95% CI (1.10–2.27)] and avoidance of particular foods [OR?=?1.45, 95% CI (1.02–2.01)] than light users. Among individuals preferring other MA administration routes, moderate/heavy MA users were 3.09 times as likely to report an affected sense of taste than light users [OR?=?3.09, 95% CI (1.52?6.27)].

Conclusion

Oral health and OHRQOL appear to be worse among Methamphetamine users than in the US general population.

     

Single stage craniofacial reconstruction for fronto-nasal encephalocele and hypertelorism in an adult

The fronto-nasal type of fronto-ethmoidal encephalocele is one of the more common subtype of anterior encephaloceles. We discuss different aspects and difficulties in the management of fronto-nasal encephalocele in a 30-year-old woman. Fronto-nasal encephaloceles present a difficult scenario in adults, mainly due to large gliotic herniating brain tissue, large bony and dural defect, increase in the size of paranasal sinuses, and scars from previous surgeries. However, all difficulties can be overcome after applying the principles of craniofacial reconstructions, i.e. correction of bone defect with autologus split calvarial graft, dural closure with autologous pericranial graft and correction of hypertelorism.     

Current role of thalidomide in HIV-positive patients with recurrent aphthous ulcerations

Among patients with HIV/AIDS, mucosal lesions of unknown etiology such as recurrent aphthous ulcerations (RAUs) often are unresponsive to standard therapies, resulting in substantial morbidity. The literature regarding RAUs suggests that the inflammatory response contributes to its pathogenesis; however, the role of cytokines in this mucosal immune response remains largely unknown. Thalidomide first was marketed as a sedative in the 1950s and withdrawn from the market in 1961 following reports of teratogenicity. Later, it was used as an investigational agent for the treatment of Hansen's disease, Kaposi's sarcoma, myelofibrosis, RAUs, and wasting associated with HIV. Thalidomide's mechanism of action in RAUs still is not understood completely, but it appears to be mediated by inhibition of the pro-inflammatory cytokine tumor necrosis factor alpha (TNF-alpha). This article discusses the current status of thalidomide for treating RAUs in HIV-positive patients. Suggestions regarding the safe and effective prescribing of thalidomide have been included so that dental professionals will be able to treat these patients safely.