The diagnostic value of intraocular fluid analysis by polymerase chain reaction in Thai patients with uveitis

Uveitis is a major cause of severe visual impairment throughout the world and can be initiated by various infectious and non-infectious causes. Early recognition of specific infections is important as the treatment with antimicrobial agents might stop the progression or even cure the eye disease. To determine the infectious causes of uveitis in Thailand, intraocular fluid samples of 100 HIV-negative patients and 47 HIV-positive patients with uveitis were examined using real-time PCR analysis for herpes simplex virus, varicella zoster virus, cytomegalovirus and Toxoplasma gondii. Positive PCR results were found in 33/100 (33%) HIV-negative patients and in 33/47 (70%) HIV-positive patients with uveitis. In Thailand, cytomegalovirus was identified as the most frequent cause of infectious uveitis in both HIV-negative and HIV-positive patients (49 and 91%, respectively). PCR analysis of intraocular samples in uveitis was a valuable diagnostic assay. The pattern of uveitis observed in the Far East differs from that found in the West.     

Electrospun Gelatin Fiber Mats Mixed With C.carandas Extract and its Enhanced Stability and Bioactivity

Crude C. carandas fruits ethanol extract (CCE) constituents important bioactive compounds such as phenolics, flavonoids, and vitamin C. Its biological activities include anti-inflammatory, antioxidant, antibacterial, etc. The present work was carried out to study the optimal conditions for fabricating electrospun gelatin fiber mats (GFM) loaded with CCE (CCE-GFM) and to evaluate the release capacity and stability of these bioactive compounds loaded into GFM. The optimal conditions for electrospinning GFM were the electrospinning 30% (w/v) gelatin solution prepared in 25% (v/v) ethanol solution containing 30% (v/v) acetic acid, under the fixed electrostatic field strength of 20 kV and at a distance between noodle tip and ground of 15 cm. The feed rate of an electrospinning solution was 1.5 mL/h. The electrospun gelatin fibers were smooth and continuous under the optimized electrospinning conditions, with an average diameter of 235.69 ± 10.45 nm. Additionally, at the loading of 15% (w/w) CCE in GFM, CCE-GFM exhibited the highest DPPH radical scavenging activity with 88.22 ± 2.62% and the highest tyrosinase inhibitory activity with 38.17 ± 1.86%. Compared with free CCE, CCE-GFM was more thermally stable upon the heating and cooling cycle testing. CCE-GFM had the percent reductions in total contents of phenolics, flavonoids and vitamin C togethering with the percent reductions of DPPH scavenging and anti-tyrosinase activities slower than pure CCE had. Furthermore, the drug release efficiency from CCE-GFM of 15% (w/w) CCE loading that was tested using modified Franz diffusion cell in an acetate buffer solution of pH 5.5 was 30%. CCE-GFM has shown the potential to utilize a facial mask sheet containing CCE valuable in high antioxidant activity for cosmetic applications.     

Role of impression cytology in diagnosis of ocular surface neoplasia

PURPOSE: To compare the accuracy of impression cytology in the diagnosis of ocular surface neoplasia with tissue histology. METHODS: We reviewed the histories of patients diagnosed with ocular surface neoplasia at the Chiang Mai University Hospital. All patients underwent both impression cytology and tissue biopsy. We compared the results of both methods. RESULTS: There were 55 patients (33 men and 22 women), with an age range of 12-99 years (mean, 51 years). Twenty patients had lesions in the right eye and 35 had them in the left eye. The most common histologic report was conjunctival-corneal intraepithelial neoplasia (38.2%), followed by squamous cell carcinoma (34.5%), nonneoplastic changes of squamous epithelia (10.9%), squamous papilloma (7.3%), conjunctival nevi (7.3%), and malignant melanoma (1.8%). Compared with histologic findings, the positive and negative predictive accuracy of impression cytology was 97.4% and 52.9%, respectively. For squamous neoplasms, squamous cell carcinoma had the highest correlation with histology. The presence of dysplastic cells suggested malignancy. CONCLUSIONS: This study shows that impression cytology might have a promising role in diagnosing ocular surface neoplasia for its high positive predictive accuracy compared with tissue histology. However, a fair negative predictive accuracy indicates that impression cytology is a valuable screening technique, but it is not a "gold standard."     

Isomorphic activation of astrocytes in the somatosensory thalamus.

Structural recovery in the rat somatosensory thalamus after the loss of one of its major inputs provided a model for studying the changes in astrocytes associated with reactive synaptogenesis. The temporal separation of the initiation of Wallerian degeneration and reactive synaptogenesis permitted astrocytic changes to be correlated either with the removal of degeneration, early in the recovery sequence, or with synaptogenesis, later in recovery. Over a period of post-lesion times ranging from 3 days to 13.5 months, GFAP-positive astrocytic fibers were quantified and the population density of S-100-positive astrocytic cell bodies was determined in the ventral posterolateral nucleus (VPL). The relative area of astrocytic cell bodies was measured at an early peak of the increased GFAP immunoreactivity (4-5 days post-lesion). The normal side of VPL (c-VPL) was compared to the deafferented side of VPL (d-VPL) and the ratio d-VPL/c-VPL was determined. Astrocytes in d-VPL underwent a minimal isomorphic activation with little or no hypertrophy or proliferation but with a large increase in GFAP immunoreactivity. Prior to the initiation of synaptogenesis, there was a decrease both in GFAP immunoreactivity and in the population density of VPL astrocytes. The decreases in the recovery curves suggested that a suppression of the influence of astrocytes may have been important for sprouting and/or synaptogenesis. In other systems, where synaptogenesis was initiated early in the recovery sequence, the suppression of astrocytes that was related to synaptogenesis may have been masked by astrocytic changes related to the removal of degeneration.