Fishing-related ocular trauma

PURPOSE: To evaluate the characteristics of fishing-related ocular injuries. DESIGN: Retrospective observational analysis of a computerized databank. METHODS: The United States Eye Injury Registry was used to analyze 143 patients with fishing-related ocular injury. Epidemiologic and clinical information was evaluated including the age and gender of the subjects, classification of ocular trauma, surgical management, and final visual acuity. RESULTS: Of the 732 cases of sport-related ocular trauma, 143 (19.54%) occurred while fishing; of these, 79% were male patients who ranged in age from 6 to 68 years (mean, 37 years). Corneal laceration, globe rupture, and hyphema were the most common diagnoses at presentation and were caused by fishing hooks, lures, and weights. Thirty-five bystanders are included in the study. Thirty-eight percent of patients had visual acuity less than 20/50, and 21% had a visual acuity of less than 20/200. Open globe injuries portended a poor visual outcome compared with closed globe injuries. CONCLUSIONS: Fishing-related ocular injuries represent a large percent of sports-related trauma, often resulting in significant visual loss. Preventive measures such as the use of protective eyewear should be advised in this activity.     

Intracorneal injection of amphothericin B for recurrent fungal keratitis and endophthalmitis

Penetrating keratoplasty carries an infectious risk. Its requirement for topical corticosteroid therapy facilitates fungal growth with resulting keratitis. Although progression of fungal keratitis to intraocular infection is uncommon, endophthalmitis resulting from keratitis usually has a poor visual prognosis. Fungal infection under these circumstances remains a diagnostic and therapeutic challenge. We report a complicated case of recurrent fungal keratitis with endophthalmitis following a contaminated penetrating keratoplasty that ultimately was controlled with a new treatment modality. Intrastromal corneal injections combined with intravitreal injection of amphotericin B led to the eradication of the corneal fungal plaques and the intraocular infection. Intrastromal corneal injections of amphotericin B may offer a less invasive, in-office alternative to repeat penetrating keratoplasty.     

Mechanism of action of potato carboxypeptidase inhibitor (PCI) as an EGF blocker

The epidermal growth factor receptor (EGFR) signal transduction pathway plays a prominent role in the development of carcinomas, and is an interesting target for antitumoral therapy. We have previously described how potato carboxypeptidase inhibitor (PCI), a 39-amino acid protease inhibitor with a T-Knot motif, binds to EGFR receptor and inhibits the activation of receptor protein tyrosine kinase. In this paper it is shown that PCI interferes with EGFR activation through inhibition of receptor dimerization and receptor transphosphorylation induced by epidermal growth factor (EGF) and by transforming growth factor alpha (TGF-alpha). Moreover, PCI blocks the formation and activation of ErbB1/ErbB-2 heterodimers that have a prominent role in carcinoma development. As a result of these effects, PCI interferes in the EGFR signal transduction pathway by reversing the effects of EGF on the growth of two tumoral cell lines, A431 and MDA-MB-453, and promotes EGFR down-regulation. These results show that PCI acts as an EGF/TGF-alpha antagonist, which suggests its therapeutic potential in the treatment of carcinomas.     

Lack of benefit of pelvic radiation in prostate cancer patients with a high risk of positive pelvic lymph nodes treated with high-dose radiation

PURPOSE: The use of pelvic radiation for patients with a high risk of lymph node (LN) metastasis (>15%) remains controversial. We reviewed the data at three institutions treating patients with a combination of external-beam radiation therapy and high-dose-rate brachytherapy to address the prognostic implications of the use of the Roach formula and the benefit of pelvic treatment. METHODS AND MATERIALS: From 1986 to 2003, 1,491 patients were treated with external-beam radiation therapy and high-dose-rate brachytherapy. The Roach formula [2/3 prostate-specific antigen + (Gleason score -6) x 10] could be calculated for 1,357 patients. Group I consisted of patients having a risk of positive LN < or = 15% (n = 761), Group II had a risk >15% and < or = 30% (n = 422), and Group III had a risk of LN disease >30% (n = 174). A >15% risk of having positive LN was found in 596 patients and was used to determine the benefit of pelvic radiation. The pelvis was treated at two of the cancer centers (n = 312), whereas at the third center (n = 284) radiation therapy was delivered to the prostate and seminal vesicles alone. Average biologic effective dose was > or = 100 Gy (alphabeta = 1.2). Biochemical failure was as per the American Society for Therapeutic Radiology and Oncology definition. Statistics included the log-rank test as well as Cox univariate and multivariate analysis. RESULTS: For all 596 patients with a positive LN risk >15%, median follow-up was 4.3 years, with a mean of 4.8 years. For all cases, median follow-up was 4 years and mean follow-up was 4.4 years. Five-year results for the three groups based on their risk of positive LN were significantly different in terms of biochemical failure (p < 0.001), clinical control (p < 0.001), disease-free survival excluding biochemical failure (p < 0.001), cause-specific survival (p < 0.001), and overall survival (p < 0.001). For all patients with a risk of positive LN >15% (n = 596), Group II (>15-30% risk), or Group III (>30% risk), no benefit was seen in the 5-year rates of clinical failure, cause-specific survival, or overall survival with pelvic radiation. In the Cox multivariate analysis for cause-specific survival, Gleason score (p = 0.009, hazard ratio [HR] 3.1), T stage (p = 0.03, HR 1.8), and year of treatment (p = 0.05, HR 1.1) were significant. A log-rank test for cause-specific survival for all patients (n = 577) by the use of pelvic radiation was not significant (p = 0.99) accounting for high-dose-rate brachytherapy dose, neoadjuvant hormones, Gleason score, prostate-specific antigen, T stage, and year of treatment as covariates. CONCLUSIONS: The use of the Roach formula to stratify patients for clinical and biochemical outcomes is excellent. Pelvic radiation added to high prostate radiation doses did not show a clinical benefit for patients at a high risk of pelvic LN disease (>15%) selected using the Roach formula.     

Redox interactions of nitric oxide with dopamine and its derivatives

Nitric oxide (*NO) is a ubiquitous diffusible messenger in the central nervous system. *NO and derived nitrogen species may interact with catecholamines, thus, modifying not only its regulatory actions but also producing oxidants and free radicals that are likely to trigger toxic pathways in the nervous system. Oxidative pathways and chain oxidation reactions triggered by catecholamines may be broken by ascorbate and glutathione, of which there is ample supply in the brain. At the subcellular level, mitochondria and cytosolic dopamine storage vesicles are likely to provide site-specific settings for *NO and catecholamines interactions. Thus, a complex picture emerges in which the steady- state levels of the individual reactants, the rate constants of the reactions involved, the oxygen tension, and the compartmentalization of reactions determine the biological significance of the redox interactions between *NO and dopamine metabolism in the brain. The physiological relevance of *NO-driven chemical modifications of dopamine and its derivatives and the ensuing free radical production are discussed in connection with the neurodegeneration inherent in Parkinson's disease.     

Medicinal chemistry driven approaches toward novel and selective serotonin 5-HT6 receptor ligands

Based on a medicinal chemistry guided hypothetical pharmacophore model, novel series of indolyl sulfonamides have been designed and prepared as selective and high-affinity serotonin 5-HT(6) receptor ligands. Furthermore, based on a screening approach of a discovery library, a series of benzoxazinepiperidinyl sulfonamides were identified as selective 5-HT(6) ligands. Many of the compounds described in this paper possess excellent affinities, displaying pK(i) values greater than 8 (some even >9) and high selectivities against a wide range (>50) of other CNS relevant receptors. First, structure-affinity relationships of these ligands are discussed. In terms of functionality, high-affinity antagonists, as well as agonists and even partial agonists, were prepared. Compounds 19c and 19g represent the highest-affinity 5-HT(6) agonists ever reported in the literature. These valuable tool compounds should allow for the detailed study of the role of the 5-HT(6) receptor in relevant animal models of disorders such as cognition deficits, depression, anxiety, or obesity.     

Synthesis of new benzoxazinone derivatives as neuropeptide Y5 antagonists for the treatment of obesity

Screening of our internal chemical collection against the neuropeptide Y5 (NPY Y5) receptor allowed the identification of a benzoxazine derivative 5f as a hit that showed moderate affinity (IC(50) = 300 nM). With the aim of improving the in vitro potency, a series of 2-benzoxazinone derivatives have been synthesized and tested for NPY Y5 activity. Most of the compounds were found to be potent and selective NPY Y5 antagonists having nanomolar binding affinities for the NPY Y5 receptor and showing functional antagonism in the forskolin-induced cyclic AMP test. Prelimminary studies in order to understand the structure-activity relationship were undertaken. Selected compounds were further evaluated for in vivo efficacy, affording the lead compound 2-[4-(8-methyl-2-oxo-4H-benzo[d][1,3]oxazin-1-yl)piperidin-1-yl]-N-(9-oxo-9H-fluoren-3-yl)acetamide 5p, which displayed in vivo activity reducing food intake in rodents.     

Silibinin prevents cholestasis-associated retrieval of the bile salt export pump, Bsep, in isolated rat hepatocyte couplets: possible involvement of cAMP

Estradiol-17beta-d-glucuronide (E(2)17G) and taurolithocholate (TLC) induce acute cholestasis-associated with retrieval of the bile salt export pump (Bsep), which parallels with alteration in transport activity. cAMP stimulates the apically directed vesicular trafficking of transporters, partially preventing these alterations. The hepatoprotector, silymarin, which inhibits cAMP-phosphodiesterase, prevents the cholestasis induced in vivo by both estrogens and TLC. We aimed to assess the ability of silibinin (Sil), the silymarin active component, to prevent the retrieval of Bsep induced by TLC and E(2)17G, and the associated alteration in its transport function. The possible involvement of cAMP as a second messenger and the intracellular signalling pathways implicated were also evaluated. Functional studies were performed analysing the proportion of isolated rat hepatocyte couplets (IRHC) accumulating the fluorescent bile salt analogue, cholyl-lysylfluorescein (CLF), into their sealed canalicular vacuoles. Cellular localisation of Bsep was assessed by immunofluorescent staining. Intracellular levels of cAMP were measured by ELISA. Sil (2.5microM) elevated by 40+/-3% intracellular cAMP, and mimicked the ability of dibutyryl-cAMP (10microM) to prevent internalisation of Bsep and the TLC (2.5microM)- and E(2)17G (50microM)-induced impairment in the capacity of IRHC to accumulate CLF apically. Preventive effects of Sil and dibutyryl-cAMP were not abolished by the specific protein kinase A inhibitors, KT5720 and H89. Contrarily, the intracellular Ca(2+) chelator, BAPTA/AM, significantly blocked the protective effect of both compounds. We conclude that Sil prevented TLC- and E(2)17G-induced bile salt secretory failure, at least in part, by avoiding redistribution of Bsep, by a mechanism probably involving cAMP-induced cytosolic Ca(2+) elevations.     

Effect of androgen deprivation therapy in the thyroid function test of patients with prostate cancer

We have assessed the effect of androgen deprivation therapy (ADT) in the thyroid function test in prostate cancer patients. Serum levels of tri-iodothyronine (T3), thyroxine (T4), free thyroxine (FT4) and thyroid-stimulating hormone (TSH) were determined in a cross-sectional study that included 279 patients diagnosed with prostate cancer. A subset of 96 patients free of prostate-specific antigen relapse after radical prostatectomy became a control group and 183 patients under continuous ADT formed the study group. Sixty-four patients out of the study group were treated with luteinizing hormone-releasing hormone (LHRH) agonist and 119 with LHRH agonist plus bicalutamide. The average time of ADT was 42.5 months (3-218). Results were as follows. Mean T3 level was 122.7 ng/dl (72.6-213.0) in the control group and 123.8 ng/dl (64.4-228.2) in patients under ADT, p=0.472. Mean T4 level was 7.66 (1.81-4.30) and 7.66 microg/dl (3.60-13.30), respectively, p=0.884. Mean TSH level was 1.58 (0.44-11.70) and 1.81 mU/dl (0.15-6.58), respectively, p=0.007. Mean FT4 level was 1.24 (0.80-1.90) and 1.18 ng/dl (0.80-1.90), respectively, p=0.018. No statistically significant differences between the T3, T4, TSH and FT4 serum levels were detected according to the modality of ADT. The serum level of TSH was higher than 5 mU/l in six patients (2.1%); however, all cases had a normal FT4 serum level. This mild hypothyroidism was detected in two of the 96 patients of the control group (2.1%) and in four of the 183 under ADT (2.2%). Our data show that ADT seems to alter the thyroid function test. A statistically significant increase in TSH serum level and a decrease in FT4 serum level were detected in patients under ADT. However, only a mild hypothyroidism was detected in about 2% of the patients with prostate cancer, independently of ADT.