Quantitative assessment of aqueous flare: the effect of age and pupillary dilation

OBJECTIVE: To assess the effect of age and pupillary dilation on aqueous flare. METHODS: In this study, 100 eyes of 100 patients ranging in ages from 23 to 84 years were examined. Anterior chamber flare was measured before and after pupillary dilation using the Kowa laser flare meter (FM-500). Predilation and postdilation flare counts were compared by paired t-test. Stepwise regression analysis was then used to determine the effect of demographic variables on pre- and postdilation flare as well as the difference between pre-and postdilation flare counts. RESULTS: The predilation and postdilation flare counts correlated with age (P < 0.0001 for both pre-and postdilation flare counts). Correlation coefficient between age and flare measurements was R2 = 0.58 predilation and 0.63 postdilation. Flare intensity significantly decreased after pupillary dilation (P < 0.001). CONCLUSIONS: Anterior chamber flare increases with age. It might be related to blood-aqueous barrier instability. Pupillary dilation significantly decreases flare counts suggesting that aqueous protein concentration is dependent on aqueous flow rates.     

Coronary reactivity to endothelin-1 during partial ischemia and reperfusion in anesthetized goats. Role of nitric oxide and prostanoids

To examine the coronary reactivity to endothelin-1 and its interaction with nitric oxide or prostanoids during partial coronary ischemia and reperfusion, left circumflex coronary artery flow was electromagnetically measured, and partial occlusion of this artery was induced for 60 min, followed by reperfusion in anesthetized goats (eight non-treated, six treated with N(w)-nitro-L-arginine methyl esther (L-NAME) and five treated with meclofenamate). During partial occlusion, coronary vascular conductance was reduced by 24-37% (P<0.01), and the coronary vasodilatation in response to acetylcholine (3-100 ng) and sodium nitroprusside (1-10 microg) was much decreased in every case; the vasoconstriction in response to endothelin-1 (1-10 microg) was depressed in non-treated animals, and this depression was reversed by L-NAME and was accentuated by meclofenamate. At 30 min of reperfusion coronary vascular conductance remained decreased by 22-27% (P<0.01), and the vasodilatation in response to acetylcholine (3-100 ng) and sodium nitroprusside (1-10 microg), as well as the vasoconstriction with endothelin-1 (1-10 microg), were as in the control and comparable in the three groups of animals. These results suggest: (a) that during ischemia, the coronary vasodilator reserve is greatly reduced, and the vasoconstriction with endothelin-1 is blunted, with preservation of the modulatory role of nitric oxide and involvement of vasoconstrictor prostanoids in this vasoconstriction, and (2) that during reperfusion, the coronary vasodilator reserve and the coronary reactivity to acetylcholine and endothelin-1 recover, but the modulatory role of nitric oxide in this reactivity may be attenuated.     

Ten contributions to the use of qualitative methodology in an audit of internal communication in primary care

Qualitative methodology, originally belonging to the Social Sciences domain, has progressively incorporated to Health Research to the scepticism of many and the admiration of others. Nowadays, validity and fiability of these qualitative techniques is still questioned by a great amount of health researchers and their use provokes doubt among reviewers and other members of the scientific community. This article presents as a fundamental measure for the validity of the qualitative methodology its precise use to approach determinate research objectives specific to them and, echoing the extra issue of the Health Services Research on December 1999 on this methodology, gathers the contribution of the use of these techniques from a complementary point of view, in a Internal Communication Audit conducted in the Primary Care Services of four Regional Health Systems: Area II of the INSALUD (National Health Institute), Basque Health System, Canary Health System and Andalusian Health System.     

Comparative potencies of nutraceuticals in chemically induced skin tumor prevention

Four nutraceuticals, sugar beet roots, cucumber fruits, New Zealand spinach leaves, and turmeric rhizomes, were evaluated for their comparative effectiveness against dimethylbenz[a]anthracene (DMBA)-initiated and croton oil-promoted skin tumors. Three different protocols were used. The most effective protocol (Protocol 2) is the topical application of the nutraceuticals 1 h before croton oil. There was a decrease in the percent skin tumor incidence, a decrease in multiplicity of skin tumors, and a later onset of skin tumors compared with the positive control for all the nutraceuticals tested, with turmeric being the most potent, as evidenced by 30% skin tumor incidence, 87.2% decrease in skin tumors, and a 5-wk delay in skin tumor formation compared with the positive control. Topical application of the nutraceuticals daily for 5 days before DMBA and 1 h before croton oil (Protocol 1) and immediately after croton oil (Protocol 3) did not have an additional protective effect against skin tumors compared with Protocol 2. Kruskal-Wallis analysis of variance by ranks showed that Protocol 2 is the most effective, with the treatment groups belonging to different populations at the 0.05 level of significance compared with alpha = 0.20 for Protocols 1 and 3. Turmeric is the most potent nutraceutical, because the average number of tumors formed after application of tumeric is statistically different from the positive control at alpha = 0.01.     

Consensual inflammation following ocular surgery

PURPOSE: To determine whether a consensual inflammatory response occurs following unilateral phacoemulsification or trabeculectomy in humans. METHODS: Sixty patients undergoing phacoemulsification or primary trabeculectomy were included in the study. Some patients were randomly assigned to have a shield placed on the non-operated eye during surgery. The Kowa laser flare meter (FM-500) and laser cell counter (LC-500) (Kowa Electronics and Optics, Tokyo, Japan) were used to assess the inflammatory response in both eyes. Measurements were taken preoperatively and on postoperative days 1, 7 and 28. The regression analysis with random model effect was used to identify factors which may affect the change of flare and cells in the non-operated eye after surgery. Correlation was evaluated between the inflammatory responses of the paired eyes. A P<0.05 was considered statistically significant for all analyses. RESULTS: The flare and cells in the non-operated eye showed a small, but significant, increase on day 1 (mean flare increased 2.68 photons/ms from preoperative level with P<0.001 and mean cells increased 2.49 cells/0.5 mm3 from preoperative level with P<0.0001). At day 7 the amount of inflammation was still elevated (mean flare increased 0.41 photons/ms from preoperative level with P<0.001 and mean cells increased 0.63 cells/0.5 mm3 from preoperative level with P<0.001). By day 28, the amount of inflammation in the nonoperated eyes returned to preoperative levels. CONCLUSIONS: Subclinical inflammation occurs in the non-operated eye following phacoemulsification and trabeculectomy. The etiology of this finding has yet to be elucidated.     

Incomplete regression of müllerian ducts in the androgen insensitivity syndrome

The biochemical and histological features of two related patients with the complete form of the androgen insensitivity syndrome (AIS) coexisting with incomplete regression of the Müllerian ducts are described. Both patients presented unilateral Müllerian derivatives (fallopian tube) identified by microscopic examination of surgically excised internal genital tissue. Biochemical studies performed in genital skin-derived fibroblasts from one of the affected subjects showed the existence of a specific and saturable 8.2 to 8.4 S cytosolic and 3.4 S nuclear androgen receptor exhibiting a Kd of 1.32 nmol/L. These mutant cells, however, clearly presented a significantly low maximal nuclear [3H]-5 alpha-dihydrotestosterone uptake (71.0 fmol/mg of deoxyribonucleic acid [DNA]; control strain, 284 fmol/mg DNA). Thus, an impaired uptake of the androgen receptor complex at the nuclear level was probably the cause of the complete absence of phenotypic expression of androgen action in this family. The overall findings are on line with the well-demonstrated genetic and molecular heterogeneity of the AIS.     

Involvement of Mrp2 in hepatic and intestinal disposition of dinitrophenyl-S-glutathione in partially hepatectomized rats.

The ability of the liver and small intestine for secretion of dinitrophenyl-S-glutathione (DNP-SG), a substrate for multidrug resistance-associated protein 2 (Mrp2), into bile and lumen, respectively, as well as expression of Mrp2 in both tissues, were assessed in 70-75% hepatectomized rats. An in vivo perfused intestinal model was used. A single i.v. dose of 30 micromol/kg b.w. of 1-chloro-2,4-dinitrobenzene (CDNB) was administered and its glutathione conjugate, DNP-SG, was determined by HPLC in bile and intestinal perfusate. One and seven days after hepatectomy, biliary excretion of DNP-SG was decreased by 90 and 50% with respect to shams, respectively, when expressed per mass unit. In contrast, intestinal excretion was increased by 63% or unchanged one and seven days post-hepatectomy, respectively. Tissue content of DNP-SG 5 min after CDNB administration was substantially decreased in liver and significantly increased in intestine, one day post-hepatectomy. Western and immunofluorescence studies revealed preserved levels and localization of Mrp2 in both tissues from hepatectomized animals, irrespective of the time analyzed. In spite of preserved expression of Mrp2, the higher availability of DNP-SG in intestinal cells, likely as a consequence of increased glutathione-S-transferase-mediated conjugation of CDNB, may explain the in vivo findings. Further experiments in isolated hepatocytes suggested that decreased synthesis of DNP-SG rather than altered canalicular transport is responsible for the substantial impairment in excretion of this compound into bile. Taken together, these results indicate that the intestine may partially compensate for liver DNP-SG disposition, particularly shortly after surgery, while liver capability is recovering.     

Genetic analysis of three genes causing isolated methylmalonic acidemia: identification of 21 novel allelic variants

Isolated methylmalonic aciduria (MMA) is an inborn error of metabolism due to the impaired isomerization of l-methylmalonyl-CoA to succinyl-CoA. This reaction is catalyzed by the mitochondrial protein methylmalonyl-CoA mutase (MCM, EC 5.4.99.2), an adenosylcobalamin-dependent enzyme. Four different forms of isolated MMA have been described: mut MMA associated with defects in the MCM apoenzyme, and phenotypically divided into two subtypes mut- and mut0 MMA, and three different defects involved in the synthesis of the active form of the cofactor adenosylcobalamin, termed cbl MMA, and classified into three different complementation groups cblA, cblB, and cblH associated with defects in the MMAA and MMAB genes and with an unidentified protein, respectively. In this work we describe the genetic analysis of 25 MMA patients, mainly from Spain. Using biochemical and cellular approaches our patients have been classified, identifying 13 mut MMA, 7 cblA, 2 cblB, and 3 noncblA, noncblB deficient patients. cDNA and genomic DNA sequence analysis of the MUT, MMAA, and MMAB genes have allowed us to identify 27 different changes, 21 novel ones. Among the missense mutations identified in the MUT gene only one, the c.970G>A (p.A324T) variant located in the substrate binding domain is likely a mut- mutation. The remaining missense mutations c.326A>G (p.Q109R), c.983T>C (p.L328P), c.1846C>T (p.R616C), and c.1850T>G (p.L617R) are probably mut0. In the MMAA patients analyzed, frameshift mutations are prevalent. We have explored the genotype-phenotype correlation for this clinically heterogeneous disease.     

Involvement of the dorsolateral funiculus in the descending spinal projections responsible for diffuse noxious inhibitory controls in the rat

Recordings were made from convergent neurons in the lumbar dorsal horn of the spinal cord of the rat. These neurons were activated by both innocuous and noxious mechanical stimuli applied to their excitatory receptive fields located on the extremity of the hindpaw. Transcutaneous application of suprathreshold 2-ms square-wave electrical stimuli to the center of the excitatory field, resulted in responses to C-fiber activation being observed. This type of response was inhibited by applying a noxious thermal conditioning stimulus on the muzzle. The immersion of the muzzle in a 52 degrees C waterbath resulted in a strong reduction of the response during the application of the noxious conditioning stimulus and this was followed by long lasting poststimulus effects. Such inhibitory processes have been termed diffuse noxious inhibitory controls (DNIC). The effects on these inhibitions of lesions including the dorsolateral funiculus (DLF) were investigated in acute experiments: tests were performed before and at least 30 min after the DLF lesion. A lesion including the DLF ipsilateral to the neuron under study completely abolished the inhibitory processes triggered from the muzzle. Concomitantly, a facilitation of C-fiber responses was observed. Nevertheless, DNIC was still impaired even using a juxtathreshold current to elicit a weak C-fiber response. To ascertain further the main, if not entire, participation of the ipsilateral DLF in the descending projections responsible for the heterotopic inhibitory processes, the effects of a lesion of the contralateral DLF were investigated. Neither the inhibitory processes nor the unconditioned C-fiber responses were altered by this procedure. Again, a second lesion including the ipsilateral DLF induced a blockade of DNIC. It is concluded that the descending projections involved in the triggering of DNIC are mainly, if not entirely, confined to the DLF ipsilateral to the neuron under study. The contralateral DLF did not appear to play a role in these processes.