Phacoemulsification for visual refraction on the clear lens. Apropos of 33 severely myopic eyes

PURPOSE: To evaluate visual benefit, predictability and complications after clear lens phakoemulsification and posterior chamber implantation in highly myopic eyes. METHODS: Thirty-three highly myopic eyes were reviewed at a mean postoperative follow-up of 27 months. The mean age of the 19 patients was 31.04 +/- 5.51 years. The mean preoperative spherical equivalent was -19.50 +/- 7.0 D (-12 to -40 D). Preoperative best spectacle corrected visual acuity was compared with the last postoperative one. Postoperative spherical equivalent was compared with the desired value. All complications were reviewed. RESULTS: A mean visual benefit of 0.24 +/- 0.18 (decimal notation) was noted (p < 0.05). The mean postoperative spherical equivalent (-2.57 +/- 1.84 D) was not significantly different from the mean previous value (p = 0.75). Retinal detachment arose in the two eyes of the same patient (incidence of 6.1%). BSCVA decreased slightly in only one of the two eyes (0.1). The incidence of Nd-YAG capsulotomy was 30%. CONCLUSION: Clear lens phakoemulsification is an effective and predictable method for the correction of high myopia. Retinal detachment is the major complication of this technique, even if a severe decrease of the visual acuity is not usual.     

Chiral separation of amines by high-performance liquid chromatography after tagging with 4-(N,N-dimethylaminosulphonyl)-7-(2-chloroformylpyrrolidin-1-yl)- 2,1,3-benzoxadiazole

Chiral tagging reagents, 4-(N,N-dimethylaminosulphonyl)-7-(2-chloroformylpyrrolidin-1 -yl)-2,1,3- benzoxadiazole (R(+)-DBD-Pro-COCl and S(-)-DBD-Pro-COCl), react with mirror image enantiomers of amines to produce corresponding diastereomers in the presence of pyridine as a catalyst. The maximal excitation and emission wavelengths of the resulting diastereomers were ca. 450 nm and 560 nm, respectively. The diastereomers derived from some aliphatic amines were resolved by a reversed-phase chromatography with water-acetonitrile or normal-phase chromatography with n-hexane-ethyl acetate as the eluent. The reactivities of both enantiomers of DBD-Pro-COCl to chiral amines were almost comparable, whereas a slight difference of fluorescence intensity was observed with S(-)-DBD-Pro-COCl. When (S-)-DBD-Pro-COCl was used as the derivatization reagent, amines corresponding to S-configuration were eluted faster than R-configuration. The opposite elution order was obtained with the use of R(+)-DBD-Pro-COCl, instead of S(-)-DBD-Pro-COCl. The Rs values obtained from 1-cyclohexylethylamine (CEA) having aliphatic ring structure was larger than those of amines (1-(1-naphthyl)ethylamine (NEA) and 1-phenylethylamine (PEA)) having aromatic ring structures.     

High- versus low-dose ACE inhibition in chronic heart failure: a double-blind, placebo-controlled study of imidapril

OBJECTIVES: To determine dose-related clinical and neurohumoral effects of angiotensin-converting enzyme (ACE) inhibitors in patients with chronic heart failure (CHF), we conducted a double-blind, placebo-controlled, randomized study of three doses (2.5 mg, 5 mg and 10 mg) of the long-acting ACE inhibitor imidapril. BACKGROUND: The ACE inhibitors have become a cornerstone in the treatment of CHF, but whether high doses are more effective than low doses has not been fully elucidated, nor have the mechanisms involved in such a dose-related effect. METHODS: In a parallel group comparison, the effects of three doses of imidapril were examined. We studied 244 patients with mild to moderate CHF (New York Heart Association class II-III: +/-80%/20%), who were stable on digoxin and diuretics. Patients were treated for 12 weeks, and the main end points were exercise capacity and plasma neurohormones. RESULTS: At baseline, the four treatment groups were well-matched for demographic variables. Of the 244 patients, 25 dropped out: 3 patients died, and 9 developed progressive CHF (3/182 patients on imidapril vs. 6/62 patients on placebo, p < 0.05). Exercise time increased 45 s in the 10-mg group (p = 0.02 vs. placebo), but it did not significantly change in the 5-mg (+16 s), and 2.5-mg (+11 s) imidapril group, compared to placebo (+3 s). Physical working capacity also increased in a dose-related manner. Plasma brain and atrial natriuretic peptide decreased (p < 0.05 for linear trend), while (nor)epinephrine, aldosterone and endothelin were not significantly affected. Renin increased in a dose-related manner, but plasma ACE activity was suppressed similarly (+/-60%) on all three doses. CONCLUSIONS: Already within 3 months after treatment initiation, high-dose ACE inhibition (with imidapril) is superior to low-dose. This is reflected by a more pronounced effect on exercise capacity and some of the neurohormones, but it does not appear to be related to the extent of suppression of plasma ACE.     

Increased MPTP neurotoxicity in vesicular monoamine transporter 2 heterozygote knockout mice

The neurotoxic action of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) has been proposed to be attenuated by sequestration into intracellular vesicles by the vesicular monoamine transporter (VMAT2). The purpose of this study was to determine if mice with genetically reduced levels of VMAT2 (heterozygote knockout; VMAT2 +/-) were more vulnerable to MPTP. Striatal dopamine (DA) content, the levels of DA transporter (DAT) protein, and the expression of glial fibrillary acidic protein (GFAP) mRNA, a marker of gliosis, were assessed as markers of MPTP neurotoxicity. In all parameters measured VMAT2 +/- mice were more sensitive than their wild-type littermates (VMAT2 +/+). Administration of MPTP (7.5, 15, or 30 mg/kg, b.i.d.) resulted in dose-dependent reductions in striatal DA levels in both VMAT2 +/- and VMAT2 +/+ animals, but the neurotoxic potency of MPTP was approximately doubled in the VMAT2 +/- mice: 59 versus 23% DA loss 7 days after 7.5 mg/kg dose for VMAT2 +/- and VMAT2 +/+ mice, respectively. Dopaminergic nerve terminal integrity, as assessed by DAT protein expression, also revealed more drastic reductions in the VMAT2 +/- mice: 59 versus 35% loss at 7.5 mg/kg and 95 versus 58% loss at 15 mg/kg for VMAT2 +/- and VMAT2 +/+ mice, respectively. Expression of GFAP mRNA 2 days after MPTP was higher in the VMAT2 +/- mice than in the wild-type: 15.8- versus 7.8-fold increase at 7.5 mg/kg and 20.1- versus 9.6-fold at 15 mg/kg for VMAT2 +/- and VMAT2 +/+ mice, respectively. These observations clearly demonstrate that VMAT2 +/- mice are more susceptible to the neurotoxic effects of MPTP, suggesting that VMAT2-mediated sequestration of the neurotoxin into vesicles may play an important role in attenuating MPTP toxicity in vivo.     

Synthesis and evaluation of 5-aminosalicyl-glycine as a potential colon-specific prodrug of 5-aminosalicylic acid

OBJECTIVE: To estimate more precisely the risk of fetal loss and congenital abnormalities after maternal parvovirus B19 infection, and to assess the long term outcome for surviving infants. DESIGN: Prospective cohort study of pregnant women with confirmed B19 infection with follow up of the surviving infants. The rate of fetal loss in the study cohort was compared with that in pregnant women with varicella. SETTING: Cases reported by laboratories in England and Wales between 1985-1988 and 1992-1995. SAMPLE: Four hundred and twenty-seven pregnant women with B19 infection and 367 surviving infants of whom 129 were followed up at 7-10 years of age. METHODS: Questionnaires to obstetricians and general practitioners on outcome of pregnancy and health of surviving infants. Maternal infection confirmed by B19-specific IgM assay and/or IgG seroconversion. RESULTS: The excess rate of fetal loss in women with B19 infection was confined to the first 20 weeks of gestation and averaged 9%. Seven cases of fetal hydrops followed maternal infections between 9 and 20 weeks of gestation (observed risk 2.9%, 95% CI 1.2-5.9). No abnormalities attributable to B19 infection were found at birth in surviving infants (observed risk 0%, upper 95% CI 0.86%). No late effects were found at 7-10 years. CONCLUSIONS: Around 1 in 10 women infected before 20 weeks of gestation will suffer a fetal loss due to B19. The risk of an adverse outcome of pregnancy after this stage is remote. Infected women can be reassured that the maximum possible risk of a congenital abnormality due to B19 is under 1% and that long term development will be normal.     

High sensitivity and analyte capture with desorption/ionization mass spectrometry on silylated porous silicon

Silylation chemistry on porous silicon provides for ultrahigh sensitivity and analyte specificity with desorption/ionization on silicon mass spectrometry (DIOS-MS) analysis. Here, we report that the silylation of oxidized porous silicon offers a DIOS platform that is resistant to air oxidation and acid/base hydrolysis. Furthermore, surface modification with appropriate hydrophobic silanes allows analytes to absorb to the surface via hydrophobic interactions for direct analyte extraction from complex matrixes containing salts and other nonvolatile interferences present in the sample matrix. This enables rapid cleanup by simply spotting the sample onto the modified DIOS target and removing the liquid phase containing the interferences. This approach is demonstrated in the analysis of protein digests and metabolites in biofluids, as well as for the characterizing of inhibitors from their enzyme complex. An unprecedented detection limit of 480 molecules (800 ymol) for des-Arg(9)-bradykinin is reported on a pentafluorophenyl-functionalized DIOS chip.     

Human milk oligosaccharides. The rule in the health and development of the infants

Breast-feeding is the optimal mode of feeding for the normal full-term infant. Human milk composition knowledge has been basis for recommended dietary allowances for infants. Few studies about human milk carbohydrates have been done until the last decade. However, carbohydrates provide approximately 40-50% of the total energy content of breast milk. Quantitatively oligosaccharides are the third largest solute in human milk after lactose and fat. Each individual oligosaccharide is based on a variable combination of glucose, galactose, sialic acid, fucose and N-acetylglucosamine with many and varied linkages between them, thus accounting for the enormous number of different oligosaccharides in human milk. The oligosaccharides content in human milk varies with the duration of lactation, diurnally and with the genetic makeup of the mother. At present, a great interest in the roles of human milk oligosaccharides is raising. They act as a the soluble fibre in breast milk and their structure is available to act as competitive ligands protecting the breast-fed infant from pathogens and act as well as prebiotic. They may also act as source of sialic acid and galactose, essential for brain development. This is why today there is an increasing health and industrial interest in human milk oligosaccharides content, with the main purpose of incorporating them as new ingredients in infant nutrition.     

单排小桩复合桩墙支护结构设计计算方法

复合桩墙支护结构是一种由水泥土桩墙和竖向小桩通过钢筋砼压顶板联合构成的新型复合型支护结构体系.本文在全面总结复合桩墙支护体系结构类型及其计算模型基础上,结合现场试验研究和数值模拟,提出了单排小桩复合水泥土桩墙支护体系基于整体计算模式的设计计算方法,为同类型基坑工程的设计和施工提供了一定的技术参考.