It takes two to tango: the structure and function of LIM, RING, PHD and MYND domains.

LIM (Lin-11, Isl-1, Mec-3), RING (Really interesting new gene), PHD (Plant homology domain) and MYND (myeloid, Nervy, DEAF-1) domains are all zinc-binding domains that ligate two zinc ions. Unlike the better known classical zinc fingers, these domains do not bind DNA, but instead mediate interactions with other proteins. LIM-domain containing proteins have diverse functions as regulators of gene expression, cell adhesion and motility and signal transduction. RING finger proteins are generally associated with ubiquitination; the presence of such a domain is the defining feature of a class of E3 ubiquitin protein ligases. PHD proteins have been associated with SUMOylation but most recently have emerged as a chromatin recognition motif that reads the methylation state of histones. The function of the MYND domain is less clear, but MYND domains are also found in proteins that have ubiquitin ligase and/or histone methyltransferase activity. Here we review the structure-function relationships for these domains and discuss strategies to modulate their activity.

Assembly of fluorescent chimeric virus-like particles of canine parvovirus in insect cells.

Canine parvovirus (CPV) is a small non-enveloped ssDNA virus composed of the viral proteins VP1, VP2, and VP3 with a T=1 icosahedral symmetry. VP2 is nested in VP1 and the two proteins are produced by differential splicing of a primary transcript of the right ORF of the viral genome. The VP2 protein can be further proteolytically cleaved to form VP3. Previous studies have shown that VP1 and VP3 are unnecessary for capsid formation and consequently, that VP2 alone is sufficient for assembly. We have hypothesized that insertion of the enhanced green fluorescent protein (EGFP) at the N-terminus of VP2 could be carried out without altering assembly. To investigate the possibility to develop fluorescent virus-like particles (fVLPs) from such chimeric VP2 proteins, the corresponding fusion construct was abundantly expressed in insect cells. Confocal imaging indicated that the EGFP-VP2 fusion product was assembled to fluorescent capsid-like complexes. In addition, electron micrographs of purified EGFP-VP2 complexes showed that they displayed a very similar size and appearance when compared to VP2 VLPs. Further, immunolabelling of purified EGFP-VP2 VLPs showed the presence of EGFP within the structure. Fluorescence correlation spectroscopy (FCS) studies confirmed that fVLPs were very similar in size when compared to authentic CPV. Finally, feeding of mammalian cells susceptible to CPV infection with these fVLPs indicated that entry and intracellular trafficking could be observed. In summary, we have developed fluorescent virus-like nanoparticles carrying a heterologous entity that can be utilized as a visualization tool to elucidate events related to a canine parvovirus infection.

Correlates of cognitive status of old patients with isolated systolic hypertension: the Syst-Eur Vascular Dementia Project.

OBJECTIVE: To assess cognitive functions and their correlates for a dementia-free cohort of old patients with isolated systolic hypertension. DESIGN: Cross-sectional data from the randomization period of the European Trial in Elderly with Systolic Hypertension (Syst-Eur Vascular Dementia Project). SETTING: Sixteen European countries and Israel. PARTICIPANTS: We studied 2252 patients aged 60-100 years (mean 70). MAIN OUTCOME MEASURES: Mini Mental State Examination (MMSE) and Spearman correlation of MMSE scores to demographic data or blood pressure. RESULTS: The MMSE was successfully completed for 1474 women and 751 men. The baseline blood pressure averaged 173 +/- 10/86 +/- 6 mmHg (means +/- SD). Median age at which education of patients at school had stopped was 15 years. Men and women who consumed alcohol (28%) had median intakes of 8 and 3 g/day, respectively. The median MMSE score was 29 (range 15-30). The maximum score of 30 was attained by 609 (30%) subjects. Fifty-nine (3%) patients had a MMSE score of 23 or less. The MMSE score decreased with advancing age (r = -0.21, P < 0.001). Both for men and for women, it was positively correlated to the level of education (r = 0.30 and r = 0.32, P < 0.001). For women after adjustment for age and the level of education, the score was correlated negatively to systolic blood pressure (r = -0.07, P < 0.05) but positively to intake of alcohol (r = 0.06, P < 0.05). CONCLUSION: In a cohort of elderly patients with isolated systolic hypertension, baseline cognitive function measured in terms of the MMSE score was high, probably due to selective recruitment of patients who were not clinically demented. Blood pressure was a weak contributor to cognitive status compared with age and level of education. Baseline cognitive function of women was negatively and independently correlated to systolic blood pressure.

Women have a larger and less atherogenic low density lipoprotein particle size than men.

Some epidemiological studies have shown that serum total cholesterol increases with age. especially in women. On the other hand, the risk of coronary artery disease is smaller in women than in men. Earlier studies have shown that a small dense low density lipoprotein (LDL) is more atherogenic than a large LDL. We studied LDL size and apolipoprotein E (apo E) phenotypes in premenopausal and postmenopausal women and in men at the same age. In this study 342 subjects participating in a health screening study were examined. There were four subgroups: 40-year-old men (n = 85), 40-year-old women (n = 80), 70-year old men (n = 88) and 70-year-old women (n = 89). In the present study LDL size was larger (P < 0.01) in women (26.39 +/- 0.07 nm) than in men (25.95 +/- 0.07 nm). We found that LDL size correlated highly positively (r = 0.606; P < 0.001) with serum high density lipoprotein (HDL) concentration and inversely with serum triglyceride concentration (r = -0.627; P < 0.001). Measuring serum HDL cholesterol and triglycerides in health screening studies gives information indirectly about LDL size and its atherogenicity. Apo E phenotype was not significantly associated with serum triglycerides, but was associated with LDL size, LDL cholesterol, total cholesterol and HDL cholesterol. In our sample LDL size decreased and LDL cholesterol and total cholesterol increased according to the most prevalent apo E phenotypes in the order E2/3, E3/3, E3/4 and E4/4. Subjects with phenotype apo E4/4 had the smallest LDL size (25.70 +/- 0.19 nm), the highest total cholesterol (6.53 +/- 0.35 mmol/l) and the lowest HDL cholesterol values (1.28 +/- 0.04 mmol/l). We conclude that there was a significant interaction between sex and age in serum total cholesterol which was highest in older women. However, their LDL size was larger and their LDL is less atherogenic. Apo E phenotype had a significant influence on LDL size.

Nitrendipine in older patients with isolated systolic hypertension: second progress report on the SYST-EUR trial.

This report from the double-blind placebo-controlled SYST-EUR trial investigated whether modern antihypertensive drugs are suitable for maintaining long-term BP control in older (> or = 60 years of age) subjects with isolated systolic hypertension (SBP 160-219 mmHg and DBP < 95 mmHg). Active treatment consisted of nitredipine (10-40 mg/day) with the possible addition of enalapril (5-20 mg/day) and hydrochlorothiazide (12.5-25 mg/day), if necessary to reduce SBP to < 150 mmHg and by > or = 20 mmHg. Matching placebos were used in the control group. This analysis was restricted to 18 months of follow-up. The placebo (n = 456) and active treatment (n = 485) groups had similar characteristics at randomisation (sitting pressure 176/85 mmHg; age 73 years). SBP fell (P < 0.001) on average 10 mmHg more on active treatment than on placebo and DBP 4 mmHg more. Fewer patients remained on monotherapy in the placebo than in the active treatment group (P < 0.001); on placebo the second and third line medications were started earlier (P < 0.001). Nitrendipine tablets were discontinued in nine patients on placebo and in 29 patients assigned to active treatment (P < 0.001). In conclusion, a significant BP reduction can be achieved and maintained in older patients with isolated systolic hypertension treated with a calcium antagonist (associated with a converting-enzyme inhibitor and a thiazide, where necessary). Whether this BP reduction results in a clinically meaningful decrease of cardiovascular complications is under investigation.

Prevalence of depressive symptoms and depression in elderly Finnish home nursing patients and home help clients.

Depressive symptoms in a population (N = 419) aged 65 years or over and receiving home nursing, home help or both were assessed by postal questionnaires including the Zung self-rating depression scale (SDS). Eighty-six percent participated, and 38 percent of both men and women scored 45 raw sumpoints or more in the SDS. The mean of the raw sumpoints was 42.1 (+/- 9.6) for men (N = 100) and 41.4 (+/- 9.0) for women (N = 238, the difference being nonsignificant. Home help clients scored less than home nursing patients or patients receiving both home nursing and home help. The population scoring 45 raw SDS sumpoints or more was investigated by a general practitioner, and the diagnosis of depression was made according to DSM III-criteria. The clinical investigations showed 26 percent of both men and women who participated to be depressive. Chronic depression was the most common class, followed by atypical depression. About two thirds of the depressive men and half of the depressive women were 'new' cases in that it had not been realized earlier that they suffer from depression. Atypical depression was the class where underdiagnozing was most evident. Among elderly men psychomotor retardation, libido loss, anorexia and indecisiveness and among elderly women psychomotor retardation, indecisiveness, emptiness and diurnal variation were common symptoms of depression.