[Interactions between nucleic acid bases. New parameters of potential functions and energy minima]

The parameters of atom-atom potential functions suggested by one of the authors in 1979-1986 were slightly changed. The changes were performed to achieve a better agreement with experimental data of interaction energy values in global minima and hydrogen bond lengths. These changes resulted in better accord with experimental values of distances between the layers in DNA monomer crystals and between the base pairs in oligonucleotide duplexes. The refined potential functions were used to calculate the energy of interactions between nucleic acid bases in various mutual positions. The calculations revealed a few types of mutual base arrangements in minima of interaction energy for each pairwise base combination. A new type of minima was found, which correspond to a nearly perpendicular arrangement of base rings and the formation of the intermolecular hydrogen bond.

HIV-1 infection and AIDS dementia are influenced by a mutant MCP-1 allele linked to increased monocyte infiltration of tissues and MCP-1 levels

Studies in humans and in experimental models of HIV-1 infection indicate an important role for monocyte chemoattractant protein-1 (MCP-1; also known as CC chemokine ligand 2), a potent chemoattractant and activator of mononuclear phagocytes (MP) in the pathogenesis of HIV-associated dementia (HAD). We determined the influence of genetic variation in MCP-1 on HIV-1 pathogenesis in large cohorts of HIV-1-infected adults and children. In adults, homozygosity for the MCP-1 -2578G allele was associated with a 50% reduction in the risk of acquiring HIV-1. However, once HIV-1 infection was established, this same MCP-1 genotype was associated with accelerated disease progression and a 4.5-fold increased risk of HAD. We examined the molecular and cellular basis for these genotype-phenotype associations and found that the mutant MCP-1 -2578G allele conferred greater transcriptional activity via differential DNA-protein interactions, enhanced protein production in vitro, increased serum MCP-1 levels, as well as MP infiltration into tissues. Thus, MCP-1 expression had a two-edged role in HIV-1 infection: it afforded partial protection from viral infection, but during infection, its proinflammatory properties and ability to up-regulate HIV-1 replication collectively may contribute to accelerated disease progression and increased risk of dementia. Our findings suggest that MCP-1 antagonists may be useful in HIV-1 infection, especially for HAD, and that HIV+ individuals possessing the MCP-1 -2578G allele may benefit from early initiation of antiretroviral drugs that effectively cross the blood-brain barrier. In a broader context, the MCP-1 -2578G allele may serve as a genetic determinant of outcome of other disease states in which MP-mediated tissue injury is central to disease pathogenesis.

Determination and Interpretation of Total and Transversal Linear Efficiencies in Push–Pull Ventilation Systems for Open Surface Tanks

A real-scale pilot installation simulating an open surface treatment tank with a push-pull ventilation system has been designed. From experiments carried out, typical representations of the total and transversal linear efficiencies show that when total efficiency is related to push flow rate, taking as a parameter the pull flow rate, a parabolic profile is obtained with a maximum point or plateau that increases as the pull flow increases. When the transversal linear efficiency is analysed, three general zones where losses occur to the exterior can be detected: (i) when the push flow rate is low, any distortion in the wall jet, whether external (e.g. in the air flow inside the workshop) or internal (e.g. thermal effects), provokes an escape from contaminant; (ii) in the impact zone, where the push flow impacts on the tank surface, distortion increases as the push flow rate increases; (iii) when the push/pull flow rate ratio increases and preferential currents are produced inside the exhaust hood, these escape and cause substantial losses in efficiency.

Primary cerebral sarcoid granuloma: the importance of definitive diagnosis in the high-risk patient population

Sarcoidosis of the central nervous system has been variously reported in 5-15% of all sarcoid patients. However, presentation of sarcoidosis as an isolated 'intracranial tumor' is rare. A 35-year-old African-American woman presented with intractable headaches. Neuroimaging revealed a tumor that was suggestive of a glioma or meningioma or metastasis. The symptoms did not respond to steroids, and an open biopsy of the lesion revealed non-caseating granuloma. A thorough work-up for systemic sarcoidosis was negative. The patient remains symptom-free at a 2-year follow-up. Primary sarcoid granuloma of the brain is rare. Once systemic disease has been excluded, early tissue diagnosis is crucial. This is particularly relevant for patients in the high-risk population before considering empirical radiosurgery.

A strong signature of balancing selection in the 5' cis-regulatory region of CCR5

CCR5 encodes a cell surface chemokine receptor molecule that serves as the principal coreceptor, with CD4, for HIV-type 1 (HIV-1). Varied HIV-1 susceptibility and time to progression to AIDS have been associated with polymorphisms in CCR5. Many of these polymorphisms are located in the 5' cis-regulatory region of CCR5, suggesting that it may have been a target of natural selection. We characterized CCR5 sequence variation in this region in 400 chromosomes from worldwide populations and compared it to a genome-wide analysis of 100 Alu polymorphisms typed in the same populations. Variation was substantially higher than expected and characterized by an excess of intermediate-frequency alleles. A genealogy of CCR5 haplotypes had deep branch lengths despite markedly little differentiation among populations. This finding suggested a deviation from neutrality not accounted for by population structure, which was confirmed by tests for natural selection. These results are strong evidence that balancing selection has shaped the pattern of variation in CCR5 and suggest that HIV-1 resistance afforded by CCR5 5' cis-regulatory region haplotypes may be the consequence of adaptive changes to older pathogens.

Influence of push element geometry on the capture efficiency of push-pull ventilation systems in surface treatment tanks

A full-scale installation which simulates a surface treatment tank provided with a push-pull ventilation system has been designed. This study examines the influence of the geometry of the push element on the capture efficiency of the system. It is observed that: (i) capture efficiency increases with the number of holes because of the continuous curtain formed, the size of the holes having no significant effect within the range studied (5-20 mm diameter); (ii) the push element is best supported on the tank wall so that no air from outside penetrates below the emitting jets because in this way the impact of the curtain on the tank occurs earlier and losses are less; (iii) the best results are obtained when the holes are directed downwards towards the tank surface at an angle of between 22 and 45 degrees.

Identification of peptide sequences specific for serum antibodies from human papillomavirus-infected patients using phage display libraries

Three random phage display peptide libraries were screened with sera from human papillomavirus (HPV)-infected patients to characterize the specificities of antibodies present in patients' sera and to identify molecules that correspond to or mimic natural epitopes; 141 phage clones were randomly selected in three rounds of bioselection and their binding properties were analyzed in ELISA using sera from 36 patients with confirmed HPV 16 infection and 24 healthy control female blood donors. Sixteen of 36 (44%) patients' sera reacted with at least 1 phage clone, and only 2 of 24 female donors' sera showed positive reaction with 1 of the selected clones. We conclude that the combination of various disease-specific epitopes generated by screening of phage display peptide libraries may potentially lead to a multicomponent diagnostic assay for the early detection of HPV infection and precancerous cervical lesions, making possible the prevention of one of the most common cancers in women.

Italian drug information centres: benchmark report

OBJECTIVE

Pharmacist-operated Drug Information Centres (DICs) in Italy were surveyed to gather current information concerning the status, availability and scope of their services.

METHODS

40 DICs were identified and a questionnaire was mailed to them. Topics covered in the questionnaire included staffing, resources, activities and services. The results were compared with previous survey results to identify trends.

RESULTS

Information from 36 DICs was analysed (response rate = 90%). Almost all regions of the country are represented. Pharmacists, part-time or full-time, are the most frequent employees working in the DICs. 91% of DICs participate in the P/T committee, 74% takes part in the technical scientific committee for clinical experimentation and/or to the Medical Ethics committee and 60% participate in the hospital infection committee. 90% of DICs produce newsletters and/or bulletins and are involved in research projects. Regarding the question-answer service, requests are mainly concerned with clinical comparative efficacy, therapeutic use, adverse effects. The most frequent users are physicians (67%) followed by pharmacists (16%) while other professionals use DICs to lesser extent. The most frequently used information sources, include "Goodman and Gilman's the pharmacological basis of therapeutics", Martindale: the Extra Pharmacopeia and Physician's Desk Reference; journals such as the Medical Letter, Adverse Drug Reactions Bulletin and Drug and Therapeutic Bulletin, Micromedex, Medline and IOWA databases. Data collected through the questionnaire and details about organisation and activity of Italian DICs are available in "Eupharma", the web-site of the Italian Society of Hospital Pharmacy (SIFO) at the URL http://www.sifo.it.

CONCLUSION

The results parallel the European and American trends. In future communication and collaboration at European level could help to identify best practice models that would result in the standardisation of the activities and in the harmonisation of programs in common areas of interest.

Two diacylated malvidin glycosides from Petunia hybrida flowers

Two novel diacylated and two known anthocyanins were isolated from violet flowers of Petunia hybrida cv Festival. The new anthocyanins are malvidin 3-O-(6-O-(4-O-(4-O-(6-O-feruloyl-beta-D-glucopyranosyl)-E-p-coumaroyl)-alpha-rhamnosyl)-beta-D-glucopyranoside)-5-beta-D-glucopyranoside and malvidin 3-O-(6-O-(4-O-(4-O-(6-O-E-p-coumaroyl-beta-D-glucopyranosyl)-E-p-coumaroyl)-alpha-rhamnosyl)-beta-D-glucopyranoside)-5-beta-D-glucopyranoside. The two known pigments are the 3-caffeoylglucosyl-p-coumaroylrutinoside-5-glucosides of malvidin and petunidin.

Barrel cortex critical period plasticity is independent of changes in NMDA receptor subunit composition

The regulation of NMDA receptor (NMDAR) subunit composition and expression during development is thought to control the process of thalamocortical afferent innervation, segregation, and plasticity. Thalamocortical synaptic plasticity in the mouse is dependent on NMDARs containing the NR2B subunit, which are the dominant form during the "critical period" window for plasticity. Near the end of the critical period there is a gradual increase in the contribution of NR2A subunits that happens in parallel to changes in NMDAR-mediated current kinetics. However, no extension of the critical period occurs in NR2A knockout mice, despite the fact that NMDA subunit composition and current kinetics remain immature past the end of the critical period. These data suggest that regulation of NMDAR subunit composition is not essential for closing the critical period plasticity window in mouse somatosensory barrel cortex.

Comparison of clinical outcome of stripping and CHIVA for treatment of varicose veins in the lower extremities

The purpose of this nonrandomized case-review study was to compare the outcome of stripping and CHIVA for treatment of varicose veins in the lower extremities in our department. Outcome was evaluated by independent physicians. A total of 85 patients underwent saphenous vein stripping in association with phlebectomy and 90 patients underwent CHIVA cure. The duration of follow-up was 3 years. Study criteria were (1) presence of varicose veins as a cause of failure (1.1% in the CHIVA group vs. 15.3% in the stripping group), (2) appearance of telangiectasia (8.9% in the CHIVA group vs. 65.9% in the stripping group), (3) patient dissatisfaction rate (3.3% in the CHIVA group vs. 16.5% in the stripping group), (4) postoperative symptoms as a cause of failure (1.1% in the CHIVA group vs. 21.2% in the stripping group), and (5) saphenous nerve injury (1 patient in the CHIVA group vs. 16 in the stripping group). Differences between all five criteria were significantly in favor of the CHIVA group as compared to saphenous vein stripping with phlebectomy. Clinical results at 3 years are better for patients treated with CHIVA than stripping with regard to presence of varicose veins, clinical symptoms, presence of telangiectasia, cosmetic satisfaction, and neurologic complications. Data in our series of CHIVA treatments are comparable to those reported in the literature and better than those described in three series of stripping procedures with 3-year follow-up. A prospective randomized study is now underway to confirm these findings.

Corrective osteotomy for symptomatic increased ulnar tilt of the distal end of the radius

Twelve wrists in 10 patients with a mean age of 23.6 years were treated for symptomatic increased ulnar inclination of the joint surface with corrective osteotomy of the radius. Diagnoses included mild ulnar dysplasia, posttraumatic deformity, Madelung's disease, and multiple hereditary exostosis. All patients had radial-sided wrist pain and an ulnarly displaced arc of radioulnar deviation. Preoperative radiographs showed excessive ulnar inclination of the distal radius, ulnar carpal translation, adaptive carpal malalignment, and frequent distal radioulnar joint incongruency. The patients had decreased pain and improved wrist function at a mean of 5.1 years (range, 2-10 years) after surgery. Average radial deviation changed from 3 degrees to 16 degrees and ulnar deviation from 48 degrees to 29 degrees; flexion/extension and pronosupination remained unchanged. Realignment of the wrist was shown radiographically by a change of ulnar inclination of the radius from 33 degrees to 21 degrees, an increase in scaphoid height from 16.4 to 20.4 mm, and reversal of ulnar carpal translation as shown by an increase in lunate-covering ratio of 64% to 77%. Reduction of the ulnar inclination to normal values by corrective radial osteotomy restores a more physiologic range of motion, decreases symptomatic wrist pain, reverts adaptive carpal changes to normal, increases lunate coverage, and may prevent abnormal cartilage overload in the ulnar compartment of the wrist.

Concordance between the CC chemokine receptor 5 genetic determinants that alter risks of transmission and disease progression in children exposed perinatally to human immunodeficiency virus

If CC chemokine receptor 5 (CCR5)-dependent mechanisms at the time of initial virus exposure are important determinants of virus entry and disease outcome, then the polymorphisms in CCR5 that influence risk of transmission and disease progression should be similar; this hypothesis was tested in a cohort of 649 Argentinean children exposed perinatally to human immunodeficiency virus type 1 (HIV-1). Two lines of evidence support this hypothesis. First, CCR5 haplotype pairs associated with enhanced risk of transmission were the chief predictors of a faster disease course. Second, some of the haplotype pairs associated with altered rates of transmission and disease progression in children were similar to those that we previously found influenced outcome in European American adults. This concordance suggests that CCR5 haplotypes may serve as genetic rheostats that influence events occurring shortly after initial virus exposure, dictating not only virus entry but, by extension, also the extent of early viral replication.

Pancreatic transplantation and subsequent graft surveillance by pancreatic portal-enteric anastomosis and temporary venting jejunostomy

OBJECTIVE

To evaluate portal-enteric (PE) pancreas and kidney transplantation with venting jejunostomy (VJ) for its efficacy, safety, and reproducibility.

SUMMARY BACKGROUND DATA

Simultaneous pancreas and kidney transplantation for patients with long-standing insulin-dependent diabetes mellitus that progresses to renal failure has revolutionized their treatment and quality of life. A current clinical focus is to refine the technical aspects of this procedure. Simultaneous pancreas and kidney transplantation with PE anastomosis with VJ appears to offer several advantages over bladder drainage. VJ allows initial decompression of the enteric anastomosis, monitoring of pancreatic function by ostomy amylase, and simple access for endoscopic evaluation and biopsy of the allograft.

METHODS

Simultaneous pancreas and kidney transplantation with VJ was performed in 21 patients from December 1996 to October 2000 at Willis Knighton/LSU Regional Transplant Center. All patients had long-standing insulin-dependent diabetes mellitus and subsequent renal failure. They were evaluated at the time of surgery by a multidisciplinary transplant team and monitored for numerous factors, including length of hospital stay, immunosuppressive regimen, and ischemia times. All patients had intermittent visual and biochemical evaluation of pancreatic secretions monitored by means of the VJ.

RESULTS

Of the 21 patients, 10 were women and 11 were men. Four patients were black and 17 were white. The mean age at transplantation was 38 years; average human leukocyte antigen (HLA) match was one; and average cold ischemia time was 12 hours. The median hospital stay was 16 days. Four episodes of postoperative bleeding requiring exploration occurred in four patients. Postoperative wound infections developed in four patients. There were 12 episodes of rejection in nine patients. All patients with suspected acute pancreatic rejection underwent endoscopy by means of the VJ and duodenal biopsy for evaluation. Two patients lost pancreatic function subsequent to kidney failure, one secondary to noncompliance and the other as a result of hemolytic-uremic syndrome. Patient, kidney, and pancreatic survival rates were 100%, 90%, and 90%, respectively. The mean follow-up period was 25 (range 2-48) months.

CONCLUSION

The authors believe that PE pancreatic drainage with VJ is a more physiologic method to perform pancreatic transplantation than bladder drainage. PE drainage allows rapid diagnosis of acute rejection and anastomotic leak and provides a simple way to monitor ostomy amylase and transplant duodenal bleeding. This technique is safe and has minimal associated complications.

Global survey of genetic variation in CCR5, RANTES, and MIP-1alpha: impact on the epidemiology of the HIV-1 pandemic

Expression of CC chemokine receptor 5 (CCR5), the major coreceptor for HIV-1 cell entry, and its ligands (e.g., RANTES and MIP-1alpha) is widely regarded as central to the pathogenesis of HIV-1 infection. By surveying nearly 3,000 HIV+ and HIV- individuals from worldwide populations for polymorphisms in the genes encoding RANTES, MIP-1alpha, and CCR5, we show that the evolutionary histories of human populations have had a significant impact on the distribution of variation in these genes, and that this may be responsible, in part, for the heterogeneous nature of the epidemiology of the HIV-1 pandemic. The varied distribution of RANTES haplotypes (AC, GC, and AG) associated with population-specific HIV-1 transmission- and disease-modifying effects is a striking example. Homozygosity for the AC haplotype was associated with an increased risk of acquiring HIV-1 as well as accelerated disease progression in European Americans, but not in African Americans. Yet, the prevalence of the ancestral AC haplotype is high in individuals of African origin, but substantially lower in non-Africans. In a Japanese cohort, AG-containing RANTES haplotype pairs were associated with a delay in disease progression; however, we now show that their contribution to HIV-1 pathogenesis and epidemiology in other parts of the world is negligible because the AG haplotype is infrequent in non-Far East Asians. Thus, the varied distribution of RANTES, MIP-1alpha, and CCR5 haplotype pairs and their population-specific phenotypic effects on HIV-1 susceptibility and disease progression results in a complex pattern of biological determinants of HIV-1 epidemiology. These findings have important implications for the design, assessment, and implementation of effective HIV-1 intervention and prevention strategies.

The validity of self-reported seatbelt use: Hispanic and non-Hispanic drivers in El Paso

The validity of self-reported seatbelt use among low belt use populations has not been evaluated directly, despite the importance of such data for estimating the effectiveness of community-wide interventions and compliance with state laws. To address this gap in knowledge 612 drivers were recruited from convenience stores located in 12 randomly generated zip code areas located in El Paso, TX. Self-reported seatbelt use was compared with observed seatbelt use in a single sample of participants. Both data sets were collected almost contemporaneously and no participant was aware of having their seatbelt use observed. Hispanic (n = 388) and white/non-Hispanic (n = 126) drivers over reported seatbelt use by 27 and 21%, respectively. These findings suggest that response bias within low belt use populations may be greater than suggested by state and national data.

The HOS test and its relationship to fertility in the stallion

The hypo-osmotic test has been used successfully on equine semen and was considered to be a simple and accessible method which could be a useful addition to routine equine semen analysis. It was therefore of interest to determine whether the hypo-osmotic test is significantly correlated to proposed criteria of fertility. The stallions were divided into two groups on the basis of threshold levels of fertility. A significant difference (P<0.05) was found between the two groups for the following parameters: progressive motility, morphologically normal spermatozoa, percentage of swelling with the hypo-osmotic test, percentage of pregnant mares and number of services per pregnancy. The hypo-osmotic test provided a simple evaluation of membrane function and the results obtained show stallions with low swelling scores (<40%) to be of doubtful fertility. The hypo-osmotic test was not correlated with percentage of pregnant mares but showed a tendency to correlate with the number of services per pregnancy, therefore it could be an additional method for evaluating stallion fertility. Further studies are needed to confirm this observation.