Switzerland: new medical informatics curriculum

Swiss Society for Medical Informatics (SSMI) started to build a postgraduate curriculum in medical informatics a year ago. The aim is to build a curriculum with different modules allowing the healthcare professionals to follow individual path in order to fulfill their objectives. The professionals who could benefit from the curriculum are physicians, nurses, medical assistants, computer specialists in the healthcare domain. Different levels of certificates or diplomas will be given depending on the number of modules taken and the professional background. Modules can be taken in different ways: universities, hospitals, distance learning.... The kickoff meeting for the leading group of this curriculum chaired by Dr Denz from Zurich was held on June 5 and 6 1998 was Swiss Nursing informatics group is active in this field. Working Group 5 (WG5) "Nursing Informatics in Europe" is supporting countries efforts in building nursing informatics curriculum. Promoting links between specialists in this domain in different countries. Selecting relevant Websites to be used. Disseminating information to country members of WG5.

Porcine IgA allotypes are not equally transcribed or expressed in heterozygous swine

The prediction of 1:1 expression of constant region allotypes in heterozygous animals assumes that productive VDJ rearrangements occur at random between chromosomes, switch recombination is random, there is no allele-related defect in switching and there is no selection for a B-cell receptor bearing a certain constant region allotype. In data reported here, this prediction was often not fulfilled for the transcripts encoding the IgAa and IgAb alleles of porcine IgA including those from late term fetal piglets that are not in contact with environmental antigens or maternal regulatory factors. In the spleen, thymus, mesenteric lymph node (MLN), ileal Peyer patches, parotid gland and PBLs of 5-week-old conventionally-reared Duroc pigs, ratios of IgAa to IgAb transcripts as high as 4:1 were observed. Since White Cross animals had significantly higher levels of IgAb than IgAa (some >3-fold), a allele-linked switch defect cannot explain the deviation from the expected 1:1 ratio. When the IgAa:IgAb ratios in older Durocs and those reared at a different site were studied, no evidence for breed dependence of differential transcription was found. Total serum IgA levels paralleled total transcript levels in PBLs while particularly in White Cross animals, the IgAa:IgAb ratio in serum was higher in many animals than the IgAa:IgAb transcript ratio in their PBLs. We conclude that deviations from the expected 1:1 ratio of allotype transcripts and secreted IgA in young pigs is normal and deviations from this ratio also occur during fetal life in the absence of environmental antigens and maternal regulatory factors. We speculate that postnatal deviations result from: (A) exposure to environmental antigens that selectively expand B-cells expressing V(H) gene alleles linked to either IgAa or IgAb or (B) some form of colostrum-dependent regulation. Pre-natal regulation may depend on the selection of B-cells bearing certain V(H) or C(H) encoded BCRs by stromal ligands such as fetal B-cell superantigens.

The liposuction apparatus "suspension device": hi-plane liposculpture

BACKGROUND

The improvement of liposuction equipment and techniques has resulted in a cumbersome operating room array of aspirator hoses, irrigation/infiltration tubing, and the insulated command and control wiring of current ultrasonic or power liposuction devices. This situation is further complicated by the presence of a second surgeon, the concomitant use of additional traditional or ultrasonic cannulas, and the suction hose of a second aspirator.

OBJECTIVE

To solve the problems of sterility and operating room organization, the authors describe a simple, releasable suspension design.

METHOD

This apparatus can be temporarily or permanently installed in minutes and is easily maintained to control numerous sterile hoses and wires required for certain liposuction procedures.

RESULTS

This suspension method appeared to enhance the efficiency and ease of use by single and dual surgeons during cases utilizing ultrasonic and nonultrasonic cannulas. The time savings and ease of use was most noticeable in cases of dual surgeons using both ultrasonic and nonultrasonic systems simultaneously. In addition, surgical personnel were freed for other tasks. Single-surgeon, traditional liposuction was less notably facilitated in terms of speed and fewer personnel. However, wiring and tubing control is facilitated in any case.

CONCLUSION

A simple liposuction suspension system facilitates the liposuction procedure to varying degrees depending upon the number of surgeons and devices in simultaneous use.

Antibody repertoire development in fetal and newborn piglets, III. Colonization of the gastrointestinal tract selectively diversifies the preimmune repertoire in mucosal lymphoid tissues

Changes in the VH-region repertoire of isolator piglets reared for 6 weeks under germ-free (GF) conditions and those colonized (COL) with a defined exclusion flora on the 1st day of life were compared. Although serum immunoglobulin levels were 20-100-fold higher in COL piglets than GF piglets, an analysis of peripheral blood B cells (PBBs) indicated that: GF and COL piglets used the same four VH genes and two DH segments during the 6-week period; proportional usage of VH genes and DH segments was the same as in fetal animals; and VH and DH usage did not differ between COL and GF animals. This pattern differed from the PBBs from 6-week-old conventional (CONV) piglets. When the sequences of 73 splenic CDR3 segments were analysed, DH usage and mutation frequency were the same in sequences from both 6-week-old GF and COL piglets; mutations were infrequent and occurred with the same frequency as in 110-day fetal spleen. However, the median CDR3 length in COL piglets was shifted upward due to 3' DH N-nucleotide additions. Neither COL nor GF animals made specific serum antibodies to phosphoryl choline given parenterally on a T-cell dependent carrier. In contrast to the near absence of a colonization effect in PBBs and splenic DNA, rearranged variable heavy-chain gene segments (VDJs) recovered from the DNA of mucosal lymphoid tissues of COL piglets showed pronounced differences from those recovered from GF animals in usage of DHA-, DHB-and VHB- and in the frequency of point mutation. The mucosal VDJ transcripts and those from the spleen were similarly affected by colonization. This effect on mucosal lymphoid tissue was consistent with the five-fold selective increase in serum immunoglobulin A (IgA) levels relative to IgM and IgG. Comparison of IgM and IgA transcripts from mucosal tissues suggested that IgA and IgM clones diversify in parallel. Our findings are the first to show that colonization of the gastrointestinal tract of offspring separated from their mothers, differs from 'conventionalized' GF animals in that colonization preferentially influences diversification and expansion of the preimmune IgM and IgA repertoire in mucosal lymphoid tissues but not in PBBs and seldom/modestly in VDJs from splenic DNA.

Triglyceride-lowering effect of omega-3 LC-polyunsaturated fatty acids--a review

There is increasing evidence that serum triglycerides are a significant and independent risk factor for CVD. The aim of this report is to review recent literature pertinent to the triglyceride-lowering effect of omega-3 long chain polyunsaturated fatty acids (LC-PUFA). Animal data are not considered because they are difficult to extrapolate to the human situation. A large body of evidence derived from epidemiological studies and clinical trials has consistently demonstrated that this effect is dose-dependent and can be achieved by diet. The smallest amount of omega-3 LC-PUFA needed to significantly lower serum triglycerides appears to be approximately 1 g/day as provided by a fish diet. Use of fish oil administering as little as 0.21 g EPA and 0.12 g DHA per day significantly lowered serum triglycerides in hyperlipidemics. In normolipidemics, a daily intake of 0.17 g EPA and 0.11 g DHA, given as a fish oil supplement, induced a non-significant reduction of 22%. These findings must be considered as preliminary and warrant further research. Intake of omega-3 LC-PUFA is frequently reported to modestly increase LDL cholesterol. However, in normo- or slightly hyperlipidemic individuals who received omega-3 LC-PUFA for 4 months or longer, changes of LDL cholesterol were not significantly different from a placebo group. Both EPA and DHA lower serum triglycerides, but they may have a differential effect on lipoproteins. Intake of omega-3 LC-PUFA in the amount mentioned above is safe.

Modulation of antigen trafficking to MHC class II-positive late endosomes of enterocytes

BACKGROUND & AIMS

Oral tolerance is recognized as a central immunoregulatory phenomenon. The mechanisms of its induction remain unclear, and the role of the intestinal epithelial cells that are able to present antigens to T lymphocytes is poorly understood. In this report, we analyze under in vivo conditions the intracellular targeting of mucosally administered ovalbumin (OVA) to major histocompatibility complex (MHC) class II antigen containing compartments of enterocytes and compare these pathways between BALB/c and SCID mice, the latter being unable to generate a transferable tolerogenic moiety after a feed of OVA.

METHODS

OVA, lysosome-associated membrane proteins (LAMP-1), and MHC class II antigens were localized in jejunal biopsy specimens of BALB/c and SCID mice at 0, 5, 10, 20, 40, 60, and 120 minutes after a single feed with OVA by fluorescence and electron microscopy.

RESULTS

Ten minutes after oral administration, OVA was transported to the proximity of MHC class II antigens within LAMP-1-positive vacuoles and to the basolateral membrane of enterocytes from BALB/c strain mice. However, in SCID mice, OVA reached the paracellular spaces during the same time period through LAMP-1-negative vacuoles of enterocytes, which lacked MHC class II antigens.

CONCLUSIONS

Orally administered OVA is rapidly targeted to late endosomes containing LAMP-1 and MHC class II antigens in enterocytes of BALB/c mice but not in SCID mice bred on a BALB/c background. We suggest that this targeting process within the enterocytes is one of the requirements for the induction of oral tolerance.

[Retinitis pigmentosa, terminal renal insufficiency and Caroli syndrome: new associations with Opitz trigonocephaly syndrome]

We report on a new patient with Opitz trigonocephaly syndrome. In addition to the findings typical of this mental retardation syndrome, the present patient has retinitis pigmentosa, Caroli's syndrome and renal failure, which is undergoing hemodialysis. This association is never observed before in patients with Opitz trigonocephaly syndrome. This case demonstrate, that with increased survival of patients with mental retardation syndromes, the phenotypes possible are modified.

Myocardial protection with monophosphoryl lipid-A against aortic cross clamping-induced global stunning

BACKGROUND

Monophosphoryl lipid-A (MLA) has a late window (24 hours) of cardioprotection against acute myocardial infarction. It is not known whether MLA, administered, 24 hours before surgery, attenuates intraoperative ventricular dysfunction "stunning" associated with aortic cross-clamping and reperfusion during elective cardiac surgery. We determined the dose-response relationship between MLA and ventricular function in a canine model of global myocardial stunning in the absence of necrosis. The role of expression of inducible heat shock protein 70 (HSP 70i) was also investigated.

METHODS

Mongrel dogs (n = 32) were intravenously injected with either a vehicle solution or 3, 5, 10, 35 ug/kg MLA. Twenty four hours later, dogs were anesthetized and instrumented, in situ, to monitor the left ventricular performance (the slope of regression between stroke-work and end diastolic length). Tissue samples were obtained to determine HSP70i using immunoblot analysis. After a period of equilibration on cardiopulmonary bypass, the aortic cross-clamp was applied at normothermia for 30 minutes followed by 60 minutes of reperfusion. ATP and catabolites were determined in transmural myocardial biopsies. Triphenyl-tetrazolium chloride (TTC) staining was used to determine myocardial necrosis.

RESULTS

MLA treatment did not alter myocardial contractility or ATP metabolism. Global ischemia resulted in about 50% depletion of ATP and remained depressed during reperfusion in all groups. MLA-treated hearts had improved functional recovery in a dose dependent-manner. Significant recovery was observed at the highest dose (35 ug/kg) compared to the control group. Immunoblot analysis demonstrated significant increase in HSP 70i in the MLA-treated hearts.

CONCLUSIONS

MLA exhibits a delayed (24 hours) window of protection against myocardial stunning associated with aortic cross-clamping. HSP70i expression may play a role in MLA-mediated cardioprotection.

Criteria for selective screening of cervical Chlamydia trachomatis infection in women attending private gynecology practices

OBJECTIVE

To develop a screening strategy for Chlamydia trachomatis in private gynecology practices.

STUDY DESIGN

Forty-six gynecologists in the greater Paris area systematically screened all consecutive female attenders during one week. Endocervical swabs were tested by enzyme immunoassay, and, if positive, was further confirmed by direct fluorescent antibody test.

RESULTS

Overall (out of 1893 women tested), the chlamydia prevalence was 0.8% (95% confidence interval: 0.32-1.2%). Among women younger than 21 years, the prevalence was 5.2% (95%, CI 0.8-9.6). Having had a new sexual partner in the last year was associated with chlamydial infection, independent of age. However, half of the infected women had not had a new partner.

CONCLUSION

Even in this low risk population, the prevalence was high among young women. Most of these infections would probably not have been detected. We developed a strategy which would have detected 81% of chlamydia positive women by testing only one third of the patients.

Lack of mutual pharmacokinetic interaction between cerivastatin, a new HMG-CoA reductase inhibitor, and digoxin in healthy normocholesterolemic volunteers

The potential mutual interaction between cerivastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor, and digoxin was assessed in this nonmasked, nonrandomized, multiple-dose study. The effect of cerivastatin 0.2 mg on mean plasma digoxin levels and the effect of digoxin on the single-dose pharmacokinetics of cerivastatin were assessed in 20 healthy normocholesterolemic men between 18 and 45 years of age weighing 140 to 200 lbs (63.3 to 90.0 kg). Subjects were given a single dose of cerivastatin 0.2 mg. After a 2-day washout period, subjects were given a loading dose of digoxin 0.5 mg for 3 days followed by 0.25 mg daily for 5 additional days (period 1-digoxin alone). Concurrent dosing with cerivastatin 0.2 mg continued for 14 days (period 2-digoxin and cerivastatin), followed by an 8-day course of digoxin-only administration and an optional 6-day extension of digoxin-only treatment for a total of 14 days (period 3). Safety was assessed through physical examination, electrocardiography, laboratory tests, and ophthalmologic examination. Ratio analyses of mean digoxin plasma trough levels, 24-hour urinary digoxin levels, and digoxin clearance with and without concurrent cerivastatin dosing also were carried out. In addition, single-dose pharmacokinetic variables for cerivastatin, including area under the curve (AUC(0-24)), peak concentration (C(max)), time to peak concentration (T(max)), and elimination half-life (t1/2), were examined with and without concurrent digoxin dosing. Eleven of the 20 subjects completed the entire study. Seven subjects discontinued the study because of treatment-emergent adverse events or laboratory abnormalities that were mostly unrelated to cerivastatin, and 2 subjects were discontinued because of protocol violations. Treatment-emergent adverse events developed in 12 subjects receiving cerivastatin; 11 of these subjects were receiving digoxin concurrently. Six adverse events that led to discontinuation of treatment were unrelated to cerivastatin but were related to digoxin or to a preexisting condition. The most commonly reported event was headache, which occurred with equal frequency compared with placebo groups in large cerivastatin clinical trials. Other events were mild or moderate and resolved without intervention. Mild and transient elevations in hepatic transaminase and creatine kinase values (all <2 times the upper limit of normal) were observed in 7 subjects. After 14 days of concurrent dosing of cerivastatin and digoxin, steady-state digoxin plasma levels, urinary digoxin levels, and urinary digoxin clearance were unchanged compared with steady-state digoxin levels when digoxin was given alone. Compared with dosing with digoxin alone, the AUC(0-24), Cmax, and t1/2 for cerivastatin increased 3%, 20%, and 7%, respectively, while the T(max) was reduced by 18% during concurrent treatment with digoxin. These changes are minimal and would not be expected to be clinically relevant. These results demonstrate that when cerivastatin is administered concurrently with digoxin, neither digoxin nor cerivastatin plasma levels are altered. The combination therapy was generally well tolerated.

Mice deficient for tenascin-R display alterations of the extracellular matrix and decreased axonal conduction velocities in the CNS

Tenascin-R (TN-R), an extracellular matrix glycoprotein of the CNS, localizes to nodes of Ranvier and perineuronal nets and interacts in vitro with other extracellular matrix components and recognition molecules of the immunoglobulin superfamily. To characterize the functional roles of TN-R in vivo, we have generated mice deficient for TN-R by homologous recombination using embryonic stem cells. TN-R-deficient mice are viable and fertile. The anatomy of all major brain areas and the formation and structure of myelin appear normal. However, immunostaining for the chondroitin sulfate proteoglycan phosphacan, a high-affinity ligand for TN-R, is weak and diffuse in the mutant when compared with wild-type mice. Compound action potential recordings from optic nerves of mutant mice show a significant decrease in conduction velocity as compared with controls. However, at nodes of Ranvier there is no apparent change in expression and distribution of Na+ channels, which are thought to bind to TN-R via their beta2 subunit. The distribution of carbohydrate epitopes of perineuronal nets recognized by the lectin Wisteria floribunda or antibodies to the HNK-1 carbohydrate on somata and dendrites of cortical and hippocampal interneurons is abnormal. These observations indicate an essential role for TN-R in the formation of perineuronal nets and in normal conduction velocity of optic nerve.

The role of vitamins in the prevention of osteoporosis--a brief status report

This papers summarizes the main role vitamins are believed to play in the prevention of osteoporosis, a common disease which is anticipated to rapidly increase because of the aging of the population. Vitamin D, the classical vitamin related to bone health, improves bone strength mainly by increasing intestinal calcium absorption and reabsorption of calcium by the kidney. Several intervention studies demonstrated in humans that vitamin D can improve bone status as measured by bone density. Vitamin C is considered an essential cofactor of collagen formation. Epidemiological studies report a positive association between vitamin C intake and bone density. Intervention studies on the effect of vitamin C on bone status are missing. Vitamin B6 could function as a cofactor to build up cross-links. In humans, however, there is little evidence to support this. Vitamin K is required for the biological activity of several coagulation factors; the classical function of vitamin K. Recent research also points to a role of vitamin K in bone metabolism. Vitamin K mediates the <--carboxylation of glutamyl residues on several bone proteins, notably osteocalcin. Epidemiological studies and results from first intervention trials are consistently suggesting that vitamin K may improve bone health.

Hereditary pancreatitis and mutation of the trypsinogen gene

Hereditary pancreatitis is a rare form of chronic recurrent pancreatitis. A family, in which 11 members had chronic pancreatitis, five had diabetes, and two had pancreatic cancer, was studied, and hereditary pancreatitis was diagnosed in all patients by demonstrating the mutation in exon 3 of the cationic trypsinogen gene (R117H). The clinical implications of genotypic analysis in hereditary pancreatitis are discussed.

[Plexiform neurofibroma and basal ganglia anomaly in Watson syndrome]

A 4 year-old boy was referred for diagnostic reevaluation with known pulmonary valve stenosis. Physical examination revealed multiple cafe-au-lait spots, inguinal freckling and on the right side in supraclavicular region a softly, non-painful tumour. The boy showed a mild mental and language retardation. Ultrasound and MRT demonstrated supraclavicular a plexiform neurofibroma and intracranial increased intensity lesions in basal ganglia and mesencephalon. In our patient, we have diagnosed a Watson-Syndrome, the overlap and differences to neurofibromatosis type I is discussed.

Purification, crystallization and preliminary crystallographic studies of a two fibronectin type-III domain segment from chicken tenascin encompassing the heparin- and contactin-binding regions

A fragment of chicken tenascin consisting of fibronectin type-III domains 5 and 6 has been expressed in Escherichia coli. After modifying a previously reported purification protocol, an electrophoretically homogeneous recombinant protein was obtained from which various crystal forms could be grown under identical conditions. Only one form was suitable for structure determination. These crystals belong to space group P21, with unit-cell parameters a = 45.2, b = 57.9, c = 72.2 A, beta = 91.4 degrees, and diffract to at least 2.6 A resolution using synchrotron radiation. From density measurements of the crystals, it was found that there are two molecules in the asymmetric unit. Diffraction data of native, two platinum-derivative and one palladium-derivative crystals were collected.

Coagulation and fibrinolysis in children, adolescents, and young adults with inflammatory bowel disease

BACKGROUND

Patients with Crohn's disease and ulcerative colitis have an increased risk of thromboembolic events.

METHODS

Data were collected from 24 patients aged 4.5 to 23 years who had inflammatory bowel disease. Platelet count, antithrombin, fibrinogen, prothrombin fragment F1+2, soluble thrombomodulin, tissue plasminogen activator, D-dimer, and plasminogen activator inhibitor-1 antigen were investigated. In addition the response to activated protein C, the factor V R506Q mutation, protein C, free protein S antigen, and lipoprotein (a) were analyzed. These data were compared with medical treatment, duration, and disease activity, estimated with the Pediatric Crohn's Disease Activity Index or the Clinical Colitis Activity Index.

RESULTS

Forty-five percent of our patients showed an increase in fibrinogen, 29% in prothrombin fragment F1+2, and 20% in platelet count, plasminogen activator inhibitor- antigen, and soluble thrombomodulin. Thrombomodulin was higher in active disease than in inactive disease and in Crohn's disease than in ulcerative colitis. Fibrinogen was also higher with Crohn's disease and tended to be higher in active disease than in ulcerative colitis and inactive disease. Plasminogen activator inhibitor-1 antigen was significantly higher in patients with Crohn's disease than in those with ulcerative colitis and was higher in the patient group treated with steroids.

CONCLUSION

As has been shown in adults, young patients with active and inactive inflammatory bowel disease were found to have abnormal coagulation and fibrinolysis. The relevance as a thromboembolic risk factor is discussed.

Immunohistochemical localization of 5-oxo-L-prolinase, an enzyme of the gamma-glutamyl cycle, in porcine brain microvessels

The immunohistochemical analysis of the distribution of 5-oxo-L-prolinase in porcine brain at the light microscopic level was performed with an antibody raised against the enzyme purified from pig kidney. The present study reveals the specific expression of 5-oxo-L-prolinase in brain capillaries with an average diameter of 4.1+/-0.9 microm, while larger blood vessels remain unstained. Porcine kidney and skeletal muscle show no endothelial-specific staining with the antibody. In some cases, the asymmetrical staining pattern in cross and longitudinal sections of brain microvessels indicate endothelial- but also pericyte-specific expression.

Kinetic parameters and tissue distribution of 5-oxo-L-prolinase determined by a fluorimetric assay

5-Oxo-L-prolinase (5-OPase) catalyses the hydrolysis of 5-oxo-L-proline to glutamate with concomitant stoichiometric cleavage of ATP to ADP, a reaction which is known to be part of the gamma-glutamyl cycle-an interrelated series of reactions involved in the synthesis and metabolism of glutathione. As recent studies indicate, this cyclic pathway plays a crucial role in the regulation of amino acid transport. Apparently, the intermediate product 5-oxo-L-proline functions as a second messenger molecule that upregulates the activity of certain amino acid transport systems. Thus, the degradation of 5-oxo-L-proline by 5-OPase leads to the downregulation of this stimulus. In this study, a new sensitive fluorimetric assay for 5-OPase activity was established which is based on the derivatization of glutamate with o-phthaldialdehyde in the presence of thiols and subsequent separation of the products by HPLC. The method is suitable for the screening of chromatography fractions as well as for the determination of the kinetic parameters Km and Vmax of purified 5-OPase. Additionally, it can be used for the measurement of enzyme activity in crude cell extracts and evaluation of tissue distribution.

Inactivation of ataxia telangiectasia mutated gene in B-cell chronic lymphocytic leukaemia

BACKGROUND

Patients with the inherited disorder ataxia telangiectasia (A-T) have an increased susceptibility to lymphoid malignancies. In these patients mutations affect both alleles of the A-T gene (ATM). We have looked for mutations in the ATM gene in sporadic cases of B-cell chronic lymphocytic leukaemia (B-CLL).

METHODS

32 cases of B-CLL were analysed by restriction endonuclease fingerprinting to detect mutations within ATM. In six of the cases in which mutations were detected in tumour samples, germline DNA was screened to assess ATM carrier status. The samples in 20 cases were also studied by western blot for abnormal expression of ATM protein.

FINDINGS

Expression of the ATM protein was impaired in eight (40%) of the 20 tumours analysed, being absent in three and decreased in five. Mutations within ATM were detected in six (18%) of the 32 patients. These point mutations, deletions, and one insertion were distributed across the coding sequence of ATM. Germline mutations, which indicate ATM carrier status, were found in two of these six patients compared with a frequency within the general population of below 1 in 200.

INTERPRETATION

Abnormal expression of ATM protein is a frequent finding in B-CLL. Although the precise function of this protein is unknown, it is thought to have a role in programmed cell death, a deficiency of which would fit with the characteristic phenotype of prolonged cell survival seen in B-CLL tumour cells. Our results also suggest that carriers of ATM mutations may be at a particular risk for the development of B-CLL and this may partly explain the known genetic susceptibility to this disease.

Reproducibility of measurements of potential doubling time of tumour cells in the multicentre National Cancer Institute protocol T92-0045

We compared the flow cytometric measurement and analysis of the potential doubling time (Tpot) between three centres involved in the National Cancer Institute (NCI) protocol T92-0045. The primary purpose was to understand and minimize the variation within the measurement. A total of 102 specimens were selected at random from patients entered into the trial. Samples were prepared, stained, run and analysed in each centre and a single set of data analysed by all three centres. Analysis of the disc data set revealed that the measurement of labelling index (LI) was robust and reproducible. The estimation of duration of S-phase (T(S)) was subject to errors of profile interpretation, particularly DNA ploidy status, and analysis. The LI dominated the variation in Tpot such that the level of final agreement, after removal of outliers and ploidy agreement, reached correlation coefficients of 0.9. The sample data showed poor agreement within each of the components of the measurement. There was some improvement when ploidy was in agreement, but correlation coefficients failed to exceed values of 0.5 for Tpot. The data suggest that observer-associated analysis of T(S) and tissue processing and tumour heterogeneity were the major causes of variability in the Tpot measurement. The first two aspects can be standardized and minimized, but heterogeneity will remain a problem with biopsy techniques.

Vitamin K intake and hip fractures in women: a prospective study

BACKGROUND

Vitamin K mediates the gamma-carboxylation of glutamyl residues on several bone proteins, notably osteocalcin. High serum concentrations of undercarboxylated osteocalcin and low serum concentrations of vitamin K are associated with lower bone mineral density and increased risk of hip fracture. However, data are limited on the effects of dietary vitamin K.

OBJECTIVE

We investigated the hypothesis that high intakes of vitamin K are associated with a lower risk of hip fracture in women.

DESIGN

We conducted a prospective analysis within the Nurses' Health Study cohort. Diet was assessed in 72327 women aged 38-63 y with a food-frequency questionnaire in 1984 (baseline). During the subsequent 10 y of follow-up, 270 hip fractures resulting from low or moderate trauma were reported.

RESULTS

Women in quintiles 2-5 of vitamin K intake had a significantly lower age-adjusted relative risk (RR: 0.70; 95% CI: 0.53, 0.93) of hip fracture than women in the lowest quintile (< 109 microg/d). Risk did not decrease between quintiles 2 and 5 and risk estimates were not altered when other risk factors for osteoporosis, including calcium and vitamin D intakes, were added to the models. Risk of hip fracture was also inversely associated with lettuce consumption (RR: 0.55; 95% CI: 0.40, 0.78) for one or more servings per day compared with one or fewer servings per week), the food that contributed the most to dietary vitamin K intakes.

CONCLUSIONS

Low intakes of vitamin K may increase the risk of hip fracture in women. The data support the suggestion for a reassessment of the vitamin K requirements that are based on bone health and blood coagulation.