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Hormone replacement therapy (HRT) in one form or another has been used for over 70 years, yet there are still disagreements regarding its clinical value and its safety. Particularly in terms of its...

The surface ectoderm is the source of ectodermal appendages including hair, teeth, and many glands. The development and function of ectodermal appendages has been researched extensively, but many of the molecular mechanisms that govern the developmental programs of ectodermal appendages remain elusive. While several protein-coding genes are established as key regulators of ectodermal appendage development, the role of noncoding RNAs is an emerging area of investigation. This review highlights recent advances in studies of microRNA-mediated control of ectodermal appendage development using mouse models. We will also discuss future directions and technological advances that will drive the microRNA field forward and expand our understanding of how individual microRNAs control ectodermal appendage development.

Amyloidosis is a malignant pathology associated with the formation of proteinaceous amyloid fibrils that deposit in organs and tissues, leading to dysfunction and severe morbidity. More than 25 proteins have been identified as components of amyloid, but the most common form of systemic amyloidosis is associated with the deposition of amyloid composed of Ig light chains (AL). Clinical management of amyloidosis focuses on reducing synthesis of the amyloid precursor protein. However, recently, passive immunotherapy using amyloid fibril-reactive antibodies, such as 11-1F4, to remove amyloid from organs has been shown to be effective at restoring organ function in patients with AL amyloidosis. However, 11-1F4 does not bind amyloid in all AL patients, as evidenced by PET/CT imaging, nor does it efficiently bind the many other forms of amyloid. To enhance the reactivity and expand the utility of the 11-1F4 mAb as an amyloid immunotherapeutic, we have developed a pretargeting "peptope" comprising a multiamyloid-reactive peptide, p5+14, fused to a high-affinity peptide epitope recognized by 11-1F4. The peptope, known as p66, bound the 11-1F4 mAb in vitro with subnanomolar efficiency, exhibited multiamyloid reactivity in vitro and, using tissue biodistribution and SPECT imaging, colocalized with amyloid deposits in a mouse model of systemic serum amyloid A amyloidosis. Pretreatment with the peptope induced 11-1F4 mAb accumulation in serum amyloid A deposits in vivo and enhanced 11-1F4-mediated dissolution of a human AL amyloid extract implanted in mice.

Cranial sutures separate the skull bones and house stem cells for bone growth and repair. In Saethre-Chotzen syndrome, mutations in TCF12 or TWIST1 ablate a specific suture, the coronal. This suture forms at a neural-crest/mesoderm interface in mammals and a mesoderm/mesoderm interface in zebrafish. Despite this difference, we show that combinatorial loss of TCF12 and TWIST1 homologs in zebrafish also results in specific loss of the coronal suture. Sequential bone staining reveals an initial, directional acceleration of bone production in the mutant skull, with subsequent localized stalling of bone growth prefiguring coronal suture loss. Mouse genetics further reveal requirements for Twist1 and Tcf12 in both the frontal and parietal bones for suture patency, and to maintain putative progenitors in the coronal region. These findings reveal conservation of coronal suture formation despite evolutionary shifts in embryonic origins, and suggest that the coronal suture might be especially susceptible to imbalances in progenitor maintenance and osteoblast differentiation., eLife digest Some of the most common birth defects involve improper development of the head and face. One such birth defect is called craniosynostosis. Normally, an infant’s skull bones are not fully fused together. Instead, they are held together by soft tissue that allows the baby’s skull to more easily pass through the birth canal. This tissue also houses specialized cells called stem cells that allow the brain and skull to grow with the child. But in craniosynostosis these stem cells behave abnormally, which fuses the skull bones together and prevents the skull and brain from growing properly during childhood. One form of craniosynostosis called Saethre-Chotzen syndrome is caused by mutations in one of two genes that ensure the proper separation of two bones in the roof of the skull. Mice with mutations in the mouse versions of these genes develop the same problem and are used to study this condition. Mouse studies have looked mostly at what happens after birth. Studies looking at what happens in embryos with these mutations could help scientists learn more. One way to do so would be to genetically engineer zebrafish with the equivalent mutations. This is because zebrafish embryos are transparent and grow outside their mother’s body, making it easier for scientists to watch them develop. Now, Teng et al. have grown zebrafish with mutations in the zebrafish versions of the genes that cause Saethre-Chotzen syndrome. In the experiments, imaging tools were used to observe the live fish as they developed. This showed that the stem cells in their skulls become abnormal much earlier than previous studies had suggested. Teng et al. also showed that similar stem cells are responsible for growth of the skull in zebrafish and mice. Babies with craniosynostosis often need multiple, risky surgeries to separate their skull bones and allow their brain and head to grow. Unfortunately, these bones often fuse again because they have abnormal stem cells. Teng et al. provide new information on what goes wrong in these stem cells. Hopefully, this new information will help scientists to one day correct the defective stem cells in babies with craniosynostosis, thus reducing the number of surgeries needed to correct the problem.

The tear producing lacrimal gland is a tubular organ that protects and lubricates the ocular surface. While the lacrimal gland possesses many features that make it an excellent model to understand tubulogenesis, the cell types and lineage relationships that drive lacrimal gland formation are unclear. Using single cell sequencing and other molecular tools, we reveal novel cell identities and epithelial lineage dynamics that underlie lacrimal gland development. We show that the lacrimal gland from its earliest developmental stages is composed of multiple subpopulations of immune, epithelial, and mesenchymal cell lineages. The epithelial lineage exhibits the most substantiative cellular changes, transitioning through a series of unique transcriptional states to become terminally differentiated acinar, ductal and myoepithelial cells. Furthermore, lineage tracing in postnatal and adult glands provides the first direct evidence of unipotent KRT5+ epithelial cells in the lacrimal gland. Finally, we show conservation of developmental markers between the developing mouse and human lacrimal gland, supporting the use of mice to understand human development. Together, our data reveal critical features of lacrimal gland development that have broad implications for understanding epithelial organogenesis.

The publication of preliminary findings from the Women's Health Initiative (WHI) Study in 2002 suggested an increased risk of breast cancer among users of menopause hormone therapy (MHT). This resulted world-wide in a rapid and significant decline in the use of hormone therapy. It was later claimed that breast cancer incidence rates had fallen as a result of lower rates of hormone therapy use. Our aim was to investigate whether there was an association between changes in the use of hormone therapy and rates of breast cancer diagnosis in New Zealand subsequent to the publication of the WHI.Validated prescription usage data along with breast cancer screening and cancer registration data were accessed. Time trends extending for 8 years after the publication of the WHI were assessed.The use of hormone therapy for managing menopausal symptoms fell by about 70% following the controversy about its safety. Breast cancer registration rates among women aged 50-59 years had started to fall in advance of this change in prescribing. Changes in other age groups appear to coincide with changes in the screening eligibility for the national breast screening program rather than use of hormone therapy.The time trend analysis does not support an association between changes in hormone therapy use and the incidence rate of breast cancer.

The NMR structure is presented for compound 1 (BMS-480404) (Ki = 33 (+/-2) nM) bound to keratinocyte fatty acid-binding protein. This article describes interactions between a high affinity drug-like compound and a member of the fatty acid-binding protein family. A benzyl group ortho to the mandelic acid in 1 occupies an area of the protein that fatty acids do not normally contact. Similar to that in the kFABP-palmitic acid structure, the acid moiety in 1 is proximal to R129 and Y131. Computational modeling indicates that the acid moiety in 1 interacts indirectly via a modeled water molecule to R109.

Adipocyte lipid-binding protein (A-LBP) and muscle fatty acid-binding protein (M-FABP) are members of a family of small ( approximately 15 kDa) cytosolic proteins that are involved in the metabolism of fatty acids and other lipid-soluble molecules. Although highly homologous (65%) and structurally very similar, A-LBP and M-FABP display distinct ligand binding characteristics. Since ligand binding may be influenced by intrinsic protein dynamical properties, we have characterized the backbone and side chain dynamics of uncomplexed (apo) human A-LBP and M-FABP. Backbone dynamics were characterized by measurements of 15N T1 and T2 values and ¿1H¿-15N NOEs. These data were analyzed using model-free spectral density functions and reduced spectral density mapping. The dynamics of methyl-containing side chains were charaterized by measurements of 2H T1 and T1rho relaxation times of 13C1H22H groups. The 2H relaxation data were analyzed using the model-free approach. For A-LBP, 15N relaxation data were obtained for 111 residues and 2H relaxation data were obtained for 42 methyl groups. For M-FABP, 15N relaxation data were obtained for 111 residues and 2H relaxation data were obtained for 53 methyl groups. The intrinsic flexibilities of these two proteins are compared, with particular emphasis placed on binding pocket residues. There are a number of distinct dynamical differences among corresponding residues between the two proteins. In particular, many residues display greater backbone picosecond to nanosecond and/or microsecond to millisecond time scale mobility in A-LBP relative to M-FABP, including F57, K58, and most residues in alpha-helix 2 (residues 28-35). Variations in the dynamics of this region may play a role in ligand selectivity. The side chains lining the fatty acid binding pocket display a wide range of motional restriction in both proteins. Side chains showing distinct dynamical differences between the two proteins include those of residues 20, 29, and 51. This information provides a necessary benchmark for determining dynamical changes induced by ligand binding and may ultimately lead to an enhanced understanding of ligand affinity and selectivity among fatty acid-binding proteins.

STUDY OBJECTIVE: To investigate whether there has been an increase of venous thromboembolism (VTE) mortality in European countries, concurrent with the replacement of second generation by third generation combined oral contraceptives (COCs). Such an increase has been predicted, and reportedly detected, because published studies have detected an increased incidence of VTE associated with third generation rather than second generation COC use. DESIGN: Data were collected on population and annual VTE mortality in women 15-34 and 35-49 years old, and on second and third generation COC sales, from 1981 to 1994 in 13 European countries. Data from the seven most populous countries were analysed by linear regression of annual VTE mortality, in the 15-34 and 15-49 age groups, with respect to calculated total and third generation COC use rates, and the regression coefficients used to estimate mortality differences between second generation users and non-users and between third and second generation users, respectively. MAIN RESULTS: The estimated mortality differences in all seven countries had confidence intervals wide enough to contain both zero and the excess mortalities expected from the results of published studies. This was true both for the mortality difference between third and second generation COC users and for that between second generation users and COC non-users. CONCLUSIONS: Mortality differences of the size expected from the published studies cannot be measured using annual national VTE mortality and COC sales data alone, because of residual interannual variation in VTE mortality, and possibly confounding between rising third generation market share and total COC use.

The protein human carbonic anhydrase II (HCA II) has been isotopically labeled with 2H, 13C and 15N for high-resolution NMR assignment studies and pulse sequence development. To increase the sensitivity of several key 1H/13C/15N triple-resonance correlation experiments, 2H has been incorporated into HCA II in order to decrease the rates of 13C and 1HN T2 relaxation. NMR quantities of protein with essentially complete aliphatic 2H incorporation have been obtained by growth of E. coli in defined media containing D2O, [1,2-13C2, 99%] sodium acetate, and [15N, 99%] ammonium chloride. Complete aliphatic deuterium enrichment is optimal for 13C and 15N backbone NMR assignment studies, since the 13C and 1HN T2 relaxation times and, therefore, sensitivity are maximized. In addition, complete aliphatic deuteration increases both resolution and sensitivity by eliminating the differential 2H isotopic shift observed for partially deuterated CHnDm moieties.

To most individuals, the concept of fitness tends to conjure up mental images of physical attributes such as muscular definition or low bodyweight. However, while physical fitness (e.g., body weight, adiposity) is an important component of overall health, there are many “unseen” physiological and biological fitness alterations to the human body that have a far-reaching impact on health and wellness. Over the years, there have been many studies investigating the physiological implications, benefits, and consequences of physical fitness [1]. There are a number of important physiological adaptations, which occur with increasing aptitude in physical fitness. These adaptations include, but are not limited to, greater cardiorespiratory capacity/efficiency, denser bone structure, higher basal metabolic rates, and lower levels of adiposity [2–4]. Furthermore, each adaptation is linked to improved mortality and reduced risk of acute and chronic illnesses. However, though mostly beneficial, these unseen physiological fitness changes may be so varied depending on the individual that they can cause challenges for healthcare providers [5, 6]. Prevention and management of disease, as well as therapeutic dosing, are directly affected by the fitness level of an individual. Therefore, defining the fitness status of an individual at a molecular level, not just by determining physical parameters of fitness, should result in better healthcare and enhanced well-being of an individual. For example, although therapeutic dosing is, in general, determined based on the total body weight of an individual, studies have demonstrated that more physically fit individuals, with more lean mass and less adiposity, can clear pharmaceuticals faster than sedentary individuals with the same total body weight [7, 8]. Dosage decision making may be better tailored to an individual's need in the future by taking into account his/her fitness level. In that regard, the availability of molecular markers of fitness should allow for more precise therapeutic dosing as compared to the traditional method of basing it on total body weight. The ability to rapidly determine the aptitude and the level of physical fitness, through molecular screening methods, has implications in many different fields, those ranging from healthcare [2, 5, 6, 9] to athletics [3] and to the military [10, 11]. To this end, it is necessary to discover and investigate molecular markers which are robust, can be observed at either elevated or lowered levels after short or prolonged exercise(s) regimes or during sedentary periods, and are accurate indicators of the physical fitness and lifestyle of an individual. Furthermore, it will also be necessary to develop point-of-care devices and corresponding analytical methods to make analysis of these molecular markers as simple and cost effective as possible. The aim of this article is to provide information that guides in the selection, detection, and future usage of molecular markers of physical fitness.

Based principally on findings in three studies, the collaborative reanalysis (CR), the Women's Health Initiative (WHI) and the Million Women Study (MWS), it is claimed that hormone replacement therapy (HRT) with estrogen plus progestogen (E+P) is now an established cause of breast cancer; the CR and MWS investigators claim that unopposed estrogen therapy (ET) also increases the risk, but to a lesser degree than does E+P. The authors have previously reviewed the findings in the CR and WHI (Parts 1-3).To evaluate the evidence for causality in the MWS.Using generally accepted causal criteria, in this article (Part 4) the authors evaluate the findings in the MWS for E+P and for ET.Despite the massive size of the MWS the findings for E+P and for ET did not adequately satisfy the criteria of time order, information bias, detection bias, confounding, statistical stability and strength of association, duration-response, internal consistency, external consistency or biological plausibility. Had detection bias resulted in the identification in women aged 50-55 years of 0.3 additional cases of breast cancer in ET users per 1000 per year, or 1.2 in E+P users, it would have nullified the apparent risks reported.HRT may or may not increase the risk of breast cancer, but the MWS did not establish that it does.

Matrix metalloproteases (MMPs) play an important role in cartilage homeostasis under both normal and inflamed disease states and, thus, have become attractive targets for the treatment of arthritic diseases. Herein, we describe the identification of a potent, selective MMP-13 inhibitor, developed using fragment-based structure-guided lead identification and optimization techniques. Virtual screening methods identified a novel, indole-based MMP-13 inhibitor that bound into the S1' pocket of the protein exhibiting a novel interaction pattern hitherto not observed in MMP-13 inhibitors. X-ray crystallographic structures were used to guide the elaboration of the fragment, ultimately leading to a potent inhibitor that was >100-fold selective over nine other MMP isoforms tested.

For the past decade patients with learning disabilities living in long stay mental handicap hospitals have been resettled in the community. Local authorities have also taken on the care of new patients who would once have been long stay residents. The imperfect data that are available suggest that in England about half the residents in mental handicap hospitals in 1981 are now the responsibility of local authorities; the figures for Wales and Northern Ireland are 38% and 33%. Data on revenue suggest that the savings to the health service are much less--perhaps 9% in Northern Ireland and 3.6% in England, although there have also been capital gains through the sale of hospitals. Existing methods of transferring money from health to local authorities--joint finance and "dowries" for individual patients--do not seem adequately to have compensated local authorities. Moreover, as patients still to be transferred are more severely disabled local authorities will require larger sums--about 26 000 pounds per patient per year plus 39 200 pounds in capital. If the government chooses not to transfer these resources from health authorities it will be switching funds away from learning disabled people to other care groups.

A direct reading X-ray intensity meter comprising a small thimble chamber on the end of a flexible cable, and measuring dose rates of 1 to 50 r per min. with a rapid response, is described. A large degree of negative feed-back is used to stabilise against changes in valves and supply voltages, and gives a precision measuring device with a linear response to radiation intensity. Circuit details are given, and it is explained how, by simple switching, the instrument may be used to measure also small doses of X rays, such as occur in diagnostic work. The cost is not great, and the general design appears to lend itself to other problems where it is necessary to measure small voltages either of a constant or slowly varying character.

Suicide is a problem experienced by railway networks worldwide. The epidemiology of this method of suicide has not been described in any detail. To investigate the characteristic features of railway suicide, data were gathered from 23 metro systems around the world. The similarities in the nature of this problem across systems were striking. Universally the victims were young (aged less than 40 years); most incidents involved men; case fatality was generally less than 60%; there was no consistent seasonal variation in incidence; the peak time of day for incidents was 1000-1200; proximity to psychiatric institutions was possibly a risk factor. This method of suicide may be prevented by environmental modification of the railway system. Strategies for reducing the opportunities for suicide on railways are discussed.

A 3D optimized, refocused HNCA experiment is described. It is demonstrated to yield a dramatic increase in sensitivity when applied to [13C, 15N]-labeled human carbonic anhydrase II, a 29-kDa protein. The reasons for the gain in sensitivity are discussed, and 3 distinct areas for further development are indicated.

OBJECTIVE--To study early and late mortality after surgical correction of coarctation of the aorta. DESIGN--Data on 223 patients operated on at the Westminster Hospital, London, between 1946 and 1981, were collected and updated by questionnaire. PARTICIPANTS--All 223 patients recorded as undergoing operation for aortic coarctation up to the end of 1981. Fifteen of 197 survivors were lost to follow up; most of them were patients from overseas. OUTCOME AND RESULTS--The early mortality (within one month of operation) was 12% overall, 2.6% for elective surgery, and 0% for the 77 patients undergoing surgery since 1968. Survivors were followed up for a total of 3288 patient years; in 27 follow up lasted more than 30 years. In a few it reached 40 years. Twenty two patients died during this period, 18 from causes that could be attributed to coarctation or its repair. Mortality was highest more than 20 years after the operation. CONCLUSION--Repair increased life expectancy in patients with aortic coarctation. Late problems caused by persistent hypertension or recoarctation became apparent in long term survivors. The increased risk of late mortality associated with the duration of preoperative hypertension was not statistically significant. There were no deaths from cerebrovascular accidents. (In an earlier necropsy series cerebrovascular accidents accounted for 11.8% of deaths.) The incidence of deaths from aneurysms resembled that in the earlier necropsy series.

STUDY OBJECTIVE--The aim was to evaluate the current approach to forecasting hospital bed requirements. DESIGN--The study was a time series and regression analysis. The time series for mean duration of stay for general surgery in the age group 15-44 years (1969-1982) was used in the evaluation of different methods of forecasting future values of mean duration of stay and its subsequent use in the formation of hospital bed requirements. RESULTS--It has been suggested that the simple trend fitting approach suffers from model specification error and imposes unjustified restrictions on the data. Time series approach (Box-Jenkins method) was shown to be a more appropriate way of modelling the data. CONCLUSION--The simple trend fitting approach is inferior to the time series approach in modelling hospital bed requirements.

p38 MAPK and MAPK-activated protein kinase 2 (MK2) are key components of signaling pathways leading to many cellular responses, notably the proinflammatory cytokine production. The physical association of p38alpha isoform and MK2 is believed to be physiologically important for this signaling. We report the 2.7-A resolution crystal structure of the unphosphorylated complex between p38alpha and MK2. These protein kinases bind "head-to-head," present their respective active sites on approximately the same side of the heterodimer, and form extensive intermolecular interactions. Among these interactions, the MK2 Ile-366-Ala-390, which includes the bipartite nuclear localization signal, binds to the p38alpha-docking region. This binding supports the involvement of noncatalytic regions to the tight binding of the MK2:p38alpha binary assembly. The MK2 residues 345-365, containing the nuclear export signal, block access to the p38alpha active site. Some regulatory phosphorylation regions of both protein kinases engage in multiple interactions with one another in this complex. This structure gives new insights into the regulation of the protein kinases p38alpha and MK2, aids in the better understanding of their known cellular and biochemical studies, and provides a basis for understanding other regulatory protein-protein interactions involving signal transduction proteins.

Pim-1 kinase is a member of a distinct class of serine/threonine kinases consisting of Pim-1, Pim-2, and Pim-3. Pim kinases are highly homologous to one another and share a unique consensus hinge region sequence, ER-PXPX, with its two proline residues separated by a non-conserved residue, but they (Pim kinases) have30% sequence identity with other kinases. Pim-1 has been implicated in both cytokine-induced signal transduction and the development of lymphoid malignancies. We have determined the crystal structures of apo Pim-1 kinase and its AMP-PNP (5'-adenylyl-beta,gamma-imidodiphosphate) complex to 2.1-angstroms resolutions. The structures reveal the following. 1) The kinase adopts a constitutively active conformation, and extensive hydrophobic and hydrogen bond interactions between the activation loop and the catalytic loop might be the structural basis for maintaining such a conformation. 2) The hinge region has a novel architecture and hydrogen-bonding pattern, which not only expand the ATP pocket but also serve to establish unambiguously the alignment of the Pim-1 hinge region with that of other kinases. 3) The binding mode of AMP-PNP to Pim-1 kinase is unique and does not involve a critical hinge region hydrogen bond interaction. Analysis of the reported Pim-1 kinase-domain structures leads to a hypothesis as to how Pim kinase activity might be regulated in vivo.

Pim kinases, including Pim-1, Pim-2 and Pim-3, belong to a distinctive serine/threonine protein-kinase family. They are involved in cytokine-induced signal transduction and the development of lymphoid malignancies. Their kinase domains are highly homologous to one another, but share low sequence identity to other kinases. Specifically, there are two proline residues in the conserved hinge-region sequence ERPXPX separated by a residue that is non-conserved among Pim kinases. Full-length human Pim-1 kinase (1-313) was cloned and expressed in Escherichia coli as a GST-fusion protein and truncated to Pim-1 (14-313) by thrombin digestion during purification. The Pim-1 (14-313) protein was purified to high homogeneity and monodispersity. This protein preparation yielded small crystals in the initial screening and large crystals after optimization. The large crystals of apo Pim-1 enzyme diffracted to 2.1 A resolution and belong to space group P6(5), with unit-cell parameters a = b = 95.9, c = 80.0 A, beta = 120 degrees and one molecule per asymmetric unit.

Perdeuteration of all non-exchangeable proton sites can significantly increase the size of proteins and protein complexes for which NMR resonance assignments and structural studies are possible. Backbone 1H, 15N, 13CO, 13C alpha and 13C beta chemical shifts and aliphatic side-chain 13C and 1H(N)/15N chemical shifts for human carbonic anhydrase II (HCA II), a 259 residue 29 kDa metalloenzyme, have been determined using a strategy based on 2D, 3D and 4D heteronuclear NMR experiments, and on perdeuterated 13C/15N-labeled protein. To date, HCA II is one of the largest monomeric proteins studied in detail by high-resolution NMR. Of the backbone resonances, 85% have been assigned using fully protonated 15N and 3C/15N-labeled protein in conjunction with established procedures based on now standard 2D and 3D NMR experiments. HCA II has been perdeuterated both to complete the backbone resonance assignment and to assign the aliphatic side-chain 13C and 1H(N)/15N resonances. The incorporation of 2H into HCA II dramatically decreases the rate of 13C and 1H(N)T2 relaxation. This, in turn, increases the sensitivity of several key 1H/13C/15N triple-resonance correlation experiments. Many otherwise marginal heteronuclear 3D and 4D correlation experiments, which are important to the assignment strategy detailed herein, can now be executed successfully on HCA II. Further analysis suggests that, from the perspective of sensitivity, perdeuteration should allow other proteins with rotational correlation times significantly longer than HCA II (tau c = 11.4 ns) to be studied successfully with these experiments. Two different protocols have been used to characterize the secondary structure of HCA II from backbone chemical-shift data. Secondary structural elements determined in this manner compare favorably with those elements determined from a consensus analysis of the HCA II crystal structure. Finally, having outlined a general strategy for assigning backbone and side-chain resonances in a perdeuterated large protein, we propose a strategy whereby this information can be used to glean more detailed structural information from the partially or fully protonated protein equivalent.

1. In view of the importance of 5-hydroxytryptamine in coronary thrombosis, we wanted to know whether a potentially protective decrease in platelet 5-hydroxytryptamine could be achieved by treatment with an inhibitor of 5-hydroxytryptamine uptake, fluoxetine. 2. We studied 15 patients treated for psychiatric indications with fluoxetine, and compared the findings with those obtained with blood from 18 patients treated with amitriptyline and 13 controls previously treated for affective disorders. 3. Platelet-rich plasma 5-hydroxytryptamine levels were significantly decreased in the fluoxetine group (P > 0.005) but not in the amitriptyline group compared with the control group. 4. Collagen-induced aggregation in whole blood anti-coagulated with hirudin was measured by sequential single platelet counting. The contribution of 5-hydroxytryptamine was assessed from the effect of adding the 5-hydroxytryptamine specific antagonist ICI 170809. This contribution was significantly decreased in the fluoxetine group but not in the amitriptyline group compared with the control group. 5. It is concluded that platelet 5-hydroxytryptamine is indeed decreased by fluoxetine, and we would predict a protective effect of fluoxetine against coronary thrombosis.

Profilin is a ubiquitous eukaryotic protein that binds to both cytosolic actin and the phospholipid phosphatidylinositol-4,5-bisphosphate. These dual competitive binding capabilities of profilin suggest that profilin serves as a link between the phosphatidyl inositol cycle and actin polymerization, and thus profilin may be an essential component in the signaling pathway leading to cytoskeletal rearrangement. The refined three-dimensional solution structure of human profilin I has been determined using multidimensional heteronuclear NMR spectroscopy. Twenty structures were selected to represent the solution conformational ensemble. This ensemble of structures has root-mean-square distance deviations from the mean structure of 0.58 A for the backbone atoms and 0.98 A for all non-hydrogen atoms. Comparison of the solution structure of human profilin to the crystal structure of bovine profilin reveals that, although profilin adopts essentially identical conformations in both states, the solution structure is more compact than the crystal structure. Interestingly, the regions that show the most structural diversity are located at or near the actin-binding site of profilin. We suggest that structural differences are reflective of dynamical properties of profilin that facilitate favorable interactions with actin. The global folding pattern of human profilin also closely resembles that of Acanthamoeba profilin I, reflective of the 22% sequence identity and approximately 45% sequence similarity between these two proteins.

Around 90 London Underground train drivers experience a person jumping or falling in front of their train each year. The majority of these incidents are suicides or attempted suicides. 76 drivers were interviewed in order to assess the range of responses to these incidents. The following psychometric instruments were used: Present State Examination (PSE9); Post-Traumatic Stress Disorder (PTSD) Interview; General Health Questionnaire (GHQ-28); Impact of Events Scale (IES); Post-Traumatic Symptom Scale; Recent Difficulties/Events scale; Perceived Stress Scale and Eysenck Personality Questionnaire (EPQ). When interviewed 1 month after the incident 13 (17.11%) drivers presented with PTSD. Diagnoses other than PTSD e.g. neurotic depression and phobic state were present in 24 (31.58%) drivers (including 12 of the 13 PTSD cases who had one additional diagnosis). On the basis of diagnoses three groups were identified: Group 1 drivers had PTSD and in most cases an additional PSE9 diagnosis; Group 2 drivers had a PSE9 diagnosis only; Group 3 drivers were not cases. 56 drivers were again interviewed 6 months after the incident to assess duration of caseness and/or symptoms and to identify any cases of delayed onset. Two drivers were still cases at 6 months (neurotic depression and phobic state), no driver presented with PTSD at 6 months. At 6 months there was a significant drop in symptom scores compared with measures taken at 1 month. These results suggest that although approximately one-third of drivers suffered a severe psychological reaction following a railway suicide, when interviewed again 6 months after the incident most drivers reported a marked reduction in symptoms.

A database containing details of every incident of suicidal behaviour on the London Underground railway system between 1940 and 1990 was assembled from the records of London Underground Ltd and the British Transport Police. The total number of cases was 3240. The mean annual number of suicidal acts on the London Underground system increased from 36.1 (1940-1949) to 94.1 (1980-1989). There were significantly fewer incidents on Sundays than on the other days of the week and the daily rate was highest in the spring. 64% of incidents involved males and the peak age group for both sexes was 25-34 yr. Suicide verdicts were returned for a greater proportion of women than men. Overall case fatality was 55%. However, case fatality rates differed between stations, environmental factors appearing to influence survival. Possible strategies to prevent railway suicides and reduce the lethality of this method are discussed.

Views about ways of telling parents their child has a mental handicap were collected from a group of parents of children with mental handicaps and a group of doctors with some involvement in this field, using postal questionnaires. Four Likerttype scales were refined covering views about the fullness of information, how early parents should be told, whether parents should be protected from shock and unpleasant information, and who should take a primary role in decision-making. Results indicated that parents were more in favour of being given information about their children's handicaps at an early stage than doctors were, and that they saw themselves as the primary decision-makers in matters to do with their children, whilst doctors were more neutral about this. There were no differences in how parents and doctors felt about the fullness of explanations or about the explicit‘protection’of parents from shock and unpleasant information. The results support the findings of other studies which have stressed parents’wishes to be given as much information as early as possible and to be treated as the people primarily responsible for their child. In addition, a difference between what doctors believe to be the best approach and what parents believe to be the best approach is suggested, and the importance of doctors being given opportunities to learn directly from parents and people with mental handicaps themselves is emphasized.

The attitudes to people with mental handicaps held by a group of parents of children with mental handicaps and a group of doctors with some involvement in this area were compared using postal questionnaires. Doctors' estimates of how parents would respond were also compared with parents' responses and doctors' own responses. Four Likert-type scales were refined covering attitudes towards the effect on the family, the place in society of people with mental handicaps, their quality of life, and independence and autonomy. Results indicated that parents had more positive attitudes than doctors except with regard to independence and autonomy, to which doctors had the most positive attitudes. Doctors were aware that parents were likely to see the effect on the family in a more positive light, and independence less positively, than themselves. However, they underestimated the degree of positivity of parents about the place of people with mental handicaps in society, and their quality of life, to the extent that they expected parents to be significantly less positive about quality of life than they themselves were, whilst parents in fact proved significantly more positive. The differing perspectives and experiences of parents and doctors are discussed and some suggestions made of ways in which doctors' appreciation of the parental perspective could be developed in an attempt to facilitate sympathetic communication between them.

Resume Trente-quatre patients qui avaient consulte leur medecin generaliste cinq fois ou plus pendant une periode de trois mois ont ete compares avec trente-quatre personnes qui ne l'avaient consulte qu'une fois pendant la meme periode. On les a compares selon l'âge et le sexe en utilisant des criteres psychosomatiques. Les tests utilises pour cette etude etaient le Questionnaire sur la Sante Generale, l'Inventaire de la Personnalite d'Eysenck (EPI) et le Differenciateur Semantique. Les sujets a consultations frequentes obtenaient le plus de points avec le Questionnaire sur la Sante Generale et avec l'EPI et le differenciateur semantique revelait des differences majeures dans l'attitude a l'egard de la sante, de l'aide, de soi et des medecins. Ces differences pouvaient etre la cause de la frequence des consultations ou, aussi, etre causees par elle.

Previous work (see ibid., vol.16, 577) has been continued to determine the practical capabilities of the system. A higher resolution Ge(Li) detector has been used to portray the scattering along the lines of passage of a 137Cs gamma -ray beam, and from these results it is possible to construct density cross-sections of the body. The limitations are shown to be due to (a) signal/noise arising from multiple scattering in the body and (b) resolution, which is governed by the finite beam width and finite aperture needed in front of the crystal. A suggested design of a twin-headed machine for clinical use is given.

SynopsisThe variations in suicide mortality in England and Wales over a 100-year period (1876–1975) are explained by the development of a descriptive model. The model used is a stepwise linear regression using 5 variables including toxic gas production. The variables give a good description of the observed changes in suicide mortality. The limitations of the method and the data are discussed. Despite the limitations of the method, it can be concluded that toxic gas production affected total suicide mortality.

Quinolinic acid (2,3-pyridinedicarboxylic acid), an endogenous metabolite of L-tryptophan, reportedly via the kynurenine pathway, has been previously shown to possess neurotoxic properties when injected into rat striatum (Schwarcz, R., Whetsell, W.O., Jr. and Mangano, R.M. (1983) Science 219, 316-318) and to alter the physical state of human erythrocyte membrane proteins, as judged by ESR spectroscopy (Farmer, B.T., II and Butterfield, D.A. (1984) Life Sci. 35, 501-509). Both the morphologic and ESR studies employed nicotinic acid as one comparative control and found that the effect of quinolinic acid is significantly different from that of nicotinic acid. In the present study, we report that the effects of several structural analogues and positional isomers of quinolinic acid on the ESR parameter associated with the physical state of membrane proteins in human erythrocyte membranes suggest the following conclusions concerning the structure-effect relationship of quinolinic acid: The alteration in the conformation of membrane proteins: (1) requires the presence of two carboxylic acid groups; (2) is independent of their relationship to one another on the pyridine ring; (3) is slightly dependent on the presence of the pyridine nitrogen atom but is independent of the positional relationship of the two carboxylic acid moieties to the heteroatom; and (4) seems to depend upon the presence of restricted internal motion derived from the aromaticity in these compounds.

Age specific death rates for poisoning with different antidepressant drugs, based on mortality statistics and the numbers of prescriptions dispensed, were calculated for England and Wales 1979-1985. There are marked variations in mortality associated with different drugs; the highest rates are found with amitriptyline and dothiepin whereas the lowest were associated with mianserin and clomipramine. For all drugs considered, the calculated mortality rates for the over 65 year olds, though still substantial, were lower than those in patients under 65 years of age, probably because of a diminished detection rate of poisoning in this older age group. A high proportion of the fatal overdoses implicating amitriptyline and dothiepin involved more than one substance. The rank order of mortality rates from antidepressants was identical in the different age groups. The implications of these findings are discussed. It is concluded that the variations in mortality rates are mostly due to variations in the inherent toxicity of the drugs (particularly their cardiovascular effects) and only in part due to possible differences in compliance. It is suggested that when antidepressant drugs are prescribed, the risk of death from overdose should be taken into account. Tricyclic drugs, particularly amitriptyline, dothiepin, doxepin, trimipramine and maprotiline, should be avoided in patients at risk of suicide, whatever the age of the patient.

Quinolinic acid (2,3-pyridinedicarboxylic acid), an endogenous, tryptophan metabolite, is neurotoxic when injected into rat striatum (1). To begin to investigate the molecular interactions of quinolinic acid with membranes, electron spin resonance studies of the effects of this neurotoxin on the physical state of lipids, proteins, and cell-surface sialic acid in human erythrocyte ghosts have been performed. Quinolinic acid induced a highly significant alteration in the physical state of membrane proteins (P less than 0.01) while that of sialic acid and membrane lipids was unaffected. These results are similar to those induced by ibotenic acid, an exogenous neurotoxin, and are discussed with reference to possible molecular characteristics of the interaction of these neurotoxins with membrane proteins.

A method to selectively spin label galactose and N -acetylgalactosamine residues of erythrocyte membrane glycoconjugates is described. The method is based on the activation of the C-6 CH 2 OH group of these two sugars by galactose oxidase followed by reductive amination with 2,2,6,6-tetramethyl-4-aminopiperidine-1-oxyl in the presence of a mild reducing agent, NaBH 3 CN. The extent and distribution of the spin labeling suggest that the major sialoglycoprotein, PAS-1, incorporates the greatest amount of spin label while the glycolipids incorporate less than `0% of the spin label.

Summary The annual numbers of suicide deaths for the past 100 years by different methods in England and Wales are presented. It is shown that the numbers of deaths by 2 methods, domestic gas poisoning and poisoning by solid or liquid substances, vary independently of all other methods. It is concluded that inferences as to cause drawn from aggregated data should be viewed with great caution.

The problem of viewing the emergent ray image from a Treatment Planning Simulator is met by the use of xeroradiography. With this a finished picture is obtained within 10 seconds of completion of the X-ray exposure, which may be studied as a basis of further beam adjustment, or photographed if desired. This technique has the advantage over film, not only of speed in processing, but of showing soft tissue detail, bone detail, air passages and skin outline, all within the same X-ray exposure range. The Simulator at Newcastle on Tyne is described and illustrations of its use in relation to the 4 MeV linear accelerator are given.

Current methods of determining anatomical cross-sections of the body for cancer treatment planning including transaxial tomography have severe limitations and a new method is described depending on the change of wavelength of gamma -rays in Compton scattering. A narrow beam of 137Cs gamma -rays is passed through the body, and the scattered radiation is picked up and analysed by a Ge(Li) detector so that the intensity is portrayed against distance through the body. The primary beam is moved slowly to traverse the whole cross-sectional area and the density pattern so obtained displayed on a cathode ray screen. Problems including limitations of resolution and attenuation of the primary and secondary radiation are studied, and an experimental arrangement, which it is hoped will lead to a practical working system, is described.

1. Three patients with myelomatosis were given intravenous 177Lu. 2. The 177Lu was shown to be taken up by the bones and concentrated around the lesions. 3. None of the patients was clinically improved by treatment with this isotope.

A comprehensive series of measurements in water phantoms has been made for arc therapy at 250 kV. The dosage distributions have been critically compared with established fixed-field techniques at 250 kV and at supervoltage. The integral doses and skin doses given by these methods are summarised for comparable treatments of the bladder. It is shown to be difficult to obtain such good physical distributions with arc methods as with well-planned fixed fields, and flattening filters and “overlap” of the anterior and posterior arcs are necessary. Where integral dose is a limiting factor, arc methods are generally inferior to fixed fields. Further, the physical distributions of corresponding supervoltage treatments are shown to be greatly superior to stationary or moving fields at 250 kV.

An instrument is described which keeps the output of an X-ray therapy tube constant within 1 or 2 per cent. over long periods. The current from an ionization chamber in the tube aperture is amplified and used to operate a relay which controls a regulating transformer in the main power supply line and so corrects variations of output in either direction. Automatic return of the transformer tapping to its mid point, on switching off the X-ray unit, is incorporated.

Suicide mortality in the area now administered by the Greater London Council was assessed for three five-year periods 1949-1953, 1959-63, and 1969-73. For each of the periods the standard mortality ratio (SMR) for suicide in various boroughs was calculated for men and women separately. The boroughs with high SMRs for men were constant. There was a pronounced change in the geographical distribution of high mortality among women. These findings support the hypothesis that the determinants of suicide differ between the sexes.

Suicide is a rare phenomenon – in most countries, it explains between 0.5 and 1% of all deaths – no more than 15 per 100 000 population. Although rates increase with age, its impact on the total mortality of the young is greater than its impact on the elderly. Despite its rarity, the subject has attracted, and continues to attract, wide interest among academics and popular writers.

During the last 40 years, with close collaboration between the physicist and medical staff, instrumentation in medicine has advanced enormously. The possibility of such advance depended on two major developments in basic science. The first was the emergence of electronics. Until the early 1940s the word electronics was scarcely known. Now this has become a vast field of technological progress. The second was the impact of solid state physics, which made its mark at about the same time. The developments that have taken place during the succeeding decades have derived very largely from these two new sources. The developments may be divided broadly into four stages, each corresponding roughly to one of the four decades considered. These stages involve valves, transistors, integrated circuits and instrumentation systems.

A method is described of displaying information about the range of multiple disabilities experienced by individuals who are also mentally handicapped, using the assesments available on a Mental Handicap Register. The presentation, in the graphical form suggested, enables groups to be compared whilst retaining details of an individual's problems.