Diamondites: evidence for a distinct tectono-thermal diamond-forming event beneath the Kaapvaal craton.

The petrogenesis and relationship of diamondite to well-studied monocrystalline and fibrous diamonds are poorly understood yet would potentially reveal new aspects of how diamond-forming fluids are transported through the lithosphere and equilibrate with surrounding silicates. Of 22 silicate- and oxide-bearing diamondites investigated, most yielded garnet intergrowths (n = 15) with major element geochemistry (i.e. Ca-Cr) classifying these samples as low-Ca websteritic or eclogitic. The garnet REE patterns fit an equilibrium model suggesting the diamond-forming fluid shares an affinity with high-density fluids (HDF) observed in fibrous diamonds, specifically on the join between the saline-carbonate end-members. The δ13C values for the diamonds range from - 5.27 to - 22.48‰ (V-PDB) with δ18O values for websteritic garnets ranging from + 7.6 to + 5.9‰ (V-SMOW). The combined C-O stable isotope data support a model for a hydrothermally altered and organic carbon-bearing subducted crustal source(s) for the diamond- and garnet-forming media. The nitrogen aggregation states of the diamonds require that diamondite-formation event(s) pre-dates fibrous diamond-formation and post-dates most of the gem monocrystalline diamond-formation events at Orapa. The modelled fluid compositions responsible for the precipitation of diamondites match the fluid-poor and fluid-rich (fibrous) monocrystalline diamonds, where all grow from HDFs within the saline-silicic-carbonatitic ternary system. However, while the nature of the parental fluid(s) share a common lithophile element geochemical affinity, the origin(s) of the saline, silicic, and/or carbonatitic components of these HDFs do not always share a common origin. Therefore, it is wholly conceivable that the diamondites are evidence of a distinct and temporally unconstrained tectono-thermal diamond-forming event beneath the Kaapvaal craton.

Comparative proteomic profiling of the ovine and human PBMC inflammatory response.

Understanding the cellular and molecular mechanisms of inflammation requires robust animal models. Sheep are commonly used in immune-related studies, yet the validity of sheep as animal models for immune and inflammatory diseases remains to be established. This cross-species comparative study analyzed the in vitro inflammatory response of ovine (oPBMCs) and human PBMCs (hPBMCs) using mass spectrometry, profiling the proteome of the secretome and whole cell lysate. Of the entire cell lysate proteome (oPBMCs: 4217, hPBMCs: 4574 proteins) 47.8% and in the secretome proteome (oPBMCs: 1913, hPBMCs: 1375 proteins) 32.8% were orthologous between species, among them 32 orthologous CD antigens, indicating the presence of six immune cell subsets. Following inflammatory stimulation, 71 proteins in oPBMCs and 176 in hPBMCs showed differential abundance, with only 7 overlapping. Network and Gene Ontology analyses identified 16 shared inflammatory-related terms and 17 canonical pathways with similar activation/inhibition patterns in both species, demonstrating significant conservation in specific immune and inflammatory responses. However, ovine PMBCs also contained a unique WC1+γδ T-cell subset, not detected in hPBMCs. Furthermore, differences in the activation/inhibition trends of seven canonical pathways and the sets of DAPs between sheep and humans, emphasize the need to consider interspecies differences in translational studies and inflammation research.

A novel magnet-based scratch method for standardisation of wound-healing assays.

A novel magnetic scratch method achieves repeatability, reproducibility and geometric control greater than pipette scratch assays and closely approximating the precision of cell exclusion assays while inducing the cell injury inherently necessary for wound healing assays. The magnetic scratch is affordable, easily implemented and standardisable and thus may contribute toward better comparability of data generated in different studies and laboratories.

Sulfide resorption during crustal ascent and degassing of oceanic plateau basalts.

Mantle plume-related magmas typically have higher chalcophile and siderophile element (CSE) contents than mid-ocean ridge basalts (MORB). These differences are often attributed to sulfide-under-saturation of plume-related melts. However, because of eruption-related degassing of sulfur (S) and the compositional, pressure, temperature and redox effects on S-solubility, understanding the magmatic behavior of S is challenging. Using CSE data for oceanic plateau basalts (OPB), which rarely degas S, we show that many OPB are sulfide-saturated. Differences in the timing of sulfide-saturation between individual OPB suites can be explained by pressure effects on sulfur solubility associated with ascent through over-thickened crust. Importantly, where S-degassing does occur, OPB have higher CSE contents than S-undegassed melts at similar stages of differentiation. This can be explained by resorption of earlier-formed sulfides, which might play an important role in enriching degassed melts in sulfide-compatible CSE and potentially contributes to anomalous enrichments of CSE in the crust.

Microfluidic nutrient gradient-based three-dimensional chondrocyte culture-on-a-chip as an in vitro equine arthritis model.

In this work, we describe a microfluidic three-dimensional (3D) chondrocyte culture mimicking in vivo articular chondrocyte morphology, cell distribution, metabolism, and gene expression. This has been accomplished by establishing a physiologic nutrient diffusion gradient across the simulated matrix, while geometric design constraints of the microchambers drive native-like cellular behavior. Primary equine chondrocytes remained viable for the extended culture time of 3 weeks and maintained the low metabolic activity and high Sox9, aggrecan, and Col2 expression typical of articular chondrocytes. Our microfluidic 3D chondrocyte microtissues were further exposed to inflammatory cytokines to establish an animal-free, in vitro osteoarthritis model. Results of our study indicate that our microtissue model emulates the basic characteristics of native cartilage and responds to biochemical injury, thus providing a new foundation for exploration of osteoarthritis pathophysiology in both human and veterinary patients.

Scapulohumeral osteochondrosis. A retrospective study of 32 horses.

OBJECTIVES: To review the outcome of equine shoulder osteochondrosis (OC) with surgical or conservative treatment. METHODS: Retrospective study of 32 horses, less than two years of age, with scapulohumeral joint (SHJ) OC. The lesion severity was graded based on measurements taken from lateromedial radiographs. Follow-up information was obtained from racing records or telephone conversations with owners. Successful outcome was defined as the ability of the horse to perform its intended use. RESULTS: Sixteen of 32 horses were affected bilaterally (48 joints). Eleven of 16 horses with bilateral OC underwent arthroscopic surgery; five had bilateral arthroscopy, six had unilateral arthroscopy of the most severely affected joint. Eight of 16 horses with unilateral OC underwent arthroscopy. The overall outcome was 'poor'. Only 15.4% (4/26) of potential race horses started a race, whereas 67% (4/6) non-racehorses were 'sound' for the intended use. Statistical analysis evaluating the effect of breed on outcome showed a statistically significant difference. There were no significant interactions between outcome and gender, affected limb, unilateral versus bilateral involvement, treatment or severity of the radiographic lesion. However, radiographic lesion severity on the humerus and glenoid showed significant positive correlation. CLINICAL SIGNIFICANCE: The overall poor prognosis for shoulder OC in young horses appears to be, in part, dependent on breed and intended use. There was not any difference in outcome between surgically and conservatively treated horses.

The embryogenesis of the equine femorotibial joint: The equine interzone.

REASONS FOR PERFORMING STUDY: Articular cartilage regeneration is the focus and goal of considerable research effort. Since articular chondrocytes descend from a distinct cohort of progenitor cells located in embryonic nascent joints (interzones), establishing the timing of equine interzone formation is an essential first step towards understanding equine joint and articular cartilage development. OBJECTIVES: To establish the time frame during which the equine femorotibial interzone forms. STUDY DESIGN: Descriptive anatomical study. METHODS: Equine embryos were harvested at 37 (E37), 40, 42, 45, 50 and 65 days' gestation. The femorotibial interzone was examined using high-resolution episcopic microscopy of E37, E42, E45, E50 and E65. Additional histology and collagen-II-immunohistochemistry were performed on E42. RESULTS: At E37, the femorotibial interzone is first visible as a uniform layer, while at E42 the interzone is fully formed and consists of 3 morphologically distinct layers. The first evidence of cavitation was seen at E45. At E50, the cruciate ligaments were well formed and by E65, joint formation appeared complete. CONCLUSIONS: The embryogenesis of the equine femorotibial joint is similar to the developmental timeline of stage-matched human and murine embryos. Further studies looking at interzone formation on a cellular and molecular level may further our understanding of the intricate developmental patterns and pathways of articular cartilage development.

The effects of lithium ions on the antidiuretic action of vasopressin in the rat.

1 The effect of intravenous infusion of lithium, 2.56 mumol/min on the antidiuretic responses to antidiuretic hormone (ADH), adenosine triphosphate (ATP), 3'-5' adenosine cylic monophosphate (cyclic AMP) and theophyline was studied in water-loaded, alcohol-anaesthetized rats. 2 Lithium reversibly inhibits the antidiuretic response to all concentrations of ADH, depressing the maximum response but not changing the amount required for half maximal response. 3 The rate of increase of serum lithium relates more clearly to the inhibitory effect than does the serum concentration. 4 Sodium concentrations in the renal papilla seem to fall when serum lithium levels are rising. 5 Lithium inhibits the antidiuretic response to ATP and cyclic AMP but does not inhibit the response to theophyline.

The effect of lithium and related metal ions on the urinary excretion of 2-oxoglutarate and citrate in the rat.

1 Administration of lithium ions to rats, either acutely by intraperitoneal injection or chronically in food, causes increased excretion of 2-oxoglutarate and citrate.2 Chronic administration in food of rubidium and caesium causes decreased excretion of 2-oxoglutarate and citrate.3 The effects described are not due to changes in urine volume, nor pH, nor are they simply related to the excretion of the injected ion.4 Acute administration of lithium caused an increased level of 2-oxoglutarate in kidney and reduced the ratio of glutamate to 2-oxoglutarate.5 Renal gluconeogenesis in slices was only slightly affected by either acute administration of lithium to the animals or by its presence in the incubation medium of renal slices.

Some aspects of the inhibition of the action of antidiuretic hormone by lithium ions in the rat kidney and bladder of the toad Bufo marinus.

1. The effect of intravenous infusions of various ions on the antidiuretic action of antidiuretic hormone has been studied in rats.2. Lithium (13 mmol/l.) reversibly inhibits the antidiuretic responses. Similar concentrations of potassium, rubidium, strontium, magnesium, choline and calcium do not. Lithium has a similar effect on the antidiuretic activity of oxytocin.3. The inhibition is not simply related to blood nor whole body lithium concentrations.4. Lithium (2 mmol/l.) in contact with the serosal surface also inhibits the transport of water facilitated by either 0.5 U/l. antidiuretic hormone or 1.1 mmol/l. cyclic adenosine monophosphate in the isolated toad bladder.5. Choline (2 mmol/l.) on the serosal surface also inhibits the transport of water facilitated by vasopressin in the toad bladder.

The distribution of lithium and its effects on the distribution and excretion of other ions in the rat.

1. In rats, lithium (ca 1 mEquiv/kg body weight) decreased brain sodium and magnesium, bone sodium and calcium and increased muscle calcium, plasma magnesium, urinary calcium and urine volume.2. Lithium was particularly concentrated in bone.

The effect of lithium salts on the urinary excretion of -oxoglutarate in man.

1. Lithium ions in therapeutic doses cause an increase in the renal excretion of alpha-oxoglutarate and glutaric acid.2. The excretion is probably due to reduced renal tubular reabsorption.3. Neither citrate, lactate nor pyruvate excretion rises.

Electrolyte metabolism in patients with periodic affective disorders during treatment with rubidium.

Five patients suffering from periodic affective disorders with short mood-cycles were treated with rubidium chloride, producing peak erythrocyte concentrations between 9 and 13 mmol/l. Loading with rubidium was associated with decreased total body potassium, but red-cell potassium was unchanged. Regular mood-cycling was disturbed, together with the associated body-weight changes. There was a slight extracellular "metabolic" acidosis. Electrolyte concentrations fluctuate abnormally in these patients, and two muscle biopsy specimens had very low potassium contents.

Urinary dicarboxylic acids in patients receiving lithium or rubidium salts.

Lithium salts administered in therapeutic doses to four subjects who were kept on controlled diets increased up to fivefold the urinary output of some dicarboxylic acids. Some of the acids affected are intermediates in the tricarboxylic acid cycle, others are chemically similar but not directly related in metabolic terms. This is probably a direct effect on renal transport. Rubidium salts increased urinary 2-oxoglutarate output and blood 2-oxoglutarate levels, probably by some action on intermediary metabolism.

Diminished hypercapnic drive in endogenous or severe depression.

Resting breathing rate, resting end-tidal PCO2 and ventilatory response to CO2 were studied in patients with primary depression. Patients tended to breathe faster and showed decreased PECO2 levels when compared with control subjects. Carbon dioxide response was determined using a modification of the rebreathing technique of Read. Endogenous depressives, unlike reactive depressives, tended to give low CO2 responses and low CO2 thresholds. Carbon dioxide responses of patients on admission correlated highly with severity of depression. The modification of the standard rebreathing technique, and the relationship between CO2 response and physical and psychological variables are discussed.

Education for contraceptive use by women after childbirth.

BACKGROUND: n 1966, the Population Council (a non-profit, non-government organisation which aims to foster reproductive health around the world) sponsored demonstration projects (known as the 'International Postpartum Program') on postpartum family planning, focussing primarily on developing countries and including 25 hospitals in 14 countries (Zatuchni 1970). These projects were based on the assumptions that women are receptive to family planning education in the postpartum period, and that they will not return to health centres for contraception once they have been discharged from hospital. The demonstration projects were declared a success given their ability to reach large numbers of women, and they were expanded to include hospitals in 21 countries (Winikoff et al 1991). Randomised controlled trials were not used to assess the effectiveness of the program. The provision of education on contraceptive use to postpartum mothers has come to be considered a standard component of postnatal care, with up to 84% of women noting that a discussion on contraception took place with a midwife on the postnatal floor (Glasier et al 1996). Although education frequently is provided as an integral component of discharge planning, many women experience this as a perfunctory discussion included as part of a checklist of topics (Glasier et al 1996). Midwifery and obstetric texts routinely refer to the provision of such education as a responsibility in the provision of postpartum care; however, the effectiveness of this intervention is seldom questioned (Keith et al 1980; Semeraro 1996). Questions have been raised about the assumptions that are the basis for such programs, e.g. that postpartum women are motivated to use contraception and that they will not return to a health centre for family planning advice (Winikoff et al 1991). In addition surveys conducted postpartum indicate that women may wish to discuss contraception antenatally and post hospital discharge, preferably in the context of general education about maternal and child health (Ozvaris 1997). OBJECTIVES: Postpartum education on contraceptive use is a routine component of discharge planning in many different countries with a wide variety of health care systems. This education is based on assumptions concerning women's receptivity to contraceptive education during the postpartum period and their presumed lack of access to such education after that time. The objective of this review is to assess the effects of education about contraceptive use to postpartum mothers. SEARCH STRATEGY: We searched the Cochrane Controlled Trials Register, MEDLINE, EMBASE, CINAHL, Psychlit, Popline, citations indexes and reference lists of relevant articles. We contacted subject experts to locate additional research, in addition to the Group's Specialised Register of Controlled Trials. Date of the most recent search: March 2001. SELECTION CRITERIA: Trials using random or quasi-random methods of allocation which evaluated the effectiveness of postpartum education about contraceptive use. DATA COLLECTION AND ANALYSIS: Two independent reviewers abstracted data on trial characteristics and results. MAIN RESULTS: No new trials were identified since this review was updated in 1999. Three trials were identified with 5438 women. These trials were conducted in Lebanon, Peru and Nepal. None of the trials examined all major prespecified endpoints. Postpartum education about contraceptive use influenced short-term use assessed between 40 days and three months post-partum. Women in the intervention groups were less likely to be non-users than women in the comparison groups (Odds Ratio (OR) = 0.47, 95% Confidence Interval (CI) 0.39 to 0.58). This benefit was not apparent following analysis of data from better quality studies (OR = 0.67, 95% CI 0.41 to 1.13). An apparent benefit on contraceptive use at six months post-partum (OR = 0.52, 95% CI 0.37 to 0.74) was not apparent following sensitivity analyses (OR = 0.59, 95% CI 0.33 to 1.06). Data are inadequate to assess the impact on cessation of breast feeding and non-attendance at family planning clinics. Unplanned pregnancies, knowledge about contraception and satisfaction with care were not assessed in any trial. REVIEWER'S CONCLUSIONS: The effectiveness of postpartum education about contraceptive use has not yet been established in randomised controlled trials. Such education may be effective in increasing the short-term use of contraception. However, there are only limited data examining a more-important longer-term effect on the prevention of unplanned pregnancies. Research needs to be undertaken to assess the effectiveness of the minimalist education provided in more developed countries and the variety of programs provided in less developed regions. Such research should examine the content, timing, range and organisation of postpartum education on contraceptive use including lactational amenorrhea, as well as its impact on breast feeding rates.

Effects of rubidium chloride on the course of manic-depressive illness.

Clinical studies of the effects of rubidium ions on the course of manic-depressive illness are reported. It seems that rubidium tends to increase the length of manic phases and possibly reduces the extremes of mood. Rubidium did not seem to produce any severe side effects in the dose administered, but it has a long biological half-life and caution is still required. Some details of the CSF, RBC, saliva and plasma and urine kinetics are also reported.

Users' satisfaction with mental health services.

The opinion and level of satisfaction of the users of three different mental health services are presented as a way of evaluating the outcome of institutional and community approaches to psychiatric services. The information was collected in the cities of Concepcion (Chile), Sheffield (England) and Trieste (Italy) interviewing a sample of the users of the psychiatric services using a questionnaire specifically designed to suit the study's aims. The patients in Sheffield tended to support an eventual move towards a more community based service while the relatives appeared more interested in a general improvement of the traditional institutional facilities. In Trieste, patients as well as relatives are fully supportive of the community based services and reasonably aware of the difficulties. They want to improve things in the community. Finally, Chilean users show a considerable adherence to the more traditional and institutionalised ways of offering services and the levels of satisfaction were very high considering the conditions in which the help was delivered.

Attitudes of professional mental health workers to psychiatry.

An attempt is presented to measure and compare attitudes to and ideas about psychiatry and mental health services in Concepcion, Sheffield and Trieste. These cities have in some respects comparable populations but very different mental health services. Questionnaires in English, Italian and Spanish were used to assess the views of professional workers in the field. The information collected showed that the Italian professionals had the highest level of satisfaction with their work, showed most tolerance of deviant behaviour in the community, the least acceptance of diminished responsibility in law and a non-traditional view of psychiatry. Clearly Chilean professionals held a very traditional view and medicalised approach to mental illness but an encouraging theoretical approval towards eventual changes in the services, along with the lowest level of satisfaction with their work. Professionals from Sheffield held an intermediate position coming closer to the theoretical view of the Chileans but nearer to the Italian praxis and therapeutic approach.

Mentally abnormal homicide--a review of a special hospital male population.

The clinical, criminological and demographic characteristics of a Special Hospital population of male patients convicted of homicide are described. The results confirm much previous work on mentally abnormal homicide. Typically the patients come from a disadvantaged social background with poor employment records, a prior history of aggressive behaviour and a diagnosis of schizophrenia. Victims were usually known to the patient and often came from within his circle of family and friends. Only 25% of the patients were receiving treatment at the time of the offence. These findings are discussed in the light of the current literature.