Pleiotropic effects of melanin pigmentation: haemoparasite infection intensity but not telomere length is associated with plumage morph in black sparrowhawks

There is increasing recognition of the potential pleiotropic effects of melanin pigmentation, particularly on immunity, with reports of variation in haemoparasite infection intensity and immune responses between the morphs of colour-polymorphic bird species. In a population of the black sparrowhawk (Accipiter melanoleucus) in western South Africa, light morphs have a higher haemoparasite infection intensity, but no physiological effects of this are apparent. Here, we investigate the possible effects of haemoparasite infection on telomere length in this species and explore whether relative telomere length is associated with either plumage morph or sex. Using quantitative polymerase chain reaction analysis, we confirmed that dark morphs had a lower haemoparasite infection intensity than light morphs. However, we found no differences in telomere length associated with either the haemoparasite infection status or morph in adults, although males have longer telomeres than females. While differences in haemoparasite intensity between morphs are consistent with pleiotropic effects of melanin pigmentation in the black sparrowhawk, we found no evidence that telomere length was associated with haemoparasite infection. Further work is needed to investigate the implications of possible pleiotropic effects of plumage morph and their potential role in the maintenance of colour polymorphism in this species.

Using GPS tracking to monitor the breeding performance of a low-density raptor improves accuracy, and reduces long-term financial and carbon costs

Traditionally, demographic monitoring of birds has been undertaken by intensive monitoring of nesting sites. However, this is challenging for low-density species, whereby the effort and costs involved in locating and monitoring remote sites can be prohibitive or even bias research findings. We show that Global Positioning System (GPS) tracking can overcome these challenges for a low-density raptor. Field monitoring of martial eagles Polemaetus bellicosus from 2013 to 2021 showed consistently poor breeding performance, with a mean productivity of 0.22 (±0.04) fledged young/pair/year. Using GPS tracking data to infer breeding performance gave a significantly higher productivity of 0.46 (±0.10) fledged young/pair/year. Breeding rate and success were also underestimated by field monitoring. These differences were likely due to logistical constraints of field monitoring, particularly relating to finding alternative nests. Comparing costs between approaches, we estimated that GPS monitoring was financially cheaper than field monitoring per sample after 10 years. Carbon costs per sample were lower for GPS-based approaches than field monitoring from the second year, and over a 10-year period GPS monitoring produced considerable savings (200% less carbon). We recommend that despite high initial costs, for long-term demographic monitoring of low-density species, or where logistical constraints make traditional field monitoring inaccurate, remote monitoring options should be considered.

A utilization distribution for the global population of Cape Vultures (Gyps coprotheres) to guide wind energy development

The rapid development of wind energy in southern Africa represents an additional threat to the already fragile populations of African vultures. The distribution of the vulnerable Cape Vulture Gyps coprotheres overlaps considerably with wind energy development areas in South Africa, creating conflicts that can hinder both vulture conservation and sustainable energy development. To help address this conflict and aid in the safe placement of wind energy facilities, we map the utilization distribution (UD) of this species across its distributional range. Using tracking data from 68 Cape Vultures collected over the last 20 years, we develop a spatially explicit habitat use model to estimate the expected UDs around known colonies. Scaling the UDs by the number of vultures expected to use each of the colonies, we estimate the Cape Vulture population utilization distribution (PUD) and determine its exposure to wind farm impacts. To complement our results, we model the probability of a vulture flying within the rotor sweep area of a wind turbine throughout the species range and use this to identify areas that are particularly prone to collisions. Overall, our estimated PUD correlates well with reporting rates of the species from the Southern African Bird Atlas Project, currently used to assess potential overlap between Cape Vultures and wind energy developments, but it adds important benefits, such as providing a spatial gradient of activity estimates over the entire species range. We illustrate the application of our maps by analyzing the exposure of Cape Vultures in the Renewable Energy Development Zones (REDZs) in South Africa. This application is a scalable procedure that can be applied at different planning phases, from strategic, nationwide planning to project-level assessments.

A placebo and active comparator-controlled trial of rofecoxib for the treatment of rheumatoid arthritis

OBJECTIVE

To evaluate the efficacy and tolerability of rofecoxib 25 mg and 50 mg once daily versus placebo and naproxen 500 mg twice daily in patients with RA.

METHODS

Eligible patients were randomized (double-blind) to placebo (n = 289), rofecoxib 25 mg (n = 306), 50 mg (n = 286) once daily, or naproxen (n = 142) for 12 weeks. Efficacy assessments included the ACR core set, with prespecified primary endpoints: patient and investigator global assessments of disease activity, tender and swollen joint counts. Investigator-reported adverse experiences, routine laboratory and vital sign measurements were monitored.

RESULTS

Rofecoxib 25 mg, 50 mg, and naproxen provided similar treatment effects, significantly different from placebo, consistent with improvement, for all primary endpoints. Effects were evident at the earliest assessment (week 2) and sustained for 12 weeks. All treatments were generally well-tolerated.

CONCLUSIONS

Rofecoxib 25 mg once daily had similar efficacy to naproxen 500 mg twice daily (a standard dose). No additional benefit was seen with 50 mg rofecoxib.

Effects of the Magenstrasse and Mill operation for obesity on plasma plasminogen activator inhibitor type 1, tissue plasminogen activator, fibrinogen and insulin

Plasminogen activator inhibitor 1 (PAI-1), tissue plasminogen activator (t-PA), fibrinogen and insulin were measured in 43 patients 3 years after they had undergone the Magenstrasse and Mill (MM) procedure and in 43 morbidly obese (MO) patients. Mean plasma PAI-1 was 61 ng/ml in the MO group compared to 30 ng/ml in the MM group (p < 0.0001); mean plasma t-PA was 10 ng/ml in the MO group compared to 7 ng/ml in the MM group (p < 0.001). Mean fibrinogen was 3.6 g/l in the MO group compared to 3.2 g/l in the MM group (p < 0.05). Mean plasma insulin levels were 32 U/ml in the MO group compared to 15 U/ml in the MM group. These changes suggest that use of the MM procedure may reduce mortality and morbidity from coronary heart disease in these high-risk obese patients.

[Efficacy, tolerability and safety of cyclosporine for microemulsion in the treatment of active rheumatoid arthritis. Open study]

Cyclosporine for microemulsion has been widely used in the treatment of rheumatoid arthritis (RA) with remarkably good results over progression of joint damage, as reported by the GRISAR Study. A local group in Argentina, performed a prospective, open label study (Neo-Ra-02), consisting of 12 centres which recruited 50 RA patients, who were followed during 6 months in order to assess efficacy, tolerability and safety of cyclosporine microemulsion in the treatment of RA. Efficacy parameters were: morning stiffness, functional evaluation (HAQ, Lee and Ritchie index) and laboratory and radiological (Larsen score) assessments. Safety parameters were: blood pressure and renal, liver and hematological laboratory data. Patients criteria for participation were: presence of active RA (as defined by the ACR), Steinbrocker anatomic and functional grade I to III, disease evolution no longer than 5 years, no previous history of hypertension, renal or liver disease and absence of DMARDs use during the previous 2 months. There was a statistically significant decrease in morning stiffness and in pain evolution. Improvement became evident after 4 weeks of treatment. Reduction of Ritchie index was significant also at 4 weeks and the same observation was made with tenderness and swollen joint scores. Regarding evolution of CRP and RF, a statistically significant reduction was observed only in positive RF. Safety parameters showed no significant increase in serum creatinine or uric acid: 6/50 patients developed mild hypertension with only a significant increase in systolic blood pressure in comparison with baseline. Cyclosporine microemulsion demonstrated efficacy with minimal adverse events (12% mild hypertension) when appropriately monitored and administered in low doses (3 mg/kg/day).

Specific detection of epstein-barr virus in inflammatory pseudotumor of the spleen in a patient with a high serum level of soluble IL-2 receptor

A case of inflammatory pseudotumor of the spleen is described in a 63-year-old woman who presented with an intrasplenic tumor and an elevated serum level of soluble interleukin 2 receptor (sIL-2R). Microscopic examination after removal of the spleen revealed that the tumor was composed of mixed cellular infiltrates, mainly lymphocytes and plasma cells, and spindle-cell proliferation. Epstein-Barr virus (EBV) was specifically detected in the tumor by in situ hybridization for EBV RNA. The serum level of sIL-2R level was normalized after splenectomy. EBV infection may play a role in the development of splenic inflammatory pseudotumor and the elevation of sIL-2R level.

A novel mutation of desert hedgehog in a patient with 46,XY partial gonadal dysgenesis accompanied by minifascicular neuropathy

We describe a patient with 46,XY partial gonadal dysgenesis (PGD) who presented with polyneuropathy. Sural nerve pathology revealed peculiar findings characterized by extensive minifascicular formation within the endoneurium and with a decreased density of myelinated fibers. We found, in the patient, a homozygous missense mutation (ATG-->ACG) at the initiating codon in exon 1 of the desert hedgehog (DHH) gene, which predicts a failure of translation of the gene. The same heterozygous mutation was found in the patient's father. This is the first report of a human DHH gene mutation, and the findings demonstrate that mutation of the DHH gene may cause 46, XY PGD associated with minifascicular neuropathy.

Immunoblastic lymphadenopathy-like T cell lymphoma evolving into a massive plasma cell proliferation with biclonal paraproteinemia

We present a case of immunoblastic lymphadenopathy-like T cell lymphoma (IBL-T) who subsequently developed a massive proliferation of plasma cells. At diagnosis of IBL-T, the patient had polyclonal hypergammaglobulinemia and subsequently, while on chemotherapy, developed paraproteinemia with biclonal peaks and the IBL-T lesion was replaced with a massive proliferation of CD38-positive plasma cells. The evolution was not likely to be attributed to a new neoplastic proliferation of B cells. It appeared that two B cell clones possibly had a growth advantage among the polyclonal B cells due to a depletion of suppressor T cells or to a disturbance in the immune system.

Monitoring the effects of heparin: evaluation of a new portable device

The aim of this study was to measure the effects of heparin therapy in patients undergoing vascular surgery, and to monitor the effectiveness of continuous intravenous heparin therapy in ward-based patients. In addition, we compared results from a new portable device with those from the standard laboratory assay. A prospective comparison of the two methods in patients undergoing peripheral vascular surgery, and in ward-based patients who were receiving intravenous heparin infusions was undertaken. Fifty patients who were undergoing vascular surgery and receiving a bolus dose of intravenous heparin, and 22 patients receiving a continuous heparin infusion, were recruited. Blood samples were taken 10 and 40 min following bolus heparin administration or after > 12 h of a continuous heparin infusion. Plasma activated partial thromboplastin times (APTTp) measured by the haematology laboratory were compared with whole blood (APTT(B)) ascertained with the CoaguChek Plus Device (Boehringer Mannheim UK Diagnostics and Biochemicals Limited) at each time point. The results from the two methods were compared using the method of Bland and Altman (Lancet, 1986, 307-310). We found a good level of agreement between the two methods (at induction, mean bias was -0.050, limits of agreement -0.46 - 0.36; heparin infusions, mean bias was -0.283, limits of agreement -1.64 - 1.07). In addition we discovered that many of our patients appeared to be excessively anticoagulated during surgery (10 min following heparin bolus 47/50 patients had an APTT(B) > 150 s, 45/50 had an APTTp > 250 s; at 40 min 45/50 had an APTT(B) > 150 s, 39/50 had an APTTp > 250 s). In conclusion, whole blood APTT measurement allows rapid and accurate assessment of the effects of heparin therapy when compared with laboratory APTT measurement and may prevent both excessive and suboptimal anticoagulation.

A case of malignant Triton tumor of the lung

The present paper reports a 28-year-old male with an asymptomaticmalignant Triton tumor of the lung. Chest radiographs revealed a mass in the left hilum. The left lower lobe including the tumor and the mediastinal lymph node was resected. There was no metastasis or tumor recurrence during the one-year period following the surgical procedure. To our knowledge, this is the first case report of a primary pulmonary malignant Triton tumor.

Localization of the human IL-2-inducible T-cell kinase gene (ITK) to chromosome band 5q34 and the mouse gene (Itk) to chromosome 15 by fluorescence in situ hybridization

ITK, predominantly expressed on T cells and myeloid cells, is a member of the Tec nonreceptor tyrosine kinase family. Both human ITK and mouse Itk genomic clones were isolated to assign the chromosome location. The human ITK gene was mapped to chromosome band 5q34 and the mouse gene to chromosome 15 by fluorescence in situ hybridization.

Capacitative Ca2+ entry exclusively inhibits cAMP synthesis in C6-2B glioma cells. Evidence that physiologically evoked Ca2+ entry regulates Ca(2+)-inhibitable adenylyl cyclase in non-excitable cells

Elevation of cytosolic free Ca2+ inhibits the type VI adenylyl cyclase that predominates in C6-2B cells. However, it is not known whether there is any selective requirement for Ca2+ entry or release for inhibition of cAMP accumulation to occur. In the present study, the effectiveness of intracellular Ca2+ release evoked by three independent methods (thapsigargin, ionomycin, and UTP) was compared with the capacitative Ca2+ entry that was triggered by these treatments. In each situation, only Ca2+ entry could inhibit cAMP accumulation (La3+ ions blocked the effect); Ca2+ release, which was substantial in some cases, was without effect. A moderate inhibition, as was elicited by a modest degree of Ca2+ entry, could be rendered substantial in the absence of phosphodiesterase inhibitors. Such conditions more closely mimic the physiological situation of normal cells. These results are particularly significant, in demonstrating not only that Ca2+ entry mediates the inhibitory effects of Ca2+ on cAMP accumulation, but also that diffuse elevations in [Ca2+]i are ineffective in modulating cAMP synthesis. This property suggests that, as with certain Ca(2+)-sensitive ion channels, Ca(2+)-sensitive adenylyl cyclases may be functionally colocalized with Ca2+ entry channels.

Structural similarity of the HLA-DQ region in DQ3 and DQ4 haplotypes and structural diversity of the HLA-DQ region in HLA-DR7 haplotypes

Genomic DNA obtained from a B lymphoblastoid cell line was digested with appropriate restriction endonuclease and hybridized with several probes specific for genes encoding HLA-DQ. Southern hybridization with a DQA1 3'untranslated (UT) region probe showed DQ2-type hybridization pattern in DR7DQ3 haplotype. On the contrary, DQB1 3'UT probe showed DQ3-type pattern in the same haplotype. Gene cloning and DNA sequencing analysis revealed a repetitive sequence, (TG)19, between DQA1 and DQB1 gene in the DR7DQ3 haplotype. These results suggest that a recombination event has occurred near this potential Z-DNA structure in the haplotype, DR7DQ3. The 3'UT region probes of DQA1 and DQB1 genes failed to detect restriction fragment length polymorphism (RFLP) differences between DR4DQ3 and DR4DQ4 haplotypes in this experiment, suggesting that the gene structure between DQA1 and DQB1 is conserved in these haplotypes.

Regulation of lipopolysaccharide- and IL-4-induced immunoglobulin heavy chain gene activation: differential roles for CD45 and Lyb-2

We have demonstrated that CD45, a receptor-type protein tyrosine phosphatase, selectively regulates IgG production at the generative phase of precursors of IgG producers whereas Lyb-2 regulates IgG1 production induced by IL-4 in lipopolysaccharide (LPS)-activated B cells by acting on the generation of IgG1 precursor cells. These results point to an interesting possibility that both CD45 and Lyb-2 mediate a critical regulatory step(s) in IgG class switching. The present study was conducted to examine this possibility by elucidating the molecular mechanisms whereby CD45 and Lyb-2 control IgG synthesis in B cells activated by LPS and IL-4. Northern blot analysis showed that steady-state levels of C gamma 3, C gamma 2b and C gamma 1, but not Cmu, mRNA in LPS-activated B cells were reduced approximately 3- to 5-fold by CD45 mAb, and that the C gamma 1 mRNA level in B cells activated by LPS and IL-4 was significantly decreased by Lyb-2 mAb and CD45 mAb. Further, CD45 mAb inhibited expression of germline gamma 2b and gamma 3 transcripts induced by LPS and germline gamma 1 transcript expression induced by IL-4 plus LPS, but caused no inhibition in IL-4-induced germline gamma 1 transcript expression. In contrast, Lyb-2 mAb did not exert any inhibitory effect on the generation of germline gamma 1 transcripts induced by IL-4 and LPS or by IL-4 alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression and structure of serum gp70 as an acute phase protein in NZB mice

A cDNA corresponding to a serum gp70 synthesized as an acute phase protein in mouse hepatocytes was cloned and analyzed. This cloned cDNA had the characteristics of an endogenous xenotropic murine leukemia virus. Synthesized oligo-DNA specific for this cDNA reacted strongly with liver RNA derived from NZB mice injected with LPS as a trigger of an acute phase inflammatory response. There was also low level of gp70 in the kidney in response to LPS injection. The LTR structure of the cDNA showed that this clone is the immediate precursor of an infectious xenotropic virus in the proposed evolutionary scheme of murine leukemia virus.

Autoreactivity in women with endometriosis

Serum samples from 71 patients with laparoscopically staged endometriosis and from 109 age-matched non-pregnant control women were tested for antibodies to nuclear, phospholipid, smooth muscle and sperm antigens. Immunoglobulin G, M and A and complement components C3 and C4 were measured. Prevalence of the following autoantibodies was statistically significantly greater in women with endometriosis than in the control group: antinuclear antibodies, antibodies to ribonucleoproteins, smooth muscle antibodies, lupus anticoagulant and anticardiolipin antibody. Forty-one women with endometriosis (58%) had some type of autoantibody compared with 13 controls (12%). More women in the endometriosis group had IgG and IgM levels above the normal range. This was statistically significant for IgG in women with grade 3 and for IgM in those with grade 4 endometriosis, IgG levels were significantly higher in antibody-positive women with endometriosis than in the control group. Immunoglobulin and complement component levels tended to have a positive correlation with stage of disease.

Function of the hydrophobic transmembrane portion of Thy-1 antigen

Thy-1 antigen is anchored in the cell membrane by glycophosphatidyl inositol linkages instead of hydrophobic protein domains. The hydrophobic portion of Thy-1 antigen is cleaved by putative "transamidase." Mutated genes were constructed by using site-directed mutagenesis. One mutant gene codes Thy-1 antigen lacking carboxy terminal amino acids from 112Cys to 143Leu including cell membrane binding amino acid 112Cys. The other mutant gene codes Thy-1 antigen lacking from 124Trp to 143Leu that includes leucine core portion. DNA transfection analysis and Northern blot analysis revealed that hydrophobic portion of Thy-1 antigen is essential to express Thy-1 molecule onto the cell surface.

Effect of warfarin on plasma concentrations of vitamin K dependent coagulation factors in patients with stable control and monitored compliance

There is a discrepancy in the results of reported studies of levels of vitamin K dependent coagulation factors in patients on warfarin therapy. This may have arisen partly because of the problem of assuring compliance with therapy in outpatients. The plasma concentrations of the vitamin K dependent clotting factors II, VII, IX and X were studied in 23 outpatients whose adherence to prescribed warfarin therapy was determined using a pharmacological indicator of compliance. In these patients, who were shown to have consistently good compliance and stable anticoagulant control over a period of 3-6 months, the activities in plasma of the four coagulation factors were not equally suppressed. Factor IX levels were significantly greater than those of factor VII (P less than 0.0001) which in turn were significantly greater than the levels of factor II (P less than 0.0001) or factor X (P less than 0.0001). There was no significant difference between the levels of factors II and X which were depressed to a similar extent. The proportion of variability of the International Normalized Ratio (INR) explained by linear regression was 51-77% and a model was derived to predict the INR from the mean of the levels of the four clotting factors. The concentrations of the coagulation factors II, VII, IX and X are likely to be highly dependent on the degree of compliance with warfarin therapy which should be taken into account when investigating the behaviour of these factors.

Suppression of human synovial cell proliferation by dihomo-gamma-linolenic acid

Prostaglandin E1 (PGE1) and oils enriched in its precursor fatty acids suppress inflammation and joint tissue injury in several animal models. Since synovial cell proliferation is a hallmark of rheumatoid arthritis, we studied the effect of dihomo-gamma-linolenic acid (DGLA), an immediate precursor of PGE1, on the growth of human adherent synovial cells (ASC) in tissue culture. When stimulated by appropriate concentrations of recombinant interleukin-1 beta (rIL-1 beta), ASC proliferate and produce PGE. DGLA-enriched medium suppressed both baseline and rIL-1 beta-stimulated ASC growth fivefold, compared with medium supplemented with arachidonic acid. Indomethacin reduced the effect of the DGLA. Synovial cells incorporated the DGLA, and rIL-1 beta-stimulated cells that were incubated with DGLA exhibited a 14-fold increase in PGE1 (to 25.2 +/- 6.0 ng/ml, mean +/- SD) and a 70% decrease in PGE2 (to 25.2 +/- 4.2 ng/ml) compared with cells in control medium. At equivalent concentrations (5 x 10(-7) M), PGE1 increased the level of cellular cAMP to a greater extent than did PGE2 (16.8 +/- 2.0 pmoles versus 4.3 +/- 1.9 pmoles, mean +/- SEM). Exogenous PGE1 was also a more effective inhibitor of cell growth. Similarly, cAMP concentrations in cells exposed to DGLA for 6 hours were greater than concentrations in arachidonic acid-enriched cultures (17.8 +/- 3.3 pmoles versus 2.1 +/- 2.0 pmoles). These observations suggest that DGLA can restrain ASC growth, an effect which may be due to its capacity to increase PGE1 production and subsequent cellular cAMP concentration.

Suppression of acute and chronic inflammation by dietary gamma linolenic acid

We examined the effect of diets enriched in gamma linolenic acid (GLA) on acute inflammation induced by monosodium urate crystals, and on subacute and chronic inflammation induced by complete Freund's adjuvant in the rat subcutaneous air pouch and in rats with adjuvant induced arthritis. Diets were enriched (15% fat) with borage seed oil (23% GLA) or safflower oil (less than 1% GLA). Diets enriched with GLA suppressed inflammation markedly in all models, whereas the safflower oil diet did not influence the inflammatory response. The degree of inflammation was quantified by measuring pouch exudate cell concentration, lysosomal enzyme activity, volume, protein concentration and prostaglandin E2 and leukotriene B4 concentrations. In the chronic air pouch model, the pouch lining was thickened, invaded by mononuclear cells and exhibited proliferation of lining cells 14 days after adjuvant injection. The lesion was far less severe and usual pouch lining architecture was maintained in animals given dietary GLA. Livers of rats fed borage seed oil were enriched in GLA and dihomo gamma linolenic acid (DGLA), and the DGLA/arachidonate ratio was increased 5-fold compared with animals fed safflower oil. Enrichment of diet with plant seed oils rich in GLA may provide a way to alter generation of prostaglandins and leukotrienes and to influence acute and chronic inflammatory responses.

Inflammation after blood injection into a synovial-like space is a result of the cellular component rather than the plasma

The rat subcutaneous air pouch, a model for a synovial-like space, has been used to study the effect of blood as an inducer of inflammation. Six-day-old pouches were injected with autologous whole blood, with plasma or with blood cell pellets. We found significantly more inflammation and proliferation of pouch lining in pouches injected with whole blood or with the blood cell pellets than with the plasma. After the injection of blood or the cell component, large numbers of hemoglobin crystals and lipid droplets were found in the pouch fluid and were associated with erosions of the pouch membrane.

The use of warfarin in pregnancy complicated by circulating lupus anticoagulant; a technique for monitoring

A case is described in which a pregnancy, preceded by two mid-trimester fetal losses, was complicated by deep-vein thrombosis due to the presence of circulating lupus anticoagulant. Warfarin was used as anticoagulant therapy concurrently with high-dose prednisolone. It is suggested that warfarin may have advantages over heparin in managing pregnancies in women with circulating lupus anticoagulant. A technique is described which allowed the monitoring of levels of lupus anticoagulant in the circulation while warfarin is being administered.h3.

Partial N-terminal sequence analysis of DRw53 antigens: the beta-chains of DRw53 antigens are structurally distinct from beta-chains of DR and DQ antigens

DRw53 antigens were isolated from DR7-homozygous and DRw9-homozygous cell lines with an alloantiserum, Hon, containing an anti-DRw53 alloantibody. Partial N-terminal sequence analysis of the isolated DRw53 antigens revealed that DRw53 alpha-chains have sequences indistinguishable from those of DR alpha-chains. In contrast, DRw53 beta-chains have sequences distinct from those of the DR beta-chains and DQ beta-chains isolated from the same cell lines. The DRw53 beta-chains are also distinct from DP beta-chains. These results suggest that the DRw53 beta-chains chains are products of a gene that has not yet been well characterized in the HLA-D region.

Partial N-terminal sequence analysis of DRw53 antigens: the beta-chains of DRw53 antigens are structurally distinct from beta-chains of DR and DQ antigens

DRw53 antigens were isolated from DR7-homozygous and DRw9-homozygous cell lines with an alloantiserum, Hon, containing an anti-DRw53 alloantibody. Partial N-terminal sequence analysis of the isolated DRw53 antigens revealed that DRw53 alpha-chains have sequences indistinguishable from those of DR alpha-chains. In contrast, DRw53 beta-chains have sequences distinct from those of the DR beta-chains and DQ beta-chains isolated from the same cell lines. The DRw53 beta-chains are also distinct from DP beta-chains. These results suggest that the DRw53 beta-chains chains are products of a gene that has not yet been well characterized in the HLA-D region.

[Analysis of HLA-class II antigen mRNAs on T lymphoblasts]

The expression of human class II antigens on T lineage cells was analysed at the mRNA and the protein levels. Alpha- and beta-chains of class II antigens were identified on phytoheamagglutinin (PHA)-activated T lymphoblasts by two-dimensional polyacrylamide gel electrophoresis analysis. It was, however, not clear whether their spots represent HLA-DR, DQ or -DP antigen. Northern blot analysis using cDNA probes for alpha- and beta-chains of DR, DQ, and DP antigens revealed that mRNAs for all the class II antigen components were detected in PHA-activated T lymphoblasts. Among six T lymphoblastoid cell lines studied (Molt 4, RPMI 8402, CCRF-CEM, TALL 1, HSB 2 and MT-2), only MT-2, a human T cell leukemia virus-1 producing line, expressed class II antigen molecules and their mRNAs. The rest of the lines did not express class II antigens either at the protein level or at the mRNA level. However, Southern hybridization showed that these cell lines retained DQ beta-chain gene at the DNA level.

Prevention of intraventricular haemorrhage by fresh frozen plasma

Seventy three preterm infants weighing less than 1500 g or less than 32 weeks' gestation, or both, were allocated randomly to treatment (fresh frozen plasma 10 ml/kg on admission and at 24 hours of age) or control groups. Fifteen (41%) out of 37 control patients sustained intraventricular haemorrhage compared with five (14%) of 36 patients receiving treatment (X2 = 5.24, P = 0.022). No difference was found in coagulation factors measured at birth or at 48 hours of age in both groups. Fresh frozen plasma appears to have a beneficial effect in the prevention of intraventricular haemorrhage.

The myelodysplastic syndromes--a study of haemostatic function and platelet ultrastructure

The myelodysplastic syndromes (MDS) are characterised by dysplastic marrow and cytopenia. Clinically detectable bleeding is uncommon and usually attributed to thrombocytopenia. We have investigated some aspects of haemostatic function in 17 patients with MDS and compared the results with findings from 17 control patients matched for age and sex. No specific disorder of blood coagulation or fibrinolysis was identified. The main abnormalities observed in the patients were: prolongation of the bleeding time which was greater than could be explained on the basis of thrombocytopenia in 13 patients; absent, or severely impaired platelet aggregation in response to collagen in 7 patients; impaired platelet production of malondialydehyde when stimulated with collagen and abnormal release of 14C-5 hydroxytryptamine in 5 patients; and abnormalities of ultrastructure in all 5 patients whose platelets were viewed by electron microscopy.

The effect of blinding and pinealectomy in unilaterally ovariectomized rats

Bilateral optic enucleation was observed to block partially the hypertrophy of the remaining ovary in unilaterally ovariectomized rats of a Charles River, CD strain. The inhibitory effects of blinding on compensatory ovarian hypertrophy (COH) were reversed when pinealectomy was performed at the same time as bilateral optic enucleation, three weeks prior to unilateral ovariectomy. Sham pinealectomy was without effect. When only pinealectomy was performed, a slight increase in COH was observed.

Serum follicle stimulating hormone (FSH) levels were estimated by a modification of the Steelman-Pohley bioassay in control, blinded, blindedpinealectomized and pinealectomized rats following unilateral ovariectomy. The increase in serum FSH at four days was blocked by blinding, an effect which was abolished by coupling pinealectomy with optic enucleation. Pinealectomy alone was followed by an increase in serum FSH slightly above control values.

These experiments demonstrate the blockage of COH by blinding and the mediation of this effect of blinding by the pineal gland. They further suggest that the increased secretion of FSH into the blood following unilateral ovariectomy is reduced under pineal influence.