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Blood platelet counts and mean platelet volumes were determined at weekly intervals for eight weeks in 13 pre-menopausal and 11 post-menopausal females. Samples were analysed exactly two hours after blood collection on a Coulter S plus VTM particle counter. Pre-menopausal platelet counts were slightly higher than post-menopausal counts at each week, but the count was not affected by the menstrual cycle, intra-individual variation showing mean coefficients of variation (CV) of 7.4% and 5.2% respectively. The mean platelet volume was similar in pre- and post-menopausal groups at each week and showed little variability over time (mean CV 2.7% and 3.3%, respectively). Platelet parameters show little variability over time in either group and with no cyclical effects of menstruation apparent.

MSA2 is a strain variable blood-stage merozoite surface antigen of Plasmodium falciparum. We have derived the MSA2 nucleotide sequence for four cloned parasite isolates. Comparison with three other published sequences suggests that variation may be limited, and that the architecture of the gene can be conveniently described by segregation into four distinct regions. The N and C terminal regions (Regions 1 and 4) are highly conserved in all seven genes. Six of these seven MSA2 genes can be grouped in a single family, within which variation is largely limited to a region characterized by the presence of tandem repeats (Region 2). We have observed two new forms of repeat in a Gly, Ser, Ala-rich block, and noted the absence of repeat in this block of the CAMP strain. The region downstream of the repeat region (Region 3) is highly conserved within this family. Immunochemical analysis reveals that MSA2 is one of the antigens recognized by immune antibodies eluted from intact merozoites. Regions 2 and 3, expressed as recombinant proteins, are recognized by these antibodies, suggesting that these regions are exposed at the surface of the intact merozoite.

Surgical procedures involving the maxilla require details regarding the topography of the nasal floor and that of the maxillary sinus. Panoramic zonography can provide this information with a minimum of radiation exposure and may be used in certain instances when other imaging modalities cannot. Spatially dependent variations in vertical magnification inherent to panoramic zonography using the midface program were determined. Radiographic lengths of marker wires attached at seven locations along the maxillary arch of dry skulls were measured. Radiographs were obtained at 0, -10 and -20 mm shifts. Analysis of variance and ranking did not reveal any significant differences in magnification between skulls. However, a dichotomy between the anterior and posterior portions of the maxillary arch in terms of vertical magnification was found at all three shift positions. In addition, at all marker locations, the magnification diminished as a function of decreasing shift position. These variations are due to the fact that teeth within the arch are not all located at the central plane of the focal trough generated by the unit. The results provide the clinician with vertical magnification factors from which actual measurements can be derived from zonographs.

The Plasmodium falciparum gene encoding erythrocyte binding antigen-175 (EBA-175), a putative receptor for red cell invasion (Camus, D., and T. J. Hadley. 1985. Science (Wash. DC). 230:553-556.), has been isolated and characterized. DNA sequencing demonstrated a single open reading frame encoding a translation product of 1,435 amino acid residues. Peptides corresponding to regions on the deduced amino acid sequence predicted to be B cell epitopes were assessed for immunogenicity. Immunization of mice and rabbits with EBA-peptide 4, a synthetic peptide encompassing amino acid residues 1,062-1,103, produced antibodies that recognized P. falciparum merozoites in an indirect fluorescent antibody assay. When compared to sera from rabbits immunized with the same adjuvant and carrier protein, sera from rabbits immunized with EBA-peptide 4 inhibited merozoite invasion of erythrocytes in vitro by 80% at a 1:5 dilution. Furthermore, these sera inhibited the binding of purified, authentic EBA-175 to erythrocytes, suggesting that their activity in inhibiting merozoite invasion of erythrocytes is mediated by blocking the binding of EBA-175 to erythrocytes. Since the nucleotide sequence of EBA-peptide 4 is conserved among seven strains of P. falciparum from throughout the world (Sim, B. K. L. 1990. Mol. Biochem. Parasitol. 41:293-296.), these data identify a region of the protein that should be a focus of vaccine development efforts.

We present an autopsy case of concomitant pulmonary aspergillosis and nocardiosis undiagnosed during life in a long-term surviving renal transplant recipient. The patient had fever and a newly developed cavitary lesion on a chest x-ray. The working diagnosis was pulmonary tuberculosis with possible colonization by Aspergillus species. Cultures of bronchial washings became positive for Aspergillus fumigatus 1 day after death. The study of tissue from the lung cavity at autopsy revealed Aspergillus fumigatus (confirmed by postmortem culture) and the filaments of Nocardia species. Increased numbers of surviving immunosuppressed patients will require aggressive, comprehensive diagnostic techniques for the detection of polymicrobial infections.

Lasting immunity against Rickettsia tsutsugamushi, the causative agent of scrub typhus fever, has been demonstrated to be strain specific. Two protein antigens of 110 and 56 kilodaltons (kDa) have been shown to exhibit strain-specific epitopes. The 56-kDa scrub typhus antigen (Sta56) is an abundant outer membrane protein of R. tsutsugamushi and is an antigen often recognized by humans infected with this obligate intracellular bacterium. In this study the complete gene encoding Sta56 (strain Karp) was cloned into pBR322 on a 2.3-kilobase genomic HindIII DNA fragment and the complete 56-kDa polypeptide was expressed in Escherichia coli. DNA sequence analysis of the 2.3-kilobase HindIII fragment revealed an open reading frame large enough to encode a 56-kDa polypeptide. A putative signal sequence was identified at the deduced amino terminus of the Sta56 polypeptide, and pulse-chase analysis of maxicells labeled with [35S]methionine demonstrated that a higher-molecular-weight precursor matures into the 56-kDa polypeptide. Epitope scanning analysis with synthetic peptides derived from the deduced amino acid sequence identified an octapeptide (located from amino acid residues 117 to 124) that was reactive with a Karp strain-specific monoclonal antibody (K13F88A). Other epitopes recognized by different monoclonal antibodies, including another Karp strain-specific monoclone (K1E106), were localized to different regions of the protein based on their reactivities with lambda gt11 recombinants expressing various portions of the sta56 gene.

Abnormalities that have been reported for platelet indices and function, coagulation factors and tests, and the fibrinolytic system in hypothyroidism are reviewed. These abnormalities, although usually of limited importance clinically, may occasionally lead to major bleeding episodes and to diagnostic confusion.

Forty-six (92%) outborn and four (8%) inborn term or near-term neonates were admitted for extracorporeal membrane oxygenation (ECMO) treatment to a neonatal intensive care unit between July 1, 1985, and November 1, 1987. All infants had PAO2-PaO2 greater than or equal to 600 mm Hg in spite of aggressive conventional ventilatory and pharmacologic therapy. All patients were offered rescue treatment with high-frequency oscillatory ventilation (HFOV), and only if there was no improvement in PAO2-PaO2 with HFOV were infants treated using ECMO. Four patients died before receiving an adequate trial of HFOV and before emergency ECMO support could be initiated; 21 patients, all of whom survived to hospital discharge, responded to HFOV; 25 patients ultimately required ECMO therapy for cardiopulmonary support, with 22 (88%) surviving to discharge. Neonates responding to HFOV were of slightly younger gestational age (38 +/- 2 weeks vs 40 +/- 2 weeks, mean +/- SD; P less than .001) and more frequently had clinical evidence of pneumonia (11 of 21 vs 2 of 25; P less than .002). There was no statistically significant difference in outcome with respect to the number of ventilator days, hospital days, or survival between patients responding to HFOV and patients who required ECMO. Morbidity was increased in ECMO patients, with bleeding abnormalities, seizures, and renal failure occurring more frequently than in HFOV-treated infants. Overall, 92% (46 of 50) of the patients were treated with a staged protocol using HFOV before ECMO. A total of 46% (21 of 46) responded to HFOV treatment alone and did not require ECMO therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

A series of experiments was conducted to examine the effects of the N-oxidized metabolite of procainamide, procainamide hydroxylamine (PAHA), on reactive oxygen species (ROS) production by macrophages in vitro, as well as on the release of the cytokine interleukin-1 (IL-1). Results with PAHA were compared with those from the parent compound, procainamide, and in some cases with other procainamide metabolites such as N-acetylprocainamide or nitrosoprocainamide. The effects of PAHA on ROS production by mouse and rat macrophages were complex, resulting in both stimulatory and inhibitory activity depending upon the PAHA concentration and whether macrophages were resting or elicited. The primary effect of PAHA appeared to be a stimulation of ROS production. Monocytes pretreated with PAHA (20 microM) depressed the responsiveness of lymphocytes in co-culture to a T-cell mitogen (conconavalin A) but not a B-cell mitogen (lipopolysaccharide). This effect was inhibited when monocyte pretreatment with PAHA was accompanied by the antioxidants, catalase or superoxide dismutase. IL-1 production by rat adherent splenocytes was unaffected by PAHA in concentrations that were not cytotoxic. These observations suggest that the oxidative metabolism of procainamide to PAHA may result in enhanced production of ROS by macrophages contributing its toxicity to lymphocytes.

In 83 healthy normotensive males aged 20-55 years the platelet count is positively correlated with the red cell count (r = 0.371; P = 0.0006), the white cell count (r = 0.358; P = 0.0009), and with weight (r = 0.252; P = 0.0269). The red cell count is also positively related with the white cell count (r = 0.242; P = 0.0278) and with weight (r = 0.326; P = 0.0039); while the white cell count is slightly correlated with weight (r = 0.210; P = 0.067). These findings provide further indirect evidential support for a haemopoetic growth factor acting on a single pluripotent stem cell.

Serum and red blood cell folate levels and serum B12 concentration were determined by radioassay in 20 hyperthyroid patients and compared with values obtained when the same patients had been euthyroid for at least 4 months. In hyperthyroidism, the levels of serum and red blood cell folate were significantly (P less than .01) higher than when euthyroidism was achieved. There was no significant change in serum B12 concentration. Declines in serum and red blood cell folate levels between hyperthyroidism and euthyroidism occurred in 15 and 16 of the 20 patients, respectively. Although the explanation for the relative elevations of serum and red blood cell folate levels in hyperthyroid patients is unclear at present, our findings do not support the view that hyperthyroidism in man is associated with depletion of folate stores or subclinical deficiency of the vitamin.

Eighty-eight teeth were used to determine the sealing quality of four root canal sealer cements--Kerr, Diaket, AH-26, and ProcoSol--via the vertical condensation of warm gutta-percha technique. In addition, limited studies were carried out to determine the sealing quality of injected Hydron and thermoplasticized gutta-percha. A comparison was also made between the lateral condensation of gutta-percha and vertical condensation of warm gutta-percha when Kerr sealer was used. Teeth filled with vertical condensation of warm gutta-percha and AH-26 sealer cement showed lower leakage in one experiment but higher leakage in another. Hydron showed the highest leakage of any material. Teeth filled via vertical condensation of warm gutta-percha and Diaket showed less leakage than the other groups. A statistically significant difference was also found between lateral condensation of gutta-percha and vertical condensation of warm gutta-percha using Kerr sealer cement.

Plano-parallel specimens of human dentin cut from vital and endodontically treated teeth were tested by the punch shear test. Shear strength values were found to positively correlate with approximate toughness values. Statistically significant differences were found between shear strength and toughness values for vital and endodontically treated teeth, the latter showing lower values. The clinical impression that endodontically treated teeth are weaker and more brittle than vital teeth has therefore been quantitated. Anatomically different teeth or the methods used to store and cut teeth could not be consistently correlated with punch shear and toughness values. When dentin slices were constrained during punching so that bending was prevented, the precision of the results was improved and higher values were recorded.

The purpose of this study was to determine the use of continuous intraperitoneal insulin infusion over an extended period (in maintaining metabolic control) and to evaluate the benefits of this treatment in reversing the kidney pathology of a chronic diabetic dog with membranous glomerulopathy. Hyperglycemia was eliminated, but reevaluations of the insulin infusion pattern were necessary. An initial kidney biopsy revealed fusion of the foot processes, thickening of the basement membrane, and subendothelial deposition. After 5 months of infusion, there was less fusion of the foot processes and a decrease in the subendothelial deposition. Urinary protein loss decreased from 17.3 g/day to 625 mg/day after 2 months of infusion. The dog gained weight, muscle wasting was reversed, and his stamina returned while on continuous insulin infusion. The reduction of a life-threatening urinary protein loss to a tolerable level and the improvement in the microscopic kidney lesions observed indicate that this treatment with insulin infusion may be beneficial in the management of long-term diabetic dogs, affected with advanced kidney lesions secondary to diabetes.

Etching techniques to prepare ultra-thin sections for immunoelectron microscopy have incorporated a variety of reagents to expose antigenic sites. In this paper involving 2 techniques for surface etching prior to immunoelectron microscopy, radio frequency glow discharge ( RFGD ) and solid-phase lactoperoxidase-glucose oxidase beads ( Enzymobeads ) are compared to conventional peroxide etching techniques. Measuring such parameters as intensity of granule disposition and titers of antibody resulting in detectable staining. RFGD and Enzymobeads were both superior to the conventional peroxide methodology. Non-specific absorption by ferritin under the conditions utilized was not a problem with Enzymobeads or RFGD method. In addition, RFGD may be useful in situations where peroxide susceptible antigens are under study.

A case of transfusion-related AIDS is described which is believed to be the first published case to occur in New Zealand in a nonhaemophiliac patient. The human immunodeficiency virus (HIV) positive donor was shown to be the source of infection in five further HIV positive recipients.

Spleen cells from hamsters immunized with recombinant mouse interferon-gamma (IFN-gamma) were fused with mouse myeloma cells, resulting in the production of four anti-IFN-gamma monoclonal antibodies. Binding of 125I-IFN-gamma by these protein A-bound antibodies was specifically blocked by cold IFN-gamma. Binding by three of these antibodies was also blocked by a synthetic peptide corresponding to the N-terminal 1-39 amino acids of IFN-gamma, whereas a corresponding C-terminal (95-133) peptide had no effect on binding. The N-terminal specificity of these three antibodies was confirmed by their specific binding of 125I-N-terminal (1-39) peptide. One of the N-terminal specific monoclonal antibodies inhibited both antiviral and macrophage priming (for tumor cell killing) activities of IFN-gamma, whereas the other two had no effect on either biologic function. The selectivity of the inhibition of IFN-gamma function was not due to a differential ability of the N-terminal specific antibodies to bind IFN-gamma. Blocking experiments with cold IFN-gamma and N-terminal peptide suggest that the epitope specificities of the monoclonal antibodies could be determined by the conformational or topographic structure of IFN-gamma. An exact determination of the epitope specificity of the monoclonal antibody that inhibited IFN-gamma function could provide insight into the structural basis for the role of the N-terminal domain in the biologic function of IFN-gamma. Polyclonal antibodies to either the N-terminal or the C-terminal peptides also inhibited both the antiviral and the macrophage-priming activities of IFN-gamma. All of the antibodies that inhibited IFN-gamma function also blocked binding of IFN-gamma to membrane receptor on cells, whereas antibodies that did not block function also did not inhibit binding. The data suggest that both the N-terminal and the C-terminal domains of IFN-gamma play an important role in its antiviral and macrophage-priming functions, possibly in a cooperative manner.

Conventional finishing and polishing techniques used to prepare Vitallium subperiosteal dental implant castings were found to produce low energy surfaces as measured by critical surface tension. Standard metallographic preparation gave slightly higher values. Glow discharge cleaning of both types of polished surface gave much higher critical surface tension values. This suggests the presence of an organic film after surface polishing of the implant which may later affect tissue reaction, in particular attachment, as has been noticed in related animal studies.

We have described a patient who had a clinical picture of CREST syndrome and pulmonary interstitial fibrosis, and in whom adenocarcinoma of the lung developed over a four-year period. Despite absence in the literature of the association of lung carcinoma in patients with CREST syndrome, our case is an example of pulmonary fibrosis complicated by lung cancer without any evidence of other risk factors. We believe this to be the first report of such an association. Clinicians, therefore, must be aware that pulmonary interstitial fibrosis in patients with the CREST syndrome may represent a risk for lung cancer.

In order to study the influence of residual stresses on dimensional accuracy and mechanical properties of denture bases, an experimental model was devised for measurement of residual stresses in acrylic denture base polymers. Rectangular bar coupons were cut from resin plates heat processed by conventional dental methods. They included samples which had been slow and fast cooled after polymerization and had been stored in dry and wet environments. Uniaxial residual stress distributions for each coupon were disclosed by removing layers of known thicknesses and measuring the ensuing deflection of the specimens. Coupons of a commercial acrylic resin were annealed and used as controls. ANOVA and Scheffe's test were used to compare experimental conditions at the 95% confidence level. Dry specimens exhibited residual surface compressive stresses from 0.43-0.83 MPa (62-120 psi). Water-stored specimens showed higher stress levels, 2.86-3.24 MPa (414-470 psi). Slow cooled pigmented acrylic coupons which were dry showed higher residual stresses compared with other dry but nonpigmented specimens. No significant differences were found between pigmented or clear coupons which contained moisture.

Pulmonary complications are common in patients with acute leukaemia. Infection is the usual cause of these. A case of acute leukaemia is described in which diffuse interstitial pneumonitis developed during remission induction therapy. This occurred during a very rapid fall in the leukaemic blast population following the start of chemotherapy. Open lung biopsy showed necrotic leukaemic cells filling the lung interstitium. The patient made an uneventful recovery from this complication.

This investigation developed experimental evidence for the influence of different surface energy states on tissue incorporation of biomedical materials. Implants of two smooth metals, each with three different surface energy states, were placed in the subdermal fascial plane of the backs of New Zealand White rabbits and were allowed healing times of 10 and 20 days. The implant surfaces were thoroughly characterized by physical-chemical criteria prior to surgical placement and again following removal from the tissue capsules generated by the host animals. Quantitative histopathologic analysis, using standard morphometric criteria, of the adjacent tissues revealed up to a threefold increase of fibroblastic-fibrocytic cells against the initially scrupulously cleaned, high-surface-energy materials. The cells were flattened and active, producing tenacious bonds through a thin pre-adsorbed protein-dominated "conditioning" film, that could be broken only by cohesive failure in the tissue itself. In contrast, the lower-surface-energy materials typical of standard dental implants were "walled off" by a cell-poor, nonadhesive capsule with a fibrous interface separated from a thicker "conditioning" film by a lipid-rich mucus zone. The advantages of proper surface treatment to favor the desired degree of biological adhesion are apparent.

1. Surface oxide favors adherence. The results of this study do not support the hypothesis that chromium oxide has a deleterious effect on adherence as measured by the torsion test. 2. Gritblasting the surface before porcelain application improves adherence. Smooth uncoated specimens where oxide was removed before enameling developed insufficient amounts of oxide for bonding. 3. The particular coating agent used on this study indirectly promotes adherence, since additional oxide forms during its application. Also, it may be directly involved by its influence on the residual stress distribution in the interface porcelain. 4. The more extensive the reaction zone at the interface, the further away the fracture surface is from the interface.

From 1982 to 1987, 22 patients with proven Pneumocystis carinii pneumonia were diagnosed at Wellington Hospital. Patients comprised 15 males and 7 females aged 15-76 years and included seven with AIDS, eight with haematological malignancy and seven with renal disease. Two distinct clinical prodromes occurred. In renal patients a classic fulminating pneumonitis developed over 24 to 72 hours. In patients with AIDS a more indolent illness occurred lasting 3 or more weeks and was characterised by fever, dry cough and breathlessness. Haematology patients showed no specific duration of prodrome. At the time of diagnosis all had an abnormal chest radiograph and the arterial PO2 was reduced in all but one case. An invasive diagnostic procedure was performed in all except one case where the diagnosis was made at post mortem. Two patients required a second procedure to establish the diagnosis. Procedures performed included bronchoalveolar lavage [14], open lung biopsy [7] and transbronchial lung biopsy [2]. All patients were treated with high dose cotrimoxazole and 18 survived to leave hospital. A review of the approach to the diagnosis and treatment of Pneumocystis carinii pneumonia is presented.

We previously have assigned N-terminal specificity to three hamster monoclonal antibodies (mAbs I, II, and III) produced to mouse recombinant gamma interferon (IFN-gamma), based on the ability of the N-terminal peptide IFN-gamma-(1-39) to block binding of 125I-labeled IFN-gamma (125I-IFN-gamma) and on the ability of these antibodies to bind 125I-IFN-gamma-(1-39). Only mAb I blocked function and binding to the IFN-gamma receptor, suggesting that it may bind to a region of the molecule involved in interaction with the receptor. To further define the epitope specificities of the antibodies, a series of N-terminal peptides were synthesized and tested for their ability to block antibody binding of 125I-IFN-gamma. Peptides IFN-gamma-(1-39), IFN-gamma-(1-20), IFN-gamma-(3-20), and IFN-gamma-(5-20) inhibited binding of 125I-IFN-gamma by mAb I in order of decreasing effectiveness, while peptide IFN-gamma-(7-20) was without effect. Peptides IFN-gamma-(1-39), IFN-gamma-(1-20), and IFN-gamma-(3-20) also inhibited binding of 125I-IFN-gamma by mAb II but were less effective when compared with their inhibition of mAb I. IFN-gamma-(5-20) and IFN-gamma-(7-20) did not inhibit binding by mAb II. Peptides IFN-gamma-(1-10), IFN-gamma-(10-30), and IFN-gamma-(21-44) did not inhibit either mAb I or mAb II. While IFN-gamma-(1-39) and IFN-gamma-(10-30) inhibited binding by mAb III, neither IFN-gamma-(1-20) nor any of its truncated forms were inhibitory. All three antibodies had similar Kd values for 125I-IFN-gamma. A prediction of the secondary structure of the molecule and the peptide inhibition data suggest that the epitope (possible receptor binding region) for mAb I involves a loop in the area containing residues 12-20, with sequences N-terminal to these residues possibly stabilizing the loop conformation. Direct evidence that the N-terminal 1-39 region of IFN-gamma is important in receptor binding was the observation that IFN-gamma-(1-39), but not the C-terminal IFN-gamma-(95-133), competed with 125I-IFN-gamma for the receptor on mouse L cells. IFN-gamma-(1-39) also specifically blocked IFN-gamma antiviral activity at concentrations that blocked binding to the receptor. The fact that IFN-gamma-(1-39) was the only peptide that blocked both IFN-gamma binding to receptor and function is consistent with the antibody competition data, where it was the most effective peptide in blocking binding of 125I-IFN-gamma by the N-terminal-specific mAbs. The combination of peptide mapping of epitope specificities and receptor competition should further help define the structural basis for IFN-gamma action.

Prior to implantation trials in animals, the effect of steam sterilization on the surface properties of metallic and coated biomaterials was studied. Pure germanium plates and cast surgical Vitallium discs and subperiosteal implants were treated to present three standard types of biomaterials surfaces prior to steam sterilization, ranging from scrupulously clean, high-energy metals to uniformly low-energy organic layers. Both before and after sterilization, the sample surfaces were characterized by a variety of nondestructive physiochemical techniques. The results indicate that steam sterilization is likely to compromise the properties of otherwise carefully prepared biomedical implants by depositing hydrophobic organic and hygroscopic salt contaminants over the implant surfaces.

This study tested the effect of Bredinin, a nucleoside antibiotic of fungal origin, on experimentally induced acute inflammation of the rabbit cornea. Inflammation was produced by abrasive removal of a 9 mm disk of corneal epithelium. In the dose-response experiments, one eye of each rabbit was treated topically with Bredinin, and the other eye with vehicle immediately after deepithelialization. The acute inflammatory leukocytes in tear film samples were counted at various times and the corneas were examined histologically at the end of the study. A paired t-test revealed that the numbers of acute inflammatory leukocytes after 5 hours were significantly less in the Bredinin-treated eyes, compared with the untreated eyes. The timing of drug-treatment was important; Bredinin was most effective in suppressing acute ocular inflammation when administered at, or within, one hour of the inflammatory stimulus. Histologic analysis demonstrated fewer acute inflammatory leukocytes on the ocular surface and in the stroma of the Bredinin-treated eyes, compared with the untreated eyes. No obvious corneal toxicity was noted, and the drug-treated eyes appeared less inflamed than the control eyes. The results of this study demonstrate the capacity of Bredinin to suppress the entry of inflammatory leukocytes into the tear film and suggest that this drug may have potential for use as a topical anti-inflammatory agent.

Eleven patients with progressive hairy cell leukaemia (three nonsplenectomised) were treated with recombinant alpha-2 interferon (Intron-A or Roferon-A) subcutaneously three times per week at a dosage of 3 x 10(6) units. Ten patients completed at least ten weeks of therapy and could be evaluated; one patient died of haemorrhage from severe thrombocytopenia after only three weeks treatment. Nine of the ten patients responded and all of these are regarded as good partial remissions (normalisation of all blood parameters but still discernible hairy cells in the marrow). Responding patients have all been followed for a median of two years and in one case 3 1/2 years since commencement of therapy. The patients are all transfusion independent and free of infection. We conclude that alpha-2 interferon therapy for progressive hairy cell leukaemia is effective therapy in both splenectomised and nonsplenectomised patients.

The deoxyuridine suppression test (DUST), performed on bone marrow cells, or peripheral blood lymphocytes, provides a rapid, dynamic assessment of vitamin B12 and folate status. The principles of this test are described and the use of the DUST in haematological practice at Wellington Hospital is reviewed. The advantages of the test are the speed of obtaining results, and an accurate assessment of the patient's condition when other haematological tests may be misleading.

The contention that erythropoietin (Epo) affects platelet production was investigated in the rat with recombinant human Epo (rHuEpo). In normal rats, Epo caused a dose-dependent increase in both reticulocyte and platelet numbers, the reticulocyte response preceding that of platelets. Withdrawal of Epo resulted in reticulocytes and platelets returning to control levels. [75Se]-selenomethionine incorporation into platelets was also enhanced in response to Epo. Chronic daily administration of rHuEpo resulted in steady state erythrocyte levels after 12 to 14 days, which were elevated 20% above controls. Attainment of this steady state was associated with both reticulocytes and platelets returning to control levels despite continued administration of Epo, an effect not associated with a change in the half-life of circulating Epo. In polycythemic rats a platelet response was observed before an effect on reticulocytes. Erythropoietin caused a 2.4-fold increase in the frequency of small acetylcholinesterase-positive cells within 24 hours, and increased the mean megakaryocyte diameter within 48 hours. Furthermore, the [3H]-thymidine labeling index of megakaryocytes from rats treated for 24 hours with rHuEpo was increased for all stages of megakaryocyte maturation. These results support the proposal of an effect of Epo on rat megakaryocytes causing increased platelet production.

The degree of bacterial contamination of 75 urine samples collected by voluntary voiding, catheterization, and cystocentesis was studied in 25 clinically normal dogs (14 females and 11 males) to evaluate the suitability of quantitative urine culture for diagnosis or urinary tract infection. Significant bacteriuria (greater than 100,000/ml) was not observed. Insignificant bacteriuria presumably caused by urethrogenital contaminants was detected in 44% of the urine samples collected by voluntary voiding, in 20% of the samples collected by catheterization, and in 12% of the samples collected by cystocentesis. The urine was sterile in 40% of the samples collected by voluntary voiding, in 80% of the samples collected by catheterization, and in 84% of the samples collected by cystocentesis. A bacteria count suggestive of bacteriuria (10,000--100,000/ml) was obtained in 1 sample collected by cystocentesis but was attributed to inadvertent penetration of a loop of intestine. Low bacteria counts were obtained in 4 (16%) samples collected by voluntary voiding, presumably as a result of urethrogenital and integumentary bacterial contaminants. It was concluded that urine samples properly collected from dogs by voluntary voiding, catheterization, or cystocentesis are suitable for detection of significant bacteriuria.

An examination of 380 patients was accomplished in order to determine the frequency of occurrence of pigmentary demarcation lines in an unselected population. Both white and black patients were included in the study, and there was an equal sex distribution. Separation of data by age groups enabled us to determine that the age of onset is in early childhood in the majority of cases. Seventy-nine percent of black female adults have at least one type of pigmentary demarcation line, with types A and B being present in over 50% of the cases. Seventy-five percent of black male patients had at least one pigmentary demarcation line, with type C being most prevalent. Fifteen percent of white female patients had one pigmentary demarcation line. Finally, it was determined that seven of fifty black women (14%) had the new appearance of type B lines with pregnancy.

Mean platelet volume, platelet count and platelet distribution width were determined in eight male subjects at monthly intervals over a 4-6 month period. Measurements were made on a Coulter S Plus VTM exactly 15 min and 2 h after blood collection. Long-term intra-individual variability for mean platelet volume showed a mean coefficient of variation (CV) of 1.60% at 15 min and 2.01% at 2 h after blood collection; for platelet count a mean CV of 3.18% at 15 min and 2.40% at 2 h; and for platelet distribution width a mean CV of 7.3% at 15 min and 6.5% at 2 h. Platelet parameters are stable over time in the normal male individual.

Studies have shown synthetic calcium phosphates such as hydroxyapatite and beta tricalcium phosphate to be biocompatible in vivo. However, few studies have quantitated histological responses to the implants. The aim of this study was to develop a method for the quantitative assessment of tissue biocompatibility to ceramic materials in vivo and to use this method to compare noncarbonated and carbonated apatite implants. Synthetic sintered apatites of 0, 3, and 6% carbonate by weight were prepared and cut into implants 4 X 4 X 1 mm. These were placed 2 mm into the medial aspect of rat femurs. Following sacrifice at 4 weeks, the femurs were fixed in formalin, demineralized in formic acid, and embedded in glycol methacrylate. Sections were cut on an ultramicrotome set at 1.5 micron and stained with toluidine blue. A point counting technique using standard stereological grids and a low-power microscope was used to measure areas of new bone formation. The width of the connective tissue zone adjacent to muscle was measured using an image analyzer. All implants were well accepted by the host tissues judging from criteria of minimal inflammation and degree of fixation. Results showed an increase in new bone formed in the marrow cavity with increasing carbonate content. This may improve stability of the implant in the host bone, particularly during the initial healing period. A technique which should enable quantitative histological evaluation of different ceramic materials has been developed. The use of this method indicates that further studies are warranted to investigate carbonated apatite as an implant material.

Different preimplantation surface finishes were applied to surgical vitallium discs and germanium prisms implanted for 20 days within the back muscles of adult rabbits. Histopathologic analysis of the numbers of nuclei of active fibroblasts immediately adjacent to the implants was carried out. The mean apparent volume fractions (MAVF) for the subdermal implant sites were found to depend on the surface cleanliness of the implant, the cleanest or highest-surface-energy surfaces giving the highest MAVF values for active fibroblasts.