Use of Dufour's gland secretion in nest defence and brood nutrition by hover wasps (Hymenoptera, Stenogastrinae)

Social wasps of the subfamily Stenogastrinae produce an abdominal secretion that is used in two distinct biological contexts. First, the secretion plays an important role in larval nutrition where it serves as a substrate in which food is placed by the adults for eventual consumption by the larvae. Second, in several species, females apply the same secretion to the substrate on which their nests are constructed, where it constitutes a sticky barrier that defends the immature brood from predation by ants. This paper describes for the first time ant guard construction behaviour of three species of stenogastrine wasps belonging to the genera Eustenogaster and Liostenogaster. The identification of compounds making up these secretions was also performed by gas chromatography-mass spectrometry. Ant guards and brood secretions were similar, with saturated and unsaturated long chain hydrocarbons and alcohols as major components. We further confirm that the glandular source of abdominal secretion is the Dufour's gland. This gland contains the same hydrocarbons, and in the same proportions as ant guards and brood secretion. We discuss the fundamental importance of Dufour's gland secretion in the social life of these wasps by comparing species with and without ant guards within the subfamily.

Ectal mandibular gland in Polistes dominulus (Christ) (Hymenoptera, vespidae): ultrastructural modifications over the secretory cycle

An ultrastructural study was carried out on the secretory activity of the ectal mandibular gland in the wasp Polistes dominulus (foundress and worker females as well as males). Secretory activity in foundresses proceeds slowly during hibernation and early spring, becoming prominent in late spring and then falling sharply during the summer. This sequential pattern of ultrastructural modifications follows a functional, annual cycle. However, by comparing the subcellular changes in the gland with colonial development, it appears that secretory activity fits in with the specie's social cycle rather than merely following the seasons. The highest levels of secretory activity correspond to the early, critical breeding phases, while activity slows down with an increase in colony protection, based on both primary (passive) and secondary (active) defenses, with the emergence of the workers. These correlations suggest that the ectal mandibular gland secretory product in P. dominulus is involved in chemical nest defense.

Antiandrogen drugs lower serum prostate-specific antigen (PSA) levels in hirsute subjects: evidence that serum PSA is a marker of androgen action in women

Assay by ultrasensitive methods of serum prostate-specific antigen (PSA) recently demonstrated that many women have detectable levels of this molecule. Interestingly, serum PSA concentrations were higher in hirsute than in nonhirsute subjects, suggesting that, also in females, PSA may be regulated by androgens. To establish the potential for this assay as a biochemical marker of androgen action in women, we studied 40 hirsute subjects recruited in a double-blind, placebo-controlled, 6-month trial assessing the effects of 3 different antiandrogen drugs: spironolactone, flutamide, or finasteride. In each subject, serum PSA, free testosterone, and 3alpha-androstanediol glucuronide were determined at baseline and at the end of treatments. At baseline, PSA concentrations were higher in these 40 women than in 19 nonhirsute healthy controls (12.9+/-1.5 vs. 4.9+/-0.7 pg/mL, P = 0.03) and significantly correlated with serum free testosterone (r = 0.37, P<0.005). After treatments, the 29 hirsute subjects given active drugs showed significant reduction of serum PSA levels (7.2+/-1.4 vs. 14.7+/-3.0 pg/mL, P = 0.002). This phenomenon was correlated to baseline PSA values. No change was found in the placebo group. In conclusion, serum PSA is increased in many hirsute women. A 6-month course of antiandrogen treatments with spironolactone, flutamide, or finasteride determines a reduction of PSA levels in these subjects. These results suggest that serum PSA is a biochemical marker of androgen action in tissues of female subjects.

Efficacy of 7 day lansoprazole-based triple therapy for Helicobacter pylori infection in elderly patients

BACKGROUND

The prevalence of Helicobacter pylori increases with age. However, data regarding the effects of anti-H. pylori treatments in the elderly are very scarce.

METHODS

To evaluate the effect of three lansoprazole-based, 7 day, triple-therapy regimens on H. pylori eradication rates, symptomatology, chronic gastritis activity and serological markers of H. pylori infection in elderly subjects, we studied 150 symptomatic patients over 60 years of age with H. pylori-positive duodenal ulcer (DU, n = 34), gastric ulcer (GU, n= 19) or chronic gastritis (CG, n = 97). Patients were consecutively treated with one of the following regimens: (A) lansoprazole (LNS) 30 mg b.i.d. + clarithromycin (CLR) 250 mg b.i.d. + metronidazole (MTR) 250 mg q.i.d.; (B) LNS 30mg b.i.d. + amoxycillin (AMOX) 1 g b.i.d. + MTR 250 mg q.i.d.; and (C) LNS 30 mg b.i.d. + CLR 250 mg b.i.d. + AMOX 1 g b.i.d.

RESULTS

Two months after therapy, the eradication rates of the three treatments, expressed using both intention-to-treat and per-protocol analyses were, respectively; group A, 86 and 91.5%; group B, 80 and 87%; group C, 82 and 89.1%. After therapy, a significant reduction in epigastric pain (P<0.001), heartburn (P=0.02), dyspepsia (P<0.001) and vomiting (P< 0.005) was observed independently of the success of H. pylori eradication. A significantly higher percentage of asymptomatic patients were in the GU-DU group than in CG group (87.7 vs 70.0%, P= 0.032). After therapy, 33 subjects still suffered from symptoms. Persistence of symptoms was significantly associated with an endoscopic diagnosis of oesophagitis and not with H. pylori infection. Patients cured of H. pylori infection showed a significant decrease in the histological activity of both antral and body gastritis (P< 0.0001), a significant drop in immunoglobulin (Ig) G anti-H. pylori antibodies (P< 0.0001) and pepsinogen (PG) C (P<0.0001) and an increase in the PGA/PGC ratio (P<0.0001).

CONCLUSIONS

The 7 day, lansoprazole-based triple therapy was well tolerated and highly effective in the cure of H. pylori infection, the reduction of symptoms, chronic gastritis activity and serum levels of IgG anti-H. pylori antibodies and PGC. Persistence of symptoms after therapy was significantly higher in CG than GU and DU patients and was significantly associated with oesophagitis.

Hemodynamic correlates of atrial natriuretic peptide concentration in unselected patients with heart disease of different etiologies

BACKGROUND

Although a large number of studies have investigated the relationship between atrial natriuretic peptide (ANP) concentrations and circulatory abnormalities, it is presently unsettled as to whether this parameter provides valuable information in unselected patients with heart disease of different etiologies regardless of the presence of left ventricular dysfunction or heart failure.

AIM OF THE STUDY

The aim was to evaluate the correlation between ANP, hemodynamics and parameters of ventricular function in a large series of consecutive patients and to define the predictive value of ANP for the identification of specific circulatory abnormalities.

METHODS

Cardiac catheterization was performed in 167 consecutive patients (62% males; mean age 62 yrs; range 18-85) and ANP serum levels were determined concomitantly by single antibody immune assay. Underlying etiology was: ischemic (67), valvular (72), idiopathic (12) and miscellaneous (16). Data management included: comparison of patients according to ANP values > or < 50% percentile of the cumulative distribution curve (i.e. 140 pg/ml); analysis of ANP concentrations according to the presence of normal or abnormal ventricular filling pressures; correlation between hemodynamic parameters and ANP concentrations; correlation of ANP with ventricular function in the whole population and in subgroups; calculation of sensitivity and specificity of ANP for the identification of abnormal filling pressures.

RESULTS

Mean ANP concentration was 181 +/- 139 pg/ml. Patients with ANP < 140 had significantly lower right-sided pressures but similar ventricular volumes and ejection fractions. By multivariate analysis, the single independent predictor of ANP was wedge pressure (p < 0.0001). Regarding etiology, severe mitral regurgitation was associated with the highest ANP levels (259 +/- 122 pg/ml), although the difference was not significant. The presence of abnormal left and right ventricular filling pressures was associated with significantly higher levels of ANP (p < 0.0001). A level of 125 pg/ml proved to be fairly sensitive (79%) but poorly specific (66%) for the detection of an abnormal wedge pressure. ANP was related to ventricular function only in the small subgroup of patients with dilated cardiomyopathy, where a significant negative correlation was found with both left ventricular (r = -0.72; p = 0.008) and right ventricular ejection fraction (-0.71; p = 0.01).

CONCLUSIONS

In unselected cardiac patients, ANP is confirmed to be a marker of left ventricular filling pressure in spite of poor specificity. Ventricular function appears to be related to ANP concentrations only in the subgroup of patients with pure heart-muscle disease.

Heterogeneity of the zona pellucida carbohydrate distribution in human oocytes failing to fertilize in vitro

The mammalian zona pellucida contains several glycoproteins whose oligosaccharide moieties are known to play a key role in the interaction with spermatozoa. Since zona pellucida defects may represent one of the most likely causes of failed fertilization in human in-vitro reproduction, we have studied the carbohydrate composition and distribution over the human zona pellucida by means of lectins. Donated, not inseminated cumulus-oocyte complexes, from cohorts with high fertilization rates, and fertilization-failed oocytes from cohorts inseminated with proven fertile donor semen, were analysed using 11 fluorescein-labelled lectins, on deplasticized semi-thin epoxy sections. Results showed that wheat germ agglutinin (WGA), Maclura pomifera (MPA) and Pisum sativum (PSA) bound to the extracellular matrix bordering the zona pellucida-corona radiata interface of cumulus-oocytes complexes, while the zona pellucida was labelled by WGA, Concanavalin A (ConA) and PSA. WGA labelling and correlative electron microscopy on the cumulus-oocyte complexes demonstrated that this lectin is a useful tool to trace the cortical granule distribution in the human oocyte. Surprisingly, in the failed-fertilized oocytes the zona pellucida was also labelled by MPA and showed three different patterns: (i) labelling of the zona pellucida outer surface; (ii) uniform labelling; (iii) labelling of an outer zona pellucida layer with variable thickness. Comparative analysis of WGA and MPA labelling on single failed-fertilized oocytes demonstrated that MPA zona pellucida patterns are not related to the cortical reaction. The nature and meaning of the MPA pattern of failed-fertilized oocytes were discussed in the light of zona pellucida defects impairing sperm receptivity.

Beta 2-microglobulin removal by synthetic dialysis membranes. Mechanisms and kinetics of the molecule

Beta 2-microglobulin (beta 2-m) accumulation represents a possible complication of long term dialysis. It is therefore important to evaluate the capacity of removal of this molecule from the patient by different dialysis membranes. The present study is aimed at evaluating the mechanisms involved in beta 2-m removal by three different synthetic membranes: a) highly asymmetric hydrophobic polysulfone (Biosulfane, NMC), b) moderately asymmetric and hydrophobic polysulfone (PS600, Fresenius), c) Polyacylonitrile (AN69HF, Hospal). The adsorption capacity and sieving coefficients of the three membranes for native and labeled beta 2-m were studied in vitro utilizing human blood. The amount adsorbed by the membrane was measured by the elution of the molecule obtained with a detergent solution. Clearances, total removal and membrane adsorption were studied in six patients treated in a randomized sequence with the three membranes. For this purpose, plasma and dialysate measurements as well as total collection of spent dialysate and beta 2-m elution from the used dialyzers were carried out. Ex novo generation of beta 2-m did not take place during in vitro circulation. The molecule was removed by the studied membranes both by filtration and adsorption. The Biosulfane membrane removed beta 2-m mostly by adsorption while the PS600 membrane removed beta 2-m almost entirely by filtration. Intermediate behaviour was shown by AN69 membrane. Similar quantities of beta 2-m were removed from the patients with the three membranes. Total removal could only be precisely measured by adding the quantity of beta 2-m eluted from the membrane to the amount recovered in the spent dialysate. Out of total removal, adsorption was more than 90% with Biosulfane, while only 5% with the PS600. These findings contribute to the understanding of the discrepancy found between the clearance measured from the plasma side and that measured from the dialysate side. In conclusion, clearance and sieving measurements for beta 2-m cannot be correctly performed unless the capacity of adsorption of the membrane is taken into account.

Culture of fetal erythroid progenitor cells from maternal blood for non-invasive prenatal genetic diagnosis

Fetal committed erythroid progenitors CFU-E and M-BFU-E released into the maternal circulation during pregnancy are ideal candidates for in vitro proliferation since their lifespan is short and they can form colonies of 100-1000 cells in a semi-solid medium. In order to propagate these cells with a high rate of purity, a strategy was devised based on their prior enrichment with biotin-labelled human erythropoietin ligand and magnetic sorting before culturing in a suitable medium. Eight euploid pregnancies investigated in order to address this issue produced fetal clones in cultures with 18 per cent purity as assessed by polymerase chain reaction (PCR) analysis for Y-specific sequences, immunocytochemical staining for fetal gamma-globin, and fluorescence in situ hybridization (FISH) study. The CFU-E-type colony was the most represented progenitor, followed by M-BFU-E, and only occasionally was the detection of CFU-GEMM recorded. The retrospective diagnosis of two cases of fetal Down's syndrome by culturing fetal cells from maternal blood was accomplished for the first time. FISH analysis disclosed a strong presence of fetal trisomic cells (70 per cent and 40 per cent in the two cases). This strong presence would suggest a preferential leakage into maternal blood. The overall results of this study demonstrate that fetal cells can be cultured in vitro with reliable reproducibility, thus making the prospect of a non-invasive prenatal genetic diagnosis realistic.

A soluble sperm factor gates Ca(2+)-activated K+ channels in human oocytes

PURPOSE

Our goal was to study the activation current in physiologically competent metaphase II human oocytes, i.e., not previously exposed to spermatozoa or aged in vitro, and, in particular, to determine whether a soluble sperm factor triggers a fertilization current comparable to that observed with intact spermatozoa and to characterize the current involved.

METHODS

The whole-cell voltage-clamp technique was used on spare metaphase II oocytes, obtained with patient consent from IVF programs. In this configuration a soluble fraction from human spermatozoa was microinjected, and the current recorded.

RESULTS

Metaphase II human oocytes generate bell-shaped outward currents of 400-1000 pA (X = 706 +/- 322; n = 10), following injection of a cytosolic extract from human spermatozoa. The amount of sperm extract injected was less than 10% of the total oocyte volume and was equivalent to 1-10 spermatozoa. A similar current was generated following exposure to 20 microM of the calcium ionophore A23187 (n = 10). The steady-state conductance of the oocyte increased from 10 to 19.8 nS (n = 10) following injection of the sperm factor and from 5.3 to 27.7 nS following ionophore exposure. Both sperm factor- and ionophore-induced currents were reduced in amplitude when the unfertilized oocyte was preexposed to 25-75 microM iberiotoxin (n = 8) and eliminated at a concentration of 100 microM iberiotoxin.

CONCLUSIONS

The data support the hypothesis of a soluble sperm factor involved in the activation of human oocytes and shows that the initial activation response in the human oocyte is the gating of Ca(2+)-activated K+ channels.

[Acute changes in the hemodynamic profile and circulating levels of atrial natriuretic peptide induced by dobutamine in severe heart failure]

METHODS

Sixteen patients (15 males, 1 female; mean age 63 years, range 45-78) with severe heart failure (NYHA class III = 5; class IV = 11) secondary to ischemic heart disease (8), dilated cardiomyopathy (5) and valvular heart disease (3), were evaluated for eligibility to intermittent Dobutamine (D) treatment. As a part of this evaluation, they were submitted to an acute dose-ranging test with D, up to 10 micrograms/Kg/min under hemodynamic and electrocardiographic monitoring. By inclusion criteria, all patients had:-cardiac index (CI) < 2.2 L/min/m2;-pulmonary wedge pressure (WP) > 18 mmHg;-left ventricular ejection fraction (EF) < 30%. At each step of the procedure, hemodynamic measurements and blood sampling for atrial natriuretic peptide (ANP) concentration were performed.

RESULTS

Peak effect, defined as the dose corresponding to the maximum increase in CI, was reached at a mean of 7.8 +/- 0.5 micrograms/Kg/min. CI increased from 1.7 +/- 0.3 to 2.53 +/- 0.7 L/min/m2 (p < 0.001) and ANP decreased from 234 +/- 112 to 173 +/- 118 pg/ml (p < 0.001). Correspondingly, heart rate, stroke volume index and stroke work index increased, while right atrial pressure (RAP), mean pulmonary artery pressure (PAP), WP, systemic and pulmonary vascular resistance all significantly decreased. Mean arterial pressure was not affected. Changes in ANP concentration correlate significantly with changes in WP and in PAP (r = 0.65, p < 0.05 and r = 0.89, p < 0.001, respectively), but not with changes in RAP (r = 0.26, p = 0.34). Patients showing an increase > 40% in CI or a CI > or = 2.5 L/min/m2 at peak effect (responders) had significantly lower baseline PAP with respect to non-responders. Besides PAP, baseline ANP levels, end-systolic pressure/volume ratio and ejection fraction were also independent predictors of response. The test did not induce complex arrhythmias and was well tolerated in all patients.

CONCLUSIONS

Patients with severe heart failure retain the ability to respond to acute administration of D. with a significant improvement in their hemodynamic profile. Response to D. administration is predicted by lower baseline pulmonary pressure and ANP levels and a lesser degree of left ventricular dysfunction. Despite high baseline ANP concentration, a significant decrease is obtained which parallels the decrease in pulmonary artery and pulmonary wedge pressure, but is not related to changes in right atrial pressure. These findings suggest that changes in left ventricular performance induced by D. are the major determinants of the decrease in ANP concentration in this clinical setting.

Helicobacter pylori infection in asymptomatic elderly subjects living at home or in a nursing home: effects on gastric function and nutritional status

Age and close living conditions are known to be risk factors for the acquisition of Helicobacter pylori (HP) infection. It is unknown whether institutionalization of asymptomatic, elderly subjects is an additional risk factor and whether gastric function and nutritional status are affected by the HP infection. The study sample comprised 102 subjects over 65 years of age: 52 living in a nursing home and 50 at home. No subject had symptoms or previous pathology related to the upper digestive tract. In all subjects, serum levels of specific anti-HP antibodies were determined. Gastric function was evaluated by levels of pepsinogen A (PGA), pepsinogen C (PGC) and gastrin. The nutritional status of the subject was evaluated by measuring: albumin, haemoglobin, iron, ferritin, transferrin, vitamin B12, and folic acid in blood, and body mass index and mid-arm muscle area. The prevalence of anti-HP antibodies was 86.5% in institutionalized subjects (men: 100%; women:76.6%, p <0.05) and 82.0% in subjects living at home (men:86.3%; women:76.3%). No differences between the two groups were observed in levels of serum anti-HP antibodies and PGC was identified. In neither group were differences observed between serum positive (HP + ve) and negative (HP - ve) subjects with respect to the biohumoral and anthropometric indices of nutritional status. We conclude: (1) the seroprevalence of the HP infection was high (82-86%) in asymptomatic elderly patients living either at home or in an institution; (2) the presence of specific IgG anti-HP antibodies in asymptomatic elderly individuals, at home or in a nursing home, was not associated with changes in PGA levels in institutionalized subjects; (3) nutritional indices were not influenced by the presence of anti-HP antibodies.

Vasopressin, atrial natriuretic factor and renal water homeostasis in premature newborn infants with respiratory distress syndrome

Arginine vasopressin (AVP), human atrial natriuretic peptide (hANP), and body fluid and electrolyte balance were examined during the first five days of life in eleven premature infants (birthweight 1610 +/- 240 g, gestation 30 +/- 1 weeks) receiving mechanical ventilation for respiratory distress syndrome (RDS). Plasma hANP and urine AVP concentrations were determined by radioimmunoassay on the first, third and fifth days. Arginine vasopressin urine levels remained constantly elevated during the study period (mean +/- SD 13.5 +/- 7.8 day 1, 12.0 +/- 9.9 day 3, 13.2 +/- 5.1 ng/l day 5, p = n.s.), while plasma hANP was significantly increased on the third day (626 +/- 495 vs. 298 +/- 240 pg/ml on day 1, p < .05). Urine sodium concentration, urine osmolality and osmolality and osmolar clearance were elevated significantly as well on day 3, p < .05, and correlated to hANP levels. Body weight decreased during the study by 8.2% on the third day and by 11.3% of birthweight on the fifth day. A significant increase in creatinine clearance occurred after the third day (p < .01), while free water clearance remained essentially the same during the first five days of life. We speculate that an increase in plasma hANP concentration on day 3 of life results in a natriuresis and osmolar diuresis without correlations or temporal relationships to hypervasopressinemia of the premature neonate with RDS.

Tumor markers in breast cancer follow-up: a potentially useful parameter still awaiting definitive assessment. Forza Operativa Nazionale sul Carcinoma Mammario (FONCaM)

BACKGROUND

Although tumor markers are frequently used in the follow-up of patients with breast cancer, two points are still being debated: 1) their cost/effectiveness has been neither demonstrated nor disproved; 2) the reliability of the currently used dichotomous division into a positive/negative cut-off should be definitely validated. Dynamic criteria of interpretation based on serial serum samples would probably be more effective for early detection of relapse.

PATIENTS AND METHODS

The aim of the present study was to compare the dichotomous cut-off based decision criteria to a dynamic serial sample based assessment of tumor markers. Since 1989, 794 patients have been followed in 11 institutions. CEA and CA15.3 were measured once a month for three months before every clinical examination. The present paper concerns the evaluation variability in 405 patients without evidence of disease in the first three institutions joining the study.

RESULTS

In patients without evidence of disease, the coefficient of variation of all samples for every patient showed a median value of 19 for CEA and 21 for CA15.3. Variability was negatively associated with the antigen level and was most likely due to the analytical component. This was also confirmed by the significant difference in variability among the three institutions evaluated. The median value of the critical difference was 53% for CEA and 57% for CA15.3.

CONCLUSIONS

1) Individually tailored dynamic decision criteria are applicable in about 50% of the cases. 2) The problem of improving the precision of tumor marker assays in the low dose range must be urgently addressed to the manufacturers of tumor markers by the scientific community in order to apply individually tailored decision criteria for patients in whom the serum level of biological markers is low.

A morphological and functional study of fusibility in round-headed spermatozoa in the human

OBJECTIVE

To study the molecular origin and functionality of the plasma membrane of round-head spermatozoa in the human.

DESIGN

Clinical and laboratory study.

SETTING

Patients in a clinical and academic environment.

PATIENTS

Men with round-head spermatozoa.

RESULTS

Pisum sativum lectin homogeneously stains the surface of round sperm; however, the staining pattern and transmission electron microscopy show that the plasma membrane does not alter after exposure to the calcium ionophore A23187. In a clinical program, round-head spermatozoa injected subzonally into metaphase II oocytes with or without pretreatment with the fusogen polyethylene glycol did not bind or fuse to the oocyte surface.

CONCLUSION

The data suggests that plasma membrane fusion in human gametes is regulated by specific surface molecules and that exposure of these molecules on the sperm surface cannot be triggered by elevating intracellular calcium alone.

Single umbilical artery: a Doppler flow velocity study of four cases

We measured the pulsatility index of the umbilical artery in four fetuses identified as having a single umbilical artery. A pulsed color Doppler ultrasound machine was used and measurements were performed at 4-week intervals following the first diagnosis of single umbilical artery (week 22-34). The pulsatility index was derived from the mean of five consecutive measurements at the umbilical insertion of the cord, taking care to obtain the Doppler signal with an incidence angle between +45 degrees and -15 degrees. All measurements were taken during periods of fetal inactivity. The pulsatility index at 22, 26, 30, 34 and 38 weeks in these pregnancies did not differ significantly from the mean values registered in normal pregnancies. The four women gave birth to babies of normal weight: two were healthy, one suffered from bladder extrophy and hemispondyly, the other had bilateral dilatation of the renal pelves, megalocystis, megalourethra and an imperforate anus.

Variability of tumor markers in the follow-up of patients radically resected for breast cancer

The biological and analytical components of variability of tumor markers should be distinguished from the variations due to tumor progression. The aim of the present study was to evaluate tumor marker variability in the follow-up of patients resected for breast cancer. So far, we have carried out 2,085 CEA and 2,550 CA 15-3 determinations in 435 patients. The total variability of both CEA and CA 15-3 was widely scattered among different subjects (CEA coefficient of variation 0-105%; CA 15-3 coefficient of variation 0-89.2%). The biological variability of CA 15-3, which was calculated in a limited number of cases, was scattered between 0 and 23% and was higher than the intra-assay variability. From these findings we conclude that when evaluating serial marker assays the intra-individual variability should be assayed initially to obtain a reference value of individual variability in relapse-free conditions.

Anti-Thy-1 antibody responses evoked by Thy-1 antigen expressed in transfected mouse mastocytoma cells and rat fibroblast

The mouse genomic Thy-1.1 gene was isolated from a phage library constructed from AKR/J (Thy-1.1) mouse DNA. Partial nucleotide sequence analysis of the coding region showed that it has only a single nucleotide difference from the Thy-1.2 gene, namely that amino acid 89 reads CGA (Arg) in Thy-1.1 and CAA (Glu) in Thy-1.2, corresponding to the amino acid substitutions previously identified. It was subcloned into an SV-40 derived vector for transfection. Transient transfection into HeLa cells gave 2% positive staining by immunofluorescence. The gene in this vector was also co-transfected into L cells and mastocytoma cells (both of Thy-1.2 strain origin) together with the Agpt gene. L-cell clones selected for transformation proved almost negative for Thy-1.1 expression, and any positive clones gradually lost Thy-1.1 antigen expression in culture. On the contrary, all clones of mastocytoma transformants gave a high level of expression after more than 3 months in culture. The mastocytoma transformants were used to study the immunogenicity of Thy-1.1 molecules expressed on transfected cells. They evoked clear anti-Thy-1.1 plaque-forming cell (PFC) responses both in vivo and in vitro. The mastocytoma transformants also proved able to induce a T-dependent anti-Thy-1.1 antibody response in a cell transfer experiment. The immunogenicity of Thy-1.2 molecules on rat fibroblasts was also studied after transfection with a Thy-1.2 gene cosmid. Although Thy-1.2 expression was very low, these transfectants elicited a clear anti-Thy-1.2 PFC response from AKR spleen cells hyperimmunized against CBA thymocytes.

[Myelofibrosis caused by cancer: presentation of a clinical case with a very difficult diagnosis]

Fibrosis of the bone marrow or myelofibrosis, is a connective tissue response of the bone marrow, giving rise to alterations of various nature. From an etiological point of view, it may be divided into primitive or secondary forms. Since the therapeutic implications differ, it is important to make a correct differential diagnosis between the 2 forms. With this in mind, particular importance must be given to myelofibrosis secondary to neoplastic metastasis since it frequently presents with a clinical and hematological picture and bone marrow morphology typical of acute or chronic idiopathic myelofibrosis. In such a situation the particular course of the disease and the description fibrosis-sclerosis of the bone marrow are highly suggestive of myelofibrosis secondary to neoplastic metastasis. On the basis of these considerations, we found it interesting to report a case which came under our observations. The patient in this case presented a complex differential diagnosis which offered us the occasion to review and highlight the clinical and histological criteria fundamental to the 2 forms. The patient, a 40 year old woman, presented with a clinical picture typical of myelofibrosis following surgery for a cystic ovary. For 3 years she had felt violent bone pains and had progressively declined in her physical state to the point of cachexia. A careful histological exam of the bone marrow revealed metastasis from the gastric tumor thus giving a clear diagnosis of secondary myelofibrosis.