First Measurement of a Long-Lived π

The adapted DIRAC experiment at the CERN PS accelerator observed for the first time long-lived hydrogenlike π^{+}π^{-} atoms, produced by protons hitting a beryllium target. A part of these atoms crossed the gap of 96 mm between the target and a 2.1 µm thick platinum foil, in which most of them dissociated. Analyzing the observed number of atomic pairs, n_{A}^{L}=436_{-61}^{+157}|_{tot}, the lifetime of the 2p state is found to be τ_{2p}=(0.45_{-0.30}^{+1.08}|_{tot})×10^{-11} s, not contradicting the corresponding QED 2p state lifetime τ_{2p}^{QED}=1.17×10^{-11} s. This lifetime value is three orders of magnitude larger than our previously measured value of the π^{+}π^{-} atom ground state lifetime τ=(3.15_{-0.26}^{+0.28}|_{tot})×10^{-15} s. Further studies of long-lived π^{+}π^{-} atoms will allow us to measure energy differences between p and s atomic states and so to discriminate between the isoscalar and isotensor ππ scattering lengths with the aim to check QCD predictions.

Observation of π

The observation of hydrogenlike πK atoms, consisting of π^{-}K^{+} or π^{+}K^{-} mesons, is presented. The atoms are produced by 24 GeV/c protons from the CERN PS accelerator, interacting with platinum or nickel foil targets. The breakup (ionization) of πK atoms in the same targets yields characteristic πK pairs, called "atomic pairs," with small relative momenta Q in the pair center-of-mass system. The upgraded DIRAC experiment observed 349±62 such atomic πK pairs, corresponding to a signal of 5.6 standard deviations. This is the first statistically significant observation of the strange dimesonic πK atom.

Giant coronary artery aneurysm in association with systemic arterial ectasia. A case report.

Since the advent of coronary angiography, coronary artery aneurysm has been diagnosed with increased frequency. The etiology of coronary artery aneurysm is atherosclerosis in 50%, followed by other causes. In a 71-year-old man with previously documented abdominal aortic aneurysm of 6 cm diameter and ectasia of both left and right middle cerebral arteries, thoracic magnetic resonance imaging (MRI) demonstrated a large hollow para-cardiac mass (maximum diameter of 7 cm) lying in the anterior-lateral part of the atrio-ventricular sulcus. Coronary arteriography confirmed the aneurysmatic nature of the proximal tract of left anterior descending (LAD) artery lesion. Screening for laboratory signs of vasculitis was negative and other vascular and systemic diseases were excluded, suggesting an atherosclerotic aetiology of the aneurysm. In the absence of current cardiac symptoms, conservative management has been chosen and the patient is still well 2 years after presentation.

Arthropathies and thyroid diseases.

AIM: Improvement of articular symptoms following thyroidectomy has often been observed in patients with an association of thyroid and joint diseases. An assessment has therefore been made of the types of arthropathy thus benefited and the anatomopathological features of the thyroid in patients with concomitant joint diseases. An account is given of the arthropathies associated with nontoxic nodular goitre (NTG). METHODS: Three cell markers are examined to identify immunocytokine elements differentiating thyroid diseases. RESULTS: Immunohistochemical examination shows extravasal lymphocyte infiltrates; thyrocytes were negative for HLA-Cl II, CD38 and IL-6R, and only dim-positive for HLA-Cl I. Endothelial cells were positive for HLA-Cl I and II and CD38, and negative for IL-6R. The lymphocyte were positive for HLA-Cl I, HLA-Cl II and CD38, but negative for IL-6R. The follow-up of 6 thyroidectomised patients disclosed improvement in joint pain and remission of rheumatoid arthritis and spondylarthritis. Association of nodular goitre with arthro-pathies is demonstrated. CONCLUSION: Arthritis and arthralgia are frequent in patients with thyroid diseases, we particularly found the association with MHNG and Hurthle cell adenoma. Arthritis and arthralgia quickly improve after thyroidectomy. Immunohistochemical NTG thyrocytes are still normal cells (HLA-Cl II negative) by contrast with their HLA-Cl II positivity in autoimmune thyroiditis.

[Pruritus. Physiopathology, clinical features, and treatment]. / Il prurito. Fisiopatologia, clinica e terapia.

Pruritus is a subjective disturbance that accompanies many dermatological, allergic and internal medicine disorders. It may well be the only symptom that leads a patient to consult a doctor. In situations of this kind, the cause of the complaint is very hard to determine and the tests employed often fail to give a clear-cut answer. This paper stresses the complexity of the hypotheses advanced to illustrate the pathogenesis of pruritus and reviews its many chemical mediators. An account is also given of the pathogenetic pointers that can be drawn from the conditions, including some within the compass of internal medicine, most commonly associated with pruritus and taken into consideration in the planning of individual treatment regimens.

Measurement of specific IgEs in the diagnosis of drug allergy.

BACKGROUND: The anamnesis and, in certain cases, skin tests are indispensable methods for the correct diagnosis of allergy to drugs. However, in some cases, these two techniques alone, prove insufficient in achieving reliable predictive elements for drug allergies. Besides, the use of skin testing is often discouraged, due to the potential risks involved. METHODS: In this study, the diagnostic efficiency of the measurement of specific IgE for a selected group of 13 drugs was evaluated. The test was carried out on 96 patients showing clinical signs directly attributable to the administration of one particular drug (in 38 of the 96 cases) or more drugs (58/96 cases). The symptoms appeared after a week or more from the beginning of the drug treatment; this time interval is compatible with the development of an immune response. RESULTS: The drugs most frequently causing adverse reactions were salicylic acid, noramidopyrin, propiphenazone, other non-steroidal anti-inflammatory drugs (NSAIDs), trimetoprim, antibiotics. RAST was applied to 13 drugs and was positive for at least one of the drugs tested in 31/96 patients. CONCLUSIONS: The results of the study confirm the validity of the RAST technique as a useful element in improving and making the overall diagnosis of allergies to drugs more reliable.

Bronchial reactivity in subjects with urticaria.

BACKGROUND: Respiratory symptoms (rhinitis, asthma) accompany some skin diseases with a proven immunological or allergic pathogenesis whereas the immunological and allergological findings are sometimes negative in subjects with chronic urticarial skin symptoms and no cause can be found. This paper explores the possibility of airway inflammation in cases of this kind. METHODS: Nonspecific bronchostimulation with methacholine was carried out in 12 subjects with a clinical history of urticaria and negative immunological and allergological findings. RESULTS: All subjects displayed normal bronchoreactivity (mean PD20 1400 micrograms). The bronchostimulation test (evaluated from the FEV1) was always negative. In the control group the mean PD20 was 720 micrograms. CONCLUSIONS: The fact that these eleven subjects did not display bronchial hyperreactivity suggests that monitoring of their respiratory function is not required.

[Transient immunosuppression after abdominal surgical intervention]. / Immunodepressione transitoria dopo intervento chirurgico addominale.

Transient immunodepression appears a few hours after surgery and usually regresses spontaneously within 15-20 days. In this study, cellular and humoral immunity parameter values were compared prior to and 24 h, 7 days and 14 days after laparotomic and laparoscopic cholecystectomy (12 patients and 25 patients respectively) operated at the University of Turin's First Surgical Clinic, to look for differences in the immunological effects of these two types of surgery. The following parameters were determined: IgG, IgA, IgM, C3, C4, granulocytes (CD11c), lymphocytes, B lymphocytes (CD19, CD19-CD15), T lymphocytes (CD3), T helper cells (CD3-CD4), T suppressor cells (CD3-CD8), CD4/CD8 ratio, NK cells (CD16), monocytes (CD14, CD11c-CD14), IL-2 receptor expression (CD25), HLA-DR expression (total HLA-DR, HLA-CD3), total cytotoxic activity (CD57), T cell cytotoxic activity (CD8-CD57), and NK cell cytotoxic activity (CD16-CD57). Granulocytes increased significantly (p < 0.05) in both groups. The increase was more marked in the laparotomy group and still evident on the 7th and 14th days. Total T cells, T helpers and NK cells fell after 24 h (p < 0.05) in this group only. These results suggest that laparoscopy is associated with less substantial immunological changes than laparotomy.

Undefined CD4 lymphocytopenia without clinical complications. A report of two cases.

A form of idiopathic CD4 lymphocytopenia (ICL) has been recently described. Its diagnostic criteria have been defined by the Centers for Disease Control (CDC), Atlanta. Associations of ICL with hepatitis C infection have been reported, while some ICL patients have presented abnormalities partly similar to those observed in common variable immunodeficiency (CVI). This paper illustrates the immunological pictures of two subjects with a CD4 deficiency confirmed in a series of peripheral blood lymphocyte subset determinations, but not associated with other cellular or humoral immunity abnormalities and accompanied by poorly significant clinical manifestations (no opportunistic infections). Patient one has been observed for a very long period. Her serological picture has been negative and she is free from hypergammaglobulinemia. HIV infection can thus be ruled out. Patient two has not required any specific treatment so far. The CDC's diagnostic criteria for ICL are not fully met in the two cases. Their pictures meet many, though not all of the CDC criteria for the diagnosis of ICL. It is to be hoped that a protracted follow-up will allow an assessment to be made of the natural history of the two cases.

[Immunologic aspects of allergic and non-allergic asthma]. / Aspetti immunologici dell'asma allergico e non allergico.

METHODS: The peripheral blood lymphocytes and lung function have been studied in 25 patients: 12 affected by atopic asthma and 13 affected by non atopic asthma. RESULTS: The results obtained indicate that peripheral blood CD3 and CD4 cell as well as HLA-DR marker are higher in the extrinsic asthma group. CONCLUSIONS: These findings confirm that an active inflammatory process exists in the group of non-atopic and functionally more compromised patients.

[Components of complement in patients with immediate hypersensitivity]. / Il complemento in soggetti con ipersensibilità immediata.

BACKGROUND: This prospective study was undertaken to assess the differences between the levels of the main plasma components of complement in allergic subjects and in those with pseudoallergic clinical manifestations. METHODS: Plasma C3 and C4 were evaluated in a total of 256 subjects examined consecutively at the allergology outpatients clinic of the Internal Medicine Division B, University of Turin. Total IgE and C1-inhibitor levels were also determined in 128 and 44 subjects respectively. RESULTS: C3 and C4 levels were not significantly different (p = 0.398 and p = 0.497) in 123 subjects with a positive and 133 with a negative prick test, nor in allergic subjects with respiratory as opposed to skin symptoms (p = 0.293 and p = 0.462), whereas the C-1 inhibitor was significantly lower (p = 0.046) in the respiratory subgroup. Total IgE was positively correlated with the C3 level (p = 0.036) in 75 allergic subjects. CONCLUSIONS: These findings suggest that plasma C3 and C4 values are not sufficient to discriminate IgE inflammation (positive prick test) and pseudoallergy (negative prick test) in the assessment of subjects with clinically suspected allergy. The positive correlation between IgE synthesis and C3 also points to an interaction between IgE synthesis and C3 regulation proteins in patients with IgE mediated diseases. Further investigation of other acute phase proteins (C reactive protein, fibrinogen) and the cytokines regulating their synthesis (IL-6) in such patients will help to clarify this correlation.

[Muscle fatigue and dyspnea]. / Fatica muscolare e dispnea.

Calm breathing requires little effort on the part of the inspiratory muscles to overcome the elastic and non-elastic resistances of the chest-lung system. Spontaneous expiration is passive and does not engage the respiratory muscles. In the event of restriction or obstruction, however, there are changes in these two types of resistance and their distribution. Extra work is required and the blood flow through the muscles has a decisive influence on their performance. Histologically detectable differences in the number of fast or slow, glycolytic or oxidative fibres in the respiratory muscles correspond to functional differences. Some muscles are required to supply the force or energy of contraction, others are concerned with endurance and others with intermediate situations. The diaphragm is mainly composed of slow-oxidative fibres. It is thus characterised by its strength, low tension, high repetitive capacity and incredible endurance. This brief review describes the main concepts of the physiology of the respiratory muscles. Reference is also made to the mechanisms of muscle fatigue and dyspnea, two independent or associated clinical situations that point to the risk of progression to respiratory insufficiency.

[CD4 lymphocytopenia in patients without significant clinical pathology]. / Linfocitopenia CD4 in pazienti senza significativa patologia clinica.

There are different causes of CD4 lymphocytopenia: neoplastic pathology, immunosuppressive therapy or other iatrogenic forms. In addition to these causes, an important role is certainly played by HIV infection which, at the AIDS stage, constantly accompanies progressive CD4 lymphocytopenia, with or without affecting the other lymphocyte components. CD4 lymphocyte deficits not correlated to HIV infection are relatively rare and are not always accompanied by progressive clinical manifestations of immunodeficiency. In the recent past an idiopathic form of CD4 lymphocytopenia (ICL) was recognised whose diagnostic criteria were defined by the Center for Disease Control (CDC) in Atlanta. Cases of ICL association with hepatitis C virus infection have been reported and anomalies partially shared by subjects suffering from common variable hypogammaglobulinemia (CVH) have been reported in some ICL carriers. The CD4 deficit in these patients is not associated with other cellular and/or humoral immunological anomalies and the clinical manifestations, essentially of scant importance, have not shown signs of progression towards severe immunodeficiency syndromes. The authors report 4 subjects with major CD4 deficit whose clinical characteristics do not match idiopathic lymphocytopenia and specific serological tests have excluded HIV infection. No known causes of CD4 lymphocytopenia have been found in these patients and they do not present major signs of clinical damage.

[Effect of specific immunotherapy on peripheral T-lymphocytes in atopic patients]. / Influenza dell'immunoterapia specifica sui linfociti T periferici in pazienti atopici.

Specific hyposensitising therapy for IgE mediated respiratory allergopathies is recognised as an effective therapy able to improve clinical symptoms and bronchial hyperreactivity. IgE synthesis, which is altered in atopic subjects, is regulated by CD4 and partly CD8 lymphocytes. This paper examines the changes in the main T lymphocyte subpopulations in peripheral blood in 10 atopic subjects undergoing specific immunotherapy. The results highlight a significant reduction (p = 0.028) in mean CD4 levels after 6.3 months of treatment. Changes in the other T lymphocyte components and total IgE serum levels were not significant.

[Diagnosis of drug allergy. Role of specific IgE and IgG determination]. / Diagnosi di allergia ai farmaci. Ruolo del dosaggio di IgE e IgG specifiche.

In the diagnosis of drug allergies, the anamnesis and, in some cases, prick tests are without doubt indispensable approaches but they are not always able to provide optimal prognostic levels. Moreover, prick tests are sometimes contraindicated owing to their potential danger. This study evaluated the diagnostic efficacy of a test in vitro--the assay of IgE- and IgG-specific (RAST)--for a group of 16 drugs in 88 patients referred for allergological consultancy after clinical manifestations attributable to the administration of a drug (30/88 cases) or more than one drug (58/88). Disorders had appeared at least one week after the start of drug treatment, an interval that is compatible with the development of an immune response. In 17/88 (19.3%) patients the in vitro test confirmed the presence of IGe and/or IgG against at least one of the drugs suspected in the anamnesis. In this series it was also found that there was a higher incidence of ADR in females (60/88) compared to males (28/88). Reactions to several drugs were more frequent than reactions to a single drug (58 cases vs 30). The association of ADR and the presence of other allergies in a particular individual was relatively rare (13/88 = 14.7%). These results confirm the value of RAST as a useful aid to improve the overall diagnosis of drug allergies and to make it safer.

Bal T lymphocyte subsets are reduced in primary lung neoplasias.

Direct observation with an optic fibre bronchoscope facilitates the diagnosis, staging and treatment of both neoplastic and other lung diseases, and the varying diameters available enable IVth or even Vth-order bronchi to be examined. The technique can be employed for deep lung lavage or bronchoalveolar lavage (BAL) and for transbronchial biopsy. The BAL fluid, too, can be used to study lung cells and soluble components. In this study, 21 patients aged 32-79 (mean 55.5), namely 16 with lung cancer and with non-neoplastic lung diseases, were subjected to BAL to allow a study to be made of the BAL fluid cell composition. In the neoplastic group, CD3 lymphocytes were 41.3% compared with 63.2% in the peripheral blood. CD4 (24.6% vs 40.6%) and CD8 (16.6% vs 28.7%) displayed the same pattern. The CD4/CD8 ratio, on the other hand, was much the same in both groups: 1.7 vs 1.5. CD19 were higher in the BAL fluid (20.1%) than in the peripheral blood (4.8%). In the non-neoplastic group the differences between the BAL fluid and the peripheral blood are of the same sign, but less marked. In conclusion, the BAL fluid subset composition in primary lung neoplasia differs from that in the peripheral blood through a reduction of CD3, CD4 and CD8 and an increase in CD19 compared with the peripheral blood. These modifications are less evident in patients with non-neoplastic lung diseases.

[Prevalence of changes in performance, subjective symptoms and occupational dermatitis before and after carrying out improvements in the surgical block of the Modena Polyclinic]. / Prevalenza di alterazioni delle performances, sintomi soggettivi e dermopatie professionali prima e dopo interventi di bonifica di un blocco operatorio del Policlinico di Modena.

The Preventive Medicine Unit for Personnel in the USL N. 16 of Modena has conducted a study to evaluate the prevalence of subjective symptoms and professional dermatitis among nurses working in a general surgery operating theatre of the Modena "Policlinico" Hospital (36 and 41 employees were studied respectively in 1990 and 1991), before and after the installation of gas evacuators and a modification in the use of detergent and disinfectant substances. The study demonstrates that installation of gas evacuating systems, if not supported by an intervention of air-conditioning plant, does not sufficiently reduce alterations in subjective symptoms. On the other hand, the modifications in the use of detergent and disinfectants has demonstrated a favourable reduction in the prevalence of professional dermatitis (from 43% to 18%; chi2 = 4.35, p = 0.037).