Comparative analysis of the chromosomal positions of rDNA genes in species of the tripunctata radiation of Drosophila.

The location of rDNA on chromosomes has been found to be highly variable in different groups of insect families of various orders. Yet, in other insect families the rDNA position is relatively constant. This contrast so far has received limited attention. We investigated the rDNA position on mitotic chromosomes in 18 species of Drosophila, 16 of which are from the tripunctata radiation, subgenus Drosophila, through fluorescent in situ hybridization (FISH). All species showed fluorescent signals only on the sex chromosomes. On the X chromosome a single fluorescent mark, but with variable locations, was found. On the Y, we observed variation both in location and in number of fluorescent marks (from 1 to 5). This constancy of chromosome location, in contrast to the great variability found in other groups, is consistent with the work carried out in other species of Drosophila. This suggests that the presence of a nucleolus organizer region (NOR) on each sex chromosome is probably an ancestral condition in the genus. Moreover, this difference in the variation of rDNA position among groups points out an interesting evolution question, which deserves further study.

Hyperthyroidism and pulmonary hypertension.

In recent years, many authors have described several cases revealing an association between hyperthyroidism and pulmonary hypertension (PH). This observational study was designed to evaluate the incidence of PH in hyperthyroidism and was set in a department of internal medicine and pulmonary diseases with an out-patients department of endocrinology. Thirty-four patients, 25 women and nine men, with a mean age of 38 +/- 15 SD years participated. Twenty had Graves' disease and 14 had a nodular goitre. The patients were divided into two equally matched groups: those with a recently diagnosed hyperthyroidism, taking no drugs (group 1; n = 17) and those in a euthyroid state taking methimazole (group 2; n= 17). Transthoracic Doppler echocardiography was performed and systolic pulmonary artery pressurements of (PAPs) was determined by the tricuspid regurgitation method using the Bernoulli equation. Measurements of triiodothyronine, tetraiodothyronine, free thyroxine (Ft4), thyroid-stimulating hormone (TSH) and antithyroglobulin and antimicrosomal antibodies were also taken. We found a mild PH in seven patients of group 1 and in none of group 2. The mean +/- SD systolic pulmonaryartery pressurewas 28.88 +/- 6.41 in group 1 and 22.53 +/- 1.84 ingroup 2 (P<0.0001). A correlation was found between the TSH value and PAPs (r = -082;P < 0.001) and Ft4 and PAPs (r = 0 85; P < 0.001) in group 1. These findings indicate the presence of a frequent association between PH and hyperthyroidism. We suggest that hyperthyroidism be included in the differential diagnosis of PH.

Pulmonary function in non-insulin-dependent diabetes mellitus.

BACKGROUND: In type I diabetes mellitus, lung function has been investigated in several clinical studies, but there are few data concerning pulmonary function abnormalities in patients with non-insulin-dependent diabetes mellitus (NIDDM). OBJECTIVES: The aim of this study was to assess the presence of pulmonary function abnormalities in patients with NIDDM and to verify the possible associations between diabetic renal microangiopathy, retinopathy and diabetes control. METHOD AND PATIENTS: Thirty patients with NIDDM were collected and divided into two similar groups: subjects with retinopathy and/or diabetic glomerulopathy (group 1, n = 15) and patients without any complications (group 2, n = 15). 17 were males and 13 females, aged from 45 to 81 years. They had had diabetes for 3-23 years and were studied at the Division of Internal Medicine, with an outpatient service for diabetic patients. All patients were non-smokers. The presence of diabetic glomerulopathy was determined by measuring the 24-hour protein excretion rate using the nephelometric method. The presence of retinopathy was determined by using ophthalmoscopy. Glycosylated hemoglobin was measured as an indicator of glycemic control. We performed a global spirometry and measured pulmonary diffusion capacity by the single-breath method corrected by alveolar volume. RESULTS: We found a significant reduction in lung diffusion capacity for carbon monoxide (DL(CO)) in the group of patients with other signs of diabetic microangiopathy (p < 0.005) and a significative correlation between DL(CO )and the grade of albuminuria (r = -0.83, p < 0.001). CONCLUSIONS: Pulmonary function abnormalities, in particular a reduction in diffusion capacity, are common in patients with NIDDM and signs of diabetic microangiopathy. A possible explanation is related to an impaired pulmonary microvasculature and alveolar epithelial basal lamina.

Changes in the carbon monoxide diffusing capacity of the lung in ulcerative colitis.

The aim of this study was to investigate lung function in patients with ulcerative colitis and to assess the incidence of latent pulmonary involvement in subjects with active and inactive disease. After full colonscopic assessment with multiple mucosal biopsy, the clinical disease activity of each patient was quantified, using the simple index of Harvey and Bradshaw. The patients were divided into 2 equal groups: subjects with active disease (group 1; n=16); and those with inactive disease (group 2; n=16). Global spirometry was then performed. A latent pulmonary involvement was found in 17 of 32 patients (53%), the incidence was higher in the group 1 patients (81%). The majority of patients presented a reduction in the carbon monoxide diffusing capacity of the lungs (DL,CO). The mean DL,CO value was 73.87+/-14.87 in group 1 and 87.31+/-11.23 in group 2. The DL,CO and KCO reduction correlated significantly with intestinal histopathological grading in the group of patients with active disease (r=0.87, p<0.001; r=0.603, p=0.015). To conclude, a high incidence of pulmonary function abnormalities were identified, despite the lack of radiological alterations (High Resolution Computed Tomography) and pulmonary symptoms, in ulcerative colitis patients. These alterations were more common in patients with active disease. The strong correlation between DL,CO values and histopathological grading suggests that this test may reflect bowel disease activity.

[Pulmonary complications in diabetes mellitus]. / Complicanze polmonari in corso di diabete mellito.

The lung is not considered a target organ in diabetes mellitus. In English language literature there are many papers showing the opposite. Many studies demonstrated a thickened alveolar epithelial and pulmonary capillary basal lamina and a reduced lung elasticity, others showed that these histopathological alterations developed into functional abnormalities: reduced lung volumes, reduced pulmonary diffusion capacity and elastic recoil. The pathogenesis is currently thought to involve the nonenzymatic glycosylation (NEG) of tissue proteins inducing an alteration in connective tissue. In patients with diabetic autonomic neuropathy there is an abnormal basal airway tone due to an alteration in vagal pathways: these patients have a reduced bronchial reactivity and bronchodilatation. Diabetic patients have an increased propensity to acquire infections, in particular tuberculosis and pulmonary fungal diseases (coccidioidomycosis, aspergillosis and mucormycosis). The frequency of occurrence of tuberculosis is reported to be four times than in non diabetics, there is a predilection for the lower lobes and the disease is more aggressive in poorly controlled diabetes mellitus. Pulmonary mucormycosis is an infection caused by Phycomycetes, the fungus has the propensity to invade vascular structures giving hemoptysis and leading to a high mortality unless diagnosed promptly. The mechanism for the increased susceptibility to infection is due to an alteration in chemotactic, phagocytic and bactericidal activity of polymorphonuclear leukocytes.