Immunohistochemical characterization of coronary thrombi in allograft vascular disease

BACKGROUND: Coronary thrombosis is a frequent complication of allograft vascular disease (AVD) in cardiac transplant recipients. No data are available on thrombus composition in these hearts. METHODS: The present study aimed at characterizing thrombus components in coronary arteries from transplanted hearts with AVD, using single and double immunostain with anti-gpIIb-IIIa, anti-fibrin, and anti-endothelial antibodies. The pathologic series consists of 55 grafts survived longer than 2 months, and obtained from 55 patients deceased (n=44) or undergone repeat transplantation (n=11). RESULTS: Mural thrombi were found in multiple segments of 75 of 440 total coronary vessels (17%) (recent in 33, organizing in 28, and organized in 14), whereas occlusive thrombi were found in 19 vessels (8 recent and 11 with multichannel pattern of organization). Recent and thin mural thrombi were mostly constituted of CD41a- and CD61-positive platelets; the amount of fibrin progressively increased with the increase of thrombus size. In organizing mural thrombi, gpIIb-IIIa immunostain was still present. Fibrin was the only identifiable thrombus component in old mural thrombi embedded within the intimal lesions. Recent occlusive thrombi immunoreacted both with anti-CD41a and anti-CD61 and with anti-fibrin antibodies, whereas organized occlusive thrombi with multichannel pattern exclusively immunoreacted with anti-fibrin antibodies. Double immunostain showed that mural thrombi were stratified on de-endothelized arterial segments. CONCLUSIONS: Thrombus composition is related to both type and "age" of thrombus, with platelets as the early and major components of mural microthrombi at one end of the spectrum, and fibrin as the dominant component of occlusive thrombi at the other end.     

Abnormalities of the soleus H-reflex in lumbar spondylolisthesis: a possible early sign of bilateral S1 root dysfunction

Using routine electrodiagnostic procedures, the authors searched for physiologic evidence of nerve root compromise in patients with chronic mechanical perturbation to the lumbar spine. They examined 37 patients with spondylolisthesis and various degrees of degenerative changes in the lumbar canal. Clinical and neurophysiologic findings were compared with data obtained from 36 healthy persons. The soleus H-reflex appeared to be a sensitive indicator of sensory fiber compromise at the S1 root level, because changes correlated well with the focal sensory signs and preceded clinical and electromyographic signs of motor root involvement. When these occurred, the clinical findings were consistent with a more severe nerve root deficit and with radiographic evidence of neural compression. The greater sensitivity of the soleus H-reflex may be related to the pathophysiologic events that occur at the lesion site.     

Immune deficiencies in chronic intestinal pseudo-obstruction

Aim: Chronic intestinal pseudo-obstruction has been associated with urinary disorders, myopathy, and ophthalmoplegia in adults and cholelithiasis in children. We observed a high percentage of total-parenteral-nutrition-dependent patients with pseudo-obstruction and recurrent infections requiring gammaglobulin infusions. Methods: AH records for 23 children with chronic intestinal pseudo-obstruction (10 females and 13 males, mean age 9.8 y ± 4.9 y, range 4–24 y) referred for a nutritional evaluation from 1992 to 1995 were reviewed. Chronic intestinal pseudo-obstruction was diagnosed by clinical, radiographic findings and antroduodenal manometry. Intestinal full-thickness biopsies were performed in seven children. Results: Hypogammaglobulinemia was diagnosed in 18 patients (78%): 16 patients had various immunoglobulin deficiencies and 2 had selective antibody deficiency. Intravenous gammaglobulin was administered in 14 patients. Other medical conditions affecting the children are summarized as follows: autonomic dysfunction in 10 patients (43%), recurrent hypoglycemia in 9 (39%), asthma in 9 (39%), cholecystitis in 7 (30%), low serum carnitine level in 6 (26%), urinary dysfunction in 6 (26%), pancreatitis in 5 (22%), behavioral problems in 5 (22%), myopathy in 2 (9%), idiopathic thrombocytopenia in 2 (8%), velopharyngeal insufficiency in 1 (4%), oculocutaneous albinism in 1 (4%), Pierre-Robin syndrome in 1 (4%), and protein C deficiency in 1 (4%). Munchausen syndrome was suspected in two patients. Conclusions: Chronic intestinal pseudo-obstruction appears to be associated with immune deficiencies. It is unclear if the immune deficiencies, intestinal pseudo-obstruction, and the other medical conditions have a common underlying etiology. Repeated infections may be due to impaired immune function in children with chronic intestinal pseudo-obstruction. We recommend screening for immune deficiencies in children with chronic intestinal pseudo-obstruction.     

Parathyroid hormone is elevated but bone markers and density are normal in young female subjects who consume inadequate dietary calcium

Dietary Ca and osteocalcin (OC), parathyroid hormone (PTH), 25-hydroxyvitamin D (25-OH-D), insulin-like growth factor (IGF)-I and sex hormone binding globulin (SHBG) were assessed simultaneously to bone mineral density (BMD) in 200 adolescent girls (aged 11-15 years) and 100 young women (aged 20-23 years), selected from the lowest and highest end of the Ca intake distribution of a larger population sample. Ca intake was evaluated by food frequency questionnaires, BMD was measured by dual energy x-ray absorptiometry at ultradistal and proximal radius of non-dominant arm, bone age was estimated from x-rays of left hand and wrist according to Tanner et al. (1983). Surprisingly, mean Ca intakes were below the dietary reference intakes in the subgroups of girls and women with the highest measured Ca consumption. Postmenarcheal, but not premenarcheal girls showed radial densities as high as the women and in no group was BMD associated with Ca intake. In all adolescents serum PTH was negatively related to dietary Ca. In girls before menarche IGF-I was positively associated with bone age, while in the same subjects the negative relationship between SHBG and BMD pointed to the crucial role of bioavailable sex steroids on bone mass apposition in early puberty. OC levels decreased progressively with age, while serum 25-OH-D significantly increased after menarche. In conclusion, although in adolescents low Ca intake has not been shown to induce any immediate deleterious effect on radial density, the compensatory hypersecretion of PTH supports the need for an adequate Ca intake to achieve peak bone mass.     

Expression of connexin36 in the adult and developing rat brain

The distribution of connexin36 (Cx36) in the adult rat brain and retina has been analysed at the protein (immunofluorescence) and mRNA (in situ hybridization) level. Cx36 immunoreactivity, consisting primarily of round or elongated puncta, is highly enriched in specific brain regions (inferior olive and the olfactory bulb), in the retina, in the anterior pituitary and in the pineal gland, in agreement with the high levels of Cx36 mRNA in the same regions. A lower density of immunoreactive puncta can be observed in several brain regions, where only scattered subpopulations of cells express Cx36 mRNA. By combining in situ hybridization for Cx36 mRNA with immunohistochemistry for a general neuronal marker (NeuN), we found that neuronal cells are responsible for the expression of Cx36 mRNA in inferior olive, cerebellum, striatum, hippocampus and cerebral cortex. Cx36 mRNA was also demonstrated in parvalbumin-containing GABAergic interneurons of cerebral cortex, striatum, hippocampus and cerebellar cortex. Analysis of developing brain further revealed that Cx36 reaches a peak of expression in the first two weeks of postnatal life, and decreases sharply during the third week. Moreover, in these early stages of postnatal development Cx36 is detectable in neuronal populations that are devoid of Cx36 mRNA at the adult stage. The developmental changes of Cx36 expression suggest a participation of this connexin in the extensive interneuronal coupling which takes place in several regions of the early postnatal brain.     

Torsion of the greater omentum as a rare cause of acute abdomen

Taking as their starting point a case of greater omental torsion recently observed in their surgical department, the authors carefully review the topic and the relevant literature data. This is a rare condition, which though presenting diagnostic difficulties which make it hard to identify preoperatively, poses no problems of a therapeutic nature.     

Surgical treatment of secondary hyperparathyroidism

BACKGROUND: Surgical treatment in the patient effected by secondary hyperparathyroidism consists in subtotal parathyroidectomy or total parathyroidectomy plus autotransplantation of parathyroid tissue. METHODS: The results obtained with surgical treatment of 6 patients observed in the years 1995-1996 are analyzed. Two glands were hyperplastic in four patients, 3 in the others. Every patient was submitted to a subtotal parathyroidectomy. RESULTS: Postoperative course was marked by transient hypoparathyroidism in one case. After 18 months of follow-up, no recurrences were observed. CONCLUSIONS: It is pointed out that in case of secondary hyperparathyroidism subtotal parathyroidectomy represents the surgical treatment of choice, according with literature data. Otherwise total parathyroidectomy plus autotransplantation, characterized by a more complex surgical technique, lead to the same results.