Synchronized onset of nuclear and cell surface modifications in U937 cells during apoptosis.

In this study we investigated the relationship between nuclear and cell surface modifications (i.e. blebbing, phosphatidylserine [PS] and sugar residues exposure) in a monocytic cell line, U937, during apoptosis induced by oxidative stress (1 mM H2O2) or inhibition of protein synthesis (10 microg/ml puromycin). Dying cells were simultaneously observed for nuclear modifications, presence of superficial blebs and plasma membrane alterations. Morphological analysis performed by conventional fluorescence microscopy, or by transmission and scanning electron microscopy showed that the courses of nuclear and membrane alterations occured concomitantly, but the phenotype was dependent on the stage of the apoptotic process and the type of apoptogenic inducer used. The progression of apoptosis in U937 cells beyond early stages resulted in the extensive formation of blebs which concomitantly lost some typical markers of apoptosis, such as PS and sugar residues. Therefore, the modality by which the nucleus condenses, or the amount and the pattern of distribution of PS on the cell surface were, for each cell line, strictly related to the apoptogenic inducer. The morphological data reported in the present paper should lead to a more precise quantification of apoptosis by improving the detection of apoptotic cells in vivo (i.e. in tissue, organs), which is a crucial point in the evaluation of efficiency of antiproliferative drugs, such as antiblastic or immunosuppressive compounds.

Cell shape and organelle modification in apoptotic U937 cells.

U937 cells induced to apoptosis, progressively and dramatically modified their cell shape by intense blebbing formation, leading to the production of apoptotic bodies. The blebs evolved with time; milder forms of blebbing involving only a region or just the cortical part of the cytoplasm were observed within the first hour of incubation with puromycin; blebbing involving the whole cell body with very deep constrictions is the most frequent event observed during late times of incubation. The ultrastructural analysis of apoptotic cells revealed characteristic features of nuclear fragmentation (budding and cleavage mode) and cytoplasmatic modifications. The cytoplasm of blebs does not contain organelles, such as ribosomes or mitochondria. Scarce presence of endoplasmic reticulum can be observed at the site of bleb detachment. However, blebbing is a dispensable event as evaluated by using inhibitor of actin polymerization. In the present study, the progressive modifications of the nucleus, mitochondria, nuclear fragmentation, cytoplasmic blebs formation and production of apoptotic bodies in U937 monocytic cells induced to apoptosis by puromycin (an inhibitor of protein synthesis) were simultaneously analyzed.

Modulation of cell surface expression of liver carbohydrate receptors during in vivo induction of apoptosis with lead nitrate.

Cell surface expression of carbohydrate receptors (i.e. mannose and galactose receptors) and phagocytosis of apoptotic cells by sinusoidal liver cells was studied. Binding sites and phagocytic activity were quantified at different time intervals (1, 3, 5, 7, 9, 11, 13, 15, 20, 30, 40 and 60 days) after the in vivo administration to rats of a potent liver mitogen, lead nitrate, that also induces apoptosis. The number and distribution of binding sites was receptor and cell-type dependent during the days following the metal injection. The use of competing saccharides in inhibition uptake experiments suggests that sinusoidal liver cells actively phagocytose apoptotic hepatocytes and circulating apoptotic cells by using both receptors. In particular, Kupffer cells at 5 and 15 days after the lead nitrate injection are very active in internalizing apoptotic cells (two- to threefold control). However, phagosomes containing apoptotic hepatocytes are often seen inside the cytoplasm of parenchymal and endothelial cells.

[Germ cell tumors in children. Evaluation of regional cases over a 23 year period]. / Tumori a cellule germinali in età pediatrica. Valutazione della casistica regionale osservata nell'arco di 23 anni.

UNLABELLED: A retrospective study on germ cell tumors on children is reported. The purpose of this study was to evaluate some prognostic factors (age, sex, site, histology, treatment) as well as to compare the casistic of Puglia Region with the results of the National literature. 45 patients (30 females, 15 males) aging 2 days-12 years observed in three Pediatric Centres of Bari into 23 years. Primary site of the tumor was: ovary 9, testis 9, sacrococcygeal 16, and others site 11 (head 4, mediastinum 2, pelvis 2, abdomen 2, gluteus 1). HISTOLOGY: teratoma 31, choriocarcinoma 1, embryonal carcinoma 7, endodermal sinus tumor 5, germinoma 1. TREATMENT: surgery 35 patients, surgery+chemotherapy 6, surgery+chemotherapy+radiotherapy 4. Results of treatment: 37 of 41 valuable patients achieved a response (34 complete, 3 partial response); 4 patients had no response. Of the 37 patients that have had a complete or partial remission, 8 subsequently relapsed; of these 8 patients, 5 obtained a second remission after second line therapy, 3 are dead for progressive disease. Better prognosis was observed in children with gonadal tumors treated with surgery alone.

Modifications of electrical potential in corrosive induced lesions of rat oesophagus.

The Authors reproduced, experimentally, lesions of oesophageal mucosa on "Wistar" rats, using 1% and 2% solutions of HCl and NaOH. They studied DP modifications and observed that acid solutions produced a complete and persistent DP modification, while alkaline solutions produce DP inversions that diminish few days after the treatment.

[Emergency surgery for traumatic diaphragmatic hernia. Treatment of 2 cases in children]. / Sull'intervento d'urgenza per ernia diaframmatica traumatica. Trattamento di due casi in bambini

Two cases of tra-matic diaphragmatic hernia, observed in children, are reported. The pathologenesis and therapy are discussed.

[Mediastinal abscess secondary to laceration of the esophagus due to foreign body in a girl (recovery)]. / Ascesso mediastinico secondario a lacerazione dell'esofago da corpo estraneo in una bambina (guarigione)

A case of mediastinal abscess caused by laceration of the oesophagus on removal of a coin swallowed by a young girl is reported. Complete, sequela-free cure was obtained by drainage of the pleural cavity and application of an indwelling nasogastric sound.