Kidney transplantation from hepatitis B virus core antibody-positive donors: prophylaxis with hepatitis B immunoglobulin.

OBJECTIVE: Hepatitis B virus core antibody (HBcAb)-positive organ donors have the potential to transmit infection to transplant recipients. PATIENTS AND METHODS: We investigated the use of a single dose of 2000 IU of hepatitis B immunoglobulin in 18 patients among a population of 54 kidney transplant recipients from HBcAb-positive deceased donors. RESULTS: Twelve recipients were HBcAb-positive before transplantation. Among the other 42 patients, 5 (11.9%) seroconverted from HBcAb-negative to HBcAb-positive, whereas one HBcAb-positive recipient became hepatitis B virus surface antigen-positive with clinical signs of active hepatitis 6 years after transplantation. In the 18 patients who underwent prophylaxis, we did not find any seroconversion or hepatitis B virus (HBV) transmission. Graft and patient survival of HBcAb-positive kidney transplants did not differ significantly with a matched population of HBcAb-negative transplantation. CONCLUSION: These results suggest that kidney transplantation from HBcAb-positive donors is safe with a low rate of HBV transmission. A prophylaxis with a single shot of hepatitis B immunoglobulin may be effective in reducing the risk of HBV seroconversion or reactivation and may be suggested in all naïve or HBcAb-positive transplant recipients.

Intestinal obstruction by giant Meckel's diverticulum. Case report.

Most cases of Meckel's diverticulum (MD) are asymptomatic and discovered by chance. Management of MD is controversial. The authors describe an exceptional case of intestinal obstruction caused by a giant MD in a patient who had previously undergone appendectomy. A review of the contradictory literature on this subject leads to the conclusion that careful consideration of clinical and morphological data (patient's age, ASA score, the surgical procedure to be performed, morphology and position of the MD, any fibrotic bands) is required before deciding whether or not to resect an asymptomatic MD.

Assessment of cyclin D1 overexpression as a prognostic factor in soft tissue sarcomas: role of laparoscopy and core needle biopsy.

BACKGROUND: This study was designed to test cyclin D1 as a prognostic marker in patients with soft tissue sarcomas (STS), and to evaluate the usefulness of laparoscopy for determining cyclin D1 overexpression. METHODS: The records of 62 patients with STS were collected: 28 with retroperitoneal STS (RSTS) and 34 with extremity STS (ESTS). A total of 51 patients underwent surgical resection, whereas 11 did not undergo surgery because of advanced tumor stage. Preoperative-intraoperative laparoscopic staging was performed for patients judged to be resectable at preoperative imaging. RESULTS: Cyclin D1 was overexpressed in 30 (58.8%) of 51 resected patients and in 10 (90.9%) of 11 nonresected patients. Laparoscopy avoided unnecessary laparotomy in 9 (32.1%) of 28 RSTS patients. CONCLUSIONS: High tumor grade, positive surgical margins, local recurrence, distant metastases, and cyclin D1 overexpression were related to poor survival. Multivariate analysis demonstrated cyclin D1 to be the only independent factor. Laparoscopy was shown to be useful for avoiding useless laparotomies.

Comparison between different methods to assess the prevalence of obesity in a sample of Italian children.

The aim of this study was to compare how different diagnostic criteria can influence the estimation of obesity in children. Five hundred and eighty-seven children from Southern Italy were evaluated for the presence of obesity according to six different methods: two using Ideal Body Weight, according to Tanner and the National Center for Health Statistics, and four using Body Mass Index, according to Rolland-Cachera, Must, Cole (International Obesity Task Force) and the Centers for Disease Control and Prevention. Large discrepancies were found between old and new methods in identifying childhood obesity with respect to absolute prevalence, differences between the sexes, and age-related trends. The use of different weight-height indices, the employment of different cut-off points, the large differences between the reference populations, and the different time periods of data collection explain differences between methods. This should be always taken into consideration when data from different epidemiological or clinical studies are compared.

Histamine plasma levels and elimination diet in chronic idiopathic urticaria.

OBJECTIVE: The aim of this study was to evaluate the effects of an oligoantigenic and histamine-free diet on patients affected with chronic idiopathic urticaria (CIU). DESIGN: Ten patients with chronic idiopathic urticaria were prescribed an oligoantigenic and histamine-free diet for 21 days, followed by serial and controlled reintroduction of foods during a further 70 days. Modification in clinical illness as well as histamine plasma levels, post-heparin plasma diamine oxidase (DAO) and intestinal permeability were evaluated. RESULTS: The oligoantigenic and histamine-free diet induced a significant improvement of symptoms (P<0.05). Moreover, CIU patients on free diet showed higher histamine plasma levels (P<0. 05 vs post-diet and vs controls) that fell to control levels during the oligoantigenic and histamine-free diet. Post-heparin plasma diamine oxidase values were slightly reduced and were unchanged during the diet as well as intestinal permeability, which was always normal in all patients. CONCLUSIONS: These data suggest that histamine plays a major role in chronic idiopathic urticaria. The finding of normal intestinal permeability suggests that a morphological damage of intestinal mucosa should be excluded in these patients. However, the presence of low levels of post-heparin plasma diamine oxidase may indicate a subclinical impairment of small bowel enterocyte function that could induce a higher sensitivity to histamine-rich or histamine-producing food. European Journal of Clinical Nutrition (2000) 54, 155-158

Bone regeneration in the edentulous ridge expansion technique: histologic and ultrastructural study of 20 clinical cases.

The edentulous ridge expansion (ERE) technique is a partial-thickness flap procedure for implant surgery that was developed in 1986. The ERE technique permits the use of osseointegrated implants at sites whose minimal orofacial dimensions are insufficient for traditional implant surgery. The present work is a histologic and ultrastructural study of hard tissue repair modalities at edentulous sites that were treated with the ERE technique in 20 humans. Biopsies were obtained from the tissue regenerating within the surgically created bone gap between the mobile buccal and nonmobile lingual or palatal bone-periosteum plates ("bone flaps") on days 40, 90, 120, 150, and 480 (day 0 = day of implant insertion). The results suggest that osteoblasts differentiate from preexisting mesenchymal cells located on the original fissure walls, with consequent deposition of new bone in the surgically created intrabony defect.

Fractional Talbot imaging of phase gratings with hard x rays.

Fractional Talbot images of optical gratings acting as periodic phase objects have been obtained by use of x rays of 0.069-nm wavelength from a third-generation synchrotron radiation source. Quantitative evaluation of the data obtained as a function of defocusing distance provides information on the lateral coherence of the beam as well as on the phase modulation in the object.

Distinct regulatory roles of lymphocyte costimulatory pathways on T helper type-2 mediated autoimmune disease.

We assessed the role of CD40-CD40L, cytotoxic T lymphocyte (CTL)A4/CD28-B7s, and CD2-CD48/CD58 lymphocyte costimulatory pathways in the development of mercury chloride (HgCl2)-induced autoimmune disease in mice, which is believed to be mediated by T helper (Th) subset Th2. Inhibition of CD40-CD40-L and CTLA4/CD28-B7s interactions by anti-CD40-L antibody and soluble CTLA4-immunoglobulin (Ig) fusion protein, respectively, abrogated the autoimmune disease without affecting interleukin 4 (IL-4) production, showing the importance of physical contact between T and B lymphocytes in the Th2-mediated process. In contrast, two anti-CD2 antibodies that have been shown to induce immunosuppression of Th1-mediated events exacerbated the autoantibody response and augmented IgG1, IgE, and IL-4 production, transforming a mild mesangial glomerulopathy into a severe systemic immune complex disease. These observations demonstrate that manipulation of lymphocyte accessory counterreceptor interactions may affect the course of Th2-associated autoimmune disease and suggest that signals resulting from CD2 engagement play an essential role in the regulation of the Th1-Th2 effector equilibrium.

Early fracture callus in the diaphysis of human long bones. Histologic and ultrastructural study.

The medullary callus and the periosteal callus of fractured long bones were studied in 26 adults undergoing open reduction and internal fixation of closed diaphyseal fractures that occurred 1 to 21 days before surgery. In the 1st week after fracture, a progressive increase was observed in the number of polymorphic mesenchymal cells in the medullary callus and of fibroblast-like cells in the periosteum, where the first calcification foci were seen 7 days after injury. In the 2nd week after fracture, the medullary callus presented numerous mesenchymal cells, fibroblasts, and newly formed capillaries, whereas the inner periosteal layer showed many osteoblast-like cells. New bone trabeculae were first seen in the periosteal callus 12 days after injury. In the 3rd week after fracture, new trabecular bone appeared in the medullary callus. Cartilage also became apparent in the medullary and periosteal callus but remained limited in amount. Calcification within cartilage was first observed in the periosteum 18 days after fracture. The process of fracture healing in long bones in humans is similar, though not identical, to that described for long bones in laboratory animals.

Histology and ultrastructure of arteries, veins, and peripheral nerves during limb lengthening.

The effects of lengthening of the metacarpal bone on peripheral nerves and blood vessels were studied in 8 calves. Specimens for light and electron microscopy were obtained from the palmar neurovascular bundle at 1 cm (8% of the initial length), 2.5 cm (20% of the initial length), and 4 cm (33% of the initial length) of metacarpal lengthening. In 2 calves, specimens were studied 2 months after the end of the lengthening procedure. At 8% of lengthening, myelinated fibers of the palmar nerve showed moderate degenerative changes in the myelin sheath. This became severe at 20% and 33% of lengthening, and affected the axoplasm as well. At 20% of lengthening, the palmar vein started to show fibrous metaplasia of the smooth muscle tissue of the tunica media. This became much thinner than normal. The palmar artery showed moderate alterations of the inner part of the tunica media and the intima. The palmar nerve and blood vessels recovered their normal structure almost completely 2 months after the end of the lengthening procedure. The morphologic alterations of peripheral nerves and vessels may constitute the pathophysiologic basis of the nervous and circulatory disturbance observed in clinical practice.

Localization of ahe alpha 6 and beta 4 integrin subunits in normal human non-lymphoid tissues.

The alpha 6/beta 4 integrin, of undefined receptor activity, has been shown to be expressed in a variety of murine epithelial cells. To gain information on the role of this heterodimer in tissue architecture as well as in malignant transformation we have performed an extensive immunohistochemical analysis of normal human tissues using monoclonal antibodies to alpha 6 and beta 4 subunits. Because alpha 6 is known to associate also with the beta 1 subunit to form a non-promiscuous receptor for laminin, the expression of beta 1 chain was also evaluated. The results of this study have shown that the alpha 6 chain has a wide distribution in tissues, including small vessels and peripheral nerves. alpha 6 colocalizes with beta 4 and beta 1 in most epithelial cells at the basolateral or basal aspect abutting the basement membrane. In a minority of tissues lacking beta 4, the alpha 6 chain is coexpressed with beta 1. These findings demonstrate that the expression of alpha 6/beta 1 laminin receptor and alpha 6/beta 4 heterodimer is phylogenetically conserved, suggesting that they are likely to play an important role in cellular scaffolding through binding to laminin and to still uncharacterized ligand/s present in basement membranes.

A DNA polymerase from the archaeon Sulfolobus solfataricus shows sequence similarity to family B DNA polymerases.

The gene encoding the thermostable DNA polymerase from the archaeon Sulfolobus solfataricus (strain MT 4) was isolated by means of two degenerate oligonucleotide probes. They were designed on the basis of partial enzyme amino acid sequences. The gene was found to encode a 882 residues polypeptide chain with a deduced molecular mass of about 100 kDa. By comparison with other archaeal genes, putative regulatory sites were identified in the gene-flanking regions. By computer-assisted homology search, several sequence similarities among S. solfataricus and family B DNA polymerases were found. In addition, conserved sequence motifs, implicated in the 3'-5' exonuclease activity of E. coli DNA polymerase I and shared by various family A and B DNA polymerases, were also identified. This result suggests that the proofreading domains of all these enzymes are evolutionarily related.

On the mechanism of action of lonidamine: a study on human erythrocyte membrane.

The incubation of human erythrocytes with increasing levels of the antineoplastic drug Lonidamine clearly indicated a dose-dependent effect on the lipid composition of the plasma membranes. A selective transfer of phosphatidylcholine and cholesterol from membrane to incubation medium and the consequent enrichment in phosphatidylethanolamine of the membrane itself was observed. Moreover, the membranes were found to contain increasing levels of the drug which was incorporated at a constant membrane/medium partition ratio. The changes in composition appeared to be consistent with morphological alterations observed by scanning and freeze-fracture electron microscopy demonstrating changes in cell shape, the presence of numerous intracellular vesicles, and a membrane protein rearrangement. The analysis of intact red cells by nuclear magnetic resonance ruled out the possibility that the alterations described above could be due to an ATP depletion. This further confirmed that cell membranes were the primary target of the Lonidamine action, the previously described energy metabolism impairment being a consequence of a selective damage of cellular membranes, probably originating from the incorporation of the drug into the lipid bilayer.

Treatment of malignant pleural effusions with intracavitary Corynebacterium parvum.

Fifty-three cases of metastatic pleural effusion (30 haemorragic and 23 serofibrinous) were treated with 4 mg of Corynebacterium parvum (CP) injected weekly into the pleural cavity after total thoracentesis. Of the 53 effusions, 24 were metastases from lung cancer and 29 from breast cancer. Complete response (CR) was assessed as total resolution of pleural effusion after explorative thoracentesis. The results were as follows: 15 CR after two injections of CP, 30 CR after three, and 5 CR after the fourth administration. Three of 53 cases could not be evaluated because of early death. Of the 30 clearly haemorragic effusions, 25 turned into serofibrinosis after the first intrapleural injection of CP and the other five after the second. These findings indicate that intracavitary CP is the most adequate treatment for the control of neoplastic pleural effusion because it induces a significant clinical improvement with milder side effects with respect to other drugs and/or physical agents commonly used.

Effects of radiofrequency radiation on rabbit kidney: a morphological and immunological study.

The histopathology of the acute and chronic kidney reaction to low-frequency nonionizing electromagnetic radiation was evaluated in New Zealand white rabbits treated with multiple exposure to 27.12-MHz radiofrequencies. At the end of treatment, the animals exhibited focal tubular necrosis and focal and segmental glomerular sclerosis which in a few months evolved into a membranous nephropathy. The latter was characterized by a diffuse, granular localization of rabbit gamma-globulin and complement in most glomeruli and by electron-dense deposits in the subepithelial zone of the glomerular capillary walls, suggesting that these glomerular changes are induced by the localization of antigen-antibody complexes. The data obtained provide strong evidence for the potential nephrotoxicity of radiofrequency radiation and indicate that these nonionizing types of radiation may be capable of eliciting autoimmune phenomena that are likely responsible for the evolution of renal disease in rabbits.

Differential effect of lonidamine on the plasma membrane ultrastructure of normal and leukemic human lymphocytes.

The effect of Lonidamine on the plasma membrane ultrastructure of normal and leukemic human peripheral blood lymphocytes (hPBL) was studied by freeze-fracture electron microscopy. Lonidamine induces remarkable changes in the intramembrane particle distribution on both fracture faces of the plasma membrane as well as of the intracytoplasmic membranes. In particular, a dose-dependent clustering of intramembrane particles was observed in all cell types examined, i.e., normal T and B lymphocytes, T cells from acute lymphoblastic leukemia, and B cells from chronic lymphocytic leukemia, though to a different extent. Normal T lymphocytes appear to be the most sensitive to the action of the drug, while corresponding B cells are much less affected. As regards leukemic cells, in T lymphoblasts the ultrastructural membrane changes are lower than in normal T lymphocytes, whereas leukemic B cells show the same low response to Lonidamine treatment as their normal counterpart. Such a differential effect may be explained by the different membrane molecular organization displayed by normal T and B lymphocytes and by normal and leukemic cells. Moreover, the extent of the ultrastructural modifications at the plasma membrane level, correlates well with literature data on the inhibition of the aerobic glycolysis induced by Lonidamine on the different lymphoid cell types. These findings seem to further confirm that cell membranes are the primary targets of Lonidamine action.

Postnatal development of epididymis and ductus deferens in the rat. A correlation between the ultrastructure of the epithelium and tubule wall, and the fluorescence-microscopic distribution of actin, myosin, fibronectin, and basement membrane.

The postnatal maturation of regions of the epididymis and intragonadal segment of the deferens duct was studied in the rat by light- and transmission electron microscopy. Maturation of the genital duct starts in the distal cauda epididymidis and ductus deferens after one week of life, and one week later, in the more cranial segments of the epididymis. Epithelial principal cells and peritubular contractile cells are structurally mature 35 days after birth. The synchronous changes of these cells indicate that the same factors control their postnatal maturation. The epithelial principal cells obtain an endocytotic apparatus and long stereocilia, whereas peritubular cells acquire contractile features. These changes are associated with a progressive increase in the immunoreaction for smooth muscle actin in both cell types. Smooth muscle myosin is detected in the apical region of the epithelial cells and the peritubular cell cytoplasm by day one of postnatal development. The differentiation of contractile cells in the wall is accompanied by progressive organization of the pericellular matrix into a continuous basement membrane. Although fibronectin is visible at birth, it is gradually removed from the tubule wall.