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.

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.

Lonidamine, a selective inhibitor of aerobic glycolysis of murine tumor cells.

The action of Lonidamine [1-(2,4-chlorobenzyl)-1H-indazol-3-carboxylic acid] on respiration and aerobic lactate production of several murine tumor cells and normal differentiated murine cells was investigated. Lonidamine reduced the oxygen consumption in both normal and neoplastic cells. In contrast, it increased the aerobic glycolysis of normal cells but inhibited that of tumor cells. This selective action might be ascribed to the inhibition of mitochondrially bound hexokinase, which is usually absent in normal differentiated cells.

Effect of lonidamine on the energy metabolism of Ehrlich ascites tumor cells.

The action of Lonidamine [1-(2,4-dichlorobenzyl)-1-H-indazol-3-carboxylic acid] on oxygen consumption and the rate of aerobic and anaerobic lactate production by Ehrlich ascites tumor cells has been investigated. The rate of oxygen consumption decreases exponentially with the increase of Lonidamine concentration, with maximal inhibition occurring at 0.40 mM Lonidamine. The rate of aerobic lactate production is inhibited to the same extent as is the oxygen consumption. However, the maximum effect is observed at 0.12 mM Lonidamine, and the decrease is linear with Lonidamine concentration. Anaerobic lactate production is more sensitive to Lonidamine, and complete inhibition can be observed by raising the concentration to 0.6 mM. The possibility that the decrease observed in lactate production was secondary to the inhibition of sodium- and potassium-containing adenosinetriphosphatase was excluded, because the drug has no effect on this enzyme. Mitochondrial adenosinetriphosphatase was not affected. Lonidamine was, however, shown to inhibit the activity of mitochondrially bound hexokinase to approximately the same extent as it inhibited aerobic glycolysis (approximately 70%). It is concluded that inhibition of the glycolysis of Ehrlich ascites tumor cells by Lonidamine results from an effect of the drug on the mitochondrially bound hexokinase.

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.

Expression of Ia-like antigens in normal human nonlymphoid tissues.

Recent results have demonstrated that Ia-like antigen expression in animal tissues is not restricted to cells associated with immune functions. Whether this phenomenon occurs in normal human tissues has been investigated in this study by indirect immunofluorescence on cryostat sections using monoclonal antibodies to framework determinants of Ia-like antigens. The results of this study show that Ia-like antigens are expressed on several normal human tissues of different embryonic origin. These include the epithelium of the gastrointestinal tract, urinary bladder, bronchial glands, thymic reticuloepithelial cells (entodermic origin), epithelium of mammary gland, acinar cells of parotid, astrocytes (ectodermic origin), alveolar macrophages, Kupffer cells, glomerular and peritubular renal endothelium, endometrium, and Langerhans cells (mesodermic origin).

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

Morphological, immunochemical, and biochemical study of rabbit achilles tendon at various ages.

UNLABELLED: With aging, rabbit tendon tissue undergoes a series of morphological and biochemical changes which involve both the cells and the extrace-lular matrix. The extracellular matrix increases in volume, causing a relative decrease of the number of cells per unit of tissue surface. The tenoblasts become longer and more slender, while their cytoplasmic processes increase in number and become thinner and more elongated, forming a dense network. In addition, tendon cells show a marked decrease in the intracytoplasmic organelles responsible for protein synthesis, while their intracellular content of contractile proteins does not change. With aging collagen fibers increase in diameter and vary more in thickness. These morphological changes correspond to biochemical changes that include an increase in collagen, a decrease in mucopolysaccharides, and a decrease in water content. During aging parallel changes occur in the elastic fibers, which decrease in number and show structural alterations. CLINICAL RELEVANCE: Ultrastructural and biochemical studies of tendon diseases need a normal comparison. Out ultrastructural and biochemical findings in aging tendon may be useful in that regard. The presence of actin and myosin in tendon cells could be related to some aspects of tendon physiology and pathology.

Morphological and karyological studies on in vitro Sertoli cells of adult crab-eating macaques (Macaca fascicularis).

Sertoli cell cultures were obtained from isolated seminiferous tubules of adult crab-eating macaques (Macaca fascicularis). Cells were identified by their morphological characteristics and their capacity to produce and release in the culture medium 17ß-estradiol and androgen-binding protein (ABP). Several cells were undergoing mitosis. Karyological analysis showed both diploid and tetraploid metaphases. Patterns of nuclear scission were also observed.

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.

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.

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.

Regeneration of rabbit calcaneal tendon maturation of collagen and elastic fibers following partial tenotomy.

Regenerated tendon tissue replacing partial-thickness defects produced in rabbit calcaneal tendons was seen to undergo almost complete maturation between three and sixteen weeks after surgery. At this stage, most collagen fibers had large diameters as in normal tendon, and the majority of elastic fibers were mature. This findings, along with those of a previous study on completely severed and unsutured tendons, indicate that mechanical stress plays a primary role in maturation of regenerating tendon. This emphasizes the importance of close approximation of tendon ends in the management of tendon ruptures and lacerations. This is possibly by surgical repair.

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.

Intracellular collagen fibres in regenerating tendon.

Intracytoplasmic collagen fibres contained in elongated membrane-bound structures were observed in fibroblasts of regenerating tendon in the later stages of the repair process. The observations appear to support the hypothesis that collagen fibres of the intercellular matrix may be phagocytosed by the cells and degraded in the intracellular environment. Phagocytosis of extracellular collagen fibres probably represents an additional mechanism of collagen resorption during the later stages of remodelling of the regenerating tendon.

Changes of seminiferous epithelium in hybrids of mice carrying Robertsonian karyotype.

Different wild mouse populations have been found in Italy characterized by different Robertsonian karyotypes. Hybrids between carriers of karyotype have severe impairment of fertility due to different Robertsonian rearrangements, because of the difficulties of the meiotic chromosome pairing. Homozygous Robertsonian mice (Cittaducale, CD, Ancarano, ACR and Lipari Island, LIP) are able to release mature spermatozoa while in hybrid F1 mice (CD X ACR, ACR X LIP, and LIP X CD) the impairment of seminiferous epithelium cycle is evidenced by a germinal aplasia. In the hybrid mice the more predominant lesion is represented by a pathological arrangement of the basement membrane introflecting and splitting inside the seminiferous epithelium.

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.