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L Nanni

Publications and source records attributed to L Nanni.

32 records · Page 2Linked to original sources
PubMed1997

p40 molecule regulates NK cell activation mediated by NK receptors for HLA class I antigens and TCR-mediated triggering of T lymphocytes.

p40 was previously described as a regulatory molecule capable of inhibiting both the natural and the CD16-mediated cytotoxicity of NK cells. In this study, we analyze the effect of p40 molecule engagement on the NK cell triggering induced by activating HLA class I-specific NK receptors (NKR) or on TCR alpha beta-mediated T cell activation. CD3-CD16+ NK cell clones expressing activating NKR (either CD94 or p50) were analyzed in a redirected killing assay using P815 target cells and appropriate mAb. A strong target cell lysis was detected in the presence of anti-NKR or anti-CD16 mAb alone. Addition of anti-p40 mAb resulted in a strong inhibition of both anti-NKR or anti-CD16 mAb-induced cytolysis. mAb specific for either CD45 or lymphocyte function associated antigen-1 did not exert any inhibitory effect in the same experimental system. Free intracellular calcium ([Ca2+]i) increase induced by mAb cross-linking of activating CD94 or p50 was inhibited by simultaneous engagement of p40 molecules, but not of other NK surface molecules including CD44 and CD56. In addition, cross-linking of p40 molecules strongly inhibited the CD94-induced tumor necrosis factor-alpha and IFN-gamma production. Analysis of TCR alpha beta or gamma delta T cell clones revealed that the engagement of p40 molecules, using specific mAb, induced some degree of inhibition only on anti-V beta (but not anti-V delta or anti-CD3) mAb-induced cytotoxicity. On the other hand, the p40 molecule engagement prevented T cell proliferation induced by either anti-V beta 8 or anti-V delta 2 mAb. A similar inhibitory effect was found on the IL-2-induced NK cell proliferation. Taken together, our present findings suggest that p40 may play a role in the regulation of NK and T lymphocyte activation and proliferation.

Calcium↗
PubMed1996

A split hand-split foot (SHFM3) gene is located at 10q24-->25.

The split hand-split foot (SHSF) malformation affects the central rays of the upper and lower limbs. It presents either as an isolated defect or in association with other skeletal or non-skeletal abnormalities. An autosomal SHSF locus (SHFM1) was previously mapped to 7q22.1. We report the mapping of a second autosomal SHSF locus to 10q24-->25. A panel of families was tested with 17 marker loci mapped to the 10q24-->25 region. Maximum lod scores of 3.73, 4.33 and 4.33 at a recombination fraction of zero were obtained for the loci D10S198, PAX2 and D10S1239, respectively. An 19 cM critical region could be defined by haplotype analysis and several genes with a potential role in limb morphogenesis are located in this region. Heterogeneity testing indicates the existence of at least one additional autosomal SHSF locus.

Abnormalities, Multiple↗
PubMed1996

Expression of human NKRP1A by CD34+ immature thymocytes: NKRP1A-mediated regulation of proliferation and cytolytic activity.

In this study, we show that NKRP1A is expressed and functions on a subset of immature human thymocytes. We took advantage of the monoclonal antibody (mAb) 191B8 that was obtained by immunizing mice with cultured human thymocytes characterized by an immature surface phenotype [CD2- CD3- CD4- CD8- stem cell factor receptor (SCFR)+] and expressing cytoplasmic CD3 epsilon chain. The 191B8 antibody homogeneously reacted with the immunizing population but not with most unfractionated thymocytes. It stained a minor population of resting immature thymocytes co-expressing CD34, SCFR, or both. Following culture of the CD34+ or CD34- fractions of CD2- CD3- CD4- CD8- purified immature thymocytes with recombinant interleukin-2 (rIL-2), the 191B8-defined antigen was expressed on virtually all cells even when 191B8+ cells were removed from the starting population. On the other hand, no 191B8+ cells were detected in fresh or cultured thymocytes expressing a more mature phenotype. Biochemical analysis of 191B8 mAb-reactive molecules revealed, under non-reducing conditions, two bands displaying apparent molecular masses of 80 and 44 kDa and a single band of 44 kDa under reducing conditions. Digestion with proteases indicated that the 80-kDa form represented a homodimeric form of two 44-kDa molecules, while deglycosylation with N-glycanase suggested the existence of four N-glycosylation sites. Transfection of COS7 or NIH3T3 cells with hNKRP1A cDNA showed that the 191B8 mAb recognized NKRP1A as shown by both immunofluorescence analysis and immunoprecipitation experiments. Functional studies showed that the 191B8/NKRP1A molecule mediated strong inhibition of the cytolytic activity of cultured CD2- CD3- immature thymocytes against a panel of tumor target cells. More importantly, 191B8 mAb induced proliferation of CD2- CD3- fresh thymocytes which was not increased by rIL-2. Thus, we propose that NKRP1A molecules, which are expressed in highly immature thymocytes, may play a regulatory role in their growth and function.

Antigens, CD34↗
PubMed1996

Endoscopic treatment of chronic idiopathic pancreatitis in children.

The purpose of this study was to analyze the preliminary results obtained with endoscopic treatment of children with chronic idiopathic pancreatitis. The disease appears to be caused by a deficit of pancreatic stabilizing proteins that leads to precipitation of solutes contained in the pancreatic secretions; these precipitates are the cause of inflammation. The possible role of a congenital malformation in the pathogenesis of this disease is being regarded with increasing scepticism. Between October 1991 and April 1994, five cases of chronic pancreatitis were referred to the Division of Pediatric Surgery of the Policlinico "A. Gemelli" of Rome. The age range of the patients (3 boys, 2 girls) was 3 to 14 years (mean, 10.8 years); all had a history of acute attacks and had blood chemistry findings compatible with pancreatitis. None of the patients' families had a history of pancreatic disease. All diagnoses were confirmed by endoscopic retrograde cholangiopancreatography, and the disease was staged according to the criteria of Cremer et al. Endoscopic pancreatic sphincterotomy, with or without removal of calculi, was performed in four cases (2 in the authors' hospital, 2 in another institution). Three of the children have had no further symptoms (mean follow-up period, 20 months), and their growth and weight gain have been normal. The fourth child, a 3-year-old girl, has had two episodes of pain since treatment. These attacks, both of which subsided spontaneously, probably were caused by the passage of protein plugs through the sphincterotomy. The fifth patient received no treatment because she had remained asymptomatic since the first examination (28 months ago). The short-term effects observed in these children indicate that endoscopic treatment of chronic idiopathic pancreatitis is associated with a high rate of success with respect to pain control. Because of the short follow-up, the effects on endocrine and exocrine function have not been assessed. No deaths or complications occurred. Conservative treatment of this type can be repeated if pain recurs, an important factor given the chronic nature and early onset of this disease, and it does not preclude the possibility of subsequent surgery. The authors' experience indicates that this approach should be considered the initial treatment of choice for children with chronic pancreatitis.

Child↗
PubMed1995

General role of HLA class I molecules in the protection of target cells from lysis by natural killer cells: evidence that the free heavy chains of class I molecules are not sufficient to mediate the protective effect.

Some HLA-C alleles have been shown to exert a specific protective effect preventing target cells from lysis by groups of natural killer (NK) clones displaying a defined specificity. In this study, we analyzed whether class I-mediated protection is a more general phenomenon involving all NK cells. First, we utilized two anti-class I mAbs (6A4 of IgG1 isotype and A6-136 of IgM isotype), which had been shown to induce lysis of protected target cells by group 1 and group 2 NK clones. Addition of A6-136 or 6A4 used as F(ab')2 mAb resulted in lysis of protected target cells by all NK clones analyzed. Target cells were represented by a panel of HLA homozygous Epstein-Barr virus-transformed B cell lines (B-EBV) while NK clones were representative of clones displaying different GL183/EB6 surface phenotypes and/or different abilities to lyse allogeneic cells. Unselected NK clones derived from seven different individuals were tested against autologous target cells represented by phytohemagglutinin-induced blasts or B-EBV transformed cell lines. In both instances, addition of a mixture of 6A4 F(ab')2 and A6-136 mAbs resulted in lysis of autologous target cells, thus suggesting that class I molecules prevent lysis of normal cells by self NK cells. We further investigated whether the class I-mediated protection requires the complexed form of class I molecules (composed of alpha chain, beta 2-microglobulin and the antigen peptide) or rather the free alpha chain. Acidic treatment of the C1R (Cw4+) target cells or 81.22 (Cw3+, Cw4+) at pH 2.2 resulted in loss of reactivity with 6A4, A6-136 and W6-32 mAb (known to react with the assembled form of class I molecules) and in the de novo reactivity with L31 mAb (specific for the HLA-C free chain). While the untreated Cw+ C1R cells were resistant to lysis by the Cw4-specific group 1 NK clones, the pH 2.2-treated cells became highly susceptible to lysis by the same clones. These data indicate that, at least for the NK clones analyzed, the protection of target cells requires class I molecules in the complexed form.

Alleles↗
PubMed1994

Self class I molecules protect normal cells from lysis mediated by autologous natural killer cells.

The surface expression of given HLA class I alleles protects target cells from lysis mediated by natural killer (NK) clones specific for these (or related) alleles. We could define two groups of NK clones specifically recognizing either Cw4 and related C alleles ("group 1") or Cw3 and related C alleles ("group 2"), respectively. Monoclonal antibodies (mAb) to class I molecules should interfere with the interaction between NK receptors and class I molecules, thus resulting in lysis of protected target cells. However, none of the numerous available mAb to class I molecules had this effect. Therefore, we attempted to select new mAb on the basis of their ability to induce lysis of Cw4- or Cw3-protected lymphoblastoid cell lines by "group 1" or "group 2" NK clones, respectively. From mice immunized with phytohemagglutinin (PHA)-activated lymphocytes expressing either Cw3 or Cw4 alleles, two mAb were selected, the 6A4 (IgG1) and the A6-136 (IgM), on the basis of their ability to induce lysis of protected target cell. Both mAb immunoprecipitated molecules which, in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, gave two bands of 45 and 12 kDa, typical of the class I heavy chain and beta 2 microglobulin, respectively. It has been proposed (but not proven), that self major histocompatibility complex class I molecules protect normal cells from autologous NK cell lysis. Thus, we used the 6A4 and A6-136 mAb to assess this possibility directly. Cw4-specific ("group 1") and Cw3-specific ("group 2") NK clones were isolated from donors expressing the corresponding (or related) protective C alleles. None of these clones lysed autologous PHA-induced blasts, used as target cells. However, addition of the F(ab')2 of 6A4 mAb or the A6-136 mAb resulted in lysis of autologous target cells by "group 1" or "group 2" NK clones, respectively. These data provide direct evidence that the expression of class I molecules protects normal cells from lysis by autologous NK cells.

Animals↗
PubMed1994

Treatment of intraosseous arteriovenous fistulas of the extremities.

Intraosseous arteriovenous fistulas of the extremities are rare malformations frequently associated with severe systemic hemodynamic alterations. In many cases, it is quite difficult to eliminate these anomalous vascular structures, but the possibilities for successful treatment are much greater when surgery is combined with interventional radiology. Selective embolization of the malformed vessels can be produced with a variety of agents that are injected into afferent arteries, via percutaneous puncture or through direct surgical access. The intraosseous portion of the fistula should be resected at the time of embolization or later. The authors describe the successful treatment of three patients having intraosseous arteriovenous fistulas of the upper extremities, who have had follow-up for 2 to 10 years.

Adolescent↗
PubMed1994

Accessory lower limb in a newborn with multiple malformations.

Accessory lower limbs are rare anomalies that are associated with other severe malformations. The authors describe a case of this type and discuss the pathogenetic and classification problems surrounding these malformations in the light of the limited number of the other cases reported in the literature.

Abnormalities, Multiple↗
PubMedDate not supplied

H-type rectovaginal fistula associated with the Currarino triad.

We describe a case of H-type rectovaginal fistula associated with the Currarino triad (anorectal stenosis, sacral defect, presacral mass). Presenting symptoms included passage of feces per vaginam, signs of intestinal subocclusion without perianal inflammation, left leg paresis and foul-smelling urine. An anterior sacral meningocele was repaired at the age of three months. At age 18 months the fistula was excised through a perineal approach after creation of a protective colostomy. Diagnostic and therapeutic aspects of this malformation are discussed.

Abnormalities, Multiple↗
PubMedDate not supplied

Bilateral renal vein thrombosis as a complication of gangrenous appendicitis.

Bilateral renal vein thrombosis after an appendectomy has never been reported in the pediatric literature. We describe the case of a 10-year-old boy who developed this very unusual complication following appendectomy for gangrenous appendicitis with peritonitis. Color duplex Doppler is the most appropriate investigation to allow correct diagnosis and immediate medical treatment. Peritoneal dialysis is a simple and effective tool to prevent permanent damage to renal function.

Appendectomy↗
PubMedDate not supplied

[One-stage "forced" closure of large congenital defects of the abdominal wall with mechanical ventilation and curarization. Clinical evaluation].

Advantages of primary fascial closure of abdominal wall defects are mainly in reducing the number of staged procedures with related complications and the need of multiple operation. Nevertheless correction of large defects still remains a challenge to pediatric surgeon. Postoperative paralysis and mechanical ventilation after intraoperative milking of intestinal content and abdominal muscles stretching have been reported to reduce the risks of "forced" primary closure. A series of 64 Omphalocele and Gastroschisis has been reviewed. Associated anomalies are still the main cause of mortality among Omphalocele. Prematurity plays a secondary role on survival of Gastroschisis cases; deaths were mainly due to sepsis. Primary respiratory insufficiency affected a large number of Giant Omphalocele cases (larger than 5 cm with herniated liver) and was associated to a restricted chest structure. All these cases died in the first weeks of life. Primary closure with or without postoperative paralysis and mechanical ventilation showed to reduce in a significant way the postoperative complication rate compared to staged procedures. Mortality and hospital stay were not significantly influenced by different kinds of surgical treatment among Omphalocele. Associated anomalies are an unavoidable limiting factor to survival. Among Giant Omphalocele the use of aggressive primary fascial closure with ventilatory support showed in our hands to be a safe procedure provided that a preoperative selection of cases on the basis of chest X-ray and blood gases has been made.

Abdominal Muscles↗
PubMedDate not supplied

[A giant lymphangioma of the trunk with a fatal outcome].

The authors describe the case of a 2-month-old male brought to the emergency room in a preagonal state cause by extensive septic necrosis of an enormous lymphangioma located on the left lateral trunk. In spite of emergency treatment the child expired shortly after admission. Our observation of this case prompted a review of the literature on the treatment approaches currently used for these tumors. Emphasis is placed on the necessity for early treatment in order to avoid infectious complications that, if neglected, can lead to unmanageable and possibly fatal sepsis.

Abdominal Neoplasms↗