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Biomedical subjects

M Solé

Publications and source records attributed to M Solé.

At least 73 records · Page 4Linked to original sources
PubMed1998

Leukocyte infiltration and intercellular adhesion molecule-1-mediated cell interactions in immunoglobulin A nephropathy.

BACKGROUND: Mononuclear leukocytes have a role in immunoglobulin (Ig) A nephropathy. Renal leukocyte recruitment is mediated by adhesive interactions between leukocytes and their ligands on renal cells. METHODS: We assessed interstitial and glomerular leukocytes using an avidin-biotin-peroxidase method with monoclonal antibodies (MAbs) against leukocytes (CD45), beta2-integrin (CD18), macrophages (CD14), T cells (CD3) and T-cell subsets (CD4, CD8), intercellular adhesion molecule-1 (ICAM-1) (CD54), and HLA class II antigens. We analyzed their relation with the abnormal expression of ICAM-1 on proximal tubular epithelium in sequential renal sections from 57 patients with IgA nephropathy stratified by degrees of interstitial cellular infiltration as seen by light microscopy. RESULTS: In IgA nephropathy without infiltration (n = 15) and with interstitial cellular infiltration of 1+ by light microscopy (n = 11), ICAM-1 expression on vascular endothelium was unchanged with respect to that observed in the normal kidney; the proximal tubular epithelium was negative for this stain. Moreover, in IgA nephropathy with interstitial cellular infiltration greater than or equal to 2+ by light microscopy (n = 31), ICAM-1+ stain was seen on proximal tubular epithelium. The value of ICAM-1+ tubule staining was significantly (P = .0004) higher in the biopsies with a higher degree of interstitial cellular infiltration seen by light microscopy. The tubular ICAM-1+ stain was significantly associated with the number of interstitial leukocytes identified by the MAbs tested and correlated (P < .05) with CD45+ (r = 0.59), CD14+ (r = 0.54), and CD3+ (r = 0.51) interstitial leukocytes in IgA nephropathy with interstitial cellular infiltration by light microscopy. Interstitial ICAM-1+ cells and interstitial CD18+ leukocytes were correlated (r = 0.85, P < .001). Correlation was found between the value of ICAM-1+ tubule staining and the number of CD45+ (r = 0.87, P < .01), CD14+ (0.58, P < .05), and CD8+ (r = 0.68, P < .05) glomerular leukocytes. CONCLUSIONS: Our results suggest that tubular and interstitial ICAM-1+ cells may participate in adhesive interactions with interstitial leukocytes. Epithelial tubular cells expressing ICAM-1 may be a marker of tubulointerstitial disturbance upregulated by interstitial and glomerular infiltration of macrophages and T cells in IgA nephropathy.

Cell Communication↗
PubMed1997

Cystic pyeloureteritis: review of 34 cases. Radiologic aspects and differential diagnosis.

OBJECTIVES: To refine the clinical and radiologic description of an unusual benign disease, cystic pyeloureteritis (CPU), consisting of the appearance of suburothelial cysts that raise the mucosa layer of the urothelium. We also studied its relationship with various types of inflammation, including chronic infection, that may be the stimulus for the appearance of CPU. METHODS: We compiled 34 cases of CPU covering the period 1976 to 1994, analyzing the clinical manifestations, diagnostic procedures, differential diagnosis, and evolution. RESULTS: There are no specific symptoms associated with the presence of cysts. The average age of the patients was 59 years (range 30 to 77). Urinary tract infection was detected in 18 (53%). The pyeloureteritis was unilateral in 27 (79%) and bilateral in 7 (21%) of the patients. The location of the cysts was as follows: 1 pyelic (3%); 6 pyeloureteral (18%); and 27 (79%) ureteral. Resolution of the radiologic alterations depends on the resolution of the associated pathology: infections, lithiasis, and obstruction. CONCLUSIONS: We conclude that CPU is a benign pathology with indolent evolution and variable duration; it is not associated with sequelae. Diagnosis is made on the basis of radiologic findings, mainly intravenous urography; in view of the minor entity of the pathology, biopsy is not advisable if the radiologic findings are conclusive.

Adult↗
PubMed1997

Nitric oxide production by peritoneal macrophages of cirrhotic rats: a host response against bacterial peritonitis.

BACKGROUND & AIMS: Patients and rats with cirrhosis and ascites are prone to develop peritonitis. The aim of this study was to assess whether peritoneal macrophages of cirrhotic rats without peritoneal infection produce nitric oxide and express inducible NO synthase (iNOS). METHODS: NO2- accumulation produced by macrophages from control rats and cirrhotic rats with ascites was determined. iNOS messenger RNA and protein expression were analyzed by Northern and Western blot and immunocytochemical analysis. The in vivo effects of inhibiting iNOS were investigated by giving the specific iNOS inhibitor L-N-(1-iminoethyl)-lysine (L-NIL) or sterile saline to 9 and 7 cirrhotic rats with ascites, respectively. RESULTS: Cirrhotic macrophages produced NO2- that was around fourfold greater than that of control macrophages after 30 hours in culture. Northern and Western blot and immunocytochemical analysis showed the presence of iNOS messenger RNA and protein in macrophages of cirrhotic rats. Ascites cultures were positive in all rats administered L-NIL and negative in those administered saline. CONCLUSIONS: Macrophages of cirrhotic rats produce NO and express iNOS messenger RNA and protein, and these changes are not a consequence of overt bacterial infection. Because iNOS inhibition results in peritoneal infection, these results suggest that iNOS induction in macrophages of cirrhotic rats is a host defense response to prevent bacterial peritonitis.

Animals↗
PubMed1997

Intercellular adhesion molecule-1 mediated interactions and leucocyte infiltration in IgA nephropathy.

BACKGROUND: Mononuclear leucocytes have a role in IgA nephropathy (IgAN). Renal leucocyte recruitment is mediated by adhesive interactions between leucocytes and their ligands on renal cells. METHODS: We have assessed interstitial and glomerular leucocytes by avidin-biotin-peroxidase with monoclonal antibodies (MA) against leucocytes (CD45), beta 2-integrin (CD18), monocyte-macrophages (CD14), T (CD3) and T-cell subsets (CD4, CD8), and intercellular adhesion molecule-1 (ICAM-1) (CD54), and analysed their relation with the abnormal expression of ICAM-1 on proximal tubule epithelium in sequential renal sections from 48 patients with IgAN stratified according to the severity of the interstitial cellular infiltration observed by light microscopy. RESULTS: In IgAN without (n = 15) and with (n = 7) interstitial cellular infiltration of 1+, ICAM-1 expression on vascular endothelium was unchanged with respect to that observed in the normal kidney; the proximal tubule epithelium was negative for this stain. In IgAN with interstitial cellular infiltration of 2+ (n = 10), 3+ (n = 11), and 4+ (n = 5), ICAM-1+ stain was observed on the proximal tubule epithelium, the median value of its quantitative expression being 0.3, 0.1, and 0.2 (P = 0.0008), respectively. The tubular ICAM-1 + stain was significantly associated with the interstitial leucocytes identified by MA, and correlated with CD45+ (r = 0.59, P = 0.02), CD14+ (r = 0.54, P < 0.02), and CD3+ (r = 0.51, P = 0.02) interstitial leucocytes in IgAN with interstitial cellular infiltration. Interstitial ICAM-1+ and CD18+ leucocytes were correlated (r = 0.56, P < 0.001). Correlation was found between the quantitative tubular expression of ICAM-1+ and the number of CD45+ (r = 0.98, P < 0.0001), CD3+ (r = 0.48, P = 0.02), and CD8+ (r = 0.76, P < 0.02) glomerular leucocytes. CONCLUSIONS: Our results suggest that tubular and interstitial ICAM-1+ cells may participate in adhesive interactions with interstitial leucocytes. Interstitial T-cells and macrophages as well as glomerular T-cells bearing predominantly CD8+ phenotype could play a role in the induction of the tubular expression of ICAM-1 in IgAN.

CD18 Antigens↗
PubMed1997

Cell-density-dependent expression of Borrelia burgdorferi lipoproteins in vitro.

Previously, we had identified non-OspA-OspB surface proteins of Borrelia burgdorferi that are targeted by the antibody-dependent complement-mediated killing mechanism. Here we demonstrate by Western blotting that one of these proteins, P35, is upregulated at the onset of stationary phase in vitro. Northern analysis revealed that the upregulation of P35 is at the level of transcription. In addition, the expression of an open reading frame (ORF) located downstream of the p35 gene was found to be regulated in the same fashion as that of P35. This ORF encodes a 7.5-kDa lipoprotein. The transcriptional start sites for both of these genes were determined, to aid in the identification of the putative promoter regions. Additional sequencing of the 5' flanking region of the p35 gene revealed a region of dyad symmetry 52 bp upstream of the transcription start site. Southern analysis demonstrated that the expression of these genes was not due to a cell-density-dependent rearrangement in the genome of B. burgdorferi. These findings provide an in vitro model for studying mechanisms of gene regulation in B. burgdorferi.

Amino Acid Sequence↗
PubMed1996

[Usefulness of HLA-DR expression in tubular cells of transplanted kidney for the diagnosis of rejection].

BACKGROUND: Fine needle aspiration is a useful technique as a monitorization method after kidney transplantation for diagnosis of rejection. In addition to the cells of the intrarenal inflammatory infiltrate, the material obtained contains an important quantity of parenchymatous renal cells. The expression of class II HLA antigens in renal tubular cells has been related with episodes of rejection. The aim of this study was to determine the clinical usefulness of fine needle aspiration in diagnosis and control of kidney transplant rejection. PATIENTS AND METHODS: HLA-DR expression of renal tubular cells obtained in 155 fine needle aspirations carried out in 36 consecutive kidney transplantations were prospectively studied. The technique used was that of alkaline phosphatase. The study period included the two months following the graft. RESULTS: Rejection was considered to occur on expression of HLA-DR in more than 20% of tubular cells and as thus this method showed a sensitivity and specificity of 78 and 79%, respectively. Likewise, a good correlation was observed between the persistence of tubular HLA-DR expression following rejection treatment and severity of the same. The group of patients with stable renal function presented a slight, transitory expression within the first 10-12 days after transplantation. CONCLUSIONS: HLA-DR expression of the tubular cells obtained by aspiration puncture is a useful method for the diagnosis and control of kidney transplant rejection.

Graft Rejection↗
PubMed1996

Hereditary hepatic and systemic amyloidosis caused by a new deletion/insertion mutation in the apolipoprotein AI gene.

We report a Spanish family with autosomal-dominant non-neuropathic hereditary amyloidosis with a unique hepatic presentation and death from liver failure, usually by the sixth decade. The disease is caused by a previously unreported deletion/insertion mutation in exon 4 of the apolipoprotein AI (apoAI) gene encoding loss of residues 60-71 of normal mature apoAI and insertion at that position of two new residues, ValThr. Affected individuals are heterozygous for this mutation and have both normal apoAI and variant molecules bearing one extra positive charge, as predicted from the DNA sequence. The amyloid fibrils are composed exclusively of NH2-terminal fragments of the variant, ending mainly at positions corresponding to residues 83 and 92 in the mature wild-type sequence. Amyloid fibrils derived from the other three known amyloidogenic apoAI variants are also composed of similar NH2-terminal fragments. All known amyloidogenic apoAI variants carry one extra positive charge in this region, suggesting that it may be responsible for their enhanced amyloidogenicity. In addition to causing a new phenotype, this is the first deletion mutation to be described in association with hereditary amyloidosis and it significantly extends the value of the apoAI model for investigation of molecular mechanisms of amyloid fibrillogenesis.

Adult↗
PubMed1996

Polymerization of normal and intact beta 2-microglobulin as the amyloidogenic protein in dialysis-amyloidosis.

The primary structure of beta 2-microglobulin (beta 2m), the major constituent protein of beta 2-microglobulin amyloidosis (A beta 2m) or dialysis-amyloidosis, was initially shown to be identical to serum beta 2m, thereby strongly suggesting the polymerization of intact beta 2m in tissues. Recent biochemical data have been controversial, showing beta 2m acidic isoforms, fragmentation and amino acid sequence alteration of deposited beta 2m. The aim of this study was to reinvestigate beta 2m amyloid deposits for the presence of beta 2m fragments and/or amino acid sequence alteration. Four amyloid-laden tissues (3 femoral bone amyloid cysts and 1 heart tissue) from dialysis patients were used to isolate amyloidogenic beta 2m. Amyloid fibrils were isolated using the classic water extraction method, and purified in 6 M guanidine on a gel-filtration column. The protein was further purified on 17% SDS-PAGE gel, and transferred to a nitrocellulose membrane for immunostaining with antihuman beta 2m. beta 2m samples were microsequenced using the standard 03RPTH program on a 470A gas-phase sequencer, and HPLC was performed after digestion with trypsin. Two peaks were obtained with the gel filtration column, the second corresponding by molecular weight to beta 2m. SDS-PAGE analysis of this peak under reducing conditions, demonstrated one major band at 12,000 Da and a minor band at 25,000 Da (monomer and dimer), and no lower molecular weight bands were observed. The 12 kDa band was micro-sequenced and the amino acid sequence corresponded to that of normal beta 2m through the 40th residue. Amino acid sequence analysis showed no difference from normal beta 2m in any of the beta 2m proteins contained in the amyloid deposits isolated from the four studied tissues. Also, the HPLC profile of the four protein samples were strictly normal and identical to a commercial preparation of beta 2m. The present study demonstrates that beta 2m molecules polymerized in amyloid fibrils and deposits are intact and have a normal amino acid sequence, and produced by a specific and unique fibrillogenetic mechanism, which does not require proteolytic processing from the precursor protein to the amyloid fibrils.

Amino Acid Sequence↗
PubMed1996

Hepatocellular carcinoma and cirrhosis. Results of surgical treatment in a European series.

OBJECTIVE: The authors analyze the outcomes of patients with hepatocellular carcinoma (HCC) and cirrhosis who underwent liver resections. BACKGROUND: Liver resection is the best option for HCC arising from hepatic cirrhosis. The experience of Western centers with these patients is shorter than the Asian series. METHODS: Forty-eight consecutive patients with cirrhosis and HCC who underwent liver resections were studied after a similar diagnostic and therapeutic process. Survival and cumulative recurrence were calculated according to pathologic findings. RESULTS: Factors influencing survival at 3 years were as follows: type of resection, absence of vascular invasion, size of the tumor, absence of satellite nodules, and the number of nodules. Factors influencing the rate of recurrence at 3 years were the presence of vascular invasion and the presence of satellite nodules. Patients with favorable prognostic factors have a good survival rate with an acceptable recurrence rate. CONCLUSIONS: Identification of prognostic factors may help in the selection of the appropriate treatment for these patients with HCC and cirrhosis.

Adult↗
PubMed1995

Buffering capacity and H+ membrane conductance of gram-negative bacteria.

Buffering capacity and membrane H+ conductance were examined in seven Gram-negative species: Aquaspirillum serpens, Pseudomonas aeruginosa, Alcaligenes faecalis, Escherichia coli, Salmonella typhimurium, Proteus mirabilis and Aeromonas hydrophila. All strains of Enterobacteriaceae studied here showed a decrease in both parameters as the external pH increased, over the pH range studied. The other four species presented an increase in buffering capacity and membrane conductance to protons as the external pH increased from 5.5 to 7.0.

Buffers↗
PubMed1995

The use of biomarkers for assessing the effects of organic pollution in mussels.

Wild mussels were collected from two stations with different pollution loads. Soft tissues were analyzed for their aromatic hydrocarbon and polychlorinated biphenyl content. Mixed function oxidase (MFO) system components and antioxidant defenses (catalase, superoxide dismutase and glutathione peroxidase) were determined in digestive gland microsomal and cytosolic fractions, respectively, and the magnitude of biochemical responses related with pollutant tissue levels. Results showed that significant differences existed in hydrocarbon content between mussels from the two stations, while a smaller difference in the biological response was detected.

Animals↗
PubMed1995

Bladder wash flow cytometry in transitional cell carcinoma: useful or misleading?

To evaluate the practical usefulness of flow cytometry (FC) applied to bladder wash specimens for the diagnosis of transitional cell carcinoma (TCC), a study was conducted on a series of 101 cases comprising 60 patients with tumor or with past history of TCC, and a control group of 41 patients undergoing cystoscopy for causes other than TCC in which the absence of tumor was confirmed after 1 year of follow-up. When results of the 33 patients with tumor were compared with those of the control group, FC gave low specificity and positive predictive values (54% and 58%, respectively). Conventional cytologic study was superior to FC in this setting. Although the combination of both techniques increased the sensitivity for low-grade tumors, specificity remained lower than that of cytologic study alone. Otherwise, when considering only the cases with a past history of TCC, results of FC were superior to those of cytologic examination, and the combination of both techniques gave high sensitivity and negative predictive values (94% and 93%, respectively). In conclusion, the use of FC in a general diagnostic setting could be misleading, whereas in the follow-up of patients with a history of TCC it becomes a useful adjunct to cytologic study in order to obtain a high diagnostic performance that could allow cystoscopies to be spaced out in these patients.

Carcinoma, Transitional Cell↗