Differences in laboratory parameters in clinical categories (CDC/93) of HIV infection

OBJECTIVE: To establish the difference between the evolutive clinical categories (CDC/93) of the HIV infection, on the basis of diverse laboratory parameters. MATERIAL AND METHOD: 332 samples of blood, from 118 patients with HIV infection revised every three months from 1986, were studied. Determinations: haematologic, biochemical and immunologic study. Classification in each review by CDC/93 system. Statistical analysis (R-SIGMA) comparing by ANOVA and NEWMANN-KEULS the averages of the laboratory variables in the clinics categories ("A", "B" and "C"). RESULTS: There are very significant laboratory differences (p < 0.01) between the asymptomatic patients ("A") and the AIDS cases ("C"), with important decrease of hemoglobin, platelets, leukocytes, albumin, CD4+ and CD8+ T cells in the "C" category. On the contrary there is a marked increase of erythrocyte sedimentation, triglycerides, immunoglobulin A and beta 2-microglobulin in those patients with AIDS. CONCLUSION: AIDS patients present very significant differences in ten laboratory parameters, compared to the asymptomatic HIV infected patients. The follow up of these parameters may have prognostic value of AIDS evolution and be useful for the therapeutic decision making.     

A T42A Ran mutation: differential interactions with effectors and regulators, and defect in nuclear protein import

Ran, the small, predominantly nuclear GTPase, has been implicated in the regulation of a variety of cellular processes including cell cycle progression, nuclear-cytoplasmic trafficking of RNA and protein, nuclear structure, and DNA synthesis. It is not known whether Ran functions directly in each process or whether many of its roles may be secondary to a direct role in only one, for example, nuclear protein import. To identify biochemical links between Ran and its functional target(s), we have generated and examined the properties of a putative Ran effector mutation, T42A-Ran. T42A-Ran binds guanine nucleotides as well as wild-type Ran and responds as well as wild-type Ran to GTP or GDP exchange stimulated by the Ran-specific guanine nucleotide exchange factor, RCC1. T42A-Ran.GDP also retains the ability to bind p10/NTF2, a component of the nuclear import pathway. In contrast to wild-type Ran, T42A-Ran.GTP binds very weakly or not detectably to three proposed Ran effectors, Ran-binding protein 1 (RanBP1), Ran-binding protein 2 (RanBP2, a nucleoporin), and karyopherin beta (a component of the nuclear protein import pathway), and is not stimulated to hydrolyze bound GTP by Ran GTPase-activating protein, RanGAP1. Also in contrast to wild-type Ran, T42A-Ran does not stimulate nuclear protein import in a digitonin permeabilized cell assay and also inhibits wild-type Ran function in this system. However, the T42A mutation does not block the docking of karyophilic substrates at the nuclear pore. These properties of T42A-Ran are consistent with its classification as an effector mutant and define the exposed region of Ran containing the mutation as a probable effector loop.     

Disseminated bacillus Calmette-Guerin infection in an HIV-infected child: a case with cutaneous lesions

The present paper addresses mortality from urinary diseases (ICD9 codes 580-599) in the Italian pediatric population aged 0-19 years, in the period 1979-91. Mortality data were obtained from the Italian National Statistical Institute (ISTAT). A total number of 522 deaths were recorded among people aged 0-19 years, amounting to 0.33% of all casualties. Half of these deaths were due to renal failure (ICD9 codes: 584-586). While mortality from all causes decreased by 35% among the Italian pediatric population, mortality from urinary diseases remained stable during the same period, and even increased in the age range 0-4 years (from 3.47 per million person-years in 1979 to 9.83 per million person-years in 1990; p < 0.001). This outbreak in mortality was entirely due to an increase in casualties from acute renal failure (ICD9 code: 584). In conclusion, since the increase in mortality from urinary diseases among Italian children aged 0-4 years takes place in the presence of a substantial drop in mortality from all causes, attention should be paid to this problem and surveillance systems should be reinforced.     

A new bronchoscopic technique for the diagnosis of bacterial pneumonia in HIV-positive patients

The aim of the present study was to evaluate in HIV-positive patients with bacterial pneumonia, the diagnostic value of a new endoscopic technique that uses a single catheter to perform a telescopic plugged catheter (TPC) followed by a modified protected bronchoalveolar lavage (mpBAL). Fifty-eight HIV-positive patients with respiratory infection were included in the study. Samples from TPC and mpBAL were cultured quantitatively. Standard bronchoalveolar lavage was performed to rule out opportunistic infections. According to the clinical and microbiological results, patients were classified in the study group (27 with bacterial pneumonia) or the control group (31 without bacterial pneumonia). Sensitivity of TPC was 56% [95% confidence intervals (CI) 37-75%] and its specificity was 100%; these figures were 56% (CI, 37-75%) and 94% (CI, 86-100%) for mpBAL. When both techniques were assessed together, sensitivity increased to 70% (CI, 53-87%). The use of a single catheter reduced the cost of the originally described pBAL procedure by approximately 50%. The use of a single catheter to perform a TPC followed by a mpBAL can improve the diagnostic yield in HIV-positive patients with bacterial pneumonia, and reduces its cost.     

Exophytic renal angiolipoma versus retroperitoneal liposarcoma

OBJECTIVE: To report a case of exophytic renal angiomyolipoma mimicking a retroperitoneal liposarcoma on magnetic resonance imaging. METHODS: A large, palpable abdominal mass was incidentally discovered during routine physical examination in a 61-year-old, hypertensive woman. A CT scan disclosed a retroperitoneal mass, 17 cm in diameter, adjacent to the kidney. The MRI findings were diagnostic of liposarcoma. The tumor was resected en bloc. RESULTS: The histopathological findings demonstrated angiomyolipoma. CONCLUSIONS: Exophytic angiomyolipoma can mimic retroperitoneal liposarcoma on MRI.     

Primary leiomyosarcoma. A rare tumor of the adrenal gland

OBJECTIVE: To report on a rare case of primary leiomyosarcoma of the adrenal. To our knowledge, this is the fourth case reported in the literature. METHODS: A patient with primary leiomyosarcoma of the adrenal gland is presented. The clinical features are described, and the diagnostic and therapeutic aspects of this rare primary mesenchymal tumor are discussed. RESULTS/CONCLUSIONS: The aggressive nature and the poor prognosis of this rare tumor type are emphasized.     

Mobile thrombus in the right cardiac cavities in patients with severe pulmonary thromboembolism. Importance of echocardiography

The pulmonary thromboembolism is a frequent and severe disease, usually difficult to recognize, specially in patients with thrombotic material trapped within right heart cavities. We present our experience in three patients with severe pulmonary thromboembolism where echocardiographic study demonstrated the presence of huge mobile thrombus in right heart cavities, which demanded urgent therapy with excellent results. We would like to stress that echocardiographic study in these patients could be elective diagnostic procedure, avoiding the realization of pulmonary arteriography, which could bring risk of possible thrombus mobilization.     

Delineation of the epitope recognized by an antibody specific for N-glycolylneuraminic acid-containing gangliosides

P3 is a mouse monoclonal antibody (mAb) that binds to several NeuGc-containing gangliosides. It also reacts with antigens expressed in human breast tumors (Vázquez et al. (1995) Hybridoma , 14, 551-556). In this work, the binding specificity of P3 has been characterized in more detail using a panel of glycolipids that included several disialylated gangliosides and several chemical derivatives of NeuGc-GM3. The carboxyl group and the nitrogen function of sialic acid were found to play important roles in the antibody binding, whereas the glycerol tail appears to be nonrelevant. Molecular modeling was used to analyze the binding data, including the finding that P3 selectively recognizes the internal NeuGc in GD3. For this purpose, conformational studies of GD3 were performed using molecular dynamics. It was concluded that sialic acid binds the P3 antibody through its upper face (the one on which the carboxyl group is exposed) and the C4-C5 side of the sugar ring, whereas none or very little contact between the galactose residue and the protein is evident. Conformational analysis of GD3 revealed that, despite the large flexibility of the NeuGcalpha8NeuGc linkage, the P3 binding epitope on the external sialic acid is not well exposed for any of the possible conformations this linkage can adopt, whereas the internal sialic acid presents the epitope in a proper way for several of these conformations. As a final result, a coherent picture of the epitope that fits the wide binding data was obtained.