Biomedical subjects
R Bianchi
Publications and source records attributed to R Bianchi.
[Creatinine and fat cells in the amniotic fluid and their relation to gestational age].
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[A case of acrodermatitis enteropathica].
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[A case of acrodermatitis enteropathica].
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Chemical and biological effects of iodination on human albumin.
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[Anaphylactic shock of humans towards foreign species serum. Symptomatology, prevention and therapy].
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Pulmonary vascular distensibility and lung compliance as modified by dextran infusion and subsequent atropine injection in normal subjects.
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Changes in muscle esterases in genetically dystrophic and control littermate mice.
The hypothesis that the existence of a family of isoenzymes is at the basis of the heterogeneity of esterase activity among skeletal muscles from dystrophic Re 129J and control littermate mice was tested using isoelectrofocusing (IEF) in polyacrylamide gel. All muscles considered showed not only quantitative heterogeneity, as previously observed in this laboratory, but also qualitative differences with regard to their esterase isoenzymes. Differences in the number and the relative amounts of isoenzymatic bands were found between different muscles from both control and dystrophic animals. In most dystrophic muscles a new isoenzymatic band appeared at pH 6.6. Another band, identified at pH 5.12, was more pronounced in dystrophic than in control muscles. The specificity of these observations is indirectly supported by the fact that other tissue, such as heart, liver, and kidney, did not show the quantitative or qualitative abnormality present in the dystrophic skeletal muscles.
A new implemented version of program MIR (MIR II): analysis and identification of mathematical models in enzyme and transport kinetic studies.
The computer program MIR previously described (R. Bianchi, G.M. Hanozet and M. Pilone Simonetta, Comput. Prog. Biomed. 16 (1983) 189) that fits trial rate laws to enzyme and transport steady-state kinetic data by the least-squares method has been enhanced. The new version MIR II is an interactive program and it consists of five major routines and a larger number of smaller program elements to perform the linear (three different functional forms) and non-linear (eleven mathematical models) regression analysis of kinetic data from enzyme and transmembrane transport experiments, also in the presence of inhibitors. Other features of the new program include a set of statistics and tests useful for the model building process, for the development of the mathematical model and for its validation and maintenance. An algorithm for fitting a straight line taking into account errors in both x and y is also provided.
Effect of combined Cyclosporine A and liposome encapsulated dichloromethylene diphosphonate on the organisation of the rat thymus: evidence for a role of macrophages in guiding the post Cyclosporine A thymic reorganisation.
Cyclosporine A (CsA) is a powerful immunosuppressant inducing marked involution of the thymic medulla, and disappearance of interdigitating cells (IDCs) and reducing the number of macrophages (Mphi). Usually, while the thymus of rats receiving a short course of CsA promptly recovers after stopping CsA treatment, long term CsA treatment, like mediastinal irradiation, impairs the normal thymic recovery and is thought to be responsible for the development of autoimmune diseases. In the present study we evaluated the role played by the IDCs and Mphi in the normal recovery of the thymic histology at light and ultrastructural level. Besides CsA administration, we also used liposome-encapsulated dichloro-methylene-diphosphonate (lip-CL2MDP), that induces a total depletion of the Mphi resistant to CsA. After a short (21 days) course of CsA and lip-CL2MDP administration, we did not observe the normal recovery of the thymic parenchyma but only cortical zones consisting of lymphoblasts, epithelial cells and Mphi. The CsA/lip-CL2MDP treatment determining the loss of IDCs and Mphi and consequently the loss of the normal thymic histology seems to simulate in the rats, the long term CsA treatment or the mediastinal irradiation. The results obtained suggest that the loss of IDCs and the depletion of Mphi interfere with the normal thymic recovery. The delay in the recovery of I DCs could be a consequence of the absence of macrophages. These findings would indicate that the IDCs, determining the negative selection of T-lymphocytes, are the main cells responsible for the thymic microenvironment.
Incremental diagnostic value of dobutamine stress echocardiography and dobutamine scintigraphy (technetium 99m-labeled sestamibi single-photon emission computed tomography) for assessment of presence and extent of coronary artery disease.
BACKGROUND: The incremental diagnostic value of dobutamine stress echocardiography (DSE) and 99mTc-labeled sestamibi single-photon emission computed tomography for the evaluation of the presence and extent of coronary artery disease (CAD) was assessed with ordered logistic regression and receiver-operating characteristic curves. METHODS AND RESULTS: Forty-five consecutive patients (33 men and 12 women; 53 +/- 6.8 years) underwent exercise electrocardiography and simultaneous DSE and sestamibi single-photon emission computed tomographic imaging. Coronary angiography was performed in all patients (significant coronary stenosis > 50%). On the basis of the results of exercise electrocardiography, the pretest probability for CAD (Diamond's algorithm) was low (45.6% +/- 12.7%). According to ordered logistic regression analysis, some models were estimated that performed a diagnostic accuracy level for CAD. In particular, we evaluated a clinical model (model 1) determined by the following parameters: sex, age, presence of chest pain, and positivity of electrocardiogram during dobutamine stress test. This model was 64.3% +/- 10.7% accurate for the prediction of CAD. The addition to model 1 of DSE parameters (wall motion stress and rest score index and relative difference) (model 2) yielded a diagnostic accuracy of 81.4% +/- 4.3% (p < 0.045), whereas the addition to model 1 of single-photon emission computed tomographic parameters (the difference between perfusional stress and rest score index) (model 3) improved diagnostic accuracy to 92.3% +/- 5.5% (p < 0.003), a level that appeared significantly higher than that of model 2 (p < 0.016). CONCLUSION: Both noninvasive methods for the detection of CAD showed a good diagnostic accuracy, especially when test-derived parameters were combined with clinical data. Nevertheless, the single-photon emission computed tomographic model showed a higher sensitivity compared with the DSE model.
Cytoplasmic changes in satellite cells of spinal ganglia induced by cisplatin treatment in rats.
The effects of cisplatin (cis-DDP) therapeutic treatment on the cytoplasmic compartment of satellite cells (SC) of rat dorsal root ganglia (DRG) were evaluated. Female Wistar rats were treated once a week with i.p. injection of cis-DDP (2 mg/kg) for 9 weeks. Morpho-quantitative changes of the cytoplasmatic organelles in SC cytoplasm from L4-L6 DRG were determined at the electron microscopic level. The quantitative changes in the lysosomal system components called dense bodies (DB) and in the mithocondria were stereologically evaluated. The data from SC were compared to those from the neurons. The cis-DDP treatment induced a great increase in DB and mithocondria volume of SC. Furthermore, the SC sheath showed an increase of the cytoplasmic lamellar expansions responsible of the physical dissociation of SC sheath from the nerve cell body surface. The comparative analysis from SC and neurons showed that the drug affected primarily the SC, supporting the idea that SC could be the initial target of cis-DDP molecule. The alterations of the anatomical relationships between SC and neurons could modify the cell control on extracellular solutions, altering the functional role barrier attributed to SC. It appears that not only the DRG neurons but also and principally the SC were involved in the peripheral neuropathy mechanisms caused typically from therapeutic cis-DDP administration.
Cyclosporine A-induced kidney alterations are limited by melatonin in rats: an electron microscope study.
The effect of melatonin on experimental prolonged cyclosporine A (CsA) nephrotoxicity was analyzed by electron microscopy and morphometry. Twenty female Wistar rats were divided into groups that received (1) CsA at a therapeutic dose (15 mg/kg/day) sc for 40 days; (2) olive oil, CsA vehicle, as controls; (3) CsA plus melaton (1 mg/kg) ip for the same time; (4) melatonin alone, as additional controls. All controls had normal renal ultrastructure. However, in CsA group, both tubular and glomerular alterations were observed. The authors found apoptotic and necrotic proximal tubules with disrupted brush border, swollen mitochondria, abundant lysosomes; in the glomerulus, amorphous basement membrane, and abnormal mesangial matrix. CsA plus melatonin administration partly prevented these changes. Nevertheless, fibrillar deposits in podocytes and basolateral membrane dilatations in proximal tubules were observed. Histopathological analysis on semithin sections and ultrastructural morphometry were also performed. CsA induced interstitial fibrosis, atrophy, and PAS positive inclusions in the proximal tubules. Moreover, CsA reduced glomerular and mesangial volume but enhanced mesangial matrix volume and basement membrane thickness. After CsA plus melatonin, these parameters were reduced in the proximal tubules and restored in the glomerulus. In conclusion, melatonin attenuated morpho-quantitative alterations induced by CsA in the rat kidney.
Dose-dependent mercuric chloride tubular injury in rat kidney.
Mercuric chloride (HgCl(2)) produces an acute renal failure in experimental animal models. Since the mechanism of tubular injury has not completely been clarified, this morpho-quantitative study was undertaken to better understand the effects of 2 sublethal doses (T1=1 mg/kg and T3.5=3.5 mg/kg) of HgCl(2) in rat proximal tubules. Morphometrical analysis was performed to quantify both cytoplasmic and nuclear changes found in treated in respect to saline-injected proximal tubules. In the controls, single-cell damage was occasional and nucleolar changes were absent. HgCl(2) induced progressively severe proximal tubule atrophy. In the T1 group, necrosis was limited to pars recta cells and nucleolar segregation was often partial. In the T3.5 group, atrophy was extensive in both convoluted and straight tracts, the nucleolus was completely segregated and coiled body-like inclusions were detached from it. Ultrastructural analysis confirmed dose-dependent changes within straight proximal tubules, i.e., necrosis, apoptosis, nucleolar segregation, swollen mitochondria, vacuolization, and disrupted brush border. In conclusion, in the rat kidney HgCl(2) induced dose-dependent alterations not only in the cytoplasm but also in the nucleus of proximal tubule cells. These findings will be useful for better understanding of the pathogenesis of mercury nephrotoxicity and its genotoxic effect.
Relationship between renal function and blood level of chromogranin A.
Chromogranin A (CGA) is a low MW (49,000) acidic hydrophilic protein. It is synthesized in the chromaffm granules of the neuroendocrine cells, and has been found circulating in the blood of healthy subjects. The aim of this study was to assess the relationship between serum levels of CGA and renal function. One hundred two renal patients (45 M and 57 F; age 14-76 years, mean 52) participated in the study. Glomerular filtration rate (GFR) was measured by the bladder cumulative method, using 99mTc-DTPA as a tracer. Blood CGA was determined by RIA. Plasma creatinine, beta2microglobulin (beta2m) and tumor associated trypsin inhibitor (TATI) were also determined. The reduction in renal function was associated with an increase in all of the above studied parameters. In patients with advanced renal failure (GFR <20 mL/min) CGA levels increased by 22-fold as compared to the patients with normal renal function (GFR> 100 mL/min). The other studied parameters were also increased but to a lesser degree, e.g., TATI 14-, beta2m 8- and creatinine 5-fold. The results of this study demonstrate that renal handling of the CGA is similar to other low MW proteins, and it accumulates in the blood in renal failure.
Detection of melanoma cells in peripheral blood and sentinel lymph nodes by RT-PCR analysis: a comparative study with immunohistochemistry.
The presence of lymph node metastases is the best prognostic factor for predicting relapse or survival in melanoma patients. It has been demonstrated that melanoma metastases spread through the first lymph node(s) draining the tumor (sentinel lymph node, SN) to the lymphatic system and that detection of melanoma cells in peripheral blood directly correlates with prognosis in melanoma. To identify lymph node metastases and circulating melanocytes, we developed a single-step reverse transcriptase-polymerase chain reaction assay (RT-PCR) for detection of two melanoma-specific markers: the tyrosinase gene, which encodes an enzyme associated with melanin synthesis, and melanoma antigen-related T-cells, which are present in tumor infiltrating T-lymphocytes. This method detects two tumor cells in a background of 10(7) lymphocytes. Thirty patients with stage I-IV cutaneous melanoma entered the study. Blood samples were taken preoperatively, one month after excision of the primary melanoma lesion and the SN or total lymphadenectomy, and before the start of chemotherapy and every three months thereafter in metastatic patients. SNs were collected from 22 patients, bisected and analyzed by RT-PCR and routine pathological and immunohistochemical tests. The preliminary results indicate that RT-PCR for melanoma markers is a sensitive and valuable method for the detection of micrometastases and for early diagnosis and staging of melanoma.
Gamma probe-guided thoracoscopic surgery of small pulmonary nodules.
Video-assisted thoracic surgery (VATS) is an interesting and emerging procedure for the diagnosis and treatment of peripheral pulmonary nodules. We developed a new radioguided surgical technique for the detection during VATS of pulmonary nodules smaller than 2 cm, situated deep in the lung parenchyma and neither visible nor palpable with endoscopic instruments. The procedure is divided into two phases. Two hours before surgery 0.3 ml of a solution composed of 0.2 mL of 99mTc-labeled human serum albumin microspheres (5-10 MBq) and 0.1 mL of non-ionic contrast is injected into the lesion under CT guidance. Then the patient is submitted to VATS. During thoracoscopy a collimated probe of 11 mm diameter connected to a gamma ray detector is introduced via an 11.5 mm trocar and the pleural surface of the suspected area is scanned. A hot spot indicates the presence of the radiolabeled nodule and hence the area to be resected. We treated 39 patients with small pulmonary nodules (mean size, 8.3 mm; range, 4-19 mm). The patients were 27 men and 12 women (mean age, 60.8 years; range, 13-80 years). Nineteen patients had a history of synchronous or metachronous malignancy. In all cases the nodule was detected and resected and the resection margins were pathologically free of tumor. Histological examination showed 21 benign and 18 malignant lesions (7 metastases and 11 primary lung cancers). Nine patients with a frozen section-based histopathological diagnosis of lung cancer without functional contraindications underwent a completion lobectomy by open surgery in the same surgical session. In conclusion, the radiolocalization of small pulmonary nodules by gamma probe during VATS is a safe and easy procedure, with fewer complications and a lower failure rate than other localization techniques.
Ultrastructural study of the alterations in spinal ganglion cells of rats chronically fed on ethanol.
A study was conducted to find the effects of chronic alcohol (EtOh) administration on the rat dorsal root ganglion (DRG) cells in vivo. Morphoquantitative changes of the cytoplasmic organelles in neurons and satellite cells (SC) of lumbar DRG of animals fed with 20 and 40% of EtOH for 6 months were determined at the electron microscopic level. Stereological methods were used to quantitatively evaluate the changes in the neuronal Golgi fields, in the lysosomal system components called dense bodies (DB), in the mitochondria, and in the cytoplasmic perikaryal projections (PP) characteristic of DRG neurons. Prolonged consumption of 20% EtOh was well tolerated by neurons. There were, however, some structural modifications in the studied organelles, and there was a significant increase in the neuronal surface. In SC the number of mitochondria and DB increased significantly. Treatment with 40% EtOH produced massive organelle alterations in both neurons and SC, including disruption of the PP, markedly reducing the neuronal surface area. The architecture of the SC sheath appeared disorganized. The alterations resembled those of senescence, and indicated that a high dose of EtOH (or its metabolites) had a profound disruptive effect on the organelles and on the membrane systems of the DRG cells. The SC of the DRG units from the animals fed with EtOH were the first to show significant morphological alterations. When the architecture of the SC sheath already showed evident signs of disorganization, the neuronal body was just beginning to show morphological damage. These results suggest that the progressive disorganization of the SC sheath is a probable source of complication in peripheral neuropathy.