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M Nigro

Publications and source records attributed to M Nigro.

At least 37 records · Page 2Linked to original sources
PubMed1997

Ultrastructure of the cyst wall of Sarcocystis sp. in roe deer.

Samples of heart, tongue, oesophagus and diaphragm muscle from twenty-two naturally infected roe deer (Capreolus capreolus) harvested in central Italy were examined for sarcosporidiasis. The structure of Sarcocystis spp. muscle cysts was examined by light and electron microscopy. Only one type of thin-walled cyst was distinguished by light microscopy. Electron microscopy showed cysts having a thin highly folded primary cyst wall, without fibrillar material, that formed thin hair-like protrusions often having a T-form, especially close to host cell mithocondria. The cysts appeared to belong to a single Sarcocystis sp. so that all the animals had monospecific infections. This cyst was compared with cysts described in other cervid in an attempt to determine if single or multiple species of the genus Sarcocystis occur in the Cervidae. Apparently, a single Sarcocystis sp. with a low specificity for the intermediate host can infect the Cervidae.

Animals↗
PubMed1996

Physiological studies of spinal inhibitory pathways in patients with hereditary hyperekplexia.

Because hereditary hyperekplexia results from a defect in the glycine receptor, we studied in five patients several spinal inhibitory pathways that are thought to use either glycine or gamma-aminobutyric acid as a neurotransmitter. Three patients had a mutation in the alpha1 subunit of the glycine receptor, whereas two sisters with the same clinical syndrome did not have this mutation. Compared with normal subjects, reciprocal inhibition between flexor and extensor muscles of the forearm was diminished during the first period of inhibition and preserved during the second period of inhibition in all three patients tested. Facilitation after the early period of inhibition was prominent. Recurrent inhibition of the soleus H reflex was normal in four patients, as was inhibition of the H reflex produced by Achilles' tendon vibration. There was no significant difference in nonreciprocal (Ib) inhibition between patients and normal individuals, The findings suggest that disynaptic reciprocal inhibition in humans is mediated through glycinergic interneurons, but that recurrent inhibition may have a contribution from nonglycinergic mechanisms.

Adult↗
PubMed1995

Behavioural development and Doppler velocimetry in relation to perinatal outcome in small for dates fetuses.

Twenty-two small for dates (SFD) fetuses and 96 fetuses from uncomplicated pregnancies were monitored on two occasions between 27 and 32 weeks and the second time between 33 and 36 weeks of gestation by studying the development of behavioural states (coincidence 1F and 2F; no coincidence) and umbilical artery Doppler waveform patterns (UA; Resistance Index, RI). Data were related to neurological outcome at 8 months after birth. The purpose of this study was to investigate if the development of behavioural state is disturbed in SFD fetuses and if SFD fetuses who needed to be delivered early and/or had abnormal neurological outcome showed different state development and RI than SFD fetuses delivered later in pregnancy or with normal neurological outcome. Finally, we studied if there was a relationship between state development and RI. At 27-32 weeks of gestation the percentage of coincidence 2F (C2F%) was lower and the percentage of coincidence 1F (C1F%) and no coincidence (NOC%) were higher in the SFD fetuses than in the control group. At 33-36 weeks C2F% was lower and NOC% was higher but not statistically different (P = 0.2 and P = 0.07, respectively). SFD fetuses who needed to be delivered early had poorer state development than SFD fetuses at lower risk and infants who were abnormal at 8 months of life showed a higher C1F% and lower C2F% at 27-32 weeks. There were significant correlations between RI on the one hand and NOC% (r = 0.62) and C2F% (r = -0.48) on the other hand at 27-32 weeks in the subgroup with abnormal neurological outcome. In conclusion, in SFD fetuses there are disturbances in the development of behavioural states as well in the distribution of the periods of coincidence (with a decrease in C2F% and an increase in C1F%). Poorest state development is present in SFD fetuses at highest risk and in this group there appears to be a significant relationship between the degree of utero-placental insufficiency (RI) and disturbances in behavioural development.

Behavior↗
PubMed1995

Deferoxamine followed by cyclophosphamide, etoposide, carboplatin, thiotepa, induction regimen in advanced neuroblastoma: preliminary results. Italian Neuroblastoma Cooperative Group.

Based upon phase I and II studies of deferoxamine alone and in combination with cytotoxic agents cyclophosphamide, etoposide, carboplatin, and thiotepa (D-CECaT), we initiated a single arm multicentre trial in 1992 for advanced neuroblastoma. 57 of 65 patients who entered the trial were evaluable. Following 4 courses of the D-CECaT, almost all the patients underwent surgery. Toxicity was moderate and mainly reversible myelosuppression. The post-surgically defined responses in stage 3 high risk, stage 4 moderate risk and stage 4 high risk patients included 24 complete responses, 26 partial responses, and 3 minor responses, and 4 patients had progressive disease. These patients are being followed to determine the impact of this programme on their overall survival.

Adolescent↗
PubMed1995

[Renovascular hypertension-bilateral kidney: autotransplantation and reconstruction of the aorta with autologous saphena].

The authors describe a patient with stenosis of the renal artery undergoing bilateral kidney autotransplantation and reconstruction of the aorta with autologous saphena. This study also provides a general evaluation of renovascular hypertension incidence, etiopathogenesis, symptomatology, diagnostic criteria, therapy. The presence of a diastolic pressure > 110 mmHg, with normal creatinin levels and urinalysis results, is very significant and leads to invasive investigations. Site and size of the anatomic anomaly are evaluated by arteriography. Surgery is the treatment of choice.

Angiography↗
PubMed1995

Place of meta-[131I]iodobenzylguanidine in the treatment of neuroblastoma: the Genoa experience.

The aim of this paper is to focus on our previous experience with the treatment of Group 3 and 4 neuroblastoma patients and on the therapeutic use of [131I]MIBG, to better define the role of this radioactive drug in the treatment of neuroblastoma (NB). Analysis of the studies on Group 3 patients treated with chemotherapy and surgery showed that the progression-free survival (PFS) increased from 45% for patients treated before 1985 to 63% for patients treated in the period of 1985-1989 and to 78% for patients treated after 1989. [131I]MIBG administered in 17 Group 3 patients who did not achieve a radical excision of the primary resulted in 7 partial response (PR) and 5 minor response (MR), with 10 cases of long term survival. Results in Group 4 patients confirmed the good prognosis in the subset of children aged 6-12 months at diagnosis (PFS 86% at 5 years). In patients aged > 12 months at diagnosis intensive induction chemotherapy induced a higher response rate of 69% and PFS was 26% at 5 years. [131I]MIBG administered in advanced stage 4 patients induced a response in 50% of the cases (2 complete response [CR], 13 PR and 2 MR out of 34 children) and 8 children treated for residual primary (4 cases) or residual bone metastases (4 cases) are long term survivors. We conclude that [131I]MIBG is the treatment of choice in Group 3 patient with a residual primary tumor and could contribute to consolidate the response obtained in Group 4 patients.

3-Iodobenzylguanidine↗
PubMed1994

Analysis of peripheral blood normal and malignant cells with the novel murine monoclonal antibody UN2.

The monoclonal antibody (mAb) UN2 was generated upon immunization of a Balb/c mouse with human thymocytes. mAb UN2 recognized an antigen expressed by a subpopulation of human thymocytes and peripheral blood lymphocytes. In thymus, mAb UN2 recognized cortical cells; its expression was higher on CD3bright than on CD3dim thymocytes. This antigen was also detected on peripheral blood granulocytes, monocytes, platelets and on cell lines MOLT4, U937 and KG1. mAb UN2 was submitted to the 5th International Workshop and Conference on Human Leukocyte Differentiation Antigens, Boston, MA, 1993, and was assigned to the CD31. Expression of the UN2-recognized antigen in malignant lymphoid cells from 57 cases of B-cell chronic lymphoproliferative disease and 4 of B-cell acute lymphoblastic leukemia was analysed in flow cytometry. Among the 57 cases of B-cell chronic lymphoproliferative malignancies studied, 49 were classified as B-cell chronic lymphocytic leukemia. These showed high (86 +/- 8%) UN2 antigen expression. In 8 cases of hairy-cell leukemia the percentage of cells reacting with mAb UN2 was 42 +/- 4%; the fluorescence intensity of labelled cells was lower than that displayed by cells of B-cell chronic lymphocytic leukemia and comparable to that of normal lymphoid cells. mAb UN2 could prove useful in analysis of the lymphoid development and diagnostics of B-cell chronic lymphoproliferative disorders.

Animals↗
PubMed1994

T cell growth-promoting activity of interferon-gamma. Mitogenic effect of the recombinant cytokine on cells from a human T-chronic lymphocytic leukemia.

Interferon-gamma (IFN-gamma) has previously been described as exerting a growth factor activity for murine and human stimulated normal T lymphocytes, in addition to its established role in regulating the cytotoxic activity of T and NK cells. We analyzed the effect of human recombinant IFN-gamma on the proliferation of leukemic lymphocytes isolated from the peripheral blood of a patient affected by a T-cell chronic lymphocytic leukemia (T-CLL). Incubation with IFN-gamma induced the proliferation of unstimulated leukemic cells. Cell proliferation was maximal after 6 days of culture with the cytokine; the half-maximal effect of IFN-gamma was observed at a concentration of approximately 800 U/ml. We also measured the production of IFN-gamma by leukemic cells. Cells incubated in control medium released small quantities of IFN-gamma activity, while the addition of low doses of the exogenous cytokine to the cell cultures induced high levels of IFN-gamma mRNA and protein production. Furthermore, anti-HLA class I monoclonal antibodies, that exert a mitogenic effect on these neoplastic lymphocytes, also induced the IFN-gamma gene expression in the same cells. These results indicate that IFN-gamma may stimulate the proliferation of human neoplastic T cells and suggest that this cytokine might have a role in the expansion of T-leukemic cell clones in vivo.

Antibodies, Monoclonal↗
PubMed1993

[Echographic assessment of cutaneous neoplasms].

A hundred and fifteen skin tumors were evaluated by means of US. Three variables were considered for each lesion--i.e., borders, echostructure and thickness--and the results compared with histology. High agreement was observed in melanomas: in these tumors, indeed, thickness is well known to be relevant for both surgical planning and prognosis. US scans with a 10 MHz transducer allowed the accurate assessment of borders and structure only in certain, mainly benign, kinds of skin tumors--e.g., angiomas, pilomatrixomas, sebaceous cysts and lipomas--, but also in lymphomas. On the contrary, most malignant neoplasms exhibit hypoechoic structure and borders from clear-cut to blurred. Finally, US proved to be highly reliable in demonstrating lesion thickness before surgery. High agreement was once again observed with histology relative to this variable: thickness (in mm) was the same in 30% of cases, overestimated by US (mean: 0.3 mm) in 44% of cases and underestimated by US (mean: 0.15 mm) in 26% of cases. Particularly, in 41 melanomas, histology-US agreement rate was 44% for the Breslow index, with r = 0.95 and 88% for the Clark index.

Humans↗
PubMed1992

Physiological abnormalities in hereditary hyperekplexia.

Five patients from a kindred with hereditary hyperekplexia had physiological testing. The surface-recorded electromyographic pattern of audiogenic muscle jerks was identical to that of the normal acoustic startle reflex. Testing at graded stimulus intensities indicated an increase in the gain of the acoustic startle reflex. Nose-tap stimuli resulted in short-latency generalized electromyographic bursts that were similar to the R1 component of the blink reflex. Electrical stimulation of peripheral nerves elicited a pattern of generalized muscle jerks that was similar to that of the acoustic startle reflex. Somatosensory evoked potentials, brainstem auditory evoked potentials, and cortical auditory evoked potentials were normal. The primary physiological abnormality in hereditary hyperekplexia is widespread elevated gain of vestigial withdrawal reflexes in the brainstem and possibly the spinal cord, most likely resulting from increased excitability of reticular neurons.

Acoustic Stimulation↗
PubMed1991

Renal involvement in canine leishmaniasis. A light-microscopic, immunohistochemical and electron-microscopic study.

In a prospective survey in the Isle of Elba, 413 dogs affected by naturally acquired Leishmania infantum infection were identified out of a controlled population of 1,500 resident mongrel dogs. In all the 34 randomly selected dogs of different breed, age, and duration of disease, the presence of glomerular lesions which defined mainly two categories of glomerulonephritis (GN) was observed. The first group was characterized by mesangial-cell proliferation either with focal features (11 dogs), or with a diffuse pattern (10 dogs). The second group (12 dogs) showed the typical findings of segmental membrano-proliferative GN; amyloid deposits were seen in the glomerular tuft and interstitium in 1 dog. Immunohistochemical investigation revealed granular deposits of IgG, IgM, and C3 both in mesangial areas as well as on glomerular capillary walls. Granular immune deposits om the tubular basement membrane were also found in 31 out of 34 dogs examined. With ultrastructural investigation, subendothelial and mesangial electron-dense deposits were revealed. Age, sex, serum creatinine, BUN, duration of disease, anti-Leishmania antibody titers, and immune complexes did not discriminate between the types of observed GN, while proteinuria did. The study shows that the renal involvement is the natural sequela in dogs infected with L. infantum, and that the kidney lesions are characterized by immunologically mediated glomerular and tubular damage.

Amyloidosis↗
PubMed1991

Ultrastructure of the cyst and life cycle of Sarcocystis sp. from wild sheep (Ovis musimon).

Sarcocystis sp. (Eimeriina: Sarcocystidae) is described as a heteroxenous coccidian with domestic dogs as an experimental definitive host and wild sheep (Ovis musimon) as natural intermediate hosts. Mature sarcocysts of this Sarcocystis sp. were examined by transmission electron microscopy. Sarcocysts in various muscle tissues were microscopic, had a thin primary cyst wall and septa and measured 81.0 x 30.5 microns. The cysts were located within muscle cells and were limited by a primary cyst wall (PCW). The cyst surface was highly folded forming densely packed projections. Between the PCW projections the surface of the cyst was marked with pit-like invaginations. The ground substance of the cyst formed a layer at the periphery of the cyst, filled the projections and formed septa which divided the cyst into compartments. Sarcocysts contained numerous bradyzoites that were 15.2 x 3 microns and few metrocytes 11.5 x 3.5 microns. Twelve days after ingesting Sarcocystis sp.-infected wild sheep meat, four dogs began passing sporocysts in their feces: two domestic cats did not pass oocysts or sporocysts after ingesting meat from the same animals. Sporocysts measured 14.8 x 9.9 microns.

Animals↗
PubMed1991

Acute hepatosis in the European brown hare (Lepus europaeus) in Italy.

Since October 1986 an unusually high mortality has been observed both in wild European brown hares (Lepus europaeus) and in hare farms in Italy. Pathological alterations, including severe hepatosis, nephrosis, congestion and hemorrhages of tracheal mucosa and lungs, and splenic vascular congestion, were observed in 179 of 381 hares necropsied from 1986 to 1988. Jaundice also was seen in 30% of these hares. Histologically, the liver damage was characterized by coagulative necrosis, mainly located around the portal areas, or by degenerative changes. Hyperemia, focal hemorrhages and periportal mononuclear cell infiltration were also present. The epithelium of renal tubules showed the presence of various degrees of vacuolar degeneration and necrosis, and eosinophilic granular hyaline casts or homogenous proteinaceous material were found within the lumen of tubules. Only the adult hares were affected. In wild hare populations night counts revealed a reduction of the number of observed wild hares during the winter period which ranged from 27 to 40%, whereas in hare farms the mortality ranged from 30 to 90%. Bacteriological, parasitological, and toxicological investigations were unable to confirm the primary cause of these deaths. Negative stain electron microscopy and immunoelectronmicroscopy conducted since October 1988 on liver and spleen homogenates from hares with acute hepatosis revealed the presence of viral particles with morphological aspects resembling those of calicivirus, antigenically related to the etiological agent of viral haemorrhagic disease of rabbits.

Acute Disease↗
PubMed1990

Giant axonal neuropathy: clinical, electrophysiologic, and neuropathologic features in two siblings.

Giant axonal neuropathy is a progressive central-peripheral axonopathy characterized by distention of axons by aggregated neurofilaments. We report two female siblings with giant axonal neuropathy. Both patients developed symptoms of a chronic progressive polyneuropathy at age 3 years. Clinical evidence of central nervous system involvement was present in both cases. Autopsy neuropathologic examination of the older sibling at the age of 11 years revealed numerous giant axons, Rosenthal fibers, and gliosis throughout the brain and spinal cord and typical giant axons in the peripheral nerves. Electrophysiologic studies in the younger sibling indicated brain stem dysfunction, and her sural nerve biopsy revealed enlarged axons packed with neurofilaments. These patients illustrate that neurologic deficits of giant axonal neuropathy result from widespread lesions in the central, as well as peripheral (including autonomic), nervous systems. This occurrence of giant axonal neuropathy in two siblings supports a genetic origin of this disease. This is the first report of autopsy findings in giant axonal neuropathy in an affected sibling.

Axons↗
PubMed1990

Concomitant syphilitic and HIV infection. A case report.

Evolution of syphilis has been studied in HIV-seropositive patients with regard to progression mode and clinical pictures. Reciprocal interactions between syphilis and HIV have been suggested based on the observation of unusually aggressive forms of treponemic infection, particularly at the CNS level. We describe a case of a 52-year-old homosexual male AIDS presenting with clinically manifest tabe dorsalis. The evolution to neurosyphilis seems, at least in this stage, to be accelerated by superimposed HIV infection.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Evaluation of Ames Seralyzer for the therapeutic drug monitoring of phenobarbital and phenytoin.

Comparison of a reflective photometry assay (Ames Seralyzer) and a fluorescence polarization immunoassay (Abbott TDx) for measuring phenobarbital and phenytoin serum concentration was performed. Routine phenobarbital and phenytoin plasma levels drawn from patients in the pediatric neurology clinic and pediatric intensive care unit were determined in duplicate by the Abbott TDx and Ames Seralyzer systems. A total of 40 samples were assayed. The interday and intraday variability of the Ames system was determined using calibrators of known concentrations (5-25 micrograms/ml). There was significant correlation between the serum phenobarbital or phenytoin concentrations when determined by the Seralyzer and TDx systems. The intraday variability for the measurement of phenytoin when determined by the Seralyzer had coefficients of variation ranging from 2.2 to 8.9%. The interday variability for phenytoin when measured by both the TDx and the Seralyzer correlated well with known calibrators. The utility of the Ames Seralyzer for acute-care facilities, physician offices, and pharmacy satellites is apparent. Based on statistical analysis, the Seralyzer provides accurate phenobarbital and phenytoin serum measurements for clinical use in therapeutic drug monitoring.

Adolescent↗