PubMed Health⌕ Search

Biomedical subjects

M Miceli

Publications and source records attributed to M Miceli.

At least 55 records · Page 3Linked to original sources
PubMed1989

HIV genome in peripheral blood mononuclear cells of seronegative regular sexual partners of HIV-infected subjects.

We have investigated the presence of the human immunodeficiency virus (HIV) by using in situ hybridization on peripheral blood mononuclear cells (PBMCs) from seronegative regular sexual partners of HIV-infected subjects. The cells were hybridized with a 9 kilobase (kb) Sstl-Sstl lambda BH 10 probe, which was able to recognize both viral mRNA and proviral cDNA. Labeling was done by chemical insertion of an antigenic sulfone group in cytosine moieties and was visualized by a double-antibody immunohistochemical reaction. In all the subjects studied, the HIV genome was present. The HIV infected cells showed morphological aspects consistent with that of lymphocytes and monocytes. Our data suggest that the anti-HIV seronegative individuals who are regular sexual partners of HIV-infected subjects may be HIV-infected.

Bisexuality↗
PubMed1989

Relationship between age and anterograde refractoriness of the accessory pathway in Wolff-Parkinson-White patients.

In 22 patients (age range 13-40 years) with Wolff-Parkinson-White ECG pattern without evidence of associated cardiomyopathy we measured the anterograde effective refractory period of the accessory pathway (ERP-AP) by extrastimulus method (at twice diastolic threshold) during atrial pacing (100/min). The ERP-AP range was 220-480 ms. There was a significant direct correlation between age and ERP-AP (r = 0.50, p less than 0.01). An ERP-AP less than or equal to 250 ms was found in 4 patients (age less than or equal to 23 years). This is noteworthy in the light of reports that, over the years: (1) typical Wolff-Parkinson-White ECG signs can disappear and (2) the frequency of tachycardic episodes decreases. Our data suggest a lower risk of high ventricular rates during atrial fibrillation with increasing age.

Adolescent↗
PubMed1989

[Retrospective analysis of 31 cases of soft tissue tumors. Comparison of MR and surgical and anatomo-pathological findings].

Twenty-five patients (16 with malignant soft-tissue tumors and 9 with suspected recurrence), previously studied with conventional radiography and Computed Tomography (CT), were examined with Magnetic Resonance (MR) imaging. MR findings were surgically and anatomo-histopathologically confirmed. Six more patients with benign lesions were examined for differential diagnosis. MR capabilities are here evaluated to detect and eventually characterize the lesion, and to assess its exact location. No false positives were found, and there was only one false negative, in a case of recurrent Malignant Fibrous Histiocytoma (MFH). In another case of MFH the infiltration of the adjacent vessels and nerves was not imaged. After a careful review of all the examinations, MR imaging appears to be able to provide much information for surgical planning about tumor extent and margins, thanks to its contrast resolution between tumor and surrounding anatomical structures. Therefore, MR imaging can be reasonably employed as the examination of choice when a soft-tissue tumor is clinically suspected, because of the multi-planar images it provides with and of its differential imaging parameters.

Adolescent↗
PubMed1989

Experimental evaluation of perfluorophenanthrene as a high specific gravity vitreous substitute: a preliminary report.

Perfluorophenanthrene, a liquid fluorocarbon with a specific gravity approximately twice that of water, potentially offers certain advantages as a vitreous substitute in vitreoretinal surgery. To determine its efficacy and safety we first purified it by chemical methods used in the preparation of experimental blood substitutes to a level at which it was not at all or only minimally toxic to culture-grown retinoblastoma cells. Nineteen of 22 vitrectomized eyes of white New Zealand rabbits injected with this purified perfluorophenanthrene showed satisfactory clinical tolerance. Light and electron microscopy showed minimal or no toxic effects in the 19 eyes, although uptake of perfluorophenanthrene by some preretinal cells was observed 28 days after implantation. Postoperative light-adapted electroretinography recordings of eight of the injected eyes showed no significant change. Perfluorophenanthrene injected into the anterior chamber of the rabbit eyes had toxic effects on the cornea. If further experimentations confirm our findings, perfluorophenanthrene may be a suitable transparent high-density liquid for temporary use in surgery to repair retinal detachments.

Animals↗
PubMed1986

Synthesis of disulfide-bonded outer membrane proteins during the developmental cycle of Chlamydia psittaci and Chlamydia trachomatis.

The disulfide bond cross-linked major outer membrane protein (MOMP) of the extracellular elementary bodies (EBs) of Chlamydia psittaci was reduced to its monomeric form within 1 h of entry of EBs into host cells by a process which was inhibited by chloramphenicol, while monomeric forms of three cross-linked cysteine-rich proteins could not be detected in Sarkosyl outer membrane complexes at any time in either extracellular or intracellular forms of C. psittaci. Synthesis and incorporation of the MOMP into outer membrane complexes were detected early in the infection cycle (12 h postinfection), while synthesis and incorporation of the cysteine-rich proteins were not observed until reticulate bodies had begun to reorganize into EBs at 20 to 22 h postinfection. By 46 h postinfection, the intracellular population of C. psittaci consisted mainly of EBs, the outer membrane complexes of which were replete with monomeric MOMP and cross-linked cysteine-rich proteins. Upon lysis of infected cells at 46 h, the MOMP was rapidly cross-linked, and infectious EBs were released. The status of the MOMP of intracellular Chlamydia trachomatis was similar to the status of the MOMP of C. psittaci in that the MOMP was largely uncross-linked at 24 and 48 h postinfection, but formed interpeptide disulfide bonds when it was exposed to an extracellular environment late in the developmental cycle. In contrast to C. psittaci, only a fraction of the cross-linked MOMP of infecting EBs of C. trachomatis was reduced by 4 h postinfection, and reduction of the MOMP was not inhibited by chloramphenicol. Exposure of extracellular EBs of C. trachomatis and C. psittaci to dithiothreitol reduced the MOMP but failed to stimulate metabolic activities normally associated with reticulate bodies.

Bacterial Outer Membrane Proteins↗
PubMed1986

[Correlation between plasma concentration of heparin and biological response determined by 2 APTT reagents of different sensitivities].

Among 56 patients with elevated thromboembolic risk, subject to intravenous infusion of heparin, we have determined the relation between hematic concentration of heparin and activated partial thromboplastin time (APTT), surveyed by two reagents with different sensitivity. The obtained results shown a very good correspondence without significant differences between the APTT reagents used, especially inside the therapeutic range. Otherwise a good correlation is demonstrated between methods, relative to two different chromogenic substrates, applied to heparin determination.

Aged↗
PubMed1985

Synthesis of protein in host-free reticulate bodies of Chlamydia psittaci and Chlamydia trachomatis.

Synthesis of protein by the obligate intracellular parasitic bacteria Chlamydia psittaci (6BC) and Chlamydia trachomatis (serovar L2) isolated from host cells (host-free chlamydiae) was demonstrated for the first time. Incorporation of [35S]methionine and [35S]cysteine into trichloroacetic acid-precipitable material by reticulate bodies of chlamydiae persisted for 2 h and was dependent upon a exogenous source of ATP, an ATP-regenerating system, and potassium or sodium ions. Magnesium ions and amino acids stimulated synthesis; chloramphenicol, rifampin, oligomycin, and carbonyl cyanide p-trifluoromethoxyphenylhydrazone (a proton ionophore) inhibited incorporation. Ribonucleoside triphosphates (other than ATP) had little stimulatory effect. The optimum pH for host-free synthesis was between 7.0 and 7.5. The molecular weights of proteins synthesized by host-free reticulate bodies closely resembled the molecular weights of proteins synthesized by reticulate bodies in an intracellular environment, and included outer membrane proteins. Elementary bodies of chlamydiae were unable to synthesize protein even when incubated in the presence of 10 mM dithiothreitol, a reducing agent which converted the highly disulfide bond cross-linked major outer membrane protein to monomeric form.

Bacterial Outer Membrane Proteins↗
PubMed1984

31P-NMR studies of the freeze-tolerant larvae of the gall fly, Eurosta solidaginis.

31P NMR was applied to an examination of the freeze-tolerant larvae of the gall fly, Eurosta solidaginis. Resonances from sugar phosphates, inorganic phosphate, adenylates and arginine phosphate were identified. Two peaks of Pi were identified corresponding to intracellular and extracellular Pi. Anoxia produced an expected decrease in peak intensities of ATP and arginine phosphate while the peak of intracellular Pi was enhanced and shifted to indicate intracellular acidification during anoxia. Spectra of whole larvae were monitored over a temperature range from -30 degrees to +25 degrees C. No abrupt alterations in the spectra were seen at the point of extracellular freezing which occurs at about -8 degrees C but temperature had dramatic effects upon the peak intensities of ATP and arginine phosphate. A reversible increase/decrease in peak intensities, relative to Pi, was observed as temperature was raised/lowered. At 15 degrees and -20 degrees C, the beta peak of ATP was 64% and 2% of the peak intensity of Pi while that of arginine phosphate was 78% and 11%, respectively. This temperature effect was not an artifact of instrumentation (as model solutions containing Pi, ATP and arginine phosphate did not show this effect) or a result of changes in the total amounts of these compounds in the cell with temperature. Rather it is apparent that these molecules become restricted in their rotational movement as temperature is lowered perhaps via binding to subcellular components. Changes in the amounts of freely soluble ATP and arginine phosphate with temperature could have important implications for metabolism and its control. Analysis of the effect of temperature on the chemical shift of Pi was also used to determine pH in the intracellular and extracellular compartments. Temperature change had no effect on extracellular (hemolymph) pH which remained constant at 6.1-6.3. Intracellular pH varied with temperature, however, from pH 6.8 at 15 degrees C to pH 7.3 at -12 degrees C with a change, delta pH/delta 0, of -0.0185 degrees C consistent with alphastat regulation.

Adenosine Triphosphate↗
PubMed1983

Lesions of the medial preoptic area prevent the facilitation of maternal behavior produced by amygdala lesions.

In the present study we tested the hypothesis that the facilitation of maternal behavior produced by amygdala lesions is mediated through the medial preoptic area. Different groups of animals sustained lesions of the corticomedial amygdala (Group AM), the medial preoptic area (Group MPOA), both regions (Group AM-MPOA), the corticomedial amygdala and non MPOA control sites (Group AM-CX), and control sites (Groups LC or SC). Animals were tested for their maternal responses to foster pups presented daily for an 11 day period. It was found that groups sustaining lesions of the amygdala (Group AM and AM-CX) became maternal more rapidly than did Control Groups (LC and SC), Group MPOA, and Group AM-POA. However, animals in Group AM-POA were similar to Groups AM and AM-CX in that they did not avoid pups, whereas groups not sustaining lesions of the amygdala did. These results, taken together, suggest that amygdala-induced facilitation of maternal behavior in the nulliparous females is mediated through the MPOA. They suggest, moreover, the primary effect of removing the amygdala is to reduce avoidance of pups, with only secondary effects on maternal responsiveness.

Amygdala↗
PubMed1983

Effects of diet on feeding and body weight regulation during pregnancy and lactation in the golden hamster (Mesocricetus auratus).

The hypothesis was tested that the weight loss shown by lactating hamsters constitutes a "regulated" weight loss. The results support the hypothesis: Prefattened overweight hamsters lost more weight from the time of mating to the end of lactation than did unmanipulated controls. However, the weight loss during lactation was reduced by giving hamsters access to a high-fat diet, a result indicating that a portion of the lactational weight loss may also be regulated by the diet provided. When lactating hamsters were given access to a fractionated diet consisting of pure fat, pure carbohydrate, or 45% protein, they increased their proportional intake of both protein and fat but not of carbohydrate. These studies show that hamsters differ from rats in their pattern of energy regulation during pregnancy, lactation, and the postsuckling period. Reasons for these species differences are discussed.

Animals↗
PubMedDate not supplied

Synthesis and antiplatelet activity of some 3-phenyl-1,8-naphthyridine derivatives.

A series of 2-cycloalkylamino-3-phenyl-1,8-naphthyridine derivatives, variously substituted in the 6- and 7-positions were synthesized and tested for their ability to inhibit human platelet aggregation in vitro induced by arachidonate, collagen and ADP. Compounds 5a,b, 7a,b, 8a and 10c,d showed a remarkable activity similar to that of indomethacin in the test with arachidonate and collagen. In the test with ADP only compound 8a showed a significant activity. The presence of a morpholinyl or piperidinyl group in position 2 and of a chloro or methoxy group in position 7 of the 1,8-naphthyridine nucleus seem to favour a higher activity. However on the basis of the pharmacological results, no structure-activity relationship can be deduced. Compounds 5b and 7b, which possess the best activity in the arachidonate test, were also shown to increase the c-AMP level significantly, without involving the adenylyl cyclase system.

Blood Platelets↗
PubMedDate not supplied

Elevated alanine aminotransferase in blood donors: role of different factors and multiple viral infections.

Many different aetiological agents stimulate alanine aminotransferase (ALT) production. Viral markers and other aetiologies were investigated in 2166 individuals, randomly selected from 10,000 consecutive blood donors. Elevation of ALT was found in 10.8% of subjects. Grouping donors according to ALT level and correlating with, respectively, hepatitis B core antibody (HBcAb), cytomegalovirus antibody alone, or associated with HBcAb, showed similar findings (high ALT 11.1%, normal 11.6%; high 85.4%, normal 81.4%; high 10.2%, normal 11.0%, respectively). Hepatitis C virus (HCV) antibody was found to be significantly associated with elevated ALT levels (high 1.7%, normal 0.26%). Other causes of ALT elevation were alcohol abuse (17%), obesity (25%) and dyslipidaemia (38%), but in 11% there was no obvious aetiology. Although HCV is a rare cause of elevated ALT in blood donors, it seems to be the only virus, among those tested, to account for liver damage. This may be due to the non-protective role of HCV antibody, the low specificity of ALT, or the pathogenic role of uninvestigated viruses.

Alanine Transaminase↗
PubMedDate not supplied

[Socioeconomic inequalities in health care efficacy. Three examples in Lazio region].

There has been a limited number of studies in Italy investigating the relationship between socioeconomic inequalities and efficacy of treatments. This paper reviews three case studies on the association between socioeconomic status and disease outcome in the Lazio Region, Italy. The studies investigated: a) the probability of renal transplantation among patients with endstage renal disease; b) the survival of AIDS patients before and after the introduction of the new antiretroviral therapies; c) the 30-day mortality of patients who underwent coronary artery bypass graft surgery. The three studies demonstrate the complex relationship between socioeconomic status and both access to, and efficacy of, important health interventions.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

[Collaborative study on peritoneal dialysis (PD) as first dialysis treatment in an Italian region: 1994-2000].

BACKGROUND: In Lazio, only about 5% of uremic patients are on peritoneal dialysis (PD). The present study focuses on the parameters of PD selection, the treatment schedules, and the clinical outcomes of PD patients in the nine public facilities offering a PD program. A cohort of 249 first-time PD patients, from July 1, 1994 to December 31, 2000, was retrospectively considered. METHODS: For the enrollment of the patients, the Regional Dialysis Registry databank was consulted. On December 31, 2000, a systematic review of patient charts was performed to extract the reasons for the PD choice, details of PD schedule, peritonitis episodes, reasons for drop-out, and patient survival rates. In regard to technique success-defined as the probability of having a patient alive on PD-change of modality and death were considered as final events. In regard to patient survival, only death, even in the first 2 months after a shift to hemodialysis, was considered the end point. RESULT: The main PD selection reasons were patient and/or nephrologist preference in 90% of cases. One-hundred eighty-nine patients (76%) had been started on CAPD. During the follow-up, 38.2% dialysis schedules had been modified at least once. At the end of follow-up, 41.2% patients were on APD. The peritonitis rate was one episode per 30 patient-months (1 per 27 patient-months in CAPD; 1 per 37 patient-months in APD; p = 0.08). The technique success rate was 66.3% after 2 years and 49.8% after 3 years. The patient survival rate was 81.1% after 2 years and 68.7% after 3 years. CONCLUSIONS: Patients chose PD as a first dialysis treatment mainly because of reasons unrelated to their clinical status. The technique's success, patient mortality rates, and the peritonitis rate do not explain the low PD diffusion in the region. The peritonitis rate meets the target criteria for excellence recommended by the Italian Society of Nephrology. The observed outcomes may have been favored by the selection of motivated patients and by the increased use of APD.

Adult↗