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Biomedical subjects

T Rossi

Publications and source records attributed to T Rossi.

At least 37 records · Page 2Linked to original sources

Correlation between high intake of glycyrrhizin and myolysis of the papillary muscles: an experimental in vivo study.

The ingestion of large quantities of glycyrrhizin, whether as a drug or a sweetener, is known, in susceptible subjects, to induce a syndrome similar to hypermineralcorticoidism, with bouts of hypertension, hypokaliaemia and rabdomyolysis, sometimes associated with severe renal failure and hypokaliaemia-induced arrythmias. Glycyrrhizin is also known to isomerize into the glycyrrhetic (or glycyrrhetinic) acids 18alpha- and 18beta-. In previous works, we reported that these metabolites cause bouts of hypertension and reduction in diuresis at low doses in the rat. In particular, the alpha isomer causes significant elimination of the calcium ion in the urine. The present findings confirm that 18alpha-glycyrrhetic acid is more toxic than either glycyrrhizin or the beta isomer. Histopathological study of tissue samples taken from rats treated with the alpha isomer also reveal selective damage to the myocardium with oedema, myolysis, apoptosis and blistering of the sarcoplasm. These effects begin to appear in the course of subchronic treatment, they manifest themselves in acute treatment and correlate closely with the electrocardiographic changes recorded in rats acutely treated with 18alpha-glycyrrhetic acid.

Animals↗

[Intra-spermatic L-carnitine and survival of sperm motility].

BACKGROUND: The aim of this work was to evaluate the intrasperm carnitine (L-C) content related to sperm motility survival in bovine cervical mucus and in culture medium (Tyrode solution). METHODS: The following subjects were selected: 15 fertile normospermic subjects (according to WHO guidelines) and 31 male partners of infertile couples (semen profile: volume > 2.0 ml; concentration > 20 x 10(6)/ml, progressive motility > or = 25% (WHO categories "a" and "b") after fluidification, abnormal forms < 70%; round cells < 1.0 x 10(6)/ml). After standard semen analysis, the samples were subdivided into three aliquots in order to carry out: a) intrasperm L-C (free, total and acetylated) assay; b) sperm motility survival in bovine cervical mucus; c) sperm motility survival in culture medium. RESULTS: A strict correlation was found between L-C (total and acetylated) content and motility survival in cervical mucus. This is probably due to the fact that in cervical mucus lipids are an important energy source for sperm and to metabolize these lipids intrasperm L-C is essential. Therefore, L-C content can be considered as an indicator of sperm motility life-span in cervical mucus. A significant correlation, even if reduced compared with cervical mucus, was also observed between L-C (total and acetylated) content and sperm motility survival in the biological medium. This probably is because the L-C system modulates the reserves of free CoA, essential to the tricarboxylic acid cycle function. CONCLUSIONS: The intrasperm L-C deficit could be due to; a) alterations in the L-C uptake mechanisms in the epididimys due to inflammatory processes; b) lack of testosterone (L-C uptake is androgen-dependent). Therefore, the therapeutic implication of this finding is that where hypomotility is due to intrasperm L-C deficit, exogenous L-C administration or improvement of L-C epididymal testosterone-dependent uptake could promote the acquisition of sperm motility.

Animals↗

Semen analysis and seminal plasma biochemistry in two brothers with familial reciprocal translocation 46,XY,t(8;9)(p10;p10) transmitted by the father.

Here we report familial balanced translocation (46,XY,t(8;9)(p10;p10) inherited by two brothers from the father. The first subject, 33 years old, was examined after 3 years of childless marriage. Semen analysis showed severe oligozoospermia, hypomotility and teratozoospermia. His brother, 29 years old, volunteered to join this study. He had not yet tried to start a family. Semen analysis showed dyspermia, but the condition was much less serious than his brother's. In both subjects, the secretory function of the epididymis and the genital tract accessory glands did not seem to be affected by this particular translocation. This case report highlights the importance of cytogenetic analysis in dealing with infertile patients suffering from severe dyspermia apparently sine causa. This is particularly the case when certain Assisted Reproductive Technology (ART) programs are recommended, where natural selection of the sperm no longer takes place (e.g. ICSI). The possible risk of an increase in fetal chromosomal abnormalities would suggest genetic counselling in all such situations.

Adult↗

Growth of preterm infants with cystic periventricular leukomalacia.

Etiology of the high rates of growth failure in children with cerebral palsy (CP) remains unclear. The purpose of this study was to evaluate the relation between growth failure in preterm infants with cystic periventricular leukomalacia (CPVL) and neonatal health complications. The population consisted of all preterm infants (51) with a gestational age of <33 weeks who were admitted to the Children's Hospital of Buffalo from 1988 to 1993 and who had CPVL. Out of the 41 survivors with CPVL who were followed, 39 developed CP and 18 developed growth failure during infancy. At the time of greatest growth failure, the majority (72%) of infants had signs of undernutrition as defined by the Waterlow (1972) classification. Oral feeding impairment was the sole risk factor for the occurrence of growth failure. Undernutrition appears to be important in the occurrence of growth failure in preterm infants with CPVL and CP.

Anthropometry↗

Synthesis, antiviral and antiproliferative activity of some N-benzenesulphonyl-2(2- or 3-pyridylethyl)-benzimidazoles.

Some N-benzenesulphonyl-2(2- or 3-pyridylethyl)-benzimidazoles were synthesized and tested in vitro for antiproliferative and antiviral activity. Only one compound displayed a degree of antiproliferative activity against chronic myeloid leukaemia cells. However, a number of them exerted an antiviral effect at micromolar concentrations. The antiproliferative activity and the maximum potency of antiviral activity correlate with the presence of both the 2-pyridyl moiety bound at the ethylenic bridge in C-2 of benzimidazole and the nitro group in the benzene ring.

Animals↗

Pars plana vitrectomy for retinal detachment due to internal posterior ophthalmomyiasis after cataract extraction.

BACKGROUND: The authors report a case of posterior internal ophthalmomyiasis causing vitreous haemorrhage and retinal detachment after uncomplicated cataract extraction. CASE REPORT: The patient suffered an abrupt vitreous haemorrhage 9 days after ECCE and posterior chamber IOL implantation. After 2 months the haemorrhage did not clear up and a retinal detachment arose. The patient underwent encircling scleral buckle, pars plana vitrectomy and fluid-gas exchange. In course of intervention the surgeon removed from the vitreous chamber a 14-mm-long round worm subsequently identified as a dipterous larva of the Sarcophagidae family. DISCUSSION: The patient showed no sign of subretinal tracking or retinal breaks or holes. The sclerocorneal surgical wound seems the most likely site of entrance of the parasite, and this would then be the first reported case of myiasis with no RPE tracking.

Aged↗

The application of the differential pH method to the biochemical evaluation of seminal plasma.

OBJECTIVE: To apply the differential pH method to the biochemical evaluation of seminal plasma. DESIGN AND METHODS: Fructose, citric acid and free L-carnitine concentration in human seminal plasma were measured by the differential pH method. These are routinely taken as markers of seminal vesicle, prostate and epididymal function, respectively. The pH differential method was then compared with standard spectrophotometry. RESULTS: The linearity, recovery and imprecision calculation for each assay were found to be reliable and the method correlated well with the reference spectrophotometric technique. In addition, the pH differential method showed certain advantages compared to spectrophotometry: a) speed of procedure (40 to 120 sec/assay); b) ability to measure the analytes even in small volumes of seminal plasma (10 microL to 50 microL) without deproteinization or dilution, thus eliminating manual operations. CONCLUSIONS: The differential pH method is an innovative approach to the biochemical assessment of seminal plasma.

Carnitine↗

In-vitro studies of two 5-nitroimidazole derivatives.

This paper reports the findings obtained using two new compounds belonging to the 5-nitroimidazole family: sulphuridazole (V1) and sulphonidazole (V2). We first assessed their antimicrobial activity on Clostridia spp. and then extended the study to Gram-positive and Gram-negative aerobic microorganisms and to Candida albicans. Their MICs were compared with those of metronidazole. The findings show that the antibacterial and antimycotic activity of sulphonidazole is greater than that of sulphuridazole, while metronidazole is not active against any aerobic organism. It also emerges that the NO2 group is indispensable for all the microorganisms assayed and that sulphuridazole and sulphonidazole are the first two 5-nitroimidazoles active against C. albicans. The redox potentials of the 5-nitroimidozoles studied suggest that their action mechanism is mainly based on redox processes.

Anti-Bacterial Agents↗

The use of panoramic viewing system in relaxing retinotomy and retinectomy.

BACKGROUND: Retinotomies and retinectomies are surgical procedures mainly devoted to the peripheral retina that require optimal visibility and adequate magnification to make the surgeon's task easy, quick, and safe. The purpose of present study was to estimate to what extent the introduction of wide-angle viewing systems can help the surgeon perform safer and more effective retinotomy procedures. MATERIALS AND METHODS: The authors retrospectively analyzed the records of patients undergoing retinotomy procedures between 1993 and 1995 and divided them into two groups according to the viewing system used during the retinotomy procedures. Group 1 included 86 eyes that underwent surgery between July 1991 and June 1993 with Lander's plano-concave and prismatic lenses (Optikon, Rome, Italy), and group 2 included 96 eyes that underwent surgery between July 1993 and June 1995 with the Advanced Vitreoretinal Instruments system (New York, NY). Outcome measures were divided into preoperative (diagnosis at baseline, anterior proliferative vitreoretinopathy grade and extension, and visual acuity), intraoperative (size of retinotomy, number of laser spots, need for scleral depression, lensectomy, intraocular lens and capsule removal, and duration of treatment) and postoperative (anatomic success rates, visual acuity, postoperative intraocular pressure, and need for postoperative laser treatment and follow-up treatment). RESULTS: Among preoperative parameters, there were no significant differences between the two groups. For intraoperative parameters, eyes in group 2 underwent significantly shorter surgical procedures, had less of a need for scleral depression, and, as a group, had a higher average number of laser spots. For postoperative parameters, eyes in group 2 had a significantly lower need for laser treatment at the edge of retinotomy after surgery. CONCLUSION: Our results suggest that the use of a panoramic viewing system significantly decreases the time required for intervention, allowing more complete laser treatment along the edge of the retinotomy and lowering the need for scleral depression. The need for completion of laser treatment along the edge of the retinotomy after surgery also is reduced significantly, possibly increasing patient comfort because, especially in the early postoperative days, postoperative laser treatment can be extremely uncomfortable for the patient and difficult to perform for the surgeon. No prognostic benefit has been proven for any of the two groups because anatomic and visual results were overlapped.

Follow-Up Studies↗

Scanning laser ophthalmoscopy in the early diagnosis of vitreoretinal interface syndrome.

BACKGROUND: The purpose of this study was to estimate if and to what extent scanning laser ophthalmoscopy can help in the early diagnosis and follow-up management of the vitreoretinal interface syndrome, which includes disorders such as cellophane maculopathy, pseudomacular hole, macular pucker, and macular hole. METHODS: The 35 fellow eyes of 35 patients with vitreoretinal interface syndromes in the first eye underwent scanning laser ophthalmoscopy microperimetry and argon, helium-neon, and infrared scanning laser ophthalmoscopy. Fellow eyes were defined as clinically positive or negative for vitreoretinal interface syndrome. Fellow eyes then were classified based on scanning laser ophthalmoscopy techniques. Patients were observed for an average of 18 months (range, 10-26 months). RESULTS: Thirty-two of the 35 fellow eyes were classified as clinically negative, and three of the 35 were classified as clinically positive. Fifteen of the 32 clinically negative fellow eyes were redefined as positive on scanning laser ophthalmoscopy. None of the clinically positive eyes proved to be negative on scanning laser ophthalmoscopy. During the average follow-up period (18 months), the condition of five of 18 fellow eyes that were positive on scanning laser ophthalmoscopy worsened. None of the 17 eyes that were negative on scanning laser ophthalmoscopy worsened. CONCLUSION: Scanning laser ophthalmoscopy can produce beautifully clear images of structures that are otherwise difficult to see and document, such as posterior hyaloid and the inner retinal layers. Despite a relatively limited number of cases and the short duration of the follow-up period, the present study suggests that scanning laser ophthalmoscopy has good sensitivity and specificity for the early diagnosis of vitreoretinal interface syndromes.

Eye Diseases↗

[Seminal and biochemical features in a subject with male phenotype and 46, XX genotype].

Semen parameters and biochemical seminal markers in a 46,XX male subject were evaluated; Southern blot analysis with Y-DNA probes showed the absence of the SRY (Sex-determining Region of Y). The semen analysis, carried out three times, showed azoospermia, reduced volume (< 0.5 ml) and reduced pH value. Assays of the biochemical markers of the genital tract gave a profile very similar to that seen in cases of blockage of the ejaculatory ducts. This is probably due to inadequate differentiation of the genital tract adnexal glands leading to aplasia of the seminal vesicles. As a consequence, the ejaculate is formed of prostatic fluid only. The authors would underline the difficulties of counselling these subjects. This is particularly difficult where, as in this case, the genetic diagnosis is carried out in adulthood. In addition to the psychological stress of confirmed sterility, the patient must inevitably undergo the trauma of questioning his sexual identity.

Adult↗

Eradication of the long-term carriage of methicillin-resistant Staphylococcus aureus in patients wearing dentures: a follow-up of 10 patients.

To cure the long-term carriage of methicillin-resistant Staphylococcus aureus (MRSA), eradication treatment was given to 10 patients wearing complete dentures. In addition to multiple body sites, MRSA was cultured from the dentures of six patients. The contaminated dentures were rebased and sterilized with heat in order to prevent recolonization. The patients did not use their dentures during the decolonization therapy. Subsequently, MRSA was eradicated from three of these patients but three others remained MRSA-positive despite at least two courses of combined systemic and topical eradication treatment. These particular patients had persistent stomatitis and their dentures were a poor fit, in poor condition and repeatedly grew MRSA. Eradication treatment was successful in the remaining four patients whose dentures were MRSA-negative. These results confirm that dentures may function as foreign bodies and sustain persistent nasopharyngeal. MRSA colonization. Therefore, we suggest that whenever eradication of MRSA is deemed necessary in cases of nasal, oral or pharyngeal carriage, heat treatment of the dentures should be included. Further comparative studies with larger patient populations are needed to evaluate the contribution of dentures to the long-term carriage of MRSA, as well as to assess the value of denture sterilization during the eradication course.

Aged↗

Detection of group C rotavirus in infants with extrahepatic biliary atresia.

The purpose of this retrospective study was to examine liver tissue from patients with cholestatic disease for the presence of group C rotavirus RNA. The reverse transcriptase-polymerase chain reaction (PCR) for genes 5 and 6 was used, and the PCR products were subjected to liquid hybridization with a 32P-labeled probe. A second amplification with nested primers was also used. Samples from 32 subjects (20 with biliary atresia or choledochal cyst and 12 controls) were tested. Ten of 20 biliary atresia patients were positive for group C rotavirus RNA; no controls were positive (P < .003). Three of the positive patients were positive for both genes 5 and 6. Six of the 10 had > 1 sample that was positive. These data suggest a possible relationship between group C rotavirus and extrahepatic biliary atresia in the 10 patients in whom virus RNA was detected.

Autoradiography↗

Semen analysis in HIV seropositive men and in subjects at high risk for HIV infection.

The main purpose of this research was (i) to perform a comparative study of sperm parameters in human immunodeficiency virus (HIV) seropositive and high risk subjects in order to identify any possible alterations in the semen which specifically result from HIV infection and (ii) to study the p24 antigen as an early diagnostic marker of infection in high risk subjects. HIV seropositive subjects showed no significant variations regarding sperm densities, motility and viscosity compared to high risk subjects and controls. On the other hand, these HIV seropositive subjects showed (a) a significantly higher percentage of cytoplasmic droplet forms and immature germ cells, perhaps caused by an early failure of epididymal function and/or by a condition of stress affecting spermatogenesis after HIV infection and (b) a significantly higher level of spermiophage cells, suggesting that HIV activates mechanisms that increase spermiophagy. In addition, HIV seropositive men showed a significant positive correlation between blood CD4+ and sperm motility as well as a significant inverse correlation between CD4+ and sperm abnormalities. This is perhaps due to a decrease in testosteronaemia leading to defective epididymal sperm maturation. To date, p24 has not been found in the serum or seminal plasma of high risk subjects. The longitudinal study in progress should provide further information on this point.

Adult↗

Osteoid osteoma of the calcaneus: an unusual cause of hindfoot pain in an adolescent athlete.

Osteoid osteomas are distinctive, benign tumors of bone that cause localized pain. This problem, although rare in athletes, must be resolved before pain-free competition can resume. We present a case of a 14-year-old white, male football player who complained of heel pain. He was treated conservatively with ice, stretching, and a nonsteroidal anti-inflammatory drug (Advil). Postseason, his symptoms worsened and he was referred for orthopedic consultation. Radiography displayed a possible osteoid osteoma; a CT evaluation confirmed the diagnosis. The athlete was treated surgically for the condition, and following a 2-week immobilization and a 3-week rehabilitation program, the pain completely resolved.

Journal Article↗

Degradation of lyophilized and reconstituted MACROSCINT (DTPA-IgG): precipitation vs. glucosylation.

Diethylenetriaminepentaacetic anhydride (DTPA) conjugated to IgG (DTPA-IgG) and labeled with 111In is useful for detecting focal sites of infection and inflammation (R.H. Rubin, A.J. Fischman, R.J. Callahan, B. Khaw, F. Keech, M. Ahmad, R. Wilkinson and H.W. Strauss, 111In-labeled nonspecific immunoglobulin scanning in the detection of focal infection, N. Engl. J. Med., 321 (1989) 935-940). MACROSCINT contains DTPA-IgG formulated as a lyophile from a citrate buffer containing maltose. Exposure of both reconstituted and lyophilized MACROSCINT to intense light resulted in degradation primarily via formation of precipitating aggregates. However, lyophilized and reconstituted MACROSCINT responded differently to thermal stress. Reconstituted MACROSCINT subjected to thermal stress (65 degrees C) also degraded through formation of precipitating aggregates. In contrast, exposure of lyophilized MACROSCINT to thermal stress (65 degrees C) resulted primarily in an increase in the molecular size of the MACROSCINT DTPA-IgG monomer. This increase in molecular size was a function of both the moisture content in the vial and the amount of time for which the sample was stressed, but was not a function of the conjugation with DTPA. Monosaccharide analysis of the samples demonstrated that this increase in molecular size corresponded to an increase in the amount of glucose covalently attached to the IgG. These data suggest that the increase in molecular size as a function of thermal stress is due to the covalent attachment of maltose, which is a glucose disaccharide present in the lyophile as an excipient, to the IgG. This degradation pathway was only observed in the lyophile.

Chemical Precipitation↗