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Biomedical subjects

R Romano

Publications and source records attributed to R Romano.

At least 19 recordsLinked to original sources
PubMed2001

The relationship between 1H-NMR mobile lipid intensity and cholesterol in two human tumor multidrug resistant cell lines (MCF-7 and LoVo).

The high resolution proton nuclear magnetic resonance (1H-NMR) spectra of two different cell lines exhibiting multidrug resistance (MDR) as demonstrated by the expression of the well-known energy-driven, membrane-bound 170 kDa P-glycoprotein pump known as Pgp were investigated. In particular, the mobile lipid (ML) profile, and the growth and biochemical characteristics of MCF-7 (human mammary carcinoma) and LoVo (human colon adenocarcinoma) sensitive and resistant tumor cells were compared. The results indicate that both MCF-7 and LoVo resistant cells have a higher ML intensity than their respective sensitive counterparts. However, since sensitive and resistant cells of each pair grow in the same manner, variations in growth characteristics do not appear to be the cause of the ML changes as has been suggested by other authors in non-resistant tumor cells. In order to investigate further the origin of the ML changes, lipid analyses were conducted in sensitive and resistant cell types. The results of these experiments show that resistant cells of both cell types have a greater amount of esterified cholesterol and saturated cholesteryl ester and triglyceride fatty acid than their sensitive counterparts. From a thorough analysis of the data obtained in this paper utilizing numerous techniques including biological, biophysical and biochemical ones, it is hypothesized that cholesterol and triglyceride play a pivotal role in inducing changes in NMR ML signals. The importance of these lipid variations in MDR is discussed in view of the controversy regarding the origin of ML signals and the paramount role played by the Pgp pump in resistance.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

Depressive symptoms in children and adolescents with dysthymic disorder.

This report examines clinical features of 'pure' dysthymic disorder (DD, without superimposed major depressive disorder, MDD) in a sample of children and adolescents. Profiles of symptomatology and comorbidity as a function of age and gender are described. The sample consisted of 48 subjects (22 males, 26 females, age range 7-18 years, mean age 12.1 years) screened from consecutively referred children and adolescents. All subjects were comprehensively diagnosed with structured diagnostic interviews (Schedule for Affective Disorders and Schizophrenia for School Age, Diagnostic Interview for Children and Adolescents-Revised), according to DSM-IV criteria. Depressed mood, irritability, loss of energy and fatigue, guilt and low self-esteem were present in more than 70% of the subjects. Differences in symptomatic profile between males and females were not significant. Children showed less symptoms than adolescents, but the symptomatic profile was comparable (only anhedonia was significantly more frequent in adolescents). Anxiety disorders were more commonly comorbid with DD, especially separation anxiety disorder in children (33%) and generalised anxiety disorder in adolescents (67%). Externalising disorders were less frequently represented in our sample (14%). An early diagnosis of 'pure' DD before the first episode of MDD is crucial for a timely intervention.

Adolescent↗
PubMed2001

Oxidative and glycogenolytic cCapacities within the developing chick heart.

Cardiac morphogenesis and function are known to depend on both aerobic and anaerobic energy-producing pathways. However, the relative contribution of mitochondrial oxidation and glycogenolysis, as well as the determining factors of oxygen demand in the distinct chambers of the embryonic heart, remains to be investigated. Spontaneously beating hearts isolated from stage 11, 20, and 24HH chick embryos were maintained in vitro under controlled metabolic conditions. O(2) uptake and glycogenolytic rate were determined in atrium, ventricle, and conotruncus in the absence or presence of glucose. Oxidative capacity ranged from 0.2 to 0.5 nmol O(2)/(h.microg protein), did not depend on exogenous glucose, and was the highest in atria at stage 20HH. However, the highest reserves of oxidative capacity, assessed by mitochondrial uncoupling, were found at the youngest stage and in conotruncus, representing 75 to 130% of the control values. At stage 24HH, glycogenolysis in glucose-free medium was 0.22, 0.17, and 0.04 nmol glucose U(h.microg protein) in atrium, ventricle, and conotruncus, respectively. Mechanical loading of the ventricle increased its oxidative capacity by 62% without altering glycogenolysis or lactate production. Blockade of glycolysis by iodoacetate suppressed lactate production but modified neither O(2) nor glycogen consumption in substrate-free medium. These findings indicate that atrium is the cardiac chamber that best utilizes its oxidative and glycogenolytic capacities and that ventricular wall stretch represents an early and major determinant of the O(2) uptake. Moreover, the fact that O(2) and glycogen consumptions were not affected by inhibition of glyceraldehyde-3-phosphate dehydrogenase provides indirect evidence for an active glycerol-phosphate shuttle in the embryonic cardiomyocytes.

Animals↗
PubMed2000

A time-domain algorithm for NMR spectral normalization.

Recently, a new method for quantitatively comparing NMR spectra of control and treated samples, in order to examine the possible occurring variations in cell metabolism and/or structure in response to numerous physical, chemical, and biological agents, was proposed. This method is based upon the utilization of the maximum superposition normalization algorithm (MaSNAl) operative in the frequency domain and based upon maximizing, by an opportune sign variable measure, the spectral region in which control and treated spectra are superimposed. Although the frequency-domain MaSNAl algorithm was very precise in normalizing spectra, it showed some limitations in relation to the signal-to-noise ratio and to the degree of diversity of the two spectra being analyzed. In particular, it can rarely be applied to spectra with a small number of visible signals not buried in the noise such as generally in vivo spectra. In this paper, a time-domain normalization algorithm is presented. Specifically, it consists in minimizing the rank of a Hankel matrix constructed with the difference of the two free induction decay signals. The algorithm, denoted MiRaNAl (minimum rank normalization algorithm), was tested by Monte Carlo simulations as well as experimentally by comparing two samples of known contents both with the new algorithms and with an older method using a standard. Finally, the algorithm was applied to real spectra of cell samples showing how it can be used to obtain qualitative and quantitative biological information.

Algorithms↗
PubMed2000

Reducing phosphine after the smoking process using an oxidative treatment.

This article gives a description of the setup in a laboratory of a pilot system to reduce phosphine following the smoking process of foodstuffs. At present, this fumigant is released into the atmosphere and causes serious damage to the environment due to its transformation into aggressive compounds. However, phosphine may prove a good alternative to methyl bromide, which will legally be used as a fumigant until the year 2002, provided it is made inert after the smoking process and transformed into nontoxic and easily disposable substances. Oxidant solutions containing potassium permanganate or potassium bichromate in suitable concentrations proved moderately effective in reducing phosphine. The addition of traces of silver nitrate as a catalyst to the oxidant solutions increased the efficiency in reducing the fumigant, although not completely. Thus it was necessary to use a recycling system to decontaminate air from phosphine, as such an apparatus ensures the complete reduction of phosphine. The mathematical function describing how the concentration of phosphine varies in the smoking chamber also makes it possible to estimate the time necessary to reduce a phosphine concentration from any initial value to a fixed final value.

Food Handling↗
PubMed2000

Nitric oxide synthase inhibition in human sperm affects sperm-oocyte fusion but not zona pellucida binding.

There is recent evidence that mouse and human spermatozoa contain constitutive nitric oxide synthase (cNOS) and can synthesize nitric oxide. The aim of this study was to investigate whether the inhibition of human sperm cNOS could affect sperm-oocyte fusion and sperm binding to the zona pellucida (ZP). N(G)-nitro-L-arginine methyl ester (L-NAME) was used as cNOS inhibitor. Sperm-oocyte fusion was evaluated using the hamster egg penetration test (HEPT). The ZP binding was evaluated using the hemizona assay. L-NAME added from the onset of capacitation strongly inhibited sperm-oocyte fusion. This inhibitory effect was dose dependent, stereospecific, and suppressed by L-arginine in a dose-dependent manner. L-NAME also inhibited sperm-oocyte fusion in the HEPT enhanced with progesterone (P), where P (5 microM) was added for 15 min to capacitated sperm. A lesser but significant inhibition was also observed when sperm suspensions were exposed to L-NAME following capacitation in both versions of HEPT. On the contrary, L-NAME did not affect ZP binding. In conclusion, the present study provides the evidence that cNOS plays a role in the human sperm's capacity to fuse with oocyte but not in the ZP binding.

Animals↗
PubMed2000

Helicobacter pylori infection and peptic disease in coeliac disease.

OBJECTIVE: To evaluate Helicobacter pylori (HP) and peptic disease prevalence in coeliac disease patients and in a control group. DESIGN: In the retrospective study, data collected on 690 upper endoscopies in coeliac patients, carried out between 1990 and 1997, were analysed. In the prospective study 263 consecutive adult patients were studied for follow-up of coeliac disease or suspected malabsorption/coeliac disease. Tests included routine blood tests; serum dosage of EMA; IgG anti-HP and, in a subgroup of participants, anti-CagA antibodies; upper endoscopy with multiple gastric and duodenal biopsies; histological examination of gastric and duodenal specimens with staining providing evidence for the presence of HP. SETTING: A centre for the treatment of malabsorptive diseases, University Federico II of Naples, Italy. PARTICIPANTS: Adults with coeliac disease at the time of diagnosis and follow-up. RESULTS: In the retrospective study, peptic disease had a prevalence of 0.72% in the endoscopy series of coeliac patients examined. In the prospective study, the prevalence of HP infection was significantly lower in untreated coeliac patients when compared with treated patients and controls (20.7%, 32.4% and 55.3%, respectively; P = 0.001, chi2). The prevalence of HP was related to both gender and age. It was found more frequently in men and the frequency increased with age in all groups. The study confirmed the low prevalence of peptic disease in coeliac patients compared with controls (0.9% vs 3.8%, P = 0.001). CONCLUSION: Patients with coeliac disease show a significantly lower prevalence of HP infection and peptic disease when compared to controls. Gluten free diet-induced changes in the intestinal environment and/or the host immuno-response may explain the increased HP prevalence in treated coeliac patients.

Adolescent↗
PubMed1999

Naturally-occurring antisperm antibodies in men: interference with fertility and implications for treatment.

Naturally-occurring antisperm antibodies in men are a relative cause of infertility, being the fertility impairment related with the degree of sperm autoimmunization. The impairment of sperm penetration through the cervical mucus represents the best established mechanism of the antibody interference with fertility. Another mechanism may involve complement-mediated sperm injury and opsonizing effect through the female genital tract. Finally, sperm-bound antibodies can interfere with sperm functions involved in the fertilization process, mainly in the sperm-zona pellucida interaction. While some mechanisms of the antibody-interference with fertility depend only on the degree of sperm autoimmunization (e.g., inhibition of cervical mucus penetration), other mechanisms (e.g., interference with gametes interaction) could or could not occur depending on the relevance in the fertilization process of the specific antigen(s) recognized by antisperm antibodies, which are policlonal in nature. Intrauterine insemination is an effective treatment when sperm autoimmunization is low or moderate, mainly if combined with corticosteroid treatment and superovulated cycles. On the contrary, its effectiveness in cases of high degree of sperm autoimmunization is controversial. The resort to "high tech" procedures is mandatory when other less invasive approaches have failed or they may also be chosen as a first-choice method in cases of high degree of sperm autoimmunization. Since in most reports the fertilization rate with in vitro fertilization and embryo transfer (IVF-ET) was significantly lower in the presence of sperm-bound antibodies than in the case of other indications, the likelihood of fertilization is higher with intracytoplasmatic sperm injection (ICSI), where the reported fertilization rates are similar to those in other indications, or even higher.

Adrenal Cortex Hormones↗
PubMed1999

Forced adhesive growth of K562 leukemic cells that normally grow in suspension induces variations in membrane lipids and energy metabolism: a proton NMR study.

The mechanisms responsible for the adhesion of cells onto a material's surface and the effects that that adhesion may have on cell structure and function are fundamental questions in biomaterials research. We recently demonstrated that the erythroleukemic cell line K562, which normally grows in suspension, can be induced to grow attached to a polylysine-coated solid surface in an anchorage-dependent manner. In this study, the effects of the growth of K562 cells onto polylysine were further investigated utilizing 500 MHz 1H-NMR spectroscopy. The NMR results showed that when K562 cells are grown attached to a positively-charged polylysine surface, there are alterations in lipids and energy metabolism. In particular, there was a 31% increase in phosphatidylcholine and a 15% decrease in each of its two precursors, glycerophosphatidylcholine and choline, as well as a 20% increase in CH2 lipids and a 7% decrease in CH3 lipids in treated cells compared to the controls. These results suggest that adhesive growth can induce strong variations in membrane structure, including the membrane fluidity of K562 cells. In addition, in cells attached to polylysine there was about a 10% decrease in creatine (together with phosphocreatine), a 20% increase in gamma-glutamate, a 15% increase in beta-glutamate, and a 24% decrease in lactate. This second set of results, which is closely related to energy metabolism, indicates that not only does adhesive growth induce changes in K562 cell membrane structure, but also in the utilization of energy in these cells. The data are discussed in view of the possible role played by surface charge in affecting cell structure and function in cells that come into direct contact with charged biopolymers.

Cell Adhesion↗
PubMed1999

A new algorithm for NMR spectral normalization.

There is increasing use of high-resolution NMR spectroscopy to examine variations in cell metabolism and/or structure in response to numerous physical, chemical, and biological agents. In these types of studies, in order to obtain relative quantitative information, a comparison between signal intensities of control samples and treated or exposed ones is often conducted. The methods thus far developed for this purpose are not directly related to the overall intrinsic properties of the samples, but rather to the addition of external substances of known concentrations or to indirect measurement of internal substances. In this paper, a new method for quantitatively comparing the spectra of cell samples is presented. It depends on a normalization algorithm which takes into consideration all cell metabolites present in the sample. In particular, the algorithm is based on maximizing, by an opportune sign variable measure, the spectral region in which the two spectra are superimposed. The algorithm was tested by Monte Carlo simulations as well as experimentally by comparing two samples of known contents with the new method and with an older method using a standard. At the end, the algorithm was applied to real spectra of cell samples to show how it could be used to obtain qualitative and quantitative biological information.

Algorithms↗
PubMed1999

Determination of the wax ester content in olive oils. Improvement in the method proposed by EEC regulation 183/93.

A simpler and faster procedure than the official one described in document IV of European Economic Community Regulation 183/93 is proposed. The wax ester fraction is isolated from triglycerides using a commercially available silica gel column and carbon tetrachloride as eluent. The recovered wax ester fraction, with the addition of a suitable internal standard solution, is analyzed by gas chromatography. A column with a 65% phenyl methyl silicone stationary phase allows a satisfying separation of wax ester fraction in comparison with both a steryl ester and a light fraction eluted before the internal standard. Furthermore, also the single components of the wax ester fraction are suitably separated.

Chromatography, Gas↗
PubMed1999

[Infectivity of Anopheles melas vis-a-vis Plasmodium falciparum in the coastal lagoon area of Benin].

In this article An. melas infestation rate for P. falciparum is compared to the rate of An. gambiae in the coastal and lagoon area of Benin where the two species are sympatric. We studied the variation of An. gambiae complex infestation rate in three zones where the two species occur in different proportions. This infestation rate is higher in areas where An. gambiae is prevalent. In a second experiment we separated An. melas and An. gambiae according to cytogenetic and biometrical analysis. Then we established the infestation rate of each species by microscope examination of salivary glands and presence of P. falciparun C.S. antigens by ELISA method. In areas where An. melas is the most abundant species (80-90%), the sporozoitic index and antigen C.S. + P. falciparum rate are significantly lower. These results are confirmed by the infestation rates observed for each species. In conclusion, An. melas infestation rate is significantly lower than the An. gambiae one. An. gambiae is the best malaria vector in Africa. In spite of an environment such as Ganvie where animals are rare, which increases anthropophilic and endophilic tendencies of An. melas, antigens CS P. falciparum rate of An. gambiae (3.5%) are significantly higher than An. melas (1.9%).

Animals↗
PubMed1999

Panic disorder in children and adolescents.

Panic disorder (PD) is a well-known and frequently described psychiatric disorder in adults, that can cause clinically significant distress and impairment of social and occupational functioning. It is characterized by a discrete period of intense fear and discomfort, that develops abruptly and reaches a peak in 10 minutes or less, with other somatic and cognitive symptoms. PD in prepubertal children and early adolescents in rarely reported, but 18% of adult patients with PD indicate onset of PA before 10 years of age. Probably many of the prepubertal cases are being misdiagnosed, and/or they can have a different clinical expression from adults. The lack of identification of these affected subjects can have serious consequences on social and academic development. The aim of this paper is to review clinical literature describing PD in children and adolescents. Prevalence, specificity of clinical features, comorbidity, instruments for diagnosis are described. Directions in pharmacological, psychotherapeutic and educational management of PD in children and adolescents are suggested.

Adolescent↗
PubMed1999

Prolonged mivacurium-induced neuromuscular block. Case report.

A 38-year-old white male patient was admitted to the hospital for elective surgery. General anesthesia was performed with propofol, alfentanil, nitrous oxide and mivacurium as neuromuscular blocker. Seven months before he had the same surgery without anesthetic problems (he received: propofol, vecuronium bromide, fentanil, nitrous oxide). Neuromuscular monitoring was carried out because the patient was included in a study assessing the clinical effect of mivacurium in microlaryngoscopy surgery. After mivacurium administration the first signs of recovery from neuromuscular block were observed after 255 min. The tracheal tube was withdrawn after 410 min from mivacurium administration, at this time the T1 was 80% of the control values and 7 min later the T1 reached 98%.

Adult↗
PubMed1998

A prospective analysis of the accuracy of the TEST-yolk buffer enhanced hamster egg penetration test and acrosin activity in discriminating fertile from infertile males.

The aim of this study, based on a prospective analysis, was to evaluate the accuracy of the TEST-yolk buffer enhanced hamster egg penetration test (HEPT) and acrosin activity in discriminating fertile from infertile males as compared with the conventional semen profile. The incidence of spontaneous pregnancies was monitored during a follow-up period ranging between 18-24 months in 62 couples without untreatable female infertility. The diagnostic accuracy of the HEPT was significantly higher than that of the conventional semen profile, as evaluated with fitted ROC curves. The best discriminatory ability was exhibited by a penetration index (penetrations/oocyte) of 2 as cut-off value. In our series it gave a positive predictive value of 77.8% and a negative predictive value of 92.3%. Acrosin activity did not show a discriminating power significantly higher than the conventional semen profile, but an acrosin activity <20 microIU/10(6) spermatozoa was found only among patients who did not achieve a pregnancy. In conclusion, this prospective analysis indicates that the TEST-yolk buffer enhanced HEPT constitutes a significant improvement over the conventional semen profile in discriminating fertile from infertile males. Acrosin activity could provide a useful adjunctive test because of the high negative predictive value of its poor results.

Acrosin↗
PubMed1998

Carbohydrate binding activity in human spermatozoa: localization, specificity, and involvement in sperm-egg fusion.

Sperm carbohydrate binding activity is involved in gamete recognition. We identified a human sperm protein extracted under reducing conditions, and with a molecular mass of 65 kDa on sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), and which binds D-mannose coupled to albumin (DMA) in presence of cations and a neutral pH. Epifluorescence microscopy showed that fluorescein-DMA binds to dead or permeabilized sperm heads. The DMA-binding activity of human sperm heads was highly specific for a polysaccharide structure containing charged sugar residues. After capacitation, or induction of the acrosome reaction using solubilized zonae pellucidae, fluorescein-DMA was bound respectively to 10.3% (+/- 3.5%) and to 37.6% (+/- 2.1%) of viable sperm heads. The sequential analysis of viable spermatozoa for fluorescein-DMA binding and for rhodamine-Pisum sativum agglutinin binding, showed that DMA-binding sites are present in viable acrosome-reacted spermatozoa. Three dimensional analysis of fluorescence and ultrastructural studies showed that DMA-binding sites are mostly restricted to the sub-acrosomal space of the equatorial segment. Incubation of spermatozoa and zona-free hamster eggs in the presence of DMA was associated with a dose-dependent significant reduction in the number of spermatozoa bound to the oolemma, compared with a control, and to a dose-dependent inhibition of oocyte penetration. This effect was highly specific for DMA, suggesting that DMA-binding sites in human spermatozoa are involved in sperm-egg fusion.

Adult↗