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Biomedical subjects

R Romano

Publications and source records attributed to R Romano.

At least 19 recordsLinked to original sources
PubMed2005

A 700 MHz 1H-NMR study reveals apoptosis-like behavior in human K562 erythroleukemic cells exposed to a 50 Hz sinusoidal magnetic field.

PURPOSE: To study cell damage and possible apoptosis in K562 human erythroleukemic cells exposed for 2 h to an extremely low frequency (ELF) 50 Hz sinusoidal magnetic field with a magnetic induction of either 1 or 5 mT using high resolution proton nuclear magnetic resonance (1H-NMR) spectroscopy. MATERIALS AND METHODS: One-dimensional 1H-NMR spectra were obtained on whole K562 cells and perchloric acid extracts of these cells. In addition, two-dimensional 1H-NMR spectra were also acquired. Cell damage was examined by lactate dehydrogenase release and changes in cell growth were monitored by growth curve analyses, bromodeoxyuridine incorporation and Ki67 antigen localization. Cell death (necrosis and apoptosis) were also studied by using the chromatin dye Hoechst 33258. RESULTS: The variations in numerous metabolites observed with 1H-NMR reveal apoptosis-like behavior in response of K562 cells to ELF fields. CONCLUSION: 1H-NMR can be extremely useful in studying the effects of ELF fields on cells. In particular, the variations in metabolites which suggest apoptosis-like behavior occur when the cells are not identifiable as apoptotic by more traditional techniques.

Apoptosis↗
PubMed2003

Evaluation of the effect of 17alphaOH-progesterone and 17beta-oestradiol on human sperm ability to fuse with oocytes: comparison and possible interference with the effect of progesterone.

The demonstration of a stimulatory effect of progesterone (P) on the sperm/oocyte fusion has provided the most relevant biological evidence of the effect of P on sperm functions involved in fertilization. Some evidence exists that 17alpha-hydroxyprogesterone (17alphaOH-P) and 17beta-oestradiol (17beta-E2), could also exert non-genomic effects on human spermatozoa and a role for 17beta-E2 as a possible physiological modulator of P action on spermatozoa has been suggested. This study aimed to determine the effect of the exposure of human spermatozoa to 17alphaOH-P and 17beta-E2 on sperm/oocyte fusion as well as the possible interference of 17beta-E2 with the effect of P. The effect of steroids on sperm/oocyte fusion was assessed by means of the hamster egg penetration test (HEPT). The exposure of capacitated sperm suspensions to scalar doses of 17alphaOH-P produced a significant enhancement of penetrations/oocytes with a dose/response effect. It was equal to 75.3% of that produced by equimolar doses of P. Conversely, 17beta-E2 (from 100 nM to 50 microM) did not produce any significant effect when added either before or after capacitation. Moreover, the sperm pre-incubation with 17beta-E2 did not interfere with the stimulatory effect of P. These results support a physiological role for 17OH-P in the process of fertilization, but not a role for 17beta-E2 as a possible physiological modulator of P action on spermatozoa.

17-alpha-Hydroxyprogesterone↗
PubMed2003

Effects of remifentanil on human heart electrical system. A transesophageal pacing electrophysiological study.

AIM: Previous studies have shown that the administration of remifentanil (a micro-agonist opioid) is often accompanied by bradyarrhythmias preventable or manageable by parasympatholytic drugs. The aim of this paper is to evaluate if these negative chronotropic effects are exclusively due to an increased parasympathetic activity or to a direct action of remifentanil on heart conduction fibres. METHODS: A transesophageal pacing electrophysiological study on 40 healthy subjects scheduled for orthopaedic surgical treatment under general anaesthesia has been carried out. We determined either the correct sinus recovery time or the occurrence of Wencke-bach atrio-ventricular block in the awake state and, again, during remifentanil administration. RESULTS: In all patients either a significant depression of sino-atrial automatism or a decrease of atrio-ventricular node conduction reserve was noticed. In 2 cases, in particular, a sinus arrest and a junctional rhythm, respectively, both spontaneously recovered were observed. CONCLUSION. Atropine normalized all parameters, confirming that remifentanil-associated hypokinetic cardiac phenomena are exclusively vagally mediated.

Adult↗
PubMed2002

Effect of human sperm exposure to progesterone on sperm-oocyte fusion and sperm-zona pellucida binding under various experimental conditions.

In this study, the effect of human sperm exposure to progesterone on sperm/oocyte fusion, using the hamster egg penetration test, and on sperm/zona pellucida (ZP) binding, using the hemizona assay, was investigated under various experimental conditions. A brief exposure of human spermatozoa to progesterone exerted a stimulatory effect on sperm/oocyte fusion which was dose-dependent, capacitation-dependent, influenced by the source of serum albumin in capacitating medium, and was higher than that produced by the exposure to progesterone from the onset of capacitation. The exposure of capacitated spermatozoa to progesterone during 20 min-spermatozoa/ZP-coincubation produced an enhancement of ZP-binding, which was not significantly influenced by the source of serum albumin in capacitating medium. A significantly lower ZP-binding was exhibited by spermatozoa exposed to progesterone from the beginning of capacitation. These results indicate that progesterone exerts a stimulatory effect on human sperm's fertilizing ability, which occurs mainly in post-capacitation events directly involved in sperm/oocyte fusion and in ZP-binding. Conditions optimizing these effects are provided. They should be taken into account in the standardization of experimental and clinical studies designed to evaluate the response of human spermatozoa to progesterone.

Animals↗
PubMed2002

Interactive effect of semen and cervical mucus quality on postcoital test outcome: analysis from an andrological point of view.

This study analysed the relationship between semen quality and the postcoital test (PCT) outcome in 616 couples, especially focusing on the interactive effect of semen and cervical mucus quality. When PCTs performed in the presence of unfavourable mucus were excluded, a significant correlation was found between semen parameters and PCT outcome. In oligo/asthenozoospermia, 46.7% of PCT outcomes were negative, while the remaining were positive. Notably, in the presence of an optimal mucus score, 39% of PCT outcomes were good (> or = 7 forward motile spermatozoa/high power field). In normozoospermia, 16% of PCT were negative. A suboptimal cervical mucus quality significantly affected the PCT outcome in the presence of oligo/asthenozoospermia, but not in normozoospermia. In couples with repeated PCT, a better mucus score was associated with a significant improvement of the PCT outcome. When the outcome of two PCTs performed in the same couples with an unmodified mucus score was compared, a good consistency of the results was observed. In conclusion, the PCT can provide information in additional to that obtained from conventional semen analysis, as the interactive effect of semen/cervical mucus cannot be accurately inferred from the separate evaluation of the two members of a couple.

Cervix Mucus↗
PubMed2002

Transesophageal atrial pacing in the management of re-entry supraventricular tachyarrhythmias occurring during general anesthesia.

BACKGROUND: Supraventricular tachyarrhythmias (SVTs) represent an intraoperative risk factor that should be always prevented/managed. The commonly used anti-arrhythmic drugs are accompanied by intrinsic hazards, such as pro-arrhythmic and toxic effects or unpredictable onset and duration of action. We underline the therapeutic use of transesophageal atrial pacing (TAP) for the interruption of particular re-entry SVTs occurred during surgical procedures in general anaesthesia. METHODS: Our study was carried out in 25 patients characterized by a personal clinical history of transient tachyarrhythmic episodes, subjected to general anaesthesia obtained by midazolam, propofol, N2O e O2, sevoflurane, fentanil and vecuronium bromide. We used TAP bursts of 3-5 sec, their minimal pacing rate being equivalent to the tachyarrhythmia cycle length, with an impulse intensity ranging from 18 to 25 mA. In such conditions, the re-entry was interrupted by the induction of refractoriness of the wave-front that sustained the underlying arrhythmogenic circuit. RESULTS: During the study, the following arrhythmias occurred in 7 out of all patients: 1 type I atrial flutter, 3 nodal tachycardias, 1 antidromic and 2 orthodromic atrioventricular tachycardias, respectively. TAP assured either atrial capture or prompt suppression of arrhythmias in all cases. Low intensity impulses did not ever allow ventricular capture. CONCLUSIONS: TAP can be considered as a valid therapeutic device for the management of re-entry SVTs occurred during general anaesthesia, resulting it effective, safe and easy-practicable.

Anesthesia, General↗
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

Increased risk of surgery in undiagnosed celiac disease.

The diagnosis of celiac disease patients may be delayed by misdiagnosis. Our aim was to evaluate in celiac patients the prevalence of surgery before diagnosis. Two hundred forty-four adult celiac patients and 232 controls were retrospectively investigated for surgery before diagnosis of celiac disease. The prevalence of surgery was increased in celiac patients versus controls (P = 0.001). Frequency of appendectomy (P = 0.0001), tonsillectomy (P = 0.009), and hernia repair (P = 0.05) were increased in celiac patients versus controls. Appendectomy was related to anemia (P = 0.006) and abdominal pain (P = 0.005); tonsillectomy was related to diarrhea (P = 0.02) and weight loss (P = 0,04). Appendectomy was elective in 73% of celiac patients and in 46% of controls. Cosmetic surgery was increased in celiac patients versus controls (P = 0.058). In conclusions, surgery before celiac disease diagnosis is increased in celiac patients compared to controls, as a result of doctors' misdiagnosis and/or poor health status, which increases the demand for medical intervention. The frequency of cosmetic surgery in celiac patients may berelated to impaired psychological profile of patients.

Adult↗
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↗
PubMed2001

Ambulatory anesthesia for foot surgery.

Ambulatory surgery has developed extensively over the past few years in most Western countries. The absence of specific legislation in Italy creates a lack of trust in patients and interferes with the development of this discipline. The authors describe their experience in the organisation of an outpatient foot surgery centre over the past thirteen years, which is in constant expansion and currently performs about 300 operations every year. They report the criteria used to select patients, the organisation of the operating theatre, pre- and postoperative treatment and the anesthetic techniques used. Among the latter, they describe a new approach used to block the popliteal sciatic nerve. The results obtained show a high approval rate from the majority of patients treated. The authors attribute this success to a series of factors, including patient selection and surgical procedures, the maintenance of constant standards of quality similar to those in hospitals and the experience of outpatient anesthesia.

Ambulatory Surgical Procedures↗
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↗