Physiological characterization of supramedullary/dorsal neurons of the cunner, Tautogolabrus adspersus.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to M Motta.
Explore the source record for details and available documents.
The authors report a case of a salivary duct carcinoma (SDC) of the parotid gland revealed by a facial palsy. The clinical and pathological features of this highly malignant neoplasm are described. The aggressive nature of this form demands a combined chemo-radio-surgical treatment; only early recognition and treatment are likely to result in a favourable outcome.
Explore the source record for details and available documents.
The bioequivalence of two different formulations containing roxithromycin (SPE-712-1). Oral suspension 300 mg/15 mL as test formulation and Rotram, tablets 300 mg as reference formulation, both by Schering Plough S.A., Brazil) was evaluated in 24 healthy volunteers of both sexes (12 male and 12 female). The study was conducted open with randomized two-period crossover design and a 14-day washout period. Each subject received 300 mg of each roxithromycin formulation. Plasma samples were obtained over a 72-hour interval and roxithromycin concentrations were analyzed by combined LC-MS/MS with positive ion electrospray ionization using selected ion monitoring method. From the plasma roxithromycin concentration vs time curves the following pharmacokinetic parameters were obtained: AUC(0-72 h), AUC(0-infinity), Cmax, t1/2 ratios and tmax individual differences. The 90% for confidence interval (CI) of geometric mean SPE-712-L/Rotram individual percent ratio were 105.0-128.3% for AUC(0-72 h), and 78.4-96.9 for Cmax. Although this 90% CI were marginally outside the interval proposed by the Food and Drug Administration, the probability assessed by the two-one sided West for ratios was included in the 0.8-1.25 interval, as we concluded that SPE-712-L oral suspension formulation was bioequivalent to Rotram tablet formulation for the extent and rate of absorption.
Hereditary spherocytosis is the most common red blood cell membrane disorder and often is associated with hemolytic crisis and premature cholelithiasis. Splenectomy is the only effective therapy for this disorder and often it is performed in combination with cholecystectomy. Conventional surgery requires a wide upper abdominal incision for correct exposure of the gallbladder and spleen. Laparoscopic cholecystectomy and splenectomy have been performed safely worldwide. We report our experience with seven patients (one male and six female, average age 12 years) who underwent combined laparoscopic splenectomy and cholecystectomy for hereditary spherocytosis. The patient was placed in supine position and the procedure performed with a five-trocar technique. Cholecystectomy was performed first, then splenectomy was achieved and the spleen removed by morcellation into a retrieval bag (five cases) or via a 4- to 5-cm left subcostal incision (two cases). No patient required conversion to open technique or blood transfusion. The mean blood loss was 162 mL, mean operative time 207 minutes, mean spleen size 14.5 cm, and median postoperative hospital stay 4 days. No perioperative mortality or major complications occurred in our series. After a median follow-up of 18 months all patients showed sharp hematologic improvement. Despite the small number of cases, we consider the combined laparoscopic approach safe and effective for the treatment of hereditary spherocytosis.
Neuropeptide Y (NPY) participates in the control of several functions in the nervous system. NPYergic neurons present in brain areas involved in cognitive processes are linked to ascending projections of the cholinergic system, a finding that suggests a role for acetylcholine in the control of these cells. In the present study, the effect of the activation of cholinergic muscarinic receptors on the expression of the human NPY gene was assessed. The SH-SY5Y neuroblastoma cell line was used as an in vitro model of human neurons; NPY mRNA levels were evaluated by Northern blot analysis. The results indicate that: (a) the expression of the human NPY gene in SH-SY5Y cells is stimulated by the cholinergic muscarinic agonist, carbachol; (b) this effect is mediated by the M3 muscarinic receptor subtype, as indicated by the inhibitory effect of the M3 antagonist 4-DAMP; (c) protein kinase C (PKC) activation plays an important role in the induction of NPY gene expression in this system, as suggested by experiments with the PKC activator, TPA, and the PKC inhibitor, GF 109203X; (d) the stimulation of NPY mRNA levels by TPA and by carbachol in SH-SY5Y cells requires de novo synthesis of RNA and protein. In conclusion, the present study shows that the activation of PKC-coupled muscarinic receptors as the M3 subtype positively modulates the expression of the human NPY gene in SH-SY5Y neuroblastoma cells, via PKC-related mechanisms.
Experiments have been performed to clarify whether LHRH agonists might decrease growth of hormone-unresponsive prostate cancer in vivo. Male nude mice were injected s.c. with the human androgen-independent prostate tumor DU 145 cells; osmotic minipumps releasing the LHRH agonist Zoladex (LHRH-A) for 14 days were simultaneously implanted under the skin. Treatment with LHRH-A induced a significant decrease in tumor growth up to the end of the treatment. In subsequent experiment, minipumps releasing LHRH-A were implanted in nude mice either 7 or 14 days after cell inoculation. When the treatment was started 7 days after inoculation of the cells, tumor growth was significantly decreased up to 28 days; thereafter, tumor volume remained lower than in controls, although not significantly. When LHRH-A was administered beginning 14 days after cell inoculation, tumor growth was not significantly affected at any time interval considered. LHRH-A did not appear to induce apoptosis in DU 145 cells, at least on the basis of the apoptotic index and immunohistochemical staining of the p53 protein. On the other hand, treatment with LHRH-A was accompanied by a significant decrease of the concentration of epidermal growth factor receptors in DU 145 prostate cancer specimens. Our results show that the LHRH agonist used significantly inhibits the growth of DU 145 androgen-independent prostate tumor xenografts in nude mice.
BACKGROUND: Prostate trophism depends on DHT formed from T by the enzyme 5alpha-R. Two 5alpha-R isoforms with different biochemical characteristics have been cloned. Also estrogens might contribute to the prostate growth; however, their intraglandular formation by the enzyme aromatase is still debated. The aim of the present study was to verify whether (a) only one or both isoforms of the 5alpha-Rs are expressed in the prostate cancer cell line LNCaP and in BPH, or (b) the aromatase is present in these samples. METHODS: The profile of the pH optimum of the 5alpha-Rs was evaluated "in vitro" in LNCaP cells by the production of labeled 5alpha-reduced metabolites either from [14C]-T or [14C]-D4 at pH 3.5-8. The gene expression of the two 5alpha-Rs and of the aromatase in LNCaP cells and in BPH specimens was analyzed by RT-PCR combined to Southern blot analysis, using specific sets of oligonucleotides. The tissue localization of 5alpha-R1 was analyzed by immunohistochemistry using an anti-5alpha-R1 polyclonal antibody. RESULTS: (a) In LNCaP cells, the formation of 5alpha-reduced metabolites from the respective precursors increases progressively as a function of pH, being the highest at neutral pH values; (b) the 5alpha-R1 isoform is expressed in both LNCaP cells and in BPH, while the 5alpha-R2 mRNA is present only in BPH, but not in LNCaP cells; and (c) no aromatase transcripts were observed either in BPH or in LNCaP cells. CONCLUSIONS: A careful examination of the possible differential expression of T-activating enzymes, particularly in prostate cancer, would be of help to choose the appropriate treatment.
Explore the source record for details and available documents.
The present paper will summarize two important aspects of the interactions between steroids and the brain, which have recently been studied in the authors' laboratory. In particular the paper will consider data on: (1) the significance of the two isoforms of the 5alpha-R during brain ontogenesis and development, and (2) the cross-talk between glial and neuronal elements, particularly in relation to the metabolism of sex hormones. (1) The data obtained have shown that the 5alpha-R type 1 enzyme is constitutively expressed in the rat CNS at all stages of brain development. Moreover, the expression of the 5alpha-R type 1 is similar in males and in females, and does not appear to be controlled by androgens. The gene expression of the 5alpha-R type 2 is totally different. This isoform appears to be expressed in the rat brain almost exclusively in the late fetal/early post-natal life and is controlled by testosterone. (2) The present data show that two cell lines derived respectively from a rat glioma (C6 cell line) and from a human astrocytoma (1321N1 cell line) are able to convert testosterone and progesterone into their corresponding 5alpha-reduced metabolites dihydrotestosterone and dihydroprogesterone. The possibility that secretory products of normal and tumoral brain cells might be able to influence steroid metabolism occurring in the two glial cell lines previously mentioned has been considered.
Quality of life and behavioral functions are severely reduced in patients affected by Alzheimer's disease (AD). Among the drugs employed in the treatment of this invalidating degenerative dementia, tacrine (THA) seemed to play a possible therapeutic role. Our study was aimed to evaluate the efficacy of THA in the treatment of AD, performing a comparison with lecithin and/or placebo treatment. Five randomized controlled trials on tacrine versus lecithin and/or placebo treatment were randomly selected. Mantel-Haenszel-Peto method was applied. Patients treated with tacrine achieved better results than control subjects (overall OR = 2.34; 95% CI 1.42-3.85); but long-term treatment with tacrine was not significantly more efficacious than placebo. Statistical significance in favor of THA versus other drugs employed was obtained in MMSE and ADAS-Cog tests in the studies carried out by Eagger et al. and Knapp et al. Moreover, Fitten et al. administered the highest tolerated THA dose to only a few patients enrolled in the study. The presence of broad CIs observed in the 5 meta-analytic studies infer non homogeneity of effects of treatment. Solely few patients improved, whereas the clinical conditions of the majority remained stationary. Between 5 and 10% of the outpatients in each single study presented reversible side effects calling for suspension of THA treatment. The optimal dose ranged between 80 and 160 mg THA, but often produced side effects. Comparative trials revealed the reduced efficacy and elevated toxicity of THA treatment, dampening the initial enthusiasm concerning the usefulness of this drug in AD. Furtermore, tacrine-induced side effects provoked many dropouts in all studies investigated. The effectiveness of tacrine treatment in AD disease was not fully confirmed. Other studies are required to identify doses and modalities of administration of this drug in AD.
The present article shows for the first time that two cell lines derived respectively from a rat glioma (C6 cell line) and from a human astrocytoma (1321N1 cell line) are able to convert testosterone and progesterone into their corresponding 5 alpha-reduced metabolites dihydrotestosterone and dihydroprogesterone. Moreover, both cell lines are also able to convert these metabolites further into their corresponding 3 alpha-OH derivatives, 5 alpha-androstan-3 alpha, 7 beta-diol (3 alpha-diol) and tetrahydroprogesterone. On the basis of these observations, the possibility that secretory products of normal and tumoral brain cells might be able to influence steroid metabolism occurring in the two glial cell lines previously mentioned as well as in fetal rat neurons and in neonatal rat type 1 astrocytes has been considered. To this purpose, cultures of the different cellular types have been exposed to the conditioned medium in which the other cells were grown. The results obtained indicate that: 1. Neurons are able to stimulate, in a statistically significant fashion, the formation of dihydrotestosterone (DHT), 3 alpha-diol, and tetrahydraprogesterone (THP) in C6 cells. 2. Type 1 astrocytes, on the contrary, are unable to modify steroid metabolism in C6 cells. 3. C6 cell product(s) decrease(s) the formation of DHP in type 1 astrocytes, without modifying that of DHT. 4. C6 cells do not influence the metabolism of testosterone (T) and progesterone (P) in neurons. In conclusion, the present observations show that the conditioned medium of normal neurons is able to increase the metabolism of testosterone and progesterone occurring in a tumoral glial cell line, and that the conditioned media of the two tumoral cell lines analyzed are able to decrease the conversion of P into DHP occurring in normal type 1 astrocytes. The surprising result that these conditioned media do not alter the formation of DHT is discussed. Work is presently in progress to identify the principle(s) responsible respectively for the activating and inhibiting actions here described.
BACKGROUND AND OBJECTIVE: Thrombopoietin has been established as the major regulator of megakaryocyte and platelet production. In this study we evaluated the effects of PEG-recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF), a pegylated and truncated form of thrombopoietin, on the growth and differentiation of the HEL cell line. As a model system we chose the pluripotent HEL line that acquires multiple markers of the megakaryocyte/platelet phenotype following treatment with phorbol esters, and, more importantly, expresses the receptor for thrombopoietin (Mpl receptor) at its cellular surface. DESIGN AND METHODS: The effect of PEG-rHuMGDF on HEL proliferation/differentiation was evaluated in a liquid culture assay. RESULTS: Peg-rHuMGDF do not increase the proliferative capacity of HEL cell but, in parallel experiments, HEL cells showed a more mature and differentiated pattern after exposure to the cytokine. Our results show that PEG-rHuMGDF, at the optimal doses of 100-150 ng/mL, is able to induce: 1) morphological changes with the formation of cytoplasmic protrusions; 2) increased ploidy as demonstrated by cytofluorimetric analysis; 3) increased expression of megakaryocyte markers, including glycoprotein IIb-IIIa and the platelet-specific alloantigen (PIA1). INTERPRETATION AND CONCLUSIONS: These findings show that HEL cells represent a useful model to investigate the differentiative properties of thrombopoietin in the megakaryocyte compartment.
In the present study, the possible direct effects of opioids on the release of LHRH have been studied utilizing the GT1-1 cell model. It has been shown that only opioid agonists which bind to delta receptors bring about a significant inhibition of the release of LHRH, when this is stimulated by forskolin- or PGE2. The effects of delta opioid agonists are dose-dependent, and are reversed by the delta specific antagonist naltrindole. If one assumes that the GT1-1 cells represent a good model for the study of LHRH-secreting neurons, the obvious conclusion from these data is that endogenous opioid peptides may influence LHRH secretion also by acting directly on LHRH-secreting neurons. In another study it has been shown that GT1-1 cells possess high affinity-low capacity binding sites for estradiol and androgens. Moreover, a two-fold induction of androgen-binding sites has been observed after treatment of GT1-1 cells with estradiol, indicating that estrogen receptors are functional. The present observations suggest that gonadal steroids might influence LHRH release acting directly on the cells which manufacture and release the hypothalamic hormone. In order to evaluate the possible existence of a humoral communication between glial cells and LHRH-secreting neurons, two different approaches have been used: (a) GT1-1 cells were co-incubated with purified cultures of type 1 astrocytes; (b) GT1-1 cells were exposed to the conditioned medium (CM, untreated or submitted to different experimental procedures) where type 1 astrocytes were grown for 24 h. In both sets of experiments LHRH was measured by RIA in the incubation media of GT1-1 cells. The data show that short periods of either co-culture or exposure to previously frozen or heated CM significantly increase the release of LHRH from the GT1-1 cells. The stimulatory effect on LHRH release appears to be specific for type 1 astrocytes. Surprisingly, fresh CM proved to be inactive; this suggested that the factor(s) involved needed to be 'activated'. Since it is known that TGF beta may be liberated from its supporting proteins by freezing or heating, the effects of TGF beta and of a TGF beta-neutralizing antibody were analyzed. The stimulatory effect exerted by the frozen CM was completely abolished by the antibody, while TGF beta 1 proved able to significantly increase LHRH release from GT1-1 cells. The present data unequivocally show that type 1 astrocytes in culture release some principle(s), probably TGF beta, able to stimulate LHRH release from the LHRH-producing GT1-1 cell line. To the authors' knowledge, the present data provide the first clear-cut demonstration that the glia may directly intervene in the control of LHRH release via the secretion of humoral factors.
We have recently reported a series of 15 non-villous splenic marginal zone lymphoma patients, six of whom showed p53 mutations (40%). This molecular alteration did not correlate with any particular clinico-pathologic feature at diagnosis. After a median follow-up of 56 months, four cases evolved into aggressive fatal non-Hodgkin's lymphoma (NHL) and two had refractory progressive disease; interestingly, p53 mutations were demonstrated in five of these patients at diagnosis. As the patients with wild-type p53 presented responsive or indolent disease, this genetic alteration may be an early marker of aggressive transformation or refractoriness. p53 evaluation at diagnosis could be advisable in this particular subset of NHL.
The renal pathologic features of 120 consecutively autopsied patients affected by acquired immunodeficiency syndrome was investigated by light microscopic analysis. Variously associated renal changes were found in 82 patients (68.3%). Glomerular changes were present in 25. The following diagnoses were made: mesangial glomerulonephritis (16 patients), defined by the presence of deposits in the mesangium and/or mesangial cell proliferation; membranous glomerulonephritis (4 patients), cirrhotic glomerulosclerosis (2 patients); and lupuslike glomerulonephritis (3 patients). Glomerular diseases seemed to be significantly associated with chronic hepatitis or liver cirrhosis. Interstitial inflammation was present in 19 cases: chronic pyelonephritis (2 patients), focal nephritis (5 patients), multiple cortical abscesses (7 patients), granulomatous nephritis (5 patients). Cryptococci were found in one and undetermined microorganisms in two cases of multiple cortical abscesses. Atypical mycobacteria were found in two cases of granulomatous nephritis. Mycotic infections were identified in another 6 patients, in whom they did not elicit any inflammatory response. It is worth stressing that, although various generalized infections are common in patients with acquired immunodeficiency syndrome, only cryptococci and atypical mycobacteria also frequently involve the kidney. Focal tubular necrosis was observed in 15 patients. Benign nephrosclerosis was the most common vascular change (27 patients). Changes recalling hemolyticuremic and localized intravascular coagulation were found in three and six patients, respectively. Our data, dealing with a European Caucasian population, considerably differ from those reported in North American literature, in as much as we found no cases of human immunodeficiency virus nephropathy. Conversely, immune-mediated glomerular diseases were frequent, in agreement with recent studies on renal biopsy specimens from AIDS patients with acquired immunodeficiency syndrome. This type of infections, supplies multiple sources of antigens that may stimulate immune complex formation and, therefore, glomerular diseases.
This study evaluated paroxetine as a possible treatment for premature ejaculation. Sixty two patients affected by primary premature ejaculation were randomly assigned to two groups. A and B, and treated with two different treatment schedules. Patients assigned to group A were treated with paroxetine 20 mg p.o. daily for six months; patients assigned to group B were treated with paroxetine 20 mg p.o. daily for fourteen days, and than dose was reduced to 10 mg for a total treatment period of six months. Only one patient reported significative side effects (weakness). Positive clinical results were obtained, at the end of the treatment, in 89 per cent of group A and 88 per cent of group B. In patients with primary premature ejaculation, paroxetine represents, in our opinion, the best therapeutic option for its efficacy and lack of significant side effects.
In this work the authors make a description of the rare testis tumors. They underline the several histologic features and the difficulty of early diagnosis due to the absence of reliable markers, and as for the malignancies the unclear role of the radio and chemotherapy. The difference in terms of classification and of lack in the therapeutic standards is clear if compared with the germ cell tumors. These pathologies require an early surgical approach by using the available diagnostic imaging tools and bioptic examination.