Testosterone regulates PDE5 expression and in vivo responsiveness to tadalafil in rat corpus cavernosum

OBJECTIVES: To investigate the effect of testosterone on PDE5 expression and PDE5 inhibitor tadalafil in vivo responsiveness in a rat model. METHODS: PDE5 expression was localized by immunohistochemistry in the rat corpus cavernosum (CC) and quantified by both real-time RT-PCR and Western blot analysis in several tissues. In the in vivo study, control, castrated and testosterone (T) supplemented castrated rats were treated with acute or chronic oral tadalafil. Erectile function was evaluated by monitoring intracavernous pressure (ICP) following electro-stimulation (ES) of the cavernous nerve and intracavernous injection of NO donor, sodium nitroprusside (SNP). RESULTS: Rat CC expressed the highest PDE5 mRNA level. PDE5 was specifically immunolocalized in endothelial and smooth muscle cells. Surgical castration induced a significant reduction of PDE5 gene and protein expression (p<0.05), and ES response at all stimulation frequencies (p<0.001). T supplementation completely restored PDE5 expression, erectile response to ES and responsiveness to PDE5 inhibitor. Both acute and chronic tadalafil treatment were ineffective in ameliorating the ES response in castrated rats. Injection of increasing concentrations of SNP in castrated rats resulted in a statistically significant increase in ICP/MAP ratio as that observed in intact rats. In addition, tadalafil did not amplify the SNP effect in castrated rats at all the doses tested (0.06-6 nmoles). CONCLUSIONS: Our findings demonstrate that testosterone positively regulates PDE5 expression and in vivo responsiveness to PDE5 inhibitor, tadalafil, in the rat CC.     

Subcutaneous emphysema during intraligamental anesthesia

Periodontal ligament anaesthesia (PDLA) is a good choice to most common local anaesthesia methods. In the present work the Authors report a case of subcutaneous emphysema as adverse effect of this injection technique.     

Luxation of anterior deciduous teeth. Clinical considerations

Deciduous anterior teeth dislocations are a very high incidence pathology in children. In this work the Authors describe some cases, their complications and therapy.     

P53, bcl-2 and Ki-67 expression in adenoid cystic carcinoma of the palate. A clinico-pathologic study of 21 cases with long-term follow-up

Adenoid cystic carcinoma (ACC) is an indolent tumor that pursues a protracted clinical course with recurrences and late metastases. The aim of this study was to investigate immunohistochemically the expression of p53, bcl-2 protein, and Ki-67 in 21 cases of ACC of the palate, all with a minimum of 10 years and a maximum of 22 years of clinical follow-up. These results were also analyzed with regard to different clinical prognoses of the histologic subtypes of ACC. High expression of p53 and bcl-2 was noted in 19 out of 21 ACC cases (90%), in which most tumor cells (from 66% to 99%) proved to be immunopositive. A relation to the histologic types, clinical staging, and survival was not found. Therefore, the high immunoreactivity against these oncoproteins in the same tumor cells suggests that these two oncogenes may be involved since the early stage of carcinogenesis. Loss of function of the p53 protein combined with bcl-2 upregulation might give the tumor cells a double growth advantage, because uncontrolled proliferation is combined with a reduced cell death rate. The interaction with other oncogenes may then trigger a multistep process able to promote tumor progression. The low labeling index Ki-67 was detected in nine out of 21 cases (42%), with a low percentage of tumor cells (from 3% to 15%) being positive, whereas the remaining 12 cases were negative. We found no relation to the histologic types, clinical staging, and survival; however, the low proliferation rate could explain the natural course of tumor.     

VEGF expression in the placenta from pregnancies complicated by hypertensive disorders

OBJECTIVE: To determine the expression of VEGF in the placental tissue from pregnancies complicated by hypertension disorders of different clinical severity. DESIGN: Prospective cohort study. SETTING: Polyclinic of Careggi, University of Florence, Italy. SAMPLE: Placentas from women with gestational hypertension (n= 20), pre-eclampsia (n= 20) and pre-eclampsia with HELLP syndrome (n= 20) and from normotensive women (n= 20), as control group (gestational age comprised between 35 and 38 weeks). METHODS: An immunohistochemical technique and a quantitative analysis to measure mRNA levels (RT-PCR) were employed. MAIN OUTCOME MEASURES: Intensity of immunoreactivity and mRNA levels in the placental components. Differences between the data. RESULTS: VEGF immunoreactivity was observable in all the placental components in the gestational hypertension cases as in the control ones. In the cases with pre-eclampsia and pre-eclampsia with HELLP syndrome, some placental components were not immunoreactive. However, the VEGF positive components of all the pathological groups showed a higher intensity of reactivity with respect to that of the control group. The levels of VEGF mRNA were higher in the gestational hypertension cases and lower in the cases of pre-eclampsia with HELLP syndrome with respect to the control ones; in the cases of pre-eclampsia, the levels were the same as the control ones. CONCLUSION: The different expression of VEGF in the placenta of the pathological cases is probably related to haemodynamic changes that take place in these disorders, in order to attempt restoration of a normal uteroplacental flow.     

Oxytocin receptor is expressed in the penis and mediates an estrogen-dependent smooth muscle contractility

Oxytocin (OT) is released by the posterior pituitary during male orgasm and is supposed to participate in the ejaculatory process. We now report evidence demonstrating the presence of an OT receptor gene (real-time RT-PCR and Northern blot) and protein (immunohistochemistry, Western blot, and binding studies) expression in the rabbit and human corpus cavernosum (CC) and its possible involvement in postorgasmic penile detumescence. OT receptor is expressed in the penis at a concentration similar to that present in other portions of the male genital tract and mediates CC contractility. OT-induced CC contractility is clearly regulated by the changing sex steroid milieu. In fact, we found that in a rabbit model of hypogonadotropic hypogonadism (induced by a single administration of the long-acting GnRH agonist triptorelin pamoate, 2.9 mg/kg), OT responsiveness was strongly reduced and was completely restored by estradiol valerate (3.3 mg/kg weekly), but not by testosterone enanthate (30 mg/kg weekly). As we found that CC expresses both subtypes of estrogen receptors and P450 aromatase, we hypothesized a physiological role for endogenous estrogens in regulating OT responsiveness. We therefore treated adult rabbits with an aromatase inhibitor (letrozole, 2.5 mg/kg) or an antiestrogen (tamoxifen, 0.25 mg/kg) for 3 wk. Both treatments significantly reduced CC responsiveness to OT stimulation. In conclusion, these findings indicate that OT might participate in inducing postorgasmic penile flaccidity and suggest a new role for estrogens in the male: regulation of CC responsiveness to OT.     

Increased levels of IGF-1 and beta2-microglobulin in epithelial lining fluid of preterm newborns developing chronic lung disease. effects of rhG-CSF

Insulin-like growth factor-1 (IGF-1) is involved in regulating the Th-1/Th-2 balance, favoring the development of the Th-2 compartment which enhances fibrosis, one of the main characteristics of Chronic Lung Disease (CLD) in premature newborns. Limited data is available concerning a possible association between early epithelial lining fluid (ELF) concentrations of IGF-1 (total and free forms), IGF-binding protein-3 (IGFBP-3), beta2-microglobulin and subsequent development of CLD in preterm neonates. If neutropenic, preterm neonates are frequently treated with recombinant human granulocyte colony stimulating factor (rhG-CSF). The objective of the study was to correlate ELF concentrations of IGF-1 and beta2 microglobulin during the first week of life both in non-neutropenic and in rhGCSF-treated neutropenic preterm neonates, with subsequent development in CLD. Thirty preterm neonates with Respiratory Distress Syndrome (6 with neutropenia) were studied. Eleven out of 24 non-neutropenic preterm infants (46%) and all of the six neutropenic subjects (100%) developed CLD. With the exception of first day values, there was a clear similarity in the behaviors of assayed molecules between non-neutropenic and neutropenic patients developing CLD. Non-neutropenic patients without CLD showed significantly lower values of free IGF-1 and beta2M both on days 1 and 3. Total IGF-I and cell counts were different only on the 3rd day. Conclusions: 1) the mechanisms leading to CLD might be mediated by high levels of IGF-family molecules soon after birth 2) beta2M could be a marker of increased bronchoalveolar lavage fluid cellularity with potential inflammatory properties 3) G-CSF treatment induces an increased synthesis of IGF-1 molecules by cells recruited in the lung, with possible enhancement of the fibrogenic mechanisms.     

Soluble transferrin receptors and reticulocyte hemoglobin concentration in the assessment of iron deficiency in hemodialysis patients

BACKGROUND: Diagnosing iron deficiency in hemodialysis (HD) patients is crucial for correct anemia management. Hypochromic erythrocytes appear to be the best available marker, but they are often unavailable. Transferrin saturation (TSAT) and ferritin are also indicated as reference markers by guidelines. We evaluated the usefulness of soluble transferrin receptor (s-TfR) and reticulocyte hemoglobin concentration (CHr), which have been recently proposed as more sensitive functional iron deficiency indicators. METHODS: A single-center unselected cohort of 39 chronic HD patients underwent a cross-sectional determination of hemoglobin (Hb), hematocrit (Hct), CHr, transferrin, iron, TSAT, ferritin, folate, vitamin B12 and s-TfR. Twenty-nine patients (74.4%) were treated with subcutaneous erythropoietin (EPO) at a dose of 122 +/- 98 U/kg/week and 24 patients (61.5%) were treated with intravenous (i.v.) iron gluconate, 62.5 mg/week. RESULTS: Hb was 11.1 +/- 1.2 g/dL, Hct 34.4 +/- 3.7%, CHr 32.7 +/- 3.8 pg, transferrin 170 +/- 31 mg/dL, iron 60.2 +/- 25.9 mg/dL, TSAT 30 +/- 18%; ferritin 204 +/- 219 ng/mL, folate 4.2 +/- 1.0 mcg/L, vitamin B12 0.58 +/- 0.15 mcg/L, and s-TfR 1.94 +/- 0.83 mg/L. Both TSAT and s-TfR significantly correlated with CHr, but no relationship could be found between s-TfR and TSAT or between s-TfR and ferritin. Dividing the population into two groups based on iron repletion (ferritin >100 ng/mL and TSAT >20%) we found no differences for CHr levels and significantly lower levels of s-TfR in the replete group (s-TfR 1.71 +/- 0.70 vs. 2.29 +/- 0.90 mg/L; p=0.033). Analysis of 2x2 tables demonstrated that 44% of patients with TSAT >20% had elevated (>1.5 mg/L) s-TfR, indicating a possible functional iron deficiency, but covariance analysis showed that TSAT had a better correlation to CHr. CONCLUSIONS: No clear-cut advantages in the use of CHr content and s-TfR levels as single diagnostic tests could be demonstrated by this cross-sectional study. However, our results suggest that the combined use of TSAT <20% and s-TfR >1.5 mg/L (therefore, including all patients with low TSAT, but also patients with high s-TfR despite normal TSAT) could improve functional iron deficiency detection in dialysis patients suspected of having inflammatory conditions.