Co‐Expression of Leptin and Oestrogen Receptors in the Preoptic‐Hypothalamic Area

The interaction between the reproductive axis and energy balance suggests that leptin acts as a possible mediator. This hormone acts in the regulation of metabolism, feeding behaviour and reproduction. Animals homozygous for the gene ‘ob’ (ob/ob) are obese and infertile, and these effects are reversed after systemic administration of leptin. Thus, the present study aimed to determine: (i) whether cells that express leptin also express oestrogen receptors of type‐α (ER‐α) or ‐β (ER‐β) in the medial preoptic area (MPOA) and in the arcuate (ARC), dorsomedial (DMH) and ventromedial hypothalamic nucleus and (ii) whether there is change in the gene and protein expression of leptin in these brain areas in ovariectomised (OVX) animals when oestrogen‐primed. Wistar female rats with normal oestrous cycles or ovariectomised oestrogen‐primed or vehicle (oil)‐primed were utilised. To determine whether there was a co‐expression, immunofluorescence was utilised for double staining. Confocal microscopy was used to confirm the co‐expression. The technique of real‐time polymerase chain reaction and western blotting were employed to analyse gene and protein expression, respectively. The results obtained showed co‐expression of leptin and ER‐α in the MPOA and in the DMH, as well as leptin and ER‐β in the MPOA, DMH and ARC. However, we did not detect leptin in the MPOA, ARC and DMH using western blotting and there was no statistical difference in leptin gene expression in the MPOA, DMH, ARC, pituitary or adipose tissue between OVX rats treated with oestrogen or vehicle. In conclusion, the results obtained in the present study confirm that the brain is also a source of leptin and reveal co‐expression of oestrogen receptors and leptin in the same cells from areas related to reproductive function and feeding behaviour. Although these data corroborate the previous evidence obtained concerning the interaction between the action of brain leptin and reproductive function, the physiological relevance of this interaction remains uncertain and additional studies are necessary to elucidate the exact role of central leptin.     

Ulnar Neuropathy At Elbow (UNE): Clinical And Electrophysiological Study Of 279 Cases

It is well known that in a small proportion of patients with peripheral neuropathy a cause is not found; on the other hand, it is also possible that extensive investigations reveal more than one possible cause of peripheral neuropathy, especially in older patients, raising a different kind of diagnostic problem. The aim of this study was to investigate the occurrence of “multifactorial neuropathy” in a population of patients with peripheral neuropathy, and the modalities of interaction when various causes are implicated in determining the features of neuropathy. In a series of 62 consecutive patients with peripheral neuropathy who underwent an extensive diagnostic work-up, more than one possible cause for a single patient was found in 24 patients (38.7%), and at least 3 causes in 9 patients (14.5%). Common causes of neuropathy, such as diabetes, alcohol, drugs, Charcot-Marie-Tooth disease, and cryoglobulinemia were more often implicated in multifactorial neuropathy. In 8 additional patients, neuropathic motor and sensory impairment was complicated by coexistent diseases (Parkinson's disease, osteoarthrosis, lumbal stenosis). Patients with multifactorial neuropathy were older than patients with neuropathy due to a single cause (mean age: 66.8 ± 9.6 vs. 62.2 ± 11.9), and had a significantly greater disability on Rankin scale (28/32 with Rankin grade 2 or more, vs. 15/30; p = 0.002). Possible mechanisms of interaction between two or more causes of neuropathy are the following: a primary neuropathic condition is worsened or revealed by an additional superimposed cause; two coexisting causes concur to determine the features of neuropathy, for instance influencing respectively motor and sensory symptoms; a unique cause produces neuropathic damage through different mechanisms (this is typically the case of malignancies, and in particular lymphoma); the significance of some potential factors of neuropathic damage, such as monoclonal gammopathy, may be difficult to be ascertained, thus their role as a cause of neuropathy remains elusive. In addition, the disability due to neuropathy may be complicated by other concurrent neurologic or non-neurologic conditions causing additional motor or sensory impairment. Thus it is also advisable to have a complete screening in patients with an obvious cause of peripheral neuropathy, as it could be made worse by another coexistent cause, and in older patients this evenience is not uncommon. This is especially important when a treatable additional cause is revealed.     

Modulation of gap junction mediated intercellular communication in TM3 Leydig cells

Long-term modulation of intercellular communication via gap junctions was investigated in TM3 Leydig cells, under low and high confluence states, and upon treatment of the cells for different times with activators of protein kinase A (PKA) and protein kinase C (PKC). Cells in low confluence were readily coupled, as determined by transfer of the dye Lucifer Yellow; on reaching confluence, the cells uncoupled. Western blots and RT-PCR revealed that connexin 43 (Cx43) was abundantly expressed in TM3 Leydig cells and its expression was decreased after the cells achieved confluence. Stimulation of PKA or PKC induced a decrease in cell-cell communication. Staurosporin, an inhibitor of protein kinases, increased coupling and was able to prevent and reverse the uncoupling actions of dibutyryl cAMP and 12-O-tetradecanoyl-phorbol-13-acetate (TPA). Under modulation by confluence, Cx43 was localized to the appositional membranes when cells were coupled and was mainly in the cytoplasm when they were uncoupled. In addition, cAMP and TPA reduced the surface membrane labeling for Cx43, whereas staurosporin increased it. These data show a strong correlation between functional coupling and the membrane distribution of Cx43, implying that this connexin has an important role in intercellular communication between TM3 cells. Furthermore, increased testosterone secretion in response to luteinizing hormone was accompanied by a decrease in intercellular communication, suggesting that gap junction mediated coupling may be a modulator of hormone secretion in TM3 cells.     

Exposure of nursing personnel to electromagnetic fields in neonatal intensive care

Electromagnetic fields (EMF) are recognised as a source of environmental pollution for workers and people resident in exposed areas. The level of exposure to EMFs of the nurses working in the Siena Neonatal Intensive Care Unit, during two workdays was recorded and peak levels > 10 mG (1 microT) were registered well above an almost permanence exposure at > 2 mg G. The application of existing standard, cautionary criteria and rules would suggest protective or restrictive measures against EMF exposure for these workers.     

Effects of acute stress on the day of proestrus on sexual behavior and ovulation in female rats: participation of the angiotensinergic system

Physical or emotional stress can affect the female reproductive physiology and angiotensin II (Ang II) is a hormone that participates in the stress response and also in the control of reproductive hormones. The present study aimed at evaluating the effects of acute stress in the morning and afternoon of proestrus on sexual behavior and ovulation and the participation of Ang II in the stress-induced effects. Female rats with regular estrous cycles were used. Several different stress protocols were tested in the morning and in the afternoon of proestrus: restraint stress 10 min; restraint stress 1 h and ether stress, respectively. The participation of Ang II was evaluated by injecting Ang II receptor antagonists (losartan and PD123319) 15 min before stress. The lordosis quotient was recorded and the number of oocytes was counted. Plasma levels of luteinizing hormone, progesterone, prolactin and corticosterone were measured. All types of stress in the morning of proestrus induced a reduction in the number of oocytes. Restraint stress (1 h) in the afternoon of proestrus induced a significant reduction in the lordosis quotient. Peripheral and central losartan, but not PD123319, injections partly reverted the effects of stress on ovulation in the morning of proestrus. Acute stress in the morning of proestrus also reduced luteinizing hormone, progesterone and prolactin surges later on the same day. In conclusion, acute stress on the day of proestrus can affect female reproductive physiology. Moreover, the angiotensinergic system, through AT(1) receptors, participates in the effects of acute stress in the morning of proestrus.     

Contrast‐enhanced sonography in the diagnosis of hepatic hemangiomas: Atypical appearance due to the washout of microbubbles

Contrast‐enhanced sonography (CEUS) examination permits identification of hemangioma of the liver in most cases. This method is particularly useful when the ultrasound pattern is atypical on standard grayscale examination. CEUS appearances suggestive of hemangioma are peripheral globular enhancement, progression of enhancement toward the center of the nodule, and persistence of enhancement in the late phase. We present seven cases of hemangioma, which were atypical on CEUS examination due to washout during the portal and late phases, resulting in a hypoenhanced appearance compared with the adjacent liver parenchyma. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound 41 :361–365, 2013