Evaluation of operative risk in de novo familial amyloid polyneuropathy retransplantation

Familial amyloid polyneuropathy (FAP) is the most common hereditary amyloidosis, characterized by progressive peripheral sensory and motor neuropathy. The livers of patients with FAP are used in domino liver transplantation in selected cases to increase the number of grafts available. In our department 10 patients underwent liver retransplantation (ReLTx) in the absence of liver dysfunction by de novo FAP after domino liver transplantation. Our aim was to compare the differences in the consumption of blood products and intraoperative hemodynamic support among patients with FAP undergoing liver transplantation (LTx) and patients with de novo FAP undergoing ReLTx in the same time frame. The anesthetic records of all patients who underwent LTx for FAP and ReLTx for de novo FAP were analyzed, from January 2009 to May 2014. Patients were divided into 2 groups: group 1 patients with FAP, and group 2 patients with de novo FAP. Statistical differences in the value of preoperative creatinine were found. Hemoglobin levels, preoperative international normalized ratio (INR), use of blood products, aminergic support, and surgical time showed no statistical difference. Major bleeding rates would be expected in patients undergoing ReLTx. Changes in renal function, chronic immunosuppressive therapy, and age may contribute to the increase in intraoperative complications. We did not find statistically significant differences, leading us to the conclusion that de novo FAP does not seem to be a predictor of perioperative risk.

Nonurgent commercial air travel after nonhemorrhagic cerebrovascular accident

Nonurgent commercial air travel in patients who have experienced a nonhemorrhagic cerebrovascular accident (CVA) may occur, particularly in the elderly traveling population. A recent CVA, particularly occurring during a person's travel, presents a significant challenge to the patient, companions, family, and health care team. Specific medical recommendation, based on accumulated scientific data and interpreted by medical experts, is needed so that travel health care professionals can appropriately guide the patient. Unfortunately, such recommendations are almost entirely lacking despite the relative frequency of CVA and air travel. This article reviews the existing recommendations with conclusions based on both these limited data and rationale conjecture.

Molecular basis of bicarbonate membrane transport in the male reproductive tract

Bicarbonate (HCO₃⁻) membrane transport systems are crucial players in the physiology of several tissues. The molecular basis of HCO₃⁻ membrane transport is of major physiological relevance since this ion is involved in the establishment of intracellular and extracellular ionic composition, osmolariy and pH. The membrane HCO₃⁻ transporters are divided in two main families: solute carrier 4 (SLC4) and solute carrier 26 (SLC26), although HCO₃⁻ concentration can also be regulated by the cystic fibrosis transmembrane regulator (CFTR). In most tissues the SLC4 family represents the majority of HCO₃⁻ transporters members, which can be divided in two subgroups: the Na⁺-dependent and the Na⁺-independent transporters. The SLC26 family consists of ten members that can transport diverse ions besides HCO₃⁻. In the male reproductive tract, HCO₃⁻ transport occurs in several processes in order to assure a correct pursuance of the spermatogenetic event and spermatozoa capacitation, being also necessary for egg fertilization. Indeed, the formation of competent spermatozoa, the maintenance of an adequate ductal luminal milieu and spermatozoa capacitation are highly dependent of ionic balance and pH. Perturbations in these processes result in reduced male reproductive health and consequently male subfertility and/or infertility. Thus, it is imperative to understand HCO₃⁻ transport dynamics in order to identify and counteract possible alterations related with reduced male fertility caused by pathological conditions. Herein, we will review the major families and subfamilies of HCO₃⁻ membrane transport, discussing the molecular basis of HCO₃⁻ transport in the male reproductive tract and its role in male-associated subfertility and/or infertility.

Identification of androgen receptor variants in testis from humans and other vertebrates

The androgen receptor (AR) is a ligand-activated transcription factor member of the nuclear receptor superfamily. The existence of alternatively spliced variants is well recognised for several members of this superfamily, most of them having functional importance. For example, several testicular oestrogen receptor variants have been suggested to play a role in the regulation of spermatogenesis. However, information on AR variants is mostly related to cancer and androgen insensitivity syndrome (AIS) cases. The objective of this study was to investigate the expression of AR variants in the testis from humans and other vertebrates. Four AR variants [ARΔ2(Stop) , ARΔ2(23Stop) , ARΔ3 and ARΔ4(120)] were identified in human testis. ARΔ2(Stop) and ARΔ3, with exon 2 or 3 deleted, respectively, were also expressed in human liver, lung, kidney and heart. In addition, ARΔ2(Stop) was expressed in rat and gilthead seabream testis, while an ARΔ3 was detected in African clawed frog testis. This is the first report revealing the existence of AR variants in the testis of evolutionarily distant vertebrate species and in nonpathological tissues. These data suggest the functional importance of these novel AR forms and demonstrate a complexity in AR signalling that is not exclusive of pathological conditions.

Regucalcin is broadly expressed in male reproductive tissues and is a new androgen-target gene in mammalian testis

Regucalcin (RGN) is a calcium (Ca2+)-binding protein which regulates intracellular Ca2+homeostasis by modulating the activity of enzymes regulating Ca2+concentration and enhancing Ca2+-pumping activity. Several studies have described the pivotal role of proper Ca2+homeostasis regulation to spermatogenesis and male fertility. Recently,RGNwas identified as a sex steroid-regulated gene in prostate and breast; however, a possible role of RGN in spermatogenesis has not been examined. In this study, the expression and localization of RGN in rat and human testis, and other rat reproductive tissues was analyzed. Moreover, we studied whether RGN protein was present in seminiferous tubule fluid (STF). Finally, we examined the effect of 5α-dihydrotestosterone (DHT) on the expression ofRgnmRNA in rat seminiferous tubules (SeT) culturedex vivo. The results presented in this study show that RGN is expressed in Leydig and Sertoli cells, as well as in all types of germ cells of both rat and human testis. RGN is also expressed in rat prostate, epididymis, and seminal vesicles. Moreover, RGN protein is present in rat STF. The results also demonstrate thatRgnexpression is age dependent in rat testis, and is upregulated by the non-aromatizable androgen DHT in rat SeT culturedex vivo. Taken together, these findings indicate thatRgnis a novel androgen-target gene in rat testis and that it may have a role in male reproductive function, particularly in the control of spermatogenesis.