Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre-including this research content-immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active.

Background We conducted an observational study of 15 patients from a Southeastern area of Mexico with symptoms compatible with SARS-Cov-2, which were treated with the antiviral amantadine. Methodology In this study, data were collected from 15 individuals with clinical symptoms of COVID-19 infection, which were treated on an ambulatory basis with 100 mg of amantadine for a period of 14 days. Results This drug demonstrated its effectiveness, as patients recovered successfully with this treatment without the necessity of attending a hospital to use mechanical ventilation. All patients developed IgG antibodies to SARS-Cov-2. Conclusion Amantadine can be used as a viable and cost-effective alternative for treating people with severe acute respiratory syndrome (SARS-Cov-2) on an ambulatory basis, while the vaccine is not available.

Evidence indicates that prolactin plays a crucial role in the normal function and development of the prostate, but abnormal high levels of the hormone are associated with hyperplasia and cancer of the gland. Aims: The present study was designed to describe the progressive specific histological abnormalities in the prostate of rats with chronic hyperprolactinemia. Material and Methods: Prolactin was administered during 4; 12 or 24 weeks, and the resulting prostatic alterations were compared with control rats, and also with those treated with testosterone, or the combination of prolactin + testosterone. Results: Rats treated with prolactin, testosterone or prolactin + testosterone expressed precancerous histological abnormalities in the dorsolateral and ventral portions of the prostate as early as in 4 weeks of treatment, but in all cases the malignancy increased after 12 or 24 weeks of treatment. Conclusion: Our study confirms that chronic hyperprolactinemia is a cause of prostate precancerous pathologies.

No abstract

BackgroundThe effect of orgasm on the development and shaping of partner preferences may involve a catalysis of the neurochemical mechanisms of bonding. Therefore, understanding such process is relevant for neuroscience and psychology.MethodsA systematic review was carried out using the terms Orgasm, Sexual Reward, Partner Preference, Pair Bonding, Brain, Learning, Sex, Copulation.ResultsIn humans, concentrations of arousing neurotransmitters and potential bonding neurotransmitters increase during orgasm in the cerebrospinal fluid and the bloodstream. Similarly, studies in animals indicate that those neurotransmitters (noradrenaline, oxytocin, prolactin) and others (e.g. dopamine, opioids, serotonin) modulate the appetitive and consummatory phases of sexual behavior and reward. This suggests a link between the experience of orgasm/sexual reward and the neurochemical mechanisms of pair bonding. Orgasm/reward functions as an unconditioned stimulus (UCS). Some areas in the nervous system function as UCS-detection centers, which become activated during orgasm. Partner-related cues function as conditioned stimuli (CS) and are processed in CS-detector centers.ConclusionsThroughout the article, we discuss how UCS- and CS-detection centers must interact to facilitate memory consolidation and produce recognition and motivation during future social encounters.

No abstract

The prostate is an exocrine reproductive gland that participates in ejaculation and it is prone to diseases, including cancer. Aim: In the present study, we assessed the long­term effects of copulation on the development of precancerous lesions in rats, and compared them with testosterone­induced prostatic lesions. Materials and Methods: One group of Wistar males was given 10 copulatory sessions to one ejaculation with ovariectomized, hormone­primed females. Sessions occurred twice per week for a total of ten trials. A second group was exposed to females during the same trials, but physical contact was prevented. In addition, each group received a subcutaneous implant in the back either filled with testosterone propionate (T, 100 mg/kg) or empty. This resulted in four subgroups: 1) Control + No sex, 2) Control + Sex, 3) T + No sex and 4) T + Sex. Two days after the 10th trial all the males were sacrificed for prostate histo logy (H&E) and hormone analysis (testosterone and prolactin). Results: Males from the group Control + No sex expressed normal histo logy. However, those in the groups Control + Sex and T + No sex expressed metaplasia and dysplasia in both the dorsolateral and ventral portions of the prostate, respectively. Interestingly, males from the group T + Sex expressed dysplasia in the dorsolateral prostate only, but not in the ventral prostate. Conclusions: These results indicate that constant copulation may facilitate the development of prostatic lesions in males with normal levels of testosterone. However, copulation induces less lesions in the ventral prostate of males treated with testosterone.

Among the different species of mammals, the expression of maternal behavior varies considerably, although the end points of nurturance and protection are the same. Females may display passive or active responses of acceptance, recognition, rejection/fear, or motivation to care for the offspring. Each type of response may indicate different levels of neural activation. Different natural stimuli can trigger the expression of maternal and paternal behavior in both pregnant or virgin females and males, such as hormone priming during pregnancy, vagino-cervical stimulation during parturition, mating, exposure to pups, previous experience, or environmental enrichment. Herein, we discuss how the olfactory pathways and the interconnections of the medial preoptic area (mPOA) with structures such as nucleus accumbens, ventral tegmental area, amygdala, and bed nucleus of stria terminalis mediate maternal behavior. We also discuss how the triggering stimuli activate oxytocin, vasopressin, dopamine, galanin, and opioids in neurocircuitries that mediate acceptance, recognition, maternal motivation, and rejection/fear.