Ibero⁻American Consensus on Low- and No-Calorie Sweeteners: Safety, Nutritional Aspects and Benefits in Food and Beverages

International scientific experts in food, nutrition, dietetics, endocrinology, physical activity, paediatrics, nursing, toxicology and public health met in Lisbon on 2⁻4 July 2017 to develop a Consensus on the use of low- and no-calorie sweeteners (LNCS) as substitutes for sugars and other caloric sweeteners. LNCS are food additives that are broadly used as sugar substitutes to sweeten foods and beverages with the addition of fewer or no calories. They are also used in medicines, health-care products, such as toothpaste, and food supplements. The goal of this Consensus was to provide a useful, evidence-based, point of reference to assist in efforts to reduce free sugars consumption in line with current international public health recommendations. Participating experts in the Lisbon Consensus analysed and evaluated the evidence in relation to the role of LNCS in food safety, their regulation and the nutritional and dietary aspects of their use in foods and beverages. The conclusions of this Consensus were: (1) LNCS are some of the most extensively evaluated dietary constituents, and their safety has been reviewed and confirmed by regulatory bodies globally including the World Health Organisation, the US Food and Drug Administration and the European Food Safety Authority; (2) Consumer education, which is based on the most robust scientific evidence and regulatory processes, on the use of products containing LNCS should be strengthened in a comprehensive and objective way; (3) The use of LNCS in weight reduction programmes that involve replacing caloric sweeteners with LNCS in the context of structured diet plans may favour sustainable weight reduction. Furthermore, their use in diabetes management programmes may contribute to a better glycaemic control in patients, albeit with modest results. LNCS also provide dental health benefits when used in place of free sugars; (4) It is proposed that foods and beverages with LNCS could be included in dietary guidelines as alternative options to products sweetened with free sugars; (5) Continued education of health professionals is required, since they are a key source of information on issues related to food and health for both the general population and patients. With this in mind, the publication of position statements and consensus documents in the academic literature are extremely desirable.

Mucinous adenocarcinoma associated with fistula in ano: report of a case

We present a case of the rare occurrence of a mucus-secreting adenocarcinoma originating in an anal gland. A 37-year-old diabetic man had an anal fistulotomy 16 years before. He had four ischiorectal abscesses in a 6-month period. A seton was inserted in a complex fistula tract in the left anterior lateral aspect. Due to delayed healing, a new surgical exploration was carried out; pathological analysis of the curetted mucinous tissue revealed a mucoid adenocarcinoma. Surgical resection is the first choice of curative treatment, and additional treatments include chemotherapy, radiotherapy and brachytherapy.

Human immunodeficiency virus type 1 pharmacogenomics in clinical practice: relevance of HIV-1 drug resistance testing (Part 1)

Throughout most of the past century, physicians could offer patients no treatments for infections caused by viruses. The experience with treatment of infection by human immunodeficiency virus (HIV) has changed the way healthcare workers deal with viral infections and has triggered a growing rate of discovery and use of antiviral agents, the first fruits of the expanding genomics revolution. HIV treatment also provides an informative paradigm for pharmacogenomics because control of infection and its consequences is limited by the development of viral drug resistance and by host factors. This report summarizes studies published to date on the significance of testing of HIV-1 resistance to antiretroviral drugs. The only Food and Drug Administration-approved kit for HIV drug resistance testing by genotypic sequencing is commercially available through Visible Genetics, Inc. Genotyping sequencing alone is most likely an adequate test to assist in the therapeutic decision-making process for previous regimen failure, for treatment-naïve patients in areas of high prevalence of transmitted resistant virus, and for pregnant women. However, in exceptional cases of highly complex mutation patterns and extensive cross-resistance, it may be useful to obtain a phenotype test, because that result may more easily identify drugs to which virus is least resistant. There are no published clinical trials results on the usefulness of the so-called virtual phenotype over genotypic sequencing alone. Not only has the paradigm of viral pharmacogenomics in the form of HIV genotypic sequencing been useful in treating other viral diseases, but it is also important to the real-life implementation of the growing discipline ofgenomics or molecular medicine. The application of this paradigm to the thousands of potential therapeutic targets that have become available through the various human genome projects will certainly gradually change the landscape of diagnosis and management of many diseases, including cancer.

Human Immunodeficiency Virus Type 1 Pharmacogenomics in Clinical Practice: Relevance of HIV-1 Drug Resistance Testing (Part 2)

Throughout most of the past century, physicians could offer patients no treatments for infections caused by viruses. The experience with treatment of infection by human immunodeficiency virus (HIV) has changed the way healthcare workers deal with viral infections and has triggered a growing rate of discovery and use of antiviral agents, the first fruits of the expanding genomics revolution. HIV treatment also provides an informative paradigm for pharmacogenomics because control of infection and its consequences is limited by the development of viral drug resistance and by host factors. This report summarizes studies published to date on the significance of testing of HIV-1 resistance to antiretroviral drugs. The only Food and Drug Administration-approved kit is commercially available through Visible Genetics, Inc., for HIV drug resistance testing by genotypic sequencing. Genotyping sequencing alone is most likely an adequate test to assist in the therapeutic decision-making process in cases of previous regimen failure, treatment-naïve patients in areas of high prevalence of transmitted resistant virus, and pregnant women. However, in exceptional cases of highly complex mutation patterns and extensive cross-resistance, it may be useful to obtain a phenotype test, because that result may more easily identify drugs to which the virus is least resistant. There are no published clinical trial results on the usefulness of the so-called virtual phenotype over genotypic sequencing alone. The paradigm of viral pharmacogenomics in the form of HIV genotypic sequencing has been not only useful to the treatment of other viral diseases but also important to the real-life implementation of the growing discipline of genomics or molecular medicine. The application of this paradigm to the thousands of potential therapeutic targets that have become available through the various human genome projects will certainly gradually change the landscape of diagnosis and management of many diseases, including cancer.

Effects of low-level lead exposure on hypothalamic hormones and serum progesterone levels in pregnant guinea pigs

Pregnant guinea pigs were given a daily oral dose of 0, 5.5, or 11 mg lead (as lead acetate) per kg body weight during days 22-52 or 22-62 of gestation. Maternal serum progesterone levels were measured at the end of treatment, as well as hypothalamic levels of gonadotropin-releasing hormone (GnRH) and somatostatin (SRIF) in both the mothers and fetuses. Lead-treated dams had lower serum concentrations of progesterone at the end of treatment than did vehicle-treated animals. This effect was statistically significant for the higher Pb dose only. Hypothalamic levels of GnRH and SRIF were reduced in a dose-dependent manner by lead treatment in both dams and fetuses. The reduction of SRIF levels in 52-day-old fetuses was particularly severe (92%) in the 11 mg group. However, neither litter size nor body and organ weights, including placental weight, of the dams and fetuses was significantly affected. The relevance of these hormonal decreases is unknown, but could include decreased reproductive capacity in both the dams and fetuses that does not become apparent until later in the life-cycle.

Reduction of glutamine synthetase activity in astroglia exposed in culture to low levels of inorganic lead

Astroglia serve as a site of lead (Pb) deposition in Pb-exposed animals. Thus, the potential exists for astroglial function to be impaired by elevated intracellular Pb levels. We previously showed that the specific activity of glutamine synthetase (GS), an astroglial enzyme with a key role in glutamate and ammonia metabolism in the brain, is reduced in fetal guinea pigs exposed to low levels of lead. This observation indicates either a direct effect of Pb on astroglia or an indirect systemic effect. The purpose of the present study was to test the hypothesis that Pb directly reduces GS activity in astroglia. Cultured rat astroglia were fed three times per week with medium containing 0, 0.25, 0.5, or 1 microM Pb acetate for 7, 14, or 21 days. Trypan blue dye exclusion, cell number, and GS activity were measured. Lead treatment reduced the ability of cells to exclude trypan blue in a dose- and time-dependent manner, with the greatest reduction (28%) on day 21 in the group treated with 1 microM Pb. Cell numbers were reduced a maximum of 15% on day 15, but were unaffected on days 7 and 21. The effects of Pb exposure on GS activity were much more pronounced. For example, cultures exposed to 0.25 of 1 microM Pb for 7 days showed, respectively, 17 and 52% reduction in activity from the control value. Slightly greater reductions were measured on days 14 and 21. The much greater sensitivity in vitro of GS activity than dye exclusion or cell numbers to low level lead supports a specific enzymatic inhibition. In order to test the possibility that Pb might directly inhibit GS activity Pb-treated cells, we also measured the effect of Pb on GS activity in cytosolic extracts of the cells. Pb inhibited GS activity in a dose-dependent manner ranging from 27% inhibition at 0.1 nM to 67% at 0.1 microM and 100% at 10 microM Pb. These results indicate that astroglial function is vulnerable to Pb exposure, even at low lead levels.

Low level lead neurotoxicity in a pregnant guinea pigs model: neuroglial enzyme activities and brain trace metal concentrations

Specific activities of the astroglial marker glutamine synthetase (GS), and the oligodendroglial marker glycerol-3-phosphate dehydrogenase (GPDH) were measured in the spinal cord of fetal guinea pigs and their dams following chronic exposure to low levels of lead (Pb) during gestation. In addition, the effects of Pb on intracellular trace metals (Cu, Fe, Zn) were measured in the blood, cerebellum and forebrain. Aminolevulinic acid dehydratase (ALAD) and zinc protoporphyrin IX (ZPP) were measured in order to monitor established parameters of Pb-exposure. Pregnant guinea pigs were orally administered 0, 5.5 or 11 mg Pb/kg body weight for 30 or 40 days commencing on day 22 of gestation. Blood Pb levels produced in dams and fetuses were at or near the currently identified "no effect" levels for children (10-30 micrograms/dl). These Pb blood levels produced a significant (P less than 0.05) dose-dependent decrease in GS and GPDH activity in the dams and fetuses. Fe and Zn concentrations in blood, cerebellum and forebrain of both dams and fetuses were significantly (P less than 0.05) decreased in a dose-dependent manner. However, Cu concentrations in the blood, cerebellum and forebrain were decreased in the dams but increased in the fetuses in a dose-dependent fashion. The alteration of trace metal concentrations is a proposed mechanism of Pb neurotoxicity. Blood ALAD activity was significantly (P less than 0.05) decreased and ZPP levels were significantly (P less than 0.05) increased, as expected in Pb-exposed animals. This study presents the first biochemical evidence for the alteration of neuroglial function at low levels of Pb exposure and focuses attention on the fetus as an important Pb target.