The 18S rRNA Methyltransferase DIMT-1 Regulates Lifespan in the Germline Later in Life.

Ribosome heterogeneity has emerged as an important regulatory control feature for determining which proteins are synthesized, however, the influence of age on ribosome heterogeneity is not fully understood. Whether mRNA transcripts are selectively translated in young versus old cells and whether dysregulation of this process drives organismal aging is unknown. Here we examined the role of ribosomal RNA (rRNA) methylation in maintaining appropriate translation as organisms age.

Surgical Reconstruction of Stage 3 and 4 Pressure Injuries: A Literature Review and Proposed Algorithm from an Interprofessional Working Group.

Objective: Stage 3 and 4 pressure injuries (PIs) present an enormous societal burden with no clearly defined interventions for surgical reconstruction. The authors sought to assess, via literature review and a reflection/evaluation of their own clinical practice experience (where applicable), the current limitations to the surgical intervention of stage 3 or 4 PIs and propose an algorithm for surgical reconstruction.

Methods: An interprofessional working group convened to review and assess the scientific literature and propose an algorithm for clinical practice.

Analysis of births, abortions and maternal mortality in adolescents in Ecuador from 2013 to 2016.

Introduction: Adolescent pregnancy is associated to school desertion, violence, termination of pregnancy under suboptimal conditions, obstetric complications and other consequences that can put the woman's quality of life at risk and of those that surround her. The purpose of this study is to describe the situation and tendencies of adolescent pregnancies, abortions and maternal deaths between 2013 and 2016 in Ecuador.

Methods: This cross-sectional study uses secondary data from national Ecuadorian vital statistics reports of adolescents between 10 and 19 years old.

Efficient Enzyme-Free Biomimetic Sensors for Natural Phenol Detection.

The development of sensors and biosensors based on copper enzymes and/or copper oxides for phenol sensing is disclosed in this work. The electrochemical properties were studied by cyclic and differential pulse voltammetry using standard solutions of potassium ferrocyanide, phosphate/acetate buffers and representative natural phenols in a wide pH range (3.0 to 9.

Inside look at laparoscopic colectomy.

Laparoscopic colectomy has developed into a viable alternative to colon surgery. This paper presents an overview of the development and current status of laparoscopic surgery of the colon with a brief review of the evidence of efficacy of laparoscopic surgery in cancer management. The experience with laparoscopic surgery of the colon at a tertiary hospital in Puerto Rico is discussed with review of 142 consecutive cases treated for diverticulosis, cancer or polyps performed from 2005-2010.

Current and future application of genetic toxicity assays: the role and value of in vitro mammalian assays.

With the advent of new technologies (e.g., genomics, automated analyses, and in vivo monitoring), new regulations (e.

Comparison between open and laparoscopic appendectomy in non-complicated appendicitis.

Background/objective: An extensive web search failed to provide studies from Puerto Rico regarding whether open (OA) or laparoscopic appendectomy (LA) should be performed for non-complicated appendicitis. Our goal is to compare these techniques in terms of time at operating room (OR), length of surgery, hospital stay, pain medication requirements, in-hospital complications and readmissions.

Methods: 126 patients (64 OA; 62 LA) with non-complicated appendicitis were studied retrospectively.

Experience with hand assisted laparoscopic surgery of the colon.

Background: Hand assisted laparoscopic colectomy (HALS) has been shown to have the advantages of laparoscopic colectomy in terms of pain, recovery and length of hospital stay. Studies have shown similar outcomes in laparoscopic colectomy as in open surgery. There is a learning curve to HALS, the operative time is longer, and it is more difficult than open surgery and requires specialized equipment.

N,N-dimethyl-thioamphetamine and methyl-thioamphetamine, two non-neurotoxic substrates of 5-HT transporters, have scant in vitro efficacy for the induction of transporter-mediated 5-HT release and currents.

We studied two non-neurotoxic amphetamine derivatives (methyl-thioamphetamine, MTA and N,N-dimethylMTA, DMMTA) interacting with serotonin (5-HT) transporters (SERTs) with affinities comparable to that of p-Cl-amphetamine (pCA). The rank order for their maximal effects in inducing both [(3)H]5-HT release from rat brain synaptosomes or hSERT-expressing HEK-293 cells, and currents in hSERT-expressing oocytes, was pCA >> MTA > or = DMMTA. A correlation between drug-induced release and currents is also strengthened by the similar bell shape of the dose-response curves.

Acute morphine administration increases extracellular DA levels in the rat lateral septum by decreasing the GABAergic inhibitory tone in the ventral tegmental area.

We studied the effect of an acute systemic administration of morphine and of a local intra-ventral tegmental area (VTA) infusion of the same drug on extracellular levels of dopamine (DA) in the lateral septum (LS) by in vivo microdialysis in anesthetized rats. The extracellular levels of 5-hydroxytryptamine (5-HT) were also measured in all dialysate samples. The acute systemic administration of morphine dose-dependently increased extracellular levels of DA but not of 5-HT in the LS, in the absence or presence of fluoxetine.

Effects of intermittent exposure to aflatoxin B1 on DNA and RNA adduct formation in rat liver: dose-response and temporal patterns.

We studied the effects of intermittent exposure to aflatoxin B1 (AFB1) on hepatic DNA and RNA adduct formation. Fisher-344 male rats were fed 0.01, 0.

Immunotoxicity of aflatoxin B1 in rats: effects on lymphocytes and the inflammatory response in a chronic intermittent dosing study.

We investigated the effects of aflatoxin B1 (AFB1) on isolated splenic lymphocytes and the histo-morphologic changes in the spleens and liver of Fisher-344 male rats. Weaned animals were fed chow diets that contained 0, 0.01, 0.

Unscheduled DNA synthesis assay in mammalian spermatogenic cells: an update.

The unscheduled DNA synthesis (UDS) assay measures DNA repair in response to DNA damage. To date, 59 chemicals plus UV and X rays have been tested for UDS in spermatogenic cells of humans, rabbits, rats, and mice. In vivo, in vitro, and combined in vivo/in vitro procedures have been used.

Effects of intermittent exposures of aflatoxin B(1) on hepatic and testicular glutathione S-transferase in rats.

Glutathione S-transferase (GST) plays a major role in the detoxification of the potent hepatocarcinogen aflatoxin B(1) (AFB(1)). This study evaluated the effects of intermittent exposures to AFB(1) on hepatic and testicular GST in rats. Male Fischer 344 rats were fed diets containing AFB(1) (0, 0.

Differential sensitivities of spermatogonial and postspermatogonial cell stages of the mouse to induction of unscheduled DNA synthesis by ethyl- and methyl-nitrosourea.

An autoradiographic procedure was used to measure unscheduled DNA synthesis (UDS, DNA repair synthesis) in spermatogonial and postspermatogonial cell stages of mice after treatment with two doses of N-ethyl-N-nitrosourea (ENU) and N-methyl-N-nitrosourea (MNU). Significant levels of UDS were measured in type A spermatogonia, meiotic spermatocytes, round spermatids, and early elongating spermatids but not in mature spermatids. The extent of UDS varied according to the germ cell stage and the dose.

Temporal patterns of DNA adduct formation and glutathione S-transferase activity in the testes of rats fed aflatoxin B1: a comparison with patterns in the liver.

Fisher-344 male rats were fed 1.6 ppm of aflatoxin B1 (AFB1) continuously and intermittently for several weeks. At various time periods, DNA was isolated from the testes and livers and analyzed for AFB1-DNA adducts.

A procedure to study unscheduled DNA synthesis in rat spermatogenic cells in vivo: strain differences between Fisher-344 and Sprague-Dawley rats.

A liquid scintillation counting (LSC) procedure was used to study unscheduled DNA synthesis (UDS) in pachytene spermatocytes and spermatids from Fisher-344 (F344) and Sprague-Dawley (SPD) rats treated with methyl methanesulfonate (MMS). MMS induced a large, dose-dependent, UDS response in pachytene spermatocytes from both rat strains. On average, F344 pachytene spermatocytes showed a larger UDS response than those of SPD rats.

Cryosurgery on the Treatment of Hepatic Tumors.

BACKGROUND: Primary and metastatic tumors in the liver are difficult to treat. When surgical resection is not feasible, cryotherapy is one of the several alternative approaches. METHODS: The data on outcomes from hepatic resections are reviewed, and the rationale and techniques of performing cryosurgery for unresectable hepatic cancers are described.

Formation of etheno and oxoethyl adducts in liver DNA from rats exposed subchronically to urethane in drinking water and ethanol.

Exposure of Fisher-344 male rats to 10 000 ppm of urethane in drinking water for up to 90 days or in 5% ethanol for up to 14 days caused the formation of 7-[2'-oxoethyl]guanine (OEG) and 1,N(6)-ethenoadenine (epsilon A) in liver DNA. Mild-acid DNA hydrolysates were analyzed by high-performance liquid chromatography with photodiode array detection and fluorometry. The identification of OEG and epsilon A was confirmed by coelution with the authentic standards.

Unusual cases of hyperparathyroidism.

The history, physical and radiologic findings, treatment and pathology in five unusual cases of hyperparathyroidism is presented. The hyperparathyroidism was caused by a large (113 grams) mediastinal adenoma in the first patient, who is alive 25 years after surgery. A parathyroid carcinoma with compression of the esophagus was documented in the second patient.

Induction of DNA damage by urethane in mouse testes: DNA binding and unscheduled DNA synthesis.

The extent and persistence of DNA damage and repair were investigated in mouse spermatogenic cells exposed in vivo to urethane (ethyl carbamate, EC). Adult male mice exposed to [3H]EC at 10-1,000 mg/kg were sacrificed 12 hr later. EC/metabolite binding to liver and testicular DNA and to sperm heads from the vasa deferentia was measured.

Mutagenicity, metabolism, and DNA interactions of urethane.

Urethane, a known animal carcinogen, has been the subject of intensive research efforts spanning 40 years. Recent concerns have focused on the presence of urethane in a variety of fermented foods and alcoholic beverages, although no epidemiological studies or human case reports have been published. Much information is available about the mutagenesis, metabolism, and DNA interactions of urethane in experimental systems.