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Neurobiological studies of the model species, Aplysia californica (Mollusca, Gastropoda, Euopisthobranchia), have helped advance our knowledge of the neural bases of different forms of learning, including sensitization, a non-associative increase in withdrawal behaviors in response to mild innocuous stimuli. However, our understanding of the natural context for this learning has lagged behind the mechanistic studies. Previous studies, which exclusively used artificial stimuli, such as electric shock, to produce sensitization, left open the question of which stimuli might cause sensitization in nature. Our laboratory first addressed this question by testing for short and long-term sensitization after predatory attack by a natural predator, the spiny lobster. In the present study, we tested for sensitization after attack by a very different predator, the predacious sea-slug, Navanax inermis (Mollusca, Gastropoda, Euopisthobranchia). Unlike the biting and prodding action of lobster attack, Navanax uses a rapid strike that sucks and squeezes its prey in an attempt to swallow it whole. We found that Navanax attack to the head of Aplysia caused strong immediate sensitization of head withdrawal, and weaker, delayed, sensitization of tail-mantle withdrawal. By contrast, attack to the tail of Aplysia resulted in no sensitization of either reflex. We also developed an artificial attack stimulus that allowed us to mimick a more consistently strong attack. This artificial attack produced stronger but qualitatively similar sensitization: Strong immediate sensitization of head withdrawal and weaker sensitization of tail-mantle withdrawal after head attack, immediate sensitization in tail-mantle withdrawal, but no sensitization of head withdrawal after tail attack. We conclude that Navanax attack causes robust site-specific sensitization (enhanced sensitization near the site of attack), and weaker general sensitization (sensitization of responses to stimuli distal to the attack site). We also tested for long-term sensitization (lasting longer than 24 h) after temporally-spaced delivery of four natural Navanax attacks to the head of subject Aplysia. Surprisingly, these head attacks, any one of which strongly sensitizes head withdrawal in the short term, failed to sensitize head-withdrawal in the long term. Paradoxically, these repeated head attacks produced long-term sensitization in tail-mantle withdrawal. These experiments and observations confirm that Navanax attack causes short, and long-term sensitization of withdrawal reflexes of Aplysia. They add site-specific sensitization as well as paradoxical long-term sensitization of tail-mantle withdrawal to a short list of naturally induced learning phenotypes in this model species. Together with previous observations of sensitization after lobster attack, these data strongly support the premise that sensitization in Aplysia is an adaptive response to sub-lethal predator attack., (Copyright © 2021 Elsevier Inc. All rights reserved.)

A new indole alkaloid strychnosinol (1) and a new phenolic-glycoside (2) were isolated from the bark and leaves of Strychnos fendleri Sprague & Sandwith, together with six known compounds reported for the first time in this species. The structures of these compounds were determined on the basis of spectroscopic data; mainly those obtained by using (1)H and (13)C NMR (1D and 2D) and mass spectrometry. Strychnosinol (1) and the phenolic glycoside (2) together with compounds 3-8 were evaluated for cytotoxicity against a panel of five tumour cell lines; IC50 values between 0.090 and 0.227 μM for the human tumour cell lines were observed for compound 2.

A series of caracasine acid (1) derivatives were synthesized and evaluated for their in vitro cytotoxicity on human cancer-derived cell lines MCF-7 and PC-3, as well as for other activities such as antibacterial, antileishmanial and antitrypanosomal activity. Compound 1 was more effective than any of its derivatives against tested human cancer cell lines. PC-3 cells were more sensitive than MCF-7 to all compounds, particularly the methyl ester (2), the amide (9) and the epoxide (10). The evaluation of antiparasitic activity revealed that ester derivatives (2-8) and the amide derivative (9) were the most effective antileishmanial and antitrypanosomal compounds, even though their effect on Trypanosoma cruzi was modest. Finally, compound 1 and the derivatives evidenced a broad spectrum of antibacterial activity, as assayed against Gram-positive and Gram-negative bacteria., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The essential oil from leaves of Croton gossypiifolius Vahl. (Euphorbiaceae) was obtained by hydrodistillation, and analyzed by GC/FID and GC/MS. The constituents were identified by their mass spectra and Kovats' indices. Fifty-one compounds accounting for 92% of the oil were detected, and 47 of them were identified. The oil was dominated by oxygenated sesquiterpenes with the major presence of alpha-cedrene oxide (18.6%), spathulenol (16.3%), valencene (5.8%), geranyl-pentanoate (5.3%), alpha-cadinol (4.0%), germacrene D (3.5%) and longifolene (3.3%).

Croton malambo (K.) bark aqueous extract, popularly known in Venezuela as "palomatias" or "torco" was tested for acute toxicity and for its anti-inflammatory and antinociceptive effects using tail flick and writhing syndrome tests models, respectively. Croton malambo aqueous extract (6.15 mg/kg i.p.) administered intraperitoneally had a significant antinociceptive and anti-inflammatory effects compared to acetylsalicylic acid (200mg/kg p.o.) and sodium diclofenac (5.64 mg/kg p.o.). Studies to determine correlation between chemical composition and pharmacological activity are underway.

Although polio is often considered a disease of the past, new symptoms are appearing in patients infected with the polio virus many years ago. Many patients who contracted a paralytic form of poliomyelitis 3, 4, or even 7 decades ago are now relieving their childhood symptoms in what is known as postpolio syndrome.

Worker notification involves informing current and past employees of their risk of disease. It also involves suggesting ways to reduce their risks. The asbestos screening and education programs designed for the building and construction trades unions were a national multisite effort that focused on improving the health of eligible union members and retirees at high risk of developing asbestos-related disease. The asbestos screening and education programs were made available to "high-risk," asbestos-exposed local union members through the efforts of a number of international unions, including the International Union of Elevator Constructors and the Laborers' International Union of North America--both affiliates of the Building and Construction Trades Department, AFL-CIO. Consultation and program assistance in developing and implementing these programs were provided by the Occupational Health Foundation, a labor-sponsored, nonprofit organization with a multidisciplinary safety and health staff. Program components included identification of "high-risk" individuals, notification of risk, education, medical screening, legal referral, and various support services. Community-based physicians and/or physician-staffed mobile testing units provided services on a contractual basis according to a standardized medical protocol. Between 1988 and 1991, 2,136 union members and retirees from 89 local unions affiliated with the Elevator Constructors or the Laborers were screened in 59 regional programs. A general description and historical perspective are offered concerning program implementation, integration into existing union infrastructures. Emphasis is placed on the role of the unions in advancing members' interests when dealing with the health and socioeconomic implications of asbestos-related disease.

In order to better characterize thermistors, a group of 405 bead-in-glass and disc thermistors were aged in constant temperature baths. Samples of 135 thermistors were aged in each of three constant temperature baths held at 0, 30, and 60 °C. Each sample was composed of 65 bead-in-glass and 70 disc thermistors which represented a total of six manufacturers and six resistance values. The thermistors were maintained at temperature for 550 to 770 days and their resistances and the bath temperatures were periodically monitored. Analysis of the data revealed systematic differences between bead-in-glass and disc thermistors upon ageing and indicated a dependence of ageing behavior on bath temperature and resistance value. Drift rates within groups of thermistors from each manufacturer were fairly uniform. Large initial changes in the drift rate for the disc thermistors at 30 and 60 °C (and to a much lesser extent in the bead-in-glass thermistors) require that thermistors for use at an accuracy level of a few tens of millikelvins be aged prior to use.

In response to a union request, a cancer screening program was conducted for the Pattern Makers' League of North America. Ten colon cancer cases were detected among the 1,465 white men screened with a flexible sigmoidoscope. The difficulties in obtaining appropriate "expected" numbers were that prevalent detectable preclinical colon cancer is not equivalent to incident disease, and the flexible sigmoidoscope yields results not directly comparable to those of the rigid sigmoidoscope used previously. The "expected" number of cancers was obtained by using an independent estimate of 5 years for the mean duration of the detectable preclinical phase. This implied that the expected number of colon cancer cases should be based on the age-specific incident rates among white men in the next-older 5-year age group and that the annual expected number should be multiplied by five. Therefore, the ten observed cases of colon malignancies represented an approximately threefold increase. For invasive cancer only, there was a slightly less than twofold cancer increase. Fifteen percent of the men had one or more colorectal polyps.

In 1980, the Workers' Institute for Safety and Health began a demonstration project designed to develop a model program of community-based intervention in three cohorts with different workplace exposures and target cancer sites. Program components included identification, notification, medical surveillance, education, social support services (eg, psychosocial, legal, financial, etc), and evaluation. The three cohorts included the Augusta cohort, a group at risk for bladder cancer due to workplace exposure to beta-naphthylamine; the Port Allegany cohort, a group at high risk of cancer associated with a workplace exposure to asbestos; and the Pattern Makers cohort, a group shown to be at increased risk of colorectal cancer. Together, these three projects give a cross-sectional view of possible approaches to educational and medical intervention strategies in diverse situations.

Distributions of nine clinical chemistry determinations (serum bilirubin, globulin, creatinine, thyroxine, alkaline phosphatase, hematocrit, aspartate aminotransferase, uric acid, and plasma glucose) were assessed for 1,605 schoolchildren aged 6 to 17 years, in the Cincinati Lipid Research Clinic's Princeton School District study. Nine hundred and sixteen children were randomly recalled, and 689 were recalled by virtue of elevated (top decile) plasma cholesterol or triglyceride or both. For each clinical chemistry measurement, the following factors were considered: random and hyperlipidemic recall groups, age, sex, and race. The data were arrayed to provide the fifth percentile, the median, and the ninety-fifth percentile levels, as well as the 90% confidence interval of about the fifth and ninety-fifth percentile estimates. These data allow black-white age and sex, and normal-hyperlipidemic comparisons of commonly measured clinical chemistry determinations among a large population of children. This study also provides, for the methods used, accurate estimations of age-, sex-, race-, and recall group-specific percentile distributions for selected clinical chemistry determinations for children.

Fecal Hemoccult testing and flexible sigmoidoscopy have been proposed as means of screening for colorectal cancer in the general population, as well as in identified high-risk groups. A colorectal cancer screening program was conducted for the Pattern Makers' League of North America. A total of 1,473 white males were screened with fecal Hemoccult testing and flexible sigmoidoscopy during the period 1981 to 1983. The fecal Hemoccult test after diet restriction was positive in 38 workers (2.6%). Among 12 colorectal cancers, including in situ cases, only three were positive by this test. The sensitivity of this test for picking up cancer is only 25%. The positive predictive value was 7.9%. It is concluded that the Hemoccult test for the detection of colorectal cancer and polyps is not a valuable tool because of low sensitivity, whereas flexible sigmoidoscopy has a significant role in colorectal cancer screening of an asymptomatic population at risk.

Interrelationships between clinical chemistry tests (hepatic, renal, and endocrine systems) and lipids-lipoproteins were assessed in 1605 schoolchildren ages 6-17; 916 were randomly selected and 689 selected because of hypercholesterolemia/hypertriglyceridemia from the Cincinnati Lipid Research Clinic's Princeton School study. The clinical chemistry measurements most consistently and uniformly rated to lipids and lipoproteins were plasma glucose (GLU), uric acid (UA), serum glutamic oxaloacetic transaminase (SGOT) and hematocrit (HEMO). These relationships were similar quantitatively and qualitatively in 6-11-yr-old and 12-17-yr-old children in both the random and the hyperlipidemic recall groups. The most consistent relationship was a positive one between glucose and triglyceride (TG) and very low density lipoprotein cholesterol (C-VLDL). A second, highly consistent, relationship pattern included an inverse correlation between serum UA and high density lipoprotein cholesterol (C-HDL)), and a positive UA-C-VLDL relationship; both were seen in 12-17-yr-old children. Hematocrit was positively associated with TG; SGOT was positively associated with total cholesterol and C-HDL. Many of these relationships, particularly those for plasma GLU and UA, presage relationships observed in normal and hyperlipoproteinemic adults, and may allow a better understanding of the physiology and pathophysiology of lipid and lipoprotein levels.