We examined the effects of periodic access to a palatable, high sugar content food (candy) in 8 male baboons on the anorectic response to d-amphetamine, which increases dopamine, and dexfenfluramine, which increases serotonin. During candy access, up to 200 candies containing 75% of energy as sugar were available during the morning on Mondays, Wednesdays and Fridays; food pellets (19% of energy as sugar) were available in the afternoon and throughout the remaining days of the week. During candy access, baboons consumed a mean of 177 pieces of candy containing 696 kcal (2.91 MJ) in the morning compared to 44 food pellets and 150 kcal (0.63 MJ) in the morning on non-candy days. Food pellet intake was lower during candy access. Complete dose-response functions for the effects of the drugs on food pellet intake on days that candy was not available were determined before, during, and after the period of access to candy. Dexfenfluramine and amphetamine produced dose-dependent decreases in food pellet intake and increases in latency to eat food pellets before, during, and after candy access. During access to candy, the dose-response function for dexfenfluramine was shifted to the right indicating the development of tolerance, while that for amphetamine was shifted to the left indicating sensitization. Only the dose-response function for dexfenfluramine returned to baseline after candy access suggesting that the difference was specific to concurrent palatable food consumption. We hypothesize that tolerance to the effects of dexfenfluramine reflects a decrease in the satiating effect of serotonin release due to repeatedly eating large amounts of palatable food.
Food Intake; Baboon; Sugar; Satiation; Dexfenfluramine; Amphetamine; Tolerance; Sensitization
The visual half-field procedure was used to examine hemispheric asymmetries in meaning selection. Event-related potentials were recorded as participants decided if a lateralized ambiguous or unambiguous prime was related in meaning to a centrally-presented target. Prime-target pairs were preceded by a related or unrelated centrally-presented context word. To separate the effects of meaning frequency and associative strength, unambiguous words were paired with concordant weakly-related context words and strongly-related targets (e.g., taste-sweet-candy) that were similar in associative strength to discordant subordinate-related context words and dominant-related targets (e.g., river-bank-deposit) in the ambiguous condition. Context words and targets were reversed in a second experiment. In an unrelated (neutral) context, N400 responses were more positive than baseline (facilitated) in all ambiguous conditions except when subordinate targets were presented on left visual field-right hemisphere (LVF-RH) trials. Thus, in the absence of biasing context information, the hemispheres seem to be differentially affected by meaning frequency, with the left maintaining multiple meanings and the right selecting the dominant meaning. In the presence of discordant context information, N400 facilitation was absent in both visual fields, indicating that the contextually-consistent meaning of the ambiguous word had been selected. In contrast, N400 facilitation occurred in all of the unambiguous conditions; however, the left hemisphere (LH) showed less facilitation for the weakly-related target when a strongly-related context was presented. These findings indicate that both hemispheres use context to guide meaning selection, but that the LH is more likely to focus activation on a single, contextually-relevant sense.
Lexical Ambiguity; Cerebral Hemispheres; Context Effects; ERP; N400; LPC
This study examined how user characteristics affect drop-off detection with the long cane. A mixed-measures design with block randomization was used for the study, in which 32 visually impaired adults attempted to detect the drop-offs using different cane techniques. Younger cane users detected drop-offs significantly more reliably (mean +/− standard deviation = 74.2% +/− 11.2% of the time) than older cane users (60.9% +/− 10.8%), p = 0.009. The drop-off detection threshold of the younger participants (5.2 +/− 2.1 cm) was also statistically significantly smaller than that of the older participants (7.9 +/− 2.2 cm), p = 0.007. Those with early-onset visual impairment (78.0% +/− 9.0%) also detected drop-offs significantly more reliably than those with later-onset visual impairment (67.3% +/− 12.4%), p = 0.01. No interaction occurred between examined user characteristics (age and age at onset of visual impairment) and the type of cane technique used in drop-off detection. The findings of the study may help orientation and mobility specialists select appropriate cane techniques in accordance with the cane user’s age and onset of visual impairment.
age; blind; cane user; detection threshold; drop-off detection; long cane technique; older adults; onset of visual impairment; orientation and mobility; visually impaired
This study examined the effect of cane tips and cane techniques on drop-off detection with the long cane.
Blind pedestrians depend on a long cane to detect drop-offs. Missing a drop-off may result in falls or collision with moving vehicles in the street. Although cane tips appear to affect a cane user’s ability to detect drop-offs, few experimental studies have examined such effect.
A repeated-measures design with block randomization was used for the study. Participants were 17 adults who were legally blind and had no other disabilities. Participants attempted to detect the drop-offs of varied depths using different cane tips and cane techniques.
Drop-off detection rates were similar between the marshmallow tip (77.0%) and the marshmallow roller tip (79.4%) when both tips were used with the constant contact technique, p = .294. However, participants detected drop-offs at a significantly higher percentage when they used the constant contact technique with the marshmallow roller tip (79.4%) than when they used the two-point touch technique with the marshmallow tip (63.2%), p < .001.
The constant contact technique used with a marshmallow roller tip (perceived as a less advantageous tip) was more effective than the two-point touch technique used with a marshmallow tip (perceived as a more advantageous tip) in detecting drop-offs.
The findings of the study may help cane users and orientation and mobility specialists select appropriate cane techniques and cane tips in accordance with the cane user’s characteristics and the nature of the travel environment.
blind mobility; two-point touch; constant contact; marshmallow tip; roller tip; visually impaired
X-ray diffraction data have been collected from crystals of recombinant sugar cane phosphoribosylpyrophosphate synthase (PRS) and analysis has revealed its quaternary structure, localizing this PRS into the class of enzymes forming an hexameric oligomer of 223 kDa.
Phosphoribosylpyrophosphate synthases (PRS; EC 22.214.171.124) are enzymes that are of central importance in several metabolic pathways in all cells. The sugar cane PRS enzyme contains 328 amino acids with a molecular weight of 36.6 kDa and represents the first plant PRS to be crystallized, as well as the first phosphate-independent PRS to be studied in molecular detail. Sugar cane PRS was overexpressed in Escherichia coli, purified and crystallized using the hanging-drop vapour-diffusion method. Using X-ray diffraction experiments it was determined that the crystals belong to the orthorhombic system, with space group P21212 and unit-cell parameters a = 213.2, b = 152.6, c = 149.3 Å. The crystals diffract to a maximum resolution of 3.3 Å and a complete data set to 3.5 Å resolution was collected and analysed.
phosphoribosylpyrophosphate; PRPP synthase; sugar cane
At 14 months, children appear to struggle to apply their fairly well developed speech perception abilities to learning similar sounding words (e.g. bih/dih; Stager & Werker, 1997). However, variability in non-phonetic aspects of the training stimuli seems to aid word learning at this age. Extant theories of early word learning cannot account for this benefit of variability. We offer a simple explanation for this range of effects based on associative learning. Simulations suggest that if infants encode both non-contrastive information (e.g. cues to speaker voice) and meaningful linguistic cues (e.g. place of articulation or voicing), then associative learning mechanisms predict these variability effects in early word learning. Crucially, this means that despite the importance of task variables in predicting performance, this body of work shows that phonological categories are still developing in this age, and that the structure of non-informative cues has critical influences on word learning abilities.
associative learning; word learning; language development; switch task; phonological development; variability
False memories occur when individuals mistakenly report an event as having taken place when that event did not in fact occur. The DRM (Deese, 1959; Roediger & McDermott, 1995) paradigm provides an effective technique for creating and investigating false memories. In this paradigm participants study a list of words (e.g., SOUR, CANDY,…) that are highly associated to a non-presented critical item (e.g., SWEET). The study phase is followed by a test of memory for the study list words. Researchers typically find very high levels of false recall of the critical non-presented item. However, the likelihood of falsely remembering the non-presented critical items can be reduced by presenting studied associates visually rather than auditorally (e.g. Smith & Hunt, 1998). This is referred to as the modality effect in false memory. The current study investigated the role of resource availability in the expression of this modality effect in false recall. In Experiment 1 false recall was reduced in the visual study presentation condition relative to the auditory condition for participants with higher working memory capacity, but not for participants with lower working memory capacity. In Experiment 2 the effect of study modality on false recall was eliminated by the addition of a divided attention task at encoding. Both studies support the proposal that resource availability plays a role in the expression of the modality effect in the DRM paradigm (Smith, Lozito, & Bayen, 2005).
In the present study neurophysiological correlates related to mismatching information in lexical access were investigated with a fragment priming paradigm. Event-related brain potentials were recorded for written words following spoken word onsets that either matched (e.g., kan – Kante [Engl. edge]), partially mismatched (e.g., kan – Konto [Engl. account]), or were unrelated (e.g., kan – Zunge [Engl. tongue]). Previous psycholinguistic research postulated the activation of multiple words in the listeners' mental lexicon which compete for recognition. Accordingly, matching words were assumed to be strongly activated competitors, which inhibit less strongly activated partially mismatching words.
ERPs for matching and unrelated control words differed between 300 and 400 ms. Difference waves (unrelated control words – matching words) replicate a left-hemispheric P350 effect in this time window. Although smaller than for matching words, a P350 effect and behavioural facilitation was also found for partially mismatching words. Minimum norm solutions point to a left hemispheric centro-temporal source of the P350 effect in both conditions. The P350 is interpreted as a neurophysiological index for the activation of matching words in the listeners' mental lexicon. In contrast to the P350 and the behavioural responses, a brain potential ranging between 350 and 500 ms (N400) was found to be equally reduced for matching and partially mismatching words as compared to unrelated control words. This latter effect might be related to strategic mechanisms in the priming situation.
A left-hemispheric neuronal network engaged in lexical access appears to be gradually activated by matching and partially mismatching words. Results suggest that neural processing of matching words does not inhibit processing of partially mismatching words during early stages of lexical identification. Furthermore, the present results indicate that neurophysiological correlates observed in fragment priming reflect different aspects of target processing that are cumulated in behavioural responses. Particularly the left-hemispheric P350 difference potential appears to be closely related to fine-grained activation differences of modality-independent representations in the listeners' mental lexicon. This neurophysiological index might guide future studies aimed at investigating neural aspects of lexical access.
The purpose of this study was to determine the effects of total, chocolate, or sugar candy consumption on intakes of total energy, fat, and added sugars; diet quality; weight/adiposity parameters; and risk factors for cardiovascular disease in children 2–13 years of age (n=7,049) and adolescents 14–18 years (n=4,132) participating in the 1999–2004 National Health and Nutrition Examination Survey.
Twenty-four hour dietary recalls were used to determine intake. Diet quality was determined using the Healthy Eating Index-2005 (HEI-2005). Covariate-adjusted means, standard errors, and prevalence rates were determined for each candy consumption group. Odds ratios were used to determine the likelihood of associations with weight status and diet quality.
In younger children, total, chocolate, and sugar candy consumption was 11.4 g±1.61, 4.8 g±0.35, and 6.6 g±0.46, respectively. In adolescents, total, chocolate, and sugar candy consumption was 13.0 g±0.87, 7.0 g±0.56, and 5.9 g±0.56, respectively. Total candy consumers had higher intakes of total energy (2248.9 kcals±26.8 vs 1993.1 kcals±15.1, p<0.0001) and added sugars (27.7 g±0.44 vs 23.4 g±0.38, p<0.0001) than non-consumers. Mean HEI-2005 score was not different in total candy and sugar candy consumers as compared to non-consumers, but was significantly lower in chocolate candy consumers (46.7±0.8 vs 48.3±0.4, p=0.0337). Weight, body mass index (BMI), waist circumference, percentiles/z-score for weight-for-age and BMI-for-age were lower for candy consumers as compared to non-consumers. Candy consumers were 22 and 26%, respectively, less likely to be overweight and obese than non-candy consumers. Blood pressure, blood lipid levels, and cardiovascular risk factors were not different between total, chocolate, and sugar candy consumers and non-consumers (except that sugar candy consumers had lower C-reactive protein levels than non-consumers).
This study suggests that candy consumption did not adversely affect health risk markers in children and adolescents.
children; adolescents; candy; chocolate; sugar candy; added sugars; discretionary calories; nutrient intake; dietary adequacy; health risk factors; healthy eating index; NHANES
We examined the associations between sweets, sweetened and unsweetened beverages, and sugars and pancreatic cancer risk.
We conducted a population-based case–control study (532 cases, 1,701 controls) and used multivariate logistic regression models to calculate odds ratios (OR) and 95% confidence intervals (CI). Because associations were often different by sex, we present results for men and women combined and separately.
Among men, greater intakes of total and specific sweets were associated with pancreatic cancer risk (total sweets: OR = 1.9, 95% CI: 1.0, 3.6; sweet condiments: OR = 1.9, 95% CI: 1.2, 3.1; chocolate candy: OR = 2.4, 95% CI: 1.1, 5.0; other mixed candy bars: OR = 3.3, 95% CI: 1.5, 7.3 for 1 + servings/day versus none/rarely). Sweets were not consistently associated with risk among women. Sweetened beverages were not associated with increased pancreatic cancer risk. In contrast, low-calorie soft drinks were associated with increased risk among men only; while other low-/non-caloric beverages (e.g., coffee, tea, and water) were unassociated with risk. Of the three sugars assessed (lactose, fructose, and sucrose), only the milk sugar lactose was associated with pancreatic cancer risk (OR = 2.0, 95% CI: 1.5, 2.7 comparing extreme quartiles).
These results provide limited support for the hypothesis that sweets or sugars increase pancreatic cancer risk.
Pancreatic cancer; Epidemiology; Sweets; Beverages
Alcohol production at the laboratory scale from sugar cane pieces by the EX-FERM technique was studied with 37 strains of Saccharomyces spp. The EX-FERM process is novel in that it employs the simultaneous extraction and fermentation of the sucrose in a cane-water suspension. Two types of cane treatments were used: chips and shredded pith, either fresh or dried. A mother culture of the yeast was prepared in enriched cane juice and then added to the cane-water mixture. After static fermentation for 40 h at 30°C, the cane was removed, and fresh cane was added to the yeast-alcohol broth. After an additional 24 h, the cane was again removed and the liquor was analyzed. After the first 40-h cycle, sugar consumption was above 99% with 10 of the 37 yeast strains tested, and ethanol reached levels of 1.29 to 4.00 g per 100 ml, depending on the yeast strain. The final ethanol concentration reached 4.27 to 5.37 g per 100 ml, and sugar consumption was above 98% in three cases during a second EX-FERM cycle employing previously air-dried chips and pith. Product yields were within accepted values. Cane treatment did not appear to affect the results at this level.
There are many contributors to obesity, including excess consumption of “discretionary calories” (foods high in sugar and fat and low in essential nutrients), lack of fruit/vegetable consumption, and insufficient physical activity. This study contrasted physical activity, fruit/vegetable consumption, and discretionary calorie consumption from selected foods relative to the 2005 dietary guidelines.
We conducted a cross-sectional survey in 228 urban census tracts in Los Angeles County (LAC) and Southern Louisiana (SL) and estimated calories in the past 24 hours from fruit, vegetables, cookies, candy, salty snacks, sweetened soda, and alcohol among 2,767 participants.
The population-weighted mean daily intake of calories from candy, cookies, salty snacks, soda, and alcohol was 438 in LAC and 617 in SL. Alcohol comprised a small portion of the calories consumed. Reported discretionary calorie consumption from a small set of items exceeded guidelines by more than 60% in LAC and 120% in SL. In contrast, the mean consumption of fruit and vegetables fell 10% short in LAC and 20% in SL. There was significant heterogeneity in consumption of cookies, candy, salty snacks, and soda across income, gender, and race.
The overconsumption of discretionary calories was much greater than the underconsumption of fruit and vegetables. This finding suggests that unless the excessive consumption of salty snacks, cookies, candy, and sugar-sweetened beverages is curtailed, other interventions focusing on increasing physical activity and fruit and vegetable consumption will have a limited impact on obesity control. It may be politically more expedient to promote an increase in consumption of healthy items rather than a decrease in consumption of unhealthy items, but it may be far less effective.
Two retarded boys exhibited abnormally low rates of smiling. In Exp. I, the frequency of a boy's smiling was first increased with candy reinforcement, but the frequency of the response did not decrease when candy reinforcement was terminated. When the subject wore a sign designed to make social interactions contingent on not-smiling, the frequency of smiling decreased. The sign was then changed to make social interactions contingent on smiling and the rate of smiling increased. In Exp. II, a second boy initially never smiled. Establishment of a contingency for candy reinforcement did not increase this zero response rate. Instructing the child to smile initially increased smiling, but the instructions then became progressively more ineffective. Candy reinforcement increased the rate of smiling to a normal range, but the rate of the response promptly decreased when this reinforcement was discontinued. Continuous candy reinforcement was again employed to increase the response rate and then progressively leaner schedules of variable-ratio candy reinforcement were employed. Consequently, the rate of smiling did not decrease when candy reinforcement was again eliminated. Subsequently, signs were employed to regulate social interactions and the rate of smiling was shown to be controlled by these interactions serving as reinforcers.
The Indian herb Gymnema sylvestre has been used in traditional Ayurvedic medicine for 2000 years, most recently for the treatment of diabetes. Loose leaf Gymnema sylvestre can be prepared as a tea and will impair the ability to taste sugar by blocking sweet receptors on the tongue. This report describes a laboratory exercise easily applied to an undergraduate neuroscience course that can be used to illustrate the principles of gustatory sensation. Combined with a preceding lecture on the primary taste sensations, students experience and appreciate how the primary tastes are combined to produce overall taste. In addition, the exercises outlined here expand upon previously published demonstrations employing Gymnema sylvestre to include illustrations of the different sensory transduction mechanisms associated with each of the four or five primary taste modalities. Students compare their qualitative primary taste experiences to salt, sugar, aspartame, chocolate, and sweet-sour candy prior to and following exposure to Gymnema sylvestre. The herb’s impairment of sweet sensation is profound and dramatically alters the perception of sweetness in sugar, chocolate, and candy without altering the perception of the other primary tastes. The exercise has an indelible effect on students because the herb’s intense effect compels students to rely on their unique personal experiences to highlight the principles of gustatory sensation.
gustation; sensory transduction; taste; tongue
Recent research suggests that the left inferior frontal gyrus (LIFG) plays a role in selecting semantic information from among competing alternatives. A key question remains as to whether the LIFG is engaged by the selection of semantic information only or by increased semantic competition in and of itself, especially when such competition is implicit in nature. Ambiguous words presented in a lexical context provide a means of examining whether the LIFG is recruited under conditions when contextual cues constrain selection to only the meaning appropriate to the context (e.g., coin-mint-money) or under conditions of increased competition when contextual cues do not allow for the resolution to a particular meaning (e.g., candy-mint-money). In this event-related fMRI study, an implicit task was used in which subjects made lexical (i.e., word/nonword) decisions on the third stimulus of auditorily-presented triplets in conditions where the lexical context either promoted resolution toward a particular ambiguous word meaning or enhanced the competition among ambiguous word meanings. LIFG activation was observed when the context allowed for the resolution of competition and hence the selection of one meaning (e.g., coin-mint-money) but failed to emerge when competition between the meanings of an ambiguous word was unresolved by the context (e.g., candy-mint-money). In the latter case, there was a pattern of reduced activation in frontal, temporal and parietal areas. These findings demonstrate that selection or resolution of competition as opposed to increased semantic competition alone engages the LIFG. Moreover, they extend previous work in showing that the LIFG is recruited even in cases where the selection of meaning takes place implicitly.
fMRI; left inferior frontal gyrus; left superior temporal gyrus; semantic ambiguity; semantic competition; semantic selection
Functional magnetic resonance imaging (fMRI) was used to examine the neural correlates of semantic judgments to Chinese words in a group of 10–15 year old Chinese children. Two semantic tasks were used: visual–visual versus visual–auditory presentation. The first word was visually presented (i.e. character) and the second word was either visually or auditorily presented, and the participant had to determine if these two words were related in meaning. Different from English, Chinese has many homophones in which each spoken word corresponds to many characters. The visual–auditory task, therefore, required greater engagement of cognitive control for the participants to select a semantically appropriate answer for the second homophonic word. Weaker association pairs produced greater activation in the mid-ventral region of left inferior frontal gyrus (BA 45) for both tasks. However, this effect was stronger for the visual–auditory task than for the visual–visual task and this difference was stronger for older compared to younger children. The findings suggest greater involvement of semantic selection mechanisms in the cross-modal task requiring the access of the appropriate meaning of homophonic spoken words, especially for older children.
fMRI; Semantic; Visual; Auditory; Association strength; Age
Strengths and Difficulties Questionnaire (SDQ) is a brief behavioural screening questionnaire for children and teenagers aged 3 to 16 years. It is available in 66 languages, and gaining more popularity world wide. Chinese translation of SDQ is available and has been used in clinical practice and research. We undertook the exercise to back-translate the current Chinese translation and it showed a number of differences compared to the original English SDQ. The differences and concerns include: (1) the flow and grammar of Chinese translation as well as wrongly written Chinese characters; (2) translated words that have deviated from the original meaning; (3) significant numbers of wording that are somewhat different from the original English version; (4) addition of auxiliary verbs that do not exist in original English version; and (5) the current Chinese SDQ is a general questionnaire for all age groups that does not observe the differences of wording that exist in the English versions.
An accurate translated Chinese version is important for researchers, clinicians and educators who work in the Chinese communities. There is an urgent need to review the translation of the Chinese SDQ version before more studies use it in the field.
Excessive consumption of highly-palatable foods may contribute to the development of weight gain. Therefore medications that selectively suppress eating of such foods would be useful in clinical practice. We compared the effects of the glutamatergic antagonists memantine and MTEP to dexfenfluramine in baboons given periodic access to highly-palatable food and ad libutum access to a standard chow diet. Three days a week baboons received a sugar-coated candy during the first meal and standard diet chow pellets were available in subsequent meals. All baboons derived a greater amount of energy from the single candy meal than from the standard diet across an entire day. Pre-treatment with dexfenfluramine, memantine, and MTEP produced decreases in candy consumption without altering candy-seeking behaviour. At the same time, dexfenfluramine and memantine, but not MTEP, produced a decrease in seeking and consumption of standard chow pellets. Both memantine and MTEP are promising agents for the treatment of obesity.
Recent research into stuttering in English has shown that function word disfluency decreases with age whereas content words disfluency increases. Also function words that precede a content word are significantly more likely to be stuttered than those that follow content words (Au-Yeung, Howell and Pilgrim, 1998; Howell, Au-Yeung and Sackin, 1999). These studies have used the concept of the phonological word as a means of investigating these phenomena. Phonological words help to determine the position of function words relative to content words and to establish the origin of the patterns of disfluency with respect to these two word classes. The current investigation analysed German speech for similar patterns. German contains many long compound nouns; on this basis, German content words are more complex than English ones. Thus, the patterns of disfluency within phonological words may differ between German and English. Results indicated three main findings. Function words that occupy an early position in a PW have higher rates of disfluency than those that occur later in a PW, this being most apparent for the youngest speakers. Second, function words that precede the content word in a PW have higher rates of disfluency than those that follow the content word. Third, young speakers exhibit high rates of disfluency on function words, but this drops off with age and, correspondingly, disfluency rate on content words increases. The patterns within phonological words may be general to German and English and can be accounted for by the EXPLAN model, assuming lexical class operates equivalently across these languages or that lexical categories contain some common characteristic that is associated with fluency across the languages.
Stuttering; German; function and content words
Carbohydrates are nowadays a very competitive feedstock for the chemical industry because their availability is compatible with world-scale chemical production and their price, based on the carbon content, is comparable to that of petrochemicals. At the same time, demand is rising for biobased products. Brazilian sugar cane is a competitive feedstock source that is opening the door to a wide range of bio-based products. This essay begins with the importance of the feedstock for the chemical industry and discusses developments in sugar cane processing that lead to low cost feedstocks. Thus, sugar cane enables a new chemical industry, as it delivers a competitive raw material and a source of energy. As a result, sugar mills are being transformed into sustainable biorefineries that fully exploit the potential of sugar cane.
Aldicarb, 2-methyl-2-(methylthio)propionaldehyde-O-methylcarbamoyloxime, is an oxime carbamate insecticide manufactured by the Union Carbide Corporation and sold under the trade name Temik. It is a soil-applied systemic pesticide used against certain insects, mites, and nematodes, and is applied below the soil surface for absorption by plant roots. It is generally applied to the soil in the form of 5, 10, or 15% granules, and soil moisture is essential for the release of the toxicant. Uptake by plants is rapid. Aldicarb is currently registered for use on cotton, sugar beets, sugar cane (Louisiana only), potatoes, sweet potatoes, peanuts, oranges, pecans (Southeast only), dry beans, soybeans, and ornamental plants. Home and garden use is not permitted. Discovery of aldicarb and its oxidative sulfoxide and sulfone metabolites in well or ground water in Florida, Wisconsin, and New York, and accidental poisonings from ingesting contaminated watermelons and cucumbers in the South and West have spurred interest and concern about this pesticide. The primary mechanism of toxic action of aldicarb is cholinesterase inhibition. However, unlike the relatively irreversible anticholinesterase activity of the organophosphate pesticides, the carbamylation process which produces the anti-AChE action is quickly reversible. Aldicarb is readily absorbed through both the gut and the skin, but is rapidly metabolized and excreted in the urine almost completely within 24 hr. Although it is acutely toxic to humans and laboratory animals, aldicarb is not known to be carcinogenic, teratogenic, conclusively mutagenic, or to produce other long-term adverse health effects. In cases of accidental poisoning, the cholinergic symptoms have generally subsided within 6 hr, with no side effects or complications.
Fifteen-day-old variety NA 56-79 sugar cane seedlings were inoculated with Azospirillum brasilense and Glomus intrarradix. This article aims at examining changes in sugar cane root seedlings inoculated with Glomus intrarradix and Azospirillum brasilense, the increase in microbial biomass and the acetylene reduction process as well. The internal root colonization was studied 20 days after inoculation using scanning and a transmission electron microscope. Both microorganisms entered the sugar cane root through the emergent lateral roots. The microorganisms were capable of coexisting both intra and intercellularly, producing changes in the cell wall, thus allowing colonization and interaction between the organisms. These changes increased the number of microorganisms inside the root as well as acetylene nitrogen reduction. Sugar cane plant biomass increased with joint-inoculation. The number of endophytic microorganisms and nitrogen fixing activity increased when they were colonized by Azospirillum and Glomus together.
Acetylene reduction; Azospirillum brasilense; Glomus intrarradix; Microbial biomass
Reversible thermal injury to the esophagus as the result of drinking hot liquids has been reported to generate alternating white and red linear mucosal bands, somewhat reminiscent of a candy cane. This phenomenon is associated with chest pain, dysphagia, odynophagia, and epigastric pain.
Here, we report a case of thermal injury to the esophageal and oral cavity due to the drinking of hot tea, including odynophagia and dysphagia.
A 69-year-old man was referred due to a difficulty in swallowing which had begun a week prior to referral. The patient, at the time of admission, was unable to swallow even liquids. He had recently suffered from hiccups, and had consumed five cups of hot adlay tea one week prior to admission, as a folk remedy for the hiccups. Upon physical examination, the patient's oral cavity evidenced mucosal erosion, hyperemia, and mucosa covered by a whitish pseudomembrane. Nonspecific findings were detected on the laboratory and radiological exams. Upper endoscopy revealed diffuse hyperemia, and erosions with thick and whitish pseudomembraneous mucosa on the entire esophagus. The stomach and duodenum appeared normal. We diagnosed the patient with thermal esophageal injury inflicted by the hot tea. He was treated with pantoprazole, 40 mg/day, for 14 days, and evidenced significant clinical and endoscopic improvement.
Thermal injury; Tea; Dysphagia
Davies, C. T. M. (1973).British Journal of Industrial Medicine,30, 146-154. Relationship of maximum aerobic power output to productivity and absenteeism of East African sugar cane workers. The relationship of the physiological responses to laboratory exercise on an upright bicycle ergometer and predicted maximum aerobic power output (V̇O2max) to daily and season output has been investigated in 78 cane cutters aged 18 to 50 years working on the Kilombero sugar estate, Tanzania.
The results showed that the (V̇O2max) was independent of absolute productivity in terms of kilotons of cane cut per season but positively correlated (r = + 0·46) with daily output. There was a small but significant (r = - 0·32, P < 0·001) negative association of V̇O2max with the number of days that an individual voluntarily absented himself from the cane fields. The importance of these findings to the selection and training of personnel for the cane-cutting industry are discussed. It was suggested that the industry might consider the introduction of a simple exercise (step) test together with a medical examination and simple anthropometric measurements at the time of recruitment of workers at the beginning of the season.
Background. Gum arabic is a potential sensitizer in food industry. Methods. We examined 11 candy factory workers referred to examinations due to respiratory and skin symptoms paying attention to exposure and sensitization to gum arabic. Skin tests, pulmonary function tests, and respiratory provocation tests were carried out as indicated by the symptoms and findings. Results. Occupational asthma, caused by gum arabic was diagnosed in 4/11 candy factory workers and two of them had also occupational contact urticaria and one had occupational rhinitis. One of them had oral symptoms associated with ingestion of products containing gum arabic. Conclusions. Airborne exposure to gum arabic may cause sensitization leading to allergic rhinitis, asthma, and urticaria.