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Introduction Teachers are a high-risk group for the development of vocal dysfunction, as they use voice extensively in their profession. Objective To know the prevalence and risk factors associated with voice strain in teachers. Methods A cross-sectional study was conducted among schoolteachers in Chitwan, Nepal. The Voice Handicap Index questionnaire was used as a survey tool. Result A total of 315 teachers were enrolled in the study. The mean age of the participants was of 36.7 years. Teachers from public schools, primary grade classes, > 50 pupils in the classroom, > 24 hours of classes per week, dust in class, and recurrent tonsil problems were associated with various degrees of vocal handicap. Conclusion There is a high prevalence of voice disorder among teachers. A holistic approach, which includes teacher education regarding voice care during their work and management of their voice handicap by taking into consideration different risk factors, must be adopted.
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The earth is warming, and the frequency of extreme weather events have been rapidly growing globally with unprecedented consequences to farming communities. In principle, weather and climate information services (WCIS) can help farmers better manage their activities and farm level outcomes by supporting their decision-making with relevant and usable information to address the potential impacts of expected changing climate conditions. But, in practice, can the availability and use of WCIS help improve agricultural outcomes given the weather and climate related uncertainties? To understand the use and impact of WCIS in the cotton-wheat cropping areas of Pakistan, we conducted a multistage stratified clustered random sample of 612 farm households in the provinces of Punjab and Sindh. Over 55% of the farm households in the sample indicated that they used WCIS provided by the Pakistan Meteorological Department and other sources for making their agricultural decisions. Our analysis, however, suggests that the impact of using WCIS on major farm outcomes (i.e. farm revenue, costs, profits, and input usage) is not statistically significant when compared with those farm households not using WCIS (null result). This result is robust to different estimation techniques (i.e. ordinary least squares, instrumental variable approach, and propensity score matching method). From the focus group discussions, we gathered that farmers perceived WCIS as less reliable, often unclear, and difficult to understand as this information is not translated and transmitted in local languages. Addressing these issues can help reduce the impact of climate and weather variability on farm outcomes in those provinces as well as in Pakistan more generally. Our study suggests that, under uncertainty, emphasis should be on WCIS that farmers can rely on for making farming related decisions.
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INTRODUCTION: Lemierre syndrome is a serious condition that associates oropharyngeal infection and thrombosis of the internal jugular vein (IJV) with subsequent distant septic emboli, most frequently in the lungs. CASE PRESENTATION: A 70-year-old female with retropharyngeal abscess developed features of Lemierre syndrome. The condition was managed with serial aspiration of the abscess and prolonged usage of intravenous antibiotics. DISCUSSION: Lemierre syndrome is most frequently caused by the anaerobic bacterium, Fusobacterium necrophorum. Although rare, there is evidence of a resurgence in the condition in recent years, most probably due to reduced use of antibiotic therapy for sore throats. Although there is a characteristic clinical picture, many clinicians are unaware of this condition, leading to delayed diagnosis with potentially fatal consequences. CONCLUSION: Early diagnosis of this condition and prompt treatment with intravenous broad spectrum antibiotics results in a complete resolution of this condition. Surgery is indicated in the case of abscess formation.
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To date, regulatory pesticide risk assessments have relied on the honey bee (Apis mellifera L.) (Hymenoptera: Apidae) as a surrogate test species for estimating the risk of pesticide exposure to all bee species. However, honey bees and non-Apis bees may differ in their susceptibility and exposure to pesticides. In 2017, a workshop ('Pesticide Exposure Assessment Paradigm for Non-Apis Bees') was held to assess if honey bee risk assessment frameworks are reflective of non-Apis bee pesticide exposure. In this article, we summarize the workshop discussions on bumble bees (Bombus spp.). We review the life history and foraging behavior of bumble bees and honey bees and discuss how these traits may influence routes and levels of exposure for both taxa. Overall, the major pesticide exposure routes for bumble bees and honey bees are similar; however, bumble bees face additional exposure routes (direct exposure of foraging queens and exposure of larvae and adults to soil residues). Furthermore, bumble bees may receive comparatively higher pesticide doses via contact or oral exposure. We conclude that honey bee pesticide risk assessments may not always be protective of bumble bees, especially queens, in terms of exposure. Data needed to reliably quantify pesticide exposure for bumble bees (e.g., food consumption rates, soil residue levels) are lacking. Addressing these knowledge gaps will be crucial before bumble bee exposure can be incorporated into the pesticide risk assessment process. Because bumble bees exhibit appreciable interspecific variation in colony and behavioral characteristics, data relevant to pesticide exposure should be generated for multiple species.
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Abejas , Exposición a Riesgos Ambientales , Plaguicidas , Animales , Conducta Animal , Femenino , Larva , Medición de RiesgoRESUMEN
A semifield study to assess the effects of iprodione on honeybees at label use rates was conducted on a bloom mustard crop. The present study followed the Organisation for Economic Co-operation and Development guideline 75 tunnel test and consisted of 3 groups: the iprodione-treated group, the untreated control group, and the toxic reference item group. In addition to the tunnels used for biological assessments, a tunnel was set up in the treatment and control groups to determine the level of residues in flowers, nectar, and pollen. The major endpoints to assess the effects of the application of iprodione were mortality, flight intensity, behavior, condition of the colonies, and development of the brood. Residue analysis showed that honeybees were exposed to significant residues of iprodione. However, no adverse effects were observed on overall mortality, flight intensity, behavior, or brood development of honeybees compared to control. It is concluded that iprodione does not adversely affect the health of honeybees when applied in agriculture at commercially relevant rates in a worst-case exposure scenario. Environ Toxicol Chem 2018;37:3086-3094. © 2018 SETAC.
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Aminoimidazol Carboxamida/análogos & derivados , Abejas/crecimiento & desarrollo , Conducta Animal/efectos de los fármacos , Flores/fisiología , Fungicidas Industriales/toxicidad , Hidantoínas/toxicidad , Planta de la Mostaza/fisiología , Hojas de la Planta/efectos de los fármacos , Aminoimidazol Carboxamida/toxicidad , Animales , Abejas/efectos de los fármacos , Vuelo Animal/efectos de los fármacos , Planta de la Mostaza/efectos de los fármacos , Néctar de las Plantas/química , Polen/química , Análisis de SupervivenciaRESUMEN
The Double Mountain Fork Brazos River (Texas, USA) consists of North (NF) and South Forks (SF). The NF receives urban runoff and twice-reclaimed wastewater effluent, whereas the SF flows through primarily rural areas. The objective of this study was to determine and compare associations between standard water quality variables and ichthyotoxicity at a landscape scale that included urban (NF) and rural (SF) sites. Five NF and three SF sites were sampled quarterly from March 2008 to March 2009 for specific conductance, salinity, hardness, pH, temperature, and turbidity; and a zebrafish (Danio rerio) embryo bioassay was used to determine ichthyotoxicity. Metal and nutrient concentrations at all sites were also measured in addition to standard water quality variables in spring 2009. Principal component analyses identified hardness, specific conductance, and salinity as the water variables that best differentiate the urban NF (higher levels) from rural SF habitat. Nutrient levels were also higher in the NF, but no landscape scale patterns in metal concentrations were observed. Ichthyotoxicity was generally higher in NF water especially in winter, and multiple regression analyses suggested a positive association between water hardness and ichthyotoxicity. To test for the potential influence of the toxic golden alga (Prymnesium parvum) on overall ichthyotoxicity, a cofactor known to enhance golden alga toxin activity was used in the bioassays. Golden alga ichthyotoxicity was detected in the NF but not the SF, suggesting golden alga may have contributed to overall ichthyotoxicity in the urban but not in the rural system. In conclusion, the physicochemistry of the urban-influenced NF water was conducive to the expression of ichthyotoxicity and also point to water hardness as a novel factor influencing golden alga ichthyotoxicity in surface waters.
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Bioensayo , Monitoreo del Ambiente , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/toxicidad , Animales , Ciudades , Ríos , Planificación Social , Texas , Factores de Tiempo , Pez Cebra/embriologíaRESUMEN
To assess interaction effects between cadmium (Cd, a putative xenoestrogen) and estradiol-17beta (E(2)) on sex differentiation and metamorphosis, Xenopus laevis were exposed to solvent-control (0.005% ethanol), Cd (10microgL(-1)), E(2) (1microgL(-1)), or Cd and E(2) (Cd+E(2)) in FETAX medium from fertilization to 75d postfertilization. Each treatment was applied to four aquaria, each with 30 fertilized eggs. Mortality was recorded and animals were sampled as they completed metamorphosis (Nieuwkoop and Faber stage 66). Gonadal sex of individuals (including >or= tadpoles NF stage 55 at day 75) was determined gross-morphologically and used to compute sex ratios. Time course and percent completion of metamorphosis, snout-vent length (SVL), hindlimb length (HLL) and weight were analyzed for each gender separately. Survival rates did not differ among treatments. The E(2) and Cd+E(2) treatments significantly skewed sex ratios towards females; however, no sex-ratio differences were observed between the control and Cd treatments or between the E(2) and Cd+E(2) treatments. Time course of metamorphosis was generally delayed and percent completion of metamorphosis was generally reduced in males and females exposed to Cd, E(2) or their combination compared to control animals. In males, but not females, the effect of Cd+E(2) was greater than that of individual chemicals. Weight at completion of metamorphosis was reduced only in females and only by the Cd+E(2) treatment. In conclusion, although Cd at an environmentally relevant concentration did not exhibit direct or indirect feminizing effects in Xenopus tadpoles, the metal and E(2) both had similar inhibitory effects on metamorphosis that were of greater magnitude in males than females.
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Cadmio/toxicidad , Estradiol/toxicidad , Gónadas/anatomía & histología , Metamorfosis Biológica/fisiología , Contaminantes Químicos del Agua/toxicidad , Animales , Embrión no Mamífero , Femenino , Gónadas/efectos de los fármacos , Masculino , Metamorfosis Biológica/efectos de los fármacos , Diferenciación Sexual , Xenopus laevis/metabolismoRESUMEN
Xenopus laevis larvae were exposed to cadmium (Cd) at 0, 1, 8, 85 or 860microgL(-1) in FETAX medium from 0 to 86d postfertilization. Premetamorphic tadpoles were sampled on day 31; pre and prometamorphic tadpoles on day 49; and frogs (NF stage 66) between days 50 and 86. Survival, snout-vent length (SVL), tail length, total length, hindlimb length (HLL), initiation of metamorphic climax, size at and completion of metamorphosis, and gonadal condition and sex ratio (assessed histologically) were determined. Survival was unaffected by Cd until day 49, but increased mortality was observed after day 49 at 860microgCdL(-1). On day 31, when tadpoles were in early premetamorphosis, inhibitory effects on tadpole growth were observed only at 860microgCdL(-1). On day 49, when most tadpoles where in late premetamorphosis/early prometamorphosis, reductions in SVL, HLL and total length were observed at 8 and 860 but not 85microgL(-1), thus creating a U-shaped size distribution at 0-85microgCdL(-1). However, this U-shaped size pattern was not evident in postmetamorphic individuals. In fact, frog size at completion of metamorphosis was slightly smaller at 85microgCdL(-1)relative to control animals. These observations confirmed a recent report of a Cd concentration-dependent bimodal growth pattern in late-premetamorphic Xenopus tadpoles, but also showed that growth responses to varying Cd concentrations change with development. The fraction of animals initiating or completing metamorphosis during days 50-86 was reduced in a Cd concentration-dependent manner. Testicular histology and population sex ratios were unaffected by Cd suggesting that, unlike mammals, Cd is not strongly estrogenic in Xenopus tadpoles.
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Cadmio/toxicidad , Metamorfosis Biológica/efectos de los fármacos , Diferenciación Sexual/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Razón de Masculinidad , Xenopus laevisRESUMEN
Xenopus laevis were exposed to 0-855 microg cadmium (Cd)/l (measured concentrations) in FETAX medium from fertilization to 47 days postfertilization. Measurements included embryonic survival and, at 47 days, tadpole survival, snout-vent length, tail length, total length, hindlimb length, weight, Nieuwkoop-Faber (NF) stage of development, initiation of metamorphic climax (> or = NF 58), and thyroid follicle cell height. Embryonic and larval survival were unaffected by Cd. Relative to control tadpoles, reduced tail and total length were observed at 0.1- 8 and at 855 microg Cd/l; and reduced snout-vent length, hindlimb length, and weight were observed at 0.1-1 and at 855 microg Cd/l. Mean stage of development and rate of initiation of climax were unaffected by Cd at 0-84 microg/l; however, none of the tadpoles exposed to 855 microg Cd/l progressed beyond mid-premetamorphosis (NF 51). Thyroid glands with fully formed follicles were observed in all tadpoles > or = NF 49 examined. Follicle cell height was unaffected by Cd at 0-84 microg/l but it was reduced at 855 microg/l; in the latter, cell height was reduced even when compared with NF 49-51 tadpoles pooled from the 0 to 84 microg Cd/l groups. In conclusion, (1) Cd affected tadpole growth in a bimodal pattern with the first and second inhibitory modes at concentrations below and above 84 microg Cd/l, respectively; (2) exposure to high Cd concentrations (855 microg/l) reduced thyroid activity and arrested tadpole development at mid-premetamorphosis; and (3) unlike its effect on growth, Cd inhibited tadpole development and thyroid function in a seemingly monotonic pattern.
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Cadmio/toxicidad , Metamorfosis Biológica/efectos de los fármacos , Glándula Tiroides/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Cadmio/farmacocinética , Relación Dosis-Respuesta a Droga , Femenino , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Dosificación Letal Mediana , Masculino , Tasa de Supervivencia , Glándula Tiroides/patología , Glándula Tiroides/fisiología , Xenopus laevis/embriologíaRESUMEN
The purpose of this study was to determine if changes in colloidal thyroxine (T(4)) immunoreactivity can be used as a biomarker of perchlorate exposure in amphibian thyroid tissue. Larval African clawed frogs (Xenopus laevis) were exposed to 0, 1, 8, 93, and 1131 microg perchlorate/l for 38 and 69 days to cover the normal period of larval development and metamorphosis. The results of this study confirmed the presence of an immunoreactive colloidal T(4) ring in thyroid follicles of X. laevis and demonstrated that the intensity of this ring is reduced in a concentration-dependent manner by perchlorate exposure. The smallest effective concentration of perchlorate capable of significantly reducing colloidal T(4) ring intensity was 8 microg perchlorate/l. The intensity of the immunoreactive colloidal T(4) ring is a more sensitive biomarker of perchlorate exposure than changes in hind limb length, forelimb emergence, tail resorption, thyrocyte hypertrophy, or colloid depletion. We conclude that the colloidal T(4) ring can be used as a sensitive biomarker of perchlorate-induced thyroid disruption in amphibians.