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1.
J Anim Ecol ; 91(2): 308-319, 2022 02.
Article in English | MEDLINE | ID: mdl-34704260

ABSTRACT

Compensatory recruitment is a key demographic mechanism that has allowed the coexistence of populations of susceptible amphibians with Batrachochytrium dendrobatidis (Bd), a fungus causing one of the most devastating emerging infectious disease ever recorded among vertebrates. However, the underlying processes (e.g. density-dependent increase in survival at early life stages, change in reproductive traits) as well as the level of interpopulation variation in this response are poorly known. We explore potential mechanisms of compensatory recruitment in response to Bd infection by taking advantage of an amphibian system where male reproductive traits are easy to quantify in free-living populations. The Southern Darwin's frog Rhinoderma darwinii is a vocal sac-brooding species that exhibits a high susceptibility to lethal Bd infection. Using a 7-year capture-recapture study at four populations with contrasting Bd infection status (one high prevalence, one low prevalence and two Bd-free populations), we evaluated whether Bd-positive populations exhibited a higher adult recruitment and a higher male reproductive effort than Bd-negative populations. We also estimated population growth rates to explore whether recruitment compensated for the negative impacts of Bd on the survival of adults. In addition, we evaluated a potential demographic signal of compensatory recruitment (i.e. positive relationship between the proportion of juveniles and Bd prevalence) in response to Bd infection using raw count data from 13 R. darwinii populations. The high Bd prevalence population exhibited the highest male reproductive effort and the highest recruitment among the four monitored populations. This led to a growing population during the study period despite high mortality of adult hosts. In contrast, males from the population with low Bd prevalence had a low reproductive effort and this population, which had the lowest adult recruitment, was declining during the study period despite adults having a higher survival in comparison to the high Bd prevalence population. We also found a demographic signal of compensatory recruitment in response to Bd infection in our broader analysis of 13 R. darwinii populations. Our study underlines the importance of interpopulation variation in life-history strategies on the fate of host populations after infectious disease emergence. Our results also suggest that an increase in reproductive effort can be one of the processes underlying compensatory recruitment in populations of Bd-susceptible amphibians.


Subject(s)
Chytridiomycota , Mycoses , Amphibians/microbiology , Animals , Anura/microbiology , Chytridiomycota/physiology , Male , Mycoses/epidemiology , Mycoses/microbiology , Mycoses/veterinary , Population Dynamics , Reproduction
2.
PLoS One ; 12(5): e0177086, 2017.
Article in English | MEDLINE | ID: mdl-28481921

ABSTRACT

This study investigated the influence of sodium restriction and antihypertensive drugs on atherogenesis utilizing hypertensive (H) low-density lipoprotein-receptor knockout mice treated or not with losartan (Los) or hydralazine (Hyd) and fed low-sodium (LS) or normal-sodium (NS) chow. Despite reducing the blood pressure (BP) of H-LS mice, the LS diet caused arterial lipid infiltration due to increased plasma total cholesterol (TC) and triglycerides (TG). Los and Hyd reduced the BP of H-LS mice, and Los effectively prevented arterial injury, likely by reducing plasma TG and nonesterified fatty acids. Aortic lipid infiltration was lower in Los-treated H-LS mice (H-LS+Los) than in normotensive (N)-LS and H-LS mice. Aortic angiotensin II type 1 (AT1) receptor content was greater in H-NS than H-LS mice and in H-LS+Hyd than H-LS+Los mice. Carboxymethyl-lysine (CML) and receptor for advanced glycation end products (RAGE) immunostaining was greater in H-LS than H-NS mice. CML and RAGE levels were lower in LS animals treated with antihypertensive drugs, and Hyd enhanced the AT1 receptor level. Hyd also increased the gene expression of F4/80 but not tumor necrosis factor-α, interleukin (IL)-1ß, IL-6, IL-10, intercellular adhesion molecule-1 or cluster of differentiation 66. The novelty of the current study is that in a murine model of simultaneous hypertension and hyperlipidemia, the pleiotropic effect of chronic, severe sodium restriction elicited aortic damage even with reduced BP. These negative effects on the arterial wall were reduced by AT1 receptor antagonism, demonstrating the influence of angiotensin II in atherogenesis induced by a severely LS diet.


Subject(s)
Atherosclerosis/etiology , Blood Pressure , Diet, Sodium-Restricted , Hyperlipidemias/complications , Hypertension/prevention & control , Animals , Hypertension/complications , Mice , Mice, Knockout , Receptors, LDL/genetics
3.
Cir Cir ; 85(3): 225-233, 2017.
Article in Spanish | MEDLINE | ID: mdl-27745883

ABSTRACT

BACKGROUND: Tinnitus is defined as the conscious perception of a sensation of sound that occurs in the absence of an external stimulus. This audiological symptom affects 7% to 19% of the adult population. The aim of this study is to describe the associated comorbidities present in patients with tinnitus usingjoint and conditional probability analysis. PATIENTS: Patients of both genders, diagnosed with unilateral or bilateral tinnitus, aged between 20 and 45 years, and had a full computerised medical record, were selected. METHODS: Study groups were formed on the basis of the following clinical aspects: 1) audiological findings; 2) vestibular findings; 3) comorbidities such as, temporomandibular dysfunction, tubal dysfunction, otosclerosis and, 4) triggering factors of tinnitus noise exposure, respiratory tract infection, use of ototoxic and/or drugs. RESULTS: Of the patients with tinnitus, 27 (65%) reported hearing loss, 11 (26.19%) temporomandibular dysfunction, and 11 (26.19%) with vestibular disorders. When performing the joint probability analysis, it was found that the probability that a patient with tinnitus having hearing loss was 2742 0.65, and 2042 0.47 for bilateral type. The result for P (A ∩ B)=30%. Bayes' theorem P (AiB) = P(Ai∩B)P(B) was used, and various probabilities were calculated. Therefore, in patients with temporomandibulardysfunction and vestibular disorders, a posterior probability of P (Aі/B)=31.44% was calculated. CONCLUSIONS: Consideration should be given to the joint and conditional probability approach as tools for the study of different pathologies.


Subject(s)
Tinnitus/epidemiology , Academies and Institutes , Adult , Bayes Theorem , Comorbidity , Female , Hearing Loss/epidemiology , Humans , Male , Mexico , Middle Aged , Noise/adverse effects , Otosclerosis/epidemiology , Temporomandibular Joint Disorders/epidemiology , Tinnitus/etiology , Vestibular Diseases/epidemiology , Young Adult
4.
J Otolaryngol Head Neck Surg ; 42: 55, 2013 Nov 26.
Article in English | MEDLINE | ID: mdl-24279682

ABSTRACT

BACKGROUND: Dizziness-vertigo is common in adults, but clinical providers may rarely diagnose vestibular impairment and referral could be delayed. To assess neurotology symptoms (including triggers) reported by patients with peripheral vestibular disease, during the year just before their referral to vestibular evaluation. METHODS: 282 patients with peripheral vestibular disease and 282 control subjects accepted to participate. They had no middle ear, retinal, neurological, psychiatric, autoimmune or autonomic disorders. They reported their symptoms by a standardized questionnaire along with their anxiety/depression symptoms. RESULTS: Patients were referred after months or years from the onset of their symptoms, 24% of them reported frequent falls with a long clinical evolution; 10% of them reported no vertigo but instability related to specific triggers; 86% patients and 12% control subjects reported instability when moving the head rapidly and 79% patients and 6% control subjects reported instability when changing posture. Seven out of the 9 symptoms explored by the questionnaire allowed the correct classification of circa 95% of the participants (Discriminant function analysis, p < 0.001). High blood pressure, dyslipidemia and anxiety/depression symptoms showed a mild correlation with the total score of symptoms (multiple R2 =0.18, p < 0.001). CONCLUSIONS: Late referral to vestibular evaluation may underlie a history of frequent falls; some patients may not report vertigo, but instability related to specific triggers, which could be useful to prompt vestibular evaluation. High blood pressure, dyslipidemia and anxiety/depression symptoms may have a mild influence on the report of symptoms of vestibular disease in both, patients and control subjects.


Subject(s)
Vestibular Diseases/diagnosis , Accidental Falls/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Benign Paroxysmal Positional Vertigo , Dizziness/etiology , Female , Humans , Male , Meniere Disease/diagnosis , Middle Aged , Multivariate Analysis , Referral and Consultation , Vertigo/diagnosis , Vertigo/etiology , Vestibular Diseases/complications , Young Adult
5.
Prog. obstet. ginecol. (Ed. impr.) ; 51(11): 656-664, nov. 2008. ilus, tab
Article in Es | IBECS | ID: ibc-68584

ABSTRACT

Objetivo: Conocer la tasa de mortalidad fetal intermedia (TMFI) y tardía (TMFT) en la población gestante atendida en un período de 10 años en el Hospital Clínico de la Universidad de Chile. Material y métodos: Estudio descriptivo donde se analizaron los datos de la muertes fetales ocurridas a partir de las 22 semanas o 500 g de peso entre 1994 y 2004. Resultados: La TMFI fue de 1,43/1000 nacidos vivos (NV) y la TMFT fue de 4,28/1000 NV. Las principales etiologías asociadas según su prevalencia fueron: enfermedad materna, patología de anexos ovulares, malformaciones congénitas e hipoxia (el 39, el 36, el 19 y el 10%, respectivamente). Conclusión: La TMFT en este estudio es similar a la nacional (4,3/1000 NV


Objetive: To know Fetal Mortality Rate during ten years in the Hospital Clínico Universidad de Chile. Material and methods: Intermedial and Late Fetal Mortality Rate (IFMR­LFMR) for Hospital Clínico Universidad de Chile for the period between 1994 to 2004 were analyzed. The information was obtained from clinical date. Results: IFMR: 1,43/1000, LFMR 4,28/1000. Causes of intrauterine fetal death were: maternal diseases (39%), placental and funicular accident (36%), structural abnormality (19%) and hypoxia (10%). Conclusion: LFMR in this study is the same that the Chilean reality (4,3/1000) (AU)


Subject(s)
Humans , Female , Pregnancy , Fetal Death/epidemiology , Indicators of Morbidity and Mortality , Risk Factors , Gestational Age , Maternal Age
6.
J Vestib Res ; 18(2-3): 129-37, 2008.
Article in English | MEDLINE | ID: mdl-19126983

ABSTRACT

To compare the frequency of symptoms of detachment from the self or from the environment (DD) in patients with an acquired deficiency of the special senses, a questionnaire for DD symptoms [12] and the GHQ12 questionnaire for common mental disorders [16] were auto-administered to patients with hearing-loss (N = 40), peripheral vestibular disease (N = 40) or bilateral retinal disease (N = 40), and to 80 healthy subjects. Patients with retinal disease and patients with vestibular disease reported DD symptoms more frequently & severe than patients with hearing loss and healthy subjects. DD scores were related to the GHQ12 scores and to the type of sensory dysfunction. DD symptoms are more frequent & severe in patients with an acquired deficiency of the special senses, associated to symptoms of common mental disorders.


Subject(s)
Affect , Cost of Illness , Depersonalization/complications , Self Concept , Sensation Disorders/psychology , Adaptation, Psychological , Adult , Aged , Case-Control Studies , Cross-Sectional Studies , Depersonalization/psychology , Emotions , Female , Hearing Loss/complications , Hearing Loss/psychology , Humans , Male , Mental Disorders/complications , Mental Disorders/psychology , Middle Aged , Reference Values , Retinal Diseases/complications , Retinal Diseases/psychology , Self-Assessment , Sensation Disorders/complications , Severity of Illness Index , Social Identification , Vestibular Diseases/complications , Vestibular Diseases/psychology , Young Adult
7.
Psicol. rev ; (8): 23-40, 1999.
Article in Portuguese | LILACS | ID: lil-288312

ABSTRACT

Quinhentos e noventa e cinco estudantes de escolas públicas de bairros de classe média da cidade de Säo Paulo responderam a um questionário de autopreenchimento com questões sobre o uso de inalantes e sobre sua opiniäo a respeito das pessoas que usam essas substâncias. O questionário também incluía itens sobre temperamento, extraídos do Trídimensional Personalíty Questíonnaíre (TPQ). O uso na vida foi relatado por 16,3 por cento dos sujeitos, o uso freqüente por O,7 por cento e o uso pesado por O,8 por cento. As substâncias mais citadas foram o lança-perfume e a acetona. O usuário freqüente foi considerado "uma pessoa doente, que precisa de ajuda', tanto por usuários como por näo-usuários; já o usuário ocasional foi considerado "uma pessoa como outra qualquer" pelos usuários e "uma pessoa fraca, sem força de vontade" pelos näo-usuários. Os usuários obtiveram pontuações mais elevadas do que os näo-usuários na escala de busca de novidades do TPQ. Concluiu-se que os inalantes säo usados por uma parcela significativa de jovens de classe média, o que revela a necessidade do desenvolvimento de trabalhos preventivos específicos para o uso dessas drogas, que levem em conta os fatores de risco de ordem social e psicológica para o uso de inalantes nessa populaçäo, e que altas pontuações na escala de busca de novidades podem se constituir em indicadores, ou fatores de risco para o abuso de inalantes


Subject(s)
Humans , Male , Female , Child , Adolescent , Hallucinogens , Hallucinogens/adverse effects
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