Life underground is one of the most challenging tasks for animals. The subterranean environment is seasonally and diurnally stable and provides shelter from predators. On the other hand food is scarce, the cost of digging is very high and closed burrows create hypoxic and hypercapnic conditions. Thus the physiological and behavioral adaptations to save energy are very important for underground dwellers. Social thermoregulation is such behavioral adaptation. Additionally, it has been suggested that social animals suffer from ?isolation stress? and that they decrease their metabolic rates when other family members are present = socio-physiological effect. In this study I measured the resting metabolic rates (RMR) of social Mashona mole-rats (Fukomys darlingi) in isolated individuals, pairs and groups of three to eight individuals. Measurements were carried out at two ambient temperatures, in the thermoneutral zone (TNZ; 30°C) to test the presence of a socio-physiological effect and below their TNZ (20°C) to test the effect of social thermoregulation. A socio-physiological effect was distinctive neither in pairs nor in larger groups. At temperature below the TNZ the Mashona mole-rat saved 21% of its energetic expense in pairs due to social thermoregulation. With an increase in group size, energetic savings rose up to four animals. In larger groups, social thermoregulation did not influence the energetic expenditure, possibly because Mashona mole-rat´s families naturally contain around four to five adults.

Introdução: As fissuras orofaciais estão entre as anomalias congênitas mais comuns e compreendem uma grande variabilidade de formas clínicas, sendo as fissuras labiopalatinas as mais comuns. A incidência de patologias da orelha média é elevada em pacientes com fissuras labiopalatinas ou palatina isolada. Nestes pacientes, pode haver uma inserção anômala da musculatura do véu palatino na tuba auditiva além de alterações estruturais na cartilagem e no lúmen da tuba. A disfunção tubária persistente ocasiona pressão intratimpânica negativa a qual leva ao início de sucessivas alterações na orelha média, muitas vezes irreversível. Objetivo: Descrever as alterações otológicas de 180 pacientes com fissura labiopalatina ou palatina isolada acompanhados no Hospital de Clínicas de Porto Alegre. Métodos: Analisaram-se 180 pacientes que consultaram no Ambulatório de Otorrinolaringologia e Fissura Palatina no período de agosto de 2001 a outubro de 2002. Além de uma história detalhada, foi realizada otoscopia com descrição detalhada dos achados e otomicroscopia sempre que possível. A análise estatística foi efetivada com o teste t de Student e o Quiquadrado, e quando necessário, foi utilizado o teste exato de Fisher. Resultados: Detectou-se 130 pacientes (72,2%) sem queixas otorrinolaringológicas na primeira avaliação. Observamos que 109 pacientes (70,3%) apresentavam fenda envolvendo o lábio e o palato e 46 pacientes (29,7%) apresentavam apenas comprometimento isolado do palato. A prevalência geral de alterações à otoscopia foi de 77,5%. Efusão na orelha média esteve presente em 80 pacientes (46,2%), otite média crônica colesteatomatosa em 11 (6,4%) e não colesteatomatosa em 9 (5,2%). Retração moderada/ severa foi o principal achado em 24 pacientes (13,9%). Observou-se uma associação linear entre a faixa etária e a presença dessas patologias. À medida que aumenta a faixa etária diminui a ocorrência de efusão na orelha média e aumenta a ocorrência de patologias mais crônicas como retração moderada/ severa, otite crônica com ou sem a presença de colesteatoma. A avaliação otorrinolaringológica continuada do paciente com fenda no palato permite a intervenção sempre que necessária e a manutenção da integridade da orelha média. / Introduction: Orofacial clefts are among the most frequent congenital anomalies, and encompass a wide variety of clinical presentations, of which labiopalatine clefts are the most common. The incidence of middle ear diseases is high in patients with labiopalatine or palatine clefts. In these patients, there is an anomalous insertion of the musculature of the palatine veil in the auditory tube, and also structural abnormalities in the cartilage and lumen of the tube. Persistent tubarian dysfunction causes a negative intratimpanic pressure which in turn gives rise to a series of sequential and often irreversible abnormalities in the middle ear. Objective: To describe otologic findings in 180 patients with labiopalatine ofrpalatine clefts evaluated and followed at Hospital de Clinicas, Porto Alegre. Methods: One hundred and eighty patients followed at the Otolaryngology and Cleft Palate Clinic from August 2001 and October 2002 were studied. Patients were evaluated with a detailed history, accurate registration of the otoscopic findings and, whenever possible, with otomicroscopy. Statistical analysis was performed with Student’s t , Chi-square and Fisher’s exact tests. Results: One-hundred and thirty patients (72.2%) had no otolaryngologic complaints at the initial evaluation. We observed that 109 patients (70.3%) had both labial and palatal clefts, while 46 patients (29.7%) had isolated palatal clefts. The overall incidence of otoscopic abnormalities was 77.5%. In 80 patients (46.2%), there was middle ear effusion, in 11 (6.4%) there was chronic cholesteatomatous otitis media, and in 9 (5.2%) noncholesteatomatous otitis media. In 24 patients (13.9%), moderate to severe retraction of the timpanic membrane was the main finding. There was a linear correlation between patient age and the presence of otolaryngologic findings; middle ear effusions were less frequent with increasing age, whereas the occurrence of chronic conditions such as moderate/severe retraction and otitis media with or without cholesteatoma were more common among older patients. Continued otolaryngological evaluation of the patients with cleft palate allows for early intervention and for the preservation of the integrity of the middle ear of these patients.

Pectobactérias (Pectobacterium spp. e Dickeya spp.) são os agentes causais da canela-preta e podridão-mole, e Ralstonia solanacearum da murcha bacteriana. A principal fonte de inóculo dessas doenças é o tubérculo-semente assintomático. As importações brasileiras de tubérculo-semente podem representar um risco à cultura. Tubérculos-semente livres de patógenos é considerada a melhor estratégia para manejar essas doenças. Entrentanto, métodos sensíveis para detecção desses patógenos são necessários. Sendo assim, o principal objetivo dessa pesquisa foi desenvolver e validar um método para detecção de pectobactérias e R. solanacearum presentes em baixa densidade populacional em tubérculos de batata, através de qPCR. A qPCR foi realizada com sondas de hidrólise (sondas TaqMan® MGB) e fluoróforo intercalante de DNA fita-dupla (SYBR Green I). Esse método poderá ser utilizado como uma ferramenta em estudos epidemiológicos, programas de certificação e inspeção quarentenária. O uso de cartões FTA para a coleta e extração do DNA dos tubérculos foi testado, utilizando três métodos de transferência de amostras: pressão direta; cone triturado em PBS; e fragmentos retirados com seringa e triturados em PBS. O primeiro método foi o mais sensível, proporcionando um limite de detecção por PCR de 1x102 UFC.mL-1. Oligonucleotídeos iniciadores foram desenhados para as bactérias-alvo, exceto para R. solanacearum, na qual se usou os oligonucleotídeos iniciadores OLI1/Y2 em PCR e qPCR. Dickeya spp. (54,9%) e R. solanacearum (52,9%) apresentaram a maior incidência nas 206 amostras analisadas por qPCR, seguidas por P. brasiliensis (16,5%), P. atrosepticum (9,2%), P. carotovorum (6,3%) e P. betavasculorum (1,9%). Esta última trata-se do primeiro registro em batata no Brasil. Associações entre as espécies bacterianas nos tubérculos também foram verificadas, onde Dickeya spp. e R. solanacearum foram encontradas em associação (24,8%) nos tubérculos, mas estavam presentes isoladamente em 20,8 e 13,4%, respectivamente. Dentro desse contexto, a presença de uma população bacteriana heterogênea nos tecidos vasculares dos tubérculos foi demonstrada. / Pectobacteria (Pectobacterium spp. and Dickeya spp.) are the causal agent of blackleg and soft rot, and R. solanacearum of bacterial wilt, in potato crop. The main source of inocula is symptomless seed potato tuber. The Brazilian imports of seed potato may pose a risk to the crop. Pathogen-free seed is the best strategy to manage these diseases. Therefore high-sensitive methods for detection of these bacteria are mandatory. Thus, the main objective of this study was to develop and validate a method for detection of pectobacteria and R. solanacearum present in low population density in potato tubers, by qPCR (absolute quantification) in assay with hydrolysis probes (TaqMan® MGB probes) and double-stranded DNA binding dye (SYBR Green I). This method can be used as a tool in epidemiological studies, certification programs, and quarantine inspection. The use of FTA cards to collection, and DNA extraction was tested using three methods: direct pressure, cone crushed in PBS, and small pieces removed with syringe and crushed in PBS. The first method was the most sensitive, providing a limit of detection by PCR of 1x102 CFU.mL-1. Primers were designed for target bacterial species, except for R. solanacearum, in which was used OLI1/Y2 primers for PCR and qPCR. Dickeya spp. (54.9%) and R. solanacearum (52.9%) had the highest incidence in the 206 samples analyzed by qPCR, followed by P. brasiliensis (16.5%), P. atrosepticum (9.2%), P. carotovorum (6.3%) and P. betavasculorum (1.9%). The occurrence of P. betavasculorum in potato is the first record of potato in Brazil. Associations between bacterial species in the tubers were also found, where Dickeya spp. and R. solanacearum were found in association (24.8%) in the tubers, but were present alone in 20.8 and 13.4%, respectively. Within this context, the presence of a heterogeneous bacterial population in the vascular tissues of the tubers was demonstrated.

Sight in subterranean mammals living in a dark ecotope has generally been assumed as not needed and therefore greatly diminished in its function. Recent neuroanatomical studies demonstrate unexpected preservation of the visual system of several African mole-rats (Bathyergidae, Rodentia). Only a few behavioural studies, testing visual abilities and discussing their adaptive significance in these rodents, have been published to date. A spontaneous preference to light stimuli of two mole-rat species, the silvery mole-rat (Heliophobius argenteocinereus) and the giant mole-rat (Fukomys mechowii), was tested in this study. Assessed results showed convincingly that both species are able to perceive light. The following experiments provided the first behavioural support to the perception of short-wavelengths in this intensively studied group of subterranean rodents.

Introdução: As fissuras orofaciais estão entre as anomalias congênitas mais comuns e compreendem uma grande variabilidade de formas clínicas, sendo as fissuras labiopalatinas as mais comuns. A incidência de patologias da orelha média é elevada em pacientes com fissuras labiopalatinas ou palatina isolada. Nestes pacientes, pode haver uma inserção anômala da musculatura do véu palatino na tuba auditiva além de alterações estruturais na cartilagem e no lúmen da tuba. A disfunção tubária persistente ocasiona pressão intratimpânica negativa a qual leva ao início de sucessivas alterações na orelha média, muitas vezes irreversível. Objetivo: Descrever as alterações otológicas de 180 pacientes com fissura labiopalatina ou palatina isolada acompanhados no Hospital de Clínicas de Porto Alegre. Métodos: Analisaram-se 180 pacientes que consultaram no Ambulatório de Otorrinolaringologia e Fissura Palatina no período de agosto de 2001 a outubro de 2002. Além de uma história detalhada, foi realizada otoscopia com descrição detalhada dos achados e otomicroscopia sempre que possível. A análise estatística foi efetivada com o teste t de Student e o Quiquadrado, e quando necessário, foi utilizado o teste exato de Fisher. Resultados: Detectou-se 130 pacientes (72,2%) sem queixas otorrinolaringológicas na primeira avaliação. Observamos que 109 pacientes (70,3%) apresentavam fenda envolvendo o lábio e o palato e 46 pacientes (29,7%) apresentavam apenas comprometimento isolado do palato. A prevalência geral de alterações à otoscopia foi de 77,5%. Efusão na orelha média esteve presente em 80 pacientes (46,2%), otite média crônica colesteatomatosa em 11 (6,4%) e não colesteatomatosa em 9 (5,2%). Retração moderada/ severa foi o principal achado em 24 pacientes (13,9%). Observou-se uma associação linear entre a faixa etária e a presença dessas patologias. À medida que aumenta a faixa etária diminui a ocorrência de efusão na orelha média e aumenta a ocorrência de patologias mais crônicas como retração moderada/ severa, otite crônica com ou sem a presença de colesteatoma. A avaliação otorrinolaringológica continuada do paciente com fenda no palato permite a intervenção sempre que necessária e a manutenção da integridade da orelha média. / Introduction: Orofacial clefts are among the most frequent congenital anomalies, and encompass a wide variety of clinical presentations, of which labiopalatine clefts are the most common. The incidence of middle ear diseases is high in patients with labiopalatine or palatine clefts. In these patients, there is an anomalous insertion of the musculature of the palatine veil in the auditory tube, and also structural abnormalities in the cartilage and lumen of the tube. Persistent tubarian dysfunction causes a negative intratimpanic pressure which in turn gives rise to a series of sequential and often irreversible abnormalities in the middle ear. Objective: To describe otologic findings in 180 patients with labiopalatine ofrpalatine clefts evaluated and followed at Hospital de Clinicas, Porto Alegre. Methods: One hundred and eighty patients followed at the Otolaryngology and Cleft Palate Clinic from August 2001 and October 2002 were studied. Patients were evaluated with a detailed history, accurate registration of the otoscopic findings and, whenever possible, with otomicroscopy. Statistical analysis was performed with Student’s t , Chi-square and Fisher’s exact tests. Results: One-hundred and thirty patients (72.2%) had no otolaryngologic complaints at the initial evaluation. We observed that 109 patients (70.3%) had both labial and palatal clefts, while 46 patients (29.7%) had isolated palatal clefts. The overall incidence of otoscopic abnormalities was 77.5%. In 80 patients (46.2%), there was middle ear effusion, in 11 (6.4%) there was chronic cholesteatomatous otitis media, and in 9 (5.2%) noncholesteatomatous otitis media. In 24 patients (13.9%), moderate to severe retraction of the timpanic membrane was the main finding. There was a linear correlation between patient age and the presence of otolaryngologic findings; middle ear effusions were less frequent with increasing age, whereas the occurrence of chronic conditions such as moderate/severe retraction and otitis media with or without cholesteatoma were more common among older patients. Continued otolaryngological evaluation of the patients with cleft palate allows for early intervention and for the preservation of the integrity of the middle ear of these patients.

Entre os problemas fitossanitários da maçã (Malus spp) estão o superbrotamento e o lenho mole, doenças associadas a fitoplasma. Para o caso do lenho mole, ainda não é totalmente aceito que um fitoplasma seja o agente causal. No entanto, vários trabalhos, usando microscopia eletrônica e enxertia de tecidos, têm apontado para a natureza fitoplasmática da doença. Mais recentemente, um fitoplasma do grupo 16SrI foi detectado em plantas de maçã cultivadas no Canadá e na República Checa. No Brasil, o lenho mole ocorre em vários estados do sul do país, sendo que pesquisas conduzidas com microscopia eletrônica e testes biológicos de transmissão por enxertia também têm evidenciado um possível fitoplasma associado à doença. O objetivo do presente trabalho foi contribuir para o conhecimento da etiologia destas doenças. Para isto, três plantas de maçã com sintomas de lenho mole, cultivadas em pomar instalado na região de Vacaria/RS, foram amostradas visando a detecção de fitoplasma, bem como a sua identificação e posterior classificação. Para detecção, foi empregada a técnica de PCR duplo com os oligonucleotídeos R16mF2/mR1 e R16F2n/R2. A identificação foi através de PCR com os oligonucleotídeos R16(III) F2/R1 e da técnica de RFLP com as enzimas de restrição AluI, HhaI, KpnI, HinfI, HpaII, MseI, RsaI e Sau3AI. Os resultados mostraram a presença de fitoplasma em 29 das 54 amostras coletadas durante o ano de 2000. As amostras de ramos e raízes coletadas no período de janeiro – abril e setembro – outubro apresentaram consistentemente fitoplasma em seus tecidos. Nas amostras colhidas em junho – agosto não houve detecção do microrganismo. A identificação molecular revelou que o fitoplasma presente em plantas sintomáticas pertencia ao grupo 16SrIII, sendo os resultados de PCR confirmados pela aplicação de RFLP. As análises de RFLP permitiram também determinar que este fitoplasma é, possivelmente, um membro do sub-grupo B. A constatação de um fitoplasma de grupo 16SrIII associado ao lenho mole em plantas de maçã cultivadas no Brasil, reforça as evidências relatadas em outros trabalhos, de que um fitoplasma seja o agente causal da doença. O fato de um fitoplasma diverso do grupo 16SrI estar associado ao lenho mole no Brasil pode ser justificado pela diversidade destes molicutes, em função da região geográfica e da variedade do hospedeiro. / The proliferation and rubbery wood diseases which are associated with phytoplasma are some of the diseases that occur in apple trees (Malus spp). In the case of rubbery wood disease, phytoplasm is not totally accepted as its causal agent. However, several researches by using electron microscopy and tissue grafting, have been able to show the phytoplasma associated with that disease. Recently, a phytoplasma from group 16SrI was detected in apple plants grown in Canada and Czech Republic. In Brazil, rubbery wood occurs in several states of the south region. Results obtained through electron microscopy and transmission biological tests using grafiting have shown a possible phytoplasma associated to the disease. The purpose of the present work was to contribute for the knowledge of that disease aetiology. Thus tissue samples from three apple plants exhibiting rubbery wood symptoms, grown at an orchard installed in the region of Vacaria/RS, were obtaind for phytoplasma detection, identification and classification. Nested PCR technique with R16mF2/mR1 and R16F2n/R2 primers was emploed to detect phytoplasma. PCR with R16(III) F2/R1 primers and RFLP technique with the restriction enzymes Alu I, Hha I, Kpn I, Hinf I, Hpa II, Mse I, Rsa I and Sau 3AI were used to phytoplasma indentification. The results showed that phytoplasma occurred in 29 of the 54 samples collected in the year of 2000. Branches and root samples obtained from January to April and from September to October exhibited phytoplasma in their tissues. In tissue samples collected from June to August, the microorganism has not been detected. The molecular identification revealed that the phytoplasm from symptomatic plants belonged to the group 16SrIII and the PCR results were confirmed by RFLP technique. Based upon the RFLP analyses it can be suggested that this phyoplasma is a member of the sub-group B. The occurrence of a phytoplasm of group 16SrIII associated to rubbery wood in apple plants grown in Brazil, reinforces the evidences related in other works, that a phytoplasm is the causal agent of that disease. The fact that a phytoplasm diferent from 16SrI group is associated to rubbery wood diseases in Brazil can be justified for the diversity of these mollicutes, due to geographical area and host.

The naked mole-rat possesses several unique physiological and molecular features that underlie their remarkably and exceptional resistance to tissue hypoxia. Elevated pattern of Epo, an erythropoietin (Epo) factor; c-fos; vascular endothelial growth factor (VEGF); and hypoxia-inducible factors (HIF-1α) contribute to the adaptive strategy to cope with hypoxic stress. Moreover, the naked mole-rat has a lower metabolic rate than any other eutherian mammal of comparable size that has been studied. The ability to actively reduce metabolic rate represents a strategy widely used in the face of decreased tissue oxygen availability. Understanding the different molecular and physiological factors that induce metabolic suppression could guide the development of pharmacological agents for the clinical management of stroke patient.

No description available.

Please read the abstract in the section 00front of this document / Dissertation (MSc (Entomology))--University of Pretoria, 2005. / Zoology and Entomology / unrestricted

The seasonality of wild caught Cape mole-rats was investigated, focusing on endocrine, neuroendocrine and neuroanatomical parameters. The Cape mole-rat reproduces only during the winter rainfall period of the western Cape Province. Interestingly, the gonadal steroid hormones do not show any significant seasonal patterns in either males or females. In addition, the pituitary does not exhibit a reduced sensitivity to GnRH stimulation during the non-breeding season in either sex. Moreover, in the brain the distribution, number and size of GnRH perikarya do not differ with respect to season. Therefore, although only producing young during a specific period of the year, the Cape mole-rat does not appear to be physiologically repressed from reproducing throughout the year. The results of this study imply that the Cape mole-rat is an opportunistic breeder that is reproductively quiescent during the dry season as a consequence of ecological factors such as lack of favourable burrowing conditions and that when opportunities avail themselves following aseasonal rainfall, reproduction may occur. The seasonality and socially induced infertility of the Natal mole-rat was examined via endocrine, neuroendocrine and neuroanatomical investigations. In contrast with the phylogenetically closely related common mole-rat and highveld mole-rat, the Natal mole-rat does not appear to breed seasonally. Post-mortem examination of animals collected revealed pregnant reproductive females throughout the year. A similar scenario is reflected in gonadal steroid concentrations, with no major seasonal differences observed in either males or females. Likewise, pituitary sensitivity to GnRH does not change over season in males or females, and all neuroanatomical parameters investigated remained stable over season in both males and females. Natal mole-rats captured for this study occur in an area with a high annual rainfall, (almost double that of the common mole-rat habitat and one and a half times that of the highveld mole-rat) and the relatively higher rainfall and hence soil moisture content may provide the Natal mole-rat with increased foraging time a result of increased periods over which the soil is optimal for burrowing. Socially induced infertility in the Natal mole-rat appears to be enforced behaviourally as a result of active incest avoidance. The circulating testosterone concentrations were not significantly different in reproductive and non-reproductive males, and likewise oestrogen concentrations did not differ between reproductive and non-reproductive females. Progesterone concentrations were very low in subordinate females, but markedly higher in reproductive females. This is not surprising since the Natal mole-rat is an induced ovulator, thus coitus is required to induce the LH surge that stimulates ovulation. The sensitivity of the pituitary to a GnRH challenge did not differ between reproductive and non-reproductive animals from either sex. No neuroanatomical differences were observed between reproductive and non-reproductive animals of either sex, however, non-reproductive males and females had significantly higher amounts of GnRH in the median eminence, implying that GnRH is synthesized and transported to the median eminence but not released in the portal system to the anterior pituitary. These findings suggest that non-reproductive animals of both sexes are not sterile, but merely sexually quiescent. Copyright / Thesis (PhD)--University of Pretoria, 2008. / Zoology and Entomology / unrestricted