RESUMEN
Gynandromorphism, the simultaneous occurrence of both male and female genotypic and morphological characteristics in a single individual of a normally sexually dimorphic species, is rare in ticks. The phenomenon is documented previously for free-living specimens representing several tick genera, particularly Amblyomma and Hyalomma, but only rarely in Ixodes. Here we describe the first two known gynandromorphs of the blacklegged tick, Ixodes scapularis Say, collected while flagging vegetation during routine tick surveillance in the Hudson Valley region of New York State. Uniquely, both specimens display some morphological features typical of nymphs, in addition to those of both males and females.
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Ixodes/anatomía & histología , Animales , Femenino , Organismos Hermafroditas , Masculino , New YorkRESUMEN
While the research base is limited, studies have consistently reported poor oral health in elite athletes since the first report from the 1968 Olympic Games. The finding is consistent both across selected samples attending dental clinics at major competitions and more representative sampling of teams and has led to calls from the International Olympic Committee for more accurate data on oral health. Poor oral health is an important issue directly as it can cause pain, negative effects on appearance and psychosocial effects on confidence and quality of life and may have long-term consequences for treatment burden. Self-reported evidence also suggests an impact on training and performance of athletes. There are many potential challenges to the oral health of athletes including nutritional, oral dehydration, exercise-induced immune suppression, lack of awareness, negative health behaviours and lack of prioritisation. However, in theory, oral diseases are preventable by simple interventions with good evidence of efficacy. The consensus statement aims to raise awareness of the issues of oral health in elite sport and recommends strategies for prevention and health promotion in addition to future research strategies.
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Rendimiento Atlético , Salud Bucal , Atletas , Conductas Relacionadas con la Salud , Promoción de la Salud , Humanos , Fenómenos Fisiológicos de la Nutrición , Salud Bucal/normas , Higiene BucalRESUMEN
REASONS FOR PERFORMING STUDY: Clinical, radiographic and scintigraphic signs associated with spondylosis of the equine thoracolumbar spine have been poorly documented. OBJECTIVES: To establish an objective radiographic and scintigraphic grading system for spondylosis lesions; to estimate the prevalence of spondylosis in a population of horses with back pain; and to compare the results of radiography and scintigraphy. METHODS: Radiographic images of the thoracolumbar spine from 670 horses with clinical signs of back pain were graded. Scintigraphic images from horses with spondylosis lesions underwent subjective and objective analysis. Sensitivity and specificity of scintigraphy for detection of spondylosis relative to radiography for identification of spondylosis were calculated, and Chi-squared analysis was performed to test for an association between location and severity of lesions. RESULTS: Twenty-three of 670 horses (3.4%) with back pain had radiographic evidence of spondylosis. Of these horses, 14 (61%) had more than one lesion and 44% (n=22) of lesions occurred between T11-T13 vertebral bodies. Only 33% (n=28) of locations with radiographic changes had increased radiopharmaceutical uptake. CONCLUSION: Spondylosis occurs at a low prevalence in horses with back pain. It may be present alone or in association with other osseous abnormalities. The clinical significance of spondylosis needs further investigation. POTENTIAL RELEVANCE: Spondylosis is uncommon but may be a contributor to back pain in the horse.
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Enfermedades de los Caballos/patología , Cintigrafía/veterinaria , Columna Vertebral/diagnóstico por imagen , Espondilosis/veterinaria , Animales , Enfermedades de los Caballos/diagnóstico por imagen , Caballos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/patología , Radiografía , Estudios Retrospectivos , Espondilosis/diagnóstico , Espondilosis/diagnóstico por imagen , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/patologíaRESUMEN
Anopheles gambiae Giles s.s. and Anopheles arabiensis Patton (Diptera: Culicidae) are major vectors of malaria in Nigeria. We used 1115 bp of the mitochondrial COI gene to assess their population genetic structures based on samples from across Nigeria (n = 199). The mtDNA neighbour-joining tree, based on F(ST) estimates, separated An. gambiae M and S forms, except that samples of An. gambiae M from Calabar clustered with all the An. gambiae S form. Anopheles arabiensis and An. gambiae could be combined into a single star-shaped, parsimonious haplotype network, and shared three haplotypes. Haplotype diversity values were high in An. arabiensis and An. gambiae S, and intermediate in An. gambiae M; all nucleotide diversities were relatively low. Taken together, patterns of haplotype diversity, the star-like genealogy of haplotypes, five of seven significant neutrality tests, and the violation of the isolation-by-distance model indicate population expansion in An. arabiensis and An. gambiae S, but the signal was weak in An. gambiae M. Selection is supported as an important factor shaping genetic structure in An. gambiae in Nigeria. There were two geographical subdivisions in An. arabiensis: one included all southern localities and all but two central localities; the other included all northern and two central localities. Re-analysing an earlier microsatellite dataset of An. arabiensis using a Bayesian method determined that there were two distinctive clusters, northern and southern, that were fairly congruent with the mtDNA subdivisions. There was a trend towards decreasing genetic diversity in An. arabiensis from the northern savannah to the southern rainforest that corroborated previous data from microsatellites and polytene chromosomes.
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Anopheles/crecimiento & desarrollo , Anopheles/genética , ADN Mitocondrial/análisis , Variación Genética , Insectos Vectores/crecimiento & desarrollo , Insectos Vectores/genética , Animales , Anopheles/parasitología , Teorema de Bayes , Análisis por Conglomerados , Demografía , Femenino , Haplotipos , Insectos Vectores/parasitología , Malaria/epidemiología , Malaria/transmisión , Masculino , Nigeria , Crecimiento DemográficoAsunto(s)
Enfermedades Cutáneas Vesiculoampollosas/diagnóstico , Corticoesteroides/uso terapéutico , Dermatosis del Pie/tratamiento farmacológico , Dermatosis de la Mano/tratamiento farmacológico , Antagonistas de los Receptores Histamínicos H1/uso terapéutico , Humanos , Lactante , Masculino , Enfermedades Cutáneas Vesiculoampollosas/tratamiento farmacológicoRESUMEN
PURPOSE: A phase II study was conducted to evaluate the safety and efficacy of tirapazamine combined with cisplatin for the treatment of patients with advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Forty-four patients with stage IIIB/IV NSCLC were treated with a combination of tirapazamine and cisplatin. Patients received tirapazamine 260 mg/m2 administered intravenously over 2 hours, followed 1 hour later by cisplatin 75 mg/m2 administered over an additional hour, repeated every 21 days. The duration of therapy was meant to be limited to four cycles for nonresponders and eight cycles for responders. RESULTS: Ten of 44 patients (23%) showed a partial response. The estimated median survival for all patients was 37 weeks. Toxicities were treatable and included grade 3 nausea or vomiting (25%), fatigue (27.3%), and muscle cramps (4.5%). No dose reductions were necessary. CONCLUSION: The results show that tirapazamine can safely be added to cisplatin. Both the median survival and response rate observed strongly suggest that tirapazamine with cisplatin is more active than cisplatin alone.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Cisplatino/administración & dosificación , Neoplasias Pulmonares/tratamiento farmacológico , Triazinas/administración & dosificación , Adulto , Anciano , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Supervivencia , Tirapazamina , Resultado del TratamientoRESUMEN
To study the mechanisms that integrate pigment and chlorophyll a/b-binding apoprotein biosynthesis during light-harvesting complex II assembly, we have examined [beta]-glucuronidase (GUS) enzyme activities, chlorophyll contents, and cell sizes in fluorescence-activated, cell-sorting-separated single cells from transgenic Arabidopsis thaliana wild-type and immutans variegation mutant plants that express an Lhcb (photosystem II chlorophyll a/b-binding polypeptide gene)/GUS promoter fusion. We found that GUS activities are positively correlated with chlorophyll content and cell size in green cells from the control and immutans plants, indicating that Lhcb gene transcription is coordinated with cell size in this species. Compared with the control plants, however, chlorophyll production is enhanced in the green cells of immutans; this may represent part of a strategy to maximize photosynthesis in the green sectors to compensate for a lack of photosynthesis in the white sectors of the mutant. Lhcb transcription is significantly higher in pure-white cells of the transgenic immutans plants than in pure-white cells from norflurazon-treated, photooxidized A. thaliana leaves. This suggests that immutans partially uncouples Lhcb transcription from its normal dependence on chlorophyll accumulation and chloroplast development. We conclude that immutans may play a role in regulating Lhcb transcription, and may be a key component in the signal transduction pathways that control chloroplast biogenesis.
RESUMEN
The toxicity and marginal effectiveness of cytotoxic chemotherapy in metastatic non-small cell lung cancer (NSCLC) necessitates the search for new agents. Preliminary data in lung cancer and other malignant and premalignant disorders have identified retinoid compounds as potentially useful antitumor agents. Twenty-eight patients with metastatic NSCLC were treated with oral all-trans retinoic acid in a phase II trial. The study population consisted of patients with excellent performance status and minimal weight loss. Toxicities were generally mild and included cutaneous effects, headache, and myalgia. A significant number of patients developed elevations of hepatic transaminases or hyperlipidemia and 3 patients had treatment-related leukocytosis. Two patients (8%) achieved a partial response, and 1 had a mixed response. The duration of remission in the 2 responders was 7 and 13 months and the median survival of all patients 7 months. Therefore, all-trans retinoic acid has minimal activity as a single agent in NSCLC but warrants further study in combination with biological agents and chemotherapy.
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Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Tretinoina/uso terapéutico , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Tretinoina/efectos adversosRESUMEN
The immutans (im) variegation mutant of Arabidopsis thaliana contains green- and white-sectored leaves due to the action of a nuclear recessive gene. The mutation is somatically unstable, and the degree of sectoring is influenced by light and temperature. Whereas the cells in the green sectors contain normal chloroplasts, the cells in the white sectors are heteroplastidic and contain non-pigmented plastids that lack organized lamellar structures, as well as small pigmented plastids and/or rare normal chloroplasts. This indicates that the plastids in im white cells are not affected equally by the nuclear mutation and that the expression of immutans is 'plastid autonomous'. In contrast to other variegation mutants with heteroplastidic cells, the defect in im is not maternally inherited. immutans thus represents a novel type of nuclear gene-induced variegation mutant. It has also been found that the white tissues of immutans accumulate phytoene, a non-colored C40 carotenoid intermediate. This suggests that immutans controls, either directly or indirectly, the activity of phytoene desaturase (PDS), the enzyme that converts phytoene to zeta-carotene in higher plants. However, im is not the structural gene for PDS. A secondary effect of carotenoid deficiency, both in immutans and in wild-type plants treated with a herbicide that blocks carotenoid synthesis, is an increase in acid ribonuclease activity in white tissue. It is concluded that the novel variegation generated by the immutans mutation should offer great insight into the complex circuitry that regulates nuclear-organelle interactions.
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Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/ultraestructura , Carotenoides/biosíntesis , Núcleo Celular/ultraestructura , Genes de Plantas , Mutación , Orgánulos/ultraestructura , Oxidorreductasas/genética , Pigmentación/genética , Plastidios/ultraestructuraRESUMEN
All-trans retinoic acid was evaluated in metastatic measurable non-small cell lung cancer. All-trans retinoic acid was given at 175 mg/m2 orally on a daily basis. Twenty-eight patients (median age 58, 16 males, 12 women) had an ECOG performance status of 0 (26 patients) and 1 (two patients). Sixteen of the 28 had no weight loss. Eleven had between 5 and 10% and only one had greater than 10% weight loss at time of entry. Toxicities included cutaneous (cheletis 25/28), fatigue (10/28), myalgias/anthralgias (9/28), and headache (17/28). Alterations in triglycerides and hepatic transaminases were noted in a majority of patients. Two partial responses occurred in patients with adenocarcinoma. Both responses were 7 months in duration. Activity of all-trans retinoic acid in metastatic non-small cell lung cancer is minimal, but due to its low toxicity profile it should be tested in setting with other agents.
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Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Tretinoina/uso terapéutico , Adenocarcinoma/tratamiento farmacológico , Adulto , Anciano , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/secundario , Esquema de Medicación , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Análisis de Supervivencia , Resultado del Tratamiento , Tretinoina/administración & dosificación , Tretinoina/efectos adversosRESUMEN
1. Information abounds on teaching clients, partners and relatives about home i.v. therapy, but there is a lack of training for community nurses in this area. 2. Training for IV therapy has been difficult to develop in community settings, but must involve managers, specialists, and practitioners. 3. Community-led IV therapy training requires resources across acute and community sectors, with skills development through contract learning and focusing skills to specific practice contexts. 4. Training and experience in managing central venous access developed by community nurses are transferable to all clients and to other colleagues.