The behaviour and perception of illness: modulating variables of adherence in patients with haemophilia.

BACKGROUND: The recommended treatment in patients with severe haemophilia is prophylaxis. This prevents bleedings and reduces or delays the haemophilic arthropathy. Adherence defined as the follow-up of the patient to the prescriptions of the health professional to his treatment, both pharmacological and modifications in habits or stylelifes. Adherence rates in haemophilia are better than in other chronic diseases, but there remain reasons for nonadherence. The aim was to see if disease behaviour and disease perception together with coping strategies modulate adherence to treatment. MATERIAL AND METHODS: Multicenter cross-sectional descriptive study. Patients recruited in Units of Hemophilia Hospitals and Regional Haemophilia Associations. Twenty-three patients participated The instruments used are as follows: data sheet, SF-36, A36 Hemophilia-Qol, Illness Perception Questionnaire-Revised (IPQ-R), Illness Behavior Questionnaire (IBQ) and Coping Strategies Inventory (CSI) and VERITAS-Pro. RESULTS: We found that 56% of patients with haemophilia are adherent. The most relevant clinical variables were hemarthrosis, diagnosis of arthropathy and presence of any coinfection, as well as family history, labour status and sociodemographic variables. Age was not a relevant variable in adherence. The worst adherence coincides with poorer quality of life and inadequate coping style. Nonadherent patients show greater conviction of disease, perception of cyclicity, more hypochondriacal behaviour towards the illness and perception concern about possible side effects of medication. CONCLUSION: Adherence in haemophilia requires a more experiential approach and individualized education. It is important that professionals take into account the patient's perception, behaviour and attitude towards the disease to achieve a better adaptation of their coping resources.

Effectiveness of the Medtep Hemophilia online platform for adherence to prophylactic treatment in haemophilia patients: Results from a 1-year observational study.

INTRODUCTION: Medtep Hemophilia platform is an online tool that allows patients with congenital coagulopathies to keep track of their daily condition-related events with the objective of ensuring successful adherence to therapy. AIM: To assess the effectiveness of Medtep Hemophilia in improving adherence to prophylactic treatment in haemophilia A and B patients in a 1-year prospective observational study, as well as its impact on the patient's disease status. METHODS: Patients (>13 years old) received support material to familiarize themselves with Medtep Hemophilia. Adherence to treatment, quality of life (QoL) and illness perception were assessed. Values at baseline, 1, 6 and 12 months, and changes from baseline value were analysed. The Hemophilia Joint Health Score (HJHS) test was applied at baseline and study completion. RESULTS: Forty-six patients were enrolled (43 evaluable). After 1 year, 56.4% patients showed continued use of the platform (100% compliance) whereas 25.6% were inactive. Treatment adherence increased both significantly (P < .001) and progressively during the study. Similarly, improved QoL and illness perception were observed with respect to baseline in most of the questionnaire components (P < .05 after 12 months). A patient's age had no influence on the results, whereas compliant patients (>80% of platform use) tended to score better than noncompliant. The HJHS test values remained similar during the study. CONCLUSION: The Medtep Hemophilia online platform helped the studied patients with haemophilia to improve their adherence to prophylactic treatment, while increasing their QoL and illness perception, as well as joint arthropathies stabilization.

Benefit in long-term response and mortality of treatment with intravenous immunoglobulin prior to plasmapheresis in peripheral polyneuropathies.

OBJECTIVES: The benefits of plasmapheresis (PA) for neurologic autoimmune diseases have been widely demonstrated. Little is known about the long-term neurologic prognosis and course after PA and immunosuppressive (IS) and/or intravenous immunoglobulin (IVIG) treatment. We aimed to analyse features associated with short-term response and long-term outcome and prognosis (neurologic status and mortality) of peripheral polyneuropathy (PP) and central nervous system acute inflammatory disease (CNSAID) treated with PA. PATIENTS AND METHODS: A descriptive, retrospective single-centre study from January 2005 to December 2012. RESULTS: There were 26 episodes, which included 16 CNSAID and 10 PP cases. First line therapy included PA (n=4), IS drugs (n=15), and IVIG (n=7). Responses were achieved in 80% and 50% of PP and CNSAID cases, respectively. For PP, first line treatment with IVIG and no IS treatment prior to or during PA were variables associated with short-term response (P=0.067), good or stable neurologic status at the end of follow-up (P=0.008), and lower mortality rate (P=0.008). For CNSAID, initial EDSS score≥7 (P=0.019) was related to long-term good or stable neurologic status. During the study period, 177 sessions were conducted; 3.4% had technical complications and 8.5% clinical complications. However, these incidents were all minor and no PA session had to be discontinued. CONCLUSION: The response rates achieved in our patients were similar to those of other research. PA has a safe profile but double-blind, controlled studies are needed to evaluate the synergy of sequential treatment with IGIV followed by PA and the possible benefit for long-term outcome.

Citrus Viroids: Symptom Expression and Performance of Washington Navel Sweet Orange Trees Grafted on Carrizo Citrange.

Citrus are natural hosts of several viroid species. Citrus exocortis viroid (CEVd) and Hop stunt viroid (HSVd) are the causal agents of two well-known diseases of citrus, exocortis and cachexia. Other viroids have been found to induce specific symptoms and different degrees of stunting in trees grafted on trifoliate orange and trifoliate orange hybrids. A field assay was initiated in 1989 to establish the effect of CEVd, HSVd, Citrus bent leaf viroid (CBLVd), Citrus dwarfing viroid (CDVd), and Citrus bark cracking viroid (CBCVd) on Washington navel sweet orange trees grafted on Carrizo citrange rootstock. Here we report the effect of viroid infection on symptom expression, tree size, fruit production and quality evaluated from 2004 to 2007. Vegetative growth was affected by viroid infection with height and canopy volume being reduced. No bark scaling symptoms were observed in CEVd-infected trees albeit they presented lesions and blisters in the roots. Bark cracking symptoms were consistently observed in CBCVd-infected trees that were smaller with enhanced productivity and fruit size. No major effects were found as a result of infection with CBLVd, HSVd, or CDVd. The quality of the fruits was not affected by viroid infection, except for the low diameter of the fruits harvested from HSVd-infected trees. An interesting effect was identified in terms of tree productivity increase (yield/canopy volume) as a result of infection with CEVd, CDVd, and especially CBCVd.

Psychometric properties of a new short version of the State-Trait Anxiety Inventory (STAI) for the assessment of anxiety in the elderly.

INTRODUCTION: Anxiety has negative effects on the cognitive performance and psychosocial adjustment of elderly people. Given the high prevalence of anxiety symptoms in patients suffering from cognitive impairment, it has been suggested that these symptoms may be an early marker of dementia. The State-Trait Anxiety Inventory (STAI) is one of the most widely-used scales for evaluating anxiety in elderly people. However, inasmuch as the STAI may be difficult to apply to older people, having a short form of it would be desirable. METHODS: The participants comprised 489 community-dwelling individuals aged 68 years and over. All of them were volunteers in a longitudinal study for early detection of Alzheimer' Disease (Proyecto Vallecas). The full sample was divided in two homogeneous subgroups: Group A, used to reduce the number of items and response options, and Group B, the group used to determine the psychometric properties of the new short form (STAIr). RESULTS: A dichotomous Rasch model was used to obtain the STAIr. No statistically significant differences for STAIr scores were found with respect to sociodemographic variables. Psychometric properties and normative data were obtained for the new short version. CONCLUSIONS: The STAIr is composed of 13 items and data fits the model well. Since it is short and easy to apply to elderly people, STAIr will be very useful in clinical and research settings.

Nonergodic subdiffusion from Brownian motion in an inhomogeneous medium.

Nonergodicity observed in single-particle tracking experiments is usually modeled by transient trapping rather than spatial disorder. We introduce models of a particle diffusing in a medium consisting of regions with random sizes and random diffusivities. The particle is never trapped but rather performs continuous Brownian motion with the local diffusion constant. Under simple assumptions on the distribution of the sizes and diffusivities, we find that the mean squared displacement displays subdiffusion due to nonergodicity for both annealed and quenched disorder. The model is formulated as a walk continuous in both time and space, similar to the Lévy walk.

Effectiveness of two modalities of physiotherapy in the treatment of haemophilic arthropathy of the ankle: a randomized pilot study.

Although different techniques of physiotherapy have been described for the treatment of haemophilic arthropathy (HA) of ankle, hardly any studies have been applied manual therapy or educational physiotherapy and home exercises. The aim of this study was to assess the effectiveness of manual therapy and educational physiotherapy in the treatment of HA of the ankle. Thirty-one patients with HA of the ankle with a mean age of 35.29 (SD: 12.877) years randomized to manual therapy group (n = 11), educational group (n = 10) and a control group (n = 10). The two physiotherapy programmes were one with manual therapy articular traction, passive stretching of the gastrocnemius muscles, and exercises for muscle strength and proprioception (MT group) and the other with educational sessions and home exercises (E group). The study lasted for 12 weeks. The treatment with manual therapy improved the gastrocnemius muscle circumference, and the pain of ankle (P < 0.05). Six months later, MT group still enjoyed improvement. In the educational group there were improvements, but not significant, in the measured variables. No patient had ankle haemarthrosis during the study. The treatment with manual therapy improved the circumference of gastrocnemius and lessened pain in the patients with haemophilic arthropathy of the ankle.

Generalización de la fiabilidad: un enfoque metaanalítico aplicado a la fiabilidad / Reliability generalization: A meta-analytic approach to reliability coefficients

La fiabilidad no es una propiedad inherente al test, por lo que frases del tipo “la fiabilidad del test es de 0,80” son incorrectas. Ello se debe a que la fiabilidad es una propiedad de las puntuaciones obtenidas por un test en una aplicación concreta de éste. La generalización de la fiabilidad (GF) es un nuevo tipo de metaanálisis que permite examinar empíricamente la variabilidad de las estimaciones de la fiabilidad en diferentes aplicaciones de un test. Los estudios de GF están poniendo en evidencia lo inadecuado que resulta esa práctica habitual de los investigadores de inducir la fiabilidad a partir de estimaciones previas de ésta. En este artículo se presenta una panorámica del enfoque de GF, describiendo cuáles son sus fases de realización. Además, se discuten algunos de los problemas estadísticos más importantes de los estudios GF, tales como: a) procedimientos de transformación de los coeficientes de fiabilidad; b) métodos de ponderación de los coeficientes, y c) modelos estadísticos asumibles (AU)

Reliability is not a property inherent to the test, so that sentences such as “the test reliability is 0.80” are wrong. That is because reliability is a property of scores obtained in a given application o a test. Reliability generalization (RG) is a new kind of meta-analysis which enables to empirically examine the variability of the reliability estimates across different applications of a test. The RG studies are evidencing how unadvisable is the usual practice of researchers of inducing reliability from previous estimates. In this article an overview of the RG approach is presented, describing the required steps. Moreover, some of the most important statistical issues concerning RG studies are discussed, such as: (a) transforming procedures of the reliability coefficients, (b) weighting methods of the coefficients, and (c) statistical models that can be assumed (AU)

Análisis psicométrico de la escala de marcha y equilibrio de Tinetti con el modelo de Rasch / Psychometric analysis of the Performance Oriented Mobility Scale of Tinetti with the Rasch model

ObjetivoEn este estudio se presenta una aplicación del modelo de crédito parcial de la familia de modelos de Rasch a la escala de movilidad geriátrica PMOS (Tinetti, 1986, 1988) con vistas a determinar si ofrece una estructura unidimensional que permite obtener estimaciones de parámetros de habilidad y dificultad invariantes.MaterialSe empleó una versión traducida al castellano de la escala PMOS, que se administró individualmente a los pacientes que colaboraron en el estudio.MétodoDoscientos pacientes fueron evaluados con la escala PMOS. Las valoraciones de los 17 ítems fueron sometidas a un análisis psicométrico con el modelo de crédito parcial utilizando el programa ConQuest.ResultadosDoce ítems de la PMOS se ajustaron al modelo unidimensional de Rasch, evidenciando que la habilidad de las personas se puede explicar en función de un solo atributo. El resto de ítems (1, 7, 13, 15 y 17) no obtuvieron estadísticos de ajuste que permitiera asegurar que su patrón de respuestas podría explicarse a través del modelo de Rasch.ConclusionesLa metodología basada en el estudio del ajuste de los ítems a la familia de modelos de Rasch permite obtener estimaciones invariantes de los párametros de dificultad de los ítems y de habilidad de las personas. Además, el modelo de crédito parcial permite obtener estimaciones de los umbrales de las categorías con vistas a probar si los procesos discriminales de las personas son iguales para todos los ítems o varían de ítem a ítem(AU)

ObjectivesIn this study, we present an application of the partial credit model of the Rasch family of models to the PMOS scale of geriatric mobility (Tinetti, 1986, 1988) with the aim of determining whether it offers a unidimensional structure that enables us to obtain estimates of invariant parameters of ability and difficulty.MaterialA Spanish translation of the PMOS scale was used. It was administered individually to the patients who took part in this study.MethodTwo hundred patients were assessed using the PMOS scale. The evaluations of the 17 items were analyzed psychometrically with the partial credit model using the ConQuest program.ResultsTwelve items of the PMOS fitted the unidimensional Rasch model, proving that the subjects’ ability can be explained using one single attribute. The other items (1, 7, 13, 15 and 17) did not obtain goodness-of-fit statistics that would guarantee that their response pattern could be explained using the Rasch model.ConclusionsThe methodology based on the study of the fit of the items to the Rasch family of models enables us to obtain estimates of the invariant difficulty and ability parameters. Furthermore, the partial credit model enables us to obtain estimates of the thresholds of the categories with a view to testing whether the subjects’ discriminatory processes are the same for all the items or whether they vary from item to item(AU)

Effect of a Field-Source Mixture of Citrus Viroids on the Performance of 'Nules' Clementine and 'Navelina' Sweet Orange Trees Grafted on Carrizo Citrange.

A field-source mixture of citrus viroids was characterized and shown to contain Citrus exocortis viroid (CEVd), Hop stunt viroid (HSVd), Citrus bent leaf viroid (CBLVd), and Citrus dwarfing viroid (CDVd). Sequencing results showed that: (i) CEVd contained the PL and PR characteristic of class A variants; (ii) HSVd was a noncachexia variant; (iii) CBLVd was related to CVd-Ia variants; (iv) CDVd was a mixture of two types (CVd-IIIa and CVd-IIIb) of variants. The presence of the same type of variants in inoculated clementine (Citrus clementina 'Nules') and sweet orange (C. sinensis 'Navelina') trees on Carrizo citrange (Poncirus trifoliata × C. sinensis) rootstocks was confirmed. The effect of infection was determined by assessing the performance of infected and noninfected trees growing in the field. Infection resulted in small trees with reduced canopy, yielding a reduced crop. Fruit characteristics were also affected: (i) clementine and sweet orange fruits from infected trees were larger than those from noninfected trees; (ii) clementine fruits from infected trees differed in shape from those of noninfected trees; (iii) sweet orange fruits from infected trees had maturity indexes and juice contents higher than those from noninfected trees; (iv) in both species, the density of the juice, the amount of soluble solids, and the acidity of the fruits from infected trees were lower than those of fruits from noninfected trees. Infected trees had a poorly developed root system with fibrous roots containing fewer amyloplasts than noninfected trees. The results of an in vitro assay on the induction and development of roots in cultured explants are discussed.

Immunophenotyping of lymphocyte subsets in the third eyelid tissue in dogs (Canis familiaris): morphological, microvascular, and secretory aspects of this ocular adnexa.

The third eyelid is an important adnexa of the eye. The objective of this study was to evaluate (i) morphological aspects (ii) vascularization, and (iii) the immunophenotype of lymphocyte subsets in the third eyelid of dogs. Flow cytometric analysis revealed the presence of three patterns concerning the immunophenotype of the third eyelid tissue. Dogs without ocular insult or deficient tear production might belong to one of the following immunophenotype patterns: I--the number of T-cells that expressed CD3(+) CD8(+) was higher than the number of cells that expressed CD3(+)CD4(+). II--the number of cells CD3(+)C4(+) was higher than the number of cells CD3(+)CD8(+) and in this case a higher number of cells that expressed CD19 were identified. III--Proximity of values of the cells that expressed CD3(+)CD4(+) and CD3(+)CD8(+). These data might suggest that the number of lymphocyte T cells alone should not be considered a direct indicator of the presence of an immune-based inflammation. Besides, a particular population of T-cells does not indicate a particular inflammatory state. The morphological study of the third eyelid revealed a rather uncommon angioarchitecture. The artery that irrigates the eyelid crosses almost the entire length of this structure to achieve its free border, and only then, ramificates deeply towards an inner segmental level. This spatial microvascular arrangement probably results from an adaptation to the fact that the third eyelid, in the medial cantus of the eye, is inwardly compressed into a tiny space. Efficient vascularization is achieved by allowing the first ramifications of the third eyelid artery to run straight to the top. Accini secretor cells of the third eyelid show a mucin content while tubuloacinar cells are mainly serous.

Leishmaniosis--a report about the microvascular and cellular architecture of the infected spleen in Canis familiaris.

Leishmaniosis is an anthropozoonosis caused by an intracellular protozoan parasite that causes a wide spectrum of diseases in humans and dogs worldwide. In the Mediterranean basin, Portugal, Central and South America, and in the Middle East, visceral leishmaniosis is caused by Leishmania infantum. In these areas, dogs are believed to be the natural reservoirs of this parasite. In the case of visceral leishmaniosis, the spleen is one of the several hematopoietic and immunocompetent organs involved. Since this viscera is a blood filter, the authors investigated the expression of the morphological and microvascular environment and modifications of the spleen cell population related to immunological responses to this parasitic condition. The tools used to perform this study were scanning electronic microscopy of intact tissue and corrosion casts, transmission electronic microscopy, histology and immunohistochemistry. The results reveal three important modifications concerning the spleen's microvascular architecture when compared with its normal pattern, independently of the serological titer obtained with indirect immunofluorescence. (1) A marked scarcity of the sinusoidal system sheet that surrounds the central artery/arteriole of the white pulp; (2) A huge development of pulp venules and veins; (3) The presence of a surprising development of reticular fibers. The authors postulate that independent of the virulence of the parasite involved and the type of immunity prevalent in a particular host, the spleen develops blood dynamic conditions that permit reduction in the speed of blood flow so that cells involved in immunological processes can proliferate and differentiate, and also contributes to trapping lymphocytes within the area through the differentiation of characteristics that resemble those of HEV endothelial cells.

[The myth of Apollo and Marsyas. Artistic representations and anatomical studies]. / A lenda de Apolo e Mársias. Representações artísticas e estudos de anatomia de superfície.

The authors analyze an interesting sculpture found in the gardens of a 17th Century palace in Lisbon, representing the myth of Apollo and Marsyas, which led them to compare the details of the sculpture of the flayed satyr with the previous anatomic studies by Leonardo da Vinci (cc.1510-1530) or Vesalius (cc.1543). The photographic material obtained from the 17th century Italian sculpture presents amazing similitude with these, earlier, 16th century anatomical studies. As a complement to this study, the authors compare the sculptures with the artistic evidences, found throughout the world, of the 17th century interest for the representation of the myth of Apollo and Marsyas, which could be considered as a meaningful artistic movement of the Renaissance and neo-classic art. Some of the artistic representations of surface anatomy depict other motives, as is the case of the self-portrait of Michelangelo, painted in the Sistine Chapel, in honour of St. Bartholomew.

Mechanical Transmission of Citrus Viroids.

Preliminary transmission assays conducted under greenhouse conditions demonstrated that Citrus exocortis viroid (CEVd), Citrus bent leaf viroid (CBLVd), Hop stunt viroid (HSVd), Citrus viroid III (CVd-III), and Citrus viroid IV (CVd-IV) can be mechanically transmitted from citron to citron (Citrus medica) by a single slash with a knife blade. The impact of mechanical transmission of viroids by pruning and harvesting operations was also demonstrated in experimental and commercial field plots. Transmission efficiency under field conditions ranged from 4% in 'Nules' clementine to 10% in 'Navelina' sweet orange and 21% in 'Verna' lemon. Transmission efficiency varied only slightly with viroid and donor hosts. The impact of viroid transmission on tree height, canopy volume, and crop harvest was minimal. When the donor host was coinfected with several viroids, the viroids were not necessarily cotransmitted. Considerations regarding viroid transmission in other climates are discussed. Measures to control viroid spread in nurseries should be mandatory in certification programs.

The transmediastinal arteries of the human testis: an anatomical study.

Although the arterial supply of the human testis via the testicular artery is a well-studied subject, the pattern of approach that this vessel takes when reaching the gland is, on the other hand, not as well described. Based on the observation of angiological preparations of 196 adult human testes, the authors describe the presence of transmediastinal testicular vessels in one fourth of the cases. These were of two varieties, as regards the testicular mediastinum: centrifugal and centripetal. The centrifugal vessels were briefly mentioned in the nineteenth century scientific literature, undescribed in twentieth century anatomical studies and only recently referred to in color Doppler ultrasonographic studies; the centripetal vessels are previously undescribed. The authors propose the terms transmediastinal centrifugal and centripetal arteries to designate them.

Seed Transmission of Citrus leaf botch virus: Implications in Quarantine and Certification Programs.

Citrus leaf blotch virus (CLBV) was purified and characterized from a Nagami kumquat (Fortunella margarita (Lour.) Swingle), showing bud union crease when propagated on Troyer citrange (Citrus sinensis (L.) Osbeck × Poncirus trifoliata (L.) Raf.) (2). The complete nucleotide sequence of its genomic RNA was determined (4), and biological and molecular diagnosis methods were developed (1,3). CLBV, detected in several citrus cultivars from Australia, the United States (Florida and California), Japan, and Spain is usually associated with bud union crease on citrange or citumelo (C. paradisi (Macfad.) × P. trifoliata). The economic importance of CLBV for the citrus industry is presently unknown since its incidence in different citrus areas has not been evaluated, and its actual involvement in causing bud union crease on trifoliate rootstocks has not yet been proved. To assess seed transmissibility of this virus, 120 to 210 seeds from CLBV-infected Troyer citrange, Nagami kumquat, or sour orange (Citrus aurantium L.) plants were grown in a greenhouse. Individual 4-month-old seedlings were analyzed for CLBV by reverse transcriptase polymerase chain reaction, and infection was confirmed by biological indexing on Dweet tangor (C. tangerina Hort. ex Tanaka × C. sinensis (L.) Osbeck) when seedlings were approximately 18 months old. Seed transmission was found in 2.50, 2.52, and 2.46% of the citrange, kumquat, and sour orange seedlings, respectively. This finding indicates that control of CLBV spread during citrus propagation will require, not only virus-free buds, but also rootstock seedlings that originate from CLBV-free seed source trees. Because CLBV is seed transmissible, regulations of citrus certification programs may need to be changed to include increased control of seed source trees. Also, international regulations for citrus seed movement likely will have to be augmented to include a phytosanitary certification indicating that seeds have been collected from CLBV-free trees. References: (1) L. Galipienso et al. Plant Pathol. 49:308, 2000. (2) L. Galipienso et al. Arch. Virol. 146:357, 2001. (3) L. Galipienso et al. Eur. J. Plant Pathol. 110:175,2004. (4) M. C. Vives et al. Virology 287:225, 2001.

Intermediary spleen microvasculature in canis familiaris- morphological evidences of a closed and open type.

Numerous studies have been made regarding circulation via the red pulp of the spleen, and intense controversy surrounds the question as to whether or not endothelial continuity exists between arterial and venous vessels. Aware of this intense controversy, and in order to perform investigation over the spleen of dogs infected with a parasitic disease (future reports shall be done), the authors studied the vascularization of the normal dog spleen in order to define its normal pattern and evaluate the eventual changes of the circulation pattern under the parasitic condition. These studies led us to report, unequivocally, using complementary vascular replective techniques, that the normal dog's intermediary circulation is morphologically closed and of the open kind also. These findings are contrary to the thesis that defends the existence of a physiologically closed and morphologically open circulation in the dog spleen. Lymphatic vessels in the spleen of the dog are also demonstrated.

Microvasculature of the corpus epididymis of canis familiaris. A scanning electron microscopic study of microvascular corrosion casts.

The microvasculature of the corpus epididymis of adult domestic dogs (Canis familiaris) was studied using the technique of scanning electron microscopy of microvascular corrosion casts. The vascularization of the dog's corpus epididymis is accomplished by small arteries that course in the upper border of the organ. From these vessels arise first order arterioles (200-101 microm) which cross the surface of the epididymis and often show some coiling. The latter vessels supply second order arterioles (100-31 microm) which vascularize segments of the epididymal duct. The coiled and tight course of this duct is responsible for its peculiar microvascular arrangement. This is characterized by a 'bicycle-wheel' pattern and it is provided with precapillary or terminal arterioles (30-11 microm) nourishing a rich periductal network, mostly formed by anastomosing capillaries (10-3 microm). The periductal capillary network drains into postcapillary (11-30 microm), second order (31-100 microm) and first order (101-200 microm) venules, which empty into small calibre veins that course in the upper border of the epididymis. Anastomoses between vessels of the same type are often found. These are arteriovenous anastomoses mainly located at the periductal network. This study demonstrates that the epididymal microvasculature can be subdivided into a distribution microvascular network (DMN), formed by first and second order arterioles and venules, which presents a behaviour independent of the epididymal duct's sinuosities and a nutrition microvascular network (NMN), formed by precapillary arterioles, capillaries and post-capillary venules, characterised by the close relationship of the vessels with the loops of the epididymal duct.

The diversification of Citrus clementina Hort. ex Tan., a vegetatively propagated crop species.

Clementines, due to their high quality, are one of the most important cultivated citrus mandarins. As in the case of sweet orange and satsuma mandarins, genetic variability within this species is minimal when analyzed by molecular markers, because the existing varieties have not been obtained through hybridization, but through the selection of spontaneous mutations affecting traits of agronomic interest. This would explain, at least in part, the greater diversity for agronomic traits when compared to the variability for molecular markers. Another possible (nonexclusive) reason is that the types of molecular marker used are not focused on the kind of molecular change mainly involved in the origination of new clementine cultivars; i.e., are all sources of variation equally involved in the diversification of these plants? To answer this question, different kinds of markers based on primers of random sequence, simple sequence repeats, and retrotransposon sequences that may reveal point mutations, and somatic recombination and transposon activity, respectively, were used to compare the level of variability among 24 clementine varieties. Their ISSR, RAPD, and AFLP analysis provided only two polymorphic bands, distinguishing just two varieties. No variability was found by SSRs, i.e., no new allele arising through somatic recombination was detected. Instead, the amplification of sequences adjacent to retrotransposons yielded a higher number of polymorphisms (14.6 vs 2.4% for the previous mentioned marker types). Two geographical distant groups, one from North Africa and the other from Spain, have evolved in agreement with polymorphisms based on IRAP markers anchored to, at least, two different Copia-like retrotransposon sequences. Therefore, this study suggests that the DNA of this type of mobile elements is evolving faster than the DNA of other markers in this clonal lineage.

Constitutive expression of Arabidopsis LEAFY or APETALA1 genes in citrus reduces their generation time.

Citrus trees have a long juvenile phase that delays their reproductive development by between 6 and 20 years, depending on the species. With the aim of accelerating their flowering time, we transformed juvenile citrus seedlings to constitutively express the Arabidopsis LEAFY (LFY) or APETALA1 (AP1) genes, which promote flower initiation in Arabidopsis. Both types of transgenic citrus produced fertile flowers and fruits as early as the first year, notably through a mechanism involving an appreciable shortening of their juvenile phase. Furthermore, expression of AP1 was as efficient as LFY in the initiation of flowers, and did not produce any severe developmental abnormality. Both types of transgenic trees flowered in consecutive years, and their flowering response was under environmental control. In addition, zygotic and nucellar derived transgenic seedlings had a very short juvenile phase and flowered in their first spring, demonstrating the stability and inheritance of this trait. These results open new possibilities for domestication, genetic improvement, and experimental research in citrus and other woody species.