Guanylin and uroguanylin stimulate lipolysis in human visceral adipocytes.

BACKGROUND/OBJECTIVES: Uroguanylin and guanylin are secreted by intestinal epithelial cells as prohormones postprandially and act on the hypothalamus to induce satiety. The impact of obesity and obesity-associated type 2 diabetes (T2D) on proguanylin and prouroguanylin expression/secretion as well as the potential role of guanylin and uroguanylin in the control of lipolysis in humans was evaluated. SUBJECTS/METHODS: Circulating and gastrointestinal expression of proguanylin (GUCA2A) and prouroguanylin (GUCA2B) were measured in 134 subjects. In addition, plasma proguanylin and prouroguanylin were measured before and after weight loss achieved either by Roux-en-Y gastric bypass (RYGB) (n=24) or after a conventional diet (n=15). The effect of guanylin and uroguanylin (1-100 nmol l(-1)) on lipolysis was determined in vitro in omental adipocytes. RESULTS: Circulating concentrations of prouroguanylin, but not proguanylin, were decreased in obesity in relation to adiposity. Weight loss achieved by RYGB increased plasma proguanylin and prouroguanylin. Obese T2D individuals showed higher expression of intestinal GUCA2A as well as of the receptors of the guanylin system, GUCY2C and GUCY2D, in omental adipocytes. The incubation with guanylin and uroguanylin significantly stimulated lipolysis in differentiated omental adipocytes, as evidenced by hormone-sensitive lipase phosphorylation at Ser563, an increase in fatty acids and glycerol release together with an upregulation of several lipolysis-related genes, including AQP3, AQP7, FATP1 or CD36. CONCLUSIONS: Both guanylin and uroguanylin trigger lipolysis in human visceral adipocytes. Given the lipolytic action of the guanylin system on visceral adipocytes, the herein reported decrease of circulating prouroguanylin concentrations in obese patients may have a role in excessive fat accumulation in obesity.

Lean techniques to improve the flow of critically ill patients in a health region with its epicenter in the intensive care unit of a reference hospital. / Técnicas «Lean¼ para la mejora del flujo de los pacientes críticos de una región sanitaria con epicentro en el servicio de medicina intensiva de un hospital de referencia.

OBJECTIVE: To analyze whether the application of Lean techniques to improve the flow of critically ill patients in a health region with its epicenter in the intensive care unit (ICU) of a reference hospital. DESIGN: Observational study with pre and post intervention analysis. SETTING: ICU of a reference hospital. PATIENTS: We design projects and a value stream map of flow and compared pre and post intervention. INTERVENTIONS: We recorded demographic data, patient transfers by EMS for lack of beds and delay times in the discharge from ICU to ward. Multidisciplinary meetings and perform daily visual panel, with high priority ICU discharge. We promote temporary relocation of critically ill patients in other special areas of the hospital. We performed a professional satisfaction questionnaire with pre and post implementation of process. We make a statistical analysis of pre and post-intervention comparisons. RESULTS: We planned for 2013 and progressively implemented in 2014. Analysis of patients entering the critical process flow 1) evaluate patients who must transfer for lack of beds, focusing on a diagnosis: pre 10/22 vs. 3/21 post (P=.045); 2) analysis of time delay in the discharge from the ICU to ward: 360.8±163.9minutes in the first period vs. 276.7±149.5 in the second (P=.036); and 3) personal professional satisfaction questionnaire, with 6.6±1.5 points pre vs. 7.5±1.1 in post (P=.001). Analysis of indicators such as the ICU acquired infections, length of ICU stay, the rate of re-admissions and mortality, with no significant differences between the two periods. CONCLUSIONS: The application of Lean techniques in the critically ill process had a positive impact on improving patient flow within the health region, noting a decrease of transfers outside the region due to lack of beds, reduced delayed discharge from ICU to conventional ward and increased satisfaction of ICU professionals.

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.

Body mass index classification misses subjects with increased cardiometabolic risk factors related to elevated adiposity.

CONTEXT: Body mass index (BMI) is widely used as a measure of overweight and obesity, but underestimates the prevalence of both conditions, defined as an excess of body fat. OBJECTIVE: We assessed the degree of misclassification on the diagnosis of obesity using BMI as compared with direct body fat percentage (BF%) determination and compared the cardiovascular and metabolic risk of non-obese and obese BMI-classified subjects with similar BF%. DESIGN: We performed a cross-sectional study. SUBJECTS: A total of 6123 (924 lean, 1637 overweight and 3562 obese classified according to BMI) Caucasian subjects (69% females), aged 18-80 years. METHODS: BMI, BF% determined by air displacement plethysmography and well-established blood markers of insulin sensitivity, lipid profile and cardiovascular risk were measured. RESULTS: We found that 29% of subjects classified as lean and 80% of individuals classified as overweight according to BMI had a BF% within the obesity range. Importantly, the levels of cardiometabolic risk factors, such as C-reactive protein, were higher in lean and overweight BMI-classified subjects with BF% within the obesity range (men 4.3 ± 9.2, women 4.9 ± 19.5 mg l(-1)) as well as in obese BMI-classified individuals (men 4.2 ± 5.5, women 5.1 ± 13.2 mg l(-1)) compared with lean volunteers with normal body fat amounts (men 0.9 ± 0.5, women 2.1 ± 2.6 mg l(-1); P<0.001 for both genders). CONCLUSION: Given the elevated concentrations of cardiometabolic risk factors reported herein in non-obese individuals according to BMI but obese based on body fat, the inclusion of body composition measurements together with morbidity evaluation in the routine medical practice both for the diagnosis and the decision-making for instauration of the most appropriate treatment of obesity is desirable.

First Report of Citrus viroid V in Moro Blood Sweet Orange in Iran.

Viroids are nonencapsidated, small, circular, single-stranded RNAs that replicate autonomously when inoculated in their host plants in which they may elicit diseases (sensitive hosts) or replicate as latent infections (tolerant hosts). Citrus viroid V (CVd-V) was initially identified in Spain (1) and later found to be present in the United States, Nepal, and the Sultanate of Oman (2). CVd-V is a member of the Apscaviroid genus within the Pospiviroidae family. Like other members of this genus, CVd-V has a restricted host range but it is able to infect a wide range of citrus and citrus related species (1,2). Within the framework of a comprehensive survey of the sanitary status of the citrus industry in Iran, a sample from a private orchard of symptomless Moro blood sweet orange (Citrus sinensis) trees grafted on Mexican lime (C. aurantifolia) located at Javanan in the southern inland region was found to be infected with CVd-V. Briefly, RNAs of nucleic acid preparations from bark tissues were separated by 5% polyacrylamide gel electrophoresis (PAGE), electrotransferred to positively charged nylon membranes, immobilized by UV cross-linking, and hybridized with a full length CVd-V specific digoxigenin (DIG)-labeled DNA probe (2). A positive identification of CVd-V was made in these extracts. This positive detection of CVd-V was confirmed by reverse transcription-PCR using CVd-V specific primers of opposite polarity (5'-GACGAAGGCCGGTGAGCAGTAAGCC-3') and (5'-GACGACGACAGGTGAGTACTTTC-3') corresponding to CVd-V positions 90 to 114 and 69 to 89, respectively. Analysis of the sequence of the 293-bp amplicon (Genbank Accession No. GQ466068) revealed 99% identity with the reference sequence (Genbank Accession No. NC010165) of CVd-V. The rod-like predicted minimum free energy secondary structure of this new variant has 68.3% paired nucleotides. The changes with respect to the reference CVd-V variant are: (i) a deletion (48→-U) located in a loop of the V domain; (ii) a substitution (155A→C) located in a loop of the TR domain of the viroid secondary structure; and (iii) two compensatory substitutions located in the upper (46A→G) and lower (244U→C) strands of the viroid secondary structure. As shown earlier, the genome of CVd-V allows little variation with a large loop located in the segment I of the secondary structure (2) being the most amenable for mutations/changes. Among the viroids that have been found naturally infecting citrus, the members of the genus Apscaviroid are not associated with specific diseases but they cause a reduction of tree size and fruit harvest (3), an effect that is enhanced when several viroids coinfect the same plant (4). Therefore, the presence of CVd-V should be considered in further indexing tests aimed at the production and distribution of pathogen-free plants in Iran. References: (1) P. Serra et al. Virology 370:102, 2008. (2) P. Serra et al. Phytopathology 98:1199, 2008. (3) C. Vernière et al. Plant Dis. 88:1189, 2004. (4) C. Vernière et al. Phytopathology 96:356, 2006.

[Nanotechnology applied to the transport of antibiotics in orthopedics and traumatology]. / Nanotecnología aplicada a la transportación de antibióticos en ortopedia y traumatología.

Bone infection and implants are a real problem in orthopedics. The formation of biofilm as well as multi-existing pathogens to antibiotics, make fighting them a difficult challenge with the tools we have today. With the aim of knowing the current state of nanotechnology applied to the transport of antibiotics in traumatology and orthopedics, and their projection in the future. We conducted a bibliographic review in June 2019. While much development of the topic and work on humans is lacking, experimental studies show that nanotechnology applied to antibiotic transport promises to be an important weapon in the treatment of bone infections in the future.

La infección ósea y de los implantes son un verdadero problema en traumatología y ortopedia. La formación de biofilm, así como patógenos multirresistentes a antibióticos hacen que combatirlas sea un difícil reto con las herramientas que hoy tenemos. Con el objetivo de conocer el estado actual de la nanotecnología, aplicada a la transportación de antibióticos en traumatología y ortopedia y su proyección a futuro, realizamos una revisión bibliográfica en Junio de 2019. Si bien falta mucho desarrollo del tema y trabajos sobre humanos, los estudios experimentales muestran que la nanotecnología aplicada a la transportación de antibióticos promete ser un arma importante en el tratamiento de las infecciones óseas a futuro.

A novel hybridization approach for detection of citrus viroids.

Citrus plants are natural hosts of several viroid species all belonging to the family Pospiviroidae. Previous attempts to detect viroids from field-grown species and cultivars yielded erratic results unless analyses were performed using Etrog citron a secondary bio-amplification host. To overcome the use of Etrog citron a number of RT-PCR approaches have been proposed with different degrees of success. Here we report the suitability of an easy to handle northern hybridization protocol for viroid detection of samples collected from field-grown citrus species and cultivars. The protocol involves: (i) Nucleic acid preparations from bark tissue samples collected from field-grown trees regardless of the growing season and storage conditions; (ii) Separation in 5% PAGE or 1% agarose, blotting to membrane and fixing; (iii) Hybridization with viroid-specific DIG-labelled probes and detection with anti-DIG-alkaline phosphatase conjugate and autoradiography with the CSPD substrate. The method has been tested with viroid-infected trees of sweet orange, lemon, mandarin, grapefruit, sour orange, Swingle citrumello, Tahiti lime and Mexican lime. This novel hybridization approach is extremely sensitive, easy to handle and shortens the time needed for reliable viroid indexing tests. The suitability of PCR generated DIG-labelled probes and the sensitivity achieved when the samples are separated and blotted from non-denaturing gels are discussed.

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.

[Therapeutic use and profile of toxicity of the FOLFOX4 regimen]. / Uso terapéutico y perfil de toxicidad del esquema FOLFOX4.

INTRODUCTION: Since the publication of the MOSAIC test results in 2004, the FOLFOX4 regimen has been established as an adjuvant treatment which is recommended in stage III colorectal cancer. The aim of this study is to assess the use of this regimen in our field and to describe its toxicity. METHODS: Descriptive study of treatments with FOLFOX4 prescribed between April 2005 and March 2007. The data was obtained from the Farhos Oncología programme and clinical records. The following data was collected: age, gender, diagnosis, stage of the illness (TNM classification) and adverse reactions, expressing severity according to Common Toxicity Criteria 2.0. RESULTS: The FOLFOX4 regimen was prescribed for 39 patients (24 men and 15 women) with an average age of 59. The diagnoses were: 28 colon cancer (4 stage II, 17 stage III, and 7 stage IV), 10 rectal cancer (1 stage II, 4 stage III, and 5 stage IV) and 1 stage IV gastric cancer. The most frequent adverse reactions were peripheral neuropathy (82 %), neutropenia (56.4 %) and diarrhoea (53.9 %.) When the study was completed, 9 patients continued active treatment with the regimen (average 6.8 cycles.) Of the 30 remaining patients only 16 people completed the 12 planned cycles. 14 patients stopped their treatment (an average of 8.1 cycles) due to toxicity in 10 cases, clinical progression in 3 cases and one patient died. Of the total 368 cycles administered, 68 suffered administration delays and 22 had the dosage reduced. CONCLUSION: The use of the FOLFOX4 regimen has been adjusted to uses with some solid scientific evidence, but its toxicity has limited its use and has made administering the planned dosage levels difficult.

A single nucleotide change in Hop stunt viroid modulates citrus cachexia symptoms.

Cachexia disease of citrus is caused by Hop stunt viroid (HSVd). In citrus, pathogenic and non-pathogenic strains differ by a "cachexia expression motif" of five to six nucleotides located in the variable domain of the proposed rod-like secondary structure. Here, site-directed mutants were generated to investigate if all these nucleotides were required for infectivity and/or symptom expression. Specifically an artificial cachexia inducing mutant M0 was generated by introducing the six nucleotides changes of the "cachexia expression motif" into a non-pathogenic sequence variant and M0 was used as a template to systematically restore some of the introduced changes. The resulting mutants in which specific changes introduced to generate M0, were restored presented a variety of responses: (i) M1, obtained by introducing two insertions forming a base-pair, was infectious but non-pathogenic; (ii) M2, obtained by introducing an insertion and restoring a substitution, presented low infectivity and the resulting progeny reverted to M0; (iii) M3, obtained by restoring a single substitution in the lower strand of the viroid secondary structure, was infectious but induced only mild cachexia symptoms; (iv) M4, obtained by restoring a single substitution in the upper strand of the viroid secondary structure, was non-infectious. These results confirm that the "cachexia expression motif" plays a major role in inciting cachexia symptoms, and that subtle changes within this motif affect symptom severity and may even suppress symptom expression.

A set of novel RNAs transcribed from the chloroplast genome accumulates in date palm leaflets affected by brittle leaf disease.

Brittle leaf disease or maladie des feuilles cassantes (MFC) is a lethal disorder of date palms that has assumed epidemic proportions in the oases of southern Tunisia. After a prolonged period during which palms are declining, the disease ends with the death of the palms. Whereas no pathogen could ever be associated with the disease, leaflets of affected palms have been previously shown to be deficient in manganese. Analysis of RNA preparations from leaflets of MFC-affected palms revealed the presence of a set of novel RNAs (MFC-RNAs) of sense and antisense polarities, which are homologous to various regions of the date palm chloroplast genome, such as the regions containing genes rrn5S-trnR(ACG) and trnM(CAU)-atpE. In the RNA preparations obtained from leaflets of affected palms, some of these RNAs are present as double-stranded species (MFC-dsRNAs), as witnessed by results from cellulose chromatography, end labeling, RNase digestion, and northern hybridization with strand specific probes. These MFC-RNAs represent a novel type of host-derived RNAs, and their presence in MFC-affected date palms is of diagnostic value.

Citrus viroid V: occurrence, host range, diagnosis, and identification of new variants.

The recently described Citrus viroid V (CVd-V) has been proposed as a new species of the genus Apscaviroid within the family Pospiviroidae. Analysis of 64 samples from different citrus-growing areas has shown that CVd-V is present in the United States, Spain, Nepal, and the Sultanate of Oman. CVd-V found in six sweet orange sources from the Sultanate of Oman was identical to the reference CVd-V variant, whereas three new variants with sequence identities of 98.6% (CVd-VCA), 97.3% (CVd-VST), and 94.9% (CVd-VNE) were identified in sources from California, Spain, and Nepal, respectively. These results suggest that this viroid has not emerged recently and that it is relatively widespread. Transmission assays to sweet orange, mandarin, and mandarin hybrids, clementine, satsuma, lemon, sour orange, Tahiti lime, Palestine sweet lime, calamondin, bergamot, and kumquat have shown that all these citrus species and citrus relatives are hosts for CVd-V. Several indexing approaches, including slot blot, northern blot hybridization, and reverse transcription-polymerase chain reaction, have been evaluated for detecting CVd-V, either using Etrog citron as an amplification host or directly from commercial species and cultivars.

Interactions between citrus viroids affect symptom expression and field performance of clementine trees grafted on trifoliate orange.

ABSTRACT Citrus exocortis viroid (CEVd), Citrus bent leaf viroid (CBLVd), a noncachexia variant of Hop stunt viroid (HSVd), Citrus viroid III (CVd-III), and Citrus viroid IV (CVd-IV) were co-inoculated as two-, three-, four-, and five-viroid mixtures to Clementine trees grafted on trifoliate orange to evaluate their effect on symptom expression, tree growth, and fruit yield. Most trees infected with CEVd-containing viroid mixtures developed exocortis scaling symptoms, as did CEVd alone, whereas most trees infected with HSVd- or CVd-IV-containing mixtures developed bark-cracking symptoms. Trees infected with mixtures containing both CEVd and CVd-IV revealed the existence of antagonism between these two viroids in terms of the expected bark-scaling and cracking symptoms. Synergistic interactions also were identified in trees infected with certain viroid combinations that, in spite of lacking CEVd, expressed exocortis-like scaling symptoms. Viroid interactions also affected the expected response of trees in terms of vegetative growth and fruit yield. Trees infected with viroid combinations containing CEVd or CVd-III were smaller and produced less fruit than trees infected with mixtures not containing these viroids. Viroid interactions on scion circumference and cumulative fruit yield, in terms of additivity of their effects, were statistically confirmed using a factorial analysis of variance model with two mean estimation approaches. In single-viroid infections, CEVd, CVd-III, and, to a lesser extent, CBLVd consistently and significantly reduced tree size and fruit yield. Conversely, HSVd and CVd-IV slightly increased fruit yield and reduced scion circumference. Rare and not consistent significant interactions were detected with the five-, four-, and three-viroid combinations. Antagonistic interactions between CEVd and CVd-III or CBLVd and CVd-III were revealed over the years with consistent significance. The antagonistic interaction between CEVd and CVd-IV was highly significant over the years when additional viroids were present; however, this antagonism appeared much later in the case of an exclusive interaction. HSVd and CVd-IV showed a consistent and significant synergistic interaction on yield only when both viroids were exclusively present. These results demonstrate antagonistic or synergistic relationships between citrus viroids depending on the viroid mixtures present in the host.

A Survey of Citrus Viroids in Campania (Southern Italy).

Within a certification program of citrus, a survey covering 14 citrus fields not previously screened were randomly selected in seven areas of the Campania Region of southern Italy to evaluate the presence and distribution of citrus viroids in the region. During the last 3 years, 112 trees were visually inspected and sampled including 14 'Navelina', 8 'Washington navel', 13 'Biondo Commune', 10 'Tarocco', 6 'Valencia late', 1 'Sanguinello', and 1 'Vanilla' sweet oranges (Citrus sinensis), four sour oranges (C. aurantium), 21 'Commune' and 7 'Monreale' clementines (C. clementina), 8 'Common' and 2 'Avana' mandarins (C. reticulata), 8 'Ovale di Sorrento' and 6 'Zagara' lemons (C. lemon), 2 Tangelos (C. reticulata × C. paradisi), and 1 grapefruit (C. paradisi). Nearly all (37 of 38) mandarin and clementine trees showed cachexia-like symptoms. Severe bark scaling that is characteristic of exocortis disease was observed on a single 'Ovale di Sorrento' lemon, the only tree incidentally found to be grafted onto the exocortis-sensitive trifoliate orange (Poncirus trifoliata) rootstock, since sour orange (C. aurantium) is the main rootstock used in Campania. Samples (104 of 112) that had been graft-inoculated into Arizona 861-S1 'Etrog citron' (C. medica L.) on rough lemon (C. jambhiri Lush.) rootstock showed typical viroid symptoms. Viroid infection was confirmed by sequential polyacrylamide gel electrophoresis analysis (2) and molecular hybridization of imprinted membranes (1). Citrus exocortis viroid (CEVd), Hop stunt viroid (HSVd), and Citrus viroid III (CVd-III) were the most frequently detected, accounting respectively, for 67.9, 86.6, and 84.8% of the infected samples. Citrus viroid IV (CVd-IV) and Citrus bent leaf viroid (CBLVd) were found in 24.1 and 13.4% of the sources. CBLVd was detected in sweet orange ('Tarocco' and 'Biondo Commune') and lemon ('Ovale di Sorrento' and 'Zagara'), while CVd-IV was detected in sweet orange ('Tarocco', 'Biondo Commune', and 'Washington navel'), lemon ('Ovale di Sorrento' and 'Zagara'), clementine ('Commune'), and sour orange. Most trees (82.1%) were infected with more than one viroid species. The most frequent viroid combinations were CEVd + HSVd + CVd-III (40.2%), HSVd + CVd-III (16.1%), and CEVd + CBLVd + HSVd + CVd-III + CVd-IV (12.5%). To our knowledge, this is the first report of CEVd, CBLVd, HSVd, CVd-III, and CVd-IV in the Campania Region and the first report of CBLVd and CVd-IV in Italy. References: (1) A. Palacio et al. Eur. J. Plant Pathol.105:897, 2000. (2) R. F. Rivera-Bustamante et al. Anal. Biochem. 156:91, 1986.

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.

Proinflammatory cytokines and early neurological worsening in ischemic stroke.

BACKGROUND AND PURPOSE: The mechanisms for clinical deterioration in patients with ischemic stroke are not completely understood. Several proinflammatory cytokines are released early after the onset of brain ischemia, but it is unknown whether inflammation predisposes to neurological deterioration. We assessed the implication of interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha in early neurological worsening in ischemic stroke. METHODS: Two hundred thirty-one patients consecutively admitted with first-ever ischemic cerebral infarction within the first 24 hours from onset were included. Neurological worsening was defined when the Canadian Stroke Scale (CSS) score fell at least 1 point during the first 48 hours after admission. IL-6 and TNF-alpha were determined in plasma and cerebrospinal fluid (CSF; n=81) obtained on admission. RESULTS: Eighty-three patients (35.9%) deteriorated within the first 48 hours. IL-6 in plasma (>21.5 pg/mL; OR 37.7, CI 11.9 to 118.8) or in CSF (>6.3 pg/mL; OR 13.1, CI 2.2 to 77.3) were independent factors for early clinical worsening, with multiple logistic regression. The association was statistically significant in all ischemic stroke subtypes as well as in subjects with cortical or subcortical infarctions. IL-6 in plasma was highly correlated with body temperature, glucose, fibrinogen, and infarct volume. CSF and plasma concentrations of TNF-alpha were also higher in patients who deteriorated, but the differences observed did not remain significant on multivariate analysis. CONCLUSIONS: In addition to participating in the acute-phase response that follows focal cerebral ischemia, IL-6 levels on admission are associated with early clinical deterioration. The association between IL-6 and early neurological worsening prevails without regard to the initial size, topography, or mechanism of the ischemic infarction.

Alpha(1)-antichymotrypsin gene polymorphism in patients with stroke.

BACKGROUND AND PURPOSE: A role for proteolytic enzymes has been suggested in the pathogenesis of stroke. In a search for new genetic factors, we investigated the gene polymorphism of the serine protease inhibitor alpha(1)-antichymotrypsin (ACT) in patients with stroke. METHODS: Two hundred twenty patients with acute ischemic stroke (n=182) and primary intracerebral hemorrhage (n=38) and 70 control subjects without clinical cerebrovascular disease were genotyped for the ACT polymorphism. RESULTS: The ACT-TT genotype was more frequent in patients with primary intracerebral hemorrhage than in patients with ischemic stroke (31.6% versus 16.4%, P:<0.05) or in control subjects (21.4%, P:=0.1). After adjusting for age, gender, and vascular risk factors, the ACT-TT genotype was associated with primary intracerebral hemorrhage, with an OR of 2.3 (95% CI 1.0 to 5. 2) compared with ischemic stroke and an OR of 1.8 (95% CI 0.85 to 9. 65) compared with controls. CONCLUSIONS: Pending confirmation in a larger study, our results suggest that the ACT-TT genotype might be a risk factor for primary cerebral hemorrhage.

alpha(1)-antichymotrypsin polymorphism: a risk factor for hemorrhagic stroke in normotensive subjects.

BACKGROUND AND PURPOSE: Although genetic factors may be important in the pathogenesis of ischemic stroke (IS), little is known on the potential role of genes in most cases of hemorrhagic stroke (HS). Preliminary data showed that the TT genotype of the alpha(1)-antichymotrypsin (ACT) gene polymorphism was associated with HS, although it remained unsettled whether prevalence of this polymorphism might differ between hypertensive and normotensive HS. METHODS: Ninety-nine patients with HS, 182 patients with IS (symptomatic control subjects), and 80 asymptomatic control subjects were genotyped for the ACT polymorphism using polymerase chain reaction amplification. Chronic hypertension was recorded in 66 patients with HS. RESULTS: The ACT-TT genotype was more prevalent in patients than in asymptomatic or symptomatic control subjects: 26%, 15%, and 16%, respectively. The ACT-TT genotype was obtained in 33% of HS who lacked arterial hypertension (P<0.05). After adjustment for age, gender, and vascular risk factors, the ACT-TT genotype remained independently associated with HS (OR 2.80, 95% CI 1.19 to 6.58, compared with asymptomatic control subjects; OR 1.79, 95% CI 0.95 to 3.40, compared with symptomatic control subjects). In analyses restricted to HS in normotensive patients, the ORs were 3.10 (95% CI 1.10 to 8.68) and 2.53 (95% CI 1.04 to 6.18), respectively. CONCLUSIONS: These findings confirm in a larger series of patients the association between the ACT-TT genotype and HS. This polymorphism is more prevalent in normotensive bleedings. Pathological studies will be required to establish whether the ACT-TT genotype facilitates proteolytic rupture of vessels that harbor amyloidotic changes or another form of nonhypertensive cerebral angiopathy.

Heparin in acute stroke with atrial fibrillation: clinical relevance of very early treatment.

BACKGROUND: The risk-benefit ratio of early vs late heparinization for acute stroke with nonvalvular atrial fibrillation remains unsettled. OBJECTIVE: To clarify the relationship between timing to heparinization and functional outcome in acute cardioembolic stroke. DESIGN: Consecutive case series. SETTING: Referral center. PATIENTS: In 231 patients with stroke and nonvalvular atrial fibrillation, intravenous or subcutaneous heparin administered with the goal of achieving an activated partial thromboplastin time (APTT) 1.5 to 2.0 times control values. Delay to the initiation of heparin therapy was less than 6 hours from the onset of symptoms in 74 patients and between 6 and 48 hours in 157 patients. Functional outcome (Rankin scale) was assessed 9 +/- 3 (mean +/- SD) days from stroke onset using multivariate analysis and including in the model treatment delay, risk factors (eg, age, hypertension, diabetes, hypercholesterolemia, previous stroke, and heart disease), initial neurological severity, and baseline computed tomographic findings (eg, early signs of infarction and white matter abnormalities). Clinical symptoms on admission (Mathew score) and baseline radiological findings were evaluated in all subjects. The bleeding rate was assessed on subsequent computed tomographic (CT) scans (obtained 7 +/- 2 days after stroke). The relationship between APTT ratios and stroke recurrence or hemorrhagic worsening was also tested. MAIN OUTCOME MEASURES: Functional outcome at hospital discharge and incidence of early recurrent strokes and bleeding complications. RESULTS: Mortality (9%), hemorrhagic worsening (3.4%), and early stroke recurrence (2.1%) occurred in the hospital. Complete recovery was associated with age younger than 70 years (odds ratio [OR], 0.21; 95% confidence interval [CI], 0.05-0.70), a baseline Mathew score higher than 74 (OR, 11.5; 95% CI, 4.95-26.70), normal baseline CT findings (OR, 8.86; CI, 3.99-19.60), and early heparinization (OR, 1.7; 95% CI, 1.10-2.50). Targeted APTT ratios were achieved at 24 hours in fewer than 50% of patients. Whereas stroke recurrence was associated with lower mean APTT ratios, higher mean APTT ratios were observed in patients with symptomatic bleeding, especially on the day of bleeding. Age, admission stroke severity, blood pressure, and baseline CT findings did not predict hemorrhagic worsening. CONCLUSIONS: Delaying anticoagulation in alert patients with stroke and nonvalvular atrial fibrillation is not endorsed by the initial severity of symptoms or the early signs of infarction on CT scan. Functional recovery is improved the sooner heparin is administered. These findings suggest that heparin also has therapeutic properties. However, close APTT monitoring is warranted to lessen the incidence of untoward complications.