Does "mainstreaming" guarantee access to care for medicaid recipients with asthma?

OBJECTIVE

Recent reforms in the federal Medicaid program have attempted to integrate beneficiaries into the mainstream by providing them with managed care options. However, the effects of mainstreaming have not been systematically evaluated.

DESIGN

Cross-sectional survey.

SETTING/PARTICIPANTS

A sample of 478 adult, nonelderly asthmatics followed by a large Northern California medical group.

MEASUREMENTS AND MAIN RESULTS

We examined differences in self-reported access by insurance status. Compared to patients with other forms of insurance, patients covered by the state's Medicaid program (Medi-Cal) were more likely to report access problems for asthma-related care, including difficulties in reaching a health care provider by telephone, obtaining a clinic appointment, and obtaining asthma medication. Adjusting for relevant clinical and sociodemographic variables, Medi-Cal patients were more likely to report at least one access problem compared to non-Medi-Cal patients (adjusted odds ratio [AOR], 3.34; 95% confidence interval [CI], 1.43 to 7.80). Patients reporting at least one access problem were also more likely to have made at least one asthma-related emergency department visit within the past year (AOR, 4.84; 95% CI, 2.41 to 9.72). Reported barriers to care did not translate into reduced patient satisfaction.

CONCLUSIONS

Within this population of Medicaid patients, the provision of health insurance and care within the mainstream of an integrated health system was no guarantee of equal access as perceived by the patients themselves.

Pathogenicity determinants in the complex virus population of a Plum pox virus isolate

Several subisolates were separated from a single Plum pox virus (PPV) isolate, PPV-PS. In spite of an extremely high sequence conservation (more than 99.9% similarity), different subisolates differed largely in pathogenicity in herbaceous hosts and infectivity in woody plants. The severity of symptomatology did not seem to correlate with virus accumulation. Sequence analysis and site-directed mutagenesis demonstrated that single amino acid changes in the helper component (HC) protein caused a drastic effect on virus symptoms in herbaceous hosts and notably modified virus infectivity in peach seedlings. These results indicate that HC variation might play an important role in virulence evolution of natural plant virus infections. Moreover, the analysis of Potato virus X (PVX)-HC chimeras showed that the identified HC amino acid changes had parallel effects on the severity of symptoms caused by PPV and on HC-induced enhancement of PVX pathogenicity, indicating that HC functions in potyvirus symptomatology and in synergism with other viruses have overlapping determinants.

[Sublingual immunotherapy with cat epithelial extract. Personal experience]

Because cats are a common pet in many houses and tourist complexes in the Canary Islands, sensitization to cat epithelium is a frequent problem. A total of 19.2% of patients with intrinsic asthma are sensitized to cat epithelium. In the Canary Islands, the percentage of sensitization among patients with a household cat is 18.1%, which higher is higher than in the rest of Spain (11.9). Many patients with extrinsic asthma sensitized to house dust mites undergo conventional subcutaneous immunotherapy but evolution is unsatisfactory due to sensitization to cat epithelium (whether a cat is present or not). The aim of this study was to evaluate the clinical effectiveness of sublingual immunotherapy with extract of cat epithelium in monosensitized patients with perennial allergic rhinitis and/or bronchial asthma. Forty patients monosensitized to cat epithelium were selected. Of these, 20 were administered sublingual immunotherapy and another 20 received placebo. The following evaluation was carried out in both groups: in vivo and in vitro: symptom score, skin tests, nasal challenge with cat epithelium, specific IgE determination, specific IgG4 and eosinophilic cationic protein. After 1 year of treatment the cumulative dose was 3.6 micrograms of Fe ld I, equivalent to 10 ng/drop. Duration of treatment was 365 days. Our conclusions, based on our patients in the Canary Islands, were the following: 1. Sublingual Fel d I therapy is effective after 1 year of treatment. 2. There were no modifications in IgE, eosinophilic cationic protein or skin tests. 3. An increase in IgG4 occurred which was related to clinical improvement. 4. In general, tolerance was good, except in one patient who presented urticaria and sublingual pruritus. 5. In polysensitized patients, sublingual immunotherapy to cat epithelium is complementary to immunotherapy to dermatophagoides.

Protection of rabbits against rabbit hemorrhagic disease virus by immunization with the VP60 protein expressed in plants with a potyvirus-based vector

A new plum pox potyvirus (PPV)-based vector has been constructed for the expression of full-length individual foreign proteins. The foreign sequences are cloned between the NIb replicase and capsid protein (CP) cistrons. The heterologous protein is split from the rest of the potyviral polyprotein by cleavage at the site that originally separated the NIb and CP proteins and at an additional NIa protease recognition site engineered at its amino-terminal end. This vector (PPV-NK) has been used to clone different genes, engendering stable chimeras with practical applications. We have constructed a chimera expressing high levels of jellyfish green fluorescent protein, which can be very useful for the study of PPV molecular biology. The VP60 structural protein of rabbit hemorrhagic disease virus (RHDV) was also successfully expressed by making use of the PPV-NK vector. Inoculation of extracts from VP60-expressing plants induced a remarkable immune response against RHDV in rabbits, its natural host. Moreover, these animals were protected against a lethal challenge with RHDV.

Identification of Plum pox virus Determinants Implicated in Specific Interactions with Different Prunus spp

ABSTRACT The characterization of pathogenic properties of two infectious clones of Plum pox virus (PPV) isolates, pGPPV (D group) and pGPPVPS (M group), was investigated in their woody hosts (seedlings of Prunus spp.). The two clones differed in their ability to infect plum and peach cultivars, from no infection to local and systemic infection. The phenotype determinants were located with a set of chimeric viruses from the two clones. In plum, determinants of systemic infection were located in a genomic fragment encoding the P3 and 6K1 proteins, which might influence genome amplification or virus movement. The capacity of pGPPVPS to induce stable local and systemic infections in peach was not located accurately and might be influenced by multiple determinants carried by different regions of the genome, excluding those encoding the protein 1, the majority of helper component, nuclear inclusions a and b, and coat protein. We conclude that PPV infections of plum and peach are governed by different determinants.

Analysis of discrimination threshold on the tritan axis

Discrimination thresholds on the tritan axis were obtained for an extensive group of 66 stimuli: in some of the stimuli, S-cone trolands were held constant by keeping the product of the S-cone excitation level and the luminance unchanged, while in others only the luminance was changed to establish various S-cone troland values. These thresholds depended clearly on the S-cone value of the stimuli, while they remained almost constant against the retinal illumination. Thus, we noted that the excitation of the L - 2M channel had practically no influence over the discrimination threshold on the tritan axis, although this independence of delta S from L - 2M was not so obvious when the S value was high. With our data, we performed different fits, and found that the fit including the terms S, (L - 2M) and (L + M) adapted better to our results.

Pulsed-field gel electrophoriesis analyis of Aeromonas salmonicida ssp. salmonicida

A total of 133 strains of Aeromonas salmonicida ssp. salmonicida, isolated from a wide variety of sources, were characterized by pulsed-field gel electrophoresis patterns. Sixteen profiles were demonstrated, with one profile being predominant in samples from all the countries and species of fish. Our results suggest a clonal distribution of this subspecies, with a predominant clone being responsible for most of the outbreaks worldwide.

Stochastic independence of color-vision mechanisms confirmed by a subthreshold summation paradigm

We have used a subthreshold summation protocol to analyze spatial color-color interaction. By means of a CRT color monitor, we measured the threshold contours for a spatial frequency of 0.5 cycles/degree. Heterochromatic flicker photometry was used to obtain isoluminance. The results suggest that the blue-yellow (b-y) and red-green (r-g) contrast thresholds remained unchanged by the addition of fixed r-g and b-y subthreshold pedestals. Our subthreshold summation data then support the stochastic independence of colorvision mechanisms derived from Mullen and Sankeralli's work [Vision Res. 39, 733 (1999)] despite the differences that exist between the two experimental methods.

Construction of a stable and highly infectious intron-containing cDNA clone of plum pox potyvirus and its use to infect plants by particle bombardment

An infectious plum pox potyvirus cDNA clone was constructed placing a copy of the full-length sequence of the virus genome between an enhanced cauliflower mosaic virus 35S promoter and a nopaline synthase termination signal. Stabilization of the clone and faster growth of bacteria, in addition to higher plasmid yield, followed a modification consisting of the insertion of an intron which interrupted the viral open reading frame at the P3 region. This intron-containing clone was infectious when inoculated into plants after undergoing in vivo transcription and splicing. Particle bombardment delivery of the cDNA greatly increased the efficiency of plant infection.

Visual system's adjustments to illuminant changes: heuristic-based model revisited

This study evaluates the effect of illuminant changes along the two post-receptoral mechanisms: red-green (L - 2M) and yellow-blue (L + M - S). By means of a CRT colour monitor, Mondrian-type scenes were simulated and a series of asymmetric colour matches were made with five test illuminants. The standard objects comprising the scenes were simulations of surfaces under equal-energy illuminant and were selected according to lines of equal excitation of the red-green and the yellow-blue mechanisms. Results show that observers' matches are well predicted by assuming affine transformations between test and standard illuminant conditions. The best linear fits derived from the data corroborates the previous heuristic-based algorithms [Zaidi Q. (1998) Journal of the Optical Society of America A. 7. 1767-1776] although some discrepancies were found. Results along red-green mechanism confirm that the significant effect of the illuminant is an additive change along this axis, while data for yellow-blue mechanism suggest that illuminant induces not only multiplicative changes along this axis but additive too. In addition, we found that memory factors involved in the experiment could influence the observers' matches and would be taken into account as responsible of the differences found between the yellow-blue and the red-green systems.

Sociodemographic factors and the assignment of do-not-resuscitate orders in patients with acute myocardial infarctions

OBJECTIVES

This study examined the impact of sociodemographic and clinical factors, measured at the individual or ecological (zip code) level, on the assignment of do-not-resuscitate (DNR) orders.

DESIGN

This was a retrospective study (analysis of secondary data).

SUBJECTS

We used a probability sample of 974 patients admitted to 30 medium to large California hospitals with acute myocardial infarctions in 1990 to 1991; the sample was originally designed to validate risk adjustment with administrative data.

METHODS

Multivariate logistic regression was used to adjust DNR assignment for age, gender, race, probability of death, functional impairments, payment source, hospital teaching status, and ecological measures of educational attainment, home ownership, and income.

RESULTS

DNR assignment was inversely associated with black race and positively associated with age, probability of death, cognitive impairment, and poor nutritional status. When the probability of death was very low, DNR orders were assigned less frequently to men than to women (odds ratio [OR], 0.4; 95% confidence interval [CI], 0.2 to 0.7 at probability of death = 0.10). However, men were significantly more likely to receive a DNR order than women when the probability of death was very high (OR, 4.4; 95% CI, 1.2 to 16.3 at probability of death = 0.90).

CONCLUSIONS

Older, white, sicker, or functionally impaired patients receive DNR orders more often than younger, black, healthier, or functionally intact patients do. Adjusting for these factors, DNR assignment is associated with gender through an interaction involving the probability of death. Future studies should reexamine the impact of these factors on DNR assignment and explore the role of patient values and patient-physician communication barriers.

Preservation of 5'-end integrity of a potyvirus genomic RNA is not dependent on template specificity

Full-length in vitro transcripts of plum pox potyvirus (PPV) genomic RNA with mutations altering the number of 5'-terminal adenosine residues were able to infect Nicotiana clevelandii plants, whereas a mutant with a substitution of adenosine in position 2 by guanosine failed to infect. The genomic 5' end was template-independently repaired during in vivo RNA synthesis producing wild-type viral progeny. Putative models of replication initiation are discussed.

Frequency of germ-line BRCA1 mutations among Spanish families from a Mediterranean area

We have carried out a study of breast cancer in Spanish families in which the entire coding region of the BRCA1 gene have been analyzed. To identify BRCA1 mutations, PTT and CSGE methods were used followed by direct sequencing. We investigated 51 breast cancer women with a family history. Among these we have identified 7 frameshifts mutations (15%), 185delAG (4 times), 1623del5 and 3450del4 (2 times), and 3 missense mutations, Ser1613Gly, Met1652Ile and Ala1708Glu, which are likely polymorphisms. These findings show that BRCA1 is implicated in a fraction of Spanish familial breast cancer similar to other countries. There was association between bilateral breast cancer and BRCA1 mutations. The CSGE technique has been demonstrated to be a highly reliable method for mutation screening because of its sensitivity and high throughput.

Identification of a pathogenicity determinant of Plum pox virus in the sequence encoding the C-terminal region of protein P3+6K(1)

A full-length genomic cDNA clone of a plum pox potyvirus (PPV) isolate belonging to the M strain (PPV-PS) has been cloned downstream from a bacteriophage T7 polymerase promoter and sequenced. Transcripts from the resulting plasmid, pGPPVPS, were infectious and, in herbaceous hosts, produced symptoms that differed from those of virus progeny of pGPPV, a full-length genomic cDNA clone of the D strain PPV-R. Viable PPV-R/-PS chimeric viruses were constructed by recombination of the cDNA clones in vitro. Analysis of plants infected with the different chimeras indicated that sequences encoding the most variable regions of the potyvirus genome, the P1 and capsid protein coding sequences, were not responsible for symptom differences between the two PPV isolates in herbaceous hosts. On the contrary, complex symptomatology determinants seem to be located in the central region of the PPV genome. The results indicate that a genomic fragment that encodes 173 aa from the C-terminal part of the P3+6K(1) coding region is enough to confer, on a PPV-R background, a PS phenotype in Nicotiana clevelandii. This pathogenicity determinant also participates in symptom induction in Pisum sativum, although the region defining the PS phenotype in this host is probably restricted to 74 aa.

Assessment of CO2 arteriography in arterial occlusive disease of the lower extremities

PURPOSE

To compare the diagnostic ability and usefulness of carbon dioxide arteriography with that of angiography using iodinated contrast medium in ischemia of the lower extremities.

METHODS

Between April 1997 and February 1998 arteriography was performed systematically in 50 consecutive patients (42 men, eight women; average age, 65 years), who presented with peripheral vascular disease of the arteries of the lower extremities, with use of both CO2 and iodinated contrast medium. Untoward events that occurred during the examinations and the resulting clinical problems were recorded. Subsequently, two radiologists carried out a double-blind evaluation of the images obtained for each segment (aorta, pelvis, thighs, knees, legs, and feet) using the two different contrast agents to diagnose the arterial condition (normal, aneurysm, stenosis, and occlusion). Afterward, the two types of study performed for each patient were compared to assess the overall quality of CO2 arteriography as opposed to arteriography performed with use of iodinated contrast material.

RESULTS

Forty-eight percent of the patients reported discomfort during the CO2 examinations and 18% of the studies had to be discontinued as a result. When problems relating to poor image quality were included, only 36% of the arteriograms obtained with use of CO2 were complete. Evaluation was possible in only 25% of CO2 studies of the feet. On average, the overall quality of the arteriograms obtained with use of CO2 was insufficient for diagnosis.

CONCLUSION

In the authors' experience, CO2 arteriography cannot replace procedures performed with use of iodinated contrast medium for routine examination of ischemia of the lower limbs. In most cases, because of lower tolerance to the procedure and poorer image quality, CO2 imaging was not of sufficient quality to permit diagnosis, particularly at the infrapopliteal level.

Biotechnological aspects of plum pox virus

Plum pox potyvirus (PPV), the causal agent of a devastating disease that affects stone fruit trees, is becoming a target of intense studies intended both to fight against viral infection and to develop practical applications based on the current knowledge of potyvirus molecular biology. This review focuses on biotechnological aspects related to PPV, such as novel diagnostic techniques that facilitate detection and typing of virus isolates, strategies to implement pathogen-derived resistance through plant transformation, the potential use of genetic elements derived from the virus, and the recent development of PPV-based expression vectors.

Determination of Volatile Organic Compounds in the Atmosphere Using Two Complementary Analysis Techniques

During a preliminary field campaign of volatile organic compound (VOC) measurements carried out in an urban area, two complementary analysis techniques were applied to establish the technical and scientific bases for a strategy to monitor and control VOCs and photochemical oxidants in the Autonomous Community of the Basque Country. Integrated sampling was conducted using Tenax sorbent tubes and laboratory analysis by gas chromatography, and grab sampling and in situ analysis also were conducted using a portable gas chromatograph. With the first technique, monocyclic aromatic hydrocarbons appeared as the compounds with the higher mean concentrations. The second technique allowed the systematic analysis of eight chlorinated and aromatic hydrocarbons. Results of comparing both techniques, as well as the additional information obtained with the second technique, are included.

RNA helicase activity of Semliki Forest virus replicase protein NSP2

Semliki Forest virus replicase protein nsP2 shares sequence homology with several putative NTPases and RNA helicases. NsP2 has RNA-dependent NTPase activity. Here we expressed polyhistidine-tagged nsP2 in Escherichia coli, purified it by metal-affinity chromatography, and used it in RNA helicase assays. RNA helicase CI of plum pox potyvirus was used as a positive control. Unwinding of alpha-32P-labelled partially double-stranded RNA required nsP2, Mg2+ and NTPs. NsP2 with a mutation, K192N, in the NTP-binding sequence GVPGSGK192SA could not unwind dsRNA and had no NTPase activity. This is the first demonstration of RNA helicase activity within the large alphavirus superfamily.

GRAB proteins, novel members of the NAC domain family, isolated by their interaction with a geminivirus protein

Geminiviruses encode a few proteins and depend on cellular factors to complete their replicative cycle. As a way to understand geminivirus-host interactions, we have searched for cellular proteins which interact with viral proteins. By using the yeast two-hybrid technology and the wheat dwarf geminivirus (WDV) RepA protein as a bait, we have isolated a family of proteins which we termed GRAB (for Geminivirus Rep A-binding). We report here the molecular characterization of two members, GRAB1 and GRAB2. We have found that the 37 C-terminal amino acids of RepA are required for interaction with GRAB proteins. This region contains residues conserved in an equivalent region of the RepA proteins encoded by other viruses of the WDV subgroup. The N-terminal domain of GRAB proteins is necessary and sufficient to interact with WDV RepA. GRAB proteins contain an unique acidic C-terminal domain while their N-terminal domain, of ca. 170 amino acids, are highly conserved in all of them. Interestingly, this conserved N-terminal domain of GRAB proteins exhibits a significant amino acid homology to the NAC domain present in proteins involved in plant development and senescence. GRAB1 and GRAB2 mRNAs are present in cultured cells and roots but are barely detectable in leaves. GRAB expression inhibits WDV DNA replication in cultured wheat cells. Our studies highlight the importance that the pathway(s) mediated by GRAB proteins, as well as by other NAC domain-containing proteins, might have on geminivirus DNA replication in connection to plant growth, development and senescence pathways.

Mitotic stability of infection-induced resistance to plum pox potyvirus associated with transgene silencing and DNA methylation

Plum pox potyvirus (PPV) infection of transgenic Nicotiana benthamiana plants that expressed the PPV NIb RNA replicase carrying a Gly to Val mutation at the GDD motif (NIbV lines) induced a phenotype of virus resistance and transgene silencing, which was not transmissible to the progeny after self-fertilization (H. S. Guo and J. A. García, Mol. Plant-Microbe Interact. 10:160-170, 1997). Here, we demonstrate that the induced resistance of NIbV plants is mitotically stable after plant propagation by grafting and by in vitro regeneration. Virus replication or residual virus RNA seem not to be required to maintain transgene silencing and virus resistance. Analysis by PCR (polymerase chain reaction) amplification after treatment with methylation-sensitive restriction nucleases indicates that DNA methylation is associated with establishment and maintenance of transgene silencing and virus resistance. Restoration of transgene activity and susceptibility to PPV in sexual progeny correlated with resetting of transgene DNA methylation. On the basis of these and other published results, we present a general model for post-transcriptional gene silencing in which RNA signals, generated either by a silenced nuclear gene or by virus replication, both activate a specific cytoplasmic RNA degradation pathway and induce changes (in particular, DNA methylation) in homologous nuclear genes that switch them from an active to a silenced status.

Localization of myosin-Ibeta near both ends of tip links in frog saccular hair cells

Current evidence suggests that the adaptation motor of mechanoelectrical transduction in vertebrate hair cells is myosin-Ibeta. Previously, confocal and electron microscopy of bullfrog saccular hair cells using an anti-myosin-Ibeta antibody labeled the tips of stereocilia. We have now done quantitative immunoelectron microscopy to test whether myosin-Ibeta is enriched at or near the side plaques of tip links, the proposed sites of adaptation, using hair bundles that were serially sectioned parallel to the macular surface. The highest particle density occurred at stereocilia bases, close to the cuticular plate. Also, stereocilia of differing lengths had approximately the same number of total particles, suggesting equal targeting of myosin-Ibeta to all stereocilia. Finally, particles tended to clump in clusters of two to five particles in the distal two-thirds of stereocilia, suggesting a tendency for self-assembly of myosin-Ibeta. As expected from fluorescence microscopy, particle density was high in the distal 1 micrometer of stereocilia. If myosin-Ibeta is the adaptation motor, a difference should exist in particle density between regions containing the side plaque and those excluding it. Averaging of particle distributions revealed two regions with approximately twice the average density: at the upper ends of tip links in a 700-nm-long region centered approximately 100 nm above the side plaque, and at the lower ends of tip links within the tip plaques. Controls demonstrated no such increase. The shortest stereocilia, which lack side plaques, showed no concentration rise on their sides. Thus, the specific localization of myosin-Ibeta at both ends of tip links supports its role as the adaptation motor.

Modifications in the distribution of met-enkephalin in the cat spinal cord after administration of clonidine. An immunocytochemical study

We have studied the modifications in the distribution of methionine-enkephalin in the cat spinal cord after intravenous or intrathecal administration of clonidine by using an immunocytochemical technique. In animals not treated with the substance, a very high density of immunoreactive fibers was found in layers I and II; a high density in the dorso-lateral funiculus and in the reticular formation; a moderate density in layers III, IV and V; and a low density in layer VI. However, after intravenous or intrathecal administration of clonidine a decrease in fibers containing met-enkephalin was observed in layers I and II (high or moderate density), the dorso-lateral funiculus, and the reticular formation (moderate or low density), and in layers IV and V (low or very low density). In all cases, the decrease in the immunoreactivity was more marked when clonidine was administered intrathecally. Our results suggest that clonidine induces the release of metenkephalin in the spinal cord. They further suggest that the opioid peptide released could be involved in the control of nociceptive transmission by inhibiting the release of neurotransmitters (e.g., substance P). In summary, our study shows that clonidine could be involved in antinociceptive mechanisms in the cat spinal cord.

Susceptibility to recombination rearrangements of a chimeric plum pox potyvirus genome after insertion of a foreign gene

Infectious RNA transcripts were generated from a chimeric cDNA clone of the plum pox potyvirus (PPV) genome containing the bacterial beta-glucuronidase (GUS) gene inserted between the sequences coding for the P1 and HC proteins. An artificial cleavage site specific for the NIa viral proteinase was engineered between the GUS and HC sequences to produce free GUS and HC proteins. The resulting virus PPVGus/ was stably maintained during the first round of infection, although plants remained symptomless and virus accumulation was delayed with respect to wild-type infection. PPVGus/ deleted variants, missing between 645 and 1779 nt, were detected in a subsequent plant passage. PPVGus/ deletions were confined inside the GUS gene, never affecting the P1 and HC coding regions, in contrast with previous reports of deletions in other potyvirus-based vector, in which deletions frequently reached the HC gene. These results suggest that the N-terminus of the PPV HC protein may be essential for virus viability. Analysis of the deletion endpoints showed short stretches of similarity in donor and acceptor RNAs, as well as oligo A tracts conserved in most junction sites, suggesting that deletions in PPVGus/ might take place by similarity-assisted recombination events.