ABSTRACT
OBJECTIVES: To evaluate analgesia, sedation and adverse effects of two doses of subcutaneous methadone in dogs undergoing tibial plateau levelling osteotomy. MATERIALS AND METHODS: Seventeen client-owned dogs undergoing unilateral tibial plateau levelling osteotomy were randomly allocated to receive either 0.25 mg/kg methadone (eight dogs) or 0.5 mg/kg methadone (nine dogs). All dogs were premedicated with methadone and 2 to 6 mcg/kg dexmedetomidine subcutaneously. They were induced and maintained on a standard protocol. All animals received a second dose of methadone subcutaneously 4 hours after premedication and a 4.4 mg/kg dose of carprofen subcutaneously at 8 hours after premedication. During surgery, blood pressure, heart rate and temperature were assessed every 5 minutes. Postoperatively, sedation scores, temperature, heart rate and Glasgow composite modified pain score - short form were assessed for 12 hours postoperatively. RESULTS: One of 17 (5.9%) dogs had intraoperative hypotension, nine of 17 dogs had intra-operative bradyarrhythmias and 17 of 17 dogs had intra-operative hypothermia. No dogs required intra-operative rescue. Composite modified pain score - short form scores were below the threshold for intervention in 16 of 17 (94.1%) animals. Only one of 17 (5.9%) dogs required rescue analgesia. Median sedation score was 0 by the T8 time point. Adverse events were rare in both groups with only vocalisation and hypothermia reported commonly postoperatively. CLINICAL SIGNIFICANCE: Two doses of methadone at either 0.25 or 0.5 mg/kg administered via subcutaneous injections pre-operatively and 4 hours later, along with 4.4 mg/kg carprofen subcutaneously 8 hours after the first methadone dose appear to provide sufficient pain control for up to 12 hours in dogs undergoing tibial plateau levelling osteotomy.
Subject(s)
Analgesics, Opioid , Methadone , Osteotomy , Pain, Postoperative , Tibia , Animals , Dogs , Methadone/administration & dosage , Methadone/therapeutic use , Osteotomy/veterinary , Pain, Postoperative/veterinary , Pain, Postoperative/drug therapy , Analgesics, Opioid/administration & dosage , Analgesics, Opioid/therapeutic use , Male , Female , Tibia/surgery , Injections, Subcutaneous/veterinary , Dog Diseases/surgery , Dog Diseases/drug therapy , Pain Measurement/veterinaryABSTRACT
Accurate and simultaneous multiposition near-field measurements are essential to study the time-dependent local dynamics, including heat and carrier transfer. The existing passive long-wavelength infrared (LWIR) scattering-type scanning near-field optical microscopy (s-SNOM) systems with a single probe cannot perform precise near-field measurements of the heat or carrier transporting process at the nanoscale level. Therefore, in this study, we developed a passive LWIR s-SNOM system with two probes. To test the effectiveness of the proposed passive LWIR dual-probe s-SNOM system, each probe was precisely controlled using a shear-force feedback system, and the mechanical interference between the probes was used to monitor the distance between the probes. We achieved simultaneous near-field measurements at two different positions 500 nm apart using the proposed passive LWIR dual-probe s-SNOM system. The simultaneously detected near-field signals from two different points were extracted individually, making this technique an effective nanoscale analysis tool for local carrier dynamics.
ABSTRACT
Passive scattering-type scanning near-field optical microscopy (s-SNOM) has recently been developed for studying long-wavelength infrared (LWIR) waves. It detects surface-localized waves without any external illumination or heating and enables the imaging of hot-electron energy dissipation and nanoscale Joule heating. However, the lack of a wavelength selection mechanism in the passive LWIR s-SNOM makes it difficult to perform a thorough analysis of the surface-localized waves. Here, we develop a novel passive scanning near-field optical spectroscopy with a diffraction grating. The spectroscopic optics are designed to exhibit a high signal efficiency and mechanical performance at the temperature of liquid helium (4.2 K). Using the developed passive LWIR near-field spectroscopy, the spectral information of thermally excited evanescent waves can be directly obtained without any influence from the external environment factors, including environmental heat. We have detected the thermally excited evanescent waves on a SiC/Au micropatterned sample at room temperature with a spatial resolution of 200 nm and a wavelength resolution of 500 nm at several wavelengths in the range of 14-15 µm. The obtained spectra are consistent with the electromagnetic local density of states calculated based on the fluctuation-dissipation theorem. The developed passive LWIR near-field spectroscopy enables the spectral analysis of ultrasmall surface-localized waves, making it a high-performance surface analysis tool.
ABSTRACT
Virtual photons can mediate interaction between atoms, resulting in an energy shift known as a collective Lamb shift. Observing the collective Lamb shift is challenging, since it can be obscured by radiative decay and direct atom-atom interactions. Here, we place two superconducting qubits in a transmission line terminated by a mirror, which suppresses decay. We measure a collective Lamb shift reaching 0.8% of the qubit transition frequency and twice the transition linewidth. We also show that the qubits can interact via the transmission line even if one of them does not decay into it.
ABSTRACT
Thymic carcinoma is a rare but lethal mediastinal cancer. The optimal treatment for advanced thymic carcinoma is not yet established. This report is the first known of stereotactic ablative radiotherapy (sabr) with CyberKnife (Accuray, Sunnyvale, CA, U.S.A.) as definitive therapy for thymic carcinoma. The patient, a 70-year-old woman with thymic carcinoma, invasion into neighboring organs, and pleural metastases-underwent CyberKnife sabr at 40 Gy in 5 fractions for two lesions, one in the thymus and one in the right paraspinal pleura. After 61 months of observation, a partial response was observed in the irradiated fields. However, disease progression in the non-irradiated pleura was noted. The patient underwent salvage CyberKnife sabr for the four initially nonirradiated pleural lesions. Computed tomography images obtained 10 months after the salvage therapy revealed a partial response. The patient is living, with progression-free irradiated lesions and no radiation-related toxicity. CyberKnife sabr is feasible for patients who are unable to undergo either surgery or conventionally fractionated radiation therapy.
ABSTRACT
BACKGROUND: The ability of a new generation commercial, multiplex, multi-dye test from Roche, the cobas TaqScreen MPX test, version 2.0, to detect and identify occult HBV infections was evaluated using routine donor samples from Kaohsiung Blood Bank, Taiwan. STUDY DESIGN AND METHODS: A total of 5973 samples were tested by nucleic acid amplification technology (NAT); 5898 in pools of six, 66 in pools of less than six and nine samples individually. NAT-reactive samples were retested with alternative NAT tests, and follow-up samples from the donors were tested individually by NAT and for all the HBV serological markers. RESULTS: Eight NAT-only-reactive donors were identified, and follow-up samples were obtained from six of the donors. The results indicated that all eight donors had an occult HBV infection with viral loads <12 IU/ml. CONCLUSION: The cobas(®) TaqScreen MPX test, version 2.0, has an advantage over the current Roche blood screening test, the cobas TaqScreen MPX test, for screening donations in countries with a high prevalence of occult HBV infections since the uncertainty associated with identifying samples with very low viremia is removed by the ability of the test to identify the viral target in samples that are reactive with the cobas TaqScreen MPX test, version 2.0.
Subject(s)
Blood Donors , Hepatitis B virus/isolation & purification , Nucleic Acid Amplification Techniques/methods , DNA, Viral/blood , Hepatitis B virus/genetics , Humans , Mass Screening/methods , Serologic Tests , TaiwanABSTRACT
There is an urgent need to identify biomarkers for hepatocellular carcinoma due to limited treatment options and the poor prognosis of this common lethal disease. Whole-transcriptome shotgun sequencing (RNA-Seq) provides new possibilities for biomarker identification. We sequenced â¼250 million pair-end reads from a pair of adjacent normal and tumor liver samples. With the aid of bioinformatics tools, we determined the transcriptome landscape and sought novel biomarkers by further empirical validations in 55 pairs of adjacent normal and tumor liver samples with various viral statuses such as HBV(+), HCV(+) and HBV(-)HCV(-). We identified a novel gene with coding regions, termed DUNQU1, which has a tissue-specific expression pattern in tumor liver samples of HCV(+) and HBV(-)HCV(-) hepatocellular carcinomas. Overexpression of DUNQU1 in Huh7 cell lines enhances the ability to form colonies in soft agar. Also, we identified three novel differentially-expressed protein-coding genes (ALG1L, SERPINA11 and TMEM82) that lack documented expression profiles in liver cancer and showed that the level of SREPINA11 is correlated with pathology stages. Moreover, we showed that the alternative splicing event of FGFR2 is associated with virus infection, tumor size, cirrhosis and tumor recurrence. The findings indicate that these new markers of hepatocellular carcinoma may be of value in improving prognosis and could have potential as new targets for developing new treatment options.
Subject(s)
Biomarkers, Tumor/metabolism , Carcinoma, Hepatocellular/metabolism , Liver Neoplasms/metabolism , Transcriptome , Alternative Splicing , Biomarkers, Tumor/genetics , Carcinoma, Hepatocellular/genetics , Cell Line, Tumor , Female , High-Throughput Nucleotide Sequencing , Humans , Liver/metabolism , Liver Neoplasms/genetics , Male , Organ Specificity , Protein Isoforms/genetics , Protein Isoforms/metabolism , Receptor, Fibroblast Growth Factor, Type 2/genetics , Receptor, Fibroblast Growth Factor, Type 2/metabolism , Sequence Analysis, DNAABSTRACT
BACKGROUND AND OBJECTIVE: Individuals with p phenotype lack P1, P(k) and P antigens on red blood cells, presumably as a result of deficiency in the enzyme α(1,4)galactosyltransferase (A4GALT). The aim of this study was to explore the molecular background of a Taiwanese family with p phenotype. MATERIALS AND METHODS: Blood samples from two p siblings and seven family members were investigated. The coding region of the A4GALT gene was analysed by polymerase chain reaction and direct sequencing. The wild- and mutant-complementary DNAs (cDNAs) of A4GALT were cloned into an expression vector and transfected to Chinese hamster ovary (CHO) cells. P(k) expression on the transfected cells was analysed by flow cytometry and the activities of A4GALT were measured by high-performance liquid chromatography. RESULTS: The two individuals with p phenotype were homozygous for the complex mutation, which was caused by a combined deletion and insertion between nt 418 and 428. No expression of P(k) and no enzyme activity were observed in cells transfected with the mutant construct. CONCLUSION: The first case of p phenotype in Taiwan was caused by a non-functional allele resulting from a homozygous complex mutation of A4GALT gene.
Subject(s)
Galactosyltransferases/genetics , P Blood-Group System/genetics , Alleles , Animals , CHO Cells , Cricetinae , Cricetulus , DNA Mutational Analysis , DNA, Complementary/genetics , Female , Galactosyltransferases/deficiency , Humans , Male , Mutagenesis, Insertional , Pedigree , Phenotype , Sequence Deletion , Taiwan , TransfectionABSTRACT
Utilization of phenolic acids, including gallic acid, coumaric acid, caffic acid, cinnamic acid, and ferulic acid, for methanol reduction in wine was investigated. Enzyme activities of pectinesterase and pectin lyase decreased significantly when 0.1 mg/L of gallic acid, coumaric acid, caffic acid, cinnamic acid, or ferulic acid was added. However, no inhibition on polygalacturonase activity was observed when 0.5 mg/L of phenolic acid was added. Methanol content in commercial pectic enzyme (CPE) group increased from 11.53 +/- 1.34 to 56.67 +/- 3.75 ppm in the final products. Adding gallic acid or coumaric acid with CPE inhibited the increase of methanol production. In addition, when 0.2 mg/L of phenolic acid (gallic acid or coumaric acid) was added, the amount of total phenolic acid released from CPE + gallic acid or CPE + coumaric acid groups became higher than CPE group by approximately 466 and 539 mg/L, respectively. In conclusion, the values of lightness, red content, yellow content, total pigment, and total phenolic acid increased in the presence of gallic acid or coumaric acid with CPE, suggesting that adding gallic acid or coumaric acid into winemaking process is a potential method for reducing methanol content, improving wine quality, as well as increasing healthy compounds in wine production.
Subject(s)
Carboxylic Ester Hydrolases/drug effects , Hydroxybenzoates/metabolism , Methanol/metabolism , Polygalacturonase/drug effects , Polysaccharide-Lyases/drug effects , Wine/analysis , Caffeic Acids , Carboxylic Ester Hydrolases/metabolism , Cinnamates , Coumaric Acids , Gallic Acid , Hydroxybenzoates/analysis , Hydroxybenzoates/chemistry , Methanol/analysis , Methanol/chemistry , Polygalacturonase/metabolism , Polysaccharide-Lyases/metabolism , Wine/standardsABSTRACT
In 2002, the office of the U.S. surgeon general published a report detailing the discrepancies between the quality of healthcare afforded to persons with and without mental retardation. This article examines the case of a female resident of a developmental center with profound mental retardation due to Down syndrome and degenerative hip disease. Although she was in urgent need of a total hip replacement, the operation was denied or delayed by several different surgeons. Using a survey of physician attitudes, we examine several possible motivations behind the surgeons' reluctance to perform the procedure and conclude that these reasons were not appropriate in this case. Finally, we reiterate the surgeon general's call to eradicate preconceptions held in the medical community about the population of persons with mental retardation that result in similar failures to provide adequate care.
Subject(s)
Arthroplasty, Replacement, Hip , Attitude of Health Personnel , Down Syndrome/complications , Intellectual Disability/complications , Osteoarthritis, Hip/surgery , Refusal to Treat , Adult , Female , Humans , Osteoarthritis, Hip/etiologyABSTRACT
During the enlargement of an existing hospital, quantitative polymerase chain reaction (PCR) was used to monitor Aspergillus spp. populations within the construction site. The rapid availability of results meant that the construction schedule was largely uninterrupted, while assuring that the new construction was free from contamination by the targeted Aspergillus spp.
Subject(s)
Aspergillus/isolation & purification , DNA, Fungal/genetics , Environmental Monitoring/methods , Hospital Design and Construction , Polymerase Chain Reaction , Aspergillus/genetics , Construction Materials/microbiology , Equipment Contamination/prevention & control , Evaluation Studies as Topic , United StatesABSTRACT
BACKGROUND AND OBJECTIVES: In addition to the common ABO phenotypes, numerous phenotypes with a weak expression of the A or B antigens on the red blood cells have been found. This study describes the molecular genetic analysis of the Bel phenotype in Taiwanese individuals. MATERIALS AND METHODS: The exon 6-7 region of the ABO gene of an individual with the Bel phenotype was amplified by the polymerase chain reaction (PCR), cloned, and the sequences of the exons and their adjacent splice sites were analysed. A PCR-based restriction fragment length polymorphism (RFLP) analysis was designed to detect the 502C>T nucleotide change identified in the Bel allele. Six unrelated individuals with the Bel phenotype were analysed, and samples from 40 randomly selected individuals with the common B phenotype were also assessed. RESULTS: All six unrelated Taiwanese individuals with the Bel phenotype were shown to possess a B gene with the 502C>T mutation. The mutation was not detected in the general group B population. The 502C>T nucleotide change predicts an amino acid alteration of Arg168-->Trp in the encoded B transferase. CONCLUSIONS: The results suggest a new molecular basis, a 502C>T missense mutation in the B allele, for the Bel phenotype and an association of the Bel502C>T allele with the Bel phenotype in the Taiwanese population.
Subject(s)
ABO Blood-Group System/genetics , Base Sequence , DNA/genetics , Exons , Humans , Molecular Biology , Mutation, Missense , Phenotype , Polymorphism, Restriction Fragment Length , TaiwanABSTRACT
BACKGROUND: The ABO system includes many variant subgroups. Some of them are difficult to identify serologically, leading to mistyping of blood groups. For example, Bel is often typed as O blood group. STUDY DESIGN AND METHODS: DNA sequencing and a molecular approach were explored to accurately determine the genotypes of Bel subgroups. Seven Bel blood donors and 106 individuals with other blood groups were analyzed serologically and molecularly. RESULTS: The serologic results of these seven Bel blood donors showed that their RBCs do not react with anti-B or anti-A,B, and their B antigen was detected by adsorption and elution methods. Sequencing results for exons 6 and 7 of ABO genes showed a new Bel allele with a C>T substitution at nucleotide position 502 in exon 7 of the ABO gene in all seven cases but not in other blood groups. Consequently, an amplification-created restriction site protocol was designed to detect the 502C>T genotype in Bel subgroup cases. CONCLUSION: A novel 502C>T mutation was found in the Bel subgroup in Taiwan and successfully developed a rapid and accurate molecular protocol to detect this mutation. To our knowledge, the new Bel allele that was found is unique in Taiwanese residents.
Subject(s)
ABO Blood-Group System/genetics , DNA Mutational Analysis/methods , Point Mutation , Alleles , Blood Donors , Exons , Genotype , Humans , Phenotype , TaiwanABSTRACT
A venom-specific cDNA encoding for a thrombin-like enzyme designated as mucrosobin has been cloned and sequenced from the cDNA library of the venomous gland of Trimeresurus mucrosquamatus. The full-length cDNA of mucrosobin was assembled by oligonucleotide screening and 5'-rapid amplification of cDNA ends. The amino acid sequence deduced from the cDNA consists of 257 amino acid residues with a putative signal peptide of 24 residues. It is highly homologous to the other thrombin-like enzymes (batroxobin, mucofirase, and calobin), suggesting that it is a serine proteinase with a conserved catalytic triad of His(41), Asp(84) and Ser(179) in the deduced form of mucrosobin protein. Northern blot analysis revealed that the mucrosobin gene encodes an mRNA of 1.5 kb and suggested a tissue-specific expression in the venomous gland. In an effort to study the biological property of mocrosobin, we have expressed the 28-kDa protein as inclusion bodies in Escherichia coli. For analyzing enzymatic activity, the inclusion bodies were solubilized and the recombinant protein was refolded with a two-step dialysis protocol. The refolded recombinant protein exhibited a specific beta-fibrinogenolytic activity. This study offers a possibility of using genetic engineering to acquire a functional snake venom protein with therapeutic potential.
Subject(s)
Crotalid Venoms/enzymology , Fibrinolytic Agents/metabolism , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , Escherichia coli/genetics , Fibrinogen/metabolism , Fibrinolytic Agents/chemistry , Inclusion Bodies/metabolism , Molecular Sequence Data , Protein Folding , Protein Structure, Tertiary , Rabbits , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/metabolism , Sequence Analysis , Serine Endopeptidases/chemistry , Serine Endopeptidases/genetics , Serine Endopeptidases/metabolism , Solubility , Transcription, Genetic , Trimeresurus/geneticsABSTRACT
The Jak family of protein-tyrosine kinases are crucial for the signaling of a large number of different polypeptide ligands, including the interferons, many cytokines, erythropoietin, and growth factors. Through their interaction with receptors, the Jaks initiate a signaling cascade resulting in the activation of gene transcription and ultimately a cellular response to various ligands. In addition to their role in cellular signaling, alteration of Jak activity has been implicated in several disease states. In identifying Jak2-interacting proteins with the yeast two-hybrid system, we cloned the human homologue of the Drosophila melanogaster tumor suppressor gene lethal () tumorous imaginal discs, which encodes the protein Tid56. Drosophila Tid56 and its human homologue hTid-1 represent members of the DnaJ family of molecular chaperones. The TID1 gene encodes two splice variants hTid-1(S) and hTid-1(L). We confirmed the interaction between Jak2 and hTid-1(S) or hTid-1(L) by immunoprecipitation from COS-1 cells expressing these proteins. The interaction between endogenous hTid-1 and Jak2 was shown in HEp2 cells. We further showed that hTid-1 interacts with the human interferon-gamma (Hu-IFN-gamma) receptor subunit IFN-gamma R2. In addition, using a chimeric construct where the extracellular domain of IFN-gamma R2 was fused to the kinase domain of Jak2, we showed that hTid-1 binds more efficiently to the chimera with an active kinase domain than to a similar construct with an inactive kinase domain. Additionally, the data demonstrate that hTid-1 isoforms as well as Jak2 interact with Hsp70/Hsc70 in vivo, and the interaction between Hsp70/Hsc70 and hTid-1 is reduced after IFN-gamma treatment. Furthermore, both hTid-1(S) and hTid-1(L) can modulate IFN-gamma-mediated transcriptional activity.
Subject(s)
Heat-Shock Proteins/metabolism , Interferon-gamma/metabolism , Protein-Tyrosine Kinases/metabolism , Proto-Oncogene Proteins , Signal Transduction/physiology , Animals , COS Cells , Cell Fractionation , Genes, Reporter , HSP40 Heat-Shock Proteins , HSP70 Heat-Shock Proteins/metabolism , Heat-Shock Proteins/genetics , Humans , Janus Kinase 2 , Models, Biological , Molecular Sequence Data , Protein Binding , Protein Structure, Tertiary , Recombinant Fusion Proteins/metabolism , Transcription, Genetic , Tumor Cells, Cultured , Two-Hybrid System TechniquesABSTRACT
Peroxynitrite, derived from the reaction of nitric oxide (NO(.)) with superoxide (O(2)), is a potent nitrating and oxidizing agent that can induce apoptosis in a variety of different cell types. In the present study, we investigated the possible role of peroxynitrite as a mediator of colon epithelial cell death in rat colitis. Rat colon inflammation was induced by intracolonic administration of 2,4,6-trinitrobenzenesulfonic acid (TNBS) and rats were sacrificed 24 h after TNBS administration. Expression of inducible nitric-oxide synthase (iNOS) was detected by reverse transcription-polymerase chain reaction and immunohistochemistry. The enzymatic activities of Ca(2+)-independent iNOS and Ca(2+)-dependent constitutive nitric-oxide synthase were determined biochemically. Evidence of peroxynitrite-mediated cell injury was detected by immunostaining of nitrotyrosine. Apoptosis was examined by in situ terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay and DNA gel electrophoresis. To evaluate the specific contribution of peroxynitrite to the observed cell injury, a selective iNOS inhibitor, L-N(G)-[1-iminoethyl]lysine (L-NIL), was administered after TNBS induction. Morphological examination and analysis of TUNEL/cytokeratin double immunofluorescence revealed significant apoptosis in mucosal epithelial cells. Nitrotyrosine was colocalized with TUNEL, strongly demonstrating the association of peroxynitrite with the apoptotic death of colon epithelial cells. The administration of L-NIL reduced iNOS activity in 24-h lesions by 92% and also significantly attenuated both nitrotyrosine staining and apoptotic cell counts in the colon epithelium. These results strongly suggest that local elevated level of peroxynitrite produced from increased iNOS expression and activity is a major contributor to colon epithelial apoptosis during colon inflammation.
Subject(s)
Colitis/metabolism , Colon/metabolism , Epithelial Cells/metabolism , Nitrates/metabolism , Nitric Oxide Synthase/metabolism , Tyrosine/analogs & derivatives , Animals , Apoptosis , Cell Death/drug effects , Colitis/chemically induced , Colitis/pathology , Colon/pathology , Disease Models, Animal , Epithelial Cells/drug effects , Epithelial Cells/pathology , Immunohistochemistry , In Situ Nick-End Labeling , Isoenzymes/antagonists & inhibitors , Isoenzymes/metabolism , Lysine/analogs & derivatives , Lysine/pharmacology , Nitric Oxide/blood , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase Type II , Peroxidase/metabolism , Proto-Oncogene Proteins/biosynthesis , Proto-Oncogene Proteins c-bcl-2/biosynthesis , Rats , Rats, Sprague-Dawley , Superoxides/metabolism , Trinitrobenzenesulfonic Acid , Tyrosine/metabolism , bcl-2-Associated X ProteinSubject(s)
Hydroxyeicosatetraenoic Acids/immunology , Hypersensitivity, Delayed/immunology , Lipoxins , Receptors, Leukotriene B4/immunology , T-Lymphocytes/immunology , Animals , Guinea Pigs , Hydroxyeicosatetraenoic Acids/metabolism , Male , Peritoneum/cytology , Receptors, Leukotriene B4/antagonists & inhibitors , Receptors, Leukotriene B4/metabolism , T-Lymphocytes/metabolism , Tuberculin/immunologyABSTRACT
BACKGROUND: beta-Blocker therapy is believed to modulate the detrimental effect of overcompensating neurohormonal activation in chronic heart failure. However, clinical doubts remain, particularly the physiologic sympathovagal balance. METHODS: To respond to clinical concern about worsening autonomic nervous perturbation in beta-blocker therapy of advanced congestive heart failure, 15 consecutive patients were longitudinally studied to elucidate the evolution of cardiac function versus 24-hour heart rate variability (HRV) before and after 1, 3, and 6 to 9 months of atenolol-combined therapy. RESULTS: Two patients died prematurely within 1 month. All 13 surviving patients showed improvement in New York Heart Association functional class, with decrease in left ventricular end-systolic and end-diastolic dimensions and increase in fraction shortening and ejection fraction by echocardiography after at least 3 months of atenolol use. The retarded therapeutic effect was accompanied by a general rise of total, very low, low-, and high-frequency components (9.0 +/- 0.5, 8.8 +/- 0.5, 6.2 +/- 0.6, and 6.1 +/- 0.5 vs 10.9 +/- 0.3, 10.7 +/- 0.4, 8.6 +/- 0.3, and 7.8 +/- 0.3; all P <.02) of daily HRV. This implied recovery of parasympathetic and baroreceptor function. Return of sympathovagal interaction was further supported by the suppression of Cheyne-Stokes type HRV as detected by Wigner-Ville distribution. CONCLUSIONS: Long-term beta-blocker therapy for advanced congestive heart failure upwardly regulates the autonomic nervous interaction in synchrony with the evolution of cardiac function performance.