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61.
To analyze interleukin-2-dependent immunoregulatory function in hepatitis B virus infection and in other forms of viral hepatitis, levels of soluble interleukin-2 receptors (sIL-2R) were measured by an enzyme-linked assay in sera from patients with acute and chronic viral hepatitis of different etiology. Increased sIL-2R levels were detected in the early phase of acute hepatitis type A and type B, but not during acute non-A, non-B hepatitis. Among 46 patients with chronic hepatitis B virus infection, levels of sIL-2R were significantly increased only in cases with chronic active hepatitis, while they were about normal in chronic persistent hepatitis or in healthy carriers of the infection. These differences were independent of virus replication, being maintained when patients were stratified according to HBeAg/anti-HBe status and to serum HBV-DNA. Nine patients with chronic active hepatitis type B and high sIL-2R levels at presentation were followed prospectively for two to eight years, and in HBeAg -positive patients, the behavior of receptor levels closely paralleled disease activity. These results, which may reflect increased shedding of IL-2R by activated T lymphocytes in patients with active destruction of HBV infected hepatocytes, indicate the usefulness and potential prognostic importance of serum slL-2R determination in patients with chronic viral hepatitis. Patients with chronic non-A, non-B hepatitis had much lower sIL-2R levels, although their liver disease was similar to hepatitis B cases, suggesting that different pathogenetic mechanisms operate in these patients.  相似文献   
62.
PURPOSE: We ascertained and reviewed acute health events occurring in 2003 among patients age 18 and greater with well-defined single gene, chromosomal, and selected multifactorial conditions within the Marshfield Epidemiologic Study Area. METHODS: Of 47,077 adult Marshfield Epidemiologic Study Area Central cohort members, 1,831 (3.9%) had been given at least one of 71 ICD-9 codes appropriate for genetic diagnoses of interest. Physician review narrowed this to 591 (1.3%) validated patients for the study. Of the 591, 527 (89.2%) patients registered 6,849 visits, which were manually reviewed to delineate acute, relevant health events in the urgent care and primary care provider setting. RESULTS: A total of 244 acute relevant health events among 126 patients corresponding to 58 different genetic conditions were observed. Acute relevant health events corresponded to 3.4% of the total health events in patients identified with genetic problems. Categories of genetic conditions with the highest frequencies of acute relevant health events included chromosomal and microdeletion syndromes (21.3%), hematologic disorders (11.5%), muscular dystrophies (8.6%), and connective tissue disorders (10.2%). CONCLUSIONS: These data have multiple applications and implications in addressing the natural history, long-term medical needs and financial impact of adult patients with genetic conditions.  相似文献   
63.
Compounds structurally related to the known antimicrobial drug linezolid were selected in order to evaluate the influence of electron-withdrawing properties and altered geometric features as a result of the N-substituent modification. After a preliminary study of molecular modeling, cinnamoyl-, pyridin- and pyrimidinoxazolidin-2-ones were synthesized. None of the new compounds showed antibacterial activity.  相似文献   
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Tubulin, the major structural component of microtubules, is a target for the development of anticancer agents. Two series of 1,5-diaryl substituted 1,2,3,4-tetrazoles were concisely synthesized, using a palladium-catalyzed cross-coupling reaction, and identified as potent antiproliferative agents and novel tubulin polymerization inhibitors that act at the colchicine site. SAR analysis indicated that compounds with a 4-ethoxyphenyl group at the N-1 or C-5 position of the 1,2,3,4-tetrazole ring exhibited maximal activity. Several of these compounds also had potent activity in inhibiting the growth of multidrug resistant cells overexpressing P-glycoprotein. Active compounds induced apoptosis through the mitochondrial pathway with activation of caspase-9 and caspase-3. Furthermore, compound 4l significantly reduced in vivo the growth of the HT-29 xenograft in a nude mouse model, suggesting that 4l is a promising new antimitotic agent with clinical potential.  相似文献   
66.
Strategy, Management and Health Policy
Enabling Technology, Genomics, Proteomics Preclinical Research Preclinical Development Toxicology, Formulation Drug Delivery, Pharmacokinetics Clinical Development Phases I‐III Regulatory, Quality, Manufacturing Postmarketing Phase IV
3,5‐Di‐t‐butylcatechol (DTCAT) stimulates the rat skeletal muscle sarcoplasmic reticulum ryanodine receptor (RyR). In the present study, its effects on the contractile response of diaphragm preparation were characterized using electrically stimulated phrenic nerve–diaphragm preparations and diaphragm strips. DTCAT reduced, concentration‐dependently, twitch contraction of the phrenic nerve–diaphragm preparation evoked by both direct and indirect stimulation and increased spontaneous tone. Twitch amplitude reduction was irreversible, while the increase of spontaneous tone was only partially reversible upon DTCAT washout. In diaphragm strips, caffeine > 4‐chloro‐m‐cresol >> 3,5‐diisopropylcatechol ? ryanodine > DTCAT enhanced spontaneous tone, whereas quercetin reduced it with all the compounds reducing twitch amplitude. DTCAT‐induced contracture was partly dependent on extracellular Ca2+ influx and antagonized by a Cd2+/La3+ mixture. In intact skeletal muscle preparations, DTCAT behaved as a RyR agonist.  相似文献   
67.
The main aim of the study was to identify the critical periods of susceptibility for itraconazole-mediated teratogenesis in the mouse. Pregnant ICR (CD-1) mice received a single oral administration of itraconazole at 50 mg/kg b.w., 150 mg/kg b.w. or 250 mg/kg b.w. on gestation day 8, 9, 10, 11 or 12. Control animals were administered with vehicle on gestation days 8-12. The gestational outcome was evaluated near term, on gestation day 18. Treatment-related morphological findings, as they can be evaluated by external, visceral and skeletal examination, mainly included cleft palate, limb defects and axial skeletal malformations. Cleft palate and limb defects resulted after single exposures between gestation days 9 and 11, with a tendency toward maximal response on gestation day 10. Significant incidences of axial skeletal defects were seen exclusively on gestation days 8 and 9. Exposure on gestation day 12 did not yield significant teratogenic responses. Cleft palate was the most sensitive teratogenic response, being the only developmental lesion associated to exposure to itraconazole at 150 mg/kg b.w.  相似文献   
68.

Background

Sustained antibody levels are a hallmark of immunity against many pathogens, and induction of long-term durable antibody titers is an essential feature of effective vaccines. Heterologous prime-boost approaches with vectors are optimal strategies to improve a broad and prolonged immunogenicity of malaria vaccines.

Results

In this study, we demonstrate that the heterologous prime-boost regimen Ad35-CS/BCG-CS induces stronger immune responses by enhancing type 1 cellular producing-cells with high levels of CSp-specific IFN-γ and cytophilic IgG2a antibodies as compared to a homologous BCG-CS and a heterologous BCG-CS/CSp prime-boost regimen. Moreover, the heterologous prime-boost regimen elicits the highest level of LLPC-mediated immune responses.

Conclusion

The increased IFN-γ-producing cell responses induced by the combination of Ad35-CS/BCG-CS and sustained type 1 antibody profile together with high levels of LLPCs may be essential for the development of long-term protective immunity against liver-stage parasites.  相似文献   
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70.

Improving the conditions of poor traditional societies is a standard goal of development policies. The definition of ‘improvement’ requires a previous definition of values, that is to say, ‘better’ or ‘worse’ can change according to the parameters used to optimize the system. Different scientific disciplines generally focus on different levels of analysis: the individual, the socio‐economic, or the environmental level. Consequently, optimization parameters derived from single disciplines are not holistic in assessing development. System energy analysis can provide a way to describe the interaction among individuals, human societies and natural processes, that bridges the different levels of analysis.

This paper investigates the relationship between nutrition and energy efficiency in farming systems based on human labor. By describing the energetic budget of a society, trade‐offs can be assessed between a better diet at individual level, and the consequent decrease in the conversion ratio of energy input into applied power at societal level (more elderly, larger body size, dramatic increase of energetic cost for nutritional calories). The relationship between energy efficiency and nutrition in the process of societal development is also addressed.  相似文献   
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