Network pharmacological and molecular docking verification of the mechanism of Osteoking in preventing deep vein thrombosis of lower limb.

OBJECTIVE: The aim of this study was to predict the mechanism of Osteoking in preventing deep vein thrombosis (DVT) of the lower limb by network pharmacology and molecular docking. MATERIALS AND METHODS: The relevant active components and targets of Osteoking were collected through the TCMSP database, and the relevant disease targets of DVT were collected through the GeneCards, OMIM, and DisGeNET databases. The intersecting gene targets of Osteoking and DVT were obtained using Venny 2.1.0 software. PPI network construction and core target selection using Cytoscape 3.9.0 software. The Metascape database was used for GO and KEGG enrichment analysis of relevant targets. Finally, the molecular docking of the main active components and key targets was carried out. RESULTS: There are 361 potential targets and 71 core targets of Osteoking in preventing deep vein thrombosis of the lower limb. Signal pathways are involved in various diseases such as cancer, diabetic complications, atherosclerosis, and more. Some of the most common pathways include AGE-RAGE signaling pathway and Calcium signaling pathway. Molecular docking results showed that the main active components of Osteoking had relatively stable binding activities with the key targets. CONCLUSIONS: Osteoking can play a role through multiple targets and multiple signal pathways to prevent the formation of deep venous thrombosis of the lower limb after fracture.

Wagyu-Angus cross improves meat tenderness compared to Angus cattle but unaffected by mild protein restriction during late gestation.

For the spring-calving beef herds, late gestation coincides with winter and early spring, when cows are dependent on feed supplements with low quality hay, which is hard to meet their nutrient requirements. However, the effects of deficiencies of metabolizable protein intake during late gestation on offspring beef quality are unclear. Wagyu cattle have excellent marbling, and insemination with Wagyu vs Angus semen is a practical option for beef producers to improve beef quality. To test, Angus cows (621 ±â€¯73 kg) were selected and randomly separated into two groups. Each group was inseminated with either Angus or Wagyu semen. During the last 90 days of gestation, cows in each group were further separated and received either a low protein diet (85% of the NRC metabolizable protein requirement), which was a low quality hay-based diet common in northwestern region of the U.S., or an adequate protein diet (108% NRC requirement). All progeny was managed together and harvested at a final BW of 576.5 ±â€¯16.6 kg. Wagyu-sired offspring had higher marbling scores and quality grades than Angus (P < 0.01). Protein supplementation did not affect Slice Shear Force (SSF) in either breeds (P = 0.60). However, Wagyu-sired cattle had lower SSF than Angus-sired (P < 0.01). In addition, Wagyu-sired cattle had higher intramuscular fat (P < 0.05) and total collagen content (P < 0.05), but Angus-sired had greater mature collagen cross-links, as shown by higher contents of Pyridinoline (P < 0.01) and Ehrlich Chromogen (P < 0.01). Consistently, the mRNA expression of enzymes catalyzing collagen cross-linking was higher in Angus-sired offspring, including Plod 1 (P < 0.05), Plod 2 (P = 0.08), and P4Hα 2 (P < 0.01). In conclusion, Wagyu-sired cattle had greater tenderness and marbling score compared to Angus-sired, which was associated with lower collagen cross-links. Feeding mature grass hay-based diet with relatively low protein content during late gestation had no major effect on beef quality of subsequent cattle.

Cataract surgery is associated with a reduced risk of dementia: a nationwide population-based cohort study.

BACKGROUND AND PURPOSE: Our purpose was to determine the association of cataract surgery with subsequent development of dementia in older adults with newly diagnosed cataract. METHODS: By using data from Taiwan National Health Insurance Research Database (NHIRD), a population-based cohort study including 491 226 subjects aged 70 or older with first-time diagnosis of cataract coded from 2000 to 2009 was conducted. After matching cataract patients receiving cataract surgery with cataract patients without receiving cataract surgery for age, sex, index date, Charlson Comorbidity Index score, interval between first coding of cataract diagnosis and index date, hypertension and diabetes mellitus, 113 123 patients in each cohort were enrolled. The main outcome measure was newly diagnosed dementia coded by neurologists or psychiatrists more than 365 days after cataract surgery. Incidence rate and hazard ratio of dementia were compared between the cataract surgery and cataract diagnosis cohorts. RESULTS: The incidence rate of dementia was 22.40 per 1000 person-years in the cataract surgery cohort and 28.87 per 1000 person-years in the cataract diagnosis cohort. The rate of dementia was significantly lower in the cataract surgery group (hazard ratio 0.77, 95% confidence interval 0.75-0.79, P < 0.001). Female gender (P < 0.001) and a shorter interval between the date of first coding of a cataract diagnosis and the date of cataract surgery (P = 0.009) were significantly associated with a lower incidence rate of dementia. CONCLUSION: In an NHIRD cohort of Taiwanese aged 70 years and older with a diagnosis of cataract, patients undergoing cataract surgery were associated with a reduced risk of subsequent dementia compared with those without cataract surgery.

Effects of areca nut extract on the apoptosis pathways in human neutrophils.

BACKGROUND AND OBJECTIVE: Areca nut, a major component in area quid, possesses genotoxic and carcinogenic activities. Areca nut extract (ANE) may affect the defensive functions of neutrophils. Recent studies suggest that areca nut chewing is associated with a higher prevalence of periodontal disease as a result of the detrimental effects of ANE on the host defense system. This study examined the effects of ANE on the apoptosis pathways in human neutrophils. MATERIAL AND METHODS: Apoptosis/necrosis of neutrophils was determined using flow cytometry. Proteins involved in the apoptosis pathway were determined using western blotting analysis. RESULTS: The results indicated that ANE reduced early apoptosis, but increased the primary necrosis of neutrophils. ANE may arrest neutrophils in the G0/G1 phase and reduce the apoptotic hypodiploid DNA contents. The levels of cleaved forms of poly(ADP-ribose) polymerase, and of caspase-3 and caspase-8 were decreased by treatment with ANE. Moreover, glycogen synthase kinase-3 alpha/beta may be involved in the ANE-modulated effects of neutrophils. CONCLUSION: Areca nut may regulate death pathways in neutrophils. This may be one mechanism by which areca nut compromises the periodontal health of areca nut chewers.

Areca nut extracts increased expression of inflammatory cytokines, tumor necrosis factor-alpha, interleukin-1beta, interleukin-6 and interleukin-8, in peripheral blood mononuclear cells.

BACKGROUND AND OBJECTIVE: Cytokines represent a central role in inflammatory tissue destruction and regulate the immune responses that may govern the progression of periodontal diseases. This study investigated the effects of areca nut extracts on the expression of inflammatory cytokines, tumor necrosis factor-alpha, interleukin-1beta, interleukin-6 and interleukin-8 in peripheral blood mononuclear cells. The role of oxidative stress of areca nut extracts was also examined using curcumin. MATERIAL AND METHODS: The expression of cytokines in peripheral blood mononuclear cells treated with extracts of ripe areca nut or extracts of tender areca nut was analyzed using enzyme-linked immunosorbent assay and reverse transcription-polymerase chain reaction. RESULTS: Both extracts of ripe areca nut (< or = 40 microg/mL) and extracts of tender areca nut significantly enhanced the production of tumor necrosis factor-alpha and interleukin-1beta in peripheral blood mononuclear cells in a dose-dependent and time-dependent manner. The kinetics of mRNA expression of both cytokines was also enhanced by areca nut extracts. The stimulatory effects of areca nut extracts on the secretion of tumor necrosis factor-alpha, interleukin-1beta, interleukin-6 and interleukin-8 and on the mRNA expression of tumor necrosis factor-alpha, interleukin-1beta and interleukin-6 at 4 h of incubation were reduced by curcumin (20-50 microm). However, the level of interleukin-8 transcripts was not affected by curcumin. Moreover, interleukin-1beta induction by extracts of tender areca nut, but not by extracts of ripe areca nut, was weakened by 10 microm curcumin. The inhibitory effects of curcumin may vary with different cytokines and with different areca nut extract treatments. CONCLUSION: The complex cytokine profile induced by areca nut extracts-treated peripheral blood mononuclear cells implied the possibility of enhanced local inflammation and altered immune functions by the areca chewing habit. The inhibitory effects of curcumin on cytokine expression suggested that oxidative stress might be involved in areca nut extracts-associated immune alteration.

Calcium and vitamin D intake influence bone mass, but not short-term fracture risk, in Caucasian postmenopausal women from the National Osteoporosis Risk Assessment (NORA) study.

UNLABELLED: The impact of calcium and vitamin D intake on bone density and one-year fracture risk was assessed in 76,507 postmenopausal Caucasian women. Adequate calcium with or without vitamin D significantly reduced the odds of osteoporosis but not the risk of fracture in these Caucasian women. INTRODUCTION: Calcium and vitamin D intake may be important for bone health; however, studies have produced mixed results. METHODS: The impact of calcium and vitamin D intake on bone mineral density (BMD) and one-year fracture incidence was assessed in 76,507 postmenopausal Caucasian women who completed a dietary questionnaire that included childhood, adult, and current consumption of dairy products. Current vitamin D intake was calculated from milk, fish, supplements and sunlight exposure. BMD was measured at the forearm, finger or heel. Approximately 3 years later, 36,209 participants returned a questionnaire about new fractures. The impact of calcium and vitamin D on risk of osteoporosis and fracture was evaluated by logistic regression adjusted for multiple covariates. RESULTS: Higher lifetime calcium intake was associated with reduced odds of osteoporosis (peripheral BMD T-score < or =-2.5; OR = 0.80; 95% CI 0.72, 0.88), as was a higher current calcium (OR = 0.75; (0.68, 0.82)) or vitamin D intake (OR = 0.73; 95% CI 0.0.66, 0.81). Women reported 2,205 new osteoporosis-related fractures. The 3-year risk of any fracture combined or separately was not associated with intake of calcium or vitamin D. CONCLUSIONS: Thus, higher calcium and vitamin D intakes significantly reduced the odds of osteoporosis but not the 3-year risk of fracture in these Caucasian women.

Effects of diets supplemented with organic acids and nucleotides on growth, immune responses and digestive tract development in weaned pigs.

Sixty-eight (Experiment 1, 46 days feeding) and sixteen (Experiment 2, 21 days feeding) 21-days-old weaned pigs were allotted to four dietary treatments including control, 0.6% organic acids (OA), 0.1% nucleotides (NA) and 0.6% OA plus 0.1% NA for determining the dietary effects. In Experiment 1, OA enhanced peripheral blood mononuclear cells proliferation on day 28 and 46. The plasma immunoglobulin (Ig) A level was elevated by OA (p < 0.06) and NA (p < 0.07), respectively. In Experiment 2, NA increased plasma IgM level, and had an interactive effect with OA on ileal Peyer's patches and mesenteric lymph node lymphocyte proliferation, bile and plasma IgA levels, and jejunal crypt depth. NA elevated gastric pepsin and jejunal alkaline phosphatase activities, however, decreased ileal aminopeptidase N, sucrase or maltase activity. These results suggest that OA and NA have synergistically enhanced the gut-associated lymphocyte responses and NA modulates the digestive tract development of weaned pigs.

Areca nut extracts-activated secretion of leukotriene B4, and phosphorylation of p38 mitogen-activated protein kinase and elevated intracellular calcium concentrations in human polymorphonuclear leukocytes.

BACKGROUND AND OBJECTIVE: Polymorphonuclear leukocytes are the major source of leukotriene B4, which is synthesized via the 5-lipoxygenase pathway. Activation of the 5-lipoxygenase pathway is regulated by intracellular calcium and the phosphorylation of p38 mitogen-activated protein kinase (MAPK). The impact of areca nut extracts on the biosynthesis of leukotriene B4 by human polymorphonuclear leukocytes was evaluated, and some of the possible mechanisms underlying the responses were examined. MATERIAL AND METHODS: Polymorphonuclear leukocytes were treated with various concentrations of areca nut extracts. The concentrations of leukotriene B4 released into the supernatants were evaluated using enzyme immunoassay. The phosphorylation of p38 MAPK was monitored using immunoblotting, and the cytosolic calcium kinetics were assessed fluorometrically using Fura-2. RESULTS: Exposure of polymorphonuclear leukocytes to areca nut extracts led to a dose-dependent increase in the production of leukotriene B4, with levels peaking at 30 min and decreasing thereafter. Areca nut extracts enhanced the phosphorylation of p38 MAPK, an enzyme known to activate 5-lipoxygenase. Incubation with areca nut extracts also resulted in a rapid elevation of intracellular calcium concentrations in polymorphonuclear leukocytes. The induction of leukotriene B4 by areca nut extracts was suppressed with the p38 MAPK inhibitor, SB203580, or with the intracellular calcium chelator, BAPTA-AM. CONCLUSION: The interaction of areca nut extracts with polymorphonuclear leukocytes activated the arachidonic acid metabolic cascade. Incubation of polymorphonuclear leukocytes with areca nut extracts resulted in the activation of intracellular events, such as phosphorylation of p38 MAPK and Ca2+ mobilization, involved in the release of pro-inflammatory lipid mediators. The results of this study emphasize the potential importance of polymorphonuclear leukocytes as a source of leukotriene B4, which may modulate the inflammatory response in areca chewers.

Hypertension and impaired glycine handling in mice lacking the orphan transporter XT2.

A family of orphan transporters has been discovered that are structurally related to the Na(+)-Cl(-)-dependent neurotransmitter transporters, including the dopamine transporter. One member of this family, the mouse XT2 gene, is predominantly expressed in the kidney and has 95% homology to rat ROSIT (renal osmotic stress-induced Na(+)-Cl(-) organic solute cotransporter). To study the physiological functions of this transporter, we generated XT2-knockout mice by gene targeting. XT2(-/-) mice develop and survive normally with no apparent abnormalities. To attempt to identify potential substrates for XT2, we screened urine from XT2-knockout mice by high-pressure liquid chromatography and mass spectrometry and found significantly elevated concentrations of glycine. To study glycine handling, XT2(+/+) and XT2(-/-) mice were injected with radiolabeled glycine, and urine samples were collected to monitor glycine excretion. After 2 h, XT2(-/-) mice were found to excrete almost twice as much glycine as the XT2(+/+) controls (P = 0.03). To determine whether the absence of the XT2 transporter affected sodium and fluid homeostasis, we measured systolic blood pressure by computerized tail-cuff manometry. Systolic blood pressure was significantly higher in XT2(-/-) mice (127 +/- 3 mmHg) than in wild-type controls (114 +/- 2 mmHg; P < 0.001). This difference in systolic blood pressure was maintained on high and low salt feeding. To examine whether the alteration in blood pressure and the defect in glycine handling were related, we measured systolic blood pressure in the XT2(-/-) mice during dietary glycine supplementation. Glycine loading caused systolic blood pressure to fall in the XT2(-/-) mice from 127 +/- 3 to 115 +/- 3 mmHg (P < 0.001), a level virtually identical to that of the wild-type controls. These data suggest that the XT2 orphan transporter is involved in glycine reabsorption and that the absence of this transporter is sufficient to cause hypertension.

Effects of areca nut extracts on the functions of human neutrophils in vitro.

Aqueous extracts of ripe areca nut without husk (ripe ANE) and fresh and tender areca nut with husk (tender ANE) were examined for their effects on the defensive functions of human neutrophils. Exposure of peripheral blood neutrophils to ripe ANE and tender ANE inhibited their bactericidal activity against oral pathogens, including Actinobacillus actinomycetemcomitans and Streptococcus mutans, in a dose-dependent manner. At the concentrations tested, ripe and tender ANEs did not significantly affect the viability of neutrophils as verified by their ability to exclude trypan blue dye. However, both ANEs inhibited the production of bactericidal superoxide anion by neutrophils as measured by cytochrome c reduction. Moreover, the ripe ANE inhibited neutrophils more effectively than did tender ANE. Arecoline, a major alkaloid of areca nut, only exhibited an inhibitory effect on the functions of neutrophils when high concentrations were used. Therefore, arecoline could not be used to explain the inhibitory effects observed for ANEs. In conclusion, our results demonstrated that ripe and tender ANEs reduced the antibacterial activity and the superoxide anion production of neutrophils. This effect may contribute to a less efficient elimination of bacteria from the periodontal environment. Inhibition of the antimicrobial functions of neutrophils may alter the microbial ecology of the oral cavity, and this may be one possible mechanism by which areca nut compromises the oral health of users of areca nut products.

Nutritional deficiencies in a patient with glycogen storage disease type Ib.

The current mainstay of treatment in glycogen storage disease type I (GSD I) is dietary management that includes providing a frequent source of glucose to prevent hypoglycaemia. To ensure compliance, routine follow-up by a health care team, including a dietitian, experienced in the treatment of GSD is necessary. We describe an adolescent patient with GSD Ib in good metabolic control who was admitted with a 3-month history of weakness, depression, vomiting, decreased appetite and a 11.4-kg weight loss. He had a recent onset of unsteady gait, inability to write, and sore mouth. After an extensive work-up, the patient was found to have vitamin B12, folate, iron and other nutritional deficiencies, which explained his symptoms. The patient improved within 72 h of initiation of total parenteral nutrition and therapeutic doses of deficient micronutrients, with a complete recovery in 2 months. Dietary restrictions, dependence on non-food products (e.g. cornstarch in GSD I), and social and developmental issues place individuals with metabolic disorders at a high risk for developing an array of nutritional deficiencies. This case highlights the importance of both close follow-up of the metabolic control and close monitoring of growth and nutritional intake in individuals with inborn errors of metabolism. This case also illustrates the importance of daily supplementation with appropriate multivitamins, calcium and other minerals needed to meet the Recommended Dietary Allowances (RDAs) in these patients.

Human lung cancer antigens recognized by autologous antibodies: definition of a novel cDNA derived from the tumor suppressor gene locus on chromosome 3p21.3.

Serological analysis of a recombinant lung cancer cDNA expression library with the autologous patient serum led to the isolation of 20 clones representing 12 different genes: 4 of these were known genes, and the other 8 were previously unknown genes. Of the four known genes, aldolase A (NY-LU-1), previously shown to be overexpressed in lung cancer, was most frequently isolated. The other three genes were annexin XI, human HIV Rev-interacting protein Rip-1, and the human homologue of the ATP-binding arsA component of the bacterial arsenite transporter, all of which are known to be widely expressed in human tissues. Among the eight unknown genes, of most interest was NY-LU-12. Cloning of full-length NY-LU-12 showed that this cDNA was derived from the same gene as g16, a partially sequenced gene that mapped to the lung cancer tumor suppressor gene locus on chromosome 3p21. The reported g16 sequence, however, was significantly shorter (2433 versus 3591 bp). As a result of alternate splicing and subsequent frameshift, the reported g16 protein is 603 amino acids shorter than the NY-LU-12 product (1123 residues) at its COOH terminus and would therefore lack the epitopes recognized by the autologous serum. Analysis of the putative NY-LU-12 protein sequence predicted that it is a nuclear zinc finger protein with two RNA-binding domains, and Southern analysis showed that this gene is partially deleted in the lung cancer line NCI-H740 but not in nine other lung cancer lines. Screening of normal and cancer patient sera showed anti-NY-LU-12 seroreactivity in 2 of 21 allogeneic lung cancer patients but not in 24 patients with other tumors or in 16 sera from healthy donors. Comparison of NY-LU-12 cDNA from Lu15 tumor and normal lung tissue by DNA sequencing and/or single-strand conformation polymorphism analysis showed no evidence of mutation. Considering the high frequency of 3p21 alterations in lung cancer and the fact that the tumor suppressor gene or genes in this locus have not been identified, additional studies on the NY-LU-12 gene and its product are warranted.

[Clinical study on effect of combined treatment of fuchunpian with radiotherapy on nasopharyngeal carcinoma].

The study based on the clinical prospective trial of 60 cases of nasopharyngeal carcinoma treated with combined treatment of radiotherapy and Fuchunpian in our hospital from September, 1988 to January, 1990. Results of clinical data of 5 years follow-up showed that Fuchunpian not only couldn't enhance the radiosensitivity of patients, but also increase the blood metastatic potency, the metastatic rate of patients treated with Fuchunpian (36.7%) was 2.67 times higher than that without it (10.0%). Therefore, it was considered that use Fuchunpian as a routine either administrated alone or combined with radiotherapy in treatment of nasopharyngeal carcinoma is not suitable.

Subunit interaction enhances enzyme activity and stability of sweet potato cytosolic Cu/Zn-superoxide dismutase purified by a His-tagged recombinant protein method.

The coding region of copper/zinc-superoxide dismutase (Cu/Zn-SOD) cDNA from sweet potato, Ipomoea batatas (L.) Lam. cv. Tainong 57, was introduced into an expression vector, pET-20b(+). The Cu/Zn-SOD purified by His-tagged technique showed two active forms (dimer and monomer). The amount of proteins of dimer and monomer appeared to be equal, but the activity of dimeric form was seven times higher than that of monomeric form. The enzyme was dissociated into monomer by imidazole buffer above 1.0 M, acidic pH (below 3.0), or SDS (above 1%). The enzyme is quite stable. The enzyme activity is not affected at 85 degrees C for 20 min, in alkali pH 11.2, or in 0.1 M EDTA and also quite resistant to proteolytic attack. Dimer is more stable than monomer. The thermal inactivation rate constant kd calculated for the monomer at 85 degrees C was 0.029 min-1 and the half-life for inactivation was about 28 min. In contrast, there is no significant change of dimer activity after 40 min at 85 degrees C. The enzyme dimer and monomer retained 83% and 58% of original activity, respectively, after 3 h incubation with trypsin at 37 degrees C, while those retained 100% and 31% of original activity with chymotrypsin under the same condition. These results suggest subunit interaction might change the enzyme conformation and greatly improve the catalytic activity and stability of the enzyme. It is also possible that the intersubunit contacts stabilize a particular optimal conformation of the protein or the dimeric structure enhances catalytic activity by increasing the electrostatic steering of substrate into the active site.

An experimental trial of artemether in treatment of Pneumocystis carinii in immunosuppressed rats.

An immunosuppressed rat model was established by injecting cortisone acetate 25 mg/rat twice a week for 4 weeks and 12.5 mg/rat for another 2 weeks subcutaneously. A development of Pneumocystis carinii pneumonia (PCP) was found at the end of the 6th week in all rats. These rats were injected intramuscularly with artemether at 100 mg/kg once a day for 5 consecutive days. All rats were necropsied at the end of the 8th week. The lung impression smears were stained with Gomori's stain, and Pneumocystis carinii cysts were counted. The ultrastructural changes of trophozoite, precyst and cyst were investigated by transmission electron microscopy on the 7th day after treatment.

[One year follow-up study of the recovery of adrenal insufficiency induced by formulated herb drugs].

Previous studies have found that taking formulated herb drugs may reduce the serum cortisol level which may result in an adrenal insufficiency. We suspect that this effect is induced by corticosteroids artificially mixed in formulated herb drugs. The objectives of this study were to determine the time course of serum cortisol and plasma ACTH (adrenocorticotropic hormone) levels, and whether pituitary-adrenal function recovers after quitting formulated herb drugs for a period of one year. Forty eight subjects with an initial serum cortisol level smaller than 10.7 micrograms/dL due to the intake of formulated herb drugs were recruited. They were tested for serum cortisol and plasma ACTH levels at 08:00 6, 9 and 12 months after quitting formulated herb drugs, respectively. The diagnosis of adrenal insufficiency was confirmed by an ACTH test at 9 months and 12 months after quitting the formulated herb drugs. The follow-up rates ranged from 63% to 71%. The 08:00 serum cortisol levels at the initial test, 6 months, 9 months, and 12 months were 4.4 +/- 0.5 micrograms/dL, 6.6 +/- 0.8 micrograms/dL, 6.6 +/- 0.7 micrograms/dL, 6.2 +/- 0.8 micrograms/dL, respectively, (interpersonal p = 0.0001, intrapersonal p = 0.0004, repeated measures ANOVA test.) The 08:00 plasma ACTH levels at the initial test, 6 months, 9 months and 12 months were 33.8 +/- 6.4 pg/mL, 67.6 +/- 16.8 pg/mL, 21.0 +/- 3.2 pg/mL, 16.3 +/- 2.2 pg/mL, respectively (interpersonal P = 0.0001, intrapersonal P = 0.0003, repeated measures ANOVA test.) The statistical significance was the same after logarithmic transformation of the ACTH levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency: diagnosis by acylcarnitine analysis in blood.

Medium-chain acyl-coenzyme A dehydrogenase (MCAD) deficiency is a disorder of fatty acid catabolism, with autosomal recessive inheritance. The disease is characterized by episodic illness associated with potentially fatal hypoglycemia and has a relatively high frequency. A rapid and reliable method for the diagnosis of MCAD deficiency is highly desirable. Analysis of specific acylcarnitines was performed by isotope-dilution tandem mass spectrometry on plasma or whole blood samples from 62 patients with MCAD deficiency. Acylcarnitines were also analyzed in 42 unaffected relatives of patients with MCAD deficiency and in other groups of patients having elevated plasma C8 acylcarnitine, consisting of 32 receiving valproic acid, 9 receiving medium-chain triglyceride supplement, 4 having multiple acyl-coenzyme A dehydrogenase deficiency, and 8 others with various etiologies. Criteria for the unequivocal diagnosis of MCAD deficiency by acylcarnitine analysis are an elevated C8-acylcarnitine concentration (> 0.3 microM), a ratio of C8/C10 acylcarnitines of > 5, and lack of elevated species of chain length > C10. These criteria were not influenced by clinical state, carnitine treatment, or underlying genetic mutation, and no false-positive or false-negative results were obtained. The same criteria were also successfully applied to profiles from neonatal blood spots retrieved from the original Guthrie cards of eight patients. Diagnosis of MCAD deficiency can therefore be made reliably through the analysis of acylcarnitines in blood, including presymptomatic neonatal recognition. Tandem mass spectrometry is a convenient method for fast and accurate determination of all relevant acylcarnitine species.

Antiarrhythmic action of naloxone. Suppression of picrotoxin-induced cardiac arrhythmias in the rat.

The antiarrhythmic properties of the opiate antagonist naloxone have been reported in a variety of models of arrhythmia. To determine the generality and the possible central involvement of its antiarrhythmic activity, the effects of naloxone were assessed against cardiac arrhythmias induced by intravenous bolus injections of picrotoxin. Naloxone at doses of 0.33 and 1 mg/kg significantly reduced the incidence and severity of picrotoxin-induced arrhythmias in a dose-related manner, without alteration of blood pressure and heart rate. The results demonstrate the antiarrhythmic efficacy of naloxone in an additional animal model. They further suggest that the antiarrhythmic actions of naloxone may be mediated by the central nervous system via both the autonomic and GABAergic pathways.