PubMed Health⌕ Search

Biomedical subjects

D Miron

Publications and source records attributed to D Miron.

At least 37 records · Page 2Linked to original sources
PubMed2000

Purification and characterization of bifunctional lysine-ketoglutarate reductase/saccharopine dehydrogenase from developing soybean seeds.

Both in mammals and plants, excess lysine (Lys) is catabolized via saccharopine into alpha-amino adipic semialdehyde and glutamate by two consecutive enzymes, Lys-ketoglutarate reductase (LKR) and saccharopine dehydrogenase (SDH), which are linked on a single bifunctional polypeptide. To study the control of metabolite flux via this bifunctional enzyme, we have purified it from developing soybean (Glycine max) seeds. LKR activity of the bifunctional LKR/SDH possessed relatively high K(m) for its substrates, Lys and alpha-ketoglutarate, suggesting that this activity may serve as a rate-limiting step in Lys catabolism. Despite their linkage, the LKR and SDH enzymes possessed significantly different pH optima, suggesting that SDH activity of the bifunctional enzyme may also be rate-limiting in vivo. We have previously shown that Arabidopsis plants contain both a bifunctional LKR/SDH and a monofunctional SDH enzymes (G. Tang, D. Miron, J.X. Zhu-Shimoni, G. Galili [1997] Plant Cell 9: 1-13). In the present study, we found no evidence for the presence of such a monofunctional SDH enzyme in soybean seeds. These results may provide a plausible regulatory explanation as to why various plant species accumulate different catabolic products of Lys.

Amino Acid Sequence↗
PubMed2000

Age-related seroprevalence of Cryptosporidium in northern Israel.

BACKGROUND: Two recent studies found that the prevalence of cryptosporidiosis among children in Israel was 3.4-7.4%. OBJECTIVES: To assess the cumulative infection rate by testing immunoglobulin A and G seroprevalence for Cryptosporidium in children and adults in Israel. PATIENTS AND METHODS: The seroprevalence of IgA and IgG anti-Cryptosporidium antibodies was determined by an enzyme-linked immunosorbent assay procedure in a group of 163 healthy children and adults. RESULTS: The overall seroprevalence rates for IgG, IgA, both IgA and IgG, and any immunoglobulin were 12.6%, 23%, 30% and 65.6% respectively. Half the children under the age of 12 years were already infected, with seroprevalence increasing to 95.6% in those over age 13 (P < 0.05). Seropositivity for IgG or IgA did not significantly increase with age. CONCLUSIONS: These results indicate that a large percentage of healthy children and adults in northern Israel have been infected with Cryptosporidium, and at early ages.

Adult↗
PubMed2000

[Thrombocytopenic purpura as sole manifestation of brucellosis in children].

Thrombocytopenic purpura associated with brucellosis has rarely been described in children. The thrombocytopenic purpura is usually part of the array of manifestations of brucellosis, such as fever, malaise, arthralgia, arthritis, hepatosplenomegaly and lymphadenopathy. We describe a 4-year-old girl in whom severe thrombocytopenic purpura was the only manifestation of brucellosis and resolved after appropriate antibiotic therapy. We conclude that brucellosis should be included in the differential diagnosis of thrombocytopenic purpura in areas endemic for brucellosis, and when there is a history of exposure to infected food products.

Anti-Bacterial Agents↗
PubMed1999

Effectiveness of a nationwide infant immunization program against Haemophilus influenzae b. The Israeli Pediatric Bacteremia and Meningitis Group.

An ongoing nationwide prospective surveillance program for invasive H. influenzae b (Hib) disease in Israel enabled us to study the effectiveness of a national infant Hib immunization program, which included all infants born since January 1994. The vaccine used was Hib polysaccharide conjugated to outer membrane protein complex of Neisseria meningitidis b (PRP-OMPC). For the cohort born during the 3 years since January 1994, the vaccine effectiveness was 94.9% for all invasive Hib diseases and 96.6% for meningitis. The efficacy in fully immunized subjects was 98.7 and 99.5%, respectively. A herd immunity effect could be observed, since a reduction in cases also occurred among infants too young to be immunized. No increase in invasive cases caused by S. pneumoniae and N. meningitidis was observed during the study period. This is the first report outside North America and Western Europe that demonstrates a nationwide extensive reduction of invasive Hib disease within a short time of the introduction of Hib conjugate vaccines to the infant immunization program.

Bacterial Outer Membrane Proteins↗
PubMed1999

Safety and immunogenicity of Shigella sonnei and Shigella flexneri 2a O-specific polysaccharide conjugates in children.

O-specific polysaccharide conjugates of shigellae were safe and immunogenic in young adults, and a Shigella sonnei conjugate conferred protection [1-3]. Shigellosis is primarily a disease of children; therefore, the safety and immunogenicity of S. sonnei and Shigella flexneri 2a conjugates were studied in 4- to 7-year-old children. Local and systemic reactions were minimal. The first injection of both conjugates elicited significant rises in geometric mean levels of serum IgG only to the homologous lipopolysaccharide (LPS) (S. sonnei, 0.32-8.25 ELISA units [EU]; S. flexneri 2a, 1.15-20.5 EU; P<.0001). Revaccination at 6 weeks induced a booster response to S. flexneri 2a LPS (20.5-30.5 EU, P=.003). Six months later, the geometric mean levels of IgG anti-LPS for both groups were higher than the prevaccination levels (P<.0001). Similar, but lesser, rises were observed for IgM and IgA anti-LPS. The investigational Shigella conjugates were safe and immunogenic in children and merit evaluation of their efficacy.

Antibodies, Bacterial↗
PubMed1997

[Pyogenic liver abscess in children].

2 children with pyogenic liver abscesses were hospitalized during the past 2 years. A 6-year-old boy had high fever and hepatomegaly, and a large liver abscess was found in the right hepatic lobe. Streptococcus milleri was isolated from the pus. Treatment with a combination of prolonged drainage of the abscess and antibiotic therapy was successful. A 4-month-old girl who had prolonged fever was found to have osteomyelitis of 3 thoracic vertebrae and 2 liver abscesses in the right lobe. She was treated successfully with broad spectrum antibiotics. Additional workup revealed that she had chronic granulomatous disease.

Anti-Bacterial Agents↗
PubMed1997

Regulation of lysine catabolism through lysine-ketoglutarate reductase and saccharopine dehydrogenase in Arabidopsis.

In plant and mammalian cells, excess lysine is catabolized by a pathway that is initiated by two enzymes, namely, lysine-ketoglutarate reductase and saccharopine dehydrogenase. In this study, we report the cloning of an Arabidopsis cDNA encoding a bifunctional polypeptide that contains both of these enzyme activities linked to each other. RNA gel blot analysis identified two mRNA bands-a large mRNA containing both lysine-ketoglutarate reductase and saccharopine dehydrogenase sequences and a smaller mRNA containing only the saccharopine dehydrogenase sequence. However, DNA gel blot hybridization using either the lysine-ketoglutarate reductase or the saccharopine dehydrogenase cDNA sequence as a probe suggested that the two mRNA populations apparently are encoded by the same gene. To test whether these two mRNAs are functional, protein extracts from Arabidopsis cells were fractionated by anion exchange chromatography. This fractionation revealed two separate peaks-one containing both coeluted lysine-ketoglutarate reductase and saccharopine dehydrogenase activities and the second containing only saccharopine dehydrogenase activity. RNA gel blot analysis and in situ hybridization showed that the gene encoding lysine-ketoglutarate reductase and saccharopine dehydrogenase is significantly upregulated in floral organs and in embryonic tissues of developing seeds. Our results suggest that lysine catabolism is subject to complex developmental and physiological regulation, which may operate at gene expression as well as post-translational levels.

Amino Acid Sequence↗
PubMed1996

A 1-year trial of nasal mupirocin in the prevention of recurrent staphylococcal nasal colonization and skin infection.

BACKGROUND: The usefulness of nasal mupirocin in preventing recurrent staphylococcal nasal colonization and skin infection has been examined in immunodeficient patients and in healthy staphylococcal carriers but not in immunocompetent staphylococcal carriers who experience recurrent skin infections. We studied 34 such patients. METHODS: After an initial 5-day course of nasal mupirocin ointment for all patients, 17 patients continued to apply a 5-day course of nasal mupirocin every month for 1 year, and the other 17 patients applied a placebo ointment. Nasal cultures were obtained monthly, and all episodes of skin infection were recorded. RESULTS: The overall number of positive nasal cultures was 22 in the mupirocin group and 83 in the placebo group (P < .001), and the number of skin infections was 26 and 62, respectively (P < .002). Eight of the 17 mupirocin-treated patients but only 2 in the placebo group remained free of positive staphylococcal nasal cultures. One of the 10 patients who were free of colonization during the 12-month treatment period had skin infections, in contrast to all 24 of the patients with positive cultures (P < .01). Staphylococci resistant to mupirocin were observed in 1 patient. No adverse effects were reported. CONCLUSIONS: A monthly application of mupirocin ointment in staphylococcal carriers reduces the incidence of nasal colonization, which in turn lowers the risk of skin infection.

Administration, Topical↗
PubMed1995

Oral ciprofloxacin for treatment of infection following nail puncture wounds of the foot.

From January 1990 to December 1993, 23 adults were hospitalized at our institution for treatment of foot infections that occurred following nail puncture wounds. All 23 patients had cellulitis, and 14 had signs of osteochondritis on a roentgenogram or a 99mTc bone scan. After undergoing surgical intervention that consisted of debridement, drainage of the pus, and exploration of the bones, patients received intravenous ciprofloxacin (400 mg b.i.d.) for 24 hours, followed by an oral regimen (750 mg b.i.d.). Nine patients with cellulitis received oral therapy for 7 days, and the 14 patients with osteochondritis received oral therapy for 14 days. Isolates that were recovered included Pseudomonas aeruginosa (18 patients) and Staphylococcus aureus (2 patients); one patient had a mixed infection, and in two cases no pathogens were recovered. All of the isolates were susceptible to ciprofloxacin. All patients were cured, and none had reinfection. Our results show that foot infection following a nail puncture wound may be treated with oral ciprofloxacin (750 mg b.i.d.) for 7-14 days, provided that surgery is performed first.

Administration, Oral↗