Clearance of carbapenemase-producing Enterobacteriaceae (CPE) carriage: a comparative study of NDM-1 and KPC CPE.

OBJECTIVES: The aim of this study was to compare clearance rates and related characteristics of patients carrying KPC-producing carbapenemase-producing Enterobacteriaceae (CPE) with those of patients carrying NDM-1-producing CPE. METHODS: From November 2010 to October 2016, consecutive patients whose clinical or surveillance cultures yielded CPE were prospectively identified and followed in a 2700-bed tertiary referral hospital. CPE control protocols included strict single-room isolation, contact precautions and weekly surveillance cultures. CPE clearance was defined as three or more consecutive CPE-negative cultures without relapse. We compared patients carrying NDM-1 CPE and KPC and those with and without clearance. The time to CPE clearance or discharge was assessed using the Kaplan-Meier method and NDM-1 CPE and KPC CPE groups were compared. RESULTS: A total of 147 patients carrying CPE, 106 with NDM-1 and 41 with KPC, were included in the study. At the time of hospital discharge, 12 of the 106 patients carrying NDM-1 CPE were clear of CPE, whereas none of the KPC CPE patients were (NDM-1, 11.3% (12/106) versus KPC, 0% (0/41), p 0.02). There was no significant association between CPE clearance and factors such as an immunocompromised condition, antibiotic usage, or species of colonizing organism. Among 40 patients who were readmitted, CPE non-clearance was significantly higher in patients carrying KPC CPE (NDM-1, 36.7% (11/30) versus KPC, 80.0% (8/10), p 0.03). CONCLUSIONS: Compared with NDM-1 CPE patients, patients carrying KPC CPE had a significantly lower probability of clearance during hospitalization. Furthermore, KPC CPE carriage persisted for a substantial period of time following patient discharge.

Comparison of the efficacies of oral iron and pramipexole for the treatment of restless legs syndrome patients with low serum ferritin.

BACKGROUND AND PURPOSE: It is not clear which is preferred between iron supplement and a dopamine agonist in the treatment of restless legs syndrome (RLS) with iron deficiency. The efficacies of oral iron supplementation and pramipexole for treatment of RLS with low-normal serum ferritin (15-50 ng/ml) were compared. METHODS: Thirty RLS patients who took either oral iron or pramipexole for 12 weeks and were followed at 2, 4, 8 and 12 weeks after treatment commencement were enrolled. Severities of RLS symptoms were assessed using the international RLS study group rating scale for severity (IRLS) at every visit. Treatment response was defined as a decrease in IRLS score of at least 50% from baseline. RESULTS: The 30 subjects were assigned equally to an iron or pramipexole group. At baseline, IRLS scores and serum ferritin levels were similar between these two groups. After 12 weeks, IRLS scores were lower than those at baseline in both groups (iron -9.1 ± 7.07, P < 0.001; pramipexole -8.7 ± 8.31, P = 0.001) and similar between the two groups. Changes in IRLS scores from baseline were similar between the two groups at each visit. The response rates of the groups were identical at 46.7%. CONCLUSIONS: Pramipexole was not different from oral iron in terms of efficacy and improvement speed in RLS patients with a low-normal serum ferritin, but response rate of either oral iron or pramipexole alone was moderate. Some proportion of RLS patients with iron deficiency might benefit from combined use of oral iron and dopamine agonists.

Effects of heme oxygenase system on the cyclooxygenase in the primary cultured hypothalamic cells.

Endogenous carbon monoxide (CO) shares with nitric oxide (NO) a role as a putative neural messenger in the brain. Both gases are believed to modulate CNS function via an increase in cytoplasmic cGMP concentrations secondary to the activation of soluble guanylate cyclase (sGC). Recently CO and NO were proposed as a possible mediator of febrile response in hypothalamus. NO has been reported to activate both the constitutive and inducible isoform of the cyclooxygenase (COX). Thus, we investigated whether CO arising from heme catabolism by heme oxygenase (HO) is involved in the febrile response via the activation of COX in the hypothalamus. PGE2 which is a final mediator of febrile response released from primary cultured hypothalamic cells was taken as a marker of COX activity. PGE2 concentration was measured with EIA kits. Exogenous CO (CO-saturated medium) and hemin (a substrate and potent inducer of HO) evoked an increase in PGE2 release from hypothalamic cells, and these effects were blocked by methylene blue (an inhibitor of sGC). And membrane permeable cGMP analogue, dibutyryl-cGMP elicited significant increases in PGE2 release. These results suggest that there may be a functional link between HO and COX enzymatic activities. The gaseous product of hemin through the HO pathway, CO, might play a role through the modulation of the COX activity in the hypothalamus.

Antioxidant lignans from Machilus thunbergii protect CCl4-injured primary cultures of rat hepatocytes.

Eleven lignans (1-11) were isolated from the CH2Cl2 fraction of the bark of Machilus thunbergii Sieb. et Zucc. (Lauraceae). These were identified as (-)-acuminatin (1), (-)-isoguaiacin (2), meso-dihydroguaiaretic acid (3), (+)-galbacin (4), (-)-sesamin (5), (+)-galbelgin (6), machilin A (7), machilin G (8), licarin A (9), and nectandrin A (10) and B (11). Primary cultures of rat hepatocytes were co-incubated for 90 min with the hepatotoxin CCl4 and each of the 11 lignans (50 microM). Hepatoprotective activity was determined by measuring the level of glutamic pyruvic transaminase released into the medium from the primary cultures of rat hepatocytes. (-)-Acuminatin, (-)-isoguaiacin and meso-dihydroguaiaretic acid all significantly reduced the level of glutamic pyruvic transaminase released. Further investigation revealed that these three compounds significantly preserved the levels and the activities of glutathione, superoxide dismutase, glutathione peroxidase and catalase. (-)-Acuminatin, (-)-isoguaiacin and meso-dihydroguaiaretic acid also ameliorated lipid peroxidation as demonstrated by a reduction of malondialdehyde production. These results suggest that (-)-acuminatin, (-)-isoguaiacin and meso-dihydroguaiaretic acid exert diverse hepatoprotective activities, perhaps by serving as potent antioxidants.

Isolation and characterization of immune-related genes from the fall webworm, Hyphantria cunea, using PCR-based differential display and subtractive cloning.

Following injection of bacteria into the hemocoel of the fall webworm, Hyphantria cunea, several inducible genes were identified and characterized using PCR-based differential display (DD-PCR) and subtractive cloning. Ten immune-related cDNA clones (Hdd1, Hdd2, Hdd3, Hdd11, Hdd13, Hdd15, Hdd17, Hdd23, Hs106, Hs302) were isolated and characterized. The deduced amino acid sequence of Hdd2 was shown to be a member of the copper, zinc superoxide dismutase (Cu-Zn SOD) family. The H. cunea Cu-Zn SOD is novel in that it is up-regulated following a bacterial challenge and has a putative signal peptide suggesting its secretion and involvement in the insect immune response. Hdd3 was found to encode a new member of the serpin (serine protease inhibitor) family. The putative lectin corresponding to Hdd15 is of a different kind in that it has two lectin C domains in a single molecule. These two lectin C domains show significant homology to the lectin C domain of Periplaneta lipopolysaccharide binding protein (LPS-BP). Three cloned genes, Hdd17, Hs106 and Hs302, encode a homologue to Bombyx mori Gram negative binding protein, a hemolin-like protein and a attacin-like protein, respectively. The deduced amino acid sequences from Hdd11 showed weak homology with a Locusta migratoria hemolymph protein. On the contrary, Hdd1, Hdd13 and Hdd23 did not reveal any significant homology with known proteins. All of the 10 genes were clearly inducible by E. coli and M. luteus injection. Injection of distilled water only slightly induced mRNA levels. Comparison of temporal mRNA expression following E. coli injection showed three types of expression patterns.

The prevention of carbon tetrachloride-induced hepatotoxicity in mice by alpha-hederin: inhibiton of cytochrome P450 2E1 expression.

The protective effects of alpha-Hederin on carbon tetrachloride-induced hepatotoxicities were investigated in mice. Pretreatment with alpha-Hederin prior to the administration of carbon tetrachloride significantly prevented the increase in serum alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) activity and lipid peroxidation in a dose dependent manner. Hepatic glutathione levels and glutathione-S-transferase activities were not affected by pretreatment with alpha-Hederin alone but pretreatment with alpha-Hederin protects carbon tetrachloride-induced depletion of hepatic glutathione levels. The effects of alpha-Hederin on the cytochrome P450 (P450) 2E1, the major isozyme involved in carbon tetrachloride bioactivation were investigated. alpha-Hederin markedly decreased the P450 2E1-specific activities of p-nitrophenol and aniline hydroxylation in a dose-dependent manner. Consistent with these observations, the P450 2E1 expressions were also decreased, as determined by immunoblot analysis. These results demonstrate that treatment of mice with alpha-Hederin decreases the expression and activities of P450 2E1 enzyme, and reduces biotransformation of carbon tetrachloride, and diminished carbon tetrachloride-induced liver injury.

Isolation and characterization of the cDNA encoding the prophenoloxidase of fall webworm, hyphantria cunea.

Two kinds of cDNA clones encoding prophenoloxidases (ProPO; zymogen of phenoloxidase (monophenol, L-dopa: oxygen oxydoreductase, EC 1.14.18.1)) were isolated by polymerase chain reaction (PCR) followed by screening of cDNA library that was prepared from whole larvae of the fall webworm, Hyphantria cunea (Lepidoptera, Arctiidae). The cDNAs encode 681 and 697 amino acids with molecular masses of 78.2 and 80.2 kDa, respectively. Deduced amino acid sequence homology between the two H. cunea ProPOs are only 49% whereas the homology against other insect ProPOs ranged from about 40 to 72%. The phylogenic analysis showed that the insect ProPOs are grouped mainly into two families. A putative proteolytic cleavage site for enzyme activation was identical to other insect ProPOs. The conserved copper binding sites were 84-62% homologous to arthropod ProPOs. Two additional highly conserved regions were found in the carboxy terminal. Furthermore, like other insect prophenoloxidases, hydrophobic signal peptide sequences were absent in the deduced ProPOs from H. cunea. Southern blot analysis indicated that the H. cunea ProPO1 is present as a single copy in the genome. Northern blot analysis showed that the expression of the ProPO genes were concentrated in mid-instar larvae, but were much lower in other developmental stages.

Terminal differentiation and senescence in the human melanocyte: repression of tyrosine-phosphorylation of the extracellular signal-regulated kinase 2 selectively defines the two phenotypes.

Melanocytes are pigmented cells distributed in humans in several organs like the epidermis, the leptomeninges, the eye, and the inner ear. Epidermal melanocytes, whether derived from adult or neonatal skin, proliferate well in a medium supplemented with phorbol esters and other mitogens before they undergo senescence. Potent cAMP inducers like cholera toxin are also growth promoters for neonatal melanocytes but only transient growth stimulators for cells derived from adults. We used this cellular system to delineate biochemical pathways involved in proliferation and in terminal differentiation. Here we show that after a period of 4-8 wk of sustained proliferation in the presence of cholera toxin, the adult melanocytes became round, flat, and enlarged. These changes were associated with terminal growth and preceded by a five- to sixfold increase in cAMP levels and an 8- to 10-fold increase in melanin content. The simultaneous addition of phorbol esters and cholera toxin did not prevent cells from reaching terminal differentiation. Identified targets for phorbol esters are protein kinase C (PKC) and the mitogen-activated kinases (MAPKs), also called extracellular signal-regulated kinases (ERKs). PKC was found to be similarly regulated in proliferating and in terminally differentiated melanocytes. Proliferating melanocytes in early or late passage showed identical activation of the kinase ERK2. This kinase was rapidly phosphorylated upon phorbol 12-myristate 13-acetate (PMA) addition and specifically accumulated in the nucleus of the cells, whereas in unstimulated cells it had a perinuclear distribution. In contrast, senescent and terminally differentiated cells were unable to phosphorylate tyrosine residues of the ERK2 gene product in spite of presenting normal amounts of ERK2 protein. In addition, ERK2 did not show the nuclear accumulation observed in proliferating melanocytes after PMA activation and remained localized in the perinuclear area. These results demonstrate that senescent and terminally differentiated melanocytes share a common block in a critical pathway thought to integrate multiple intracellular signals transmitted by various second messengers and specifically prevent the continuation of the signal transduction cascade initiated by PMA activation of PKC.

Subcorneal pustular dermatosis treated with phototherapy.

A 12-year-old boy had a 5-year history of recurrent generalized dermatoses with scales, crusts, and pustules. Histologic findings showed subcorneal blisters filled with polymorphonuclear leukocytes typical of subcorneal pustular dermatosis. Dapsone and prednisolone with a topical fluocinolone acetonide did not produce improvement. The skin lesions cleared completely after 11 exposures of UV-B three times a week. After 8 months of follow-up, there has been no recurrence.