George Kremenopoulos
Aristotle University of Thessaloniki
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Journal of Clinical Microbiology | 2003
Emmanuel Roilides; Evangelia Farmaki; Joanna Evdoridou; Andrea Francesconi; Miki Kasai; Joanna Filioti; Maria Tsivitanidou; Danai Sofianou; George Kremenopoulos; Thomas J. Walsh
ABSTRACT From June to July 1998, two episodes of Candida tropicalis fungemia occurred in the Aristotle University neonatal intensive care unit (ICU). To investigate this uncommon event, a prospective study of fungal colonization and infection was conducted. From December 1998 to December 1999, surveillance cultures of the oral cavities and perinea of the 593 of the 781 neonates admitted to the neonatal ICU who were expected to stay for >7 days were performed. Potential environmental reservoirs and possible risk factors for acquisition of C. tropicalis were searched for. Molecular epidemiologic studies by two methods of restriction fragment length polymorphism analysis and two methods of random amplified polymorphic DNA analysis were performed. Seventy-two neonates were colonized by yeasts (12.1%), of which 30 were colonized by Candida albicans, 17 were colonized by C. tropicalis, and 5 were colonized by Candida parapsilosis. From December 1998 to December 1999, 10 cases of fungemia occurred; 6 were due to C. parapsilosis, 2 were due to C. tropicalis, 1 was due to Candida glabrata, and 1 was due to Trichosporon asahii (12.8/1,000 admissions). Fungemia occurred more frequently in colonized than in noncolonized neonates (P < 0.0001). Genetic analysis of 11 colonization isolates and the two late blood isolates of C. tropicalis demonstrated two genotypes. One blood isolate and nine colonization isolates belonged to a single type. The fungemia/colonization ratio of C. parapsilosis (3/5) was greater than that of C. tropicalis (2/17, P = 0.05), other non-C. albicans Candida spp. (1/11, P = 0.02), or C. albicans (0/27, P = 0.05). Extensive environmental cultures revealed no common source of C. tropicalis or C. parapsilosis. There was neither prophylactic use of azoles nor other risk factors found for acquisition of C. tropicalis except for total parenteral nutrition. A substantial risk of colonization by non-C. albicans Candida spp. in the neonatal ICU may lead to a preponderance of C. tropicalis as a significant cause of neonatal fungemia.
The Journal of Pediatrics | 1995
Vassiliki Soubasi; George Kremenopoulos; Elissavet Diamanti; Chaido Tsantali; Kosmas Sarafidis; Dimitrios Tsakiris
OBJECTIVE Treatment with recombinant human erythropoietin (rHuEPO) stimulates erythropoiesis and reduces the need for transfusions in hospitalized preterm infants. The aim of our study was to follow very low birth weight infants after the initial 6 weeks of rHuEPO treatment. DESIGN AND METHODS We randomly assigned 97 very low birth weight infants with a gestational age of 31 weeks or less and birth weight of 1500 gm or less to receive rHuEPO, 300 units/kg per week (erythropoietin (EPO) 300, n = 33), rHuEPO, 750 units/kg per week (EPO 750; n = 28), or no treatment (control, n = 36). The rHuEPO was administered from the first week of life for 6 weeks. After EPO therapy was discontinued, 75 neonates were followed weekly until discharge and at 3, 6, and 12 months of age. RESULTS Mean numbers (+/- SD) of packed erythrocyte transfusions per patient from the time rHuEPO therapy was discontinued until discharge were 0.38 +/- 0.64 (EPO 300), 0.23 +/- 0.52 (EPO 750), 0.9 +/- 1.1 (control) (p < 0.05 in both EPO groups vs control). Mean reticulocyte counts at the sixth week were 6% +/- 2.2% (EPO 300), 6.9% +/- 2.2% (EPO 750), and 3.1% +/- 2.6% (control) in the three groups (p < 0.01 in both EPO groups vs control), and at the eighth week were 4.7% +/- 2.8% (EPO 300), 5.4% +/- 2.7% (EPO 750), and 2.6% +/- 2.2% (control) (p < 0.01 in both EPO groups vs control). Serum ferritin levels were significantly higher at the sixth week, and the percentage of hemoglobin F was significantly lower at 6, 8, and 10 weeks in the control group versus EPO groups. At 3, 6, and 12 months of age, there were no differences in reticulocytes, ferritin, HbF, and growth among groups. CONCLUSION Preterm infants who received rHuEPO had a normal pattern of erythropoiesis after the drug was discontinued. These data provide strong evidence that the anemia of prematurity is the result of a transient developmental abnormality in EPO production.
Pediatric Research | 1993
Vassiliki Soubasi; George Kremenopoulos; Elisabeth Diamandi; Chaido Tsantali; Dimitrios Tsakiris
ABSTRACT: To assess whether erythropoietin (EPO) treatment is safe and reduces the need for transfusion, we randomized 44 preterm infants to an EPO group and a comparable control (CON) group. EPO 150 U/kg was given s.c. twice weekly for 6 wk from the 1st wk of life. Hematologic parameters, transfusion requirements, and growth were followed during therapy and for 6 mo thereafter. To better assess in which neonates EPO treatment was effective, we classified retrospectively the EPO and CON groups into uncomplicated neonates (EPO A: n = 9, birth weight = 1247 ± 126 g, gestational age = 29.8 ± 1.5 wk; CON A: n = 7, birth weight = 1217 ± 145 g, gestational age = 29.9 ± 1.5 wk) and neonates requiring artificial ventilation (EPO B: n = 16, birth weight = 1169 ± 249 g, gestational age = 28.1 ± 2 wk; CON B: n = 12, birth weight = 1173 ± 215 g, gestational age = 28.3 ± 2 wk). There were significant differences in reticulocytes between both uncomplicated and ventilated neonates in the EPO group compared with respective control groups. However, the need for transfusion was significantly less in the uncomplicated EPO group (EPO A: 0.44 ± 0.73 versus CON A: 1.28 ± 0.75, p< 0.05) but not in the neonates on ventilation (EPO B: 8.25 ± 5 versus CON B: 7.75 ± 3.7). In conclusion, early EPO administration reduces the need for transfusion in uncomplicated premature neonates. Although stimulation of erythropoiesis was apparent in both uncomplicated and complicated neonates, the end-result of increased need for transfusion in complicated neonates was related to altered indication of transfusion. These infants probably require further or longer EPO administration after weaning from ventilation and improvement of clinical condition.
Brain Research | 2004
Evangelia Spandou; Stamatia Papoutsopoulou; Vassiliki Soubasi; George Karkavelas; Constantina Simeonidou; George Kremenopoulos; Olympia Guiba-Tziampiri
Erythropoietin (EPO), known for its role in erythroid differentiation, has been suggested to have non-hematopoietic functions in the brain, especially during development. In the present study, we investigated the expression of erythropoietin and erythropoietin receptor (EPOR) in the developing rat brain following hypoxia-ischemia. Seven-day-old rats underwent unilateral, permanent carotid artery ligation followed by 1 h of hypoxia, and their brains were examined immediately, 24 h or 4 days after hypoxia-ischemia. RT-PCR and Western blot analysis revealed that hypoxia-ischemia only marginally affected EPO expression. Immunohistochemical study of brains 4 days after hypoxia showed that 60 min of hypoxia (resulting in cortical infarction and severe neuronal loss in other regions) led to the increased EPO immunoreactivity, especially in the boundaries of the damaged cerebral cortex, associated with astrocytosis. In contrast, EPOR was dramatically upregulated within 24 h after hypoxia-ischemia. These results suggest that there is a rapid response of EPOR to the hypoxic-ischemic stimulus, which seems to precede that of EPO, leading to the hypothesis that the EPO/EPOR system is implicated in the processes of neuroprotection from hypoxia-ischemia.
Pediatric Neurology | 1995
Dimitrios I. Zafeiriou; Ioannis Tsikoulas; George Kremenopoulos
To clarify reflex profiles in the first year of life in connection with categories of neurologic abnormality, eight primitive reflexes (i.e., the palmar grasp reflex, the plantar grasp reflex, the Galant response, the asymmetric tonic neck reflex, the suprapubic extensor reflex, the crossed extensor reflex, the Rossolimo reflex, and the heel reflex) were prospectively examined in 204 high-risk infants, of whom 58 developed cerebral palsy, 22 had developmental retardation, and 124 were normal at follow-up examination at 2 years of age. The change in the retention time of reflex activity for each of these reflexes was characteristic for each category or type of neurologic abnormality: retention of palmar grasp reflex, suprapubic extensor reflex, crossed extensor reflex, Rossolimo reflex, and heel reflex in spastic cerebral palsy, as well as retention of plantar grasp reflex, Galant reflex, and asymmetric tonic neck reflex in athetoid cerebral palsy and somewhat weaker retention of these reflexes in developmental retardation (statistical significance P < .001 compared with normally developed patients). These characteristic changes imply that a presumptive diagnosis can be made in neurologically high-risk infants by examination of the primitive reflexes, which are of specific significance among the other neurologic criteria within the first year of life.
Pediatric Infectious Disease Journal | 2002
Paraskevi Panagopoulou; Joanna Evdoridou; Evangelia Bibashi; Joanna Filioti; Danai Sofianou; George Kremenopoulos; Emmanuel Roilides
Trichosporon asahii causes white piedra, an infection of hair shafts and onychomycosis in immunocompetent patients, as well as various localized or disseminated invasive infections in immunodeficient hosts. We describe a 26-week gestation 890-g vaginally delivered female neonate who had severe respiratory distress syndrome and on the sixth day of life developed Klebsiella pneumoniae sepsis. At the same time two blood cultures were positive for T. asahii. The neonate was also colonized with T. asahii in the pharynx and perineum. The infant was successfully treated with conventional amphotericin B.
Neonatology | 2000
Vassiliki Soubasi; George Kremenopoulos; Chaido Tsantali; Persefoni Savopoulou; Constantine Mussafiris; Maria Dimitriou
The aim of this study was to investigate the effect of recombinant human erythropoietin (rHu-EPO) on oxygen affinity and adequate oxygen delivery to the tissues of stable premature infants. 36 very-low-birth-weight infants were randomly assigned to either receive rHu-EPO (200 units/kg every other day) or not, and both groups were supplemented with iron, folic acid and vitamin E. Arterial blood gases, oxygen saturation, complete blood counts, fetal haemoglobin, 2,3-diphosphoglycerate (2,3-DPG) and blood lactate were analysed weekly, from the 1st week till discharge. Patients in the two groups were comparable. There was a trend in increasing lactate values towards the 4th to 5th weeks of life, which did not reach statistical significance. There was no correlation between lactate values and the studied variables (pH, BE, oxygen saturation). In 35 transfusions, pre- and 24 h post-transfusion blood lactate status was studied. In 23 of them, a decrease in post-transfusion lactate was noticed, whilst an increased post-transfusion level was shown in 10 cases and no change in 2 cases. The mean pre-transfusion lactate value was significantly higher than the post-transfusion one (24.04 ± 11.9 mg/dl before and 16.27 ± 8.5 mg/dl after transfusion; p = 0.0025). In both groups there was a steady rise in 2,3-DPG concentration over the period of study, and the 2,3-DPG values at the end of our study were significantly increased in the rHu-EPO group (rHu-EPO 5.98 ± 0.9, control 4.84 ± 0.7; p = 0.04). In conclusion, the use of rHu-EPO did not affect blood lactate levels compared to the control group. Regarding oxygen affinity, it seems that rHu-EPO causes a shift of the oxy-haemoglobin dissociation curve to the right. This is a previously unreported effect of rHu-EPO and its clinical use may, thus, confer to preterm babies an added advantage.
Brain & Development | 1998
Dimitrios I. Zafeiriou; Ioannis Tsikoulas; George Kremenopoulos; E. Kontopoulos
To clarify the predictive value of the seven more commonly used postural reactions (PR) in the 1st year of life regarding the diagnosis of cerebral palsy (CP), we prospectively examined 204 high-risk infants of whom 58 developed CP, 22 had developmental retardation (DR) and 124 were normal at follow-up at 3 years of age. Abnormalities of five or more PR from the 1st month of life were correlated with spastic CP, while five or six abnormal PR were also correlated with athetoid CP. Three or less abnormal PR correlated with a normal outcome. All seven PR tested were significantly abnormal in children with spastic CP from the 1st month compared to normal children. Athetoid children demonstrated abnormalities of the Peiper-Isbert (P-I) reaction and Vojta reaction from the 1st month and of the vertical, horizontal and Collis vertical suspension from the 3rd month. Children with DR had significantly abnormal Collis horizontal and Collis vertical suspension, Vojta reaction and traction response from the 1st month and Peiper-Isbert reaction from the 3rd month. Ataxic children demonstrated significantly abnormal traction response from the 1st month, Collis horizontal reaction from the 7th month and Peiper-Isbert reaction from the 11th month. We conclude that the examination of PR is a useful quantitative and qualitative diagnostic screening tool for high-risk infants from the 1st month of life.
Neonatology | 2001
Elias Gioulekas; Michael Goutzioulis; Christos Farmakis; Vasiliki Drossou; George Kremenopoulos; John Tsiouris; Emmanuel Roilides
The effects of recombinant macrophage-colony stimulating factor (M-CSF) on antifungal activities of monocytes (MNC) from healthy neonates and adults against Candida albicans were compared. Pretreatment of adult and neonatal MNC with 15 ng/ml of M-CSF for 4 days significantly increased superoxide anion (O2–) production in response to phorbol myristate acetate. While M-CSF-treated MNC from adults produced significantly higher O2– in response to Candida blastoconidia, M-CSF-treated neonatal MNC did not show a similar response. Further, M-CSF significantly enhanced phagocytosis of C. albicans by adult MNC but not by neonatal MNC. While M-CSF enhances antifungal activities of adult MNC against C. albicans, it does not appear to affect anticandidal function of neonatal MNC.
Brain & Development | 1997
Dimitrios I. Zafeiriou; Ioannis Tsikoulas; George Kremenopoulos; Eleftherios E. Kontopoulos
We read with great interest the article by Futagi et al. [ 1 ] about the prognosis of infants with ankle clonus within the first year of life. We would like to add our own experience in this field. As part of a prospective study regarding the prognostic significance of primitive reflex profiles in the early diagnosis of cerebral palsy (CP) [2], ankle clonus was prospectively examined in a series of 204 high-risk infants at 1, 3, 5, 7, 9 and 11 months of life. At follow-up at 3 years of age, 58 children developed CP (49 spastic CP, 7 athetoid CP and 2 ataxic CP), 22 had developmental retardation without motor disturbance (DR) and 124 children had a normal development. Ankle clonus was elicited using the same method as described by Futagi et al. [1] and was defined as present only when the reactivity was more than 10 beats. The results are summarized in Table 1. The presence of ankle clonus was significantly higher in children with spastic CP already from the third month of life (P < 0.001) compared to normal children. There was no significant difference at any age between athetoid and normal children regarding ankle clonus, while children with DR demonstrated a statistical significance (P < 0.05) compared to normal children, only at the first month of life. It is also worth mentioning that although 78 out of 124 normal children (62.9%) exhibited ankle clonus at the first month of life, it almost disappeared at the fifth month of life (4.5% of the children). The above results suggest that ankle clonus is often present in high-risk infants at the first year of life, especially at the first month. However, only its presence beyond the third month of life should be interpreted as a Table 1