Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Umbilical cord blood (UCB) is an attractive potential alternative to bone marrow (BM) as a source of hematopoietic progenitor cells since the number of progenitors in UCB is similar or even greater than that in normal BM. It was the aim of the present study to analyze the degree of immaturity of UCB progenitor cells. UCB mononuclear (MNC) and/or CD34+ cells were tested for surface antigen phenotype, expression of cytokines receptor, effect of stem cell factor (SCF) on colony growth, resistance to mafosfamide and replating potential. We have found that 34.9 +/- 3.4% and 77.9 +/- 2.6% of UCB CD34+ cells did not express CD38 and CD45RA antigens, respectively, suggesting that UCB contains a high proportion of immature progenitor cells. By means of three-color analysis, the receptor for SCF was detected on the majority of the CD34+ HLA-DR+ subpopulation; in fact, 81.8% +/- 4.3% of CD34+ HLA-DR+ cells were defined as SCF(low) and 8.1 +/- 1.5% as SCF(high). Colony growth of MNC and CD34+ cells was enhanced by the addition of SCF to methylcellulose mixture, resulting in a statistically significant increase in CFU-GM and CFU-GEMM but not in BFU-E numbers. UCB progenitor cells showed a higher resistance to mafosfamide treatment, in comparison to BM; the addition of SCF to the culture medium resulted in a statistically significant increase in mafosfamide concentration required to inhibit 95% of colony growth (P < or = 0.05). Moreover, as shown by single colony transfer assays, the presence of SCF in primary cultures promoted a significantly higher replating potential for both untreated (42 +/- 3.3% vs 21 +/- 4.6%, P < or = 0.018) and mafosfamide-treated samples (62 +/- 5.6% vs 44 +/- 6.1%, P < or = 0.018). In conclusion, UCB is a source of progenitor cells with immature characteristics in terms of surface antigen expression, distribution of SCF receptor, resistance to mafosfamide and replating potential. Therefore, UCB progenitor cells represent an ideal candidate population for experimental programs involving gene transfer and ex vivo stem cell expansion.
Leukemia 1997 Dec
PMID:Biologic and phenotypic analysis of early hematopoietic progenitor cells in umbilical cord blood. 944 33

First trimester procedures have been associated with perinatal lung function abnormalities that may suggest subsequent respiratory problems. Our aim was, therefore, to assess the impact of first trimester invasive procedures [early amniocentesis (EA) and chorion villus sampling (CVS)] on respiratory morbidity in very young children. A questionnaire was issued to parents of 439 EA and 453 CVS (subjects), and 435 controls (their mothers had undergone no invasive procedures) when their children were one year old. Data were also obtained from diary cards issued to a subset of 278 of the EA, 262 of the CVS, and 264 of the control infants followed prospectively. Functional residual capacity (FRC) was measured at a median age of 5 months (range: 0.25-24) in 159 children whose mothers had undergone EA, 168 following CVS and in 165 controls. Analysis of the one-year questionnaire demonstrated an excess of symptomatic infants in the EA group (31%) compared to the CVS (22%; P < 0.01) and control groups (17%; P < 0.01). Findings from the prospective follow-up study confirmed those results and also demonstrated an increase in chest-related hospital admissions in the EA group (3%) compared to the controls (0.4%; P < 0.05). Logistic regression analysis revealed that positive symptom status related significantly to EA and CVS interventions (P < 0.0001), bottle feeding (P < 0.001), parental smoking (P < 0.01), a family history of atopy (P < 0.01), and immaturity (P < 0.01). In the control group, FRC correlated best with weight (r = 0.92). The mean FRC of the EA and CVS groups was higher than that of the controls (P < 0.01). A higher proportion of children had an FRC two standard deviations above the controls' mean in the EA group (n = 14) compared to the CVS group (n = 3; P < 0.01). The symptomatic infants tended to have higher FRCs than the asymptomatic children. We conclude that first trimester procedures are associated with increased respiratory morbidity in very young children.
Pediatr Pulmonol 1997 Dec
PMID:First trimester invasive procedures: effects on symptom status and lung volume in very young children. 944 33

Studies of endoepithelial-triggered reflexes, such as nasal respiratory reflexes, are difficult to carry out in humans without a non-traumatic and reliable stimulation device. The air puff stimulator described allows us to deliver air puffs of brief duration at various intensities, frequencies, and temperatures. The stimulation is non-traumatizing and non-nociceptive. We have successfully used it in animals as a source of specific stimuli to enable us to study central and peripheral neuronal responses evoked by activation of endonasal dynamically sensitive receptors. Immunohistochemical studies of the c-fos expression evoked during sneezing elicited by air puffs provided additional evidence for the specificity of this particular stimulation technique. We suggest that the use of such a non-traumatizing air puff stimulator could be extended to human studies. It might be particularly useful in developmental studies of endoepithelial-triggered reflexes such as those respiratory reflexes whose immaturity at birth can be life-threatening.
J Neurosci Methods 1997 Dec 01
PMID:An improved mechanical air puff stimulator that allows activation of a variety of endoepithelial receptors and is suitable for the study of reflexes in animals and humans. 948 87

The epidermal growth factor receptor (EGF-R) is perhaps the best studied member of tyrosine kinase receptors. Its inactivation by homologous recombination results in three different phenotypes ranging from peri-implantation lethality to postnatal lethality. The mildest form of EGF-R inactivation leads to epithelial immaturity and postnatal death due to respiratory failure and necrotizing enterocolitis-like lesions in the intestine. The defects seen in this 'postnatal lethality phenotype' manifest in the classical EGF-responsive organs (skin, intestine) and organs undergoing branching morphogenesis during development (lung, kidney, mammary gland, pancreas and prostate), and thus accord with the concept of EGF family members being important epithelial mitogens. The respiratory failure of the EGF-R (-/-) mice results from impaired branching of the alveolar tree and leads to decreased surface for gas exchange. Overall, the lung phenotype bears similarity to respiratory distress syndrome and bronchopulmonary dysplasia--the most common complications of prematurity in humans. Intestinal changes seen in the EGF-R (-/-) mice vary in severity, the end-point being severe mucosal lesions and necroses. These findings resemble those seen in necrotizing enterocolitis of premature babies, a serious intestinal problem in the neonate. Although deficient EGF-R function is not the reason for these prematurity-associated diseases it may nevertheless exacerbate them. Potential usage of EGF transforming growth factor-alpha in clinical work is discussed.
Ann Med 1997 Dec
PMID:Epidermal growth factor receptor in mice and men--any applications to clinical practice? 956 19

We report on the first case of X-linked recessive myotubular myopathy (MTM1) coinciding with Duchenne muscular dystrophy (DMD). The muscle biopsy specimens of the patient show only the characteristic findings of MTM1, without the findings of DMD. We theorize that this was caused by the muscle fiber immaturity and inactivity.
Ann Neurol 1998 Dec
PMID:Muscle fiber immaturity and inactivity reduce myonecrosis in Duchenne muscular dystrophy. 985 44

The dynamics of perinatal mortality rates (PNMR) and causes of death in twin pregnancies over 13 years in the Northern Region of the National Health Service in England is described. All twin perinatal deaths occurring between 1982-1994 were identified from the Northern Region Perinatal Mortality Survey. The twinning rate increased from 9.9 per 1000 maternities in 1982 to 12.0 in 1994. There was a total of 10,734 twin pregnancies and of these 421 resulted in 530 perinatal deaths. The perinatal mortality rate in twins significantly decreased over time (1982-87, 55.4 per 1000; 1988-94, 44.4 per 1000; P = 0.01). The PNMR was significantly higher for twins from like-sexed than from unlike-sexed pairs (53.5 and 34.4 per 1000 respectively, P < 0.001). Despite no improvement in birthweight distribution in the twin population, birthweight-specific perinatal mortality rates for both like and unlike-sexed twins decreased for each birthweight category in 1988-94 compared with 1982-87. Twins with very low birthweight (< 1500 g) comprised 69%, and preterm twins (< 37 completed weeks of gestation) 74.9% of all twin perinatal deaths. The major immediate cause of early neonatal death was pulmonary immaturity (63%); antepartum anoxia caused 76.9% of antenatal deaths. Unexplained preterm labour and intrauterine death were the leading obstetric factors underlying death in twins. Despite a decrease over the 13 years, the perinatal mortality rate in twins in the Northern Region remains high. Continued monitoring of trends in twinning and mortality rates is needed to inform health care planning.
Twin Res 1998 Dec
PMID:Time trends in twin perinatal mortality in northern England, 1982-94. Northern Region Perinatal Mortality Survey Steering Group. 1010 Aug 10

Drug utilisation in term and preterm neonates (i.e. less than 28 days of age) has been investigated prospectively in 4 clinical studies during the past 10 years. 3880 neonates with a mean gestational age of 34.5 weeks (corresponding birthweight 2280g) were enrolled in these studies. An overview indicates a high prevalence of antibiotic treatment throughout the studies, ranging from 69% to virtually 100%. The highest prevalence was observed in studies enrolling only preterm neonates (gestational age less than 30 weeks) with need for mechanical ventilation. A further high prevalence of parenteral nutrition (84 to 100%), transfusion of blood products (91 to 100%) and vitamin use (16 to 78%) was described. Higher degrees of immaturity and rates of complications were associated with an increased drug usage up to a mean of 17 different drugs in very preterm (i.e. less than or equal to 30 weeks gestation) neonates with severe respiratory disorders and related complications. The high prevalence of antibiotic usage may be explained by the fact that clinical symptoms of neonatal bacterial infections are usually variable, and laboratory tests initially are not highly specific. Respiratory disorders in neonates are often associated with or caused by infections. Nosocomial infections in neonatal intensive care units further prompt administration of antimicrobial agents. Six prospective controlled clinical trials during the past 10 years have investigated treatment with dexamethasone of bronchopulmonary dysplasia, a chronic lung disease secondary to mechanical ventilation of surfactant-deficient lungs in very preterm neonates.(ABSTRACT TRUNCATED AT 250 WORDS)
Pharmacoeconomics 1993 Dec
PMID:Drug utilisation in preterm and term neonates. 1014 10

Some of the major barriers to telemedicine adoption relate to the immaturity of the industry, the limited telecommunications infrastructure, the lack of appropriate dialogue between vendors and buyers about solutions required, and the lack of industry partnerships. Remuneration is only one barrier. There are, of course, other substantial organizational, financial and attitudinal barriers. However, there are many promising aspects of the telemedicine industry in Australia that could provide the foundation for future innovation and expansion.
Telemed Today 1998 Dec
PMID:Pacific Rim report: Australia. 1033 41

Kawasaki disease (KD), an acute febrile disease in children of unknown etiology, is characterized by a vasculitis that may result in coronary artery aneurysms (CAAs). In new patients with KD, a selective and prolonged T cell unresponsiveness to activation via the T cell antigen receptor CD3 was observed, whereas proliferation to other stimuli was intact. This "split T cell anergy" delineated KD from other pediatric infections and autoimmune diseases and correlated with CAA formation (P<.001). A transient immune dysfunction was also suggested by an incomplete responsiveness to measles-mumps-rubella (MMR) vaccination in patients with KD versus controls (P<.0001; odds ratio, 15.6; 95% confidence interval, 4.8-51.1), which was overcome by revaccination(s). The reduced responsiveness to MMR in patients with KD suggests a subtle and predetermining immune dysfunction. An inherent immaturity to clear certain antigens may be an important cause that precipitates KD and the immune dysregulation during acute disease.
J Infect Dis 1999 Dec
PMID:Kawasaki disease: a maturational defect in immune responsiveness. 1055 43

We examined the neuroprotective efficacy of a post-treatment with idazoxan (Idaz): an alpha2-adrenoceptor antagonist with activity at the I1- and I2-subtypes of the imidazoline receptor (I-receptor), in an experimental model of perinatal hypoxic-ischemic (HI) brain damage. Seventy-two, 7-day-old Wistar rats were subjected to permanent unilateral ligation of the common carotid artery and transient (2 hr) hypoxia (8% O(2)). The surviving animals were sub-divided into 3 groups: one "control" group received intraperitoneal (i.p.) injection of saline (Sigma; n = 21) and two "treated" groups received, 10 min post-HI, i.p. treatments with Idaz (I3: 3 mg/kg; n = 19) or (I8: 8 mg/kg; n = 20). Idaz effects were assessed by TTC-staining 72 hr post-HI for Sigma (n = 13), I3 (n = 11), and I8 (n = 12) groups and by MRI-examination 5 weeks post-HI for Sigma (n = 8), I3 (n = 8), and I8 (n = 6) groups. Total ratio of brain infarct areas were significantly (P < 0.01) different between Sigma and Idaz-treated rats: 20.9 +/- 4.0%, 35.6 +/- 5.9 % and 36.8 +/- 5.8% for Sigma, I3 and I8, respectively, when determined with TTC-staining and; 23.3 +/- 3.7%, 39.8 +/- 4.2%, and 43.2 +/- 10.1%, for Sigma, I3, and I8, respectively, when assessed by MRI. Our results suggest that Idaz, given as a post-HI treatment, does not exert neuroprotective effects but enhances the brain injury induced by focal neonatal cerebral HI. The deleterious mechanism may result from an overactivity of sympathetic tone and/or the immaturity of central I-receptors in newborn rats.
J Neurosci Res 1999 Dec 01
PMID:Idazoxan does not prevent but worsens focal hypoxic-ischemic brain damage in neonatal Wistar rats. 1056 97


<< Previous 1 2 3 4 5 6 7 8 9 10