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1.
OBJECTIVE: To evaluate the clinical application of a new classification system of fetal lung anomalies. METHODS: Forty fetal diagnoses of lung lesions were analyzed according to our proposed classification system in which each lung component is considered using two-dimensional ultrasound and color and power Doppler technology. Medical files, natural history and neonatal follow-up were recorded. RESULTS: Type I dysplasia: Four cases of agenesis of the lung were diagnosed, three with right lung agenesis and one with left lung agenesis. Three of the four patients elected to undergo termination of pregnancy (TOP). The surviving fetus was diagnosed with scimitar syndrome and postnatal embolization of the aberrant vessel was performed. Type II dysplasia: One case of normal lung with abnormal systemic feeding artery was diagnosed with normal neonatal outcome. Type III dysplasia: Abnormal lung with abnormal vascularity was found in 14 cases, presenting in most cases as echogenic lung masses. Seven were supradiaphragmatic, six subdiaphragmatic and one case was of undetermined position. All 14 fetuses showed an aberrant systemic artery emerging from the aorta. Abnormal venous drainage could be identified in only five (36%) of the fetuses: three had prominent azygos vein, one showed drainage to the inferior vena cava and one had multiple intrapulmonary veins forming a huge arteriovenous (A-V) shunt. Two cases in this group underwent TOP, the case with A-V shunt following development of hydrops, and one on maternal request. The remaining 12 fetuses (86%) survived and were alive and well at the time of writing; only one of them needed immediate postnatal embolization of the bilateral aberrant feeding arteries. Type IV dysplasia: Abnormal lung with no vascular abnormality was diagnosed in 20 fetuses. In this group there was one case of intrauterine fetal death, two patients underwent TOP, one complicated with hydrops and one on maternal request. The survival rate in this group was 85%. Only two cases needed immediate surgical repair. Type V miscellaneous dysplasia: One fetus demonstrated echogenic lung with split notochord syndrome and survived. CONCLUSIONS: Congenital bronchopulmonary and related vascular anomalies can be categorized using the new classification system. This new approach enabled prenatal evaluation of each lung component and facilitated cogent management of the fetus with congenital lung dysplasia.  相似文献   
2.
The binding of plasminogen to Mycoplasma fermentans was studied by an immunoblot analysis and by a binding assay using iodine-labeled plasminogen. The binding of 125I-labeled plasminogen was inhibited by unlabeled plasminogen, lysine, and lysine analog epsilon-aminocaproic acid. Partial inhibition was obtained by a plasminogen fragment containing kringles 1 to 3 whereas almost no inhibition was observed with a fragment containing kringle 4. Scatchard analysis revealed a dual-phase interaction, one with a dissociation constant (kd) of 0.5 microM and the second with a kd of 7.5 microM. The estimated numbers of plasminogen molecules bound were calculated to be 110 and 790 per cell, respectively. Autoradiograms of ligand blots containing M. fermentans membrane proteins incubated with 125I-labeled plasminogen identified two plasminogen-binding proteins of about 32 and 55 kDa. The binding of plasminogen to M. fermentans enhances the activation of plasminogen to plasmin by the urokinase-type plasminogen activator (uPA), as monitored by measuring the breakdown of chromogenic substrate S-2251. Enhancement was more pronounced with the low-molecular-weight and the single-chain uPA variants, known to have low plasminogen activator activities. The binding of plasminogen also promotes the invasion of HeLa cells by M. fermentans. Invasion was more pronounced in the presence of uPA, suggesting that the ability of the organism to invade host cells stems not only from its potential to bind plasminogen but also from the activation of plasminogen to plasmin.  相似文献   
3.
A purified preparation of membranes was obtained by using a unique method of treating Mycoplasma pneumoniae with the ATPase inhibitor, diethylstilbestrol. This method was shown to yield highly purified membranes with little or no cytoplasmic contamination. These membranes were used to immunize mice for subsequent productions of monoclonal antibodies (MAbs). Hybridoma culture supernatants were screened by enzyme-linked immunosorbent assay with whole-cell M. pneumoniae and lipid extract antigens. Four stable MAbs were obtained and characterized. MAb CP3-46F5 reacted with a protein of a molecular weight of approximately 52,000 as determined by Western blot (immunoblot). MAbs CP3-50C2, CP3-53C5, and CP3-53C8 did not react with any antigens on Western blots but did bind to at least 10 distinct glycolipid bands as determined by orcinol staining on thin-layer chromatograms of M. pneumoniae lipid extracts. The MAbs did not react with similarly prepared lipid extracts from Mycoplasma genitalium, Mycoplasma neurolyticum, and Mycoplasma gallisepticum. These MAbs did not inhibit M. pneumoniae metabolism or attachment to WiDr cell cultures. The anti-glycolipid MAbs recognize determinants specific to M. pneumoniae, unlike polyclonal hyperimmune sera against M. pneumoniae, which cross-react with lipid extracts of M. genitalium.  相似文献   
4.
5.
Low melatonin production in infants with a life-threatening event   总被引:3,自引:0,他引:3  
This study compares the urinary excretion of the main melatonin metabolite, 6-sulfatoxymelatonin (6SMT), in infants who have and have not experienced a life-threatening event (ALTE). 6SMT was assessed in the following groups of infants: 15 infants with ALTE for whom home monitoring had been recommended, 15 infants who had had an abrupt cyanotic apneic event but did not require mouth-to-mouth resuscitation, 15 siblings of those who had died from sudden infant death syndrome (SIDS), and 35 age-matched healthy comparison infants. All 80 infants were between 48 and 58 weeks of postconceptional age. On a double-blind basis, the total amount of 6SMT excreted over 24 hours and the diurnal rhythm in the rate of 6SMT excretion were assessed using urine samples taken from disposable diapers (nappies). The mean daily excretion of 6SMT was significantly lower in the ALTE (1,588 ng/24 hour) than in the comparison infants (3,961 ng/24 hour). No such difference was found between the infants with a cyanotic apneic event (3,268 ng/24 hour) and the SIDS siblings (2,962 ng/24 hour). The diurnal 6SMT rhythms in the ALTE infants were characterized by lower 24-hour mean and amplitude values, whereas the time of peak and nadir excretion rates (07:15 to 08:45 hours and 14:45 to 16:15 hours respectively) was similar in all four infant groups. Follow-up of the ALTE infants, performed 6 to 8 weeks later (59 to 66 weeks of postconceptional age), revealed that 6SMT excretion increased in all of them, suggesting a delayed ontogeny rather than permanent deficiency of melatonin production in ALTE.  相似文献   
6.
Mycoplasma hyorhinis has been implicated in a variety of swine diseases. However, little is known about the hemolytic capabilities of Mycoplasma species in general or M. hyorhinis in particular. In this study, we show that M. hyorhinis possesses beta-hemolytic activity which may be involved in the invasion process. M. hyorhinis also possesses antagonistic cooperativity (reverse CAMP phenomenon) with Staphylococcus aureus beta-hemolysis, resulting in the protection of erythrocytes from the beta-hemolytic activity of S. aureus (reverse CAMP). The reversed CAMP phenomenon has been attributed to phospholipase D (PLD) activity. In silico analysis of the M. hyorhinis genome revealed the absence of the pld gene but the presence of the cls gene encoding cardiolipin synthetase, which contains two PLD active domains. The transformation of Mycoplasma gallisepticum that has neither the cls gene nor the reverse CAMP phenomenon with the cls gene from M. hyorhinis resulted in the reverse CAMP phenomenon, suggesting for the first time that reverse CAMP can be induced by cardiolipin synthetase.  相似文献   
7.
Summary Pefloxacin was applied to a newborn suffering from ventriculitis caused byKlebsiella pneumoniae after failure of routine antibiotics. Treatment was successful. Blood and CSF levels were high, thus documenting good CSF penetration. In addition to this case report, a review of the literature regarding seven neonates with CNS infection treated with fluoroquinolones and from whom CSF levels were obtained, is presented. In conclusion, due to their excellent activity against gram-negative microorganisms, fluoroquinolones may be considered in the treatment of neonatal CNS infections if the pathogen is resistant to routinely used antibiotics. Only limited experience is available with fluoroquinolones in pediatric patients given their potential for cartilage toxicity in young animals.
Ventrikulitis durchKlebsiella pneumoniae bei einem Neugeborenen. Erfolgreiche Behandlung mit Pefloxacin
Zusammenfassung Nach Versagen von Routineantibiotika wurde Pefloxacin eingesetzt, um eine durchKlebsiella pneumoniae verursachte Ventrikulitis bei einem Neugeborenen zu behandeln. Die Therapie war erfolgreich. Im Blut und im Liquor cerebrospinalis fanden sich hohe Spiegel von Pefloxacin. Die hohe Penetrationsrate von Pefloxacin in den Liquor ist damit dokumentiert. In einer Literaturübersicht werden sieben weitere Fälle von ZNS-Infektionen bei Neugeborenen dargestellt, die unter Bestimmung der Liquorspiegel mit Fluorochinolonen behandelt wurden. Fluorochinolone kommen wegen ihrer hohen Aktivität gegen gramnegative Bakterien für die Behandlung einer gegen herkömmliche Antibiotika resistenten gramnegativen ZNS-Infektion bei Neugeborenen in Frage. Die Erfahrungen mit Fluorochinolonen sind bei pädiatrischen Patienten jedoch wegen der Möglichkeit einer bei jungen Tieren beobachteten Knorpelschädigung begrenzt.
  相似文献   
8.
The present study examined well‐being and personal growth in mothers (n = 414) 1 year after childbirth. We examined the contribution of the event characteristics (birth of singletons or twins, full‐ or pre‐term babies, first or non‐first child, spontaneous pregnancy or fertility treatments and infant temperament), internal resources (attachment anxiety and avoidance) and external resources (marital quality and maternal grandmother's support). Regressions indicated that having a first child, child's easier temperament, lower attachment anxiety and avoidance, grandmother's emotional support and some aspects of the spousal relationships contributed to well‐being. Personal growth was found to be related to the birth of a pre‐term baby or babies, positively associated with maternal grandmother's support, and the marital quality of parenthood, and negatively with mothers' education. Beyond the findings that well‐being and personal growth are related to the availability of certain resources, the current study demonstrates that the two outcomes are separate phenomena that reveal different patterns of associations with other variables. Several explanations for the findings are proposed, and practical implications are discussed. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
9.
While it is known that mast cells arise from pluripotential hematopoietic cells and express their mature phenotypes in tissues, the sequence of events in maturation is incompletely understood. To study early mast cells, we sorted cells from interleukin-3 (IL-3)-dependent mouse bone marrow cultures on the basis of Fc epsilon RI and examined their morphology, histamine content, and growth characteristics. Flow cytometric analysis and sort showed that the Fc epsilon RI-bearing (Fc epsilon RI+) cells increased from 0% on day 0 to 90% by day 21 and that the total number of Fc epsilon RI+ cells increased from 0 at the start of culture to 3.75 x 10(5) cells by day 21 from an initial population of 1 x 10(5) cells. The dissociation rate of 125I-labeled IgE from early cultured cells resembled the dissociation rate of mouse IgE from mature murine mast cells. Mean fluorescence intensity increased over time, reflecting an increase in IgE receptor density. Fc epsilon RI+ cells were also positive for Fc gamma RII/III. Morphologic studies showed gradual acquisition of metachromatic granules in the Fc epsilon RI+ cells, which was paralleled by an increase in histamine content. Sorted Fc epsilon RI+ cells, when placed in liquid suspension culture, gave rise to pure mast cell populations. Fc epsilon RI+ cells sorted at day 3 and cultured in agarose with IL-3 gave rise to 4,800 small and 150 medium-size mast cell colony-forming units per 10(6) cells, while Fc epsilon RI- cells gave rise to 23 medium-size and 49 large mast cell colony-forming units per 10(6) cells. Fc epsilon RI+ cells grown in granulocyte-macrophage colony-stimulating factor (CSF) or macrophage-CSF did not give rise to colony-forming units. These results show that Fc epsilon RI+ cells have proliferative potential, but that there also is a population of mast cell progenitor cells that have not yet expressed Fc epsilon RI, and such individual progenitor cells have greater potential for proliferation than cells that express Fc epsilon RI.  相似文献   
10.
Aim: To evaluate the performance of exchange transfusion in very low birth weight (VLBW) infants with excessively high serum bilirubin levels. Methods: A population‐based observational study using data collected by the Israel National VLBW Infant Database. The study sample comprised 13 499 infants. Two definitions of excessively high‐peak bilirubin levels that might be considered as threshold levels for performance of exchange transfusion were used. First, a bilirubin level of ≥15 mg/dL for all infants (PSB‐15), and second, incremental bilirubin levels ranging from 12 to 17 mg/dL according to gestational age (PSB‐GA). Results: Four hundreds sixty‐eight (3.5%) and 1035 infants (7.7%) infants in the PSB‐15 and in the PSB‐GA groups respectively had peak serum bilirubin levels above thresholds for exchange transfusion. Exchange transfusions were performed in 66 (14.1%) of these infants in the PSB‐15 group and 91 (8.8%) in the PSB‐GA group. Using logistic regression analysis, peak serum bilirubin was found as an independent factor for performing exchange transfusion. Conclusion: Exchange transfusion was performed in only 9–14% of VLBW infants with excessively high bilirubin levels. We speculate that this may be a result of an absence of definitive guidelines or the possible belief that the risks of exchange transfusion outweigh the potential risk of bilirubin‐induced neurological injuries.  相似文献   
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