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M C Yoder

Publications and source records attributed to M C Yoder.

At least 55 records · Page 3Linked to original sources
PubMed1989

Delayed presentation of a right-sided diaphragmatic hernia and group B streptococcal sepsis. Two case reports and a review of the literature.

Group B streptococcal sepsis was associated with delayed presentation of an unsuspected right-sided diaphragmatic hernia in two neonates. These unusual clinical observations and a review of 24 similar cases from the literature form the basis of this report. Infants present with respiratory distress during the first few hours of life and have group B streptococcal sepsis confirmed by results of blood cultures. The right side of the diaphragm appears normal on the initial chest roentgenogram in the majority of cases. After initial improvement with antibiotic therapy and ventilatory support, sudden deterioration of respiratory status may occur. Subsequent chest roentgenograms often demonstrate herniated viscera in half of the cases, while ultrasound examination, isotopic liver scan, and peritoneography are useful in achieving a diagnosis in the other cases. If recognized, survival is 100% following hernia repair. Persistent respiratory symptoms in a neonate who is recovering from group B streptococcal sepsis should prompt a careful evaluation of the right side of the diaphragm for the presence of an unsuspected posterolateral hernia.

Hernia, Diaphragmatic↗
PubMed1989

Fibronectin turnover in the premature neonate measured with [15N]glycine.

Fibronectin is a large-molecular-weight glycoprotein present on most cell surfaces and in plasma. Plasma fibronectin concentrations in neonates are lower than those in adults and a direct relationship exists between plasma concentration and gestational age. We determined the half-life and fractional synthetic rate (FSR) of plasma fibronectin in the premature infant. Infants and adults received a loading dose of [15N]glycine followed by a constant infusion [15N]glycine incorporation into plasma fibronectin and urine hippurate was determined by gas chromatography-mass spectrometry. The plasma fibronectin FSR in the preterm neonates was 15.5 +/- 9.9%/d(means +/- SD) and the half-life was 5.55 +/- 2.25 d. Birth weight correlated inversely with plasma fibronectin half-life. In the adults the plasma fibronectin FSR ranged from 20 to 87%/d and half-life ranged between 0.79 and 3.47 d. These data suggest that decreased plasma fibronectin levels in preterm infants are due to reduced FSRs rather than to greater turnover of a relatively small plasma pool.

Adult↗
PubMed1988

Culture medium oxygen tension affects fibronectin production in human adult and cord blood macrophages.

Varying culture medium oxygen tension from one-half to twice the normal concentration did not alter adult or cord blood monocyte-derived macrophage secretion of lysozyme or total protein. Lowering oxygen tension did result in significant increases in fibronectin concentration in both adult and cord blood macrophage culture supernatants. Dexamethasone (10(-7) M) completely blocked adult macrophage but had no effect on cord blood macrophage fibronectin release in response to lowering oxygen tension. These results indicate that human macrophages selectively regulate fibronectin production in response to changes in oxygen tension in vitro.

Adult↗
PubMed1988

Vitamin E decreases superoxide anion production by polymorphonuclear leukocytes.

Pharmacologic serum levels of vitamin E administered to low birth weight infants predispose them to infectious complications. We studied in vitro the effect of vitamin E, its vehicle and buffer (Krebs Ringers phosphate glucose) on the ability of human polymorphonuclear leukocytes (PMN) to produce superoxide anion, an oxygen radical important for bacterial killing. We found that superoxide anion production after a 5-min exposure to phorbol myristate acetate was significantly decreased in vitamin E-treated PMN (76 +/- 15 nM/10(7) PMN) compared to vehicle-treated PMN (289 +/- 109 nM/10(7) PMN). We also found that significantly decreased superoxide anion production was associated with 5.0 and 10.0 mg/dl but not with 3.5 mg/dl vitamin E. Our results support the hypothesis that pharmacologic concentrations of vitamin E depress PMN oxidative activity.

Adult↗
PubMed1988

Neonatal sepsis.

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Bacterial Infections↗
PubMed1987

Enhanced endotoxin effects in plasma fibronectin-deficient rats.

Immunoreactive plasma fibronectin depletion has been associated with the presence of collagen-fibronectin complexes in patients after trauma and in animal models of traumatic and burn injuries. However, the role of plasma fibronectin in the development of sepsis after traumatic and burn injuries in patients is unknown. Treatment of patients and animals with purified human plasma fibronectin ameliorates some of the clinical and metabolic effects of systemic endotoxemia. We report that the induction of immunoreactive plasma fibronectin deficiency by gelatin infusion is associated with enhanced effects of intraperitoneal Escherichia coli endotoxin injection. We have observed a significant increase in the concentrations of ammonia in plasma of treated rats compared with those in control rats administered the same dose of endotoxin.

Ammonia↗
PubMed1987

Staphylococcal adherence to polyvinyl chloride and heparin-bonded polyurethane catheters is species dependent and enhanced by fibronectin.

Intravenous hyperalimentation has improved the survival of premature infants. However, long-term placement of intravenous catheters may result in the development of catheter-related sepsis. Fibronectin in plasma contains binding sites for staphylococcal species as well as marked affinity for inert plastics and therefore may provide a substrate for bacterial adherence to indwelling catheters. We determined the adherence of labeled [( 3H]leucine) coagulase-positive (CPS) and coagulase-negative (CNS) staphylococci to untreated and fibronectin-coated polyvinyl chloride (PVC) and heparin-bonded polyurethane (HBP) catheter segments and quantitated the binding of 14C-labeled, purified fibronectin to these catheters. PVC catheter segments bound significantly more CNS than CPS (P less than 0.05), while HBP catheters bound more CPS than CNS (P less than 0.05). Fibronectin significantly increased the adherence of CPS to PVC catheters (P less than 0.05) and CNS to HBP catheters (P less than 0.05). PVC catheters bound more fibronectin (P less than 0.0001) than did HBP catheters. Catheter composition may influence the spectrum of nosocomial pathogens to which infants are susceptible through different bacterial adherences and interactions with adhesive proteins.

Bacterial Adhesion↗
PubMed1986

Tracheal lavage and plasma fibronectin: relationship to respiratory distress syndrome and development of bronchopulmonary dysplasia.

Plasma for fibronectin determinations was obtained from 39 neonates with uncomplicated respiratory distress syndrome (RDS) and from 15 infants with RDS who developed bronchopulmonary dysplasia (BPD). Tracheal lavage fibronectin and albumin concentrations were measured in 15 infants with RDS and 15 with BPD. Control plasma fibronectin values were obtained from 20 healthy preterm infants on days 1, 2, 3, 14, and 30 of life. Control tracheal lavage fibronectin and albumin concentrations were measured in 17 neonates of various gestational ages who required tracheal intubation for nonpulmonary indications. Mean plasma fibronectin concentrations from patients with RDS was 121 +/- 11 micrograms/ml on days 1, 2, and 3, versus control level of 163 +/- 12 micrograms/ml (P less than 0.01). Mean tracheal lavage fibronectin/albumin ratio was 3.8 +/- 0.6 ng per microgram of albumin on days 1 to 5 for infants with RDS, versus control level of 5.6 +/- 3.6 (P = NS). Tracheal lavage fibronectin/albumin ratio from patients with BPD was elevated at 16.3 +/- 5.0 ng fibronectin per microgram of albumin on days 14 to 21, and 23.6 +/- 7.4 on day 30 (P less than 0.05 versus control and and versus RDS days 1 to 10). Low plasma fibronectin concentrations early in RDS may contribute to the development of pulmonary capillary leak. High tracheal lavage fibronectin levels may foster the development of pulmonary fibrosis in patients with BPD.

Albumins↗
PubMed1986

Immunotherapy of neonatal septicemia.

This chapter has reviewed the deficiencies in immune defense that place the neonate, particularly the premature infant, at increased risk of invasive bacterial disease. We also have reviewed the literature on the rationale for exchange transfusion, granulocyte transfusion, intravenous immunoglobulin, and fibronectin administration as immunotherapeutic agents in infected infants. There have been no randomized controlled trials of exchange transfusion, immunoglobulin, or fibronectin administration in human infants with infection. Granulocyte transfusion in the infected newborn infant has been studied in a controlled fashion, but the results of clinical trials are conflicting. Thus, all of these interventions appear to need further evaluation. We therefore recommend that in the septic newborn infant with neutropenia and an I/T ratio greater than or equal to 0.8, who fails to demonstrate a favorable response to conventional antibacterial chemotherapy and cardiopulmonary support, the administration of approximately 1 X 10(9) irradiated granulocytes per kg may be beneficial. In the absence of equipment to isolate the granulocytes, a double-volume exchange transfusion with fresh heparinized whole blood will provide a similar quantity of functional phagocytes.

Antibody Formation↗
PubMed1986

Endotoxin-induced changes in nitrogen metabolism.

Intraperitoneal administration of a sublethal dose of E. coli endotoxin to fasted rats produced within 12 hrs a rise in plasma ammonia, urea, glutamine, glutamate and aspartate as compared to controls. At this time, hepatic ureagenesis also increased as did the levels of glutamate, glutamine, aspartate, alanine and asparagine. However, liver glucose and ketone levels were unchanged. Hepatic [ATP]/[ADP] ratios declined in endotoxin-treated animals and there was an oxidation of mitochondrial pyridine nucleotides and a reduction of cytosolic pyridine nucleotides. The results suggest that impairment of nitrogen metabolism is an early effect of endotoxemia.

Amino Acids↗
PubMed1985

Metabolic and mitochondrial morphological changes that mimic Reye syndrome after endotoxin administration to rats.

The administration of sublethal doses of Escherichia coli O111:B4 endotoxin to starved rats results in significant increases in plasma ammonia, free fatty acids, and serum lactate compared with starved controls. These metabolic alterations are associated with Reye syndrome-like histological findings of hepatic microvesicular fatty accumulation and hepatic ultrastructural evidence of mitochondrial pleomorphism with matrix disruption. This sublethal endotoxin model may help elucidate the relationship between the hepatic mitochondrial injury, characteristic metabolic impairment, and encephalopathy seen in patients with Reye syndrome.

Alanine Transaminase↗
PubMed1984

Decreased fibronectin biosynthesis by human cord blood mononuclear phagocytes in vitro.

Cultured cord blood monocytes synthesize significantly less fibronectin than cultured monocyte-macrophages from adult peripheral blood. Biosynthesis of the second component of complement in vitro is similar for both cell systems. The monocyte-macrophages from neonates and adults have similar functional and morphologic properties in long-term cultures. The decreased monocyte-macrophage biosynthesis of fibronectin observed in vitro may be in part related to the reduced plasma fibronectin concentrations and reticuloendothelial system hypofunction which occur in newborn infants.

Adult↗
PubMed1983

Decreased plasma fibronectin in neonatal sepsis.

Fibronectin is a large opsonic glycoprotein which promotes reticuloendothelial system clearance of bacteria, immune complexes, collagenous debris, and damaged platelets. The concentration of plasma fibronectin is decreased in the newborn infant; however, the role of fibronectin in the onset and course of neonatal sepsis is unknown. Serial plasma fibronectin levels were determined in 19 neonates with documented bacterial sepsis. Plasma fibronectin concentrations decreased significantly (P less than .001) in all study infants concurrent with the development of septicemia. Recovery of plasma fibronectin to normal levels occurred by day 5 in premature neonates and by days 7 to 10 in term neonates. Fibronectin deficiency and resultant reticuloendothelial system impairment may decrease the ability of newborn infants to resist or clear bacterial infections. An acute reduction in the concentration of plasma fibronectin may be a valuable marker for neonatal sepsis.

Bacterial Infections↗
PubMedDate not supplied

Comparison of serum fibronectin, prealbumin, and albumin concentrations during nutritional repletion in protein-calorie malnourished infants.

Anthropometric measurements and serum fibronectin, prealbumin, and albumin concentrations were determined on admission and during the hospitalization of 20 noninfected infants with protein-calorie malnutrition. Serum fibronectin concentrations were significantly decreased on admission but increased to greater than normal serum values in 2 weeks. During this same interval, serum prealbumin values rose from significantly decreased to normal levels. Serum albumin concentrations and anthropometric measurements were not significantly elevated above admission levels until the fourth week of nutritional support. Serum fibronectin and prealbumin concentrations may serve as indices of the short-term efficacy of nutritional support in noninfected infants with protein-calorie malnutrition.

Anthropometry↗
PubMedDate not supplied

Association of maternal lithium exposure and premature delivery.

Lithium is widely used and the treatment of choice for patients with manic-depressive illness. For pregnant patients with manic-depressive illness, however, the use of lithium during the first trimester of pregnancy may present an increased risk for fetal maldevelopment. We have recently cared for several large-for-gestational-age, prematurely born infants whose mothers were treated with lithium throughout pregnancy. To determine whether maternal lithium use during pregnancy may predispose to the onset of premature labor and fetal macrosomia, we reviewed records from the International Register of Lithium Babies and from a cohort of manic-depressive pregnant women. More than one third (36%) of infants reported to the International Register were born prematurely, and 37% of the premature infants were large for gestational age; 15% of the term infants were born large for gestational age. In the cohort group, manic-depressive mothers who received lithium during pregnancy had a 2.5-fold higher incidence of premature births than manic-depressive pregnant patients who did not receive lithium treatment. The incidence of large-for-gestational-age births in lithium-treated women in the cohort was not different from that of the general population or from manic-depressive women not treated with lithium. In summary, an association between maternal lithium therapy and premature delivery is reported. We recommend that women receiving lithium therapy during pregnancy be closely monitored for the onset of premature labor.

Adult↗