Reference values of body composition obtained by dual energy X-ray absorptiometry in preterm and term neonates

We have recently reported the cDNA cloning of rat spermatidal protein TP2 and its expression in Escherichia coli using pTrc 99A as the expression vector. However, the expression level was very low. We have now improved the expression of TP2 over fivefold by (1) optimizing the codons for lysine, arginine, proline, leucine, glycine, valine, threonine, alanine, and tyrosine and (2) by engineering the vector-encoded 5' UTR. The expressed protein was in the soluble phase and could be purified to homogeneity by successive chromatography on Zinc-NTA-agarose affinity matrix and heparin agarose. Serendipitously, we have also observed a concomitant hyperinduction of vector encoded beta-lactamase gene along with TP2 in the E. coli BL21 (DE3) cells.     

Renal handling of carnitine in ill preterm and term neonates

BACKGROUND/AIMS: A prospective study was performed to evaluate the incidence of bile leak after T-tube removal, using 99mTc labelled BULIDA scintigraphy. PATIENTS AND METHODS: Thirty seven patients with choledocholithiasis underwent choledocholithotomy and T-tube drainage. T-tubes were removed on 9--26 postoperative day (mean 13.4 days). RESULTS: Six (16%) patients had scintigraphic evidence of bile leak; 4 patients had leak demonstrated in the early phase only. One patient each had partial persistent leak and complete bile leak. All patients were managed nonsurgically; conservative treatment: (4), percutaneous drainage (PCD) of intra-abdominal collection (1) and endoscopic sphincterotomy and PCD of intra-abdominal collection (1). There was no significant difference in the leak rate when T-tubes were removed at < 2 weeks versus later than 2 weeks (P=.97). CONCLUSIONS: T-tubes should be removed with extreme caution and treatment of symptomatic patients should be guided by clinical and scintigraphic findings.     

Serum levels of müllerian inhibiting substance in preterm and term male neonates

PURPOSE: Müllerian inhibiting substance, also called anti-müllerian hormone, is responsible in the embryo for the regression of the müllerian structures. During the second and third trimesters the physiological functions that müllerian inhibiting substance may have after the period of müllerian duct regression are poorly understood. We obtained information on müllerian inhibiting substance levels in the male newborn during this period of gestation. MATERIALS AND METHODS: Müllerian inhibiting substance was measured by an enzyme immunoassay in cord blood obtained at birth in 27 preterm (25 to 36 weeks of gestation) and 92 term (37 to 42 weeks) male neonates. RESULTS: Cord serum müllerian inhibiting substance concentrations were relatively high from 25 to 31 weeks (mean plus or minus standard deviation 86.4 +/- 36.1 ng./ml.) and then they decreased from 32 weeks to term (mean 24.2 +/- 14.0 ng./ml.). CONCLUSIONS: The decline early in the third trimester may be consistent with müllerian inhibiting substance having a function during the second but a diminished role in the third trimester.     

Cerebral blood volume maps with dynamic contrast-enhanced T1-weighted FLASH imaging: normal values and preliminary clinical results

PURPOSE: In this article we investigate the application of a method that uses the relaxation effect of bolus-like injected Gd-DTPA to quantify regional cerebral blood volume (rCBV). The aim of the study was to determine if the method provides correct rCBV values in healthy subjects as well as to obtain additional diagnostic information for patients with a glioma or stroke. METHOD: Twenty healthy subjects, 12 patients with brain infarctions, and 18 patients with gliomas were examined. A series of 64 sequential images of one slice was recorded during bolus transit with a FLASH sequence. The measured signal intensity-time curves were converted pixel-wise to concentration-time curves from which the rCBV images were calculated applying the indicator dilution method. RESULTS: An average value for gray and white matter of 4.4 +/- 1.6 vol% was obtained for the group of healthy subjects. The grading of the tumors could be classified according to the differences of their corresponding rCBV values. Fifty percent of the infarct patients had to be excluded from the analysis in the acute phase due to mispositioning of the slice and data degradation by gross motion artifact. Different rCBV values were found for areas that develop later into gliotic scars or cystic necrosis. CONCLUSION: The proposed method is easy to apply in clinical routine MR investigations and provides valuable information for noninvasive, preoperative assessment of tumor grading. It can also provide additional criteria for estimating the histological outcome and with it the degree of ischemia in stroke patients.     

Cardiac and behavioral responses to repeated tactile and auditory stimulation by preterm and term neonates.

Auditory stimuli (a buzzer and rattle) and a tactile stimulus (a plastic filament) were repeatedly presented to 18 term and 18 preterm infants. Both groups initially responded to all stimuli with increased limb movements and heart rate acceleration. However, only the term infants responded to stimulus repetition by decreasing both cardiac and behavioral responses. In addition, they differentially responded to the 3 stimuli and showed response recovery in both systems. Since a behavioral response decrement was observed without a cardiac response decrement in the preterm group, a 2nd experiment was conducted. Heart rate change during the sucking activity of Exp II revealed an integration between autonomic and motor responsivity of preterm infants comparable to that of term newborns. The lack of cardiac–behavioral response integration during Exp I is discussed in the context of state differences between preterm and term infants as well as potential immaturity or some insult experienced by the preterm infants. The stimulus discrimination and habituation demands of Exp I may have overtaxed the preterm infants' ability to maintain response integration. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Spontaneous otoacoustic emissions in preterm neonates: prevalence and gender effects

A number of lines of evidence indicate that the human cochlea is fully functional as a mature sound transducer by 6 months of age. However, information about the development of the active cochlear mechanisms and notably the development of outer hair cell (OHC) activity is yet incomplete. Recording and analysis of otoacoustic emissions (OAEs), probably generated by the OHCs of the organ of Corti, have led to a better understanding, in humans, of how sounds are analysed in the cochlea by means of active mechanisms. Evoked OAEs (EOAEs) and spontaneous OAEs (SOAEs), when they can be recorded in full-term and preterm neonates, show different characteristics from those in adults, suggesting that maturation of the peripheral auditory system is incomplete at birth. To learn more about this maturation, using the best-established facts concerning SOAEs in adults, such as their greater prevalence in females and also in right ears, SOAEs were studied in more detail in 81 preterm neonates, from 30 to 40 weeks of conceptional age, all presenting bilateral EOAEs according to objective criteria. The first finding of this study was that SOAEs existed and could be recorded as of 30 weeks of conceptional age in humans. Some SOAE characteristics in preterm neonates, such as prevalence, peak number and acoustic frequencies, showed similarity with full-term neonates. Comparison of other criteria between the two populations, such as greater SOAE prevalence in right ears and higher SOAE peak number in females, suggested that these developmental factors emerge around term in humans. Comparison of SOAE characteristics between male and female preterms suggested that male preterms were less advanced in peripheral auditory development than were female preterms.     

Sympathetic skin response--physiologic principles, normal values and clinical use

Sympathetic skin reflex (SSR) was evaluated in the lower extremities of 60 normal volunteers aged 17 to 72 (mean age 38 +/- 16 years, 28 females, 32 males). SSR was obtainable in all volunteers and most often consisted of a biphasic wave with initial negative deflection. Mean latency was 2.16 +/- 0.20 s. Mean variation in a second repetitive measurement was 0.21 +/- 0.14 s. The SSR was not age- or sex dependent. There was a weak positive correlation of the SSR with the height of the volunteers (r = 0.271; p = 0.037). SSR was investigated in 39 patients with polyneuropathy (age 59 +/- 18). SSR was pathological in 51% on one or both legs. There was no correlation of the SSR to the aetiology nor to the type of lesion (axonal versus demyelinating polyneuropathy) nor to clinical symptoms. The applicability of the SSR is reviewed from the literature regarding polyneuropathy, erectile dysfunction, central degenerative diseases, multiple sclerosis, sympathetic reflex dystrophies, spinal and peripheral nerve lesions. SSR is briefly compared to alternative methods. SSR appears to be a reasonable method to describe a small section of the autonomic nervous system (sympathetic sudomotor function) and to calculate group differences. There appears to be no close correlation to any of the autonomic disturbances in individual patients.     

Facial and ear dimensions in term Nigerian neonates

A study of selected facial and ear dimensions in 200 term and appropriate-for-gestational age neonates delivered at the University College Hospital, Ibadan, Nigeria, was carried out with the aim of describing their normal range of variation and providing reference values for clinical use. The features studied included inner canthal distance, outer canthal distance, palpebral fissure length, nasolabial distance, oral intercommissural length, total ear length and ear length above the eyeline. The inner canthal distance ranged from 1.6 to 2.5 cm with a mean of 2.1 (SD 0.2) cm while the outer canthal distance ranged from 5.2 to 7.2 cm with a mean of 6.1 (SD 0.4) cm. The oral intercommissural length ranged from 2.5 to 4.0 cm with a mean of 3.1 (0.3) cm and the total ear length ranged from 2.4 to 4.0 cm with a mean of 3.2 (SD 0.3) cm. Three per cent of the neonates had the whole ear located completely below the eye line. No significant sex differences in the mean values of any of the dimensions studied were found. The findings of the study are consistent with those of other workers who have documented shorter ears in the Negro neonate compared to his Caucasian counterpart. It is suggested that local values derived from well-defined populations be used as reference in the evaluation of the child with dysmorphic features in order to avoid errors of classification due to racial variations in the range of normal.     

Reference values for young normal Sprague-Dawley rats: weight gain, hematology and clinical chemistry

1. Arterial blood from 63 male (315-500 g) and 60 female (210-290 g) healthy Sprague-Dawley rats was analyzed for 16 hematological and 22 clinical chemistry parameters. 2. Nine of these parameters were associated with growth and developmental changes in males between 38-78 days and females 49 - 89 days of age. 3. Weight gain in both sexes followed patterns consistent with other studies using this strain, but interexperimental variation was as much as +/-22%. 4. Rectal temperatures of females averaged 37.28 degrees C, being statistically greater (P < 0.05) than the average male at 36.99 degrees C. 5. The data provide reference values for use in toxicological and other investigations.     

Lipid peroxidation in healthy fetuses, preterm and fullterm neonates

Thrombolytic therapy has been accepted in the treatment of acute myocardial infarction. Given historical recommendations that thrombolytic therapy is contraindicated in patients receiving CPR, its potential clinical benefit for facilitating conversion of rhythm in patients in refractory cardiac arrest has not been investigated. We present three case reports in which patients with confirmed acute myocardial infarction had a witnessed cardiac arrest in the ED. Standard Advanced Cardiac Life Support measures failed in all three cases. A bolus infusion of tissue plasminogen activator was administered during CPR in refractory ventricular fibrillation (two cases) and pulseless ventricular tachycardia (one case). Patients were given tissue plasminogen activator and had defibrillation, followed by a spontaneous return of circulation, with resuscitation and subsequent discharge. No postarrest sequelae were observed as a result of thrombolytic use during the resuscitative process. We conclude that bolus thrombolytic infusions during CPR may facilitate spontaneous return of circulation in select patients with confirmed acute myocardial infarction, witnessed cardiac arrest in the ED, and refractory ventricular fibrillation or tachycardia.     

Endocervical pathogens in women with preterm and term labour

The purpose of this study was to compare the endocervical microflora of women in preterm and term labour and to determine whether the presence of a specific microflora is significantly associated with preterm labor. A prospective study was performed in Lithuania among 212 women in preterm labour (latent phase, n = 110; active phase, n = 102) and among 62 healthy women in term labour. Microbiological assessment included cultures for aerobic bacteria, yeasts, and Trichomonas vaginalis and direct immunofluorescence reaction for Chlamydia trachomatis, Escherichia coli (odds ratio 8.16; 95% confidence interval 1.27-340.23) and Staphylococcus aureus (odds ratio 7.79; 95% confidence interval 1.21-325.40) were significantly more often isolated from women in preterm than from women in term labour. The prevalence of C. trachomatis was the same in the preterm and in the term labour group. The pregnancy outcome during the latent or active phase of preterm labour with or without C. trachomatis infection did not differ. It is concluded that E. coli and S. aureus are significantly more prevalent in endocervical cultures from Lithuanian women in preterm than from those in term labour.     

Platelet-activating factor levels in term and preterm human milk

Tolterodine, a new muscarinic receptor antagonist, is metabolized via two pathways: oxidation of the 5-methyl group and dealkylation of the nitrogen. In an attempt to identify the specific cytochrome P450 enzymes involved in the metabolic pathway, tolterodine was incubated with microsomes from 10 different human liver samples where various cytochrome P450 activities had been rank ordered. Strong correlation was found between the formation of the 5-hydroxymethyl metabolite of tolterodine (5-HM) and CYP2D6 activity (r2, 0.87), as well as between the formation of N-dealkylated tolterodine and CYP3A activity (r2, 0.97). When tolterodine was incubated with human liver microsomes in the presence of compounds known to interact with different P450 isoforms, quinidine was found to be the strongest inhibitor of the formation of 5-HM. Ketoconazole and troleandomycin were found to be the strongest inhibitors of the formation of N-dealkylated tolterodine. A weak inhibitory effect on the formation of N-dealkylated tolterodine was found with sulfaphenazole, whereas tranylcypromine did not inhibit the formation of this metabolite. Microsomes from cells overexpressing CYP2D6 formed 5-HM, whereas N-dealkylated tolterodine was formed by microsomes expressing CYP2C9, -2C19, and -3A4. The Km for formation of N-dealkylated tolterodine by CYP3A4 was similar to that obtained in human liver microsomes and higher for CYP2C9 and -2C19. We conclude from these studies that the formation of 5-HM is catalyzed by CYP2D6 and that the formation of N-dealkylated tolterodine is predominantly catalyzed by CYP3A isoenzymes in human liver microsomes.     

Ureaplasma urealyticum, erythromycin and respiratory morbidity in high-risk preterm neonates

BACKGROUND: Response rate (RR) has been used as a defining endpoint of new-agent phase II trials for non-small-cell lung cancer (NSCLC). However, tumor responses to chemotherapy do not always result in prolonged survival of patients with this disease. DESIGN: Single-agent phase II trials were identified by a MEDLINE search of the period from 1976 to 1995. Associations between RR, median survival time (MST) and characteristics of patients who entered the trial, including tumor extent, performance status and prior chemotherapy, were studied by using the logistic regression model. RESULTS: A total of 183 treatment arms in 176 trials (including 10 randomized phase II trials) were identified. The overall RR in the 6768 evaluable patients was 11%. Eleven drugs, cisplatin, epirubicin, ifosfamide, edatrexate, irinotecan, vinorelbine, docetaxel, paclitaxel, etoposide, vindesine, and 254-S, produced a RR of more than 20%. An MST of eight months or longer was obtained with 12 drugs, but there were cases in which no objective responses were produced by these drugs. MST was correlated with RR (r = 0.504, P < 0.0001), but ranged broadly at a given level of RR. Multiple linear regression analysis showed a significant correlation between RR and MST (regression coefficient = 0.60, P = 0.00003) after adjustment for other variables. CONCLUSIONS: RR was significantly correlated with MST in single-agent phase II trials for NSCLC, but there is room for further consideration of the endpoint of these trials.     

Longitudinal evaluation of salivary cortisol levels in full-term and preterm neonates

The aim of the present study was to test the practicability of sequential cortisol determinations in saliva of low birth weight neonates and to evaluate the impact of systemic and inhaled glucocorticoid therapy on saliva concentrations of cortisol in preterm neonates with bronchopulmonary dysplasia (BPD). Salivary cortisol levels were measured by RIA in saliva samples from 10 full-term and 10 preterm healthy neonates and from 20 preterm neonates with BPD during systemic [dexamethasone (DEX); n = 10] or topical steroid therapy [budesonide (BUD); n = 10]. Saliva samples of each individual were collected on 3 consecutive days at 06.00, 12. 00, 18.00 and 24.00 h. Cortisol levels in saliva ranged from 0.8 to 60.6 nmol/l (median 6.5 nmol/l) in full-term neonates, from 0.6 to 52.1 nmol/l (median 5.5 nmol/l) in preterm neonates, from 0.4 to 14. 0 nmol/l (median 1.0 nmol/l) in preterm neonates treated with DEX and from 0.4 to 15.2 nmol/l (median 2.5 nmol/l) in preterm neonates treated with BUD. Autocorrelation analysis revealed a distinct endogenous cortisol rhythm in 2 of the 10 healthy full-term neonates and in 3 of the 10 healthy preterm neonates with a wavelength of 12-30 h. Salivary cortisol levels in preterm neonates treated with DEX or BUD were significantly lower than those measured in healthy preterm neonates. These results demonstrate that the measurement of salivary cortisol levels is a reliable and practicable way of assessing adrenal function in full-term and preterm neonates. This study also shows for the first time that some neonates display an endogenous cortisol rhythm which is not coupled to the exogenous day/night cycle. Furthermore, systemic and nebulized glucocorticoids suppress adrenal function in low-birth-weight neonates. After treatment these children should be closely monitored for potential adrenal insufficiency.     

Complement and contact activation in term neonates after fetal acidosis

AIMS: To evaluate complement and contact activation after fetal acidosis. METHODS: Fifteen term neonates with hypoxic-ischaemic encephalopathy after umbilical arterial pH < 7.10 were compared with 15 healthy neonates with umbilical arterial pH > 7.20. Determinations of the complement function and C1-inhibitor activity were performed as kinetic tests 22-28 hours after birth. C1q, C1-inhibitor, and factor B concentrations were determined by radial immunodiffusion and those of C3a, C5a, and factor XIIa by enzyme immunoabsorbent assay. RESULTS: Median complement function (46 vs 73%), C1q (4.3 vs 9.1 mg/dl), and factor B (5.2 vs 7.7 mg/dl) decreased after fetal acidosis. The activated split products C3a (260 vs 185 micrograms/l), C5a (5.0 vs 0.6 micrograms/l), and factor XIIa (3.2 vs 1.3 micrograms/l) increased in the neonates after fetal acidosis. No differences were found in the concentration and activity of C1-inhibitor. CONCLUSIONS: Complement and contact activation occurred in the newborns with hypoxic-ischaemic encephalopathy. Activation of these systems generates mediators which can trigger inflammation and tissue injury.     

Electrophysiologic changes in preterm neonates: auditory brain stem response and distortion product otoacoustic emissions

The purposes of this investigation were to determine 1) if auditory peripheral maturity is present in the newborn; 2) if not, at what age maturational changes occur in the peripheral auditory system from preterm to full-term; and 3) how results of tests used to identify auditory dysfunction in neonates, such as distortion product otoacoustic emissions (DPEs) and auditory brain stem responses (ABRs), change during this period. Longitudinal DPE amplitude and ABR wave I latency measurements were obtained from a single ear of 18 preterm neonates. The DPEs were evoked at f2s of 2, 3, 4, and 5 kHz. The longitudinal data revealed that in general, DPE amplitude increased and ABR wave I latency decreased as a function of postconceptional age. These findings suggest that 1) the peripheral auditory system has not reached maturity in the preterm neonate; 2) maturational changes continue from preterm to full-term; and 3) these changes are reflected in ABR and DPE measurements.     

Capillary refilling time in newborn babies: normal values

AIM: To assess the normal values of capillary refilling time (CRT) in healthy newborn babies; to assess the effect of different nursery containers (incubator, radiant warmer, crib), phototherapy, birthweight, gestational age, size for gestational age and sex on CRT; to compare CRT at different body sites as well as to assess the variation between observers. METHODS: Healthy neonates (n = 469) of different gestational ages and different sizes for gestational age, were studied 1 to 7 days after birth. CRT was measured in four of the most suitable sites-namely, midpoints of the sternum and the forehead, the palm of the hand and the plantar surface of the heel (defined as chest, head, palm and heel, respectively). The applied pressing time was 5 seconds. CRT was measured with a manual stopwatch. RESULTS: Only the chest and the head distribution curves followed the Gaussian curve. The mean values and standard deviation of CRT in all tested nursery containers, including phototherapy for the chest, ranged from 1.82 (0.34) seconds to 2.01 (0.423) seconds, and for the head from 1.59 (0.36) seconds to 1.83 (0.31) seconds. The mean value of chest CRT was always longer than the head CRT for all parameters. Significant differences were found between different nursery containers, receivers, and non-receivers of phototherapy and between observers. No difference was found between sex, birthweight, gestational age and size for gestational age. CONCLUSIONS: The upper limit of normal for neonatal CRT was 3 seconds. Nursery containers, phototherapy, and observers produced significantly different results, but the differences were not clinically important. CRT values of the midpoints of the sternum and the forehead are the most consistent.     

Contact system in healthy term newborns: reference values in cord blood

Humoral hypercalcemia refers to the elevated blood calcium levels caused by neoplasms which release a bone resorptive substance into the circulation. Previously reported infants with malignant and benign solid tumors causing humoral hypercalcemia have presented with large abdominal masses. The case we describe, a hypercalcemic infant due to an occult parathyroid hormone-related protein-containing metanephric adenoma of the kidney, shows that radionuclide bone scanning can be a useful test to identify humoral hypercalcemia. Humoral hypercalcemia stemming from a soft tissue neoplasm should be ruled out, even in the absence of clinical signs of a tumor, if bone scans show generalized uptake in the absence of hypervitaminosis D or radiological signs of bone lesions, and serum parathyroid hormone is low.     

On carnitine requirements in full term and low birth weight neonates

The concentration of total carnitine in the blood serum of 15 newborns between days 5-21 of life was determined. The concentration of carnitine in low-birth-weight newborns is decreased in comparison with normal weight newborns; this deficiency may increase as a consequence of lack of carnitine provided with food or concomitant infection. The authors suggest that supplementation with carnitine be provided to this group of patients so as to prevent possible metabolic and clinical consequences.