Severe refractory warm autoimmune haemolytic anaemia after the SARS-CoV-2 Pfizer-BioNTech vaccine (BNT162b2 mRNA) managed with emergency splenectomy and complement inhibition with eculizumab

A male in his teens with a history of liver transplant for biliary atresia (aged 2 years) and autoimmune haemolytic anaemia (AIHA, aged 6 years) presented with jaundice, dark urine, fatigue and chest discomfort that began 48 hours after the first dose of SARS-CoV-2 Pfizer-BioNTech vaccine (BNT162b2 mRNA). Investigations revealed a warm AIHA picture. Over 4 weeks the patient developed life-threatening anaemia culminating in haemoglobin of 35 g/L (after transfusion), lactate dehydrogenase of 1293 units/L and bilirubin of 228 µmol/L, refractory to standard treatment with corticosteroids and rituximab. An emergency splenectomy was performed that slowed haemolysis but did not completely ameliorate it. Eculizumab, a terminal complement pathway inhibitor, was initiated to arrest intravascular haemolysis and showed a favourable response. AIHA is rare but described after the SARS-CoV-2 Pfizer-BioNTech vaccine. This case highlights the rare complication of AIHA, the use of emergency splenectomy for disease control, and the use of eculizumab.

Ultrafast Brain MRI Can Be Used for Indications beyond Shunted Hydrocephalus in Pediatric Patients

BACKGROUND AND PURPOSE

Evaluation of shunted hydrocephalus is the most common indication for ultrafast brain MRI. Radiation-/sedation-free imaging capabilities make this protocol more desirable over CT and standard brain MRI. We hypothesized that ultrafast brain MRI can be used for selected indications beyond shunted hydrocephalus without adverse outcomes.

MATERIALS AND METHODS

Ultrafast brain MRI was performed with axial, sagittal, and coronal HASTE. The radiology information system was used to identify pediatric patients (0-18 years of age) who underwent ultrafast brain MRI between March 2014 and May 2016. A retrospective chart review was completed to identify indications other than shunted hydrocephalus, such as ventriculomegaly, macrocephaly, or intracranial cyst. All ultrafast brain MRIs were evaluated by a certified neuroradiologist and a neurosurgeon. Ultrafast brain MRI was deemed of sufficient diagnostic value for these indications if no further standard brain MRI was required for the study indication or if additional imaging was performed for an alternate indication.

RESULTS

The radiology information system identified 800 patients who had undergone an ultrafast brain MRI during the study period. One hundred twenty-two of these patients had ventriculomegaly, macrocephaly, or intracranial cyst as the study indication. Twenty-one of the 122 patients were excluded due to insufficient follow-up. Of the remaining 101 patients, only 5 had a standard brain MRI for the same indication, with no additional clinically significant information identified on those studies.

CONCLUSIONS

These results suggest that ultrafast brain MRI is sufficient to evaluate ventriculomegaly, macrocephaly, or intracranial cyst. Ultrafast brain MRI is radiation- and sedation-free; therefore, we recommend its use as the primary screening neuroimaging study for these indications.

Two-dimensional plasmonic grating for increased quantum efficiency in midwave infrared nBn detectors with thin absorbers

We demonstrate a strategy for increasing the operating temperatures of nBn midwave infrared (MWIR) focal plane arrays, based on the use of two-dimensional plasmonic gratings to enhance the quantum efficiency (QE) of structures with very thin absorbers. Reducing the absorber volume correspondingly reduces the dark current in a diffusion-limited photodiode, while light trapping mediated by the plasmonic grating increases the net absorbance to maintain high QE. The plasmonically enhanced nBn MWIR sensors with absorber thicknesses of only 0.5 μm exhibit peak internal QEs as high as 57%, which enables a 5-fold reduction in dark current. Numerical simulations indicate the potential for further improvement.

How to Reduce Head CT Orders in Children with Hydrocephalus Using the Lean Six Sigma Methodology: Experience at a Major Quaternary Care Academic Children's Center

BACKGROUND AND PURPOSE

Lean Six Sigma methodology is increasingly used to drive improvement in patient safety, quality of care, and cost-effectiveness throughout the US health care delivery system. To demonstrate our value as specialists, radiologists can combine lean methodologies along with imaging expertise to optimize imaging elements-of-care pathways. In this article, we describe a Lean Six Sigma project with the goal of reducing the relative use of pediatric head CTs in our population of patients with hydrocephalus by 50% within 6 months.

MATERIALS AND METHODS

We applied a Lean Six Sigma methodology using a multidisciplinary team at a quaternary care academic children's center. The existing baseline imaging practice for hydrocephalus was outlined in a Kaizen session, and potential interventions were discussed. An improved radiation-free workflow with ultrafast MR imaging was created. Baseline data were collected for 3 months by using the departmental radiology information system. Data collection continued postintervention and during the control phase (each for 3 months). The percentage of neuroimaging per technique (head CT, head ultrasound, ultrafast brain MR imaging, and routine brain MR imaging) was recorded during each phase.

RESULTS

The improved workflow resulted in a 75% relative reduction in the percentage of hydrocephalus imaging performed by CT between the pre- and postintervention/control phases (Z-test, P = .0001).

CONCLUSIONS

Our lean interventions in the pediatric hydrocephalus care pathway resulted in a significant reduction in head CT orders and increased use of ultrafast brain MR imaging.

Subungual Penetration of Dibutyl Phthalate in Human Fingernails

Dibutyl phthalate (DBP) has a wide variety of manufacturing applications and is used in both commercial and consumer products. Results of animal reproductive toxicity and teratogenicity animal studies have not been consistent in identifying DBP as a reproductive toxicant. Expert reviews for its use in consumer products have consistently concluded that it is not a reproductive risk to consumers. Results from a subungual penetration study of 100% fluid DBP applied to human fingernails showed levels of penetration at the limits of chemical detection. Even if DBP penetrated the human fingernail, its rapid metabolism by the human body would prevent its having any toxic reproductive effects. Furthermore, DBP functions as a plasticizer in consumer products such as cosmetic nail products (nail polish, basecoats, topcoats, nail hardeners), resulting in its becoming unavailable for subungual penetration seconds after application of the cosmetic nail product since it is then trapped in the rapidly forming coating.

Failure of glove hole detection device for synthetic gloves

Holes in latex gloves can be reliably detected by commercially available electronic devices. The purpose of this study was to compare the performance of an electronic glove hole detection device using latex gloves to that of neoprene, vinyl, and nitrile latex-free gloves. The electronic hole detection device accurately detected holes in the latex gloves during the 2-h study. In contrast, the latex-free gloves were immediately conductive of electricity in the absence of holes. Consequently, electronic glove hole detection devices cannot be reliably used with latex-free gloves.

Ease of donning commercially available latex examination gloves

There are a wide variety of latex examination gloves now available for use by health care providers. A prospective randomized trial was completed to quantify the forces required to don a sample of seven cornstarch-lubricated gloves and 13 powder-free latex examination gloves. The data collected was analyzed by a 20 x 2 general factorial ANOVA, as well as two 1-way ANOVAs using a least significance difference post hoc test. Some powder-free gloves can be easily donned with dry or wet hands without tearing with forces comparable to those encountered with powdered gloves. With the advent of these powder-free examination gloves, powdered gloves can now be abandoned, protecting health professionals and patients from the dangers of absorbable dusting powders. Despite the dangers of the absorbable dusting powders and the Food and Drug Administration's requirement for labeling examination glove boxes, some manufacturers of powdered examination gloves do not appropriately label their boxes with a warning to the health professional and patient of the presence of powder.

Biomechanical performance of orthopedic gloves

The purpose of this study was to compare the biomechanical performance of commercially available orthopedic gloves to that of a single surgical glove, as well as a double glove system. The orthopedic gloves were found to be thicker than the single surgical glove. This increased thickness of the orthopedic glove was associated with a greater resistance to glove puncture. The thickest orthopedic gloves also had reduced tactile sensitivity when compared to the single surgical glove. In addition, the glove donning forces and glove hydration rates varied considerably. These latter biomechanical performance parameters were not significantly related to glove thickness. The double glove systems tested in this study had similar performance characteristics in regard to many of the orthopedic gloves. The glove donning forces for the double glove systems were the lowest of the gloves tested. In addition, the double glove systems displayed the greatest resistance to glove hydration of the gloves tested. Their performance in the glove hydration tests and the force required to don the double glove systems were much more desirable than any of the orthopedic gloves. The results of this study indicate that the double glove systems may provide a desirable alternative to the use of the single orthopedic gloves.

Kinetics and plasma concentrations of 26-hydroxycholesterol in baboons

26-Hydroxycholesterol (26OHC), a major oxysterol in human blood, is believed to play an important role in reverse cholesterol transport, bile acid formation, and regulation of various cellular processes. Using isotope dilution mass spectrometry, we measured plasma 26OHC concentrations in baboons fed either a high cholesterol/saturated fat (HC-SF) or normal chow diet. Plasma 26OHC levels in baboons were comparable to those reported for humans and were positively correlated with plasma cholesterol concentrations. Animals on the HC-SF diet had significantly higher 26OHC levels (0.274+/-0.058 microM, mean+/-S.D.) than those on the chow diet (0.156+/-0.046 microM). In separate experiments, [(3)H]26OHC was injected into four tethered baboons, and multiple blood samples drawn over a 1-h period were analyzed for [(3)H]26OHC and 26OHC. Fitting the specific radioactivity data to a two-pool compartmental model indicated a rapidly turning over plasma compartment (t(1/2) 2.9-6.0 min) and a second compartment with slow turnover (t(1/2) 76-333 min). The calculated 26OHC production rate was 2.5 micromol/kg body weight/day. Assuming all 26OHC is converted to bile acids, the 26OHC production rate corresponds to about 10% of total bile acid production in adult baboons. These results indicate that rapid turnover of plasma 26OHC at submicromolar concentrations could significantly contribute to bile acid synthesis.

A global inventory of hospitals using powder-free gloves: a search for principled medical leadership

Scientific experimental and clinical studies have demonstrated that cornstarch on surgical and examination gloves promotes disease by acting as a reactive foreign body in tissue and serving as a vector for latex allergy. Consequently, hospitals have selected an innovative glove selection program utilizing only powder-free gloves. Healthcare workers in emergency medical systems are now wearing powder-free, latex-free gloves to care for the growing number of patients sensitized to latex. A global Internet search has now identified 70 hospitals in the United States and three hospitals in Europe that use only powder-free gloves.

Trigeminal neuralgia: a diagnostic challenge

A 38-year-old white woman came to the emergency department complaining of severe, unilateral jaw pain. She had consulted her primary care physician and dentist without achieving the correct diagnosis or significant relief of her symptoms. The emergency physician made the diagnosis of trigeminal neuralgia by obtaining a history of severe paroxysmal ipsilateral facial pain activated by numerous facial stimuli. A light stimulation of the trigger point precipitated the pain. Her pain relief from carbamazepine lent further credence to the diagnosis of trigeminal neuralgia and appropriate referral to a neurosurgeon. Pain relief was ultimately achieved for the last 8 months by a neurectomy of the right infraorbital nerve.

Integrity of powder-free examination gloves to bacteriophage penetration

The purpose of this study was to compare the resistance to viral penetration of powder-free synthetic examination gloves with powder-free latex examination gloves commonly used in hospitals. Because these gloves had no holes, this study examined viral penetration through a membrane. Using a standard bacteriophage penetration model, no bacteriophage penetration was detected through the membrane for any of the gloves tested. The new powder-free nitrile and polyvinyl chloride synthetic examination gloves provided comparable resistance to viral penetration as did the powder-free latex examination gloves.

Biomechanical performance of examination gloves

The purpose of this study was to compare the biomechanical performance of new powder-free commercially available synthetic examination gloves to that of commercially available powder-free latex examination gloves. The synthetic gloves were significantly thinner than the latex gloves. Despite the decreased thickness, all three nitrile gloves, as well as the polyvinyl chloride glove, exhibited a greater resistance to glove puncture. The glove donning forces varied considerably among all gloves, and wet donning forces were greater than dry donning forces. Under dry conditions, the donning forces for the synthetic gloves were less than or equal to the forces for the latex gloves. Because of their increased puncture resistance and similar donning forces, synthetic gloves are a safe alternative to latex examination gloves.

Assessing the bioactivity of cosmetic products and ingredients

Cosmetic ingredients can produce physical effects on the skin as well as positive and negative bioactive effects. Such effects have now been identified, categorized and interpreted. Because of this ongoing research and increased understanding, cosmetics, especially skin care products, are being improved. Targeting specific bioactive effects from newly developed cosmetic products is now possible. This development is aided by refining and expanding existing instrumental analysis which is now capable of elucidating more detailed and statistically significant differences from the use of certain ingredients in cosmetics. However, the ultimate proof of these changes will remain the consumer response to such products. Physical effects and the positive and negative bioactive effects from specific cosmetic ingredients will be discussed in relationship to the anatomy, physiology and condition of human skin. Examples of selected cosmetic ingredients in relationship to the anatomy, physiology and condition of human skin will be given. Demonstrations of selected cosmetic ingredient effects will be by way of clinical observation, instrumental analysis and consumer evaluation.

Comparison testing of the irritancy of children's liquid bubble bath using a modified human repeat insult patch test

BACKGROUND

Bubble baths are common products used by parents with young children. Some dermatologists and pediatricians do not recommend the use of these products.

OBJECTIVE

The purpose of this study was to compare the irritancy of nine children's liquid bubble bath solutions.

METHODS

A modified human repeat insult patch test (HRIPT) was used to rank order the irritancy of nine bubble bath preparations. Erythema, scaling, and fissuring were evaluated at the patch test sites.

RESULTS

The nine products tested varied in their ability to cause irritation. Based on the degree of erythema, the least irritation was produced with Sesame Street Fresh Apple Splash bubble bath.

CONCLUSION

This study suggests that there are differences in the irritancy of brands of children's liquid bubble bath and that recommendations can be made by both dermatologists and pediatricians when parents choose to use these products on their children.

Prognostic patch testing: the other kind of patch test

Prognostic patch testing differs from diagnostic patch testing. Clinicians routinely perform diagnostic patch testing, but prognotic patch testing is the province of corporate research and development departments and, in the United States, contract laboratories. The three types of prognostic patch testing are described and referenced in the scientific and medical literature. A comparison among the three types of prognostic patch testing and diagnostic patch testing is provided. In addition, the variables in both prognostic and diagnostic patch testing are listed, as well as the types of ingredients and products routinely tested in prognostic patch testing.

Inadequate standard for glove puncture resistance: allows production of gloves with limited puncture resistance

The National Fire Protection Association has developed standards for glove puncture resistance using a metal puncture probe. Biomechanical performance studies have demonstrated that glove puncture resistance to the probe is significantly greater than that of the hypodermic needle, suggesting that these standards have no clinical relevance. These standards give a false sense of security to health care personnel and sanction the production and use of gloves that give inadequate protection. The result is potentially harmful for medical personnel.

Latex glove penetration by pathogens: a review of the literature

Universal precautions mandate the use of examination and surgical gloves to protect the health professional from contact with the HIV virus. The purpose of this paper is to provide a review of the literature on the barrier properties of examination and surgical gloves measured by water leakage and viral penetration. The literature data indicate that glove composition, glove manufacturer, glove design (examination vs. surgical), and mechanical manipulation had considerable influence on glove performance when tested for leakage and viral penetration. In general, latex gloves were found to be superior to vinyl gloves as barriers to water leakage and viral penetration.

Influence of latex glove hydration on bacteriophage penetration

The purpose of this study was to determine whether glove hydration influenced bacteriophage penetration. Using an electronic glove hole-detection device, one brand of latex glove was identified that hydrated rapidly (3.25 min +/- 0.71 min), while another brand was selected that resisted hydration (120 min +/- 0 min). Using a standard bacteriophage penetration model, the amount of bacteriophage penetration in both the rapidly hydrating gloves and the gloves that resisted hydration was extremely small and did not differ significantly from each other.

Dimensions of care in five United States nursing homes: identifying invisible work in care-giving

This article reports on a study carried out to identify components of practical knowledge, which is the knowledge that is used to guide decision-making and actions, used by care-givers in nursing homes. The practical knowledge behind the giving of care in the day-to-day activities in five nursing homes was studied and models for such care were developed. One finding from this study was that a large portion of the work of caring as known and understood by care-participants (patients, families, and nursing staff) was excluded from prescribed routines established by administration for care.

Preweaning diet programs postweaning plasma thyroxine concentrations in baboons

We tested the hypothesis that breast- and formula-feeding of infant baboons affect postweaning plasma thyroid hormone concentrations and that differences in thyroid hormone concentrations are associated with long-term effects of infant diet on lipoprotein concentrations and cholesterol metabolism. Newborn baboons were breast-fed (n = 12) or fed formulas with a high polyunsaturated/saturated (P/S) fat ratio (n = 11) or with a low P/S ratio (n = 12) similar to baboon breast milk. Baboons were weaned at 14 weeks of age to a high cholesterol, saturated fat diet. Plasma thyroid hormone concentrations were measured in this group of baboons until about 223 weeks of age. Thyroid hormones were also measured at 400 weeks in a second group of adult baboons (n = 80) that as infants were either breast-fed or fed formulas with varying levels of cholesterol. Baboons breast-fed as infants averaged 11% higher (P < 0.03) thyroxine (T4) concentrations from 34 to 400 weeks of age compared with those fed formulas. From 70 to 400 weeks of age breast-fed baboons had 10% lower T3/T4 ratios (P < 0.03). Breast- versus formula-feeding did not affect postweaning T3 and fT3 concentrations. Postweaning thyroid hormone concentrations were not significantly affected by the P/S ratio or the cholesterol level of the infant formulas. The rank correlation of the means of the sire progeny groups for T4 and HDL-C concentrations was statistically significant (rn = -0.83; P < 0.05). Partial correlations of T4 concentrations with body weight, feed intake, or measures of cholesterol metabolism were not significant. T4 concentrations were significantly correlated with T3 concentrations (r = 0.42; P < 0.02), and T3 concentrations were correlated with bile acid synthesis rate (r = 0.47; P < 0.01), acyl-CoA cholesterol acyltransferase (r = 0.66; P < 0.001), and plasma HDL1-C levels (r = -0.49; P < 0.007). These effects suggest that altered thyroid hormone homeostasis may partially mediate the long-term differences in cholesterol metabolism caused by breast-versus formula-feeding.

Effect of estrogen and progesterone on the expression of hepatic and extrahepatic sterol 27-hydroxylase in baboons (Papio sp)

Sterol 27-hydroxylase plays an important role in cholesterol metabolism in hepatic and extrahepatic tissues. To determine whether female sex steroid hormones influence its expression, we measured plasma and hepatic 27-hydroxycholesterol, hepatic mRNA levels, activity of sterol 27-hydroxylase, and adrenal mRNA levels of this enzyme in baboons (n = 6 per group) treated with placebo, estrogen, estrogen + progesterone, and progesterone. We also measured hepatic cholesterol concentration and hepatic acyl coenzyme A:cholesterol acyltransferase (ACAT) activity to determine their relationship with hepatic sterol 27-hydroxylase activity. Plasma 27-hydroxycholesterol concentration was increased by estrogen and estrogen + progesterone and was negatively correlated with plasma (P = .090) and LDL (P = .026) cholesterol concentrations. Similarly, hepatic sterol 27-hydroxylase activity was increased by estrogen and estrogen + progesterone and was negatively correlated with plasma (P = .056) and LDL (P = .052) cholesterol concentrations but was positively correlated with hepatic and plasma 27-hydroxycholesterol concentrations (P < .001). Hepatic ACAT activity was increased by progesterone (P < .004) and was positively correlated with plasma (P = .002) and LDL (P = .009) cholesterol concentrations but was negatively correlated with hepatic sterol 27-hydroxylase activity (P = .035). Hepatic and adrenal gland mRNA levels for sterol 27-hydroxylase were increased by estrogen alone or in combination with progesterone (P < .05). Hepatic sterol 27-hydroxylase activity was positively correlated with hepatic mRNA levels (P < .001), an observation suggesting that estrogen increases the activity of sterol 27-hydroxylase by increasing its synthesis. Hepatic cholesterol concentration was not influenced by the hormone treatment. These observations suggest that estrogen alone or in combination with progesterone increases the synthesis of sterol 27-hydroxylase in hepatic and extrahepatic tissues, and the increased activity of hepatic sterol 27-hydroxylase resulting from the increased synthesis is associated with a hypolipidemic effect on plasma LDL levels. Furthermore, progesterone alone increases the hepatic ACAT activity, but given in combination with estrogen progesterone does not have the same effect on hepatic ACAT activity. The effect of estrogen on hepatic ACAT activity may be mediated by sterol 27-hydroxylase and its effect on cholesterol metabolism (decreased cholesterol synthesis and increased output of cholesterol in the bile) in liver.

Early determinants of adult metabolic regulation: effects of infant nutrition on adult lipid and lipoprotein metabolism

In a series of experiments over the past 20 years, we have demonstrated long-term deferred effects of infant nutrition, particularly breast- as compared with formula-feeding and overfeeding as compared with normal or underfeeding, on serum HDL-cholesterol concentrations, adiposity, and atherosclerosis in the baboon, a large nonhuman primate. Low HDL-cholesterol levels and obesity are associated with accelerated progression of atherosclerosis and with increased risk of coronary heart disease in humans. We have observed other deferred effects of infant nutrition on bile acid metabolism, enzyme activities, and water and electrolyte balance, some of which may be physiologically related to HDL-cholesterol levels or to adiposity. The occurrence of these deferred effects suggests that infant nutrition may program other metabolic systems for life, and that these effects may contribute to other chronic diseases of adults. Although our understanding of the mechanisms by which infant diet regimens affect adult metabolism is meager, it is important to identify these mechanisms because they are likely to provide valuable clues to the causes and ultimately may contribute to the long-range prevention of those diseases.

Triiodothyronine accelerates maturation of bile acid metabolism in infant baboons

We tested the hypothesis that triiodothyronine (T3) treatment accelerates the early postnatal maturation of bile acid metabolism in the baboon. Infant baboons were implanted with 21-day-release pellets containing T3 (n = 12), a placebo pellet (n = 6), or no pellet (n = 13). T3 treatment increased plasma T3 concentrations from 3.0 to 5.0 nmol/l between birth and 15 wk of age. At 15 wk of age, bile acid pool sizes, fractional turnover rates (FTR), and synthetic rates were determined by an isotope-dilution method with 3H- and 14C-labeled cholic (CA) and chenodeoxycholic acid (CDCA). T3 treatment increased CA pool size by 47% and CA synthetic rate by 37% but did not significantly affect CDCA pool size or synthetic rate. Consequently CA-to-CDCA pool size ratio (0.77 vs. 0.42) and biliary CA-to-CDCA concentration ratio (0.88 vs. 0.46) were higher in the T3-treated infants than in combined placebo-treated and nontreated control infants. T3 treatment did not affect the bile acid glycine-to-taurine conjugate ratio, CA FTR, or CDCA pool size, FTR, and synthetic rate. T3 treatment lowered plasma high-density lipoprotein fraction 2 and 3 cholesterol concentrations by 22 and 40%, respectively. T3 treatment also increased hepatic low-density lipoprotein receptor mRNA levels but did not affect plasma low-density lipoprotein cholesterol concentrations. We conclude that modest elevation of plasma T3 during the preweaning period increases the CA-to-CDCA ratio at the end of the preweaning period to near adult values.

Differences in cholesterol metabolism in juvenile baboons are programmed by breast- versus formula-feeding

We estimated the effects of breast- and formula-feeding on cholesterol and bile acid metabolism for 1.5 years after weaning in 35 newborn baboons that were breast-fed (n = 12) or fed one of two formulas with high (n = 11) or low (n = 12) polyunsaturated/saturated (P/S) fatty acid composition. Infants were weaned at 15 weeks to a high cholesterol, saturated fat diet. Because formula P/S ratio did not affect any variable for 1.5 years after weaning, the data were averaged for the two formula groups. After weaning, serum cholesterol and lipoprotein cholesterol concentrations among the infant diet groups were not different until after 52 weeks of age. From 70 to 97 weeks of age, serum cholesterol and high density lipoprotein-2 (HDL2)-cholesterol (HDL2-C) concentrations were lower (P < 0.04) among baboons that were breast-fed as infants compared with those fed formulas. We observed no significant postweaning differences in low density lipoprotein (LDL)-C, HDL3-C, or serum apolipoprotein A-I, B, or E concentrations. At 97 weeks of age baboons that were breast-fed until 15 weeks compared with those formula-fed had a 25% lower total bile acid synthetic rate (36.6 vs. 48.6 mumol/day per kg body weight, P < 0.02) due principally to a 29% lower cholic acid synthetic rate (23.2 vs 32.5 mumol/day per kg body weight, P < 0.004). Baboons breast-fed as infants had a 44% higher hepatic LDL-receptor mRNA concentration than those formula-fed (1.45 vs. 1.01 pg mRNA/micrograms total RNA, P < 0.003).(ABSTRACT TRUNCATED AT 250 WORDS)

Amino acid composition of the milk of some mammalian species changes with stage of lactation

To determine whether the amino acid composition of milk changes during lactation, we compared the amino acid pattern (concentration of each individual amino acid relative to the total amino acid concentration) of colostrum with that of mature milk in six mammalian species. In the human, horse, pig and cow, the pattern of amino acids changed between colostrum and mature milk: glutamate, proline, methionine, isoleucine and lysine increased; cystine, glycine, serine, threonine and alanine decreased. In these four species, the total amino acid concentration also decreased 75% between colostrum and mature milk. In the baboon (Papio cynocephalus anubis and Papio cynocephalus anubis/Papio cynocephalus cynocephalus) and rhesus monkey (Macaca mulatta), however, there was little change in the pattern of amino acids between colostrum and mature milk, and total amino acid concentration decreased only about 25% between colostrum and mature milk. Mature milk rather than colostrum was the most similar among the three primates in both amino acid pattern and total amino acid concentration. We conclude, in those species in which total amino acid concentrations decline substantially between colostrum and mature milk, amino acid patterns also change. The presence of a change in amino acid pattern and total amino acid concentration during lactation appears to be unrelated to phylogenetic order.

Amino acid composition of human milk is not unique

To determine whether the amino acid pattern of human milk is unique, we compared the amino acid pattern of human milk with the amino acid patterns of the milks of great apes (chimpanzee and gorilla), lower primates (baboon and rhesus monkey) and nonprimates (cow, goat, sheep, llama, pig, horse, elephant, cat and rat). Amino acid pattern was defined as the relative proportion of each amino acid (protein-bound plus free) (in mg) to the total amino acids (in g). Total amino acid concentration was lower in primate milk than in nonprimate milk. There were commonalities in the overall amino acid pattern of the milks of all species sampled; the most abundant amino acids were glutamate (plus glutamine, 20%), proline (10%) and leucine (10%). Essential amino acids were 40%, branched-chain amino acids 20%, and sulfur amino acids 4% of the total amino acids. The amino acid pattern of human milk was more similar to those of great apes than to those of lower primates. For example, cystine was higher and methionine was lower in primate milks than in nonprimate milks, and in great ape and human milks than in lower primate milks. Because the milk amino acid patterns of the human and elephant, both slow-growing species, were dissimilar, the amino acid pattern of human milk seems unrelated to growth rate.

Safety and efficacy of a topical anesthetic for neonatal circumcision

OBJECTIVE

Circumcision is a common neonatal surgical procedure routinely performed without the use of anesthesia. The purpose of this study was to evaluate the safety and efficacy of topical lidocaine cream as an anesthetic for circumcision.

METHODS

Thirty newborns were studied in a randomized, double-blind, placebo-controlled study; 15 received a topical 30% lidocaine cream and 15 received the cream base alone. Vital signs were recorded, and preoperative and postoperative serum beta-endorphin and lidocaine concentrations were measured. A videotape of the newborn was used to score behavioral changes.

RESULTS

Comparisons of the vital signs precircumcision and postcircumcision showed no differences between the placebo and treatment groups, with the exception of mean systolic blood pressure, which significantly increased in the placebo-treated newborns (P < .05). Serum beta-endorphin concentrations increased postoperatively in 11 of 15 subjects receiving placebo, but decreased or remained unchanged in 10 of 15 subjects receiving lidocaine (P = .03, Fisher's exact test). When stress-related behaviors in the precircumcision and post-circumcision periods were compared, the mean increase in their occurrence was greater in the placebo than in the treatment group. There was no significant absorption of lidocaine as measured in the serum.

CONCLUSION

Topical application of a 30% lidocaine cream as used in this study may be a safe and efficacious anesthetic for circumcision.

Preweaning diet affects bile lipid composition and bile acid kinetics in infant baboons

We tested, with 14-wk-old baboons before weaning, the hypothesis that bile acid metabolism is differentially affected by breast feeding or by feeding formulas with a high polyunsaturated:saturated fatty acid ratio or with a low ratio, similar to that of breast milk. Bile lipid content, bile acid pool size, fractional turnover rate, synthetic rate and conjugate composition were measured in a single bile sample 9 d after an injection on d 1 of a mixture of [14C]cholic and [14C]chenodeoxycholic acids and an injection of a mixture of [3H]cholic acid and [3H]chenodeoxycholic acid on d 8. The principal biliary bile acid was chenodeoxycholic acid. The only difference in chenodeoxycholic acid metabolism among the infant diet groups was a lower chenodeoxycholic acid synthetic rate in baboons fed the low polyunsaturated:saturated formula compared with those fed the high polyunsaturated:saturated formula or breast-fed. Cholic acid metabolism was significantly affected by infant diet: breast-fed infants had a smaller cholic acid pool size, lower cholic acid percentage of total bile acids, higher cholic acid glycine:taurine conjugate ratio and larger cholic acid fractional turnover rate than formula-fed animals. The polyunsaturated:saturated fatty acid ratio in the formulas did not significantly affect these variables. These results show that differences in bile acid metabolism between breast- and formula-fed infant baboons are limited principally to cholic acid. These differences likely are due to factors other than fatty acid saturation.

Effects of dietary cholesterol, type of fat, and sex on bile lipid composition of adult baboons

We measured the effects of dietary cholesterol (0.24 vs 0.0024 mg/kJ), type of dietary fat [saturated, a ratio of polyunsaturated to saturated fatty acids (P:S) of 0.37, vs unsaturated (P:S of 2.2)], and sex on biliary lipid and bile acid conjugate composition of 80 adult pedigreed baboons. From these data we calculated the bile cholesterol saturation index and the bile acid hydrophobicity index. Dietary cholesterol significantly increased the bile cholesterol concentration by 25% and the bile cholesterol saturation index by 15%, but did not significantly affect the bile acid conjugate composition or the bile acid hydrophobicity index. Diets high in saturated fatty acid compared with unsaturated fatty acid significantly decreased the bile cholesterol concentrations by 26% and the saturation index by 23%. Saturated fatty acid also decreased the proportion of hydrophobic bile acids and lowered the bile hydrophobicity index. Male baboons had a higher cholesterol saturation index and a lower hydrophobicity index than females. Dietary cholesterol and saturated fatty acid independently influence the bile lipid composition and the cholesterol saturation index.

Dietary cholesterol and type of fat differentially affect cholesterol metabolism and atherosclerosis in baboons

This study was designed to determine the differences in cholesterol metabolism due to dietary cholesterol and type of fat in adult baboons. From weaning at 16 wk to 7-8 y of age, 80 baboons were fed one of four diets: high cholesterol (0.24 mg/kJ) or low cholesterol (0.0024 mg/kJ) with 40% of energy from saturated fat [polyunsaturated/saturated fatty acid ratio (P/S) = 0.37] or unsaturated fat (P/S = 2.1). High cholesterol and saturated fat independently raised serum lipoprotein and apolipoprotein concentrations to about the same extent. The liver cholesterol concentration of baboons fed high cholesterol diets was 23% higher than that of baboons fed low cholesterol. High dietary cholesterol also increased bile cholesterol concentration by 25%, the neutral steroid excretion rate by 66% and the bile acid excretion rate by 30%. With feeding of saturated fat, compared with unsaturated fat, liver cholesterol was 24% lower, bile cholesterol 26% lower and the neutral steroid excretion rate 12% lower. Dietary cholesterol greatly suppressed whole-body cholesterol synthesis, but type of fat did not affect cholesterol synthesis rate. These results suggest that dietary cholesterol and saturated fat increase plasma lipoprotein concentrations through different physiological mechanisms.

Facial moisturizers and wrinkles

Facial moisturizers are part of the cosmetic category known as skin care products, which also includes other facial products such as astringents, toners, soaps, and bath products. This article describes the composition and pharmaceutics of currently marketed moisturizers, the use of fragrances and preservatives in these products, how cosmetic facial moisturizers work on wrinkles, sunscreen-containing facial moisturizers, and the Food and Drug Administration's record regulating drug claims for anti-wrinkling products.

Effect of energy intake on postprandial plasma hormones and triglyceride concentrations in infant female baboons (Papio species)

We previously reported that female baboons overfed during infancy were not fatter at weaning, but developed hypertrophic obesity after puberty. To clarify the mechanisms of this dietary effect on adipocyte hypertrophy, we determined the effects of infant overfeeding on preweaning plasma hormone and triglyceride levels and their relationship with fat cell volume at weaning (19 weeks of age). Newborn female baboons from 3 sires and 24 dams were fed either 280 kilojoules (normally fed; n = 12) or 395 kilojoules (overfed; n = 10) per 100 g Similac formula for 18 weeks. Both formulas contained 9.2%, 43.1%, and 48.5% of calories as protein, carbohydrate, and fat, respectively. During the first 9 weeks, overfed infants had significantly higher fasting and postprandial insulin, total T3, and free T3 concentrations; lower cortisol levels; and lower excretion of urinary 17-hydroxycorticosteroids (17-OHCS) than normally fed infants. These effects were no longer significant at 17-18 weeks. Infant diet did not influence fasting and postprandial plasma triglyceride levels, and fat cell volume was not influenced by energy intake. However, fat cell volume was positively associated with postprandial triglyceride concentrations and inversely associated with postmeal nadir cortisol levels. These results demonstrate that infant overfeeding initiates early alterations in insulin, T3, free T3, and cortisol, but these effects persist only as long as there is a significant increase in energy intake.

Maternal weight and sire group, not caloric intake, influence adipocyte volume in infant female baboons

We tested the hypothesis that overfeeding with a high caloric (concentrated) formula increases growth without influencing adipocyte volume in preweaning infant baboons. Female infant baboons from three sires and 25 dams were fed either 67.5 kcal (normal formula) or 94.5 kcal (concentrated formula)/100 g Similac formula. Immediately before weaning (19 wk), adipocyte volume was measured in biopsied adipose tissue from omentum, flank, and popliteal depots. From birth until weaning, infants fed the concentrated formula consumed 20% more total calories, averaged 15% more calories/kg/wk, and gained 14% more weight than normally fed infants. Adipocyte volume differed significantly among different sites (omentum greater than popliteal greater than flank) and among different sire groups. Increased caloric intake alone did not increase adipocyte volume. There was a small but significant sire by infant formula interaction on adipocyte volume. When fed the concentrated formula, progeny from one sire had larger adipocytes than normally fed infants, whereas progeny from the other two sires had smaller adipocytes or adipocytes that were comparable to infants fed normal formula. Variability in adipocyte volume at 19 wk of age was best accounted for by maternal weight and sire group (omentum R2 = 0.334, p = 0.026; flank R2 = 0.532, p = 0.01; popliteal R2 = 0.482, p = 0.01) and not by caloric intake. These results suggest that the level of triglyceride deposition into adipocytes attained during preweaning growth is determined to a greater extent by genetic and other factors rather than caloric intake.