Effects of motion and audio-visual redundancy on upright and inverted face and feature preferences in 4-13-month old pre- and full-term NICU graduates

NICU infants are reported to have diminished social orientation and increased risk of socio-communicative disorders. In this eye tracking study, we used a preference for upright compared to inverted faces as a gauge of social interest in high medical risk full- and pre-term NICU infants. We examined the effects of facial motion and audio-visual redundancy on face and eye/mouth preferences across the first year. Upright and inverted baby faces were simultaneously presented in a paired-preference paradigm with motion and synchronized vocalization varied. NICU risk factors including birth weight, sex, and degree of CNS injury were examined. Overall, infants preferred the more socially salient upright faces, making this the first report, to our knowledge, of an upright compared to inverted face preference among high medical risk NICU infants. Infants with abnormalities on cranial ultrasound displayed lower social interest, i.e. less of a preferential interest in upright faces, when viewing static faces. However, motion selectively increased their upright face looking time to a level equal that of infants in other CNS injury groups. We also observed an age-related sex effect suggesting higher risk in NICU males. Females increased their attention to the mouth in upright faces across the first year, especially between 7-10 months, but males did not. Although vocalization increased diffuse attention toward the screen, contrary to our predictions, there was no evidence that the audio-visual redundancy embodied in a vocalizing face focused additional attention on upright faces or mouths. This unexpected result may suggest a vulnerability in response to talking faces among NICU infants that could potentially affect later verbal and socio-communicative development.

Gut microbiome modulates response to anti-PD-1 immunotherapy in melanoma patients

Preclinical mouse models suggest that the gut microbiome modulates tumor response to checkpoint blockade immunotherapy; however, this has not been well-characterized in human cancer patients. Here we examined the oral and gut microbiome of melanoma patients undergoing anti-programmed cell death 1 protein (PD-1) immunotherapy (n = 112). Significant differences were observed in the diversity and composition of the patient gut microbiome of responders versus nonresponders. Analysis of patient fecal microbiome samples (n = 43, 30 responders, 13 nonresponders) showed significantly higher alpha diversity (P < 0.01) and relative abundance of bacteria of the Ruminococcaceae family (P < 0.01) in responding patients. Metagenomic studies revealed functional differences in gut bacteria in responders, including enrichment of anabolic pathways. Immune profiling suggested enhanced systemic and antitumor immunity in responding patients with a favorable gut microbiome as well as in germ-free mice receiving fecal transplants from responding patients. Together, these data have important implications for the treatment of melanoma patients with immune checkpoint inhibitors.

Pancreas-After-Islet Transplantation in Nonuremic Type 1 Diabetes: A Strategy for Restoring Durable Insulin Independence

Islet transplantation offers a minimally invasive approach for β cell replacement in diabetic patients with hypoglycemic unawareness. Attempts at insulin independence may require multiple islet reinfusions from distinct donors, increasing the risk of allogeneic sensitization. Currently, solid organ pancreas transplant is the only remaining surgical option following failed islet transplantation in the United States; however, the immunologic impact of repeated exposure to donor antigens on subsequent pancreas transplantation is unclear. We describe a case series of seven patients undergoing solid organ pancreas transplant following islet graft failure with long-term follow-up of pancreatic graft survival and renal function. Despite highly variable panel reactive antibody levels prior to pancreas transplant (mean 27 ± 35%), all seven patients achieved stable and durable insulin independence with a mean follow-up of 6.7 years. Mean hemoglobin A1c values improved significantly from postislet, prepancreas levels (mean 8.1 ± 1.5%) to postpancreas levels (mean 5.3 ± 0.1%; p = 0.0022). Three patients experienced acute rejection episodes that were successfully managed with thymoglobulin and methylprednisolone, and none of these preuremic type 1 diabetic recipients developed stage 4 or 5 chronic kidney disease postoperatively. These results support pancreas-after-islet transplantation with aggressive immunosuppression and protocol biopsies as a viable strategy to restore insulin independence after islet graft failure.

Effect of accommodating sucking and nosing on the behaviour of artificially reared piglets

Neonatal piglets are often used in biomedical research applications that require artificial rearing. Social housing can be problematic because the piglets develop belly nosing, navel and ear sucking that can result in injury. Our objective was to determine the effectiveness of using feeding devices that provide various opportunities for sucking and nosing behaviour on reducing piglet-directed behaviour of group-housed laboratory piglets. Fifteen piglets were used in each of four trials. The piglets nursed their dam for approximately 72 h to obtain passive immunity before transfer to a laboratory facility where they were allotted, five per group, to one of three stainless steel isolator units. Each unit featured a different style of feeding system for the delivery of milk replacer: a plastic trough (T), a nipple (N) mounted on a smooth plexiglass wall, or a nipple mounted on a pliant bag of sterile water (artificial udder [AU]). Each system had five feeding spaces so that all piglets fed simultaneously. Milk was provided at 6-h intervals, and behaviour was recorded on alternate days for 12 days post-weaning. Although trough-fed piglets began to eat much sooner than those piglets fed from nipples, time spent nosing, chewing or sucking on pen-mates and belly nosing were markedly higher in T piglets than in either N or AU, overall (mean: P <0.05) and over time (quadratic: P <0.05). Over time, N piglets developed a stereotypic snout rubbing on the wall behind the nipples, while AU piglets massaged and often fell asleep in contact with the udder from day 2 of the trial. Resting patterns were also affected. N and AU piglets settled down to rest more quickly (P <0.01) and spent significantly more time resting in the hour following feeding than T piglets (P <0.05). A feeding device that accommodates both sucking and massage can significantly reduce piglet-directed behaviour and may facilitate social housing of artificially reared piglets.

Metallothionein as a clonable tag for protein localization by electron microscopy of cells

A benign, clonable tag for the localization of proteins by electron microscopy of cells would be valuable, especially if it provided labelling with high signal-to-noise ratio and good spatial resolution. Here we explore the use of metallothionein as such a localization marker. We have achieved good success with desmin labelled in vitro and with a component of the yeast spindle pole body labelled in cells. Heavy metals added after fixation and embedding or during the process of freeze-substitution fixation provide readily visible signals with no concern that the heavy atoms are affecting the behaviour of the protein in its physiological environment. However, our methods did not work with protein components of the nuclear pore complex, suggesting that this approach is not yet universally applicable. We provide a full description of our optimal labelling conditions and other conditions tried, hoping that our work will allow others to label their own proteins of interest and/or improve on the methods we have defined.

Vascular neoplasm or pseudovascular nevus? Potential pitfalls in diagnosis

Melanocytic nevi, on histopathologic evaluation, occasionally contain slit-like clefts or spaces that may resemble vascular or lymphatic spaces. The spaces may contain blood or, perhaps more concerning, nests of melanocytes that could suggest lymphatic invasion of melanoma. When lined by melanocytes rather than true endothelium, these pseudovascular spaces within melanocytic nevi are generally attributable to tissue processing artifact. When the space in question is pronounced, a proper diagnostic work-up is prudent in order to exclude a true vascular neoplasm or melanoma. In this case series we present several melanocytic lesions with prominent vascular-appearing spaces that warranted further investigation.

Teaching behavior modification to nonprofessionals

Two instructional methods (role playing and lecture) were compared in evaluating the effectiveness of teaching behavior modification to institutional attendants. Pre- and post-test measures were obtained for two major outcome variables: (1) knowledge of behavior modification principles and (2) ratings of ability to apply behavior modification techniques. Results indicated that role playing was more effective in teaching behavior modification skills while the lectures were more effective in teaching principles of behavior modificaiton.

Belly-nosing in early-weaned piglets is not influenced by diet quality or the presence of milk in the diet

Early weaning of piglets can lead to an increase in belly-nosing and other oral-nasal behavior (nosing, chewing, or sucking other piglets), but the causative factors involved in these behavior patterns are largely unknown. Because these behavior patterns resemble massaging the udder and sucking, they may be associated with feeding. The objectives of this study were to determine any effect of diet quality or the presence of milk in the diet on belly-nosing behavior of piglets weaned at 14 to 18 d. During the first 2 wk after weaning, piglets were fed diets differing in quality and inclusion of milk products. Six replicates of eight piglets per replicate, blocked by initial body weight, (n = 192) were offered one of four dietary treatments: HQM: high quality, high in milk products; HQ: high quality, no milk products; PQ: poor quality, no milk products; HQ+MR: high quality, no milk products (as HQ) sprayed with milk replacer five times daily. Thereafter, the piglets were fed a standard nursery diet. Feed intake was measured daily for wk 1 and again at the end of wk 2. Behavior was recorded every 5 min during two 4-h periods on d 2 to 7, 10, 14, 17 and 21 after weaning. Dietary treatment influenced ADFI and ADG during wk 1. Average daily feed intake (P < 0.05) and ADG (P < 0.05) of piglets on PQ were less than those of piglets on the other treatments. During wk 2, ADFI (P > 0.10) and ADG (P > 0.10) were the same across all treatments. Overall, ADFI was not influenced by the inclusion of milk products in the diet or the addition of milk replacer (P > 0.10); however, ADG was. Piglets on HQM had higher ADG than those on HQ during wk 2 (P < 0.05) and 3 after weaning (P < 0.05). However, milk replacer did not influence ADG (P > 0.10). Although the dietary treatments did affect ADFI and ADG, there were no effects on any behavior pattern recorded, including time spent at the feeder (P > 0.10). Lower weight-for-age piglets performed more oral-nasal behavior, in total, than higher weight-for-age piglets (P < 0.03). Neither feeding a poor-quality diet nor the presence of milk in the diet had an effect on belly-nosing or other oral-nasal behavior patterns during the first 3 wk after weaning. Belly-nosing does not seem to be associated with feeding.

Therapeutic effects of oral zinc in acute and persistent diarrhea in children in developing countries: pooled analysis of randomized controlled trials

BACKGROUND

Zinc deficiency is prevalent in children in developing countries. Supplemental zinc provides therapeutic benefits in diarrhea.

OBJECTIVE

We sought to measure the effect of supplemental zinc given with oral rehydration therapy during recovery from acute or persistent diarrhea.

DESIGN

We conducted pooled analyses including all available published and unpublished randomized controlled trials of the effects of supplementary oral zinc in children aged <5 y with acute or persistent diarrhea. We used Cox survival regression analysis to evaluate the overall effect of zinc on continuation of diarrhea and possible differential effects in subgroups divided by sex, age, weight-for-height, and initial plasma zinc concentration. Dichotomous outcomes were analyzed by logistic regression. To assess the effects of excluding studies without original data from the pooled analyses, effect-size was estimated for all studies by using random-effects models.

RESULTS

Zinc-supplemented children had a 15% lower probability of continuing diarrhea on a given day (95% CI: 5%, 24%) in the acute-diarrhea trials and a 24% lower probability of continuing diarrhea (95% CI: 9%, 37%) and a 42% lower rate of treatment failure or death (95% CI: 10%, 63%) in the persistent-diarrhea trials. In none of the subgroup analyses were the 2 subgroups of each pair significantly different from each other; however, in persistent diarrhea there tended to be a greater effect in subjects aged <12 mo, who were male, or who had wasting or lower baseline plasma zinc concentrations.

CONCLUSION

Zinc supplementation reduces the duration and severity of acute and persistent diarrhea.

The use of herbal teas and remedies in Jamaica

We investigated the prevalence of the use of herbs among adults and children in Jamaica in 1996. Two concurrent surveys were conducted in randomly selected urban and rural areas: among adults and among caretakers of young children. From over 90% of the selected households, all caretakers of children under 6 years and one randomly selected adult (18 years or older) were interviewed using structured questionnaires. The 457 adults reportedly used 156 types of herbs: a mean of 6 +/- 3 (mean +/- standard deviation) by the urban adults, and 10 +/- 6 by the rural adults (t-test, p < 0.001). Almost 100% of respondents had at some time used herbs for teas or for treating illnesses. The most common method of preparation was by infusion or boiling in water, then adding sugar. Urban respondents, women and those who were employed were more likely to buy medicines than to use herbal remedies. One hundred and sixty-seven caretakers of 203 children under 6 years were interviewed. The mean number of herbs given to each child was between 2 and 3. The most common herbs were introduced within the first 6 months of life. Many caretaker factors were associated with herbal use. Public health implications include the potential toxicity of some herbs, the possibility that herbal teas given to young children may displace more nutritious foods and delay presentation to health care facilities. The findings will allow policy makers to target those most likely to use herbal preparations or to give them to young children, and target herbs to be analyzed for toxic or beneficial properties.

Aberrant pH of melanosomes in pink-eyed dilution (p) mutant melanocytes

In past studies, we cloned the mouse p gene and its human homolog P, which is associated with oculocutaneous albinism type 2. Both mouse and human genes are expressed in melanocytes and encode proteins predicted to have 12 membrane-spanning domains with structural homology to known ion transporters. We have also demonstrated that the p protein is localized to the melanosomal membrane and does not function as a tyrosine transporter. In this study, immunohistochemistry and confocal microscopy were used to show that the p protein plays an important role in the generation or maintenance of melanosomal pH. Melanosomes (and their precursor compartments) were defined by antiserum directed against the melanosomal marker tyrosinase related protein 1. Acidic vesicles were identified by 3-(2, 4-dinitroanilino)-3'-amino-N-methyldipropylamine incorporation, visualized with anti-dinitrophenol. In C57BL/6+/+ (wild-type) melanocytes, 94.2% of vesicles demonstrated colocalization of tyrosinase related protein 1 and 3-(2, 4-dinitroanilino)-3'-amino-N-methyldipropylamine, indicating that almost all melanosomes or their precursors were acidic. By contrast, only 7%-8% of the staining vesicles in p mutant cell lines (pJ/pJ and pcp/p6H) showed colocalization of tyrosinase related protein 1 and 3-(2,4-dinitroanilino)-3'-amino-N-methyldipropylamine. Thus, without a functional p protein, most melanosomes and their precursors are not acidic. As mammalian tyrosinase activity in situ is apparently dependent on low pH, we postulate that in the absence of a low pH environment brought about by ionic transport mediated by the p protein, tyrosinase activity is severely impaired, leading to the minimal production of melanin that is characteristic of p mutants. Additionally (or alternatively), an abnormal pH may also impair the assembly of the normal melanogenic complex.

Prevention of diarrhea and pneumonia by zinc supplementation in children in developing countries: pooled analysis of randomized controlled trials. Zinc Investigators' Collaborative Group

OBJECTIVES

This study assessed the effects of zinc supplementation in the prevention of diarrhea and pneumonia with the use of a pooled analysis of randomized controlled trials in children in developing countries.

STUDY DESIGN

Trials included were those that provided oral supplements containing at least one half of the United States Recommended Daily Allowance (RDA) of zinc in children <5 years old and evaluated the prevention of serious infectious morbidity through household visits. Analysis included 7 "continuous" trials providing 1 to 2 RDA of elemental zinc 5 to 7 times per week throughout the period of morbidity surveillance and 3 "short-course" trials providing 2 to 4 RDA daily for 2 weeks followed by 2 to 3 months of morbidity surveillance. The effects on diarrhea and pneumonia were analyzed overall and in subgroups defined by age, baseline plasma zinc concentration, nutritional status, and sex. The analysis used random effects hierarchical models to calculate odds ratios (OR) and 95% CIs.

RESULTS

For the zinc-supplemented children compared with the control group in the continuous trials, the pooled ORs for diarrheal incidence and prevalence were 0.82 (95% CI 0.72 to 0.93) and 0.75 (95% CI 0.63 to 0.88), respectively. Zinc-supplemented children had an OR of 0.59 (95% CI 0.41 to 0.83) for pneumonia. No significant differences were seen in the effects of the zinc supplement between the subgroups examined for either diarrhea or pneumonia. In the short-course trials the OR for the effects of zinc on diarrheal incidence (OR 0.89, 95% CI 0.62 to 1.28) and prevalence (OR 0.66, 95% CI 0.52 to 0.83) and pneumonia incidence (OR 0.74, 95% CI 0.40 to 1.37) were similar to those in the continuous trials.

CONCLUSIONS

Zinc supplementation in children in developing countries is associated with substantial reductions in the rates of diarrhea and pneumonia, the 2 leading causes of death in these settings.

In vivo evaluation of a novel epitope-tagged human factor VIII-encoding adenoviral vector

Haemophilia A is caused by a deficiency in coagulation factor VIII (FVIII) and is an attractive target for gene therapy. Adenoviral vectors encoding a human B-domain deleted (BDD) FVIII cDNA have been shown previously to mediate expression of high levels of human FVIII and correct the bleeding defect in haemophiliac mice and dogs. While vector assessment in a non-human primate model would have a significant preclinical benefit, a haemophiliac non-human primate model is not available, and assays that distinguish human FVIII from monkey FVIII have not been developed successfully. As a first step to enable vector evaluation in non-human primates, we have constructed an epitope-tagged FVIII molecule by the addition of 16 amino-acids to the carboxy terminus of the BDD protein (BDD-E). Following vector administration to normal mice, therapeutic levels of BDD-E FVIII were expressed for at least 20 weeks. Treatment of haemophiliac mice revealed that the BDD-E protein was biologically active in vivo. To distinguish the BDD-E protein from non-human primate FVIII, a sensitive immunoprecipitation/Western assay was developed that reproducibly detected 1 ng mL-1 of the epitope-tagged human FVIII in the presence of monkey plasma. These data demonstrate that the addition of an epitope tag had no effect on FVIII function or immunogenicity, and suggest that the BDD-E vector will be an effective reagent for non-human primate studies.

Behaviour and development of stunted and nonstunted Jamaican children

In order to examine the mechanism whereby stunted children have poor developmental levels, we compared the behaviour of stunted (N = 78) and nonstunted (N = 26) children aged 12 to 24 months, and examined the relationship of their behaviour to their developmental levels. The effect of nutritional supplementation with or without psychosocial stimulation on the stunted children's behaviour was also examined. The children were observed at home during 4 days over a period of 6 months. The stunted children showed significantly more apathy, and less enthusiasm and variety in exploring, were less happy and more fussy. Caretakers' vocalisations to them were less warm or instructive. Stunted children's activity level, exploratory and happy behaviours were predictive of change in developmental levels measured on the Griffiths Scales, from enrolment to 12 and 24 months later. Supplementation predicted mental age at 12 and 24 months after enrolment, however, it had no significant effect on behaviour.

Feeding-based arousal effects on visual recognition memory in early infancy

Arousal effects on a 1-trial visual recognition paired-comparison task were studied at newborn, 1-month, and 4-month test ages. Infants were tested before and after feeding, with arousal assumed to be lower after feeding. Newborns and 1-month-olds shifted from a familiarity preference before feeding to a novelty preference after feeding. A control group tested only after feeding confirmed that this shift was not due to increased stimulus exposure from the prefeeding test. By 4 months, infants showed novelty preferences independent of feeding. This age by arousal interaction for recognition memory extends previous knowledge by including endogenous arousal with age, stimulus, and length of exposure as contributors to familiarity-novelty preferences. It also extends and provides converging evidence for arousal effects on visual attention in early infancy found previously with preferential looking. A shift from subcortical to cortical dominance is supported.

Perinatal death: uncovering the needs of midwives and nurses and exploring helpful interventions in the United States, England, and Japan

Perinatal death is a crisis for midwives and nurses as well as for bereaved parents and extended families. Surveys and interviews conducted in the United States, England, and Japan described the needs and responses of nurses and midwives as they coped with their own feelings while caring for bereaved parents. Results emphasized common needs of caregivers for increased knowledge, mentored experience, communication skills, and personal support to confidently provide sensitive care to families. Although need for education regarding cultural-specific care was revealed, participants identified helpful strategies of care for bereaved parents that could extend and improve care universally.

Undernutrition and elevated blood lead levels: effects on psychomotor development among Jamaican children

OBJECTIVE

We examined whether or not the effect of elevated blood lead levels on children's psychomotor development was modified by their nutritional status.

DESIGN

Anthropometry, developmental quotients (DQs), blood lead levels and haemoglobin were measured in lead exposed and unexposed children with different levels of nutritional status. Social background and maternal height and verbal intelligence were also measured. Testers, anthropometrists and interviewers established reliabilities with a trainer before the study began.

SETTING

Children were from two suburban areas in Kingston, Jamaica. All measurements on the children were carried out at a research unit. Social background and maternal measurements were carried out at the children's homes.

SUBJECTS

The exposed group comprised 58 children (3-6 years) attending the same preschool which was situated in a lead contaminated environment. The unexposed group comprised 53 children attending a nearby preschool without lead contamination.

RESULTS

The exposed children had significantly higher blood lead levels and lower DQs, and their homes had poorer facilities than the unexposed children. The deficit in DQ was greater (10.6 points) among children with weight for height less than -1 SD (National Center for Health Statistics references) than among better nourished children (2 points).

CONCLUSIONS

Undernourished children exposed to lead may have more serious developmental deficits than better nourished children.

Folylpoly-gamma-glutamate carboxypeptidase from pig jejunum. Molecular characterization and relation to glutamate carboxypeptidase II

Jejunal folylpoly-gamma-glutamate carboxypeptidase hydrolyzes dietary folates prior to their intestinal absorption. The complete folylpoly-gamma-glutamate carboxypeptidase cDNA was isolated from a pig jejunal cDNA library using an amplified homologous probe incorporating primer sequences from prostate-specific membrane antigen, a protein capable of folate hydrolysis. The cDNA encodes a 751-amino acid polypeptide homologous to prostate-specific membrane antigen and rat brain N-acetylated alpha-linked acidic dipeptidase. PC3 transfectant membranes exhibited activities of folylpoly-gamma-carboxypeptidase and N-acetylated alpha-linked acidic dipeptidase, while immunoblots using monoclonal antibody to native folylpoly-gamma-glutamate carboxypeptidase identified a glycoprotein at 120 kDa and a polypeptide at 84 kDa. The kinetics of native folylpoly-gamma-carboxypeptidase were expressed in membranes of PC3 cells transfected with either pig folylpoly-gamma-carboxypeptidase or human prostate-specific membrane antigen. Folylpoly-gamma-carboxypeptidase transcripts were identified at 2.8 kilobase pairs in human and pig jejunum, human and rat brain, and human prostate cancer LNCaP cells. Thus, pig folylpoly-gamma-carboxypeptidase, rat N-acetylated alpha-linked acidic dipeptidase, and human prostate-specific membrane antigen appear to represent varied expressions of the same gene in different species and tissues. The discovery of the jejunal folylpoly-gamma-carboxypeptidase gene provides a framework for future studies on relationships among these proteins and on the molecular regulation of intestinal folate absorption.

Identification of a novel transcript produced by the gene responsible for the Hermansky-Pudlak syndrome in Puerto Rico

Hermansky-Pudlak Syndrome (HPS) is a rare, autosomal recessive disorder that is characterized by oculocutaneous albinism, a predisposition to mild bleeding caused by storage-pool deficient platelets, and a ceroid storage disorder. A gene responsible for HPS in Puerto Rico maps to chromosome 10q2 and isolation of the gene has been reported. We have now identified a variant HPS cDNA that contains the same 5' sequence as the published HPS gene and a unique 3' sequence. Analysis of genomic DNA suggests that the two cDNA are derived from alternative transcripts of a single gene; two polyadenylated transcripts were found in normal human melanocytes, human bone marrow cells, human melanoma cells, lymphoblastoid cell lines, and megakaryocytic leukemia cells by reverse transcriptase polymerase chain reaction and northern analysis. The splicing exhibited by this gene is identical to the splicing found to produce two alternative transcripts of the Chediak-Higashi Syndrome gene, another pigment disorder exhibiting platelet storage pool deficiency. These studies show that the HPS gene on chromosome 10 is complex and may have more than one biologically active transcript.

Aggressive behaviour in children and adolescents. Part I: A review of the effects of child and family characteristics

Interpersonal violence is a major public health concern throughout the West Indies, particularly in Jamaica. Many factors contribute to a youth's violent or aggressive behaviour, ranging from individual temperament, to family structure, to large sociocultural influences. In Part I, we review the incidence and severity of violence, and discuss the effects of individual characteristics, and of family structure and discipline. In Part II, the reported effects of school structure, peer relationships and interaction, corporal punishment and the media on violent behaviour in children and adolescents are reviewed, and potential policy implications are discussed.

The mouse pale ear (ep) mutation is the homologue of human Hermansky-Pudlak syndrome

The recessive mutation at the pale ear (ep) locus on mouse chromosome 19 was found to be the homologue of human Hermansky-Pudlak syndrome (HPS). A positional cloning strategy using yeast artificial chromosomes spanning the HPS locus was used to identify the HPS gene and its murine counterpart. These genes and their predicted proteins are highly conserved at the nucleotide and amino acid levels. Sequence analysis of the mutant ep gene revealed the insertion of an intracisternal A particle element in a protein-coding 3' exon. Here we demonstrate that mice with the ep mutation exhibit abnormalities similar to human HPS patients in melanosomes and platelet-dense granules. These results establish an animal model of HPS and will facilitate biochemical and molecular analyses of the functions of this protein in the membranes of specialized intracellular organelles.

Arousal-modulated attention at four months as a function of intrauterine cocaine exposure and central nervous system injury

CNS-compromised neonates are poor modulators tending to prefer less stimulation in all arousal conditions. Cocaine-exposed neonates also are poor modulators but tend to prefer more stimulation in all arousal conditions. Infants (N = 359, M = 4 months) were divided into 6 CNS injury groups and 1 cocaine-exposed, non-CNS-injured group and tested in three arousal conditions: less aroused (after feeding), more around-endogenous (before feeding), and more aroused-exogenous (after feeding with additional stimulation prior to each trial). Infants with CNS injuries still showed some degree of influence of arousal on attention that was now similar to that seen in normal neonates and 1-month-olds, while cocaine-exposed infants, 4-month-old normal and mild or moderate CNS-injury infants did not.

Complete short-term correction of canine hemophilia A by in vivo gene therapy

Hemophilia A is a severe bleeding disorder caused by a deficiency in clotting factor VIII (FVIII). A canine model that closely mimics the human disease was used to determine if an adenoviral vector expressing a human FVIII cDNA could be used to correct the hemophilia A phenotype. Within 48 hours after peripheral vein administration of the vector to FVIII-deficient dogs, the hemophilic phenotype was corrected, based on determination of the activated clotting time, the activated partial thromboplastin time, and the cuticle bleeding time. Direct measurement of human FVIII in the dog plasma showed FVIII expression at amounts well above the human therapeutic level. FVIII expression in treated dogs was short-term, lasting 1 to 2 weeks, due to the development of a human FVIII-specific inhibitor antibody response. These data provide the first demonstration of in vivo gene therapy of hemophilia A.

Prenatal cocaine exposure effects on arousal-modulated attention during the neonatal period

The organization of arousal and attention as a function of intrauterine cocaine exposure was investigated in 180 normal nursery infants prior to hospital discharge and at 1 month of age. This was done by studying visual looking preferences when infants were in three arousal conditions: less aroused (after feeding); more aroused-endogenous (before feeding); and more aroused-exogenous (after feeding but including 8-Hz visual stimulation prior to each visual preference trial). The stimuli were light panels illuminated at three temporal frequencies between 1 and 8 Hz presented in pairs using a balanced presentation series of trials. Infants not exposed to cocaine demonstrated strong arousal-modulated attention, preferring faster frequencies when less aroused and slower frequencies when more aroused in both endogenous and exogenous conditions. In contrast, cocaine-exposed infants showed a lack of arousal-modulated attention and preferred faster frequencies of stimulation regardless of arousal condition. Similar differences in arousal-modulated attention as a function of cocaine exposure were obtained at 1 month after birth, indicating that these effects lasted longer than would be reasonable to attribute to the active presence of cocaine or its metabolites. This form of stimulus-seeking behavior was shown to be independent of confounding factors associated with prenatal cocaine exposure such as the absence of prenatal care, alcohol use, minority status, or gender, as well as mediating factors associated with growth such as birthweight. A direct and more chronic effect of intrauterine cocaine exposure on arousal-modulated attention and presumably on the developing CNS therefore was supported.

Sustained expression of therapeutic levels of human factor VIII in mice

Deficiency of coagulation factor VIII (FVIII) results in hemophilia A, a common hereditary bleeding disorder. Using a human FVIII-encoding adenoviral vector, Av1ALAPH81, we have demonstrated expression of therapeutic levels of human FVIII in mice sustained for more than 5 months after vector administration. Administration of a high dose (4 x 10(9) plaque-forming units [pfu]) of Av1ALAPH81 to mice resulted in a peak expression of 2,063 ng/mL of human FVIII in the mouse plasma, with levels decreasing to background by weeks 15 to 17. Normal FVIII levels in humans range from 100 to 200 ng/mL and therapeutic levels are as low as 10 ng/mL. Alternatively, administration of 8- to 80-fold lower vector doses (5 x 10(8) pfu to 5 x 10(7) pfu) to normal adult mice resulted in expression of FVIII at therapeutic levels sustained for at least 22 weeks. Detailed analysis of vector toxicity indicated that the high vector dose caused a dramatic elevation of liver-specific enzyme levels, whereas an eight-fold lower vector dose was significantly less hepatotoxic. The data presented here demonstrate that administration of lower, less toxic vector doses allow long-term persistence of FVIII expression.

Transient immunosuppression permits successful repetitive intravenous administration of an adenovirus vector

The in vivo administration of adenovirus vectors frequently elicits a neutralizing antibody response which eliminates or substantially reduces the efficacy of subsequent treatments. Methods to overcome this significant barrier to repeat delivery will be required for the application of adenovirus-based gene therapy in the treatment of chronic disease. We have evaluated the relationship between the initial vector dose and the effectiveness of a second vector administration. C57BL/6 mice injected intravenously with up to 10(7) p.f.u. of a lacZ adenovirus vector, Av1lacZ4, expressed significant levels of human factor IX when injected with 2 x 10(8) p.f.u. of the factor IX vector, Av1H9F, 5 weeks later. An initial dose of 10(8) p.f.u. of Av1lacZ4 completely prevented expression of factor IX following the second administration due to the generation of neutralizing antibody. However, transient immunosuppression with deoxyspergualin (DSG) or cyclophosphamide at the time of initial exposure to 10(8) p.f.u. of Av1lacZ4 prevented the formation of anti-adenovirus neutralizing antibody and permitted an effective second administration of a factor IX vector. Furthermore, transient immunosuppression with cyclophosphamide concomitant with delivery of the factor IX vector enabled an effective administration of a third vector encoding human factor VIII. This approach, together with strategies to prolong the persistence of adenoviral vector expression, should permit long-term therapy with adenovirus-based vectors.

Slower economic growth affects the 1995 labor market

As the pace of economic activity moderated in 1995, job growth slowed. Nonetheless, it was enough to absorb the small increase in the supply of labor, with the result that the unemployment rate remained at about the same level it had reached at the end of 1994. In the first quarter of 1995, employment grew at a brisk pace but, as the economy began to slow, job gains fell sharply. Employment growth continued at a much more moderate pace for the balance of the year, so that, by the fourth quarter, nearly 1.9 million jobs had been added to the Nation's payrolls. By comparison, in the fourth quarter of 1994 alone, payroll employment had grown by 1.1 million. Most of the job gains in 1995 were in the services industry group. Manufacturing employment, which had been rising since the fall of 1993, began to decline in the spring, and by the end of 1995, that industry group had lost nearly a quarter of a million jobs. Employment increased in most of the other major industry groups, even though declines in some of their component industries partly offset gains in others.

Trichuris trichiura infection and cognitive function in Jamaican school children

Trichuris trichiura is extremely prevalent worldwide and there is concern that this geohelminth may affect the cognitive function of children in developing countries. A random-controlled, double-blind, treatment trial was conducted in Jamaican children with light to moderate infections. This was part of a research programme involving several studies in Jamaica. Ninety-seven subjects, each with a minimum of 1200 T. trichiura eggs/g faeces, were randomly assigned to placebo (N = 48) or treatment (N = 49) groups. Each pair of infected children was matched with an uninfected classmate (N = 48). All children were given seven cognitive function tests: French-learning; digit spans (forwards and backwards), Corsi block span; fluency; picture search; and silly sentences. Albendazole was given to the treatment group and the other groups received a placebo. Three months later, these treatments were repeated, and the cognitive function battery was given again. On pre-test, the infected groups performed significantly poorer only in the silly-sentence test (analysis of variance F-value = 8.17; two degrees of freedom; P < 0.001). There was no significant improvement with treatment in any of the tests. Taking into account these findings and those of the other Jamaican studies, it is therefore probable that light to moderate Trichuris infections have little effect on cognitive functioning in school children who have adequate nutritional status.

High-level tissue-specific expression of functional human factor VIII in mice

Hemophilia A results from subnormal levels of blood coagulation factor VIII (FVIII) and is an attractive target for gene therapy. However, progress has been impeded by features of FVIII biology such as low mRNA accumulation and the instability of the protein. We have shown previously that a FVIII adenoviral vector, Av1ALH81, allowed high-level expression of human FVIII in mice sustained for several weeks. Here, we have generated a second FVIII adenoviral vector, Av1ALAPH81, in which an intron was introduced into the FVIII expression cassette. Administration of Av1ALAPH81 to mice resulted in significantly increased FVIII plasma levels, 1,046 +/- 163 ng/ml compared to 307 +/- 93 ng/ml of FVIII detected in mice that received Av1ALH81. Normal FVIII levels in humans are 100-200 ng/ml and therapeutic levels are as low as 10 ng/ml. Therapeutic levels are defined as the amount of FVIII necessary to convert severe hemophilia to a moderate or mild hemophiliac condition. The increased potency of the second FVIII adenoviral vector allowed the administration of significantly lower, less toxic vector doses, while retaining the potential for high FVIII expression. Furthermore, we demonstrate that adenoviral-mediated expression of human FVIII can be limited to the liver by inclusion of a liver-specific promoter, thereby achieving the first step in regulated expression of human FVIII in vivo.

In vivo gene delivery and expression of physiological levels of functional human factor VIII in mice

Hemophilia A is caused by blood coagulation factor VIII (FVIII) deficiency and is an attractive target for gene therapy. However, features of FVIII physiology, such as the instability of the mRNA and protein, have provided obstacles to the design of a feasible strategy for the transfer and expression of the human FVIII gene in vivo. We have constructed a recombinant adenoviral vector, Av1ALH81, that contains the human FVIII cDNA from which the B-domain has been deleted (BDD FVIII) and extensively characterized this vector in vitro and in vivo. In vitro, HepG2, human hepatoma cells, transduced with Av1ALH81 secreted high levels of biologically active human BDD FVIII measured by the Coatest bioassay (> 2,400 mU per 10(6) cells per 24 hr). Administration of Av1ALH81 to mice, via tail vein, resulted in expression of human BDD FVIII in the mouse plasma at levels averaging 307 +/- 93 ng/ml 1 week post-injection, measured by a sensitive human FVIII-specific ELISA. Normal FVIII levels in humans are 100-200 ng/ml, and therapeutic levels are as low as 10 ng/ml. Purification of the human FVIII from the mouse plasma, and subsequent Coatest analysis, revealed that the human FVIII produced in the mice was biologically active. In addition, the duration of FVIII expression in vivo was followed, and high-level FVIII expression was sustained over a period of several weeks. The finding that an adenoviral vector can mediate high-level expression of human FVIII in an animal model provides the basis for the development of gene therapy for hemophilia A.

Identification of a melanosomal membrane protein encoded by the pink-eyed dilution (type II oculocutaneous albinism) gene

The pink-eyed dilution (p) locus in the mouse is critical to melanogenesis; mutations in the homologous locus in humans, P, are a cause of type II oculocutaneous albinism. Although a cDNA encoded by the p gene has recently been identified, nothing is known about the protein product of this gene. To characterize the protein encoded by the p gene, we performed immunoblot analysis of extracts of melanocytes cultured from wild-type mice with an antiserum from rabbits immunized with a peptide corresponding to amino acids 285-298 of the predicted protein product of the murine p gene. This antiserum recognized a 110-kDa protein. The protein was absent from extracts of melanocytes cultured from mice with two mutations (pcp and p) in which transcripts of the p gene are absent or greatly reduced. Introduction of the cDNA for the p gene into pcp melanocytes by electroporation resulted in expression of the 3.3-kb mRNA and the 110-kDa protein. Upon subcellular fractionation of cultured melanocytes, the 110-kDa protein was found to be present in melanosomes but absent from the vesicular fraction; phase separation performed with the nonionic detergent Triton X-114 confirmed the predicted hydrophobic nature of the protein. These results demonstrate that the p gene encodes a 110-kDa integral melanosomal membrane protein and establish a framework by which mutations at this locus, which diminish pigmentation, can be analyzed at the cellular and biochemical levels.

The mouse pink-eyed dilution gene: association with hypopigmentation in Prader-Willi and Angelman syndromes and with human OCA2

Mutations at the mouse pink-eyed dilution locus, p, cause hypopigmentation. We have cloned the mouse p gene cDNA and the cDNA of its human counterpart, P. The region of mouse chromosome 7 containing the p locus is syntenic with human chromosome 15q11-q13, a region associated with Prader-Willi syndrome (PWS) and Angelman syndrome (AS), both of which involve profound imprinting effects. PWS patients lack sequences of paternal origin from 15q, whereas AS patients lack a maternal copy of an essential region from 15q. However, the critical regions for these syndromes are much smaller than the chromosomal region commonly deleted that often includes the P gene. Hypopigmentation in PWS and AS patients is correlated with deletions of one copy of the human P gene that is highly homologous with its mouse counterpart. A subset of PWS and AS patients also have OCA2. These patients lack one copy of the P gene in the context of a PWS or AS deletion, with a mutation in the remaining chromosomal homologue of the P gene. Mutations in both homologues of the P gene of OCA2 patients who do not have PWS or AS have also been detected.

Weaning-food viscosity and energy density: their effects on ad libitum consumption and energy intakes in Jamaican children

The effects of weaning-food viscosity and energy density on consumption and energy intake were determined in 15 non-breast-fed Jamaican children aged 7-15 mo under standardized conditions. We tested whether feeding thick, energy-dense porridge four times daily resulted in increased energy intakes and whether amylase treatment to reduce viscosity offered any advantage. When a traditional liquid, low-density porridge (2.15 kJ/g) was fed, the mean (+/- SD) daily consumption was 139 +/- 25 g/kg and the mean daily energy intake was 296 +/- 54 kJ/kg. When a semisolid high-density porridge (4.09 kJ/g) was fed, consumption was significantly lower (98 +/- 21 g/kg) but the daily energy intake was significantly higher--402 +/- 85 kJ/kg (P < 0.001). Amylase treatment of the thick energy-dense porridge did not increase intakes further. Meal duration for the thick porridge (12.9 +/- 4.0 min) was significantly longer than that for the low-density (7.4 +/- 2.6 min) or amylase-treated (6.4 +/- 1.8 min) porridges.

Implementation of a provider credentialing/recredentialing process and development of a physician profile in an IPA-model HMO

The process of credentialing and recredentialing providers in health plans is time-consuming and universally hated by doctors, but it is essential to maintaining the quality of the health care plan. It also can yield information about the quality of service provided in general by the network of physicians, as one IPA-model plan discovered.

African origin of an intragenic deletion of the human P gene in tyrosinase positive oculocutaneous albinism

Oculocutaneous albinism (OCA) is a genetically heterogeneous hypopigmentation disorder. One of the two major autosomal recessive forms involves the tyrosinase gene (OCA1), while the other form (OCA2) has recently been associated with alterations of the P gene on chromosome 15. OCA2 is about twice as common as OCA1 in African and African-American populations. We now describe an interstitial deletion that removes a single exon of the P gene. In a large family from an inbred population of tri-racial origin, all individuals with OCA2 were found to be homozygous for this allele. Moreover, the same mutant P allele was detected in several unrelated African American individuals with OCA2, but not in Caucasians with OCA2. The detection of the same allele in two unrelated Africans with OCA2 indicates an African origin for this allele.

A cluster of three GABAA receptor subunit genes is deleted in a neurological mutant of the mouse p locus

The mouse pink-eyed cleft-palate (p(cp)) mutation is characterized by hypopigmentation associated with cleft palate, neurological disorders and runting. Most p(cp) homozygotes are born with cleft palate and die shortly after birth, presumably as a result of feeding problems. A few exceptional p(cp) mutants live beyond this stage but display tremor and jerky gait. We report here that the genes encoding the gamma-aminobutyric acid type A (GABAA) receptor subunits alpha 5 (originally described as alpha 4; ref. 4), beta 3 and gamma 3 are disrupted by a deletion in p(cp) mice. We also show that the alpha 5 and gamma 3 genes are located between the p and beta 3 genes on mouse chromosome 7. The p(cp) deletion leads to alterations of binding properties of the GABAA receptors in the brain, providing an in vivo model system for studying GABAA receptor function. The human homologue of the region deleted in p(cp) mice is associated with Angelman syndrome. Thus, p(cp) mice may be useful in defining the region containing the gene(s) for this syndrome.

Mitochondrial Ca2+ uptake at submicromolar [Ca2+]i in permeabilised pancreatic acinar cells

We studied the uptake of Ca2+ in different intracellular Ca2+ pools by use of steady-state measurement of 45Ca2+ in a preparation of digitonin-permeabilized pancreatic acinar cells. The Ca2+ content of all intracellular pools was assessed at different free Ca2+ concentrations between 0.1 and 1 microM. At low Ca2+ concentrations, almost 50% of Ca2+ was taken up, ATP-dependent, in a non-mitochondrial pool. Even at 0.1 microM free Ca2+ the mitochondrial Ca2+ pool contained 26% (3.4 +/- 0.8 nmol Ca2+/mg prot) of the total Ca2+ and this percentage was increased to 49% at 1 microM Ca2+ (16.7 +/- 1.1 nmol Ca2+/mg prot). Our data also show that the uptake into the non-mitochondrial pool can be further differentiated on the basis of ATP-dependence, and that the ATP-independent uptake has a biphasic dependency on the free Ca2+ concentration.

High-frequency genetic reversion mediated by a DNA duplication: the mouse pink-eyed unstable mutation

The mouse pink-eyed unstable (p(un)) mutation, affecting coat color, exhibits one of the highest reported reversion frequencies of any mammalian mutation and is associated with a duplication of genomic DNA at the p locus. In this study, genomic clones containing the boundaries of the p(un) duplication were isolated and characterized. The structure of these sequences and their wild-type and revertant counterparts were analyzed by restriction mapping, PCR product analysis, DNA sequence analysis, and pulsed-field gel electrophoresis. DNA from p(un) was distinguished from wild-type and revertant DNA by a head-to-tail tandem duplication of approximately 70 kilobases. No differences were detected between revertant and wild-type DNAs. Thus, the reversion in phenotype of p(un) mice is coupled with the loss of one copy of an approximately 70-kilobase duplicated segment. Testable models are presented to account for p(un) reversion.