Evaluating the impact of CPAP weaning procedures on total days on nasal CPAP: A retrospective chart review.

BACKGROUND: There is no consensus on how to wean infants from Nasal Continuous Positive Airway Pressure (NCPAP). We hypothesized that ceasing NCPAP abruptly would decrease the duration required, compared with a gradual wean. METHODS: This retrospective chart review included preterm infants requiring NCPAP for over 48 hours. Cohort1 weaned NCPAP by cycling on and off, while cohort 2 ceased NCPAP abruptly. The primary outcome was total days on NCPAP. Secondary outcomes included rate of bronchopulmonary dysplasia, weight gain, duration of hospital stay, and compliance with the use of stability criteria. RESULTS: 81 infants met inclusion criteria in cohort one, and 89 in cohort two. Median days on NCPAP were 17.0 and 11.0 days, respectively, not significant. There was no significant difference in secondary outcomes. CONCLUSIONS: There was no significant association between the two NCPAP weaning protocols and the outcomes studied.

Worsening anemia associated with volvulus in a stable neonate with intestinal obstruction.

Intrauterine intestinal obstruction complicated by midgut volvulus is a serious life-threatening diagnosis. Immediate surgical intervention is generally the course of action upon diagnosis to prevent morbidity and mortality. We report a case of intrauterine intestinal obstruction where the neonate then presented with an unusual onset of volvulus within the first 12 hours of life. The patient was born with generalized edema, a distended abdomen, and pallor. Unlike many cases, the patient did not present with typical signs of volvulus. Diagnostic imaging preceding delivery and the stable postnatal clinical course did not offer a justification for immediate laparotomy. Less than 24 hours later, the patient's hemoglobin significantly dropped leading to an emergent laparotomy. Findings included a volvulus of the terminal ileum and large amounts of intraluminal blood. Our case report includes an analysis of clinical observations that should be considered so that patients presenting with similar signs receive earlier surgical intervention.

Field testing of decision coaching with a decision aid for parents facing extreme prematurity.

OBJECTIVE: The objective of this study is to assess and modify an existing decision aid and field-test decision coaching with the modified aid during consultations with parents facing potential delivery at 23 to 24 weeks gestation. STUDY DESIGN: International Patient Decision Aid Standards instrument (IPDASi) scoring deficits, multi-stakeholder group feedback and α-testing guided modifications. Feasibility/acceptability were assessed. The Decisional Conflict Scale was used to measure participants' decisional conflict before (T1) and immediately after (T2) the consultation. RESULTS: IPDASi assessment of the existing aid (score 11/35) indicated it required updated data, more information and a palliative care description. Following modification, IPDASi score increased to 26/35. Twenty subjects (12 pregnancies) participated in field-testing; 15 completed all questionnaires. Most participants (89%) would definitely recommend this form of consultation. Decisional conflict scores decreased (P<0.001) between T1 (52±25) and T2 (10±16). CONCLUSION: Field testing demonstrated that consultations using the aid with decision coaching were feasible, reduced decisional conflict and may facilitate shared decision-making.

Shared decision making for infants born at the threshold of viability: a prognosis-based guideline.

OBJECTIVE: Making prenatal decisions regarding resuscitation of extremely premature infants, based on gestational age alone is inadequate. We developed a prognosis-based guideline. STUDY DESIGN: We followed a five step approach and used the AGREE II framework: (1) systematic review and critical appraisal of published guidelines; (2) identification of key medical factors for decision making; (3) systematic reviews; (4) creation of a multi-disciplinary working group and (5) external consultation and appraisal. RESULT: No published guideline met high-quality appraisal criteria. Survival, neurodevelopmental disability, quality of life of child and parents, and maternal mortality and risk of long-term morbidity were identified as key for quality decision-making. Eighteen stakeholders (including parents) advocated for the incorporation of parents' values and preferences in the process. CONCLUSION: A novel framework, based on prognosis, was generated to guide when early intensive and palliative care may both be offered to expectant parents. Pre-implementation assessment is underway to identify barriers and facilitators to putting in practice.

Chitotriosidase and gene therapy for fungal infections.

Chitotriosidase secreted by activated human macrophages has been implicated in the defence against chitin-bearing pathogens. The antifungal properties of human chitotriosidase were investigated here following retroviral vector-mediated gene transfer of the open reading frame of the chitotriosidase gene into Chinese hamster ovary cells. A chitinase assay confirmed that the engineered cells secreted recombinant chitotriosidase constitutively. Two dimensional gel electrophoresis and western blotting indicated that the recombinant protein is the major, chitin-binding, fifty kilodalton isoform. Culture medium conditioned by the transduced cells inhibited growth of isolates of Aspergillus niger, Candida albicans and Cryptococcus neoformans. Furthermore, longevity was significantly increased in a mouse model of cryptococcosis when cells transduced with the chitotriosidase gene and encapsulated in alginate microspheres were implanted subcutaneously in the animals. Engraftment of microcapsules containing cells transduced with the chitotriosidase gene has the potential to combat infections caused by chitinous pathogens through the prolonged delivery of recombinant chitotriosidase.

Parathyroid hormone-related peptide modulates signal pathways in skin and hair follicle cells.

Parathyroid hormone-related protein (PTHrP) is secreted by skin epithelial cells and is thought to play an important role in the development and function of the hair follicle. It was hypothesized that PTHrP binds to receptors in dermal papilla cells and modulates intracellular signaling systems in these cells. We tested the effects of PTHrP on protein synthesis, protein kinase A (PKA) and protein kinase C (PKC) activities as well as tyrosine phosphorylation in rat vibrissa dermal papilla and capsular fibroblast cells. Cells were cultured in the presence or absence of the N-terminal peptide PTHrP1-34 for 48 h and detergent extracts prepared. Proteins were separated by electrophoresis. Phosphotyrosine and the PTH/PTHrP receptor immunoreactivity was identified by Western blot analysis. PKC and PKA activities in the cells were measured using colorimetric enzyme assays. Extracts of both dermal papilla cells and capsular fibroblasts displayed immunoreactivity to the PTH/PTHrP receptor. Electrophoresis showed that PTHrP treatment reduced the density of a 50-kDa protein in dermal papilla cells but not in capsular fibroblasts. Media conditioned by the cells showed similar changes, indicating that the PTHrP-modulated 50-kDa protein was secreted. Furthermore, 2-D gel electrophoresis indicated that the protein had a number of phosphorylation sites. Western analysis with antiphosphotyrosine antibodies confirmed a significant decrease in the intensity of a phosphorylated 50-kDa protein in papilla cells and papilla cell-conditioned medium. PKC and PKA activities of papilla cells were unaffected by PTHrP. However, activities of PKC were increased and PKA reduced in capsular fibroblasts following peptide treatment. These cell-specific effects showed that endogenous PTHrP may activate different intracellular pathways in mesenchymal cells of skin and elicit changes in levels of locally secreted proteins that specifically modulate normal follicular function.

Tyr-TGFalpha transgenic mice develop ocular melanocytic lesions.

Transforming growth factor-alpha (TGFalpha) has been implicated in melanocyte transformation, as it is expressed in melanocytic lesions and in melanoma cells. We investigated its role in melanoma development using a transgenic mouse model. The mice were generated by microinjection of a transgene with 270 bp of the mouse tyrosinase promoter and the cDNA for human TGFalpha. No significant skin abnormalities were found, but individuals from three transgenic lines developed ocular melanocytoses (seven out of 10 transgenics), usually after a long latency period. In particular, the melanocyte component of the choroid was thicker than in non-transgenic controls, consistent with hyperplasia. The retinal pigment epithelium was unaffected. Melanocytic lesions were also present in the posterior eye, and abnormal distributions of melanocytes were found in neural tissue of the brain, skeletal muscle of the head and the Harderian glands, indicating migration from the choroid. It was concluded that mice engineered to express the normal growth factor TGFalpha from a tyrosinase promoter spontaneously developed melanocytic lesions in the eye but not the skin.

Extracellular matrix molecules and follicle morphogenesis in ovine skin.

Chondroitin sulphate, fibronectin, laminin and the hyaluronan receptor, CD44, were localized in ovine skin during follicle morphogenesis. Prior to initiation, chondroitin sulphate was detected in the mesenchyme adjacent to the dermal-epidermal junction and showed an approximately regular periodicity in staining intensity. With the appearance of follicle primordia, the more strongly stained regions of the matrix were associated with mesenchymal condensations. During later development and in the mature follicle, staining was localized to the matrices of cells of the dermal sheath and papilla. CD44 was also localized in the mesenchymal condensations at follicle initiation and, subsequently, in the dermal sheath. Fibronectin staining was confined to the mesenchyme prior to follicle formation and became associated with presumptive papilla and dermal sheath cells during follicle formation and maturation. Fibronectin antisera detected an approximately 220 kDa protein in western blots of adult and fetal skin. An additional band of 150 kDa was also observed prior to follicle initiation. In contrast, laminin was predominantly restricted to the basal laminae of developing and mature follicles. The aggregative behaviour of ovine papilla cells was examined in vitro. The number and size of aggregates were not affected by inclusion of chondroitin sulphate or fibronectin in the culture medium, but both increased in the presence of hyaluronidase. Chondroitinase had the opposite effect and beta-D-xyloside completely abolished aggregative behaviour. In conclusion, the appearance of certain matrix molecules may presage morphogenetic movements of cells at follicle initiation and regulate patterns of follicle distribution in skin during fetal life.

Regulation of epidermal growth factor receptor expression in human melanocytes.

The epidermal growth factor receptor (EGFR) and its ligand, transforming growth factor alpha (TGFalpha), are reportedly involved in autocrine growth of melanoma cells. The signal pathway has also been implicated in early events of transformation, suggesting a function for EGFR in normal cells. This study reports the presence of EGFR in cultured melanocytes and examines some cellular responses to TGFalpha. Western analysis revealed 170 kDa bands in extracts of cultured neonatal human melanocytes, corresponding to the receptor Mr. Protein expression was more pronounced in cells during active growth. EGFR were less evident in cultures populated predominantly by melanized cells, indicating that receptor expression became reduced in differentiating cells. Immunocytochemistry confirmed these observations and also showed that EGFR reactivity was predominantly localized in the cell body but absent from dendrites. Addition of TGFalpha to early cultures induced a rapid increase in phosphotyrosine signal of the 170 kDa protein. Longer treatment (24-48 h) increased the intensity of the EGFR signal, suggesting that receptors had been upregulated. However, inclusion of TGFalpha in cultures did not result in an increase in cell numbers when compared to controls. The observations provide evidence of the existence of a receptor-mediated pathway in melanocytes which has transforming potential in vivo.

Ethics seminars: the practice of medical procedures on newly dead patients--is consent warranted?

The use of the newly dead to teach procedures is widely practiced in training institutions. This model allows a realistic opportunity both to become more familiar with lifesaving maneuvers before they are actually necessary and to maintain proficiency. Whether to notify the next of kin first has been an issue of ethical debate. Some argue a "don't ask, don't tell" policy is justified, while others mandate open consent by family members prior to the practice. Several medical studies have found that patients and families are likely to consent to the procedures but prefer to be asked permission first. Multiple legal cases have addressed the issue of usage of cadavers postmortem without expressed permission. Earlier cases emphasized the concept of "pseudo-property" rights and declared that the next of kin do not have constitutional ownership of the deceased person's body. More recent legal cases are declaring that families do, in fact, possess these rights. In this day and age of increasing recognition of personal autonomy, it is probably prudent to approach the next of kin for permission before performing procedures on the newly deceased.

Concurrent Parkinson tremors.

1. Concurrent resting and postural tremors of patients with idiopathic Parkinson's disease were monitored using transducers responding to angular velocity of rotation. Spectra and correlation functions were calculated for each pair of records. 2. When concurrent tremor spectra share indistinguishable fundamental frequencies, have statistically significant peaks in their coherence spectra at those fundamental frequencies, and show significant peaks in their cross-correlation functions near zero delay, they are classified as linearly dependent. When such tremor records are superimposed, their phase-locked behaviour is evident. 3. Pairs of correlated concurrent tremors, of varying duration, have been observed in both hands, both feet and in either hand and the contralateral or ipsilateral foot. Correlated tremors may be concurrent with other tremors that are independent. We hypothesize that correlated Parkinson tremors arise from one or more common (and possibly unilateral) central sources.

Expression of nerve growth factor mRNA and its translation products in the anagen hair follicle.

The cellular localization of NGF mRNA and its translation products have been identified in ovine hair follicles. NGF mRNA was detected in the proliferating cells of the follicle bulb and differentiating cells of the suprabulbar region, but was absent from the outer root sheath. Western analysis revealed the presence of a 73 kDa NGF prohormone in extracts of ovine flank skin, but the mature 13 kDa NGF was absent. Immunohistochemical analysis with antibodies specific to mouse NGF and a pro-NGF specific domain localized the NGF prohormone to outer root sheath cells in the upper bulb region of the follicle, adjacent to the zone of keratinization. Antibody binding was also associated with the luminal epithelium of the apocrine sweat gland and the pilary canal of the follicle at its junction with the epidermis. These observations, together with the reported presence of high- and low-affinity NGF receptors in the follicle, implicate the NGF prohormone-responsive neuronal system in the regulation of hair growth.

Commercial recombinant human beta-nerve growth factor and adult rat dorsal root ganglia contain an identical molecular species of nerve growth factor prohormone.

Examination of commercial recombinant human beta-nerve growth factor (rh-beta-NGF) preparations with polyclonal antibodies specific to 13-kDa NGF and pro-NGF-specific domains revealed the presence of high-molecular-mass immunoreactive proteins, including a 60-kDa NGF prohormone. On incubation with a mixture of N- and O-specific glycosidases, the 60-kDa NGF pro-hormone generated a 32-kDa protein corresponding to the molecular size of NGF precursor predicted by the cloned human NGF cDNA. Highly sensitive chemiluminescence immunoblot analysis of adult rat dorsal root ganglia, spinal cord, and colon tissues with NGF- and pro-NGF domain-specific antibodies also revealed the presence of high-molecular-mass proteins, including the 60-kDa NGF prohormone. Based on the presence of the 60-kDa NGF prohormone in dorsal root ganglia and its efferent tissues, we suggest that proteolytically unprocessed, glycosylated NGF prohormone may mediate interactions between neurons and the tissues they innervate.

Quantitative digitography (QDG): a sensitive measure of digital motor control in idiopathic Parkinson's disease.

This study introduces a new method for studying, quantitatively, the dynamics of finger movement using data obtained from sequences of key strikes on a computer-interfaced piano keyboard. We have called this quantitative digitography (QDG). This initial article introduces the method in a group of patients with Parkinson's disease and in a group of healthy subjects using simple, repetitive, alternating finger-tapping for 60 seconds. Patients with idiopathic Parkinson's disease (IPD) were studied "ON" and "OFF" dopaminergic medication before and after pallidotomy. Customized software allowed the independent analysis of key strike velocity, duration of key strike, and frequency of tapping along with a quantitative measure of the regularity of performance. Quantitative measures of the improvement in performance after medication are presented for each parameter of movement. The technique also reveals correlates of some clinical phenomena of the temporal disturbances of repetitive motion in IPD, such as fatigue, tremor, freezing, and festination. We demonstrate that the performance of 60 seconds of alternating finger tapping on a computerized keyboard yields objective measures of motor performance that are significantly different in patients with IPD "OFF" when compared with "ON" medication and when compared with healthy subjects. This is the first time that such a method has been used in the measurement of specific kinematics of digital motion in Parkinson's disease. The equipment is inexpensive and portable and the data are rapidly and easily collected, making it suitable for the outpatient setting.

Cultivation of epithelia from the secretory coil of the ovine apocrine gland: evidence of secretory cell function and ductal morphogenesis in vitro.

The secretory coil of the ovine apocrine gland is composed predominantly of two cell types, secretory cells lining the lumen and myoepithelial cells adjacent to the basement membrane. The glands synthesize a number of hormones and growth factors, but analysis of the functions of these molecules may be hampered by the mixing of apocrine and sebaceous secretions in the pilary canal. The purpose of this study was to isolate the glands and devise simple culture procedures to facilitate investigations of secretory cell function. The most successful approach involved microdissection of the secretory coils individually from skin biopsies and culture in Dulbecco's modified Eagle's medium. After 1-2 wk in medium, cell outgrowths were seen from explants. These consisted predominantly of populations of epithelial cells, many containing granules. Smaller granules were usually concentrated around the cell nuclei and accumulated lipophilic dyes. Large granules were unreactive. Western analysis showed that cells in culture synthesized nerve growth factor-like peptides, a feature consistent with one of the functions of the gland in vivo. When isolated secretor, coils were explanted to culture dishes coated with matrigel, highly compact, multilayered masses of cells grew out. Subsequently, tubular structures formed. The observations suggest that some differentiated functions of gland cells were retained in vitro and that the procedures described provide a system for the study, of apocrine secretions in isolation from those of other skin glands.

Do parents want to be present during invasive procedures performed on their children in the emergency department? A survey of 400 parents.

STUDY OBJECTIVES: No large study has addressed whether parents want to be present when invasive procedures are performed on their children in the emergency department. We conducted a survey to address this question. METHODS: The study used a self-administered, written survey consisting of 5 pediatric scenarios with increasing level of procedural invasiveness. Parents in an urban, teaching hospital ED waiting area were asked to participate. RESULTS: Of 407 persons asked to participate, 400 (98%) completed the survey. The number of parents expressing a desire to be present during a procedure performed on their child was 387 (97.5%) for venipuncture of the extremity, 375 (94.0%) for laceration repair, 341 (86.5%) for lumbar puncture, and 317 (80.9%) for endotracheal intubation. For a major resuscitation scenario, 316 (80.7%) wished to be present if their child were conscious during the resuscitation, 277 (71.4%) wanted to be present if their child were unconscious during the resuscitation, whereas 322 (83.4%) indicated a desire to be present if their child were likely to die during the resuscitation. Of the 400, 261 (65.3%) wished to be present for all 5 scenarios. Only 26 (6.5%) wanted the physician to determine parental presence in all 5 scenarios. CONCLUSION: Most parents surveyed would want to be present when invasive procedures are performed on their children. With increasing procedural invasiveness, parental desire to be present decreased. However, most parents would want to be in attendance if their child were likely to die, and nearly all parents want to participate in the decision about their presence.

Interactions between epidermal growth factor and the Tabby mutation in skin.

Mutations of the X-linked genes Tabby (Ta) in mice and EDA in humans result in developmental and functional abnormalities, primarily in the skin and hair follicles. Although both genes are believed to encode membrane-associated proteins, it has been suggested that, in the mouse, the mutation is linked to a deficiency of epidermal growth factor (EGF). This study investigated relationships between the skin abnormalities of Ta mice and the EGF signal pathway. The distribution of endogenous EGF in tissues of Ta/Y and +/Y animals was examined and, because of its reported morphogenetic actions and ability to overcome receptor signalling defects in vivo, the effects of exogenous EGF on the hair follicle population were determined. EGF levels were similar in a number of tissues of Ta/Y and +/Y mice, but amounts in Ta/Y submaxillary glands were reduced, probably due to a smaller gland size. Exogenous EGF inhibited hair follicle development and decreased follicle density in both genotypes. It was concluded from comparisons of the distributions of EGF and its effects in skin with those in mice bearing mutations in the EGF signal pathway that the normal phenotype results from interactions between EGF and the Ta peptide in skin.