Infrared and Raman screening of seized novel psychoactive substances: a large scale study of >200 samples.

The potential of IR absorption and Raman spectroscopy for rapid identification of novel psychoactive substances (NPS) has been tested using a set of 221 unsorted seized samples suspected of containing NPS. Both IR and Raman spectra showed large variation between the different sub-classifications of NPS and smaller, but still distinguishable, differences between closely related compounds within the same class. In initial tests, screening the samples using spectral searching against a limited reference library allowed only 41% of the samples to be fully identified. The limiting factor in the identification was the large number of active compounds in the seized samples for which no reference vibrational data were available in the libraries rather than poor spectral quality. Therefore, when 33 of these compounds were independently identified by NMR and mass spectrometry and their spectra used to extend the libraries, the percentage of samples identified by IR and Raman screening alone increased to 76%, with only 7% of samples having no identifiable constituents. This study, which is the largest of its type ever carried out, therefore demonstrates that this approach of detecting non-matching samples and then identifying them using standard analytical methods has considerable potential in NPS screening since it allows rapid identification of the constituents of the majority of street quality samples. Only one complete feedback cycle was carried out in this study but there is clearly the potential to carry out continuous identification/updating when this system is used in operational settings.

Tyrosine phosphorylation of BCR by FPS/FES protein-tyrosine kinases induces association of BCR with GRB-2/SOS.

The human bcr gene encodes a protein with serine/threonine kinase activity, CDC24/dbl homology, a GAP domain, and an SH2-binding region. However, the precise physiological functions of BCR are unknown. Coexpression of BCR with the cytoplasmic protein-tyrosine kinase encoded by the c-fes proto-oncogene in Sf-9 cells resulted in stable BCR-FES protein complex formation and tyrosine phosphorylation of BCR. Association involves the SH2 domain of FES and a novel binding domain localized to the first 347 amino acids of the FES N-terminal region. Deletion of the homologous N-terminal BCR-binding domain from v-fps, a fes-related transforming oncogene, abolished transforming activity and tyrosine phosphorylation of BCR in vivo. Tyrosine phosphorylation of BCR in v-fps-transformed cells induced its association with GRB-2/SOS, the RAS guanine nucleotide exchange factor complex. These data provide evidence that BCR couples the cytoplasmic protein-tyrosine kinase and RAS signaling pathways.

Surface-enhanced Raman spectroscopy of novel psychoactive substances using polymer-stabilized Ag nanoparticle aggregates.

A set of seized "legal high" samples and pure novel psychoactive substances have been examined by surface-enhanced Raman spectroscopy using polymer-stabilized Ag nanoparticle (Poly-SERS) films. The films both quenched fluorescence in bulk samples and allowed identification of µg quantities of drugs collected with wet swabs from contaminated surfaces.

Regulation of the human c-fes protein tyrosine kinase (p93c-fes) by its src homology 2 domain and major autophosphorylation site (Tyr-713).

The c-fes proto-oncogene product is expressed predominantly in hematopoietic cells of the myeloid lineage and has been implicated in the regulation of myeloid differentiation. The c-fes locus encodes a 93-kDa protein tyrosine kinase (p93c-fes) that possesses several structural features characteristic of the cytoplasmic class of protein tyrosine kinases, including a consensus sequence for autophosphorylation surrounding Tyr-713 and a src homology 2 (SH2) domain. To assess the effect of each of these potential regulatory sites on p93c-fes protein tyrosine kinase activity, we specifically deleted the c-fes SH2 domain using the polymerase chain reaction and replaced Tyr-713 with phenylalanine by oligonucleotide-directed mutagenesis (Y713F mutant). The resulting mutants were expressed in Escherichia coli and assayed for changes in protein tyrosine kinase activity using an immune complex kinase assay. Both mutations produced a marked decrease in the rate and extent of autophosphorylation and phosphorylation of the model substrate, enolase. To test whether the c-fes SH2 domain could interact with the autophosphorylated kinase domain, the SH2 domain was expressed as a fusion protein with glutathione S-transferase and immobilized on glutathione-agarose. The recombinant c-fes SH2 domain precipitated p93c-fes as readily as a monoclonal antibody. Binding of the SH2 domain to p93c-fes was completely dependent upon autophosphorylation, as a kinase-defective mutant of p93c-fes was not precipitated by the SH2 domain. High-affinity binding was also observed with recombinant SH2 domains from v-src and v-fps, raising the possibility of protein-protein interactions between various members of the cytoplasmic PTK family. These results indicate that the c-fes SH2 domain and consensus autophosphorylation site (Tyr-713) play major roles in the positive regulation of p93c-fes tyrosine kinase activity, possibly through intramolecular interaction.

Tyrosine phosphorylation enhances the SH2 domain-binding activity of Bcr and inhibits Bcr interaction with 14-3-3 proteins.

The cellular Bcr protein consists of an N-terminal serine/threonine kinase domain, a central guanine nucleotide exchange factor homology region and a C-terminal GTPase-activating protein domain. Previous work in our laboratory established that Bcr is a major transformation-related substrate for the v-Fps tyrosine kinase, and tyrosine phosphorylation of Bcr induces Bcr-Grb-2/SOS association in vivo through the Src homology 2 (SH2) domain of Grb-2. In the present study, we mapped the region of Bcr tyrosine phosphorylation by c-Fes, the human homologue of v-Fps, to Bcr N-terminal amino acids 162-413 by using a baculovirus/Sf-9 cell co-expression system. Tyrosine phosphorylation of Bcr by Fes greatly enhanced the binding of Bcr to the SH2 domains of multiple signalling molecules in vitro, including Grb-2, Ras GTPase activating protein, phospholipase C-gamma, the 85,000 M(r) subunit of phosphatidylinositol 3'-kinase, and the Abl tyrosine kinase. In contrast with SH2 binding, tyrosine phosphorylation of Bcr reduced its ability to associate with the 14-3-3 protein Bap-1 (Bcr-associated protein-1), a Bcr substrate and member of a family of phosphoserine-binding adaptor proteins. These experiments provide in vitro evidence that tyrosine phosphorylation may modulate the interaction of Bcr with multiple growth-regulatory signalling pathways.

Vitamin E and necrotizing enterocolitis.

Although vitamin E has been shown to reduce the incidence of severe sequelae from retrolental fibroplasia, there have been recent suggestions that its use may be associated with an increased incidence of necrotizing enterocolitis (NEC). A review was made of experience with vitamin E, both intramuscular and oral, and NEC over a 4 1/2-year period. Of 418 infants of birth weight less than 1,500 g admitted during this period, 28/209 infants who had received vitamin E had definite NEC (13.4%) compared with 12/209 who had not received vitamin E (5.74%, chi 2 = 7.07, P = .008). For infants of birth weight less than 1,250 g, 16/103 infants who received vitamin E developed NEC v 1/159 who had not (chi 2 = 21.1, P less than .001); the incidence of NEC was not significantly different between the two groups for infants with birth weight between 1,250 to 1,500 g. The early mortality (less than seven days) for infants with birth weight of 1,500 g or less was significantly greater for those who had not received vitamin E (43.5% v 13.8%, chi 2 = 44.9, P less than .001), most probably a reflection of the omission of this drug for the most critically ill infants in this retrospective review. The incidence of NEC was not different for infants with birth weight of 1,500 g or less who received intramuscular vitamin E compared with control infants from the same period. For those infants for whom serum tocopherol levels were available, no infant who developed NEC and who had received only oral vitamin E had a serum tocopherol levels of greater than 3.5 mg/100 mL.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of alterations of inspiratory and expiratory pressures and inspiratory/expiratory ratios on mean airway pressure, blood gases, and intracranial pressure.

Twenty neonates requiring mechanical ventilation for respiratory failure, including 13 with hyaline membrane disease, were studied to assess the effects of alterations in ventilator settings on mean airway pressure (MAP), blood gases, and intracranial pressure (ICP). The study involved random alterations in peak inspiratory pressure (PIP), positive end-expiratory pressure (PEEP), and inspiratory/expiratory ratio while MAP, PaO2, ICP, and end-tibal PCO2 were continuously monitored. The results showed a significant relationship between MAP and PaO2 that was expressed as the change in PaO2 per millimeter of mercury change in MAP (delta PaO2/delta MAP) with a mean delta PaO2/delta MAP of 4.92. The delta PaO2/delta MAP was highest for changes in PEEP (6.08), followed by PIP (5.07), and inspiratory/expiratory ratio (1.9). There was a significant relationship between alterations in PEEP and PIP vs PaCO2 and pH. Increases in PEEP and decreases in PIP resulted in an elevated PaCO2 and a lowered pH, and decreases in PEEP and increases in PIP resulted in a decreased PaCO2 and an elevated pH. There was no significant relationship between MAP and ICP, but there was a significant association between delta ICP and delta PaCO2 during alterations in PIP (r = .64, P less than .001). Increases in PEEP will lead to the greatest increase in PaO2 per change in MAP, followed by increase in PIP and inspiratory/expiratory ratio using a pressure-limited ventilator.

Limitations of self-inflating resuscitators.

In an effort to characterize the performance of self-inflating resuscitators, three examples of three models were subjected to laboratory testing: the Ohio Hope II resuscitator (Ohio Medical Products, Madison, WI), the PMR-2 resuscitator (Puritan Medical Products, Lenexa, KS), and the Laerdal resuscitator (AS Laerdal, Stavanger, Norway). The devices were connected to a test lung and compressed at frequencies of from 10 to 60 and at greater than 60 breaths per minute at 5, 10, and 15 L/min of flow. These devices were used with and without a reservoir and were compressed at less than and more than the pop-off valve pressures. The results revealed that all devices equipped with reservoirs delivered a significantly higher oxygen concentration than those without (P less than .001), and that activation of the pop-off valve significantly reduced Fio2 under all conditions (P less than .005). The pop-off valves for each device were activated throughout a wide range of pressures, the Laerdal 41 to 72 cm H2O, PMR-2 51 to 97 cm H2O, and the Ohio Hope II 38 to 106 cm H2O, well in excess of the manufacturer's specifications. Only the Laerdal with reservoir was able to deliver an Fio2 of greater than 0.9 when compressed at more than the pop-off valve pressure at rates of up to 30 breaths per minute using flows of 10 L/min, and it was the only device to produce Fio2 values of greater than 0.9 at all rates to 60 breaths per minute when compressed at less than the pop-off valve pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

The role of axillary dissection in mammographically detected carcinoma.

BACKGROUND: Axillary dissection remains a standard component of the treatment of invasive carcinoma of the breast. The presence of metastases to the regional lymph nodes guides adjuvant therapy and aids in determining prognosis. Mammography results in the discovery of small and often node-negative carcinomas of the breast. STUDY DESIGN: This 15-year, retrospective analysis investigated whether certain patients with small tumors could be spared the morbidity of axillary dissection. RESULTS: Medical records showed that from January 1980 to May 1995, 4,543 needle localization biopsies were done at York Hospital because of abnormalities detected on mammograms. Of these, 703 (15.5 percent) proved to be carcinoma. Of the carcinomas, 68 percent were infiltrating ductal carcinoma, 26 percent were ductal carcinoma in situ, and 5.4 percent were infiltrating lobular carcinoma. Axillary dissection was done on 588 patients, and 88.1 percent of the patients had no metastases to axillary lymph nodes. No axillary metastases were present in 109 patients with ductal carcinoma in situ who underwent axillary lymph node dissection or in 21 patients with microscopic invasive tumors. Only two of 54 patients with a T1a tumor (tumor [T], < or = 0.5 cm) had positive axillary nodes. Only one of 29 patients with a well-differentiated T1b tumor (T, > 0.5 to < or = 1 cm) had metastatic axillary nodes. In the presence of negative axillary lymph nodes, 19.2 percent of patients with a T1a tumor, 33.7 percent of patients with a T1b tumor, 60 percent of patients with a T1c tumor (T, > 1 to < or = 2 cm), and 78.9 percent of patients with a T2 tumor (T, > 2 cm) were given adjuvant chemotherapy or hormonal therapy. CONCLUSIONS: Patients with ductal carcinoma in situ and microscopic invasive tumors do not require node dissections. Possibly patients with T1a tumors and patients with well-differentiated, estrogen-receptor positive, progesterone-receptor positive, T1b tumors can also be spared axillary node dissection. By following this approach on occasion, patients with positive nodes might not undergo axillary lymph node dissection, but they may still be offered adjuvant therapy.

Outcome of shunted posthemorrhagic hydrocephalus in premature infants.

Patient histories of 29 infants were reviewed whose birth weights were less than 2,000 gm and who had received ventricular shunts in the neonatal period for posthemorrhagic hydrocephalus. This procedure was performed at a time when routine screening of low birth weight infants for intracranial hemorrhage was not undertaken and serial lumbar puncture usually was not employed. The overall outcome was poor, with 62% of shunted infants either dying or surviving with moderate or severe handicap. Neurodevelopmental outcome was associated with the interval between the diagnosis of hydrocephalus and shunting; an adverse outcome was associated with an increased interval. Current practices for treating posthemorrhagic hydrocephalus are discussed.

Bathing premature infants: physiological and behavioral consequences.

BACKGROUND: Routine procedures are a large component of the caretaking day for preterm infants. Such procedures can have profound adverse effects on an infant's condition, to the point of disrupting normal growth and development. Despite this evidence, routine procedures are perpetuated in the neonatal ICU. OBJECTIVE: To determine the physiological and behavioral effects of a supposedly beneficial procedure, a sponge bath, on premature infants. METHODS: The study sample consisted of 14 preterm neonates with no neurological abnormalities at two tertiary neonatal ICUs. The ages of the subjects were 28.1 to 31.8 weeks postconception and 4 to 25 days after birth. The study was a prospective, quasi-experimental, repeated-measures design in which each infant acted as his or her own control. Oxygen delivery, heart rate, oxygen saturation, and behavioral responses were continuously recorded by computer or real-time videotape. Physiological and behavioral parameters were compared across three phases: 10 minutes before a bath (baseline), during a standardized bath, and 10 minutes after the bath. RESULTS: Physiological and behavioral disruptions occurred throughout the bath phase and in many cases beyond that phase. These disruptions included significant increases in heart rate, cardiac oxygen demand, and frequency of behavioral motoric cues. Significant decreases in oxygen saturation also accompanied the bath. Nine infants required increased concentrations of ambient oxygen. A significant association was found between physiological components and the frequency and timing of behavioral motoric cues. CONCLUSIONS: The results provide further evidence that routine care is not innocuous to neonates. Routine sponge bathing is not recommended for care of ill premature infants.

Association between autonomic and motoric systems in the preterm infant.

In the clinical setting, fetal and infant movement is used as an indicator of central nervous system and neurobehavioral developmental status. Current models of neurobehavioral development include the synactive theory of neonatal behavioral organization, which defines and describes the interaction between five subsystems. Results of testing synchronous interaction between two of those systems--the autonomic and motoric subsystems in preterm infants--are reported here.

Neonatal stress reactivity and cortisol.

Existing data point to the fact that adrenocortical responses are, at least in part, valid representatives of the stress response in term and some preterm infants. At the same time, however, there is conflict regarding the use of cortisol levels as a diagnostic tool in the neonatal intensive care unit. The article reviews the concept of neonatal intensive care unit stress and neonatal stress response development and provides a comprehensive literature review of cortisol production in term and preterm neonates. A neonatal stress response model is presented along with implications for caregiving.

Infant handling in the NICU: does developmental care make a difference? An evaluative review of the literature.

Infant handling and disruptions in the neonatal intensive care unit are environmental stressors over which nurses have the most control. Two of the major goals of developmental care are individualizing care by decreasing infant disruptions and handling by caregivers, and modulating or attenuating infant responses to the care they receive. However, it has yet to be established to what extent these goals have been achieved. This article will provide a comparative review of selected literature to ascertain what effect, if any, the introduction of developmental care has had on infant handling or disruption in the neonatal intensive care unit.

Induction of the human protein P56 by interferon, double-stranded RNA, or virus infection.

P56 is the most abundant protein induced by interferon (IFN) treatment of human cells. To facilitate studies on its induction pattern and cellular functions, we expressed recombinant P56 as a hexahistidine-tagged protein in Escherichia coli and purified it to apparent homogeneity using affinity chromatography. A polyclonal antibody raised against this recombinant protein was used to show that P56 is primarily a cytoplasmic protein. Cellular expression of P56 by transfection did not inhibit the replication of vesicular stomatitis virus and encephalomyocarditis virus. P56 synthesis was rapidly induced by IFN-beta, and the protein had a half-life of 6 h. IFN-gamma or poly(A)(+) could not induce the protein, but poly(I)-poly(C) or an 85-bp synthetic double-stranded RNA efficiently induced it. Similarly, infection of GRE cells, which are devoid of type I IFN genes, by vesicular stomatitis virus, encephalomyocarditis virus, or Sendai virus caused P56 induction. Surprisingly, Sendai virus could also induce P56 in the mutant cell line P2.1, which cannot respond to either IFN-alpha/beta or double-stranded RNA. Induction of P56 in the P2.1 cells and the parental U4C cells by virus infection was preceded by activation of IRF-3 as judged by its translocation to the nucleus from the cytoplasm.

Nasal intermittent positive-pressure ventilation offers no advantages over nasal continuous positive airway pressure in apnea of prematurity.

A prospective, randomized, cross-over trial was performed to compare the efficacy of nasal intermittent positive-pressure ventilation with nasal continuous positive airway pressure in infants of less than 32 weeks of gestation. Continuous positive airway pressure was delivered at end-expiratory pressures of 4 cm H2O, while peak pressures of 20 cm H2O and end-expiratory pressures of 4 cm H2O were used during nasal intermittent positive-pressure ventilation at ventilatory rates of 20 breaths per minute. The frequency and extent of apnea and bradycardia during a 6-hour period in a patient receiving nasal continuous positive airway pressure were compared with a similar crossover period of nasal intermittent positive-pressure ventilation. Although the infants had slightly less frequent episodes of apnea per hour (0.6 +/- 0.7 vs 0.5 +/- 0.7) and bradycardia per hour (1.2 +/- 1.3 vs 0.9 +/- 1.0) during nasal intermittent positive-pressure ventilation, these differences were not significant. There were no significant differences in the severity of these events as assessed by the duration and fall in transcutaneous oxygen pressure during apnea and heart rate during bradycardia. There were no significant changes in blood gases throughout the study. Nasal intermittent positive-pressure ventilation appears to have no advantages over nasal continuous positive airway pressure in preventing apnea and does not alter gas exchange in infants of less than 32 weeks of gestation.

Potential effects of age-specific reference ranges for serum prostate-specific antigen.

Age-specific reference ranges for serum prostate-specific antigen (PSA) may improve this test for detecting prostate cancer. We have analyzed PSA levels from 10,024 men to determine the potential effects of these reference ranges. PSA levels (ng/ml) were grouped by patient age for comparison between standard (all ages: PSA < or = 4.0) and age-specific (< or = 49 years: PSA < or = 2.5; 50-59 years: PSA < or = 3.5; 60-69 years: PSA < or = 4.5; > or = 70 years: PSA < or = 6.5) reference ranges. Serum PSA correlated significantly with age (r = 0.33; p < 0.001). Fewer men > or = 60 years had elevated levels when age-specific reference ranges were applied (1,373 vs. 1,967; p < 0.001). Prostate biopsies and prebiopsy PSA levels from 865 men were reviewed. Sensitivities and specificities were calculated using both reference ranges. A significant increase in specificity with the age-specific reference ranges was seen for men > or = 70 years (58.6 vs. 34.2%; p < 0.001). There was, however, a concomitant decrease in sensitivity (77.6 vs. 91.7%; p < 0.001). We conclude serum PSA increases with age and we support the concept of age-specific reference ranges. However, the specificity of this test remains low, illustrating its limitations for prostate cancer detection.

Autophosphorylation of the Fes tyrosine kinase. Evidence for an intermolecular mechanism involving two kinase domain tyrosine residues.

The human c-fes proto-oncogene encodes a cytoplasmic tyrosine kinase (Fes) that is associated with multiple hematopoietic cytokine receptors. Fes tyrosine autophosphorylation sites may regulate kinase activity and recruit downstream signaling proteins with SH2 domains. To localize the Fes autophosphorylation sites, full-length Fes and deletion mutants lacking either the unique N-terminal or SH2 domain were autophosphorylated in vitro and analyzed by CNBr cleavage. Identical phosphopeptides of 10 and 4 kDa were produced with all three proteins, localizing the tyrosine autophosphorylation sites to the C-terminal kinase domain. Substitution of kinase domain tyrosine residues 713 or 811 with phenylalanine resulted in a loss of the 10- and 4-kDa phosphopeptides, respectively, identifying these tyrosines as in vitro autophosphorylation sites. CNBr cleavage analysis of Fes isolated from 32PO4-labeled 293T cells showed that Tyr-713 and Tyr-811 are also autophosphorylated in vivo. Mutagenesis of Tyr-713 reduced both autophosphorylation of Tyr-811 and transphosphorylation of Bcr, a recently identified Fes substrate, supporting a major regulatory role for Tyr-713. Wild-type Fes transphosphorylated a kinase-inactive Fes mutant on Tyr-713 and Tyr-811, suggesting that Fes autophosphorylation occurs via an intermolecular mechanism analogous to receptor tyrosine kinases.

An evaluation of theophylline for idiopathic apnea of infancy.

19 infants admitted with a diagnosis of infantile apnea who were found to have periodic breathing were given oral theophylline to determine its effect. They were studied at a mean age of 7.1 weeks (1-16.4 week). Each infant was studied during two naps, immediately before and 7 days following the institution of theophylline therapy, which averaged 2.8 h in duration during which electro-oculograms, end-tidal CO2, heart rate, impedance respirations, and transcutaneous pO2 (tcpO2) were continuously monitored. Theophylline therapy (mean dose 2.3 mg/kg q. 6 h) was associated with a significant reduction of apnea attack rates in both REM and non-REM sleep. Periodic breathing and the number of minutes per hour of sleep during which the TC pO2 was between 40-50 mm Hg in non-REM sleep also decreased. There was no significant reduction in the number of obstructive apneas, the number of bradycardias with apnea, nor the largest single fall in tcpO2. Theophylline can significantly reduce central apnea and periodicity in the age group studied, but the long-term effects of such therapy require further assessment.

Factors affecting outcome in hypoxic-ischemic encephalopathy in term infants.

Forty-nine term infants were prospectively shown to have hypoxic-ischemic encephalopathy (HIE). All infants survived the neonatal period, and all but two infants (seen at 12 months) were followed up to at least 27 months of age. Factors that significantly correlated with outcome included the Sarnat encephalopathy stage and the occurrence of intractable seizures not controlled by phenobarbital sodium alone. There was no association between the one- or five-minute Apgar score, the need for early ventilation, the EEG, the occurrence of seizures, and the subsequent outcome. There was no significant difference in outcome for those infants who received dexamethasone sodium phosphate (n = 29) v those who did not receive the drug (n = 20). A review of 97 term infants with HIE from a regional perinatal program during a one-year period (1979), including 35 of the 49 infants in the present study, did show a significant increase in morbidity and mortality for transported infants.