Infant skin maturation: Preliminary outcomes for color and biomechanical properties.

BACKGROUND: Newborn infant skin changes after birth but studies have focused on the epidermal barrier. Dermal properties are relevant for care, but literature on postnatal changes is sparse. We further characterized skin maturational changes in lightness, color and response to biomechanical stress. METHODS: Normal skin sites from subsets of participants in a trial on the progression and stage of infantile hemangiomas were retrospectively examined. Standardized photographs were analyzed as L*, a*, and b* images. Biomechanics were measured with the Cutometer® . RESULTS: Color changed significantly with increasing age. Skin was darker and redder at 2.0 vs. 5.4, 8.5 and 12.8 months. Yellow color increased, with higher values at 12.8 vs. 2.0, 3.5 and 5.4 months. Chest tissue was consistently more elastic than arm and face sites, with significantly higher elasticity for the youngest and oldest age groups. Biological elasticity, elastic recovery, and total recovery were significantly greater for the oldest subjects. Viscoelasticity and elastic deformation were lower at 5.5 vs. 8.8 and 17.6 months. Arm viscoelastic creep was highest at 2.8 months. CONCLUSION: Skin maturation continues into year two. Increasing elasticity and decreasing viscoelasticity may reflect increased collagen structure/function. The findings have implications for prevention of skin injury associated with mechanical forces.

Biomechanical properties of infantile hemangiomas: clinical stage and effect of age.

BACKGROUND: Infantile hemangiomas (IHs) are benign vascular neoplasms with rapid capillary proliferation shortly after birth and slow involution with diminishing capillary proliferative activity, fibrosis, and fatty replacement over 7-10 years. METHODS: Hemangiomas and contralateral control sites in 88 subjects were measured using a suction device, 6-mm probe and 200 mbar negative pressure. Mechanical properties were assessed vs. controls and effects of body site, depth, clinical stage, histology diagnosis, and time. RESULTS: Biological elasticity, overall elasticity, net elasticity, total recovery, and elastic recovery were lower for IH vs. controls (P < 0.001). IH total deformation, elastic deformation, viscoelastic creep, and residual deformation were higher than controls (P < 0.001). Involuting IHs had lower viscoelasticity than proliferating and stable lesions (P < 0.001) and lower viscoelastic creep than stable IHs (P = 0.04). IH viscoelasticity was higher at 2.3 than 12.9, 23.7, and 61.0 months and at 4.9 and 8.1 than 61.0 months. IH elastic recovery varied by body site with larger differences vs. control for abdomen and leg. Elastic recovery differences from control were smaller at younger vs. older ages. CONCLUSIONS: Measurement of biomechanical properties may be useful to characterize IH progression and treatment response in clinical settings.

Universal DNA methylation age across mammalian tissues.

Aging, often considered a result of random cellular damage, can be accurately estimated using DNA methylation profiles, the foundation of pan-tissue epigenetic clocks. Here, we demonstrate the development of universal pan-mammalian clocks, using 11,754 methylation arrays from our Mammalian Methylation Consortium, which encompass 59 tissue types across 185 mammalian species. These predictive models estimate mammalian tissue age with high accuracy (r > 0.96). Age deviations correlate with human mortality risk, mouse somatotropic axis mutations and caloric restriction. We identified specific cytosines with methylation levels that change with age across numerous species. These sites, highly enriched in polycomb repressive complex 2-binding locations, are near genes implicated in mammalian development, cancer, obesity and longevity. Our findings offer new evidence suggesting that aging is evolutionarily conserved and intertwined with developmental processes across all mammals.

Intratumoral delivery of boronated epidermal growth factor for neutron capture therapy of brain tumors.

The gene for epidermal growth factor receptor (EGFR) is amplified or overexpressed in high-grade gliomas but is low or undetectable in normal brain. Recently, there has been increasing interest in using epidermal growth factor (EGF)-based bioconjugates as targeting agents for brain tumors. In the present study, we have investigated the potential use of boronated EGF as a delivery agent for boron neutron capture therapy, which is based on the capture reaction that occurs when 10B, a stable isotope, is irradiated with low-energy thermal neutrons. A fourth generation starburst dendrimer was boronated and linked to EGF using heterobifunctional reagents. Either wild-type or EGFR gene transduced C6 glioma cells (C6EGFR), which expressed 10(5)-10(6) receptor sites/cell, were stereotactically implanted into the right cerebral hemisphere of Fischer rats. Four weeks later, the rats received either i.v. or intratumoral (i.t.) injection of 131I-labeled boronated starburst dendrimer (BSD) or BSD-EGF. The biodistribution of 131I-BSD-EGF and 131I-BSD was studied by means of whole-body scintigraphy, autoradiography, and gamma scintillation counting. Following i.t. injection of 131I-BSD-EGF, 21.8% of the injected dose per gram tissue (% ID/g) was localized in C6EGFR tumors at 24 h and 16.3% at 48 h compared to 5 and 1.3% ID/g in C6 wild-type tumors, respectively, and 0.01 and 0.006% ID/g, respectively, for i.v. injected animals at the corresponding times. In contrast, following i.t. injection of BSD-EGF, only 0.01-0.1% ID/g was localized in the liver and spleen at 24 and 48 h compared to 5-12% ID/g following i.v. injection. Our data indicate that direct i.t. injection can selectively deliver BSD-EGF to EGFR-positive gliomas and suggest that intracerebral administration may be the most effective way for delivering EGF-based bioconjugates to EGFR-positive brain tumors.

Characterizing the Developmental Trajectory of Sirolimus Clearance in Neonates and Infants.

Sirolimus is increasingly being used in neonates and infants, but the mechanistic basis of age-dependent changes in sirolimus disposition has not been fully addressed yet. In order to characterize the age-dependent changes, serial sirolimus clearance (CL) estimates in individual young pediatric patients were collected and analyzed by population modeling analysis. In addition, sirolimus metabolite formation was also investigated to further substantiate the corresponding age-dependent change in CYP3A activity. The increasing pattern over time of allometrically size-normalized sirolimus CL estimates vs. age was well described by a sigmoidal Emax model. This age-dependent increase was also observed within each individual patient over a 4-year study period. CYP3A-dependent sirolimus metabolite formation changed in a similar fashion. This study clearly demonstrates the rapid increase of sirolimus CL over time in neonates and infants, indicating the developmental change. This developmental pattern can be explained by a parallel increase in CYP3A metabolic activity.

Thermostability at ultrahigh temperatures of thermolysin and a protease from a psychrotrophic Pseudomonas.

Thermal inactivation at 110-150 degrees C of thermolysin (EC 3.4.24.4), produced by the thermophile Bacillus thermoproteolyticus, and the extracellular protease of Pseudomonas sp. MC60 a psychotroph, were investigated at 130 degrees C, both enzymes had approximately the same deltaH (22 kcal/mol) and deltaS (-13.5 cal/mol per degree) values. Both enzymes contain zinc and calcium. The amino acid compositions of the enzymes were similar except that MC60 protease exhibited a more typical tyrosine content. Comparable heat resistance at extreme temperatures of enzyme produced by psychrotrophic and thermophilic organisms emphasizes the difference between molecular properties that resist denaturation at elevated temperatures and those that allow reversible denaturation.

Development of a Pediatric Physiologically Based Pharmacokinetic Model for Sirolimus: Applying Principles of Growth and Maturation in Neonates and Infants.

This study describes the maturation of sirolimus clearance in a cohort of very young pediatric patients with vascular anomalies. The relationship between allometrically scaled in vivo clearance and age was described by the Emax model in patients aged 1 month to 2 years. Consistent with the observed increase, in vitro intrinsic clearance of sirolimus using pediatric liver microsomes showed a similar age-dependent increase. In children older than 2 years, allometrically scaled sirolimus clearance did not show further maturation. Simulated clearance estimates with a sirolimus physiologically based pharmacokinetic model that included CYP3A4/5/7 and CYP2C8 maturation profiles were in close agreement with observed in vivo clearance values. In addition, physiologically based pharmacokinetic model-simulated sirolimus pharmacokinetic profiles predicted the actual observations well. These results demonstrate the utility of a physiologically based pharmacokinetic modeling approach for the prediction of the developmental trajectory of sirolimus metabolic activity and its effects on total body clearance in neonates and infants.

Serotonin-dopamine interactions in the control of conditioned reinforcement and motor behavior.

These studies addressed the question of serotonin (5-HT)-dopamine (DA) interactions with regard to reward-related behavior and motor activity in rats. The first experiment evaluated the effect of chronic treatment with fluoxetine (7 mg/kg/day), a serotonin-selective reuptake inhibitor, and buproprion (15 mg/kg/day), a dopamine reuptake inhibitor, on responding for conditioned reinforcement (CR). Chronic fluoxetine, but not buproprion, enhanced CR responding, and also potentiated cocaine-induced increases in CR responding. In the second experiment, animals received intra-accumbens infusions of either 5-HT (0, 1, 5, and 10 microg) or DA (10, 20 microg) prior to the conditioned reinforcement test. Dopamine, but not 5-HT, selectively facilitated CR responding, although 5-HT non-specifically increased responding as well. In the third and fourth experiments, it was demonstrated that intra-accumbens 5-HT causes increased motor activity, which was partially blocked by DA antagonists. The results suggest that chronically increased levels of 5-HT may facilitate reward-related behavior, but most likely via indirect modulatory mechanisms affecting general arousal and motor tone.

Boron neutron capture therapy: linkage of a boronated macromolecule to monoclonal antibodies directed against tumor-associated antigens.

Two new protein-binding polyhedral boron derivatives, isocyanatoundecahydro-closo-dodecaborate(2-) (1) and isocyanato(trimethylamino)octahydro-closo-decaborate(1 -) (2), were synthesized. These anionic isocyanates have long hydrolysis half-lives at pH 7 and react readily with primary or secondary aliphatic amines resulting in spontaneous urea linkage. Utilizing 1, 1100 boron atoms (7.3% boron by weight) were incorporated per molecule of a polyclonal antibody directed against human thymocytes (anti-thymocyte globulin) without denaturation. However, immunoreactivity of the conjugates was lost. Reaction of 1 and 2 with polylysine yielded boronated macromolecules containing 21-28% boron by weight (up to 2000 boron atoms per molecule). Polylysine boronated with 2 was successfully linked to antibody molecules employing the heterobifunctional linking molecules N-succinimidyl 3-(2-pyridyldithio)propionate (SPDP) and m-maleimidobenzoyl sulfosuccinimide ester (sulfo-MBS). Separation of the conjugated antibody from the free boronated macromolecules and unconjugated antibody molecules has been achieved by gel filtration on a Sephacryl S-300 column. By linking boronated polylysine to antibodies, greater than 10(3) boron atoms were incorporated with the attachment of this species to one or more sites on the antibody molecule. The resulting immunoconjugates contained greater than 10(3) boron atoms per molecule, retained their immunoreactivity, and potentially might be useful for the selective delivery of large numbers of boron atoms to tumor cells.

Synthesis and in vitro evaluation of boronated uridine and glucose derivatives for boron neutron capture therapy.

The following boron-containing nucleoside and glucose derivatives have been synthesized as potential boron delivery agents for boron neutron capture therapy (BNCT): 2'-O-(o-carboran-1-ylmethyl)uridine (4a), 3'-O-(o-carboran-1-ylmethyl)uridine (4b), sodium 7-(uridin-2'-ylmethyl)dodecahydro-7,8-dicarba-++ +nido-undecaborate (5), 5'-O-(o-carboran-1-ylmethyl)uridine (9), and 3'-O-(o-carboran-1-ylmethyl)-D-glucose (13). In vitro cellular uptake studies were performed with F98 rat glioma cells. Following 16 h incubation, cellular boron concentrations were determined by direct current plasma atomic emission spectroscopy (DCP-AES). Boron concentrations ranged from 65 to 103 micrograms/g of cells for the neutral closo structures compared with 1.5 micrograms/g of cells for the charged nido species. Cellular uptake of sodium mercaptoundecahydro-closo-dodecaborate (BSH), the compound currently being used in Japan for the treatment of malignant brain tumors by BNCT, was 2 micrograms/g of cells.

Boron-containing polyamines as DNA targeting agents for neutron capture therapy of brain tumors: synthesis and biological evaluation.

Three series of new boron-containing spermidine/spermine (SPD/SPM) analogues have been synthesized: N1- and N5-(4-carboranylbutyl) SPD/SPM derivatives (SPD-1, SPD-5, SPM-1, SPM-5); N1,N10-diethyl-N5-(4-carboranylbutyl)spermidine (DESPD-5), N1,N14-diethyl-N5-(4-carboranylbutyl)spermine (DESPM-5); and N5,N10-bis(4-carboranylbutyl)spermine (SPM-5,10). In vitro studies using rat F98 glioma cells have shown that these polyamines retain the ability to displace ethidium bromide from calf thymus DNA and are rapidly taken up by F98 glioma cells. However, their cytotoxicities, especially those with terminal N-substituted (SPD-1, SPM-1) boron compounds, are greater than those of SPD/SPM. Nevertheless, the groundwork has been created for a new class of boron-containing compounds that maybe useful for boron neutron capture therapy of tumors.

Synthesis and biological evaluation of boron-containing polyamines as potential agents for neutron capture therapy of brain tumors.

New boron-containing spermidine/spermine (SPD/SPM) analogues have been synthesized: N5-[4-(2-aminoethyl-o-carboranyl)butyl] and N5-{4-[(2,3-dihydroxypropyl)-o-carboranyl]butyl} SPD/SPM derivatives (ASPD-5, ASPM-5, DHSPD-5, and DHSPM-5) as well as N5-{[4-(dihydroxyboryl)phenyl]methyl}spermidine (BBSPD-5). These boronated polyamines retain their ability to displace ethidium bromide from calf thymus DNA and are rapidly taken up in vitro by F98 rat glioma cells. The in vitro toxicities of ASPD-5, ASPM-5, DHSPD-5, and DHSPM-5 are lower than those previously reported for N5-[4-(o-carboranyl)butyl] SPD/SPM derivatives (SPD-5 and SPM-5) but similar to those of native SPD and SPM. Very low toxicity was also observed for BBSPD-5. In vivo studies of ASPD-5 and BBSPD-5 were performed in mice bearing intracerebral implants of the GL261 glioma and subcutaneous implants of the B16 melanoma. The biodistribution data found in both tumor models suggest that the polyamines synthesized to date do not appear to be suitable boron agents for BNCT.

Electron spectroscopic imaging for high-resolution immunocytochemistry: use of boronated protein A.

In the present study we adapted electron spectroscopic imaging (ESI) for high-resolution immunocytochemistry. To accomplish this, we applied boronated protein A (B-pA) for indirect detection of specific antigenic sites using pre-embedding and post-embedding protocols. Isolated acinar cells were exposed to wheat germ agglutinin (WGA) and anti-WGA, followed by B-pA, to reveal WGA binding sites at the level of the plasma membrane. The cells were then embedded in Epon and unstained ultra-thin sections were examined by electron microscopy using the ESI mode. For post-embedding, ultra-thin sections of glutaraldehyde-fixed, Lowicryl-embedded pancreatic tissue were exposed to specific antibodies (anti-insulin or anti-amylase), followed by B-pA. The unstained sections were examined using the ESI mode. In both cases, boron was detected with high resolution either at the level of the plasma membrane of acinar cells, demonstrating WGA binding sites, or over secretory granules in pancreatic insulin-secreting cells or acinar cells, demonstrating insulin and amylase, respectively. These findings were compared to those obtained with the protein A-gold technique, and have demonstrated the analogy of both types of labeling. In addition, several control experiments assessed this novel approach. They have demonstrated the specificity of labeling and the high reactivity of B-pA, as well as its antibody-binding properties. Finally, electron energy loss spectral analysis confirmed the presence of boron in the tissue sections at sites where immunolabeling was detected. These results demonstrate that ESI is an appropriate approach for cytochemistry. Since the technique is based on detection of elements, spatial resolution is considered to be in the magnitude of 0.5 nm, which represents a major improvement in resolution over actual electron microscopic cytochemical techniques.

HLA-B8, immunoglobulins, and antibody responses in alcohol-related liver disease.

Ninety-two British, caucasian, alcoholic patients with liver disese were grouped on the basis of hepatic histology into fatty change, hepatitis with or without cirrhosis, and cirrhosis alone. Men with alcoholic hepatitis with or without cirrhosis showed an increased incidence of the histocompatibility antigen HLA-B8 (P less than 0.02). Increased measles antibody titres were found in patients without cirrhosis with or without hepatitis and were associated with the B8 phenotype in both sexes. Rubella antibody titres and percentage DNA-binding were raised in patients with cirrhosis and showed no association with the B8 phenotype. Concentrations of IgM and IgA were were raised in patients with stetosis and with hepatitis, while in patients with cirrhosis IgG concentrations were also increased. Low titres of autoantibodies were found in all histological groups. It is possible that the development of hepatitis in response to alcohol abuse may be influenced, at least in men, by a gene linked to the B locus. Otherwise, immune processes associated with alcohol-related liver disease are probably secondary phenomena.

Intrapartum uterine rupture.

The association between diethylstilbestrol (DES) exposure in utero and uterine malformations resulting in poor reproductive performance is well established. A case is presented of uterine rupture in a patient exposed to DES in utero who had no known predisposing factors for uterine rupture.

Perceived family functioning and adolescent suicidal behavior.

OBJECTIVE: Family problems increase the risk of adolescent suicidal behavior, but the specific dimensions of family functioning related to adolescent suicidal ideation and suicide attempts have not been identified clearly. This study examined the relationship between family functioning and adolescent suicidal ideation and suicide attempts. Participating adolescents included psychiatric inpatients who had attempted suicide (n = 35), high school students reporting suicidal ideation (n = 33), nonsuicidal psychiatric inpatients (n = 29), and nonsuicidal high school students (n = 37). METHOD: The Family Assessment Measure was used to assess adolescents' perceptions of family functioning on two levels: (1) the family system and (2) parent-adolescent dyadic relationships. RESULTS: The suicidal psychiatric inpatients and the suicidal high school students did not differ in their perceptions of family functioning and mother-adolescent relationships. However, both suicide groups reported more distress and family dysfunction than did the nonsuicidal high school students. Perceived family functioning and mother-adolescent relationships were significantly correlated with levels of depression, hopelessness, and self-esteem. CONCLUSIONS: Family functioning is important to consider when assessing and treating adolescents for suicidal behavior.

Self-esteem deficits and suicidal tendencies among adolescents.

OBJECTIVE: Self-esteem can play an important role in suicidal tendencies among adolescents. The present study was designed to examine the relationship between self-esteem deficits and suicidal tendencies in 254 adolescent psychiatric inpatients and 288 high school students. METHOD: The direct relationship between self-esteem and suicidal tendencies was examined by assessing suicidal ideation and history of suicide attempts. An indirect relationship between self-esteem and suicidality was examined by assessing depression and hopelessness. RESULTS: Differences were found across gender and hospitalization status, with males reporting higher self-esteem than females and high school students scoring higher in self-esteem than psychiatric inpatients. However, correlations among variables remained similar across gender and hospitalization status. Thus, low self-esteem was related to higher levels of depression, hopelessness, suicidal ideation, and an increased likelihood of having previously attempted suicide. Furthermore, self-esteem added to the understanding of suicidal ideation beyond what could be explained by depression and hopelessness. CONCLUSIONS: Low self-esteem was closely related to feelings of depression, hopelessness, and suicidal tendencies. Assessment of adolescents should include an evaluation of self-esteem, and therapy should attempt to address any self-esteem deficits.

Intralesional interferon-alpha-2b for the treatment of Peyronie's disease.

Peyronie's disease can best be described as a localized connective tissue disorder that primarily affects the tunica albuginea of the penis. The disease may be attributed to repetitive vascular trauma that initiates an inflammatory process and ultimately leads to the formation of a fibrous penile plaque. The plaque consists mainly of collagen and can significantly alter penile anatomy and function. Patients with Peyronie's disease will most often present with penile curvature, pain on erection, a palpable nodule most commonly located on the dorsal shaft of the penis, and erectile dysfunction. There is no definitive treatment for Peyronie's disease and the treating physician has many options. They may wait for spontaneous resolution of the plaque, choose medical therapy (which includes both oral and intralesional regimens), or opt for surgical management. The main purpose of this article is to discuss the advances in medical therapy for Peyronie's disease, in particular intralesional injection of interferon-alpha-2b (IFN-alpha-2b). Several studies have concluded that IFN-alpha-2b can be an effective modality of treatment and that many patients placed on a regimen of IFN-alpha-2b experienced a significant reduction in penile curvature, diminished pain with erection, and decreased size of the plaque. Further clinical studies are currently being undertaken to determine the precise quantity and frequency of administration of IFN-alpha-2b that is most effective with the least amount of side effects.