Effects of 12-0-tetradecanoylphorbol-13-acetate (TPA) on rat pheochromocytoma (PC12) cells: Interactions with epidermal growth factor and nerve growth factor

The phorbol ester tumor promoter 12-0-tetradecanoylphorbol-13-acetate (TPA) specifically inhibited the binding of radioiodinated epidermal growth factor (¹²⁵I-EGF) to rat pheochromocytoma (PC12) cells in a noncompetitive fashion with an apparent K_i of 11–26 nM. Both TPA and EGF elicited similar biological responses in PC12 cells including enhanced incorporation of ³H-choline and ³²P-orthophosphate into macromolecules, induction of ornithine decarboxylase, and stimulation of the phosphorylation of a 30,000 MW nonhistone, chromosome-associated protein. These effects were also elicited by nerve growth factor (NGF) which, in contrast to the former agents, is a differentiating stimulus for the PC12 cells. The effects of TPA were additive or more than additive to the effects of NGF and EGF. When PC12 cells were induced to differentiate by treatment with NGF for 72 hours, the binding of ¹²⁵I-EGF and responses to EGF were reduced by approximately 70%. The response of PC12 cells to the tumor promoter TPA was unaffected by treatment with NGF. Thus, the qualitatively similar effects of TPA and EGF seemed to be mediated through separate receptor systems with only the EGF receptor system reduced by NGF treatment.     

Dielectric studies of the binding of water to lysozyme

Dielectric dispersion measurements as a function of hydration are reported for lysozyme powder. The dispersion that occurs in the frequency range 10 kHz to 10 GHz can be analysed in terms of bound water molecules that form single or multiple hydrogen bonds, and the numbers found in these two categories agree well with recent X-ray data for lysozyme crystals. The dielectric data also indicate that at 20% ($\text{w}\text{w}$) hydration the bound water acts as a plasticizer to increase the vibrational freedom of the protein structure, and that this may be of relevance to the fact that the onset of enzymatic activity occurs at this hydration level. Also, a sudden transition in the polarizability of the protein-water system is found to occur at 7% ($\text{w}\text{w}$) hydration.     

Vitamin D supplements in pregnant Asian women: effects on calcium status and fetal growth.

In a double-blind trial of vitamin D supplements in pregnant Asian women calciferol (ergocalciferol, 1000 IU/day) was administered to 59 women and placebo to 67 controls during the last trimester. The two groups had similar distributions of maternal age, height, parity, number of vegetarians, countries of origin, and sex and gestation of the infants. At entry to the trial maternal serum 25-hydroxy vitamin D (25-OHD) concentrations were low in both treatment and control groups and significantly lower in vegetarians than non-vegetarians. Mothers in the treatment group gained weight faster in the last trimester than those in the control group, and at term they and their infants all had adequate plasma 25-OHD concentrations, Mothers and infants in the control group, however, had low plasma concentrations of 25-OHD and calcium and raised plasma alkaline phosphatase (bone isoenzyme) activity. Five of these infants developed symptomatic hypocalcaemia. Almost twice as many infants in the control group were small for gestational age (29% v 15%), but there were no significant differences between the two groups of infants in antropometric measurements. Infants in the control group, however, had larger fontanelles, suggesting impaired ossification of the skull. Because of the benefits to mothers and infants in the treatment group and the absence of side effects, vitamin D supplements should be given to all pregnant Asian women in the United Kingdom.     

Salicylates and reversible hearing loss

Skin and soft tissue infections were studied in 21 seriously ill narcotic addicts who had been admitted to hospital. Subcutaneous abscesses were present in 14 patients; cellulitis was noted in 3, pyomyositis in 2 and necrotizing fasciitis in 2. In four patients there was septicemia. Infections in 14 patients (66.6 percent) were associated with anaerobic bacteria, which were the exclusive isolates in 6 patients. In seven patients (33.3 percent) isolates were exclusively aerobic bacteria and in eight both aerobes and anaerobes were present. The anaerobic isolates were clostridia (six), peptostreptococci (five), bacteroides (five), peptococci (three), and one of each of Veillonella, Propionibacterium, Eubacterium, Fusobacterium and Actinomyces. Staphylococcus aureus, generally thought to be the most common cause of subcutaneous infections in addicts, was found only in four (19 percent) patients. The other aerobic isolates were Klebsiella (five) and Enterobacter (four) species. When clinical features or the Gram stain of pus suggest that anaerobic bacteria may be present, antibiotic therapy should be directed against both aerobic and anaerobic bacteria until culture results are available.     

DNA-negative temperature-sensitive mutants of herpes simplex virus type 1: patterns of viral DNA synthesis after temperature shift-up.

Temperature-sensitive mutants of herpes simplex virus type 1 belonging to four DNA- complementation groups exhibited two distinct patterns of viral DNA synthesis after shift-up to the nonpermissive temperature. In cultures infected with mutants belonging to complementation groups A, C, and D, little or no viral DNA was synthesized after shift-up. In cultures infected with a mutant in complementation group B, nearly normal amounts of viral DNA were synthesized after shift-up.     

On the Presence of a Transverse System in Tunicate Muscle

Abstract Ultrastructural investigation of the caudal muscle cells in the tadpole larva of the ascidian Dendrodoa grossularia has shown that in this species, a transverse tubular system is present; diad and triad couplings are formed with the sarcoplasmic reticulum. Peripheral couplings of the sarcoplasmic reticulum are infrequent and have only been observed at the longitudinally apposed faces of the caudal muscle cells.     

Efficient Organic Solar Cell with 16.88% Efficiency Enabled by Refined Acceptor Crystallization and Morphology with Improved Charge Transfer and Transport Properties

Single‐layered organic solar cells (OSCs) using nonfullerene acceptors have reached 16% efficiency. Such a breakthrough has inspired new sparks for the development of the next generation of OSC materials. In addition to the optimization of electronic structure, it is important to investigate the essential solid‐state structure that guides the high efficiency of bulk heterojunction blends, which provides insight in understanding how to pair an efficient donor–acceptor mixture and refine film morphology. In this study, a thorough analysis is executed to reveal morphology details, and the results demonstrate that Y6 can form a unique 2D packing with a polymer‐like conjugated backbone oriented normal to the substrate, controlled by the processing solvent and thermal annealing conditions. Such morphology provides improved carrier transport and ultrafast hole and electron transfer, leading to improved device performance, and the best optimized device shows a power conversion efficiency of 16.88% (16.4% certified). This work reveals the importance of film morphology and the mechanism by which it affects device performance. A full set of analytical methods and processing conditions are executed to achieve high efficiency solar cells from materials design to device optimization, which will be useful in future OSC technology development.