bluuebunny/crossref_metadata_2025 huggingface dataset:
Distribution of Nitrogen-13 from Labeled Nitrate (
13
NO
3
-
) in Humans and Rats
Authors: Witter James P. , Gatley S. John , Balish Edward
Published: October 2006

The body distribution of gavaged or intravenously administered nitrate labeled with nitrogen-13 was studied in humans and rats with the following results: (i) the labeled compound is not quickly absorbed from the stomach; (ii) the concentration of the label increases inside the lower intestinal tract (cecum and large intestine) when ingested or intravenously injected; and (iii) humans and rats have the capacity to store a portion of the label in their bodies. These observations indicate that depletion of body stores, the passage of nitrate down the gut, or the secretion of nitrate into the intestinal lumen may be a better explanation of the urinary, ileal, and fecal concentrations of nitrate and nitrite recently measured in humans than a bacterial nitrification reaction in the intestines, as suggested by Tannenbaum
et al.
Hyperthermia and Local Anesthetics: Potentiation of Survival of Tumor-Bearing Mice
Authors: Yatvin Milton B. , Clifton Kelly H. , Dennis Warren H.
Published: October 2006

Lidocaine infusion of a CA755 mammary adenocarcinoma growing in the hind leg of BDF1 mice results in a significant increase in the animals' survival when combined with heating for 1 hour in a 43.5°C water bath. This ability of local anesthetics to prolong survival following hyperthermia is consistent with the hypothesis that increases in membrane fluidity influence sensitivity to heat. In view of the extensive clinical experience with local anesthetics, the delay between clinical application and the observation that they potentiate the action of hyperthermia in animals may be reduced.
Delayed Neurotoxicity of Phenylphosphonothioate Esters
Authors: Abou-Donia Mohamed B.
Published: October 2006

Administration of a single oral dose of five phenylphosphonothioate esters produced delayed neurotoxicity in hens; their potency was, in descending order, cyanofenphos, EPN, desbromoleptophos, leptophos, and EPBP (Seven). Histological examination showed that in some hens there was marked axonal and myelin degeneration in the spinal cord and peripheral nerves. The results suggest that delayed neurotoxicity may be a general feature of phenylphosphonothioate insecticides.
Holographic Assessment of a Hypothesized Microwave Hearing Mechanism
Authors: Frey Allan H. , Coren Elaine
Published: October 2006

Exposure of the head to pulse-modulated microwaves induces the perception of a sound. It has been hypothesized that the electromagnetic energy is converted to acoustic energy in the skull and then conducted through the bone. Dynamic time-averaged interferometric holography showed that the predicted motion of head tissue did not occur. An alternative locus for this hearing effect is suggested.
Moment of Inertia: Psychophysical Study of an Overlooked Sensation
Authors: Kreifeldt John G. , Chuang Ming-Chuen
Published: October 2006

The distribution of mass in an object held in the hand, as described by its moment of inertia, is a fundamental and potent but largely unrecognized contributor to the object's "feel." A limited set of experiments has produced Weber fractions for human differential sensitivity to this property in the approximate range of 1/5 to 1/3, which is about ten times the Weber fraction reported for lifted weights.
Humans Deprived of Normal Binocular Vision Have Binocular Interactions Tuned to Size and Orientation
Authors: Levi Dennis M. , Harwerth Ronald S. , Smith Earl L.
Published: October 2006

A suprathreshold grating presented to one eye elevated the threshold for the discrimination of gratings similar in size and orientation presented to the fellow eye. The magnitude and stimulus specificity of these binocular interactions in human observers with normal binocular vision were similar to those in observers deprived of normal binocular visual experience; however, the latter showed a failure of binocular summation at threshold or subthreshold contrast levels. Whereas strabismus or amblyopia disrupted the normal excitatory interactions between the two eyes, cortical inhibitory binocular connections seem not to have been disrupted.
Elimination of Metabolic Cooperation in Chinese Hamster Cells by a Tumor Promoter
Authors: Yotti L. P. , Chang C. C. , Trosko J. E.
Published: October 2006

Wild-type Chinese hamster V79 cells (6-thioguanine-sensitive) reduce the recovery of 6-thioguanine-resistant cells when they are cultured together at high densities, through a form of intercellular communication (metabolic cooperation). Cooperation is inhibited by 12-
O
-tetradecanoyl phorbol-13-acetate, rescuing the 6-thioguanine-resistant cells. These results may be useful in the study of an aspect of the mechanism of tumor promotion and in assaying for promoters.
Myelination Inhibiting and Neuroelectric Blocking Factors in Experimental Allergic Encephalomyelitis
Authors: Seil Fredrick J. , Smith Marion E. , Leiman Arnold L. , Kelly James M.
Published: October 2006

Sensitization of Lewis rats with whole central nervous system tissue or with purified myelin induced both experimental allergic encephalomyelitis (EAE) and a serum factor which inhibited myelin formation in vitro. Sensitization with the encephalitogenic factor, myelin basic protein, induced EAE, but not the myelination inhibition factor. Sensitization with cerebroside induced neither EAE nor myelination inhibition factor. The serums from control animals without EAE as well as from animals sensitized with all of the above antigens blocked evoked electrical responses in vitro.
Inflammatory Effects of Endotoxin-Like Contaminants in Commonly Used Protein Preparations
Authors: Bito Laszlo Z.
Published: October 2006

Protein preparations from commercial suppliers are contaminated with bacterial endotoxins. The continued use of these preparations indicates that many researchers are unaware of this, and they may attribute all observed effects to the proteins themselves. Intravitreous injection of bovine serum albumin has an initial inflammatory effect on the rabbit eye which occurs before an immune reaction to the antigen itself can develop. This direct inflammatory effect can be fully accounted for by endotoxin-like contaminants which are present in protein preparations obtained from commercial suppliers. A pharmaceutical (U.S. Pharmacopeia) serum albumin preparation contains no detectable endotoxin, and has no initial inflammatory effect on the eye. Since endotoxins, even in minute amounts, have a variety of effects, the use of such contaminated protein preparations in biological research can lead to erroneous conclusions and should, therefore, be avoided.
African Trypanosomes: Cultivation of Animal-Infective
Trypanosoma brucei
in Vitro
Authors: Hirumi H. , Doyle J. J. , Hirumi K.
Published: October 2006

Trypanosoma brucei
grew in the presence of bovine fibroblast-like cells in Hepes-buffered RPMI 1640 medium with 20 percent fetal bovine serum for more than 220 days at 37°C. The organisms grown in this system were infective to mammalian hosts, retained the morphological and biochemical characteristics of long slender bloodstream forms, and displayed variant-antigen on their surfaces.
Cocaine: Plasma Concentrations After Intranasal Application in Man
Authors: Van Dyke C. , Barash P G. , Jatlow P. , Byck R.
Published: October 2006

Cocaine (1.5 milligrams per kilogram) was applied to the nasal mucosa of human subjects. The cocaine persisted in the plasma for 4 to 6 hours and reached peak concentrations of 120 to 474 nanograms per milliliter at 15 to 60 minutes. In that residual cocaine was detectable on the nasal mucosa for 3 hours, continuous absorption secondary to its vasoconstrictive action might explain its persistence in the plasma.
Fertilization-Induced Changes in Membrane Fluidity of Sea Urchin Eggs
Authors: Campisi Judith , Scandella Carl J.
Published: October 2006

By use of a spin label fatty acid, 5-doxylstearate, an increase in bulk membrane fluidity was observed after fertilization of two species of sea urchin eggs. Eggs partially activated by ammonia showed a similar effect. The data suggest that a structural change involving membrane lipids accompanies activation.
Cobra Venom Factor: Evidence for Its Being Altered Cobra C3 (the Third Component of Complement)
Authors: Alper C. A. , Balavitch D.
Published: October 2006

Evidence is presented that cobra venom factor, the anticomplementary protein in
Naja naja
venom, is modified cobra C3 (the third component of complement). Antiserum to the cobra venom factor cross reacts with human C3. A protein in cobra serum reacts strongly with antiserum to the venom factor and the former protein, like human C3, is converted by incubation of cobra serum with endotoxin, hydrazine, or simple storage at 37°C. Incubation of cobra venom factor with cobra serum destroys the C3 cleaving activity of the venom factor in human serum, whereas human C3b inactivator is ineffective. Thus, the cobra venom factor appears to be a form of C3 (perhaps C3b); its potent action in human serum probably derives from its lack of sensitivity to human C3b inactivator.
Child Spacing and Birth Order: Effect on Intellectual Ability in Two-Child Families
Authors: Belmont Lillian , Stein Zena , Zybert Patricia
Published: October 2006

The effect on intellectual ability of the spacing of the birth of siblings was studied in two series of young men from two-child families: (i) 535 pairs of brothers and (ii) 1511 unrelated firstborn and secondborn. Birth-order effect and level of ability were not influenced by length of interval between firstborn and secondborn.
β-Endorphin: Possible Involvement in the Antihypertensive Effect of Central α-Receptor Activation
Authors: Kunos George , Farsang Csaba , Ramirez-Gonzales Maria Dolores
Published: October 2006

Clonidine and L-α-methylnoradrenaline (but not D-α-methylnoradrenaline) increase the release of a substance with β-endorphin immunoreactivity from slices of brainstem of spontaneously hypertensive rats, but not that of normotensive rats. It was reported earlier that opiate antagonists inhibit the hypotensive action of clonidine and α-methyldopa in spontaneously hypertensive but not in normotensive rats and that β-endorphin has hypotensive effects of its own. Together, these findings indicate that release of β-endorphin by central α-receptor agonists may contribute to the antihypertensive action of these drugs.
Nonopiate Effects of Dynorphin and Des-Tyr-Dynorphin
Authors: Walker J. Michael , Moises Hylan C. , Coy David H. , Baldrighi Giulio , Akil Huda
Published: October 2006

Intracerebroventricular administration of dynorphin produced potent and long-lasting effects on motor function and the electroencephalogram in rats. In addition, local iontophoretic or pressure ejection of dynorphin consistently inhibited hippocampal unit activity. None of these effects were significantly affected by naloxone even at high doses. Moreover, a fragment of dynorphin that failed to displace any of a number of tritiated narcotics from rat brain homogenates produced similar effects on these physiological measures in vivo. On the basis of a variety of criteria for "opiate action," the results suggest that a second biologically active site within the dynorphin sequence is capable of quite potent but nonopiate effects.
Monoclonal Antibody to Thy-1 Enhances Regeneration of Processes by Rat Retinal Ganglion Cells In Culture
Authors: Leifer Dana , Lipton Stuart A. , Barnstable Colin J. , Masland Richard H.
Published: October 2006

Ganglion cells were dissociated from postnatal rat retinas, identified by specific fluorescent labels, and maintained in culture on a variety of substrates. Regeneration of processes by retinal ganglion cells was enhanced when the cells were plated on glass coated with a monoclonal antibody against the Thy-1 determinant. Plain glass and glass coated with polylysine, collagen, fibronectin, or other monoclonal antibodies supported the growth of neural processes, but were less effective than antibody to Thy-1.
Sodium Appetite in Sheep Induced by Cerebral Ventricular Infusion of Angiotensin: Comparison with Sodium Deficiency
Authors: Coghlan J. P. , Considine P. J. , Denton D. A. , Fei D. T. W. , Leksell L. G. , McKinley M. J. , Muller A. F. , Tarjan Eva , Weisinger R. S. , Bradshaw R. A.
Published: October 2006

Intraventricular administration of supraphysiological amounts of renin, nerve growth factor preparation, or angiotensin II greatly increased the consumption of water and hypertonic sodium bicarbonate solution by sheep. These effects were antagonized by intraventricular administration of drugs that prevent the formation of angiotensin II or block its receptors. The fact that these angiotensin-blocking drugs did not change the sodium intake of sodium-deficient sheep challenges the idea that central angiotensin action is involved in sodium appetite due to a deficiency.
Journey to the Center of the Cell: Role of the Receptosome
Authors: Pastan Ira H. , Willingham Mark C.
Published: October 2006

Fibroblasts contain a specific internalization pathway that carries hormones as well as some proteins and viruses from the cell surface to the cell interior. Initially, the ligands bind to mobile receptors that are randomly distributed on the cell surface. Next the ligand-receptor complexes are trapped and concentrated in specialized regions of the membrane termed bristle-coated pits. From the pit a smooth-walled vesicle containing the ligand forms and carries the ligand to the cell interior. Because of its role in receptor-mediated endocytosis, this vesicle has been termed a "receptosome."
Boradeption: A New Procedure for Transferring Water-Insoluble Agents Across Cell Membranes
Authors: Gallop Paul M. , Paz Mercedes A. , Henson Edward
Published: October 2006

A new process has been developed which is called "Boradeption" to signify boronic acid-dependent phase transfer of water-insoluble agents. Highly fluorescent boronic acid derivatives, FluoroBoras, are solubilized with a physiologically compatible carrier buffer containing a receptor group for boronate adduct formation. The system can be used to stain living cells. In another variation of the Boradeption concept, an insoluble reporter molecule containing a boronate receptor is solubilized with a carrier buffer containing a boronic acid functional group. The boronate-receptor complexes, which are in dynamic equilibrium, can be designed as vital stains and reagents for a variety of biological and medical applications.
Virus-Induced Corticosterone in Hypophysectomized Mice: A Possible Lymphoid Adrenal Axis
Authors: Smith Eric M. , Meyer Walter J. , Blalock J. Edwin
Published: October 2006

Infection of hypophysectomized mice with Newcastle disease virus caused a time-dependent increase in corticosterone and interferon production. Prior treatment with dexamethasone completely inhibited the virus-induced elevation in corticosterone concentration, but did not significantly alter the interferon response. Lymphocytes appear to be the most likely source of an adrenocorticotropin-like substance that is responsible for the increased corticosterone, since spleen cells from the virus-infected, but not from control or dexamethasone-treated, hypophysectomized mice showed positive immunofluorescence with antibody to adrenocorticotropin-(1-13 amide). Thus the adrenocorticotropin-like material and interferon appear to be coordinately induced and differentially controlled products of different genes. These findings strongly suggest the existence of a lymphoid-adrenal axis.
Drug-Induced Alterations of Cytokeratin Organization in Cultured Epithelial Cells
Authors: Knapp Loren W. , O'Guin W. Michael , Sawyer Roger H.
Published: October 2006

The distribution of keratin intermediate filaments, previously considered static in organization and imperturbable by conventional drugs used to alter the structure and organization of the cytoskeleton, can be altered significantly by treatment with colchicine and cytochalasin D. The loss of microfilaments and microtubules converts the keratin cytoskeleton from a branching, even distribution to a series of starlike structures whose filaments are maintained by multiple membrane attachment sites. These findings provide a means for manipulating cytokeratin organization to investigate the role of keratins in cytoskeletal structure and function.
Erythrocyte and Brain Forms of Spectrin in Cerebellum: Distinct Membrane-Cytoskeletal Domains in Neurons
Authors: Lazarides Elias , Nelson W. James
Published: October 2006

Chicken cerebellum expresses a polypeptide antigenically and biochemically related to the α subunit of spectrin, an erythrocyte membrane-cytoskeletal protein. Most of this polypeptide is associated with a brain specific spectrin subunit, γ-spectrin, and is localized in virtually all neuronal cell bodies and processes. Cerebellum also expresses polypeptides antigenically related to the β subunits of erythrocyte spectrin and these are also found in association with cerebellar α-spectrin but are confined to the plasmalemma of the neuronal cell bodies. This suggests that there is a mechanism for segregating different spectrin complexes into distinct membrane domains within a single cell.
Neurofilament Accumulation Induced in Synapses by Leupeptin
Authors: Roots Betty I.
Published: October 2006

The hypothesis that the usual absence of neurofilaments in synaptic terminals is due to their degradation by the calcium-activated protease present in axoplasm was tested by injecting leupeptin, which inhibits the protease, into the optic tectum of goldfish kept at 15° and at 25°C. The resulting accumulation of neurofilaments in synaptic terminals provides in vivo evidence in support of the hypothesis. The significance of these results and the potential uses of this pharmacological tool are discussed.
Glutamine-Selective Membrane Electrode That Uses Living Bacterial Cells
Authors: Rechnitz G. A. , Riechel T. L. , Kobos R. K. , Meyerhoff M. E.
Published: October 2006

A novel bioselective membrane electrode for L-glutamine has been constructed by coupling living bacteria of the strain
Sarcina flava
to a potentiometric ammonia gas sensor. Tests in aqueous standards and human serum show that the electrode combines excellent sensitivity and selectivity with rapid response and a useful lifetime of at least 2 weeks.
Potentiation of Bleomycin Lethality by Anticalmodulin Drugs: A Role for Calmodulin in DNA Repair
Authors: Chafouleas James G. , Bolton Wade E. , Means Anthony R.
Published: October 2006

Treatment of exponentially growing Chinese hamster ovary cells with bleomycin causes a dose-dependent decrease in cell survival due to DNA damage. This lethal effect can be potentiated by the addition of a nonlethal dose of the anticalmodulin drug
N
-(4-aminobutyl)-5-chloro-2-naphthalenesulfonamide (W13) but not its inactive analog
N
-(4-aminobutyl)-2-naphthalenesulfonamide (W12). By preventing the repair of damaged DNA, W13 also inhibits recovery from potentially lethal damage induced by bleomycin. These data suggest a role for calmodulin in the DNA repair pathway.
Caffeine and Related Methylxanthines: Possible Naturally Occurring Pesticides
Authors: Nathanson James A.
Published: October 2006

Natural and synthetic methylxanthines inhibit insect feeding and are pesticidal at concentrations known to occur in plants. These effects are due primarily to inhibition of phosphodiesterase activity and to an increase in intracellular cyclic adenosine monophosphate. At lower concentrations, methylxanthines are potent synergists of other pesticides known to activate adenylate cyclase in insects. These data suggest that methylxanthines may function as natural insecticides and that phosphodiesterase inhibitors, alone or in combination with other compounds, may be useful in insect control.
Induction of Pituitary Lactotrope Differentiation by Luteinizing Hormone α Subunit
Authors: Bégeot Martine , Hemming Fiona J. , Dubois Paul M. , Combarnous Yves , Dubois Maurice P. , Aubert Michel L.
Published: October 2006

Addition of gonadotropin releasing hormone to cultures of fetal rat pituitary induced differentiation of lactotropes as revealed by immunocytochemistry. Antiserum to luteinizing hormone (LH) (recognizing native LH), but not antiserum to LH-β (recognizing both native LH and its β subunit), inhibited this induction. Further addition of highly purified LH-α subunit in culture medium also induced lactotrope differentiation. Thus, the α subunit may have a specific biological activity of its own with probable practical use in clinical investigations.
The Structure of Rat Preproatrial Natriuretic Factor as Defined by a Complementary DNA Clone
Authors: Seidman Christine E. , Duby Allan D. , Choi Edmund , Graham Robert M. , Haber Edgar , Homcy Charles , Smith John A. , Seidman J. G.
Published: October 2006

The structure of rat preproatrial natriuretic factor (preproANF) was determined by nucleotide sequence analysis of an ANF complementary DNA clone. PreproANF is composed of a hydrophobic leader segment (20 amino acids), a precursor containing one glycosylation site (106 amino acids), and ANF (24 amino acids). Atrial natriuretic factor is located at the carboxyl terminus of the precursor molecule. The human, mouse, and rat genomes each contain a single ANF gene which is highly conserved.
Endotoxin-Stimulated Opioid Peptide Secretion: Two Secretory Pools and Feedback Control in Vivo
Authors: Carr Daniel B. , Bergland Richard , Hamilton Allan , Blume Howard , Kasting Norman , Arnold Michael , Martin Joseph B. , Rosenblatt Michael
Published: October 2006

Small doses of endotoxin evoked a dramatic biphasic response of opioid peptide secretion into blood in sheep. The first phase began within minutes and coincided with a brief hypertensive response to endotoxin well before the appearance of fever or hypotension. The ratio of β-endorphin to β-lipotropin fell abruptly at the onset of the second phase of release, suggesting early depletion of a pool rich in β-endorphin and subsequent emergence of a pool rich in unprocessed precursor. The concentration of cerebrospinal fluid opioids increased tenfold during the second phase. Naloxone administration augmented endotoxin-induced opioid secretion in both early and late phases, suggesting a short-loop feedback regulation of stress-induced endorphin secretion.
A Cellular Mechanism of Classical Conditioning in
Aplysia
: Activity-Dependent Amplification of Presynaptic Facilitation
Authors: Hawkins R. D. , Abrams T. W. , Carew T. J. , Kandel E. R.
Published: October 2006

A training procedure analogous to differential classical conditioning produces differential facilitation of excitatory postsynaptic potentials (EPSP's) in the neuronal circuit for the siphon withdrawal reflex in
Aplysia
. Thus, tail shock (the unconditioned stimulus) produces greater facilitation of the monosynaptic EPSP from a siphon sensory neuron to a siphon motor neuron if the shock is preceded by spike activity in the sensory neuron than if the shock and spike activity occur in a specifically unpaired pattern or if the shock occurs alone. Further experiments indicate that this activity-dependent amplification of facilitation is presynaptic in origin and involves a differential increase in spike duration and thus in Ca
2+
influx in paired versus unpaired sensory neurons. The results of these cellular experiments are quantitatively similar to the results of behavioral experiments with the same protocol and parameters, suggesting that activity-dependent amplification of presynaptic facilitation may make a significant contribution to classical conditioning of the withdrawal reflex.
Monoclonal Antibody to Acetylcholine Receptor: Cell Line Established from Thymus of Patient with Myasthenia Gravis
Authors: Kamo Isao , Furukawa Shoei , Tada Aiko , Mano Yukio , Iwasaki Yuzo , Furuse Tsutomu , Ito Naoki , Hayashi Kyozo , Satoyoshi Eijiro
Published: October 2006

A human B cell line producing a monoclonal antibody to an antigenic determinant of acetylcholine receptors was established by cloning B cells that had been transformed in vitro by Epstein-Barr virus. The B cells were obtained from the thymus of a patient with myasthenia gravis. The antibody produced by the cell line precipitated acetylcholine receptors from denervated and innervated rat muscle and from human muscle, but did not show detectable response to the acetylcholine receptors from the electric organs of
Narke japonica
. The monoclonal antibody showed identical binding patterns in innervated and denervated rat muscles. Passive transfer of the monoclonal antibody into rats induced moderate muscle weakness and electromyographic changes characteristic of myasthenia gravis.
Mutation Affecting the 12th Amino Acid of the c-Ha-
ras
Oncogene Product Occurs Infrequently in Human Cancer
Authors: Feinberg Andrew P. , Vogelstein Bert , Droller Michael J. , Baylin Stephen B. , Nelkin Barry D.
Published: October 2006

A point mutation alters the 12th amino acid of the c-Ha-
ras
oncogene product p21 in a human bladder cancer cell line. This is, at present, the only mutation known to result in a human transforming gene. This mutation may therefore represent a possible target for mutagenesis leading to carcinogenesis in humans. By means of restriction enzyme analysis, 29 human cancers, including 20 primary tumor tissues, derived from organs commonly exposed to environmental carcinogens, were tested for the presence of this mutation. None of ten primary bladder carcinomas exhibited the mutation; nor did nine colon carcinomas or ten carcinomas of the lung. Thus the point mutation affecting the 12th amino acid of the c-Ha-
ras
gene product, while a valuable model for carcinogenesis, does not appear to play a role in the development of most human epithelial cancers of the bladder, colon, or lung.
Is Cytosolic Ionized Calcium Regulating Neutrophil Activation?
Authors: Pozzan Tullio , Lew Daniel P. , Wollheim Claes B. , Tsien Roger Y.
Published: October 2006

The concentration of cytosolic ionized calcium, [Ca
2+
]
i
, was measured in intact neutrophils by use of a fluorescent indicator trapped in the cytoplasm. A given rise of [Ca
2+
]
i
elicited by the chemotactic peptide formylmethionylleucylphenylalanine (FMLP) was associated with a much greater degree of superoxide generation and myeloperoxidase secretion than was the same or larger [Ca
2+
]
i
produced by a specific calcium ionophore, ionomycin, which bypasses cell surface receptors. Thus, FMLP appears to generate some important excitatory signal in addition to a rise in [Ca
2+
]
i
, and exocytosis and superoxide generation in neutrophils may not be simply dependent on [Ca
2+
]
i
as is widely supposed.
Synthesis of Kappa Light Chains by Cell Lines Containing an 8;22 Chromosomal Translocation Derived from a Male Homosexual with Burkitt's Lymphoma
Authors: Magrath Ian , Erikson Jan , Whang-Peng Jacqueline , Sieverts Hauke , Armstrong Gary , Benjamin David , Triche Timothy , Alabaster Oliver , Croce Carlo M.
Published: October 2006

Three cell lines were derived from a homosexual patient with probable acquired immunodeficiency syndrome and Burkitt's lymphoma. The cell lines produce an unusual strain of Epstein-Barr virus which will both transform cord blood lymphocytes and induce early antigens in Raji cells. Translocations between chromosomes 8 and 22 have occurred in all three lines, but the cells synthesize immunoglobulin M with light chains of the κ type, in contrast to the usual concordance between a translocation involving chromosome 22 and λ chain synthesis. Both κ genes and one λ gene are rearranged. These findings indicate either that translocation may occur as a separate event from immunoglobulin gene rearrangement or that the proposed hierarchical sequence of immunoglobulin gene rearrangements is not always adhered to. The data also imply that in cells containing a translocation between the long arm of chromosome 8 and a chromosome bearing an immunoglobulin gene, alteration of cellular
myc
expression may occur regardless of the immunoglobulin gene that is expressed.
Susceptibility of Skeletal Muscle to Coxsackie A
2
Virus Infection: Effects of Botulinum Toxin and Denervation
Authors: Andrew Clifford G. , Drachman Daniel B. , Pestronk Alan , Narayan Opendra
Published: October 2006

Coxsackie A viruses can infect denervated but not innervated mature skeletal muscles. The role of synaptic transmission in preventing susceptibility to Coxsackievirus infection was studied by surgically denervating leg muscles of mice or injecting the muscles with botulinum toxin to block quantal release of acetylcholine. Control muscles were injected with heat-inactivated toxin. Subsequent injection of Coxsackie A
2
virus resulted in extensive virus replication and tissue destruction in the denervated and botulinum toxin-treated muscles, while the control muscles showed only minimal changes. This suggests that the susceptibility of skeletal muscle to Coxsackievirus infection is regulated by synaptic transmission.
Retinoblastoma: Clues to Human Oncogenesis
Authors: Murphree A. Linn , Benedict William F.
Published: October 2006

The retinoblastoma gene can be considered a model for a class of recessive human cancer genes that have a "suppressor" or "regulatory" function. The loss or inactivation of both alleles of this gene appears to be a primary mechanism in the development of retinoblastoma. Such a mechanism is in direct contrast to that of putative human oncogenes which are thought to induce tumorigenesis following activation or alteration. The high incidence of second primary tumors among patients who inherit one inactive retinoblastoma allele also suggests that this cancer gene plays a key role in the etiology of several other primary malignancies. Finally, the observation that extra nonrandom copies of specific chromosomal regions occur in some of these tumors provides circumstantial evidence that an "expressor" gene (possibly an oncogene) may be involved in retinoblastoma development.
Amphiphilic Secondary Structure: Design of Peptide Hormones
Authors: Kaiser E. T. , Kézdy F. J.
Published: October 2006

Peptide synthesis can be used for elucidating the roles of secondary structures in the specificity of hormones, antigens, and toxins. Intermediate sized peptides with these activities assume amphiphilic secondary structures in the presence of membranes. When models are designed to optimize the amphiphilicity of the secondary structure, stronger interactions can be observed with the synthetic peptides than with the naturally occurring analogs.
Inhibition of Platelet Aggregation by Monoclonal Antibody Reactive with β
2
-Microglobulin Chain of HLA Complex
Authors: Curry Russell A. , Messner Ronald P. , Johnson Gerhard J.
Published: October 2006

A mouse monoclonal antibody that reacts with β
2
-microglobulin, the light chain of class I major histocompatibility antigens, inhibited the second wave of human platelet aggregation induced by adenosine diphosphate and epinephrine and blocked aggregation and platelet protein phosphorylation induced by sodium arachidonate. Thrombin-induced platelet aggregation was inhibited at threshold concentrations but not at higher concentrations. The antibody also inhibited aggregation and secretion in response to thromboxane A
2
or the stable endoperoxide analog, U46619. These results suggest that β
2
-microglobulin in the histocompatibility complex is intimately associated with transmission of the endoperoxide-thromboxane signal at the platelet membrane.
Long-Term Potentiation of Hippocampal Synaptic Transmission Affects Rate of Behavioral Learning
Authors: Berger Theodore W.
Published: October 2006

Electrical stimulation techniques were used to produce a long-lasting potentiation of synaptic transmission in the hippocampus of naïve rabbits. Animals were then classically conditioned. Long-term potentiation of the hippocampus before training increased the rate at which animals subsequently learned the conditioning task. This result has significance for potential cellular mechanisms of associative learning.
Expression Cloning of Human EGF Receptor Complementary DNA: Gene Amplification and Three Related Messenger RNA Products in A431 Cells
Authors: Lin Chijen R. , Chen William S. , Kruiger Wiebe , Stolarsky Lana S. , Weber Wolfgang , Evans Ronald M. , Verma Inder M. , Gill Gordon N. , Rosenfeld Michael G.
Published: October 2006

In order to further define the mechanisms by which polypeptide growth factors regulate gene transcription and cellular growth, expression cloning techniques were used to select human epidermal growth factor (EGF) receptor complementary DNA clones. The EGF 3′ coding domain shows striking homology to the transforming gene product of avian erythroblastosis virus (v-
erbB
). Over-expression of EGF receptors in A431 cell lines correlates with increased EGF receptor mRNA levels and amplification (up to 110 times) of the apparently singular EGF receptor gene. There appear to be three cytoplasmic polyadenylated RNA products of EGF receptor gene expression in A431 cells, one of which contains only 5′ (EGF binding domain) sequences and is postulated to encode the secreted EGF receptor-related protein.
Trans
-Acting Transcriptional Activation of the Long Terminal Repeat of Human T Lymphotropic Viruses in Infected Cells
Authors: Sodroski Joseph G. , Rosen Craig A. , Haseltine William A.
Published: October 2006

The transcription initiation signals for retroviruses lie within the long terminal repeat (LTR) sequences that flank the integrated provirus. Two subtypes of human T lymphotropic virus (HTLV) are associated with different disease phenotypes. In this article it is shown that marked differences exist in the ability of LTR sequences of these subtypes to function as transcriptional elements in differentiated cell types. It is also shown that trans-acting regulatory factors present in HTLV-infected cells stimulate gene expression directed by these LTR sequences in a type-specific manner. These results have implications for understanding the diverse biological effects of HTLV infection.
Molecular and Cell Isoforms During Development
Authors: Caplan Arnold I. , Fiszman Marc Y. , Eppenberger Hans M.
Published: October 2006

Development proceeds by way of a discrete yet overlapping series of biosynthetic and restructuring events that result in the continued molding of tissues and organs into highly restricted and specialized states required for adult function. Individual molecules and cells are replaced by molecular and cellular variants, called isoforms; these arise and function during embryonic development or later life. Isoforms, whether molecular or cellular, have been identified by their structural differences, which allow separation and characterization of each variant. These isoforms play a central and controlling role in the continued and dynamic remodeling that takes place during development. Descriptions of the individual phases of the orderly replacement of one isoform for another provides an experimental context in which the process of development can be better understood.
Polyribosomes Associated with Forming Acrosome Membranes in Guinea Pig Spermatids
Authors: Mollenhauer Hilton H. , Morré D. James
Published: October 2006

Ribosomes, some of which are arranged in polyribosomal configurations, are attached to specialized regions of the acrosomal membrane in guinea pig spermatids. This finding indicates a new functional dimension for the acrosomal membrane, that of protein synthesis, and suggests that during acrosome formation, proteins of the acrosomal membrane or acrosomal contents need not be synthesized before or during passage through the Golgi apparatus.
Δ
9
-Tetrahydrocannabinol and 17β-Estradiol Bind to Different Macromolecules in Estrogen Target Tissues
Authors: Okey Allan B. , Bondy Gregory P.
Published: October 2006

Δ
9
-Tetrahydrocannabinol (Δ
9
-THC), added to the limit of its solubility, did not compete with tritiated 17β-estradiol for binding to estrogen receptor sites in mouse mammary or uterine cytosols. On sucrose density gradients of low-ionic strength, mammary cytosol labeled with [
3
H]estradiol exhibited a binding peak near the "8
S
" region typical of estrogen receptor whereas in cytosol labeled with Δ
9
-[
3
H]THC binding was limited to the nonspecific 4- to 5
S
region. Differences in sedimentation properties and reciprocal competition studies strongly refute previous claims that Δ
9
-THC binds to estrogen receptor and that by so doing it directly acts as an estrogen.
Myotonic Muscular Dystrophy: Altered Calcium Transport in Erythrocytes
Authors: Plishker Gordon A. , Gitelman Hillel J. , Appel Stanley H.
Published: October 2006

Erythrocytes from patients with myotonic muscular dystrophy accumulate calcium at a significantly higher rate than normal controls do. This increased rate of net accumulation appears related to an enhanced permeability of the membrane to calcium, rather than to an impairment in its active outward transport.
Sequential Interaction of Glia Maturation Factor with Insulin
Authors: Lim Ramon , Miller Joyce F.
Published: October 2006

Astroblasts in culture proliferated when exposed to glia maturation factor for at least 2 hours and then to insulin, but not when exposed in the reverse order. The sequential relation suggests that glia maturation factor is a competence factor.
Cyclic AMP Receptor Protein: Role in Transcription Activation
Authors: de Crombrugghe Benoit , Busby Stephen , Buc Henri
Published: October 2006

The structure of this pleiotropic activator of gene transcription in bacteria and its interaction sites at promoter DNA's as well as the role of this protein in the RNA polymerase-promoter interactions are reviewed.
Evolutionary Relatedness of
Plasmodium
Species as Determined by the Structure of DNA
Authors: McCutchan Thomas F. , Dame John B. , Miller Louis H. , Barnwell John
Published: October 2006

Malaria parasites can be grouped evolutionarily by analysis of DNA composition and genome arrangement. Those that vary widely with regard to host range, morphology, and biological characteristics fit into only a small number of distinctive groups. The DNA of the human parasite
Plasmodium falciparum
fits into a group that includes rodent and avian malarias and is unlike the DNA of other primate malaria parasites. The DNA of
Plasmodium vivax
, which is also a human parasite, fits into a distinctly different group that includes
Plasmodium cynomolgi
, a parasite of monkeys. The evolutionary lines suggested here appear to be consistent with similarities seen among malaria parasites with regard to gene sequence.
Antibodies to Human c-
myc
Oncogene Product: Evidence of an Evolutionarily Conserved Protein Induced During Cell Proliferation
Authors: Persson Håkan , Hennighausen Lothar , Taub Rebecca , DeGrado William , Leder Philip
Published: October 2006

Antisera to a synthetic c-myc peptide and to c-myc antigens synthesized from various portions of the human gene expressed in
Escherichia coli
were used in order to characterize the protein product of the human c-
myc
oncogene. Although the deduced molecular weight of the human c-myc protein is 49,000, these antisera precipitate a protein from human cells that migrates in sodium dodecyl sulfate-polyacrylamide gel as if its molecular weight were 65,000. In addition, the mouse c-myc protein, whether synthesized in cells or in a cell-free system directed by pure, synthetic messenger RNA, has analogous properties and is immunoprecipitated by the antiserum to the human c-myc protein. Similar proteins are immunoprecipitated from monkey, rat, hamster, and frog cells, suggesting evolutionary conservation of antigenic structure of the c-myc protein among vertebrates. In addition, and in a manner consistent with the behavior of its messenger RNA, the immunoprecipitable c-myc protein is sharply induced by the action of mitogens on resting human T cells.
Intracellular Calcium: Its Movement During Pentylenetetrazole-Induced Bursting Activity
Authors: Sugaya Eiichi , Onozuka Minoru
Published: October 2006

The intracellular calcium concentration in the cytoplasm decreased and the calcium concentration near the cell membrane increased during bursting activity induced by pentylenetetrazole in snail neuron. Incubation in medium containing cobalt chloride or lanthanum chloride did not change this tendency, which suggests that this calcium distribution change is due to the stored calcium in the subcellular structure moving toward the cell membrane.
Expression of Cellular Oncogenes in Human Malignancies
Authors: Slamon Dennis J. , deKernion Jean B. , Verma Inder M. , Cline Martin J.
Published: October 2006

Cellular oncogenes have been implicated in the induction of malignant transformation in some model systems in vitro and may be related to malignancies in vivo in some vertebrate species. This article describes a study of the expression of 15 cellular oncogenes in fresh human tumors from 54 patients, representing 20 different tumor types. More than one cellular oncogene was transcriptionally active in all of the tumors examined. In 14 patients it was possible to study normal and malignant tissue from the same organ. In many of these patients, the transcriptional activity of certain oncogenes was greater in the malignant than the normal tissue. The cellular
fes
(feline sarcoma) oncogene, not previously known to be transcribed in mammalian tissue, was found to be active in lung and hematopoietic malignancies.
Separation of Morphine Analgesia from Physical Dependence
Authors: Ling Geoffrey S. F. , MacLeod Janet M. , Lee Shay , Lockhart Stephen H. , Pasternak Gavril W.
Published: October 2006

Intravenous infusion of morphine sulfate in rats for 24 hours produced marked opioid dependence, manifested by a series of well-documented signs appearing after injection of the opiate antagonist naloxone. Treatment of rats with naloxonazine significantly reduced the analgesia associated with the morphine infusions for more than 24 hours. Furthermore, 14 of 16 withdrawal signs observed in naloxonazine-treated rats were virtually identical to those in rats that received morphine alone. These results raise the possibility that different receptor mechanisms mediate morphine analgesia and many of the withdrawal signs associated with morphine dependence.
Human Chorionic Gonadotropin Secreted by Preimplantation Embryos Cultured in Vitro
Authors: Fishel S. B. , Edwards R. G. , Evans C. J.
Published: October 2006

Human oocytes were collected by laparoscopy and fertilized and cultured in vitro. Human chorionic gonadotropin was detected in the medium surrounding two embryos cultured for more than 7 days after fertilization.
Prostaglandin E
2
: a Neuromodulator in the Central Control of Gastrointestinal Motility and Feeding Behavior by Calcitonin
Authors: Fargeas M. J. , Fioramonti J, , Buéno L.
Published: October 2006

Two micrograms of prostaglandin E
2
injected into the lateral ventricle of the brain in rats had the same anorectic and gastrointestinal motor effect as central administration of 0.02 unit of calcitonin. The effects of calcitonin were blocked by a previous intracerebroventricular administration of 0.25 milligram of indomethacin. These results suggest that both anorectic and gastrointestinal motor effects of calcitonin are centrally mediated by the release of prostaglandins.
Immune Response to Hepatitis B Surface Antigen: Enhancement by Prior Injection of Antibodies to the Idiotype
Authors: Kennedy R. C. , Adler-Storthz K. , Henkel R. D. , Sanchez Y. , Melnick J. L. , Dreesman G. R.
Published: October 2006

Anti-idiotype reagents that recognize a common idiotype associated with the combining site of antibodies to hepatitis B surface antigen (anti-HBs) were used to manipulate the immune response to hepatitis B surface antigen in BALB/c mice. The injection of antibodies to the idiotype before antigenic stimulation resulted in an increase in the number of cells secreting immunoglobulin M antibodies to hepatitis B surface antigen. Anti-HBs-secreting cells were also induced by administration of antibodies to the idiotype without subsequent antigen exposure. These findings indicate that the immune response to hepatitis B surface antigen in mice is regulated through an idiotype-anti-idiotype network.
Functional α
1
-Protease Inhibitor in the Lower Respiratory Tract of Cigarette Smokers Is Not Decreased
Authors: Stone Phillip J. , Calore James D. , McGowan Stephen E. , Bernardo John , Snider Gordon L. , Franzblau Carl
Published: October 2006

Cigarette smoking is the major risk factor for the development of pulmonary emphysema, a disorder that may result from an imbalance between the elastase and antielastase levels in the lungs. Decreased functional α
1
-protease inhibitor, an inhibitor of neutrophil elastase, might render smokers susceptible to elastase-catalyzed destruction of pulmonary elastic fibers and the development of emphysema. Binding and inactivation of isotopically labeled porcine pancreatic elastase and human neutrophil elastase by α
1
-protease inhibitor were measured in fluid obtained by bronchoalveolar lavage of volunteers. The inhibition of elastase-catalyzed solubilization of elastin and a tripeptide substrate were also determined. The mean level of functional α
1
-protease inhibitor in the bronchoalveolar lavage fluid of smokers was found to be equal to or greater than that of nonsmokers, contradicting reports by other investigators. Increased elastase derived from pulmonary neutrophils, rather than decreased functional α
1
-protease inhibitor, appears to be the main factor in the genesis of emphysema in smokers.
Cognitive Development and Social Policy
Authors: Firkowska Anna , Ostrowska Antonina , Sokolowska Magdalena , Stein Zena , Susser Mervyn , Wald Ignacy
Published: October 2006

The city of Warsaw was razed at the end of World War II and rebuilt under a socialist government whose policy was to allocate dwellings, schools, and health facilities without regard to social class. Of the 14,238 children born in 1963 and living in Warsaw, 96 percent were given the Raven's Progressive Matrices Test and an arithmetic and a vocabulary test in March to June of 1974. Information was collected on the families of the children, and on characteristics of schools and city districts. Parental occupation and education were used to form a family factor, and the district data were collapsed into two factors, one relating to social marginality, and the other to distance from city center. Analysis showed that the initial assumption of even distribution of family, school, and district attributes was reasonable. Mental performance was unrelated either to school or district factors; it was related to parental occupation and education in a strong and regular gradient. It is concluded that an egalitarian social policy executed over a generation failed to override the association of social and family factors with cognitive development that is characteristic of more traditional industrial societies.
Sympathetic Nervous Control of Cerebrospinal Fluid Production from the Choroid Plexus
Authors: Lindvall Maria , Edvinsson Lars , Owman Christer
Published: October 2006

The rabbit choroid plexus, responsible for the bulk production of cerebrospinal fluid, is well supplied by sympathetic nerves emanating in the superior cervical ganglia. Electrical stimulation of these nerves markedly reduces production of cerebrospinal fluid, measured by [
14
C] inulin dilution during ventricular perfusion, whereas sympathetic denervation enhances the rate of formation.
Enkephalin-Like Material Elevated in Ventricular Cerebrospinal Fluid of Pain Patients After Analgetic Focal Stimulation
Authors: Akil Huda , Richardson D. E. , Hughes John , Barchas Jack D.
Published: October 2006

Enkephalin-like activity has been measured in the ventricular cerebrospinal fluid of patients with intractable pain. Electrical stimulation of periventricular brain sites resulted in significant decrease in persistent pain in these subjects. This analgesia, which was blocked by naloxone in 80 percent of the cases, was accompanied by a significant rise in ventricular enkephalin-like activity, as measured by two different methods. The results present evidence of in vivo release of enkephalin-like material in humans and suggest that stimulation analgesia may be partially due to this release.