Sexuality, color, and stigma among Northeast Brazilian women.

Despite its international image as a sexually free-spirited country, local attitudes toward morality of sexual behavior remain complex throughout Brazil, especially in rural areas and the conservative Northeast region. In addition, notwithstanding its official ideology of nonracism, African ancestry as judged through personal appearance (color) constitutes a significant social and economic disadvantage. Using Goffman's idea of "spoiled identity" as a starting point, I show how locals use sexual behavior as a multivocal symbol of moral status in women, and how spoiled sexual reputation interacts with other stigmatized statuses, especially color.

Women, alcohol and work: interactions of gender, ethnicity and occupational culture.

Patterns of alcohol use are affected by culture and history and interwined with the rhythms of work life. The 20th century economic shift toward industrial and service jobs coupled with the increasing presence of women in the workplace has revolutionized U.S.

Preferential dendritic localization of pericentriolar material in hippocampal pyramidal neurons in culture.

Centrosomes are unique cytoplasmic structures which serve as microtubule organizing centers (MTOC). In most animal cells centrosomes consist of one or more pair of centrioles surrounded by electron dense amorphous pericentriolar material (PCM) responsible for nucleation of microtubules. In the present study we analyzed the pattern of induction and localization of proteins of the PCM at different stages of neuronal development in cell cultures prepared from the embryonic hippocampus.

Characterization of posttranslational modifications in neuron-specific class III beta-tubulin by mass spectrometry.

Class III beta-tubulin, isolated from adult bovine brain, is resolved into at least seven charge variants on isoelectric focusing gels. To identify the posttranslational modifications responsible for this heterogeneity, a mixture of brain tubulins was treated with cyanogen bromide and the C-terminal fragments from the class III beta-tubulin isoforms were then isolated by binding them to the monoclonal antibody TuJ1. Combined use of tandem mass spectrometry and both subtractive and automated Edman degradation chemistry on the isolated peptides indicates that many of the isoforms differ by phosphorylation at Ser-444 plus attachment of one to six glutamic acid molecules to the side chain of the first glutamate residue, Glu-438, in the C-terminal sequence Tyr-Glu-Asp-Asp-Glu-Glu-Glu-Ser-glu-Ala-Gln-Gly-Pro-Lys.

Reactivation of isolated mitotic apparatus: metaphase versus anaphase spindles.

Mitotic spindles isolated from sea urchin eggs can be reactivated to undergo mitotic processes in vitro. Spindles incubated in reactivation media containing sea urchin tubulin and nucleotides undergo pole-pole elongation similar to that observed in living cells during anaphase-B. The in vitro behavior of spindles isolated during metaphase and anaphase are compared.

Posttranslational modification of class III beta-tubulin.

The charge heterogeneity of class III beta-tubulin (beta III) during neural development was analyzed by high-resolution isoelectric focusing/two-dimensional polyacrylamide gel electrophoresis in combination with site-specific proteolytic digestion and immunological detection. The number of beta III isoforms (charge variants) gradually increases from one in embryonic brain to seven in adult brain. All of the charge heterogeneity is due to posttranslationally modified sites located within the extreme C-terminal region of the beta III polypeptide.

Inhibition of mitosis in fertilized sea urchin eggs by inhibition of the cyclic AMP-dependent protein kinase.

Inhibition of cAMP-dependent protein kinase activity by microinjection of a specific physiologic protein inhibitor into sea urchin eggs inhibits the first cleavage after fertilization. Inhibition apparently occurs at some time prior to or during formation of the mitotic spindle. Measurement of the total protein kinase activity of sea urchin egg homogenates after fertilization showed that cAMP-dependent phosphorylation increases after fertilization and then declines prior to or at the time of the first cleavage.

Beta-tubulin epitope expression in normal and malignant epithelial cells.

The expression of a unique beta-tubulin isoform (class III) was monitored in squamous cell carcinoma (SCC) and normal epithelial cells using a monoclonal tubulin antibody called TuJ1. Whole tissue homogenates of SCC, normal tissue, SCC grown in nude mice, and SCC cultured cells were examined using sodium dodecyl sulfate polyacrylamide gel electrophoresis and Western blot. TuJ1 antibody localization was performed using peroxidase immunostaining on paraffin sections of SCC, normal tissue, nude mouse SCC, and immunofluorescent microscopy of SCC cultured cells.

The expression and posttranslational modification of a neuron-specific beta-tubulin isotype during chick embryogenesis.

Five beta-tubulin isotypes are expressed differentially during chicken brain development. One of these isotypes is encoded by the gene c beta 4 and has been assigned to an isotypic family designated as Class III (beta III). In the nervous system of higher vertebrates, beta III is synthesized exclusively by neurons.

Disassembly of the nuclear envelope of spisula oocytes in a cell-free system.

Nuclei isolated from oocytes of the surf clam Spisula solidissima are disassembled when exposed to extracts from maturing oocytes. In the course of this process the nuclear lamina undergoes a marked reduction in size and the nuclear membrane appears to be fragmented into vesicles. These events are accompanied by extensive phosphorylation of the oocyte 67-kDa lamin and its solubilization.

Angels with wet wings won't fly: maternal sentiment in Brazil and the image of neglect.

Current theories of fatalism and neglect and current descriptions of childhood illness in impoverished Northeastern Brazil are evaluated. Findings of an ongoing multidisciplinary project indicate that neglect and fatalism theories are incomplete as applied to the Brazilian Northeast. Intensive interviews and observations with bereaved mothers and traditional healers show that mothers' failure to obtain medical care for severely ill children is due more to real-life bureaucratic and geographic barriers to access than to fatalistic or neglectful attitudes on the part of the poor, that mothers' flat affect in response to infant deaths is due more to folk Catholic beliefs than to lack of emotional attachment to infants, that fatalistic statements are often post hoc and do not indicate fatalistic behavior, and that decisions about whether to treat severely ill infants are made by mothers and families in consultation with traditional healers in accord with a folk system of classification of high risk infants.

Mystification of a simple solution: oral rehydration therapy in northeast Brazil.

Problems in the control of access to and administration of oral rehydration therapy (ORT) in Northeast Brazil are described and discussed. Administration of ORT is controlled by the medical establishment, which is in general opposed to the use of home made and home administered ORT. Reasons for this resistance are discussed in terms of anthropological theories on ritual, mystification, and the social construction of reality; the medical establishment is described as using ORT as a symbol and guarantor of social status and power.

In vitro reactivation of anaphase B in isolated spindles of the sea urchin egg.

Spindles may be isolated from sea urchin eggs so that some mitotic processes can be reactivated in vitro. The isolation media allow spindles to remain stable for days. Transfer of the spindles to reactivation media results in loss of birefringence and breakdown of the matrix within which the microtubules function.

Purification and characterization of a sea urchin egg Ca2+-calmodulin-dependent kinase with myosin light chain phosphorylating activity.

The crude actomyosin precipitate from sea urchin (Arbacia punctulata) egg extracts contains Ca2+-sensitive myosin light chain kinase activity. Activity can be further increased by exogenous calmodulin (CaM). Egg myosin light chain kinase activity is purified from total egg extract by fractionating on three different chromatographic columns: DEAE ion exchange, gel filtration on Sephacryl-300, and Affi-Gel-CaM affinity.

The binding of MAP-2 and tau on brain microtubules in vitro: implications for microtubule structure.

We have presented data that indicate that MAP-2 associates with brain microtubules at nonrandomly distributed sites, whose distribution on the microtubule polymer can best be described by the 12-dimer MAP superlattice originally described by Amos; because of the additional spacings, however, between MAP-2 projections observed on MAP-2-saturated microtubules, we suggest that the 6-dimer MAP superlattice, or what we will call the double Amos superlattice, more completely specifies the total set of MAP-binding sites on cytoplasmic microtubules. Second, we have shown that brain microtubules reassembled in vitro contain a heterogeneous population of MAP-binding sites, which differ in their affinities for the two MAPs, MAP-2 and tau. Third, we have shown that microtubule populations that differ in their MAP content have subtle, but detectable differences in their tubulin isotype composition.

The distribution of tau in the mammalian central nervous system.

We have determined the biochemical and immunocytochemical localization of the heterogeneous microtubule-associated protein tau using a monoclonal antibody that binds to all of the tau polypeptides in both bovine and rat brain. Using immunoblot assays and competitive enzyme-linked immunosorbent assays, we have shown tau to be more abundant in bovine white matter extracts and microtubules than in extracts and microtubules from an enriched gray matter region of the brain. On a per mole basis, twice-cycled microtubules from white matter contained three times more tau than did twice-cycled microtubules from gray matter.

Analysis of sea urchin egg cortical transformation in the absence of cortical granule exocytosis.

A burst of endocytosis accompanying microvillar elongation follows cortical granule exocytosis in normal sea urchin development. By 5 min postfertilization the burst is over and a lower level of endocytosis ensues (constitutive phase). To determine whether microvillar elongation and initiation of endocytosis are necessary concommitants of cortical granule exocytosis we utilized Chase's (1967, Ph.

Heterogeneity of microtubule-associated protein 2 during rat brain development.

The electrophoretic pattern of the large microtubule-associated protein, MAP2, changes during rat brain development. Immunoblots of NaDodSO4 extracts obtained from the cerebral cortex, cerebellum, and thalamus at 10-15 days after birth reveal only a single electrophoretic species when probed with any of three MAP2 monoclonal antibodies. By contrast, adult MAP2 contains two immunoreactive species, MAP2a and MAP2b.

Differential subcellular localization of tubulin and the microtubule-associated protein MAP2 in brain tissue as revealed by immunocytochemistry with monoclonal hybridoma antibodies.

The distribution and subcellular localization of tubulin and MAP2 in brain tissue were analyzed by immunocytochemistry with monoclonal hybridoma antibodies prepared against Chinese hamster brain tubulin and MAP2. We examined three anti-tubulin hybridoma antibodies (Tu3B, Tu9B, Tu12) specific for beta-tubulin, and two anti-MAP2 hybridoma antibodies (AP9,AP13). The specificity of each of the monoclonal antibodies was characterized by staining nitrocellulose electrophoretic blots of SDS-polyacrylamide gels of whole brain or hippocampal extracts.

Purification and characterization of oocyte cytoplasmic tubulin and meiotic spindle tubulin of the surf clam Spisula solidissima.

Assembly-competent tubulin was purified from the cytoplasm of unfertilized and parthogenetically activated oocytes, and from isolated meiotic spindles of the surf clam, Spisula solidissima. At 22 degrees C or 37 degrees C, Spisula tubulin assembled into 48-51-nm macrotubules during the first cycle of polymerization and 25-nm microtubules during the third and subsequent cycles of assembly. Macrotubules were formed from sheets of 26-27 protofilaments helically arranged at a 36 degree angle relative to the long axis of the polymer and were composed of alpha and beta tubulins and several other proteins ranging in molecular weight from 30,000 to 270,000.

Cytoplasmic tubulin from the unfertilized sea urchin egg: II. Variation of the intrinsic calcium sensitivity of Strongylocentrotus purpuratus egg tubulin as a function of temperature and brain microtubule-associated proteins.

Cytoplasmic tubulin purified from unfertilized sea urchin eggs self-assembles in the absence of microtubule-associated proteins (MAPs) [Suprenant and Rebhun, 1983; Detrich and Wilson, 1983] with a critical concentration for polymerization of 0.8 mg/ml at 15-18 degrees C, a value well below the 3 mg/ml tubulin present in these eggs [Pfeffer et al, 1976]. Studies of the calcium sensitivity of unfertilized S.