Chemical Studies in Lake Metabolisum. V-VIII. VII. Use of Radio-active Carbon (CH) for Measuring Organic Productivity in Lakes.

The mitotic apparatus is a structure of obvious biological and medical interest, but it has proved to be a difficult cellular machine to understand. The chemical composition of the spindle is only slightly elucidated, largely because of the difficulties in preparing useful isolates of the structure. Chemical studies of the mitotic spindle have been reviewed elsewhere (Mcintosh, 1977), and will not be discussed further here. One would think that structural studies on the mitotic apparatus (MA) in situ would be straightforward, but even with this approach there is some disagreement in the results obtained with various methods and by different investigators. In this paper I will review briefly the approaches which have been used in structural studies of the MA, pointing out the strengths and problems of each approach. I will summarize the principal findings of the different methods, and identify what seem to be fruitful avenues for further work.

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Ultrastructural Localization of Acetylcholinesterase in the Arcuate Nucleus and Median Eminence of the Rat

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079644 ◽

1977 ◽

Vol 35 ◽

pp. 440-441

Author(s):

K.A. Carson ◽

C.B. Nemeroff ◽

M.S. Rone ◽

J.S. Kizer ◽

J.S. Hanker

Keyword(s):

Choline Acetyltransferase ◽

Median Eminence ◽

Arcuate Nucleus ◽

Cholinergic Neurons ◽

Ultrastructural Localization ◽

Male Rats ◽

Neonatal Rats ◽

Good Marker ◽

Chemical Studies ◽

High Doses

Biochemical, physiological, pharmacological, and more recently enzyme histo- chemical data have indicated that cholinergic circuits exist in the hypothalamus. Ultrastructural correlates of these pathways such as acetylcholinesterase (AchE) positive neurons in the arcuate nucleus (ARC) and stained terminals in the median eminence (ME) have yet to be described. Initial studies in our laboratories utilizing chemical lesioning and microdissection techniques coupled with microchemical and light microscopic enzyme histo- chemical studies suggested the existence of cholinergic neurons in the ARC which project to the ME (1). Furthermore, in adult male rats with Halasz deafferentations (hypothalamic islands composed primarily of the isolated ARC and the ME) choline acetyltransferase (ChAc) activity, a good marker for cholinergic neurons, was not significantly reduced in the ME and was only somewhat reduced in the ARC (2). Treatment of neonatal rats with high doses of monosodium 1-glutamate (MSG) results in a lesion largely restricted to the neurons of the ARC.

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Structural and Chemical Studies of Pathological Fibers in Human Neurofibrillary Degeneration

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010012031x ◽

1985 ◽

Vol 43 ◽

pp. 726-729

Author(s):

K.S. Kosik ◽

L.K. Duffy ◽

S. Bakalis ◽

C. Abraham ◽

D.J. Selkoe

Keyword(s):

Monoclonal Antibodies ◽

Alzheimer Disease ◽

Human Brain ◽

Neurofibrillary Tangles ◽

Morphological Analysis ◽

High Specificity ◽

Cytoskeletal Proteins ◽

Neuritic Plaque ◽

Protein Chemistry ◽

Chemical Studies

The major structural lesions of the human brain during aging and in Alzheimer disease (AD) are the neurofibrillary tangles (NFT) and the senile (neuritic) plaque. Although these fibrous alterations have been recognized by light microscopists for almost a century, detailed biochemical and morphological analysis of the lesions has been undertaken only recently. Because the intraneuronal deposits in the NFT and the plaque neurites and the extraneuronal amyloid cores of the plaques have a filamentous ultrastructure, the neuronal cytoskeleton has played a prominent role in most pathogenetic hypotheses.The approach of our laboratory toward elucidating the origin of plaques and tangles in AD has been two-fold: the use of analytical protein chemistry to purify and then characterize the pathological fibers comprising the tangles and plaques, and the use of certain monoclonal antibodies to neuronal cytoskeletal proteins that, despite high specificity, cross-react with NFT and thus implicate epitopes of these proteins as constituents of the tangles.

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PEMANFAATAN KARBON AKTIF UNTUK MENGURANGI CEMARAN FORMALIN PADA IKAN ASIN JAMBAL ROTI

JURNAL TEKNOLOGI DAN INDUSTRI PANGAN ◽

10.33061/jitipari.v5i1.3137 ◽

2020 ◽

Vol 5 (1) ◽

Author(s):

Erma Ayu Nurcahyani ◽

Merkuria Karyantina ◽

Nanik Suhartatik

Keyword(s):

Active Carbon ◽

Food Preservation ◽

Hazardous Substances ◽

Salted Fish ◽

Hazardous Chemical ◽

The People ◽

Randomized Design ◽

Completely Randomized Design ◽

Safe Food ◽

Chemical Material

Ikan asin adalah metode untuk pengawetan makanan menggunakan kombinasi penggaraman dan pengeringan matahari. Di kalangan masyarakat, pembuatan ikan asin banyak menggunakan bahan kimia berbahaya seperti formalin. Penambahan bahan berbahaya mempengaruhi kualitas terutama keamanan. Makanan yang aman didefinisikan sebagai makanan yang terbebas dari cemaran biologi, kimia, mikrobiologi, yang dapat mempengaruhi kesehatan. Karbon aktif diduga bersifat polar yang mampu mengadsorpsi formalin. Tujuan penelitian ini adalah untuk mengetahui pengaruh pemberian karbon aktif dalam mengurangi cemaran formalin pada “jambal roti”. Rancangan percobaan yang digunakan untuk percobaan yaitu Rancangan Acak Lengkap (RAL) 2 faktorial, dengan faktor pertama yaitu konsentrasi karbon aktif 0, 3, dan 6% serta perlakuan kedua yaitu lama perebusan selama 5, 10, dan 15 menit. Penelitian ini dimulai dari pembuatan “jambal roti” dengan penambahan formalin dan perebusan dengan karbon aktif kemudian dianalisis uji kadar formalin, NaCl, protein, dan air. Hasil penelitian menunjukkan bahwa konsentrasi karbon aktif dan lama perebusan memberikan pengaruh yang signifikan pada kualitas jambal roti. Semakin tinggi konsentrasi karbon aktif dan lama perebusan maka semakin berkurangnya kadar formalin pada jambal roti. Hasil terbaik penelitian ini adalah karbon aktif 6% dan lama perebusan 15 menit. Menghasilkan formalin 3.21 ppm, NaCl 9.40%, protein 42.00%, dan air 30.02%. Kata kunci: Karbon Aktif, Formalin, Jambal Roti, Lama Perebusan. ABSTRACT Salted fish was a method for food preservation using combination of salting and sun drying. Among the people, the manufacture of salted fish use hazardous chemical material such as formaldehyde. The addition of hazardous substances affects the quality especially the safety. Safe food define as food that free from biological, chemical, microbiological contaminants that can affect health. Active carbon suspected to be polar which able to adsorb formaldehyde. The purpose of this research was to determine the influence of active carbon in reducing formaldehyde in salted fish “jambal roti”. The research used completely randomized design (CRD) with 2 factors, the first factor was the concentration of active carbon 0, 3, and 6% and the second was the boiling time (for 5, 10, and 15 min). This research was started from making “jambal roti” with the addition of formaldehyde and boiling with active carbon then analyzed for formaldehyde content, NaCl, protein, and moisture. The result showed that the concentration of active carbon and boiling time had a significant effect in quality salted fish “jambal roti”. The higher the concentration of active carbon and boiling time the more formaldehyde in “jambal roti” were removed. The best results of the research was 6% active carbon and 15 min of boiling time. Resulting 3.21 ppm of formaldehyde, 9.40% of NaCl, 42.00% of protein, and 30.02% of moisture. Keywords: Active Carbon, Formaldehyde, Jambal Roti, Boiling Time

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