Yovita Harmiatun
Bagian Biologi, Fakultas Kedokteran Universitas Kristen Indonesia

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Etiologi dan Patogenesis Limfangioleiomiomatosis Yovita Harmiatun
Majalah Kedokteran UKI Vol. 25 No. 2 (2007): APRIL - JUNI
Publisher : Fakultas Kedokteran Universitas Kristen Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33541/mkvol34iss2pp60

Abstract

Abstract LAM stands for lymphangioleiomyomatosis is a progressive lung disease which affects women of all races. Usually the disease manifested during their reproductive age. Pathologically, it is characterized by the abnormal proliferation of immature smooth muscle-like cells that grow aberrantly in the lung pulmonary airway, parenchyma, lymphatics, and blood vessels. The relentless growth of LAM cells leads to respiratory failure and death. lymphangioleiomyomatosis lesions are generated by the proliferation of LAM cells with mutations of one of the tuberous sclerosis complex (TSC) genes. LAM is a rare disease and often goes misdiagnosed as asthma, emphysema, and pulmonary bronchitis. Recent studies indicate that LAM cells can migrate or metastasize to form new lesions in multiple organs. Although they show amorphologically benign appearance. Scientists estimate that there could be 300000 LAM patients worldwide. Recent progress has been made in understanding more about pathogenesis of LAM and facilitate the identification of potential therapeutic targets, aimed at abrogating the aberrant cellular proliferation characteristic of LAM. Keywords: lymphuugloleiomyomatosis; progressive lung disease; abnormal proliferation; immature smooth muscle-like cells
Oogenesis dan Spermatogenesis Pada Mamalia Yovita Harmiatun
Majalah Kedokteran UKI Vol. 25 No. 2 (2007): APRIL - JUNI
Publisher : Fakultas Kedokteran Universitas Kristen Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33541/mkvol34iss2pp60

Abstract

Abstrak Oogenesis adalah proses pembentukan ovum dari sel benih dalam ovariurn sedangkan spermatogenesis adalah proses pembentukan spermatozoon dalam testis. Pada mamalia terdapat perbedaan utama dalamcara menghasilkan ovum dan spermatozoon melalui proses oogenesis dan spermatogenesis. Pada perempuan, oogonia hanya berproliferasi pada fetus, kernudian rncmasuki meiosis sebelum lahir, danmeiosis tersebut berhenti pada profase meiotic pertama sebagai oosit, dan dapat tetap dalam kondisi seperti itu sampai usia 50 tahun. Oosit individual matang dari stok tersebut diovulasikan dalam selangwaktu tertentu, umumnya satu ovum setiap satu siklus, dimulai pada saat pubertas. Pada laki-Iaki, sangat berbeda, meiosis dan spermatogenesis dimulai pada saat pubertas dan kemudian berlanjut secarakontinu di dalam lapisan epitelial tubulus seminiferus testis. Sel benih yang belum matang atauspermatogonia, yang terletak di sebelah luar dan berdekatan dengan lamina basalis tubulus seminiferus,berproliferasi kontinu melalui mitosis. Beberapa sel tcrsebut berhenti berproliferasi, dan kemudianberdiferensiasi menjadi spermatosit primer. Sel tersebut berada pada stadium profase meiotik pertama,kemudian melanjutkan pembelahan pertama meiosis, dan menghasilkan dua spermatosit sekunder. Duaspermatosit sekunder kemudian memasuki pembelahan meiotik II, dan menghasilkan empat spermatid.Keempat spermatid ini kemudian mengalami diferensiasi morfologis menjadi sperma yang kemudianmasuk ke lumen tubulus seminiferus. Persamaan di antara oogenesis dan spermatogenesis adalah keduanya melibatkan mitosis dan meiosis. Kata kunci: gamet; pembelahan sel: mitosis; meiosis. Abstract Oogenesis is a formation process of female garnets from the female's germ cell in the ovary, whereas spermatogenesis is a formation process of male garnets from the male's germ cell in the testis.Thereis a major difference in the way of mammal producing ovum and spermatozoon. In the human females,the immature germ cells, oogonia proliferate only in the fetus, beginning meiosis before birth. In thefirst meitotic prophase they become oocytes, which they may remain for up to 50 years. Individualoocytes mature from this strictly limited stock and are ovulated at intervals, generally one at a time ora cycle, beginning at puberty. In the contrary, the human male’s meiosis and spermatogenesis do notbegin in the testes until puberty and then go on continuously in the epithelial lining of seminiferoustubules. The immature germ cells, spermatogonia, are located around the outer edge of these tubes next to the basal lamina, where they continuously proliferate by mitosis. Some of these cells stopproliferating and begin to differentiate into primary spermatocytes. These cells begin the first meitoticprophase, and then proceed with the first division of meiosis to produce two secondary spermatocytes. Then the two secondary spermatocytes proceed through the second meiotic division to produce fourspermatids. Finally, the spermatids undergo the morphological differentiation into sperm which escape into the lumen of seminiferous tubule. The similarities between oogenesis and spermatogenesis arethat both have mitosis and meiosis. Key words: gametes; cell division; mitosis; meiosis