Kingdom

Posted by 4rcknight

In biology, kingdom (Latin: regnum, pl. regna) is a taxonomic rank, which is either the highest rank or in the more recent three-domain system, the rank below domain. Kingdoms are divided into smaller groups called phyla (in zoology) or divisions in botany. The complete sequence of ranks is life, domain, kingdom, phylum, class, order, family, genus, and species.
Currently, textbooks from the United States use a system of six kingdoms (Animalia, Plantae, Fungi, Protista, Archaea, Bacteria) while British, Australian and Latin American textbooks may describe five kingdoms (Animalia, Plantae, Fungi, Protista, and Prokaryota or Monera).
Historically, the number of kingdoms in widely accepted classifications has grown from two to six. However, phylogenetic research from about 2000 onwards does not support any of the traditional systems.

Two kingdoms

The classification of living things into animals and plants is an ancient one. Aristotle (384 BC–322 BC) classified animal species in his work the History of Animals, and his pupil Theophrastus (c. 371–c. 287 BC) wrote a parallel work on plants (the History of Plants).
Carolus Linnaeus (1707–1778) laid the foundations for modern biological nomenclature, now regulated by the Nomenclature Codes. He distinguished two kingdoms of living things: Regnum Animale ('animal kingdom') for animals and Regnum Vegetabile ('vegetable kingdom') for plants. (Linnaeus also included minerals, placing them in a third kingdom, Regnum Lapideum.) Linnaeus divided each kingdom into classes, later grouped into phyla for animals and divisions for plants.

life

Regnum Vegetabile


Regnum Animale



Three kingdoms

In 1674, Antonie van Leeuwenhoek, often called the "father of microscopy", sent the Royal Society of London a copy of his first observations of microscopic single-celled organisms. Up to the last few decades, the existence of such microscopic organisms was entirely unknown. At first these organisms were divided into animals and plants and placed in the appropriate Kingdom. However, by the mid-19th century it had become clear that "the existing dichotomy of the plant and animal kingdoms [had become] rapidly blurred at its boundaries and outmoded". In 1866, following earlier proposals by Richard Owen and John Hogg, Ernst Haeckel proposed a third kingdom of life. Haeckel revised the content of this kingdom a number of times before settling on a division based on whether organisms were unicellular (Protista) or multicellular (animals and plants).

life

Kingdom Protista


Kingdom Plantae


Kingdom Animalia



Four kingdoms

The development of microscopy, and the electron microscope in particular, revealed an important distinction between those unicellular organisms whose cells do not have a distinct nucleus, prokaryotes, and those unicellular and multicellular organisms whose cells do have a distinct nucleus, eukaryotes. In 1938, Herbert F. Copeland proposed a four-kingdom classification, moving the two prokaryotic groups, bacteria and "blue-green algae", into a separate Kingdom Monera.

life

Kingdom Monera (prokaryotes, i.e. bacteria and "blue-green algae")


Kingdom Protista (single-celled eukaryotes)


Kingdom Plantae


Kingdom Animalia



It gradually became apparent how important the prokaryote/eukaryote distinction is, and Stanier and van Niel popularized Édouard Chatton's proposal in the 1960s to recognize this division in a formal classification. This required the creation, for the first time, of a rank above kingdom, a superkingdom or empire, also called a domain.

life

Empire Prokaryota Kingdom Protista


Kingdom Plantae


Kingdom Animalia




Five kingdoms

The differences between fungi and other organisms regarded as plants had long been recognized. For example, at one point Haeckel moved the fungi out of Plantae into Protista, before changing his mind. Robert Whittaker recognized an additional kingdom for the Fungi. The resulting five-kingdom system, proposed in 1969 by Whittaker, has become a popular standard and with some refinement is still used in many works and forms the basis for new multi-kingdom systems. It is based mainly on differences in nutrition; his Plantae were mostly multicellular autotrophs, his Animalia multicellular heterotrophs, and his Fungi multicellular saprotrophs. The remaining two kingdoms, Protista and Monera, included unicellular and simple cellular colonies. The five kingdom system may be combined with the two empire system.

life

Empire Prokaryota

Kingdom Monera




Empire Eukaryota

Kingdom Protista


Kingdom Plantae


Kingdom Fungi


Kingdom Animalia





Six kingdoms

From around the mid-1970s onwards, there was an increasing emphasis on molecular level comparisons of genes (initially ribosomal RNA genes) as the primary factor in classification; genetic similarity was stressed over outward appearances and behavior. Taxonomic ranks, including kingdoms, were to be groups of organisms with a common ancestor, whether monophyletic (all descendants of a common ancestor) or paraphyletic (only some descendants of a common ancestor). Based on such RNA studies, Carl Woese divided the prokaryotes (Kingdom Monera) into two groups, called Eubacteria and Archaebacteria, stressing that there was as much genetic difference between these two groups as between either of them and all eukaryotes. Eukaryote groups, such as plants, fungi and animals may look different, but are more similar to each other in their genetic makeup at the molecular level than they are to either the Eubacteria or Archaebacteria. (It was also found that the eukaryotes are more closely related, genetically, to the Archaebacteria than they are to the Eubacteria.) Although the primacy of the eubacteria-archaebacteria divide has been questioned, it has also been upheld by subsequent research.
Woese attempted to establish a "three primary kingdom" or "urkingdom" system. In 1990, the name "domain" was proposed for the highest rank. The six-kingdom system shown below represents a blending of the classic five-kingdom system and Woese's three-domain system. Such six-kingdom systems have become standard in many works.

life

Domain Bacteria

Kingdom Bacteria




Domain Archaea

Kingdom Archaea




Domain Eukarya

Kingdom Protista


Kingdom Plantae


Kingdom Fungi


Kingdom Animalia





Woese also recognized that the Protista kingdom was not a monophyletic group and might be further divided at the level of kingdom.

Cavalier-Smith's six kingdoms

Thomas Cavalier-Smith has published extensively on the evolution and classification of life, particularly protists. His views have been influential but controversial, and not always widely accepted. In 1998, he published a six-kingdom model, which has been revised in subsequent papers. The version published in 2009 is shown below. (Compared to the version he published in 2004, the alveolates and the rhizarians have been moved from Kingdom Protozoa to Kingdom Chromista.) Cavalier-Smith does not accept the importance of the fundamental eubacteria–archaebacteria divide put forward by Woese and others and supported by recent research. His Kingdom Bacteria includes the Archaebacteria as part of a subkingdom along with a group of eubacteria (Posibacteria). Nor does he accept the requirement for groups to be monophyletic. His Kingdom Protozoa includes the ancestors of Animalia and Fungi. Thus the diagram below does not represent an evolutionary tree.

life

Empire Prokaryota

Kingdom Bacteria — includes Archaebacteria as part of a subkingdom




Empire Eukaryota

Kingdom Protozoa — e.g. Amoebozoa, Choanozoa, Excavata


Kingdom Chromista — e.g. Alveolata, cryptophytes, Heterokonta (stramenopiles), Haptophyta, Rhizaria


Kingdom Plantae — e.g. glaucophytes, red and green algae, land plants


Kingdom Fungi


Kingdom Animalia





International Society of Protistologists Classification 2005

One hypothesis of eukaryotic relationships, modified from Simpson and Roger (2004).
The "classic" six-kingdom system is still recognizably a modification of the original two-kingdom system: Animalia remains; the original category of plants has been split into Plantae and Fungi; and single-celled organisms have been introduced and split into Bacteria, Archaea and Protista.
Research published in the 21st century has produced a rather different picture. In 2004, a review article by Simpson and Roger noted that the Protista were "a grab-bag for all eukaryotes that are not animals, plants or fungi". They argued that only monophyletic groups–an ancestor and all of its descendents — should be accepted as formal ranks in a classification. On this basis, the diagram opposite (redrawn from their article) showed the real "kingdoms" (their quotation marks) of the eukaryotes. A classification produced in 2005 for the International Society of Protistologists, which reflected the consensus of the time[citation needed], followed this approach, dividing the eukaryotes into the same six "supergroups". Although the published classification deliberately did not use formal taxonomic ranks, other sources[citation needed] have treated each of the six as a separate Kingdom.

life

Domain Bacteria

Bacteria




Domain Archaea

Archaea




Domain Eukarya

Excavata — Various flagellate protozoa


Amoebozoa — most lobose amoeboids and slime moulds


Opisthokontaanimals, fungi, choanoflagellates, etc.


RhizariaForaminifera, Radiolaria, and various other amoeboid protozoa


ChromalveolataStramenopiles (or Heterokonta), Haptophyta, Cryptophyta (or cryptomonads), and Alveolata


Archaeplastida (or Primoplantae) — Land plants, green algae, red algae, and glaucophytes





In this system, the traditional kingdoms have vanished. For example, research shows that the multicellular animals (Metazoa) are descended from the same ancestor as the unicellular choanoflagellates and the fungi. A classification system which places these three groups into different kingdoms (with multicellular animals forming Animalia, choanoflagellates part of Protista and Fungi a separate kingdom) is not monophyletic. The monophyletic group is the Opisthokonta, made up of all those organisms believed to have descended from a common ancestor, some of which are unicellular (choanoflagellates), some of which are multicellular but not closely related to animals (some fungi), and others of which are traditional multicellular animals.
However, in the same year as the International Society of Protistologists' classification was published (2005), doubts were being expressed as to whether some of these supergroups were monophyletic, particularly the Chromalveolata, and a review in 2006 noted the lack of evidence for several of the supposed six supergroups.
As of 2010, there is widespread agreement that the Rhizaria belong with the Stramenopiles and the Alveolata, in a clade dubbed the SAR supergroup[citation needed], so that Rhizara is not one of the main eukaryote groups. Beyond this, there does not appear to be a consensus. Rogozin et al. in 2009 noted that "The deep phylogeny of eukaryotes is an extremely difficult and controversial problem."[20] As of December 2010, there appears to be a consensus that the 2005 six supergroup model does not reflect the true phylogeny of the eukaryotes and hence how they should be classified, although there is no agreement as to the model which should replace it.

Summary

The sequence from the two-kingdom system up to Cavalier-Smith's six-kingdom system can be summarized in the table below.
Linnaeus
1735[23]
2 kingdoms
Haeckel
1866[24]
3 kingdoms
Chatton
1925[25][26]
2 empires
Copeland
1938[27][28]
4 kingdoms
Whittaker
1969[4]
5 kingdoms
Woese et al.
1977[6][29]
6 kingdoms
Woese et al.
1990[30]
3 domains
Cavalier-Smith
2004[11]
6 kingdoms
(not treated) Protista Prokaryota Mychota Monera Eubacteria Bacteria Bacteria
Archaebacteria Archaea
Eukaryota Protoctista Protista Protista Eukarya Protozoa
Chromista
Vegetabilia Plantae Plantae Plantae Plantae Plantae
Protoctista Fungi Fungi Fungi
Animalia Animalia Animalia Animalia Animalia Animalia
Note that the equivalences in this table are not perfect. For example, Haeckel placed the red algae (his Florideae, modern Florideophyceae) and blue-green algae (his Archephyta, modern Cyanobacteria) in his Plantae.
One or other of the kingdom-level classifications of life is still widely employed as a useful way of grouping organisms, notwithstanding the problems with this approach:
  • Kingdoms such as Bacteria represent grades rather than clades, and so are rejected by phylogenetic classification systems.
  • Research in the 21st century does not support the classification of the eukaryotes into any of the standard systems. As of April 2010, the situation appears to be that there is no set of kingdoms sufficiently supported by current research to gain widespread acceptance; as Roger & Simpson say: "with the current pace of change in our understanding of the eukaryote tree of life, we should proceed with caution.

Trachoma

Posted by 4rcknight

Penyebab
Trachoma disebabkan oleh Chlamydia trachomatis dan disebarkan melalui kontak langsung dengan mata, hidung, dan tenggorokan yang terkena cairan (yang mengandung kuman ini) dari pengidap, atau kontak dengan benda mati, seperti handuk dan / atau kain lap, yang pernah kontak serupa dengan cairan ini. Lalat juga dapat menjadi rute transmisi. Jika tidak diobati, infeksi trachoma berulang dapat mengakibatkan  entropion yang merupakan bentuk kebutaan permanen dan disertai rasa nyeri jika kelopak mata berbalik ke dalam, karena ini menyebabkan bulu mata menggaruk kornea. Anak-anak yang paling rentan terhadap infeksi ini karena kecenderungan mereka untuk dengan mudah menjadi kotor, tetapi efek-efek pengihatan kabur dan gejala lebih parah lainnya sering tidak terasa sampai dewasa.
Tanda dan gejala
Bakteri ini memiliki masa inkubasi dari 5 sampai 12 hari setelah seseorang mengalami gejala konjungtivitis atau iritasi mirip dengan “mata merah muda.” Endemik kebutaan trakoma merupakan hasil dari beberapa episode reinfeksi yang menghasilkan peradangan terus-menerus pada konjungtiva. Tanpa reinfeksi, peradangan akan berangsur-angsur mereda.
Peradangan konjunctiva  disebut “trachoma aktif” dan biasanya terlihat pada anak-anak, terutama anak-anak pra sekolah (dasar). Hal ini ditandai dengan benjolan putih di permukaan bawah tutup mata atas (conjunctival folikel atau pusat-pusat germinal limfoid). Non-peradangan dan penebalan tertentu sering dikaitkan dengan papila. Folikel mungkin juga muncul di persimpangan kornea dan sclera (limbal folikel). Trakoma aktif akan sering menjengkelkan dan memiliki cairan berair. Infeksi sekunder bakteri dapat terjadi dan menyebabkan discharge purulen.
Perubahan-perubahan struktural trakoma disebut sebagai “cicatricial trakoma”. Ini termasuk jaringan parut di tutup mata (konjungtiva tarsal) yang mengarah pada distorsi tutup mata dengan tekuk dari tutup (Tarsus) sehingga muncul bulu mata gosok pada mata (trichiasis). Bulu mata ini akan mengakibatkan kekeruhan kornea dan bekas luka dan kemudian mengarah ke kebutaan. Bekas luka linear hadir dalam sulkus subtarsalis disebut ‘garis Arlt’s’. Selain itu, pembuluh darah dan jaringan parut dapat menyerang bagian atas kornea (pannus).
Lebih lanjut gejala termasuk:
  1. Keluarnya cairan kotor dari mata – bukan air mata (emisi atau sekresi cairan yang mengandung lendir dan nanah dari mata)
  2. Pembengkakan kelopak mata
  3. Trichiasis (berbalik-nya bulu mata)
  4. Pembengkakan kelenjar getah bening di depan telinga
  5. Munculnya garis parutan pada kornea
  6. Komplikasi pada telinga, hidung dan tenggorokan.
Komplikasi utama atau yang paling penting adalah ulkus (luka/iritasi) pada kornea karena infeksi bakteri.
Pencegahan dan pengobatan/perawatan
Meskipun trakoma dihapuskan dari banyak negara maju dalam abad terakhir, penyakit ini bertahan di banyak bagian dunia berkembang khususnya di masyarakat tanpa akses yang memadai terhadap air dan sanitasi. Dalam banyak masyarakat ini, wanita tiga kali lebih besar daripada laki-laki akan dibutakan oleh penyakit ini,karena peran mereka sebagai pengasuh dalam keluarga.
Tanpa intervensi, trakoma keluarga tetap bertahan dalam lingkaran kemiskinan, karena penyakit dan efek jangka panjang diwariskan dari satu generasi ke generasi berikutnya.
Pencegahan yang penting meliputi:
  • Pembedahan: Bagi individu dengan trichiasis (berbaliknya arah lengkungan bulu mata ke arah dalam), sebuah prosedur rotasi bilamellar tarsal dibenarkan untuk mengarahkan bulu mata menjauh dari bola mata.
  • Terapi antibiotik: Pedoman WHO merekomendasikan jika terjadi endemik massa (sekitar 10 % dari populasi suatu daerah) maka perawatan/pengobatan dengan antibiotik tahunan harus terus dilakukan sampai prevalensi turun di bawah lima persen. Jika prevalensi lebih rendah dari itu maka pengobatan antibiotik harus berbasiskan keluarga.
  • Pilihan antibiotik: oral dosis tunggal 20 mg / kg atau topical tetracycline (satu persen salep mata dua kali sehari selama enam minggu). Azitromisin lebih disukai karena digunakan sebagai oral dosis tunggal.
  • Kebersihan: Anak-anak dengan hidung terlihat terlalu berair, okular discharge, atau lalat di wajah mereka paling tidak dua kali lebih mungkin untuk memiliki trakoma aktif dibanding anak-anak dengan wajah yang bersih. Intensif kesehatan berbasis masyarakat untuk mempromosikan program pendidikan muka-cuci dapat secara signifikan mengurangi prevalensi trachoma aktif.
  • Perbaikan lingkungan: Modifikasi dalam penggunaan air, kontrol lalat, penggunaan jamban, pendidikan kesehatan dan kedekatan dengan hewan peliharaan semuanya telah diusulkan untuk mengurangi penularan dari C. trachomatis. Perubahan-perubahan ini menimbulkan banyak tantangan untuk pelaksanaannya. Agaknya perubahan lingkungan ini pada akhirnya berdampak pada penularan infeksi okular melalui wajah kurangnya kebersihan.
Prognosis
Jika tidak diobati dengan baik dengan antibiotik oral, gejalanya dapat meningkat dan menyebabkan kebutaan, yang merupakan hasil dari ulkus (luka/iritasi) dan jaringan parut pada kornea. Operasi juga mungkin diperlukan untuk memperbaiki kelainan bentuk kelopak mata.


Filariasis (Kaki Gajah)

Posted by 4rcknight

F I L A R I A S I S

Filariasis adalah penyakit menular ( Penyakit Kaki Gajah ) yang disebabkan oleh cacing Filaria yang ditularkan oleh berbagai jenis nyamuk. Penyakit ini bersifat menahun ( kronis ) dan bila tidak mendapatkan pengobatan dapat menimbulkan cacat menetap berupa pembesaran kaki, lengan dan alat kelamin baik perempuan maupun laki-laki. Akibatnya penderita tidak dapat bekerja secara optimal bahkan hidupnya tergantung kepada orang lain sehingga memnjadi beban keluarga, masyarakat dan negara. Di Indonesia penyakit Kaki Gajah tersebar luas hampir di Seluruh propinsi. Berdasarkan laporan dari hasil survei pada tahun 2000 yang lalu tercatat sebanyak 1553 desa di 647 Puskesmas tersebar di 231 Kabupaten 26 Propinsi sebagai lokasi yang endemis, dengan jumlah kasus kronis 6233 orang. Hasil survai laboratorium, melalui pemeriksaan darah jari, rata-rata Mikrofilaria rate (Mf rate) 3,1 %, berarti sekitar 6 juta orang sudah terinfeksi cacing filaria dan sekitar 100 juta orang mempunyai resiko tinggi untuk ketularan karena nyamuk penularnya tersebar luas. Untuk memberantas penyakit ini sampai tuntas








WHO sudah menetapkan Kesepakatan Global ( The Global Goal of Elimination of Lymphatic Filariasis as a Public Health problem by The Year 2020 (. Program eliminasi dilaksanakan melalui pengobatan missal dengan DEC dan Albendazol setahun sekali selama 5 tahun dilokasi yang endemis dan perawatan kasus klinis baik yang akut maupun kronis untuk mencegah kecacatan dan mengurangi penderitanya. Indonesia akan melaksanakan eliminasi penyakit kaki gajah secara bertahap dimulai pada tahun 2002 di 5 kabupaten percontohan. Perluasan wilayah akan dilaksanakan setiap tahun. Penyebab penyakit kaki gajah adalah tiga spesies cacing filarial yaitu; Wucheria bancrofti, Brugia malayi dan Brugia timori. Vektor penular : Di Indonesia hingga saat ini telah diketahui ada 23 spesies nyamuk dari genus Anopheles, Culex, Mansonia, Aedes & Armigeres yang dapat berperan sebagai vector penular penyakit kaki gajah.

Cara Penularan :
Seseorang dapat tertular atau terinfeksi penyakit kaki gajah apabila orang tersebut digigit nyamuk yang infektif yaitu nyamuk yang mengandung larva stadium III ( L3 ). Nyamuk tersebut mendapat cacing filarial kecil ( mikrofilaria ) sewaktu menghisap darah penderita mengandung microfilaria atau binatang reservoir yang mengandung microfilaria. Siklus Penularan penyakit kaiki gajah ini melalui dua tahap, yaitu perkembangan dalam tubuh nyamuk ( vector ) dan tahap kedua perkembangan dalam tubuh manusia (hospes) dan reservoair.
Gejala klinis Filariais Akut adalah berupa ; Demam berulang-ulang selama 3/a5 hari, Demam dapat hilang bila istirahat dan muncul lagi setelah bekerja berat ; pembengkakan kelenjar getah bening (tanpa ada luka) didaerah lipatan paha, ketiap (lymphadenitis) yang tampak kemerahan, panas dan sakit ; radang saluran kelenjar getah bening yang terasa panas dan sakit yang menjalar dari pangkal kaki atau pangkal lengan kearah ujung (retrograde lymphangitis) ; filarial abses akibat seringnya menderita pembengkakan kelenjar getah bening, dapat pecah dan mengeluarkan nanah serta darah ; pembesaran tungkai, lengan, buah dada, buah zakar yang terlihat agak kemerahan dan terasa panas (early lymphodema). Gejal klinis yang kronis ; berupa pembesaran yang menetap (elephantiasis) pada tungkai, lengan, buah dada, buah zakar (elephantiasis skroti).

Diagnosis
Filariasis dapat ditegakkan secara Klinis ; yaitu bila seseorang tersangka Filariasis ditemukan tanda-tanda dan gejala akut ataupun kronis ; dengan pemeriksaan darah jari yang dilakukan mulai pukul 20.00 malam waktu setempat, seseorang dinyatakan sebagai penderita Filariasis, apabila dalam sediaan darah tebal ditemukan mikrofilaria. Pencegahan ; adalah dengan berusaha menghindarkan diri dari gigitan nyamuk vector ( mengurangi kontak dengan vector) misalnya dengan menggunakan kelambu bula akan sewaktu tidur, menutup ventilasi rumah dengan kasa nyamuk, menggunakan obat nyamuk semprot atau obat nyamuk baker, mengoles kulit dengan obat anti nyamuk, atau dengan cara memberantas nyamuk ; dengan membersihkan tanaman air pada rawa-rawa yang merupakan tempat perindukan nyamuk, menimbun, mengeringkan atau mengalirkan genangan air sebagai tempat perindukan nyamuk ; membersihkan semak-semak disekitar rumah.



 

Pengobatan :
secara massal dilakukan didaeah endemis dengan menggunakan obat Diethyl Carbamazine Citrate (DEC) dikombinasikan dengan Albenzol sekali setahun selama 5/10 tahun, untuk mencegah reaksi samping seperti demam, diberikan Parasetamol ; dosis obat untuk sekali minum adalah, DEC 6 mg/kg/berat badan, Albenzol 400 mg albenzol (1 tablet ) ; pengobatan missal dihentikan apabila Mf rate sudah mencapai < 1 % ; secara individual / selektif; dilakukan pada kasus klinis, baik stadium dini maupun stadium lanjut, jenis dan obat tergantung dari keadaan kasus.