Hepatitis A (topic1)

Hepatitis A, also known as the infectious hepatitis, is an infectious disease of the liver. It is transmitted commonly by contaminated food or water. In a year, about a ten million people in the whole world are infected with the virus. The time between infection and the appearance of the symptoms, which is called the incubation period, is between two and six weeks and the average incubation period is 28 days.

In developing countries, and in regions with poor hygiene standards, the incidence of infection with this virus is high and the illness is mostly contracted in early childhood. The Hepatitis A virus has also been found in taken to study ocean water quality. Hepatitis A infection causes no symptoms in over 90% of these children .

Hepatitis A doesn’t have a chronic stage and will not cause permanent liver damage. After the infection, the white blood cell called a B cell makes antibodies against the hepatitis A virus fight against future infection. The disease can be prevented by vaccination and hepatitis A vaccine has been proved effective in controlling outbreaks worldwide.




Prevention

Hepatitis A can be prevented by using vaccination and good hygiene. Hepatitis A is also one of the main reasons not to surf or go in the ocean after rains in coastal areas that are known to have bad runoff.


Vaccine

The vaccine protects against the virus in more than 90% of cases for about 10 years. The vaccine contains an inactivated Hepatitis A virus providing active immunity against a future infection. The vaccine was first put into place in 1996 for children in high-risk areas, and in 1999 it was given to areas with increasing levels of infection.

The vaccine is given in two doses in the muscle of the upper arm. The first dose provides protection two to four weeks after initial vaccination; the second booster dose, given six to twelve months later, provides protection for up to twenty years.


Symptoms

Early symptoms of hepatitis A are sometimes mistaken for influenza, but some sufferers, mostly children, show no symptoms at all! Symptoms typically appear 2 to 6 weeks, (the incubation period ), after the initial infection.

Symptoms can return over the following 6-9 months which include:

(1) Fatigue
(2) Fever
(3) Abdominal pain
(4) Nausea
(5) Diarrhea
(6) Appetite loss
(7) Depression
(8) Jaundice, a yellowing of the skin or whites of the eyes
(9) Sharp pains in the right-upper quadrant of the abdomen
(10) Weight loss
(11) Itching

References:http://en.wikipedia.org/wiki/Hepatitis_A

Snow leopards (topic2)

Kingdom:Animalia
Phylum:Chordata
Class:Mammalia
Order:Carnivora
Family:Felidae
Subfamily:Pantherinae
Genus:Uncia

Species:U. uncia
Binomial name:Uncia uncia

Description/ Habitat

Snow leopards are a little smaller than big cats like the tiger and lion but both, exhibit a range of sizes, mostly weighing between 27 and 54 kg. The length of their body ranges from about 74–130 cm with a tail of nearly the same length!
Snow leopards have very long and thick fur and their ears are small and rounded, the base color of their body, varies from smokey grey to yellowish tan, with just white underparts. They have dark grey rosettes on their body with small spots of the same colour on their heads and larger spots on their legs and tail.
The snow leopard has a few adaptations that allows it to live in a snowy environment,it has thick long fur and its ears are small and rounded to reduce the amount of heat lost. They have wide feet with fur(fur creates more friction) for walking on snow.

Diet

Snow leopards are meat eaters(carnivores) and actively hunt their prey, but like all cats are opportunistic feeders, eating whatever meat it can find. They are capable of killing animals almost three times their size! It can readily take much smaller prey such as birds.
The diet of the snow leopard varies in where they live in and is dependant on prey availability. Smaller prey consists of marmots, woolly hares, various rodents, and birds such as the snow cock and chukar.
Snow leopards prefer to ambush prey from above and can leap as far as 14 meters.

Breeding

Snow leopards usually mate during late winter and their gestation period is about 90–100 days. Litter sizes vary from one to five cubs but two or three is more usual. The cubs remain with their mother until they become about 18–22 months.
Snow leopards normally live for 15–18 years, but may live for up to 20 years in captivity.

conservation

Due to the high demand for their coats, snow leopards are illegally hunted for the fur trade.







references:http://en.wikipedia.org/wiki/Snow_Leopard

Toxoplasma (topic1)

Toxoplasmosis is a kind of parasitic disease caused by the protozoan called Toxoplasma . The parasite infects warm-blooded animals, which includes humans, but the primary host is the cat family. Animals are infected because of eating infected meat, ingestion of faeces of a cat that has itself recently been infected, or by transmission from mother to baby. Cats have been said to be the major reservoir of this infection. About up to one third of the whole world's population is estimated to carry a Toxoplasma infection.


Symptoms
On the first few weeks, this parasite might cause a mild flu-like illness or no illness. After the first few weeks of infection have passed, the parasite almost never cause any symptoms in healthy people. However, people that have a weak immune system because of HIV or pregnancy, may become seriously ill, and it can be most of the time fatal. The parasite can cause inflammation of the brain and can affect the heart, liver, and eyes.


Diagnosis
Detection of Toxoplasma in human blood samples may be achieved by using the PCR which is polymerase chain reaction. Inactive cysts may exist in a host which would evade detection.


Treatment
Treatment is often only recommended for people with serious health problems, because the disease is most serious when one's immune system is weak.

Medications :
Pyrimethamine — an antimalarial medication.
Sulfadiazine — an antibiotic used in combination with pyrimethamine for treating toxoplasmosis.
clindamycin — an antibiotic. This is used most often for people with HIV/AIDS.


Behavioral changes
It has been found that the parasite has the ability to change the behavior of its host: infected rats and mice are less fearful of cats — in fact, some of the infected rats seek out cat-urine-marked areas. This effect is advantageous to the parasite, which will be able to sexually reproduce if its host is eaten by a cat.

Correlations have been found between latent Toxoplasma infections and various characteristics:

Decreased novelty-seeking behaviour
Slower reactions
Lower rule-consciousness and jealousy (in men)
More warmth and conscientiousness (in women)
Toxoplasmosis




Reference: http://kidshealth.org/parent/infections/parasitic/toxoplasmosis.html

The giant panda (topic2)

Kingdom:Animalia
Phylum:Chordata
Class:Mammalia
Order:Carnivora
Family:Ursidae
Genus:Ailuropoda

Species:A. melanoleuca
Binomial name

Ailuropoda melanoleuca

Physical description

The giant panda, a black-and-white bear, has a body typical of bears. It has black fur on ears, eye patches, legs, and shoulders. The rest of the animal's coat is white. Although scientists do not know why these unusual bears are black and white, it is said that the bold coloring provides effective camouflage into their shade-dappled snowy and rocky surroundings. The panda has a thick, wooly coat which keeps it warm in cool forests of its habitat. Giant pandas have large molar teeth and strong jaw muscles for crushing bamboo which is tough. Many people find these animals to be cute, but in fact, giant pandas can be as dangerous as any other bear. Mature giant pandas is able to reach four to six feet long. Males are always larger than females, weighing up to about 250 pounds in the wild. Females are rarely able to reach 220 pounds. Chinese scientists have reported that zoo pandas as old as 35.





Habitat

Giant pandas live in broadleaf and coniferous forests with a narrow understory of bamboo, at at heights between 5,000 and 10,000 feet.There are torrential rains or dense mist throughout the year so the forest is often shrouded in heavy clouds.





Status

The giant panda is listed as endangered because there are about 1,600 left in the wild. They are threatened because of deforesation which is destroying their habitats.



Diet

A wild giant panda’s diet is 99%(mostly) bamboo. The 1% consists of other grasses and occasional small rodents or musk deer fawns. In zoos, giant pandas eat bamboo, sugar cane, rice gruel, a special high-fiber biscuit, carrots, apples, and sweet potatoes.


The giant panda has lived in bamboo forests for several million years. It is a highly specialized animal, with unique adaptations.




Reproduction

Giant pandas reach breeding maturity between four and eight years of age. They may be reproductive until about age 20. Female pandas ovulate only once a year, in the spring. A short period of two to three days around ovulation is the only time she is able to conceive. Calls and scents draw males and females to each other.

Female giant pandas give birth between 95 and 160 days after mating. Although females may give birth to two young, usually only one survives. Giant panda cubs stay with their mothers from one and a half to three years before striking out on their own. This means a wild female, at best, can produce young only every other year; in her lifetime, she may successfully raise only five to eight cubs. The giant pandas’ naturally slow breeding rate prevents a population from recovering quickly from illegal hunting, habitat loss, and other human-related causes of mortality.



Reference: http://en.wikipedia.org/wiki/Giant_Panda

Trichomoniasis (topic1)

Trichomoniasis is a common cause of vaginitis. It results couples from sharing external water sources like Eg. hot tubs, wet bathing suits, wet towels and so on and so for, since it is a sexually transmitted disease . It is caused by the single-celled protozoan parasite called Trichomonas vaginalis. Trichomoniasis is an infection of the urogenital tract. The most common site of infection is the urethra and the vagina in women. It is more common in women and than uncircumcised men. For these men, the most common site for the infection is at the tip of the penis.



Symptoms include:Vaginitis( itching, burning, and inflammation of the vagina ), Cervicitis which is the inflammation of the cervix,Urethritis the inflammation of the urethra , Greenish Yellow frothy vaginal discharge with a strong odor. Most men with trichomoniasis do not have signs or symptoms, but very few men might have a temporarily irritation inside the penis or mild discharge, or slight burning after urination . In very cases, lower abdominal pain can occur. Symptoms usually appear in women within 5 to 28 days of exposure.


Diagnosis
In women, the doctor will collect a specimen during a pelvic examination, starting by inserting a speculum into the vagina and then using a applicator to collect the sample. The sample would be sent to a labortory for analysis. During the analysis, there might be small red ulcerations on the vaginal wall or cervix.

Treatment
To treat both pregnant and non-pregnant patients, metronidazole (Flagyl) is usually used. The dosage is 500mg oral 2-3 times per day for 7-10 days. Both sexual partners, even if asymptomatic, must be treated at the same time.

References:http://en.wikipedia.org/wiki/Trichomoniasis

The leopard shark (topic2)

The leopard shark, also known as the ‘Triakis semifasciata’ . It can be found along the coast of North America from Oregon to Baja California. This shark is not dangerous to people, though the animal will bite if bothered.

Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Order: Carcharhiniformes
Family: Triakidae
Genus: Triakis
Species: T. semifasciata
Binomial name :Triakis semifasciata




SPECIAL CHARACTERISTICS
The leopard shark can grow up to a maximum of 180 cm in length. It can weigh up to 71 pounds (32 kg) The markings on their backs gave the leopard shark its common name and also provide camouflage.

DIET
Leopard sharks are benthic (bottom-dwelling), which includes worms, mollusks, crustaceans, octopuses, and small fishes.

REPRODUCTION
The leopard shark is ‘ovoviviparous’, which means that the female gives birth to young that is live that has been developed from eggs hatched inside her body ( 4 to 29 pups per litter). Most of the time, the leopard shark’s young are usually born in spring.

PREDATOR
Marine mammals prey upon young leopard sharks, and both juvenile and adults are vulnerable to large fish, including the white shark.

CONSERVATION STATUS
Although it is not really endangered, it still needs people to conserve or protect it

HABITAT
Leopard sharks are found in rocky areas, like rocky reefs or kelp beds. Leopard sharks swim at depths of about 10 to 250 ft. They are mostly seen swimming at 20 feet or less. They prefer cold water more than warm water.

References: http://en.wikipedia.org/wiki/Leopard_Shark

http://www.sdnhm.org/kids/sharks/shore-to-sea/leopard.html

The Naegleria fowleri (topic1)

The Naegleria fowleri which is also known as the brain-eating amoeba, mostly found in warm fresh water, that is around temperatures of 25 to 35 degrees Celsius in either an amoeboid or temporary flagellate stage.(look at the picture above)
The Naegleria fowleri is able to invade the nervous system.Although this occurs rarely, if it attacks the nervous system, resulting the death of the victim.

The Naegaleria fowleri can enter from the nose, and then starts to invade the central nervous system. When the Naegaleria fowleri enters the nose, the amoebae will climb along nerve fibers via the floor of the cranium through the plates of the cribriform and finally into the brain. It then becomes pathogenic, causing primary amoebic meningoencephalitis (PAM or PAME). PAM affects our central nervous system and olfactory perception (taste and smell), followed by vomiting, nausea, fever, headache, and may even result in unconsciousness and death within two weeks.

PAM usually occurs in healthy children or young adults with no prior history of immune compromise who have recently been exposed to bodies of fresh water.

Domain: Eukaryota
(unranked): Excavata
Phylum: Percolozoa
Class: Heterolobosea
Order: Schizopyrenida
Family: Vahlkampfiidae
Genus: Naegleria
Species: N. fowleri
Binomial name
Naegleria fowleri

references:http://en.wikipedia.org/wiki/Naegleria_fowleri