Etiologic agents of the diseases that we work in our research group

 

Etiologic agent is defined as the agent causing or responsible for a disease, for example a bacterium, virus, fungus, protozoan, etc.

Tuberculosis

 The etiologic agent is Mycobacterium tuberculosis

The etiologic agent is Mycobacterium tuberculosis

 Classification of bacteria due to their cell wall

Classification of bacteria due to their cell wall

 Constituents of Mycobacterium tuberculosis seen by electron microscopy

Constituents of Mycobacterium tuberculosis seen by electron microscopy

 Cell wall of Mycobacterium tuberculosis amplified numerous times by electron microscopy

Cell wall of Mycobacterium tuberculosis amplified numerous times by electron microscopy

tuberculose-img-ttc

Tuberculosis (TB) is an infectious-contagious disease transmitted primarily by air and can reach all organs of the body, but as the bacterium reproduces and develops rapidly in areas of the body with much oxygen, the lung is the main organ struck by disease.

 The sneezing or coughing of an infected person throws in the air about two million bacilli that remain in suspension for hours

The sneezing or coughing of an infected person throws in the air about two million bacilli that remain in suspension for hours

PROBLEM OF MODERN BACTERIAL RESISTANCE

  • tuberculose-img-remedioOf the 100 million annual prescriptions (14 tonnes), 50% are unnecessary.
  • About 60% of the antibiotics used in the USA are used in agriculture (20 tons / year).
  • Currently, about 70% of the bacteria responsible for hospital infections are resistant to at least one commonly used drug.
  • Market that moves around 25 billion dollars.

Malaria

Infections disease transmitted by the bite of female mosquitoes of the genus Anopheles and caused by parasitic protozoa of the genus Plasmodium. Its mais symptoms are fever, headache, and joint pain that can progress to coma or death.

Drugs used to treat malaria

Aminoquinolines

 

Sesquiterpenic lactones

Others

Cancer

Cancer is a set of diseases caused by the abnormal proliferation of cells, thus forming tumors. There are over one hundred types of cancer. Cancer of the skin, lung, breast, liver, stomach, kidney, ovary, brain, prostate, pancreas and bones are some examples. This name is given to all forms of malignant tumors, being its original word of the Latin “cancer”, that means crab. This is due to the similarity between the legs of the crustacean and the tentacles of the tumor, which seep into the healthy tissues of the body

 Cell division of a cancer cell

Cell division of a cancer cell

Lung cancer

Types of cancer

The different types of cancer correspond to the various types of cells of the body, for example, there are several types of skin cancer because the skin is formed of more than one type of cell. If the cancer starts in epithelial tissues such as skin or mucous membranes it is called carcinoma. If cancer starts in connective tissues such as bone, muscle or cartilage is called sarcoma, tumors in the lymphatic system lymphomas and cancer in blood tissue leukemia. Other characteristics that differentiate the different types of cancer among themselves are the speed of multiplication of the cells and the ability to invade neighboring or distant tissues and organs (metastases)

Treatment of cancer

SURGERY
It is the oldest and most definitive, when the tumor is located, under favorable anatomical circumstances. In general it is the most important treatment, which influences more on the cure of the patient. For some types of cancer, however, only surgery is not enough due to the spread of cancerous cells locally or diffusely.

RADIOTHERAPY
It is most commonly used for localized tumors that can not be completely resected, or for tumors that usually reappear locally after surgery.

HORMONOTHERAPY
Sexual hormones are of great importance in Oncology, being deeply involved in the development of various malignant tumors. Due to the high degree of dependence that these tumors usually maintain in relation to the hormones, the blockade to the hormonal action allows to inhibit its growth

 

CHEMOTHERAPY

It is the systemic treatment for cancer. It consists of the use of drugs that have cytotoxic action (causes damages to the cells). These drugs can be administered alone (mono-chemotherapy) or combined (polychemotherapy), the latter having the most effective results, as it achieves greater response to each application, decreasing the risk of drug resistance and reaching the cells at different stages of their cycle.

History of Chemotherapy in Combating Cancer

1942 – Onset of Chemotherapy in the Fight against Cancer.

cancer-historia

1950 – National Cancer Institute (NCI) plays a key role in the development of anti-cancer drugs.

1970 – Under Nixon government this disease received special attention, being responsible for the discovery of important drugs.

Antitumor Antibiotics

 

The importance of taxol as a medicine

1960 – 1981: 110,000 Compounds were evaluated from 35,000 different species, with Taxol being the most promising.
PROBLEM: In order to have 1 kg of Taxol, it takes 10,000 kg of the bark of Taxus brevifolia about 3,000 trees (which take from 100 to 200 years to reach adulthood) and is able to treat only 500 patients in a year.

 

A solution emerges

 1 kg de 10-Desacetilbacatina-III – 3.000 Kg de folhas da Taxus baccata .

1 kg de 10-Desacetilbacatina-III – 3.000 Kg de folhas da Taxus baccata .

Taxol Hemisynthesis

Holton and collaborators

Bristol-Mayer

Robert A. Holton
Bristol-Mayer Squibb Company, New York N.Y.
Paclitaxel, Intaxel, Anzatax, Paxene, Taxol and Yewtaxan

Structure-activity relationship of taxol

1985: Potier et Collaborators Gif-sur-Yvette – France

1994: Rhône-Poulenc Rorer S.A. (Docetaxel)

Leishmaniasis

Leishmaniasis is a disease caused by flagellated protozoa of the genus Leishmania of the family Trypanosomatidae and can be cutaneous or visceral. Nowadays there are 7 species of Leishmania responsible for the disease in the human species and more than 200 species of mosquitoes (phlebotomus) responsible for its transmission. Treatment in humans is based on drugs containing antimony (pentavalent antimonials), pentamidine, miltefosine and amphotericin B.

 Mosquito of the genus Phlebotomus

Mosquito of the genus Phlebotomus

 Leishmania donovani

Leishmania donovani

 Clinical aspect of cutaneous Leishmaniasis

Clinical aspect of cutaneous Leishmaniasis

 Disease life cycle

Disease life cycle