A 12 year old girl complains about abrupt weakness, nausea, dizziness, vision impairment. The day before she ate home-made stockfish, beef. Examination revealed skin pallor, a scratch on the left knee, dryness of mucous membranes of oral pharynx, bilateral ptosis, mydriatic pupils. The girl is unable to read a simple text (mist over the eyes). What therapy would be the most adequate in this case?

Correct Answer: D

Rationale: The correct answer is D: Parenteral introduction of antitetanus serum. The symptoms described in the question, such as bilateral ptosis, mydriatic pupils, and difficulty reading, are indicative of tetanus infection. The source of infection could be the scratch on the knee, which allowed the tetanus bacteria to enter the body. The most appropriate therapy for tetanus is the administration of antitetanus serum to neutralize the tetanus toxin. Antibotulinic serum (choice A) is not appropriate as it is used for botulism, which presents differently. Disintoxication (choice B) is too general and does not address the specific cause of the symptoms. Antibiotics (choice C) are not effective in treating tetanus because it is caused by a toxin, not a bacterial infection. Therefore, the correct course of action is to administer antitetanus serum to the patient.

Correct Answer: B

Rationale: The correct answer is B: Escherichia coli. E. coli is a common bacterium found in the gastrointestinal tract and is a leading cause of UTIs. It has specific virulence factors that enable it to adhere to and infect the urinary tract. Salmonella enterica causes food poisoning, Vibrio cholerae causes cholera, and Streptococcus pyogenes causes strep throat and skin infections, not UTIs. Therefore, B is the correct answer as it is the only bacterium known for causing UTIs.

Correct Answer: A

Rationale: The correct answer is A: Treponema pallidum. This is because Treponema pallidum is a thin spiral bacteria with 12-14 coils and pointed ends, which matches the description given in the question. Treponema pallidum is the causative agent of syphilis. Choices B, C, and D are incorrect: B: Leptospira - Leptospira is a spiral-shaped bacteria, but it does not have the specific characteristics mentioned in the question. C: Borrelia - Borrelia is another spiral-shaped bacteria, but it does not match the specific features described in the question. D: Spirochaeta - Spirochaeta is a genus of spiral-shaped bacteria, but it does not fit the description of having 12-14 coils and pointed ends as mentioned in the question.

Correct Answer: C

Rationale: Step 1: The nucleocapsid is the structure containing the viral genome and the protein capsid. Step 2: The genome carries the genetic material of the virus. Step 3: The capsid is the protein coat that encloses and protects the viral genome. Step 4: Therefore, the correct answer is C: Genome and capsid. Summary: A: Capsid and spikes - Incorrect, spikes are not part of the nucleocapsid. B: Genome and envelop - Incorrect, the envelop is not part of the nucleocapsid. D: Capsid and envelope - Incorrect, the envelope is not part of the nucleocapsid.

Correct Answer: D

Rationale: The correct answer is D, the rabies virus. Rabies virus has the widest infectious spectrum among the given choices because it can infect a wide range of mammals, including humans. This is due to its ability to infect nerve cells and spread throughout the central nervous system. The other choices have more limited infectious spectra. Anthrax bacillus primarily infects herbivores and humans, mumps virus infects mainly humans, and the causative agent of gonorrhea primarily infects humans through sexual contact. Therefore, the rabies virus is the correct answer as it has the broadest range of potential hosts.

Correct Answer: D

Rationale: The correct answer is D: Gram-negative bacteria without peptidoglycan. Chlamydia is an intracellular, gram-negative bacteria that lacks peptidoglycan in its cell wall. Peptidoglycan is a key component of the cell wall in most bacteria, but Chlamydia has a unique structure without it. This makes it different from choices A, B, and C, which describe characteristics not applicable to Chlamydia. Choice A is incorrect because Chlamydia is not a gram-positive coccobacteria. Choice B is incorrect because Chlamydia does have a cell wall, albeit lacking peptidoglycan. Choice C is incorrect because Chlamydia is not a gram-negative bacteria with little peptidoglycan, but rather without it.

Correct Answer: A

Rationale: The correct answer is A: Bacteria. Urinary tract infections (UTIs) are primarily caused by the invasion of bacteria into the urinary tract. Bacteria, especially Escherichia coli (E. coli), are the most common culprits. They enter the urinary tract through the urethra and can multiply in the bladder, leading to infection. Viruses (choice B) and fungi (choice C) are not typical causes of UTIs. "None of the above" (choice D) is incorrect as bacteria are indeed the main cause of UTIs.

Correct Answer: B

Rationale: The correct answer is B: Blood agar. Pneumococci are fastidious bacteria that require enriched media for cultivation. Blood agar provides essential nutrients and growth factors needed for the growth of pneumococci. It contains sheep blood, which provides hemin and NAD, supporting the growth of these bacteria. Kligler iron agar (A) is used for differentiating enteric bacteria based on glucose and lactose fermentation. Apocholate citrate agar (C) is used for the selective isolation of Escherichia coli. Peptone water (D) is a non-selective medium used for the initial cultivation of microorganisms.

Correct Answer: B

Rationale: Step 1: Gram-negative, comma-shaped bacterium suggests a curved rod morphology, typical of Campylobacter jejuni. Step 2: Motility is a characteristic of Campylobacter species. Step 3: Campylobacter jejuni is a common cause of bacterial diarrhea in humans. Step 4: Vibrio cholerae causes cholera, not typically associated with comma-shaped morphology. Shigella dysenteriae and Escherichia coli are not comma-shaped.