Urinalysis of a patient with acute cystitis shows leukocytes and a large number of gram-negative bacilli. Inoculation has resulted in the growth of mucous colonies that produce a green soluble pigment. What microorganism is the most likely cause of the patient's disorder?

Correct Answer: C

Rationale: The correct answer is C: Escherichia coli. E. coli is the most common cause of acute cystitis. It typically presents with leukocytes and gram-negative bacilli in the urine. The green pigment production indicates pyocyanin, which is a characteristic of E. coli. Pseudomonas aeruginosa (A) can also produce green pigment, but it is less common in urinary tract infections. Proteus mirabilis (B) is associated with a swarming motility pattern on agar, not mucous colonies. Klebsiella pneumoniae (D) is associated with pneumonia and other respiratory infections, not cystitis.

Correct Answer: B

Rationale: The correct answer is B: Diarrhea. Brucellosis typically presents with symptoms such as arthralgia, headache, and undulating fever, but diarrhea is not a common symptom associated with the disease. Brucellosis is primarily characterized by systemic symptoms like fever, joint pain, and headache due to the bacterial infection. Diarrhea is more commonly seen in gastrointestinal infections rather than brucellosis. Therefore, the absence of diarrhea as a symptom in brucellosis helps in differentiating it from other diseases with similar clinical presentations.

Correct Answer: A

Rationale: Step-by-step rationale: 1. Gram-positive diplococci with pointed ends indicate Streptococcus pneumoniae. 2. Presence of capsules supports the likelihood of S. pneumoniae. 3. S. pneumoniae is a common cause of pneumonia. 4. Klebsiella pneumoniae is Gram-negative and does not form diplococci. 5. Neisseria meningitidis typically causes meningitis, not pneumonia. 6. Staphylococcus aureus is Gram-positive but does not typically present as diplococci in pneumonia cases.

Correct Answer: B

Rationale: The correct answer is B: Hepatitis B virus. This is because Hepatitis B virus is a DNA virus, not an RNA virus. The other choices, A (Hepatitis G virus), C (Hepatitis A virus), and D (Hepatitis E virus) are all RNA viruses. Hepatitis B virus is unique as it contains partially double-stranded DNA. DNA viruses replicate through a DNA intermediate, unlike RNA viruses which directly use RNA. Therefore, Hepatitis B virus stands out as the only DNA virus among the given options.

Correct Answer: C

Rationale: The correct answer is C: Escherichia coli. E. coli is the most common cause of acute cystitis. It typically presents with leukocytes and gram-negative bacilli in the urine. The green pigment production indicates pyocyanin, which is a characteristic of E. coli. Pseudomonas aeruginosa (A) can also produce green pigment, but it is less common in urinary tract infections. Proteus mirabilis (B) is associated with a swarming motility pattern on agar, not mucous colonies. Klebsiella pneumoniae (D) is associated with pneumonia and other respiratory infections, not cystitis.

Correct Answer: A

Rationale: The correct answer is A because it accurately describes the major morphological forms of bacteria. Cocci are spherical, rod-shaped bacteria are called bacilli, and curved bacteria are spirilla. Staphylococci, streptococci, and diplococci are specific types of cocci, not major morphological forms. Basicili and spiralis are not common morphological forms of bacteria. Option D is incorrect as the other choices do represent major morphological forms of bacteria.

Correct Answer: A

Rationale: The correct answer is A: tRNA. Anticodons are sequences of nucleotides found on tRNA molecules that complement the codons on mRNA during translation. tRNA molecules carry specific amino acids to the ribosome based on the codon-anticodon pairing. Option B, rRNA, forms the structure of the ribosome and is not directly involved in anticodon recognition. Option C, mRNA, contains codons but not anticodons. Option D, ribosomes, are the site of protein synthesis but do not contain the anticodons themselves.

Correct Answer: C

Rationale: Step 1: Antitetanus serum is crucial for patients with open maxillofacial trauma to prevent tetanus infection from contaminated wounds. Step 2: Antibiotics are needed to prevent infection in the wound. Step 3: Antitetanus serum provides immediate passive immunity while antibiotics help combat potential infections. Step 4: Antitetanus immunoglobulin is not mentioned in the question and is not typically used for prophylaxis. Step 5: Anticonvulsive drugs are not preventive medications for maxillofacial trauma. Step 6: Diphtheria, tetanus, and pertussis vaccines are not specifically indicated for immediate prevention in this scenario.

Correct Answer: A

Rationale: The correct answer is A: Sandfly. Cutaneous leishmaniasis is transmitted by the bite of infected sandflies. These tiny insects are known vectors for Leishmania parasites. Sandflies are active during dusk and night, feeding on blood from mammals, including humans. Tick (B), mosquito (C), and tsetse fly (D) are not vectors for Leishmania parasites. Ticks transmit diseases like Lyme disease, mosquitoes transmit diseases like malaria, and tsetse flies transmit African trypanosomiasis. Therefore, the correct vector for cutaneous leishmaniasis is the sandfly due to its specific role in transmitting the Leishmania parasite.