Quinoxaline and quinoxaline‐1,4‐di‐N‐oxides: An emerging class of antimycobacterials

Tuberculosis (TB) is a highly dreaded, infectious, chronic, airborne disease affecting more than two million people all around the world, with more than eight million cases every calendar year. TB is the second leading infectious cause of death after HIV/AIDS. Over the past few decades, numerous efforts have been undertaken to develop new anti‐TB agents. The current frontline therapy for TB consists of administering three or more different drugs (usually isoniazid, rifampin, pyrazinamide, and ethambutol) over an extended period of time. But these drugs will take 6–12 months to cure TB, along with many side effects; hence, there is an urgent need to explore new anti‐TB agents. Quinoxaline derivatives are a class of compounds that show a spectrum of biological properties and the interest in these compounds is exponentially growing within the field of medicinal chemistry. Quinoxaline‐1,4‐di‐N‐oxide derivatives have shown to improve the biological results and are endowed with anti‐viral, anti‐cancer, anti‐bacterial, and anti‐protozoal activities with application in many other therapeutic areas. Since quinoxaline derivatives are regarded as a new class of effective anti‐TB candidates, their 1,4‐di‐N‐oxide analogues may show promising in vitro and in vivo anti‐TB activities and might be able to prevent the drug resistance to a certain extent. Therefore, the main aim of this review is to focus on important quinoxaline and quinoxaline‐1,4‐di‐N‐oxide analogues that have shown anti‐TB activities, and their structure–activity relationships for designing anti‐TB agents with better efficacies. The present review will be helpful in providing insights for rational designs of more active and less toxic quinoxaline‐based anti‐TB prodrugs.

     

Large focal defect on liver/spleen scan caused by fatty liver and masquerading as neoplasm.

Focal fatty infiltration of the liver may be mistaken for metastatic disease, primary tumor or other space-occupying lesions on CT or ultrasound. Usually, a 99mTc-sulfur colloid scan is sensitive in documenting the presence of Kupffer's cell in such a process. We present a case that was suggestive of focal fatty infiltrate on a CT scan, nondiagnostic on ultrasound, and seen as a large focal defect on the 99mTc-sulfur colloid liver/spleen scan. A 133Xe inhalation study, however, did show uptake in the area of fatty infiltration. A needle biopsy confirmed the diagnosis.     

Combined Procedures with Laparoscopic Cholecystectomy

With advancement in laparoscopic surgery a number of surgical procedures can be performed combined with laparoscopic cholecystectomy in a single surgery. We evaluate the safety & efficacy of such surgeries. A retrospective review of all patients who had undergone combined procedures with laparoscopic cholecystectomy during January 2005 to June 2009 was performed. 3144 laparoscopic cholecystectomies were performed in the period from January 2005 to June 2009. Of these, 401 cases were combined with another procedure. The mean operative time was 80 min (range 50–270 min). The mean hospital stay was 3.2 days (range 1–5 days). The mean no. of days injectable analgesics was required was 2 days (range 1 day–4 days). Combined procedures provide patients with all the benefits of minimal invasive surgery and also give the benefit of single time anaesthesia without adding to post operative morbidity & hospital stay.     

Malignant fibrous histiocytoma metastatic to the thyroid gland

Despite frequent cancer metastases to the thyroid gland demonstrated at autopsy, finding of thyroid metastasis in clinical practice is rare. Malignancies most commonly metastasizing to the thyroid are malignant melanoma and carcinoma of the breast, kidney, and lung. Very little is known about thyroid metastases caused by sarcomas. Of these, malignant fibrous histiocytoma (MFH) is one of the most common in adults, with a high rate of metastases. A case of clinically significant thyroid metastasis from primary MFH involving the thigh visualized on I-123 thyroid imaging is reported.     

Aortic dissection and bicuspid aortic valve: an autopsy study

Medico-legal post-mortems referred to the Department of Pathology, for the histopathological examination, revealed six cases of acute aortic dissection--two in isolation, three in combination with congenital bicuspid aortic valve; and one isolated case of congenital bicuspid aortic valve. One case of isolated aortic dissection was associated with Marfan's syndrome; and one case of aortic dissection with bicuspid aortic valve was associated with polycystic kidneys. History of hypertension could be elicited in two cases. Cystic medial degeneration of aorta was seen in three cases; one of which was associated with Marfan's syndrome. All five cases of aortic dissection belonged to type II of DeBakey classification.