Correlation of the chemical structure of 4-nitroquinolines inactivating human cytomegalovirus and established in vivo carcinogenicity tests

Inactivation of the infectivity of human cytomegalovirus (CMV) and herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) has been observed following exposure to 4-nitroquinoline 1-oxide (NQO) or its metabolite, 4-hydroxyaminoquinoline 1-oxide (HAQO). The present study of the specificity of the chemical structure of 4-nitroquinolines demonstrated that both the 4-nitro and 1-oxide groups were required for inactivation of virus infectivity. Reduction of the 4-nitro group to a 4-hydroxyamino group enhanced activity, while further reduction to an amino group resulted in loss of activity against virus infectivity. The capacity to inactivate virus was also lost by substitution of the pyridine ring for the quinoline nucleus of NQO. The relationship between the chemical structure and the ability to inactivate viruses studied here correlates well with earlier in vivo carcinogenicity studies of the same group of chemicals.     

A rare case of primary Ewings sarcoma of the nasal bone

Primary Ewing’s sarcoma of the nasal bone has not been previously described. This case presented as a mass in the left ala of the nose in a five year old female child. The clinical, radiological, microscopic features are described and a review of literature is presented. The case was treated with neoadjuvant chemotherapy and local electron beam radiation therapy. The child was free of disease when she reported for follow up in July 1997. Although wide excision is part of the treatment approach in Ewing’s sarcoma, in sites where surgery is not suitable local radiotherapy and chemotherapy adequately controls primary disease.     

Incomplete hypospadiac urethral duplication with posterior urethral valves

Urethral duplication (UD) is an uncommon malformation. Obstruction rarely occurs in hypospadiac UD. We describe two children with incomplete hypospadiac UD in association with posterior urethral valves, a combination not previously recognised. The embryonic significance of this anomaly is discussed. Accepted: 30 September 1997     

A rare case of primary Ewings sarcoma of the nasal bone

Primary Ewing’s sarcoma of the nasal bone has not been previously described. This case presented as a mass in the left ala of the nose in a five year old female child. The clinical, radiological, microscopic features are described and a review of literature is presented. The case was treated with neoadjuvant chemotherapy and local electron beam radiation therapy. The child was free of disease when she reported for follow up in July 1997. Although wide excision is part of the treatment approach in Ewing’s sarcoma, in sites where surgery is not suitable local radiotherapy and chemotherapy adequately controls primary disease.     

Design and Development of Acetylthiocholine Electrochemical Biosensor Based on Zinc Oxide–Cerium Oxide Nanohybrid Modified Platinum Electrode

Acetylcholinesterase (AChE) enzyme has been predominantly used for the detection of pesticides and metal ions. But, these sensors respond to pesticides as well as metal ions at certain concentration, which results in poor selectivity. Hence in this work, the amount of thiocholine produced during AChE inhibition has been estimated to detect the residual activity of AChE enzyme in-turn to enhance the efficiency of the biosensor. In this context, Pt/ZnO–CeO₂/AChE/Chitosan based biosensor has been developed for sensitive voltammetric quantification of thiocholine in AChE. The sensor exhibited enhanced electron transfer rate, good conductivity and biocompatibility. Both the intrinsic and extrinsic parameters were simultaneously optimized using second order polynomial regression to get the best conditions for ATCh determination. Under optimized experimental conditions, the redox peak current was linear over the concentration range of 0.1–1.5 mM with detection and quantification limit of 0.05 and 0.15 μM respectively and the sensitivity of 1.47 μA mM^?1.     

Study of human papillomavirus infection in patients with anal squamous carcinoma

PURPOSE: The purpose of this study was to determine the incidence of human papillomavirus deoxyribonucleic acid (HPV DNA) in anal squamous carcinoma. METHODS: HPV DNA in situ hybridization for HPV Types 6, 11, 16, 18, 31, 33, and 35 was performed on the formalin-fixed, paraffinembedded tissue from 53 perianal and anal squamous carcinomas and 10 controls. RESULTS: HPV DNA sequences were identified in 18 of 53 anal squamous carcinomas (34 percent). All 10 controls were negative for HPV DNA. Of the 18 positive patients, 10 were perianal squamous carcinomas, and 8 were anal canal squamous carcinomas. Six of the perianal carcinomas were positive for HPV Types 6 and 11. The remaining four perianal carcinomas and all eight of the anal canal carcinomas were positive for HPV Types 16 and 18. CONCLUSION: HPV DNA sequences can be identified in anal squamous carcinomas. Anal squamous epithelium is another site where HPV infection may carry a risk for malignant transformation. One-third of anal squamous carcinomas may be associated with prior HPV infection. Patients with anogenital HPV infection should be routinely screened for anal squamous lesions.     

Perianal abscesses and fistulas

In a five and one-half year period, 1023 patients with anorectal abscesses and fistulas were treated. Under regional anesthesia the abscesses were unroofed and debrided and a primary fistulotomy was performed whenever a low fistula was identified. In 355 (34.7 per cent) an internal fistulous opening was demonstrated at the time of abscess drainage. Thirty-two patients had suprashincteric fistulas and underwent two-stage fistulotomy using a seton. Perianal abscesses were encountered in 42.7 per cent of the patients, followed by ischiorectal (22.7 per cent), intersphincteric (21.4 per cent), and supralevator (7.33 per cent). The patients with supralevator and intersphincteric abscesses had a high incidence of fistula identified during abscess drainage. The recurrence rates were 3.7 per cent in the group with abscess drainage only and 1.8 per cent in the group that had primary fistulotomy along with abscess drainage. The follow-up period averaged 36 months. To accomplish adequate drainage and identify the deeper components and associated fistulous opening (34.7 per cent of the entire group), careful examination under regional anesthesia is recommended. Early aggressive treatment of an anorectal abscess and fistula significantly reduces the possibility of recurrent abscesses and/or the need for further surgery. Read at the meeting of The American Society of Colon and Rectal Surgeons, Boston, Massachusetts, June 5 to 9, 1983. Recipient of the 1983 Rowell Laboratories Education Committee Award.