cDNA coding for Brugia malayi pepsin inhibitor homolog (Bm-33) from the human filarial parasite was cloned in pRSET for large-scale expression and functional characterization. The pRSET-B cloned gene did not yield recombinant protein expression and the reason was attributed to the presence of an N-terminal signal peptide. The gene was subcloned in pRSET-A without a signal peptide and the 33 kDa histidine-tagged recombinant protein was purified by IMAC. All individuals from an endemic area generated IgG responses against Bm-33 in the order MF>CP>EN. Isotype analysis indicated an elevated IgG4 reactivity in the order MF>EN>CP. Bm-33-specific IgE levels were elevated in MF, CP and EN compared to non-endemic normals with no significant differences among the groups. Paraffinembedded sections of Setaria digitata (cattle filarial parasite) stained with mouse anti-Bm-33 antibodies exhibited the hypodermal nature of Bm-33. These findings suggest that Bm-33 is an immunodominant antigen and contributes to filarial pathogenesis. Key words antibody, Brugia malayi, ELISA, immunolocalization, isotype.Human lymphatic filariasis is caused by lymph-dwelling, parasitic nematodes such as Wuchereria bancrofti, Brugia malayi and Brugia timori which are prevalent in tropical and subtropical countries of the world. The initiatives of the Filarial Genome Project to combat this nematode scourge have enabled the identification and characterization of genes with diagnostic and prophylactic capabilities such as WbSXP-1, Bm-ALT etc. (1, 2). Despite these and a few more, there is an urgent need to identify and characterize more antigens involved in parasite-specific immune modulation, a major factor that contributes to filarial pathogenesis.The cDNA coding for B. malayi, pepsin inhibitor homolog (Bm-33), a 33 kDa protein (3, 4), was cloned Correspondence Rangarajan B. Narayanan, Centre For Biotechnology, Anna University, Chennai-600 025, Tamil Nadu, India. Tel: +91 044 22350772; fax: +91 044 22350299; email: rbn@annauniv.edu List of Abbreviations ALP, alkaline phosphatase; anti-BmA, antibodies against Brugia malayi crude protein; BCIP, bromochloroindoloyl phosphate; CP, chronic pathology; DAB, diaminobenzidine; EN, endemic normal; HLA, human leukocyte antigen; HRP, horseradish peroxidase; IgG, immunoglobulin G; IMAC, immobilized metal affinity chromatography; IPTG, isopropyl beta thiogalactosidase; MF, microfilaremic; NBT, nitroblue tetrazolium; NEN, non-endemic normal; pNPP, para nitrophenol phosphate. and serologically characterized. Earlier, a similar homolog from Onchocerca volvulus (Ov33) was cloned in pGEX-2T and the GST tagged-recombinant protein was used for immunodiagnosis based on its elevated IgG4 reactivity in microfilaremic patients (5, 6). Homologs were also identified from related parasites such as Dirofilaria immitis and Acanthocheilonema viteae and the respective recombinant proteins (Di33 and Av33) were used for the development of immunodiagnostic assays (7,8). In the case of the Brugian homolog, the 750 bp cDNA cod...

Thyroglossal duct cysts are the most common congenital abnormalities of the neck, constituting about 70% of all cervical neck masses in children and 7% of the adult population. The occurrence of carcinoma in a thyroglossal duct cyst is very rare (less than 1%). Malignancy of the thyroglossal duct cyst usually presents in the third or fourth decade of life. We report a case of carcinoma in the thyroglossal duct cyst, which presented for the first time in our elderly patient. A 76-year-old male presented with a 6 x 5 cm swelling in the anterior aspect of the neck. The swelling had been present for three months and had a variegated consistency. It moved with deglutition as well as with protrusion of the tongue. Intra-operatively, the lesion was cystic and was adherent to the hyoid bone. Sistrunk operation was done. The post-operative histopathology showed papillary carcinoma in the thyroglossal duct cyst. The standard treatment is Sistrunk procedure with close follow-up of the patient. Patients with metastatic disease require a total thyroidectomy and in the presence of neck secondaries, neck dissection has to be done.The diagnosis can be missed because of the rarity of this condition. Carcinoma should be suspected in a thyroglossal duct cyst when presenting for the first time in the elderly age group.

Cryptococcosis is a disseminated fungal infection commonly affecting the lungs and the central nervous system in immunocompromised patients. Herein we report a rare case of isolated mastoid osteomyelitis due to Cryptococcus neoformans which was initially not recognized due to its uncommon presentation akin to a Betzold’s abscess. A 61-year-old male presented with complaints of left ear discharge for a 1-month duration associated with a swelling in the left side of the neck for which he underwent incision and drainage without any significant improvement. a contrast-enhanced computed tomography (CT) scan revealed extensive erosion of the left mastoid cavity with a collection. Intraoperatively, red friable granulation tissue was seen within the antrum, histopathology of which revealed capsulated yeast forms. The patient underwent left canal wall down mastoidectomy along with antifungal treatment. Bone involvement is rare in patients with cryptococcal infection with vertebrae being the most common site of cryptococcal osteomyelitis. The clinical presentation is nonspecific and can pose a diagnostic dilemma, as the condition can mimic both Betzold’s abscess as well as malignancy. CT findings and the use of specific fungal stains in histopathology will aid in diagnosing this condition. The purpose of this case report is to establish the first case of isolated cryptococcal mastoid osteomyelitis in the database of fungal osteomyelitis. The confirmation of fungal osteomyelitis should be based on histopathological examination. The possibility of fungal osteomyelitis should be borne in mind in any case of insidiously increasing mass with unclear etiology so that prompt antifungal therapy with surgical debridement is initiated.

Tumors arising in the spermatic cord are very rare. The common benign tumors of the spermatic cord include adenomatoid tumor, lipoma, neurofibroma, and leiomyoma. We report a rare case of fibrous pseudotumor of the spermatic cord presenting clinically as a hydrocele. A 28-year-old male presented with the complaint of swelling in the left scrotum, which gradually progressed in size over four years. Clinically, the swelling was soft and fluctuant. The left testis was not separately made out and a diagnosis of left hydrocele was made. On scrotal exploration, a large 12 x 7 cm fleshy mass was seen in the left hemiscrotum with the left testis adherent to the upper pole of the mass. The mass was dissected out from the testis, and the histology showed features of fibrous pseudotumor of the spermatic cord. Fibrous pseudotumor of the spermatic cord is a very rare entity and can pose a diagnostic challenge. Preoperative scrotal ultrasound and intraoperative frozen section assessment can prevent unnecessary orchiectomies in young patients with paratesticular fibrous pseudotumors.