Caution needed in using oral polio vaccine beyond the cold chain: Vaccine vial monitors may be unreliable at high temperatures.

Background & objectives: Stabilized live attenuated oral polio vaccine (OPV) is used to immunize children up to the age of five years to prevent poliomyelitis. It is strongly advised that the cold-chain should be maintained until the vaccine is administered. It is assumed, that vaccine vial monitors (VVMs) are reliable at all temperatures. VVMs are tested at 37°C and it is assumed that the labels reach discard point before vaccine potency drops to >0.6 log10. This study was undertaken to see if VVMs were reliable when exposed to high temperatures as can occur in field conditions in India. Methods: Vaccine vials with VVMs were incubated (10 vials for each temperature) in an incubator at different temperatures at 37, 41, 45 and 49.5°C. Time-lapse photographs of the VVMs on vials were taken hourly to look for their discard-point. Results: At 37 and 41°C the VVMs worked well. At 45°C, vaccine potency is known to drop to the discard level within 14 h whereas the VVM discard point was reached at 16 h. At 49.5°C the VVMs reached discard point at 9 h when these should have reached it at 3 h. Conclusion: Absolute reliance cannot be placed on VVM in situation where environmental temperatures are high. Caution is needed when using ‘outside the cold chain’ (OCC) protocols.

Sodium iodide symporter, estrogen receptor, and progesterone receptor expression in carcinoma breast - An immunohistochemical analysis.

Background: Sodium iodide symporter (NIS), a transporter of iodine is essential for thyroid hormone biosynthesis. It also plays a role in the radioiodine treatment of thyroid cancers. NIS mediated radioiodine transport to breast cancers is under active investigation due to its potential therapeutic utility. Cellular localization and quantification using immunohistochemistry may provide clues for its utility in management of carcinoma breast. Materials and Methods: Human NIS (hNIS) expression was therefore assessed by utilizing a rabbit polyclonal antibody raised against a cloned hNIS in different grades of infiltrating duct carcinoma of breast and its metastatic deposits namely in lymph nodes, bone marrow, and endometrium. Further, hNIS expression was compared with prognostic markers namely estrogen receptor (ER) and progesterone receptor (PR). Results: hNIS was positive in 90.6% cases (29/32) and Scarff-Bloom-Richardson grading was done in 25 cases and 23 cases were NIS positive. Among nongraded cases, 2/2 cases of carcinoma in-situ were positive and 4/5 were positive in cases having post therapy residual tumor status. The strong positivity for hNIS was seen irrespective of ER or PR status and of grade of breast carcinoma and correlated well with western blot analysis. In all the three metastatic sites, NIS was positive in the tumor. Conclusion: These findings indicate the utility of immnohistochemistry for NIS as a new potential prognostic marker and may provide guidance for possible radio iodine therapy in breast cancer patients.

Human sodium iodide symporter (hNIS) in fibroadenoma breast—A immunohistochemical study.

Human sodium iodide symporter (hNIS), responsible for the active transport of iodine is an integral plasma membrane glycoprotein present in the thyroid cells and extrathyroid tissues like breast and salivary glands. If its functional form is unequivocally shown in benign or malignant breast tissues, then it may serve as a basis for diagnosis and treatment using radioactive iodine. With an aim to analyze the hNIS expression in a distinct benign breast condition of fibroadenoma, biopsy proven fibroadenoma tissues, normal non-lactating breast tissue and biopsy proven infiltrating duct carcinoma tissues were examined for hNIS expression using immunohistochemistry. Out of 20 biopsy proven fibroadenoma tissues, 19 (95%) showed positivity for hNIS protein and only one was negative. Of these 10% were mildly positive, 50% cases were moderately positive and 35% showed intense positivity. None of the control tissue obtained from reduction mammoplasty specimens or normal breast tissues samples (5 cms away from the tumor) were positive. hNIS was also intensely positive  in 9 out of 10 (90%) infiltrating duct carcinoma tissues and moderately positive in one case. These preliminary results show that hNIS was present in high frequency as demonstrated by immunohistochemistry in fibroadenoma breast.