Chromium tolerance, bioaccumulation and localization in plants: An overview

In the current industrial scenario, chromium (Cr) as a metal is of great importance, but poses a major threat to the environment. Phytoremediation provides an environmentally sustainable, ecofriendly, cost effective approach for environmental cleanup of Cr. This review presents the current status of phytoremediation research with particular emphasis on cleanup of Cr contaminated soil and water systems. It gives a detailed account of the work done by different authors on the Cr bioavailability, uptake pathway, toxicity and storage in plants following the phytoextraction mechanism. This paper also describes recent findings related to Cr localization in hyperaccumulator plants. It gives an insight into the processes and mechanisms that allow plants to remove Cr from contaminated sites under varying conditions. These detailed knowledge of changes in plant metabolic pool in response to Cr stress would immensely help understand and improve the phytoextraction process. Further, this review provides a detailed understanding of Cr uptake and detoxification mechanism by plants that can be applied in developing a suitable approach for a better applicability of the process.

Review of intraoperative parathormone monitoring with the miami criterion: A 25-year experience

With the development of imaging and localization studies, focused parathyroidectomy with use of intraoperative parathormone monitoring (IPM) is the mainstay of treatment for primary hyperparathyroidism at many health care centers both nationally and internationally. Focused parathyroidectomy guided by IPM allows for surgical excision of the offending parathyroid gland through smaller incisions. The Miami criterion is a protocol that uses a “> 50% parathormone (PTH) drop” from either the greatest pre-incision or pre-excision measurement of PTH in a blood sample taken 10 min following resection of hyperfunctioning glands. Following removal of the hyperfunctioning parathyroid gland, a > 50% PTH drop at 10 min indicates completion of parathyroidectomy, and predicts operative success at 6 mo. IPM using the Miami criterion has demonstrated equal curative rates of > 97%, which is comparable to the traditional bilateral neck exploration. The focused approach, however, is associated with shorter recovery times, improved cosmesis, and lower risk of postoperative hypocalcemia.

Long-term effectiveness of localization studies and intraoperative parathormone monitoring in patients undergoing reoperative parathyroidectomy for persistent or recurrent hyperparathyroidism

BACKGROUND

Reoperative parathyroidectomy (RPTX) for persistent or recurrent hyperparathyroidism is associated with a high rate of operative failure. The long-term effectiveness of RPTX using localization studies and intraoperative parathormone monitoring (IPM) was examined.

METHODS

Retrospective analysis of prospectively collected data from patients undergoing targeted RPTX with IPM for persistent or recurrent hyperparathyroidism was performed. Persistent hyperparathyroidism was defined as elevated calcium and parathormone (PTH) levels above normal range less than 6 months after parathyroidectomy. Recurrent hyperparathyroidism was defined as elevated calcium and PTH levels greater than 6 months after successful parathyroidectomy. Sensitivity and positive predictive value (PPV) for sestamibi, surgeon-performed ultrasound, intraoperative PTH dynamics, and surgical outcomes were evaluated.

RESULTS

Of the 1,064 patients, 69 patients underwent 72 RPTXs with localizing studies and IPM. Sestamibi (n = 69) had a sensitivity of 74% and a PPV of 83%, whereas surgeon-performed ultrasound (n = 38) had a sensitivity of 55% and a PPV of 76%. IPM had a sensitivity of 100% and a PPV of 98%. An intraoperative PTH drop greater than or equal to 50% was predictive of operative success (P < .01). Overall, operative success and recurrence were 94% and 1.4%, with a mean patient follow-up of 59 ± 12.8 months.

CONCLUSION

RPTX can be performed in a targeted approach using preoperative localization studies and IPM, leading to a low rate of complications and a high rate of long-term operative success.