Diethylalkylsulfonamido(4-methoxyphenyl)methyl)phosphonate/phosphonic acid derivatives act as acid phosphatase inhibitors: synthesis accompanied by experimental and molecular modeling assessments

Purple acid phosphatases (PAPs) are binuclear metallo-hydrolases that have been isolated from various mammals, plants, fungi and bacteria. In mammals, PAP activity is associated with bone resorption and can lead to bone metabolic disorders such as osteoporosis; thus human PAP is an attractive target to develop anti-osteoporotic drugs. The aim of the present study was to investigate inhibitory effect of synthesized diethylalkylsulfonamido(4-methoxyphenyl)methyl)phosphonate/phosphonic acid derivatives as potential red kidney bean PAP (rkbPAP) inhibitors accompanied by experimental and molecular modeling assessments. Enzyme kinetic data showed that they are good rkbPAP inhibitors whose potencies improve with increasing alkyl chain length. Hexadecyl derivatives, as most potent compounds (K_i = 1.1 µM), inhibit rkbPAP in the mixed manner, while dodecyl derivatives act as efficient noncompetitive inhibitor. Also, analysis by molecular modeling of the structure of the rkbPAP-inhibitor complexes reveals factors, which may be important for the determination of inhibition specificity.

Two-step three-component process for one-pot synthesis of 8-alkylmercaptocaffeine derivatives

A two-step three-component process for one-pot synthesis of some 8-alkylmercaptocaffeine derivatives has been described using alkyl bromides, thiourea, and 8-bromocaffeine.

Pre-operative ultrasound for breast tumour measurements: is there potential for mismanagement?

The pre-operative size of breast tumour is the most important factor in determining feasibility of breast conserving surgery in operable breast cancer. Currently there is no consensus on the most accurate modality to measure tumour size. A prospective study of consecutive and unselected symptomatic patients with invasive breast cancer who had primary surgery between January 2006 and December 2007 was conducted. Patients with multi-focal and multi-centric tumours were excluded. The aim of this study was to find the correlation between histological size of invasive breast cancer and pre-operative tumour size as measured by ultrasound. Over this two year period, data for 192 patients was analysed for this study. The mean tumour diameter on ultrasound and histology was 19.5mm and 29 mm respectively. The difference between the means in the two modalities was found to be statistically significant (P<0.001).Ultrasound underestimates the true size of breast tumours as determined histologically. Inaccurate tumour size measurements may result in re-operations to achieve adequate margins.

Preventive effect of ginger (Zingiber officinale) pretreatment on renal ischemia-reperfusion in rats

BACKGROUND/AIMS

The present study examined the preventive effect of ginger against renal ischemia-reperfusion (I-R) injury.

METHODS

30 adult male rats were used. The animals were allocated to five groups of 6 rats: (1) normal (N), (2) normal + ginger (N+G), (3) right nephrectomy (Sham), (4) I-R, and (5) I-R + ginger (I-R+G). To induce renal ischemia, animals were unilaterally nephrectomized and subjected to 45 min of left renal pedicle occlusion with 24 h reperfusion. Ginger was administered orally 24 h and just before ischemia. At the end of the experiment, blood samples and urine were collected. The following renal functional parameters were studied: serum and urinary levels of creatinine and urea, fractional excretion of sodium, and creatinine clearance. Histopathological examination of the kidney was also performed.

RESULTS

Rats with renal I-R showed a significant increase in creatinine and urea concentration in serum and also a significant decrease in creatinine clearance compared with the other groups. In addition, renal histopathology in the I-R group showed severe alterations such as tubular dilatation and tubular epithelial necrosis. However, these changes were significantly reduced in the I-R+G group.

CONCLUSION

This study suggests that ginger is a useful agent for the prevention of renal ischemia reperfusion-induced injury.

The effect of 30 months of low-dose replacement therapy with recombinant human growth hormone (rhGH) on insulin and C-peptide kinetics, insulin secretion, insulin sensitivity, glucose effectiveness, and body composition in GH-deficient adults

The aim of the present study was to evaluate the long-term (30 months) metabolic effects of recombinant human GH (rhGH) given in a mean dose of 6.7 microg/kg x day (= 1.6 IU/day), in 11 patients with adult GH deficiency. Glucose metabolism was evaluated by an oral glucose tolerance test and an iv (frequently sampled iv glucose tolerance test) glucose tolerance test, and body composition was estimated by dual-energy x-ray absorptiometry. Treatment with rhGH induced persistent favorable changes in body composition, with a 10% increase in lean body mass (P < 0.001) and a 12% reduction of fat mass (P < 0.002); however, the glucose tolerance deteriorated significantly, and three patients developed impaired glucose tolerance. Fasting insulin level (P < 0.003) and the homeostasis model assessment insulin resistance score increased significantly, indicating a deterioration in insulin sensitivity; whereas the insulin sensitivity index, calculated from the frequently sampled iv glucose tolerance test, only decreased slightly. The clearance of C-peptide and insulin increased 100% and 60%, respectively, and the prehepatic insulin secretion was tripled during rhGH treatment; but related to the impairment in glucose tolerance, beta-cell response was still inappropriate. Our conclusion is that long-term rhGH-replacement therapy in GH deficiency adults induced a significant deterioration in glucose tolerance, profound changes in kinetics of C-peptide, and insulin and prehepatic insulin secretion, despite an increase in lean body mass and a reduction of fat mass. Therefore, rhGH treatment may precipitate diabetes in some patients already susceptible to the disorder.