Porous dipeptide crystals as volatile-drug vessels.

Porous crystalline dipeptides absorb, reversibly from the gas phase, a series of volatile fluorinated ethers in use as anesthetics. Their vapor pressure was considerably reduced, with favorable guest capture and release. Variable channel sizes were customized for selective sorption and pressure thresholds were observed in the narrowest pores. 1H, 13C and 19F MAS NMR coupled with ab initio conformational analysis and grand canonical Monte Carlo simulations highlight the guest loading and arrangement adopted in the congruent nanochannels, suggesting how the anesthetics can accommodate in biochemical receptors.

Failure of radiotherapy in acromegaly.

BACKGROUND: Recent data has raised skepticism regarding the long-term effectiveness of radiotherapy (RxT) in acromegaly and its role as an ancillary tool to neurosurgery (Tx). PATIENTS: We evaluated 72 acromegalic patients previously submitted to RxT. Data were discarded in 23 patients, who were lost to follow-up, operated on after RxT or irradiated with techniques different from external conventional fractionated RxT. Among the remaining 49 (five with mixed GH-prolactin adenoma), 34 were irradiated after surgical failure and 15 as primary treatment. A second cycle of RxT was administered in two. RESULTS: (i) GH/IGF-I. After a median follow-up of 14 years (range 3-41), normal age-matched IGF-I levels were reached in eight patients (16%) after 10 years, and GH levels <2.5 microg/l in six (12%) after 9 years. The rate of persistently pathological hormonal levels was still 90% at 25 years. All patients with GH/IGF-I normalization had undergone irradiation without any antisecretory drug. Neither basal GH nor tumor size affected the outcome of RxT. In three patients (6%) a relapse/worsening occurred. (ii) Tumor size. Tumor shrank after 8.5 years in 24 patients (49%), in nine of whom during GH-suppressive treatment. Tumor shrinkage was not predictive of hormonal normalization. (iii) Side-effects. Hypopituitarism was diagnosed in four patients (selective in three and global in one) and GH deficiency in one. Three patients had neurological side-effects and meningioma was shown in two patients. CONCLUSION: RxT is unable to cure acromegaly, because it seldom achieves hormonal normalization even after a very prolonged follow-up. Concomitant antisecretory treatment seems to counteract its effects. RxT can still play a role in those patients with large tumor remnants, because of its capacity to shrink tumor size.

Synovial sarcoma of the esophagus simulating achalasia.

Synovial sarcoma is a rare malignancy occurring mainly in the extremities. Only seven cases have been described arising in the esophagus. All of them presented as a polypoid mass involving the upper third of the esophagus. A case of infiltrating synovial esophageal sarcoma simulating achalasia in a 63-year-old woman is reported. According to the literature, the location and the clinical pattern of this tumor are exceptional. The clinical features, pathologic findings, differential diagnosis, and management of this condition are discussed.