Arrhythmias and the athlete: mechanisms and clinical significance: reply

We would like to thank Dr Whyte and his coworkers for theirinterest in our study¹ and their critical reflection on thecause and effect relationship between right ventricular (RV)dysfunction and ventricular arrhythmias (VA). Tachycardia-induced cardiomyopathy is indeed a well-known entity,mainly as the     

EDITORIAL: Another Decade: Challenges and Promises

Internationally, the alcohol and other drug (AOD) field has an increasing focus on recovery-oriented care, however there has been little research addressing the impacts in Australia. This study explores the attitudes of AOD clinicians toward recovery-oriented care in Victoria. Data was collected from 50 AOD clinicians and managers across six AOD services. Data collection included completion of a structured questionnaire addressing recovery attitudes and beliefs and semistructured group interviews. Although participants agreed with the broad concept of recovery, there was disagreement over the appropriateness of recovery as a term. The findings support that the development of a set of guiding recovery principles would be more useful than a simple definition.     

Minireview: GNAS: normal and abnormal functions

GNAS is a complex imprinted gene that uses multiple promoters to generate several gene products, including the G protein alpha-subunit (G(s)alpha) that couples seven-transmembrane receptors to the cAMP-generating enzyme adenylyl cyclase. Somatic activating G(s)alpha mutations, which alter key residues required for the GTPase turn-off reaction, are present in various endocrine tumors and fibrous dysplasia of bone, and in a more widespread distribution in patients with McCune- Albright syndrome. Heterozygous inactivating G(s)alpha mutations lead to Albright hereditary osteodystrophy. G(s)alpha is imprinted in a tissue-specific manner, being primarily expressed from the maternal allele in renal proximal tubules, thyroid, pituitary, and ovary. Maternally inherited mutations lead to Albright hereditary osteodystrophy (AHO) plus PTH, TSH, and gonadotropin resistance (pseudohypoparathyroidism type 1A), whereas paternally inherited mutations lead to AHO alone. Pseudohypoparathyroidism type 1B, in which patients develop PTH resistance without AHO, is almost always associated with a GNAS imprinting defect in which both alleles have a paternal-specific imprinting pattern on both parental alleles. Familial forms of the disease are associated with a mutation within a closely linked gene that deletes a region that is presumably required for establishing the maternal imprint, and therefore maternal inheritance of the mutation results in the GNAS imprinting defect. Imprinting of one differentially methylated region within GNAS is virtually always lost in pseudohypoparathyroidism type 1B, and this region is probably responsible for tissue-specific G(s)alpha imprinting. Mouse knockout models show that G(s)alpha and the alternative G(s)alpha isoform XLalphas that is expressed from the paternal GNAS allele may have opposite effects on energy metabolism in mice.     

Minireview: RET: normal and abnormal functions

The RET gene encodes a single-pass transmembrane receptor tyrosine kinase. RET is the oncogene that causes papillary thyroid carcinoma and medullary thyroid carcinoma. The latter may arise as a component of multiple endocrine neoplasia type 2 syndromes; germline mutations in RET are responsible for multiple endocrine neoplasia type 2 inheritance. In this report we review data on the mechanisms leading to RET oncogenic conversion and on RET targeting as a strategy in thyroid cancer treatment.     

Minireview: aldosterone and the cardiovascular system: genomic and nongenomic effects

There is clear evidence for rapid nongenomic effects of aldosterone in the cardiovascular system in addition to its well characterized effects of unidirectional transepithelial sodium transport. Many of these effects are mediated by the classical mineralocorticoid receptors, although others may be exerted independently. Given that mineralocorticoid receptors are largely constitutively occupied but not activated by physiological glucocorticoids, effects of aldosterone administered in vitro or in vivo may or may not equate with true physiological mineralocorticoid roles. In many systems (e.g. blood pressure regulation and cardiac fibrosis), the time course of effects is such that it is not possible, and perhaps not important, to distinguish between rapid nongenomic and classical genomic effects in the context of homeostatic physiology.     

Ethanol and Polyamine Metabolism: Physiologic and Pathologic Implications: A Review

This review summarizes the effects of ethanol on the metabolism of polyamines (putrescine, spermidine, and spermine), which are endogenous polycations required for cell physiology, growth, and differentiation. Polyamines regulate DNA, RNA, and protein syntheses; stabilize ribosomes, membranes, and nucleic acids; and protect the cell against lipid peroxidation. Polyamine biosynthesis and catabolism may change after acute and chronic ethanol treatment, thereby playing a negative or positive role in the ethanol-induced injury on liver, extrahepatic tissues, embryo, and fetus.     

Laparoscopic Cholecystectomy: Bile Duct and Vascular Injuries: Management and Outcome

Background: This is a retrospective study of 32 consecutive patients referred in the period 1992-2000 for management of serious bile duct injuries caused by elective laparoscopic cholecystectomy. Methods: The patients were referred on median 29 days (0 days to 34 months). Only 7 patients were referred immediately after discovery of the injury. At the local hospital, 25 patients underwent various procedures in attempts at repair. Ten of the patients were treated for bile duct strictures after previous repairs in other hospitals. Results: At referral, 23 patients (72%) had complete transection of the bile duct, while 9 had bile leakage injuries. Additional complications were occlusion of the right hepatic artery in 8 patients (24%) and occlusion of the mesenteric superior artery in 1 patient. Infectious complications were prominent in 21 patients (70%), 6 of whom had septicaemia. Operative management with hepaticojejunostomy Roux-Y was employed in 22 patients. Various non-operative strategies were chosen, including endoscopically or transhepatic stenting of the bile duct and embolization of the right hepatic artery. There was no difference in hospital stay between operative and non-operative procedures which on median was 16 days ( range 7-69 days). Three patients died: one had thrombosis of the superior mesenteric artery, while the other two died of complications to bile peritonitis. Median observation period is 5 years (5 months to 8 years). Two patients have cholangitis; both had injury to the right hepatic artery. The other patients all had normal ultrasonograms of the liver and normal/almost normal liver function tests. Conclusions: Bile duct injuries continue to occur, are serious and may result in death. Injury to the right hepatic artery is present in many cases. Patients are referred late to a competent center, resulting in serious infection in 70%.     

Laparoscopic cholecystectomy: bile duct and vascular injuries: management and outcome

BACKGROUND: This is a retrospective study of 32 consecutive patients referred in the period 1992-2000 for management of serious bile duct injuries caused by elective laparoscopic cholecystectomy. METHODS: The patients were referred on median 29 days (0 days to 34 months). Only 7 patients were referred immediately after discovery of the injury. At the local hospital, 25 patients underwent various procedures in attempts at repair. Ten of the patients were treated for bile duct strictures after previous repairs in other hospitals. RESULTS: At referral, 23 patients (72%) had complete transection of the bile duct, while 9 had bile leakage injuries. Additional complications were occlusion of the right hepatic artery in 8 patients (24%) and occlusion of the mesenteric superior artery in 1 patient. Infectious complications were prominent in 21 patients (70%), 6 of whom had septicaemia. Operative management with hepaticojejunostomy Roux-Y was employed in 22 patients. Various non-operative strategies were chosen, including endoscopically or transhepatic stenting of the bile duct and embolization of the right hepatic artery. There was no difference in hospital stay between operative and non-operative procedures which on median was 16 days ( range 7-69 days). Three patients died: one had thrombosis of the superior mesenteric artery, while the other two died of complications to bile peritonitis. Median observation period is 5 years (5 months to 8 years). Two patients have cholangitis; both had injury to the right hepatic artery. The other patients all had normal ultrasonograms of the liver and normal/almost normal liver function tests. CONCLUSIONS: Bile duct injuries continue to occur, are serious and may result in death. Injury to the right hepatic artery is present in many cases. Patients are referred late to a competent center, resulting in serious infection in 70%.     

Gerontology and Education:

Since the early 1970s, educational gerontology has been active in both researching and advocating continuing education for older persons. However, very little has been states in this growing body of literature about how education in the later years relates to the process of aging itself, that area of inquiry which has traditionally been researched and reported by the much older body of literature known as social gerontology. In this essay, two longstanding social gerontological theories are analyzed for the ways they explain interest and participation in adult education on the part of older persons. While neither the activity nor the disengagement theory is explicit in articulating a relationship between the aging process and the need to learn, both do so implicitly. Implications from these social theories for educational program development are made as are recommendations for examining the present practice of educators and health professionals.     

Sexuality and Aging:

Previous research has been conducted regarding preferences of physicians for life-sustaining treatments for themselves, but there is a dearth of data on personal use of advance directives (ADs) by geriatricians specifically. Using a phone survey, we contacted all graduates of the geriatric fellowship program to assess their personal use of advance directives and their personal preferences for life-sustaining treatment. Of the 124 living graduates of the Parker Jewish Institute for Health Care and Rehabilitation, 70 agreed to participate. One third of respondents had established ADs for themselves, with higher rates in women than men (p = .054). Older geriatricians were significantly more likely to have advance directives (exact trend test yields, p < .0001). In general, respondents did not inform their health care providers about their desires for end-of-life care. This study revealed that the majority of fellowship-trained geriatricians did not formally establish advance directives for themselves. Further research is needed to determine whether physicians who establish advance directives for themselves are more likely to encourage their patients to do so.