Adult living donor liver transplantation: Preferences about donation outside the medical community

An increasing number of transplant centers are performing adult living donor liver transplantation (LDLT). We evaluated peoples' perspectives on possible outcomes of living donation, thresholds for donating, and views regarding the donation process. One hundred fifty people were surveyed; half were from a medical care group serving an indigent population and half were from a private clinic. Preferences about outcomes of adult living donation were ranked and quantified on a visual analogue scale. Thresholds for donation to a loved one were quantified. Sixty percent of the respondents suggested they would prefer to donate and die and have the transplant recipient live rather than forego donation and have the potential transplant recipient die of liver failure. Participants' stated threshold for living donation was a median survival for themselves of only 79%. They would require that their loved one have a median survival of 55% with transplantation before they would agree to donate. Respondents from the medical care group reported higher survival thresholds for themselves and the transplant recipient, and race was the most statistically significant predictor of those thresholds. Sex was more predictive of threshold probabilities from the private clinic. Eighty-one percent of the respondents believed that the potential donor, not a physician, should have the final say regarding candidacy for living donation. In conclusion, the findings of this survey support the use of adult LDLT. Most respondents were willing to accept mortality rates that far exceed the estimated risk of donation and favored outcomes in which a loved one was saved.

Inducible expression of herpes simplex virus thymidine kinase increases sensitivity to ganciclovir but does not enhance bystander effect in breast cancer cells

Delivery of cancer chemotherapy directly to the cancer cell has great appeal. Previous studies using adenoviral transfer of the herpes simplex virus thymidine kinase (HSV-tk) gene followed by ganciclovir (GCV) in an ascites model of breast cancer was successful in reducing tumor burden and prolonging life. However, increasing the viral dose resulted in increased toxicity and host mortality emphasizing the need for an improved therapeutic ratio. To test the hypothesis that enhancement of HSV-tk gene expression would lead to increased sensitivity to GCV and improved bystander effect, we created breast cancer cells expressing HSV-tk under the control of the inducible tetracycline promoter. Using this system, we could inducibly increase gene expression and biochemical activation of HSV-tk. These increased levels of HSV-tk decreased the IC50 to GCV nearly 50-fold. However, the bystander effect was not enhanced by increasing HSV-tk gene expression. We conclude that increased HSV-tk gene expression improves sensitivity to CCV. However, additional measures, such as increased gap junction communication, will likely be needed to enhance the bystander effect and the therapeutic efficacy of this strategy.

Paraduodenal hernia presenting as unexplained recurrent abdominal pain

We present a case of a 29-yr-old female nurse who presented with an 8-h history of abdominal pain. She had had similar episodes (twice/yr) over the last 5 yr, and the pain had usually resolved spontaneously. Prior investigations including laboratory studies, plain films of the abdomen, an abdominal and pelvic ultrasound, and a CT scan yielded no diagnosis. Her pain was previously considered to be either psychosomatic or a variant of irritable bowel syndrome. On this admission, an evaluation and subsequent enteroclysis revealed a left paraduodenal hernia. The importance of considering paraduodenal hernias in the differential diagnosis of unexplained intermittent abdominal pain is discussed here.

Solid and papillary epithelial neoplasm of the pancreas. Report of a case with diagnosis by fine needle aspiration cytology

BACKGROUND

Solid and papillary epithelial neoplasm of the pancreas is a distinct clinicopathologic entity. It has a benign clinical course, and surgical resection can be curative.

CASE

A 17-year-old female presented with a mass measuring about 12 cm in the epigastrium and left hypochondrium. Fine needle aspiration cytology (FNAC) showed papillae with a central fibrovascular core and lined with many layers of bland-appearing cells exhibiting nuclear grooving. These features, along with ultrasound and computed tomographic findings, led to an accurate preoperative diagnosis.

CONCLUSION

In the setting of typical clinical and radiologic findings, it is possible to make a correct preoperative diagnosis by FNAC. Doing so has important implications for management.

Evaluation of an expert system on lymph node pathology

BACKGROUND

Pathfinder is an Expert System that assists pathologists in making accurate diagnoses in the domain of lymph-node pathology. Pathfinder provides a differential diagnosis based on the initial histological feature(s) observed by the pathologist, and suggests to the user additional histological features for observation that are likely to narrow the differential diagnosis.

PURPOSE

To evaluate the diagnostic accuracy of pathologists with and without the Pathfinder.

METHODS

Thirty H&E stained slides from 30 lymph node biopsy specimens on which a Consensus diagnosis was made by two experts were reviewed by 19 pathologists to evaluate Pathfinder. After a period of training, 10 pathologists using Pathfinder (Interactive Computer Method) and 9 pathologists using the Routine Method (diagnosis without computer) determined a differential diagnosis for 15 slides (Test 1). Pathologists were then crossed over, trained, and evaluated the remaining 15 slides (Test 2). For each test, the proportion of "correct" diagnoses was compared between methods. In addition, the information integration attributes (making logical diagnosis given a set of specific histologic features) of Pathfinder and pathologists were compared. Finally, feature identification and quantification skills of pathologists were determined and correlated with the percent correct diagnosis.

RESULTS

The diagnostic accuracy using Pathfinder was greater than that using the Routine Method (40% v 32%, P = .02). Diagnostic accuracy for the group of pathologists who made diagnosis using the Routine Method in Test 1 increased when they made diagnosis using Pathfinder in Test 2 (27% to 44%, P < .0001). The proportion of correct diagnosis for the group of pathologists who used Pathfinder in Test 1 remained virtually unchanged when they gave up Pathfinder in Test 2 (35% to 37%). The percentage of incompatible feature identification ("atypical proliferation" diagnosis) was significantly lower after using Pathfinder (P < .0001). In addition, information integration attributes of Pathfinder were significantly superior than that of the pathologists (P < .0001).

CONCLUSIONS

Pathfinder is a valuable tool that assists pathologists in making accurate diagnosis because it has superior attributes than pathologists to integrate information and to screen for observations incompatible with any specific disease.

Endoscopic removal of a toothpick from the transverse colon

We describe the case of a patient who presented with abdominal pain, weight loss, and night sweats of 8 wk duration due to the impalement of a toothpick in the transverse colon. The toothpick, which was inadvertently swallowed, was successfully removed during colonoscopy. Therapeutic colonoscopy has replaced or lessened to a significant degree the need for traditional open surgical procedures to extract foreign bodies from the colon. Unexplained abdominal pain and constitutional symptoms should alert the clinician to the possibility of a foreign body.

An Information Mediator Network for Tasks in Dynamic Environments

Coordination of activities among information workers and services, tracking and managing activities, and intelligent distribution of information are essential to the efficient operation of any large enterprise. This is particularly important in the healthcare domain, where many different organizations must cooperate to provide patient care reliably in a dynamically changing environment. In this review paper we present a distributed system that supports cooperative problem solving, activity management, and intelligent delivery of information in dynamic and unreliable environments. The system consists of a network of task/context managers (TCMs). Each TCM manages a group of related agents. It maintains up-to-date information on availability, operational status, and activities of participating agents, and it acts as a mediator between service requesters and service providers. In addition, the TCM acts as a representative for its agents with other TCMs, allowing different groups of agents to collaborate with one another. This paper describes the system architecture, its implementation and capabilities including matchmaking, plan monitoring, and failure recovery. Our system has been used in prehospital emergency patient information management applications.

An Information Mediator Network for Tasks in Dynamic Environments

Coordination of activities among information workers and services, tracking and managing activities, and intelligent distribution of information are essential to the efficient operation of any large enterprise. This is particularly important in the healthcare domain, where many different organizations must cooperate to provide patient care reliably in a dynamically changing environment. In this review paper we present a distributed system that supports cooperative problem solving, activity management, and intelligent delivery of information in dynamic and unreliable environments. The system consists of a network of task/context managers (TCMs). Each TCM manages a group of related agents. It maintains up-to-date information on availability, operational status, and activities of participating agents, and it acts as a mediator between service requesters and service providers. In addition, the TCM acts as a representative for its agents with other TCMs, allowing different groups of agents to collaborate with one another. This paper describes the system architecture, its implementation and capabilities including matchmaking, plan monitoring, and failure recovery. Our system has been used in prehospital emergency patient information management applications.

A rationale for gene targeting in glaucoma therapy

One of the mainstays of glaucoma treatment is the use of drugs that decrease the secretion of aqueous humor fluid from the ciliary epithelium. Unfortunately, many currently available drugs that decrease aqueous humor production such as beta-adrenergic antagonists, may cause serious systemic side effects such as cardiac arrhythmias and arrest, pulmonary dysfunction, and CNS side effects such as decreased libido and depression. Efforts to develop effective aqueous suppressants that offer decreased morbidity and mortality in comparison to those currently available will likely rely on the ability to alter the function of specific cellular events which underlie aqueous humor production by the ciliary epithelium. However, the secretory process which results in aqueous humor production is incompletely understood and the identification of precise cellular mechanisms which underlie this process remain to be established. We will present a rationale for genetic approaches to regulate gene expression so that aqueous humor production may be specifically targeted in glaucoma patients. Techniques of gene transfer including homologous exchange recombination, and expression of antisense genes, will be discussed.

Hemodynamic and oxygen transport patterns for outcome prediction, therapeutic goals, and clinical algorithms to improve outcome. Feasibility of artificial intelligence to customize algorithms

A generalized decision tree or clinical algorithm for treatment of high-risk elective surgical patients was developed from a physiologic model based on empirical data. First, a large data bank was used to do the following: (1) describe temporal hemodynamic and oxygen transport patterns that interrelate cardiac, pulmonary, and tissue perfusion functions in survivors and nonsurvivors; (2) define optimal therapeutic goals based on the supranormal oxygen transport values of high-risk postoperative survivors; (3) compare the relative effectiveness of alternative therapies in a wide variety of clinical and physiologic conditions; and (4) to develop criteria for titration of therapy to the endpoints of the supranormal optimal goals using cardiac index (CI), oxygen delivery (DO2), and oxygen consumption (VO2) as proxy outcome measures. Second, a general purpose algorithm was generated from these data and tested in preoperatively randomized clinical trials of high-risk surgical patients. Improved outcome was demonstrated with this generalized algorithm. The concept that the supranormal values represent compensations that have survival value has been corroborated by several other groups. We now propose a unique approach to refine the generalized algorithm to develop customized algorithms and individualized decision analysis for each patient's unique problems. The present article describes a preliminary evaluation of the feasibility of artificial intelligence techniques to accomplish individualized algorithms that may further improve patient care and outcome.

Metabolic studies with 'Nutrauxil', an enteral feed preparation

A metabolic study was carried out in 6 patients requiring enteral feeding to investigate the effectiveness and tolerance of 'Nutrauxil', a ready-made liquid nutritional preparation, over a period of 8 days. The results of anthropometric and laboratory measurements, made initially and at the end of two 4-day periods, showed that the basic provision of 2000 kcal and 60 g protein per day with 'Nutrauxil' maintained patients in metabolic, electrolyte and nitrogen balance. No adverse effects were noted and the preparation was easy to administer. It was concluded that 'Nutrauxil' compared favourably with other enteral feed preparations with respect to its nutritional effectiveness on clinical, biochemical and economic grounds.