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David B Adams

Publications and source records attributed to David B Adams.

15 recordsLinked to original sources
PubMed2007

Cardiac resynchronization therapy and the emerging role of echocardiography (part 1): indications and results from current studies.

Cardiac resynchronization therapy (CRT) has been established as an adjunctive treatment for patients with left ventricular systolic dysfunction and medically refractory heart failure with a wide QRS interval. Echocardiography can be used to determine the response in left ventricular structure and function after device implantation and emerging evidence as a method for selection of patients who may derive clinical benefit from CRT. This review discusses the applications of CRT, including results of clinical trials and the current experience using echocardiography. Part 2 will address the practical aspects of obtaining echocardiographic data in patients who are potential candidates for CRT and optimization of pacemaker settings after device implantation.

Cardiac Pacing, Artificial↗
PubMed2007

Cardiac resynchronization therapy and the emerging role of echocardiography (part 2): the comprehensive examination.

Cardiac resynchronization therapy has been established as an adjunctive treatment for patients with severe left ventricular systolic dysfunction and medically refractory heart failure symptoms with a prolonged electrocardiographic QRS interval. Echocardiography has emerged as a useful method to evaluate patients who are considered for cardiac resynchronization therapy. This review outlines measurements of ventricular performance to be used in this patient population including echocardiographic optimization of cardiac resynchronization therapy device settings.

Cardiac Pacing, Artificial↗
PubMed2006

Reoperative surgery for chronic pancreatitis: is it safe?

INTRODUCTION: Eleven percent to fifty-six percent of patients do not achieve adequate pain relief with initial operative treatment for chronic pancreatitis, and reoperations for recurrent or persistent pain are common. This study evaluates the influence of prior pancreatic procedures on operative morbidity for chronic pancreatitis. METHODS: The records of 336 consecutive patients who underwent pancreaticoduodenectomy (PD, n=78), lateral pancreaticojejunostomy (LPJ, n=152), distal pancreatectomy (DP, n=83), transduodenal sphincteroplasty (SP, n=20), and total pancreatectomy (TP, n=3) for chronic pancreatitis were retrospectively reviewed and analyzed. RESULTS: Seventy-four patients underwent reoperation after failed prior pancreatic surgery. Patients with de novo pancreatic operations had a similar complication rate as those with reoperation (PD: 48% versus 65%, P>0.05; LPJ: 23% versus 23%, P>0.05; DP: 26% versus 28%, P>0.05; SP: 21% versus 100%, P>0.05). Major complications such as pancreatic leak or abdominal abscess were similar in the two groups. Minor complications such as delayed gastric emptying or wound infections were more common in the reoperation group. There was no difference in postoperative hospital length of stay. CONCLUSIONS: Patients who undergo reoperative surgery for chronic pancreatitis have an increased risk for minor perioperative complications. The overall complication rate and the incidence of major complications are similar compared to de novo procedure. Reoperative surgery therefore appears feasible and safe in experienced hands.

Adolescent↗
PubMed2006

Should elective surgery for chronic pancreatitis be performed in high-risk patients?

As morbidity and mortality rates for pancreatic surgery have improved over the past decades, patients with major medical comorbidities have been considered for operative treatment. The influence of poor health status on operative morbidity in patients with chronic pancreatitis is evaluated in this study. The records of 313 consecutive patients who underwent pancreaticoduodenectomy (n = 78), distal pancreatectomy (n = 83), or lateral pancreaticojejunostomy (n = 152) for chronic pancreatitis were retrospectively reviewed and analyzed. Patients' risk for adverse outcome resulting from overall health status was audited using age, comorbidities, and Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (POSSUM) physiological score. Univariate analysis showed that patient's age did not contribute to change in morbidity (odds ratio [OR] = 1.01, P = 0.59). The presence of cardiac disease but not other comorbidities increased adverse outcome affected the need for intensive care unit stay and length of hospital stay (morbidity: 29% vs. 51%, OR = 2.6, P = 0.003). POSSUM physiological score was associated with an increase in morbidity and mortality (morbidity: OR = 1.16, P = 0.001; mortality: OR = 1.49, P = 0.001), in particular intraabdominal abscesses. Multivariate analysis showed that the only variable independently correlating with perioperative complications was POSSUM physiological score. Single comorbidities do not independently influence outcome after operations for chronic pancreatitis. A combination of several comorbidities is associated with an increase in postoperative infectious morbidity and mortality. High-risk patients should not be excluded from operative treatment, but need to be closely selected on a case-by-case basis.

Abdominal Abscess↗
PubMed2005

Brain mechanisms of aggressive behavior: an updated review.

During the 25 years since a motivational systems model was proposed to explain the brain mechanisms of aggressive behavior (D.B. Adams. Brain mechanisms for offense, defense, and submission. Behav. Brain. Sci. 2, (1979a) 200-241) considerable research has been carried out. Updating the model in the light of this research requires several changes. A previous distinction between submission and defense systems is abandoned and, instead, it is proposed that two distinct subsets of the defense motivational mechanism may be recognized, one for anti-predator defense and the other for consociate defense. Similarly, the offense motivational mechanism is now considered to have at least two subsets, one mediating territorial and the other competitive fighting. Data continue to indicate that the defense motivational mechanism is located in the midbrain central gray and adjoining tissue. Also data tend to support the hypothesis that the offense motivational mechanism is located in the hypothalamus at the level of the anterior hypothalamus. Consideration is also given to a motivational system for patrol/marking which is related to aggressive behavior. Research is reviewed that bears on the neural structure of motivating and releasing/directing stimuli and motor patterning mechanisms of offense, defense and patrol/marking, as well as the location of learning and hormonal effects, and attention is given to how the model can be tested.

Aggression↗
PubMed2005

The effect of malnutrition on morbidity after Surgery for chronic pancreatitis.

Protein-energy malnutrition is a notable problem in the management of patients with chronic pancreatitis. The effect of malnutrition on pancreatic surgery is not well known. The records of 313 consecutive patients who underwent lateral pancreaticojejunostomy (LPJ, n = 152), pancreaticoduodenectomy (PD, n = 78), or distal pancreatectomy (DP, n = 83) for chronic pancreatitis were retrospectively reviewed and analyzed. Subjective Global Assessment, Nutritional Risk Index, and Instant Nutritional Assessment were used to assess the nutritional state. An average of all three nutritional indexes was established, and patients were categorized into well nourished (n = 101) as well as mild (n = 91), moderate (n = 94), and severe malnourished (n = 27). Poor nutritional state was associated with an increase in postoperative complication rate (LPJ: well nourished 14%, mild 25%, moderate 31%*, severe 50%*; PD: well nourished 44%, mild 44%, moderate 60%, severe 88%*; DP: well nourished 17%, mild 13%, moderate 30%, severe 55%*; *P < 0.045 vs well nourished). Low serum albumin levels also increased operative morbidity. The increase in morbidity was reflected by a higher rate of infectious complications as well as increased ICU stay. Body mass index and weight loss did not contribute to change in outcome. Malnutrition was associated with a higher incidence of postoperative complications after surgery for chronic pancreatitis. An increase in operative morbidity might be related to decreased protein synthesis and impaired immunocompetence.

Adult↗
PubMed2004

Localization of ABCG5 and ABCG8 proteins in human liver, gall bladder and intestine.

BACKGROUND: The molecular mechanisms that regulate the entry of dietary sterols into the body and their removal via hepatobiliary secretion are now beginning to be defined. These processes are specifically disrupted in the rare autosomal recessive disease, Sitosterolemia (MIM 210250). Mutations in either, but not both, of two genes ABCG5 or ABCG8, comprising the STSL locus, are now known to cause this disease and their protein products are proposed to function as heterodimers. Under normal circumstances cholesterol, but not non-cholesterol sterols, is preferentially absorbed from the diet. Additionally, any small amounts of non-cholesterol sterols that are absorbed are rapidly taken up by the liver and preferentially excreted into bile. Based upon the defects in sitosterolemia, ABCG5 and ABCG8 serve specifically to exclude non-cholesterol sterol entry at the intestinal level and are involved in sterol excretion at the hepatobiliary level. METHODS: Here we report the biochemical and immuno-localization of ABCG5 and ABCG8 in human liver, gallbladder and intestine using cell fractionation and immunohistochemical analyses. RESULTS: We raised peptide antibodies against ABCG5 and ABCG8 proteins. Using human liver samples, cell fractionation studies showed both proteins are found in membrane fractions, but they did not co-localize with caveolin-rafts, ER, Golgi or mitochondrial markers. Although their distribution in the sub-fractions was similar, they were not completely contiguous. Immunohistochemical analyses showed that while both proteins were readily detectable in the liver, ABCG5 was found predominately lining canalicular membranes, whereas ABCG8 was found in association with bile duct epithelia. At the cellular level, ABCG5 appeared to be apically expressed, whereas ABCG8 had a more diffuse expression pattern. Both ABCG5 and ABCG8 appeared to localize apically as shown by co-localization with MRP2. The distribution patterns of ABCG5 and ABCG8 in the gallbladder were very similar to each other. In the small intestine both ABCG5 and ABCG8 appear to line the brush border. However, at the level of the enterocyte, the cellular distribution patterns of ABCG5 and ABCG8 differed, such that ABCG5 was more diffuse, but ABCG8 was principally apical. Using standard deglycosylation methods, ABCG5 and ABCG8 do not appear to be glycosylated, suggesting a difference between human and mouse proteins. CONCLUSION: We report the distribution patterns of ABCG5 and ABCG8 in human tissues. Cell fractionation studies showed that both proteins co-fractionated in general, but could also be found independent of each other. As predicted, they are expressed apically in both intestine and liver, although their intracellular expression patterns are not completely congruent. These studies support the concept of heterodimerization of ABCG5 and ABCG8, but also support the notion that these proteins may have an independent function.

ATP Binding Cassette Transporter, Subfamily G, Mem↗
PubMed2004

Feasibility of point-of-care echocardiography by internal medicine house staff.

OBJECTIVE: To determine whether internal medicine house staff with limited training in echocardiography can use point-of-care echocardiography to make simple, clinically important diagnoses. BACKGROUND: Availability of small, portable ultrasound devices could make point-of-care echocardiography widely available. The training required to perform point-of-care echocardiography has not been established. METHODS: Medical house staff participated in a 3-hour point-of-care echocardiography training program. Patients scheduled for standard echocardiography as part of clinical care underwent point-of-care echocardiography within 24 hours to assess four common clinically important diagnoses. Each standard echocardiogram was interpreted twice. Agreement (kappa) was calculated between point-of-care and standard echocardiography by using standard echocardiography as the gold standard and between the two interpretations of standard echocardiography. RESULTS: Agreement (kappa) between point-of-care echocardiography and standard echocardiography was 75% (0.51) for left ventricular dysfunction (ejection fraction <55%), 79% (0.31) for moderate or severe mitral regurgitation, 92% (0.32) for aortic valve thickening or immobility, and 98% (0.51) for moderate or large pericardial effusion. Agreement between the two interpretations of standard echocardiography was 83% (0.63) for left ventricular dysfunction, 92% (0.68) for moderate or severe mitral regurgitation, 95% (0.62) for aortic valve thickening or immobility, and 97% (0.53) for moderate or large pericardial effusion. CONCLUSIONS: Medical house staff with limited training in echocardiography can use point-of-care echocardiography to assess left ventricular function and pericardial effusion with moderate accuracy that is lower than that of standard echocardiography. Assessment of valvular disease and other diagnoses likely requires more training and/or experience in echocardiography.

Echocardiography↗
PubMed2003

Carl Gussenbauer: pioneer in pancreatic surgery.

Carl Gussenbauer (1842-1903), known for many contributions to surgery, should also be noted prominently in the list of pioneers of pancreatic surgery. His successful performance of external drainage for a pancreatic cyst in 1882 was the first planned pancreatic operation. Although pancreatic surgery had been developed in animal models during the seventeenth century, surgery of the human pancreas was practically nonexistent owing to the dismal results seen with incidental pancreatic operations done early in the nineteenth century. Gussenbauer's procedure was a significant advance, representing a safe and effective solution to the pancreatic cyst problem. Gussenbauer's external drainage procedure remained the gold standard for treating pancreatic cysts until the 1920s and was still a widely practiced therapeutic option until the 1950s. With his discipline, insight, and innovative thought, Gussenbauer initiated the modern era of pancreatic surgery.

Austria↗
PubMed2003

Outcome after lateral pancreaticojejunostomy in patients with chronic pancreatitis associated with pancreas divisum.

In order to evaluate surgical outcome after lateral pancreaticojejunostomy (LPJ) in patients with pancreas divisum (PD), we compared the operative results in patients who underwent LPJ for PD with those who underwent LPJ for other causes of chronic pancreatitis. The records of 129 patients who underwent LPJ for chronic pain associated with chronic pancreatitis from 1995 through 2001 were retrospectively reviewed and analyzed. There were 21 patients (11 men, 10 women, mean age 40 years) who had PD as a cause of chronic pancreatitis. The remaining 108 patients (58 men, 50 women, mean age 48 years) had chronic pancreatitis of other etiologies. The two groups had a similar stage of disease progress measured by incidence of pancreatic duct strictures, terminal biliary stenosis, pseudocysts, insulin dependency, need for pancreatic enzymes, and symptom duration. There was no difference in operative time (200 +/- 13.3 vs. 206 +/- 6.1 minutes) or intraoperative blood loss (200 vs. 300 mL) comparing the PD to the other group. The overall postoperative morbidity (14% vs. 23%) and mortality (0% vs. 2%) were not significantly different in PD versus other group comparison. Hospital length of stay was similar in both groups (7.0 +/- 2.4 vs. 8.0 +/- 1.3 days). In the PD group 10 per cent required reoperation with pancreatic resection for failure of LPJ to improve chronic pain versus 9 per cent in the other group. Comparison of patients who undergo LPJ for PD with those who undergo LPJ for other etiologies showed no significant difference in failure rates as measured by the need for reoperation. Postoperative morbidity and mortality were similar in both groups. Failure of LPJ in patients with PD may be related to factors associated with failure of LPJ in management of chronic pancreatitis of other causes. This includes inadequate drainage of the head of gland, failure to drain small ducts, and perineural inflammation.

Adolescent↗
PubMedDate not supplied

Do preoperative pancreatic stents increase operative morbidity for chronic pancreatitis?

BACKGROUND/AIMS: Recent studies suggest that preoperative placement of bile duct stents increases morbidity after pancreatic surgery. The influence of pancreatic duct stenting on outcome after pancreatic surgery is unknown. METHODOLOGY: The records of 264 consecutive patients who underwent lateral pancreaticojejunostomy, pancreaticoduodenectomy, or distal pancreatectomy for chronic pancreatitis were retrospectively reviewed and analyzed. RESULTS: There were 137 patients who received preoperative endoscopic pancreatic stents. The remainder underwent preoperative ERCP without stent placement. Both groups had a similar stage of disease measured by endoscopic, clinical, and histological findings. The overall postoperative morbidity was higher in the stent group (19.7% vs. 42.3%, p<0.001, odds ratio 3.0). Intra-abdominal complications occurred more frequently in the stent group (10.2% vs. 32.8%, p<0.001), including a difference in pancreatic leaks. There was no difference in extra-abdominal complications (10.2% vs. 13.1%) and mortality (1.6% vs. 1.5%). CONCLUSIONS: Patients who undergo pancreatic duct stenting and require surgical drainage at a later point have a threefold increased risk for peri-operative complications. An increase in intra-abdominal complications might be related to stent associated pancreatic duct injuries, stent occlusion, and bacterial colonization of the stent.

Adolescent↗