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Objective: Exposure to radiation doses above 2 Gray (Gy) can cause skin burns. There is also a lifetime cancer risk of ≈5.5% for every Sievert (Sv) of radiation. We assessed the radiation burden associated with endovascular treatment of the aorta., Method: Thoracic (TEVAR), Infra-renal (IEVAR) and branched/fenestrated (BEVAR/FEVAR) endovascular aortic repairs were studied. The prospectively recorded dosimetric parameters included: fluoroscopy time and dose area product (DAP). Exposure films, placed underneath 10 patients intra-operatively, recorded skin dose and were used to calculate skin (Gy) and tissue (Sv) doses., Results: The TEVAR cohort (n = 232) were younger (p < 0.0001) than BEVAR/FEVAR (n = 53) and IEVAR (n = 630). The median DAP was higher (p = 0.004) in the BEVAR/FEVAR group compared with IEVAR and TEVAR: 32,060 cGy cm(2) (17,207-213,322) vs 17,300 cGy cm(2) (10,940-33,4340) vs 19,440 cGy cm2 (11,284-35,101), respectively. The equivalent skin doses were BEVAR/FEVAR: 1.3 Gy (0.71-8.75); IEVR: 0.71 Gy (0.44-13.7); TEVAR: 0.8 Gy (0.46-1.44). The whole body effective doses were BEVAR/FEVAR: 0.096 Sv (0.052-0.64); IEVR: 0.053 Sv (0.033-1.00); TEVAR: 0.058 Sv (0.034-0.11)., Conclusions: The radiation exposure during endovascular aortic surgery is relatively low for the majority but some patients are exposed to very high doses. Efforts to minimise intra-operative exposure and graft surveillance methods that do not use radiation may reduce the cumulative lifetime malignancy risk., (Copyright © 2012 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

Purpose: To achieve clinical validation of cutoff values for newborn screening by tandem mass spectrometry through a worldwide collaborative effort., Methods: Cumulative percentiles of amino acids and acylcarnitines in dried blood spots of approximately 25–30 million normal newborns and 10,742 deidentified true positive cases are compared to assign clinical significance, which is achieved when the median of a disorder range is, and usually markedly outside, either the 99th or the 1st percentile of the normal population. The cutoff target ranges of analytes and ratios are then defined as the interval between selected percentiles of the two populations. When overlaps occur, adjustments are made to maximize sensitivity and specificity taking all available factors into consideration., Results: As of December 1, 2010, 130 sites in 45 countries have uploaded a total of 25,114 percentile data points, 565,232 analyte results of true positive cases with 64 conditions, and 5,341 cutoff values. The average rate of submission of true positive cases between December 1, 2008, and December 1, 2010, was 5.1 cases/day. This cumulative evidence generated 91 high and 23 low cutoff target ranges. The overall proportion of cutoff values within the respective target range was 42% (2,269/5,341)., Conclusion: An unprecedented level of cooperation and collaboration has allowed the objective definition of cutoff target ranges for 114 markers to be applied to newborn screening of rare metabolic disorders.

Objective: The precision grip-and-lift task (PGLT) has been used to measure hand motor coordination in PD. We designed this study to investigate if the PGLT outcome variables correlate with the UPDRS motor scores and if all PGLT outcome variables are "responsive" to levodopa., Methods: We used PGLT to assess hand motor coordination in 10 PD and 10 normal controls before and after levodopa., Results: Factor analysis showed that the six PGLT parameters were reduced to two factors, a levodopa-responsive factor and a dopa-resistant factor that explained 74% of the total variance. The levodopa-responsive factor, which correlated significantly with "off" UPDRS motor scores, includes load preparation time, maximum vertical acceleration, maximum grip velocity and maximum grip force. The levodopa-resistant factor, which did not correlate with "off" UPDRS motor scores, included maximum negative load force and tremor during lift. Both dopa-responsive and dopa-resistant factors were altered in PD compared to controls before levodopa. Levodopa improved dopa-responsive, but not dopa-resistant factor in PD., Conclusions: PGLT can measure two aspects of fine motor performance, both affected by PD but differentially affected by levodopa., Significance: PGLT can be useful in characterizing the response of motor abnormality in PD therapeutic trials.

Objective: Normative data on transcranial magnetic stimulation (TMS)-derived measures of cortical excitability in the elderly is sparse. Nevertheless, elderly subjects are included as controls in studies utilizing TMS to investigate disease states. Age-associated increased ventricular cerebrospinal fluid CSF (vCSF) and white matter hyperintensity (WMH) MRI volumes have uncertain significance in non-demented elderly. Information regarding cortical excitability in neurologically intact elderly would augment our understanding of the pathophysiology of aging and assist in the interpretation of TMS studies involving elderly subjects., Methods: Twenty-four healthy elderly subjects underwent TMS testing to determine outcomes of resting motor threshold (RMT) cortical silent period (cSP) and central motor conduction time for examination in relation to WMH, vCSF, and CNS volumes., Results: Increased vCSF and WMH volumes were associated with decreased right and left hemisphere RMT. Smaller CNS volumes were associated with decreased right hemisphere RMT and shorted cSP., Conclusions: Commonly observed age-associated MRI changes are associated with findings consistent with increased cortical excitability., Significance: Age-related MRI findings likely reflect changes at a cellular level, and may influence cognitive and motor integrity in the elderly. Future TMS studies investigating cortical excitability may wish to consider neuroimaging markers of neurodegeneration prior to enrolling elderly subjects as controls.

The effects of the anti-marine-borer timber preservative CCA (a pressure impregnated solution of copper, chromium and arsenic compounds) on early fouling community formation were investigated during a number of field trials. The formation of a biofilm on the surface of CCA-treated and untreated timber panels of Scots pine was examined by scanning electron microscopy following submersion in Langstone Harbour, Portsmouth, UK for periods of 2, 7, 14 and 28 days. Results indicated a slightly faster rate of biofilm formation after 2 and 7 days of exposure on untreated timber compared to CCA-treated timber, although no differences were visible between panels after 14 and 28 days exposure, or between panels treated to different CCA loadings after all exposure periods. Settlement of the serpulid Ficopomatus enigmaticus and two species of barnacles (Elminius modestus and Balanus crenatus) onto the surface of untreated and CCA-treated panels of Scots pine was examined following 4 weeks exposure in a brackish water millpond at Emsworth, West Sussex. Numbers of individuals were higher on CCA-treated panels than on untreated panels, and in the case of F. enigmaticus abundance of individuals increased with increasing preservative loadings. Early colonization by macroalgal species on the surface of CCA-treated and untreated panels of Scots pine was examined following submersion of panels in Langstone Harbour for a period of 4 weeks. Percentage cover of most species of algae was similar on the surface of CCA-treated and untreated panels, with the exception of Hincksia granulosa and Ceramium nodulosum which had significantly higher percentage cover on untreated panels. Possible explanations for the recruitment patterns are discussed.

The effect of the anti-marine-borer timber preservative chromated copper arsenate (CCA) (a pressure impregnated solution of copper, chromium and arsenic compounds) on non-target marine fouling animals was investigated during a subtidal exposure trial. Panels of Scots pine treated to target retentions of 12, 24 and 48 kg CCA per m-3 of wood, plus untreated controls were submerged at a coastal site on the south coast of the UK for 6, 12 and 18 months. After each exposure period the fouling communities that formed on the surface of panels were assessed both qualitatively and quantitatively. Community structure was similar on panels treated to the three CCA loadings, but was significantly different from community structure on untreated panels. The total number of species (species richness) was similar on all panels, although the number of individual organisms attached to the surface of panels was significantly higher on CCA-treated panels than on untreated panels. k-dominance curves revealed that the difference in numbers of individuals between CCA-treated and untreated panels was caused by higher numbers of the dominant species (Elminius modestus, Hydroides ezoensis, and Electra pilosa) on CCA-treated panels. Other species were present in similar numbers on panels of all treatments. Results indicate that there are no detrimental toxic effects to epibiota caused by the presence of CCA preservative within the matrix of the wood at any of the treatment levels. Differences in community structure between CCA-treated and untreated panels may be due to enhanced larval settlement on CCA-treated timber by some species as a result of modifications to the surface properties of the timber by the CCA preservative.

The ultimate effectiveness of an arthroplasty is most accurately determined by a long-term review of the joints' function and freedom from pain. We examined 17 patients an average of 11.5 years (range, 4-26 years) following volar plate arthroplasty for a fracture-dislocation of the proximal interphalangeal joint. All surgeries were performed by the same surgeon. The average age was 36 years (range, 17-61 years). No patient complained of pain at rest or with activity. Patients having arthroplasty within 4 weeks of injury attained a total active range of motion of 85 degrees (50 degrees to 110 degrees ). Patients having arthroplasty more than 4 weeks after injury (average, 20 weeks) included several elderly women and averaged 61 degrees (30 degrees to 90 degrees ) total active range of motion. Four patients showed some degree of joint narrowing at the follow-up examination. This review suggests that volar plate arthroplasty continues to be of benefit on a long-term basis and provides satisfactory function and pain-free motion.

It has been hypothesized that instability of the thumb trapeziometacarpal joint is a major factor in the etiology of degenerative disease. Theoretically, surgically stabilized joints should be subject to less shear force and, hence, will be less likely to develop degenerative changes. The long-term results of volar ligament reconstruction were assessed in 19 patients (24 thumbs). The average age at surgery was 33 years (range, 18-55 years). Twenty-three thumbs were radiographic stage I; a preoperative x-ray was not available in 1. The follow-up period averaged 15 years (range, 10-23 years). At the final follow-up visit 15 thumbs were stage I, 7 were stage II, and 2 were stage III. Fifteen patients were at least 90% satisfied with the results of the surgery. Only 8% of thumbs advanced to radiographic arthritic disease, which compares favorably with the 17% to 33% reported incidence of stage III/IV basal joint arthritis in the general population., (Copyright 2000 by the American Society for Surgery of the Hand.)

Nineteen patients with chronic scaphoid nonunion and associated degenerative arthritis between the distal fragment and the radial styloid were treated by resection of the distal fragment. All patients had a dorsal intercalated segment instability wrist collapse pattern with an average radiolunate angle of -32 degrees and a 10% reduction in the carpal height, both of which changed minimally during the follow-up period. The duration of the nonunion averaged 12 years and the follow-up period averaged 49 months. Range of motion improved 85% and grip improved 134%. Thirteen of the patients experienced complete pain relief. One patient required additional surgery and elected wrist arthrodesis. Resection of the distal fragment is not recommended for patients with capitolunate arthritis. Two of the 4 patients with capitolunate arthritis had persistent symptoms; 3 had progressive degenerative changes.

Although much has been written about surgical treatment of arthritis of the first carpometacarpal joint, no literature exists on splinting as a conservative treatment. One hundred fourteen patients (130 thumbs) were retrospectively reviewed to determine the efficacy of splinting. Patients were grouped according to their stage of disease and whether they had carpometacarpal joint surgery. Seventy-six percent of patients with stage I and II disease and 54% of patients with stage III and IV disease had improvement in their symptoms with splinting. There was no significant difference in the degree of improvement between the 2 groups. All patients who had initial improvement in their symptoms with splinting had between 54% and 61% average improvement in symptom severity 6 months after splinting. All groups were found to be equally tolerant of the splinting protocol and no group had a significantly higher rate of activity modification. Overall, splinting was found to be a well-tolerated and effective conservative treatment to diminish, but not completely eliminate, the symptoms of carpometacarpal joint arthritis and inflammation.

The presence of palpable thickening and maintenance of stability within weeks of total excision of the proximal interphalangeal (PIP) joint collateral ligaments is an established, although somewhat mysterious, phenomenon. To further investigate this postoperative thickening, magnetic resonance imaging (MRI) scans were obtained on 10 joints in 9 patients who had undergone total ligament excision for posttraumatic stiff PIP joints 3 months to 14 years earlier. Although the ultrastructure of these newly formed structures is yet unknown, their palpable consistency, MRI contour, distribution, and signal intensity suggest the formation of a new soft tissue structure, albeit scar, which has all the attributes of a collateral ligament. This MRI of a "neocollateral ligament" would help explain the consistent observation of complete joint stability within weeks following total excision of both PIP joint collateral ligaments. All patients from the 14-year span sampled were found to have a similar, consistent, linear low signal density structure crossing the joint margins and essentially identical to that of a normal collateral ligament.

Twenty patients with symptomatic stage IV basal joint (pantrapezial) arthritis were treated with double interposition arthroplasty, a new technique that resurfaces the degenerative trapeziometacarpal and scaphotrapezial joints after minimal distal trapezial resection. The results of the 21 procedures were reviewed clinically and radiographically after a mean follow-up period of 34 months (minimum, 1 year). Ninety-one percent of the patients were completely satisfied. Seventy-one percent were entirely free of pain, and an additional 24% noted only occasional, mild, high-stress pain that did not limit their activities. One case was a clinical failure. Objectively, all 21 basal joints were stable, with active range of motion to within 90% of normal. Mean grip strength increased 32%, from a force of 26.1 kg to 33.9 kg (p < .01). Key pinch strength increased from a force of 5.3 kg to 6.0 kg (an 11% increase; p = .05). A new method of determining changes in basal joint height indicated a mean decrease in height of 5.3% (range, 0%-12%) at rest and 8.1% (range, 0%-20%) under axial compression. This difference was statistically but not functionally significant. Overall, there were 95% good or excellent results and 1 poor result. We believe this technique is simple and preserves the osseous foundation of the basal joints. These results compare favorably with arthroplasties that include trapezium excision for the treatment of stage IV basal joint arthritis.

Twelve patients who had undergone proximal row carpectomy with partial resection of the capitate were reviewed. Ten patients had degenerative arthritis secondary to scapholunate advanced collapse deformity or chronic scaphoid nonunion. Seven of these patients had significant lunocapitate and three had radiolunate degenerative disease. An additional two patients underwent an immediate modified proximal carpectomy for acute complex radiocarpal trauma. At follow-up evaluation after a mean of 55 months, seven patients reported no pain and four patients had only occasional pain with strenuous activity. There was a trend toward increase of the total active flexion/extension arc, from 80 degrees before to 94 degrees after operation. The improvement in flexion from 38 degrees to 46 degrees was significant (p = .01). In the final four patients, who also had interposition of the dorsal capsule, however, the final arc of motion averaged 111 degrees. Grip strength improved from 19 to 26 kg following surgery. This strength gain was statistically significant (p = .01 by paired t-test analysis). The favorable results of this partial capitate resection technique may be due to a broader distribution of radiocarpal compression forces. Interposition of the thickened dorsal capsule may also contribute to an improved radiocarpal interface. The intermediate-term results of this review would suggest that lunocapitate and radiolunate disease need not contraindicate a modified proximal row carpectomy.

Vascular leiomyomas or angioleiomyomas are benign solitary smooth muscle tumors that occur uncommonly in the hand. The peak incidence is in the third to fifth decades of life, and men are more often affected than women. This tumor is rarely diagnosed before surgery. The usual treatment is simple excision of the mass and ligation of feeder vessels. Although the tumors occur anywhere in the hand, there are only two previous cases of vascular leiomyoma involving the digital artery. A recent case of this tumor involving a digital artery documented by arteriography and treated by excision of the mass and end-to-end anastomosis of the artery is presented. The authors review their experience with vascular leiomyomas in the hand and present four cases along with a review of 105 cases found in the English literature.

The classic dopamine agonist apomorphine, microinjected into the medial preoptic area (MPOA), enhances the copulatory behavior of male rats, while pharmacological blockade of endogenous dopamine inhibits sexual behavior. We now report that MPOA injections of 10 micrograms of the selective D1 agonist dihydroxyphenyl-tetrahydrothienopyridine (THP) significantly increased the number of ejaculations, while decreasing the latency to ejaculate in a 30-min test. These effects were not observed following coadministration of the selective D1 antagonist SCH-23390 with 10 micrograms THP. This enhancement may be related to a D1-stimulated facilitation of penile erections.

The complete excision of scarred proximal interphalangeal collateral ligaments as the cornerstone of surgical treatment for proximal interphalangeal joint contractures was evaluated. Supplemental palmar plate distal release, extensor tenolysis, and flexor sheath release were performed as needed. Sixteen patients with primary proximal interphalangeal joint contractures treated by this method were reviewed with the use of preoperative data obtained from chart review and postoperative data from direct patient examination. The average range of motion increased from 38 degrees to 78 degrees. No patients had instability of the proximal interphalangeal joints on manual testing and x-ray examination. This radical surgical approach to contracted proximal interphalangeal joints is justified by the improved range of motion without instability.

Dopamine (DA) metabolites in microdialysates from the medial preoptic area (MPOA) of male rats increased during copulation. These increases were not observed during eating of a highly palatable food, or if the animal failed to copulate, or if the microdialysis probe was anterior or dorsal to the MPOA. The only two animals with measurable serotonin (5-HT) levels while the female was present were also the only two that either failed to copulate or copulated but failed to ejaculate. These data are consistent with previous evidence for a facilitative role of MPOA DA in the control of male sexual behavior; however, 5-HT activity in the MPOA may impair copulation.

Visualization of the scaphotrapezial joint during basal joint arthroplasty has been recommended to establish the stage of degeneration. This study attempts to clarify that recommendation and evaluate whether moderate wear of the joint precludes a good result of trapeziometacarpal hemiarthroplasty. To assess the need for inspection of the scaphotrapezial joint, x-ray films, tomograms, and operative findings in 23 cases of basal joint arthroplasty were reviewed. X-ray findings agreed with operative findings at the scaphotrapezial joint in only 76% of the cases. We also evaluated 18 thumbs in 15 patients who underwent interposition arthroplasty of the trapeziometacarpal joint and at surgery had moderate degenerative changes of the scaphotrapezial joint. The scaphotrapezial joints were left intact and the trapeziometacarpal joints were reconstructed. Follow-up averaged 8 years. In no case was there x-ray or symptomatic progression of the disease at the scaphotrapezial joint. Clinically, 78% were rated excellent, 17% good, and 5% fair.

Dopamine D1 and D2 receptors may synergize with or oppose each other's effects. We suggest that stimulation of D1 and D2 receptors in the medial preoptic area (MPOA) of male rats have opposing effects on genital reflexes. In Experiment 1 a D1 agonist injected into the MPOA increased the number of ex copula erections but decreased the number of seminal emissions. In Experiment 2 a D1 antagonist had the opposite effects (decreased erections and increased seminal emissions), as had a D2 agonist previously. We also suggest that D1 and D2 mechanisms in the MPOA have different thresholds of activation. In Experiment 3 a low dose of the mixed D1/D2 agonist apomorphine increased erections and anteroflexions, an effect blocked by the D1 antagonist. In Experiments 3 and 4 a high dose of apomorphine increased seminal emissions, an effect blocked by the D2 antagonist. Thus, low levels of dopaminergic stimulation may facilitate erections and anteroflexions (controlled by the parasympathetic system and striated muscles) via D1 receptors; higher or more prolonged stimulation may shift to seminal emission (controlled by the sympathetic system) via D2 receptors. This may explain the progression from erectile to ejaculatory mechanisms during copulation.

Thirty-three patients with pain and decreased range of motion after traumatic derangement of the distal radioulnar and ulna-carpal joint were treated with a modified Darrach distal ulnar resection. Their ages ranged from 22 to 75 years (average, 50 years). Twenty-seven patients had Colles' or other distal radius fractures. Seven patients had ulnar resection for treatment of distal ulnar-carpal derangement. Follow-up averaged 54.4 months. The patients showed an average increase in extension of 58% and flexion increased by 40% (p less than 0.01). Pronation increased by 40% and supination increased by 60% (p less than 0.01). Average grip strength increased by 38% (p less than 0.05). Ninety-one percent good or excellent results were achieved with this procedure. The Darrach resection can predictably provide pain relief while improving strength and motion when attention is paid to minimal bony resection and meticulous soft tissue reconstruction.

The D2 dopamine receptor agonist quinelorane (LY-163502), microinjected into the paraventricular nucleus (PVN), affected genital response of restrained supine male rats in a biphasic dose-dependent fashion. A moderate dose (1 microgram) facilitated penile responses (intense erections and penile movements), and decreased the latency to the first response. A high dose of quinelorane (10 micrograms) facilitated seminal emission while inhibiting penile responses. The addition of the D1 antagonist SCH-23390 to the 1 microgram dose of quinelorane potentiated quinelorane's increase in seminal emission. We suggest that D1 receptors in the PVN may be antagonistic to D2 receptor-mediated seminal emission, and possibly also penile responses. In copulation tests 1 microgram quinelorane decreased mount latency, whereas 10 micrograms quinelorane increased mount and intromission latencies and slowed copulatory rate. Both 1 and 10 micrograms quinelorane, and also 1 and 10 micrograms of the mixed D1 and D2 agonist apomorphine, decreased the number of intromissions preceding ejaculation.

This study investigated the effects on genital reflexes of unilateral MPOA injections of 0.1, 1, 3, and 10 micrograms of the D2 agonist quinelorane (LY-163502), and of 3 micrograms quinelorane administered together with 3 micrograms of the D1 antagonist SCH-23390. In addition, the effects of an MPOA injection of 10 micrograms apomorphine were tested. All but the lowest dose of quinelorane significantly decreased the latency to the first reflex. The 3 and 10 micrograms doses of quinelorane, and the combination of quinelorane and SCH-23390, decreased the total number of reflexes. In addition, 10 micrograms quinelorane increased the number of seminal emissions. 10 micrograms apomorphine, like 10 micrograms quinelorane, decreased the latency to the first reflex and increased the number of seminal emissions, but did not decrease the numbers of erections or penile movements. The ratio of D1/D2 activity may influence the number of erections displayed during ex copula testing.

Exposure to thyroid hormone (T4) has been known to affect the plasma triglyceride (TG) as well as the plasma cholesterol level, but the mechanisms and degree of response in genetic hyperlipidemic states have not been defined. In the present study, we examined TG secretion and removal in vivo in genetically hyperlipemic Zucker rats maintained in hypothyroid, euthyroid, and hyperthyroid states for 6 weeks. The induction of the hypothyroid state resulted in marked weight loss with reduced food intake, and a parallel reduction in plasma TG concentration, hepatic TG production, and peripheral TG removal. In contrast, a similar degree of weight loss in the hyperthyroid state was associated with increased food intake, but no significant reduction in plasma TG concentration, production, or clearance. The changes in plasma cholesterol concentration in the hyperthyroid state were striking, with a 94% reduction in LDL cholesterol, but only a minimal reduction in the HDL cholesterol level. The hypercholesterolemic state in the Zucker rat. The results suggest that the very low density lipoprotein TG metabolism is influenced by hypothyroid but not the hyperthyroid state in this model of human genetic Type IV hyperlipemia. The primary reduction in LDL relative to HDL in response to thyroxine excess, suggests a therapeutic potential in disorders of genetic hyperlipidemia.

Previous studies have shown that systemic administration of the dopamine agonist apomorphine produced a biphasic effect on erection in the freely moving rat, with lower doses facilitating, and high doses inhibiting, erection. However, those studies did not distinguish between erection per se and seminal emission. The present results demonstrate that apomorphine produces a similar biphasic effect on penile reflexes in the restrained, supine rat, while facilitating seminal emission in a monophasic fashion. Haloperidol, a centrally-acting dopamine antagonist, either blocked the effects produced by apomorphine administration, or had actions opposite to those of apomorphine. Domperidone, a dopamine antagonist that does not readily penetrate the blood-brain barrier, did not antagonize apomorphine's effects, and did not affect penile responses when administered alone. These results suggest that dopamine receptors in the central nervous system regulate genital responses, and that effects on penile reflexes and seminal emission can be experimentally dissociated.

The accuracy of radiographic evaluation of the pantrapezial joints and the anatomic incidence of pantrapezial arthrosis, were studied by comparing radiographs with anatomic dissections of 68 cadaver hands. When the trapezium-thumb metacarpal joint demonstrated degenerative changes, multitrapezial joint changes were noted in 73% radiographically, but in only 46% anatomically. The major reason for this discrepancy was a radiographic misinterpretation of the nature of osteophytes near the trapezium-index metacarpal joint. Anatomic changes of degenerative joint disease were noted in 60% of the trapezium-thumb metacarpal joints and 34% of the trapezium-scaphoid joints. Degenerative joint changes were rare in the trapezium-index metacarpal and trapezium-trapezoid joints. Routine anteroposterior, lateral, and oblique radiographs of the hand cannot be depended upon to provide adequate visualization of all the trapezial joints.

This study examines insulin and glucagon secretion in the basal state and in response to clofibrate therapy in patients with angiographically proven coronary artery disease. When compared with weight matched subjects without coronary artery disease, neither insulin nor glucagon secretion were abnormal in response to L-arginine stimulation. However, in response to clofibrate, a marked reduction in insulin secretion and simultaneous elevation in glucagon secretion characterized all patients. Our data suggest the hypothesis that altered insulin and glucagon secretion in response to clofibrate therapy may participate in the reduction of new coronary events reported to occur during therapy with this drug.

The relationship between plasma lipoprotein concentration and histologic myointimal proliferative lesions in the coronary vessels was examined in 37 freshwater Chinook salmon (Oncorhynchus tshawytscha). The fish were obtained during the migrating, schooling, and spawning periods of the fourth year of life. Plasma apoB polypeptides were maximally elevated in the migrating fish in correlation with a high degree of coronary vascular disease. Both the relative incidence and the severity of lesions were greater in migrating salmon as compared with spawning fish. In contrast, plasma apoA polypeptides were maximally elevated in association with reduced levels of plasma apoB in spawning fish in which coronary lesions were reduced in severity and incidence. Simultaneous observations confirmed the relative decrease in circulating thyroid hormone and increase in adrenal cortical hormones characteristic of the maturation process. These data in the mature freshwater Lake Michigan Chinook salmon provide direct support for the hypothesis that coronary proliferative atherogenesis proceeds in parallel with excessive exposure to apoB-containing lipoproteins and that reversal is associated with excessive exposure to apoA-containing lipoproteins. The temporal relationship to altered hormone status is described, but the pathophysiologic significance for atherogenesis cannot be determined from these data.

To investigate the participation of the major apoprotein involved in triglyceride transport in the pathogenesis of endogenous hypertriglyceridemia, five kinetic studies of apoprotein B were conducted in volunteer normolipidemic subjects and six studies in four patients with endogenous hypertriglyceridemia. The transport of apoprotein B within four kinetic subclasses of very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL), and low density lipoprotein (LDL) was studied by injection of [75Se]selenomethionine. A 24-fold increase in the entry of newly synthesized apoprotein B at the initial kinetic subclass of the four-compartment VLDL delipidation sequence characterized the hypertriglyceridemic studies relative to normal subjects. Moreover, approximately 75 mg/kg per day of VLDL-B turnover reflected direct catabolism independent of conversion to IDL and/or to LDL, in contrast to the 8 mg/kg per day observed in controls. IDL-B was derived from VLDL-B in both normal and hypertriglyceridemic subjects, and was responsible for greater than 70% of all LDL-B synthesis. LDL-B pool size and turnover were indistinguishable in hypertriglyceridemic subjects from that observed in normal subjects. These studies suggest that two kinetic phenomena may characterize the pathophysiology of endogenous hypertriglyceridemia: a) over-production of apoB within a kinetic subclass of VLDL and b) preferential catabolism of hypertriglyceridemic VLDL without prior conversion to IDL/LDL.

Twenty patients were evaluated up to 9 years (average, 3.8 years) after a hemiscaphoid fascial arthroplasty. All were men. Twelve had a chronic scaphoid nonunion, six had radioscaphoid arthritis from chronic scapholunate advanced collapse deformity, and two had irreducible transscaphoid perilunate dislocations. The degenerated or impinging portion of the scaphoid was replaced by a slightly oversized fascial implant; 4 being constructed of autograft and 16 of allograft fascia. Postoperative motion included a 30 degree or 73% gain in extension and a 19 degree or 38% gain in flexion, producing an overall 140 degree average arc motion. Grip strength increased 17% after operation. Pain was completely or dramatically relieved in all but one patient. All other patients returned to their preoperative occupations.

In 10 years 24 patients had a volar plate advancement arthroplasty for acute or chronic fracture dislocations of the proximal interphalangal joint. Seven were done within 6 weeks of injury, 17 at 6 weeks to 2 years following injury. Final ranges of motion averaged 95 degrees for the former and 78 degrees for the latter group. Radiographs frequently demonstrated a marked remodeling of the disrupted contour of the joint surface of the middle phalanx.

Seventeen hyperlipemic and 17 normolipemic littermate Zucker rats were treated with clofibrate or normal saline to determine the effect of this drug upon hepatic triglyceride (TG) production and peripheral TG disposal. Peripheral Intralipid clearance was not different in hyperlipemic rats relative to control animals. Hyperlipemic animals demonstrated abnormally elevated TG production in the fasted state which was not corrected with clofibrate administration. Following treatment, peripheral Intralipid clearance was increased 100% in hyperlipemic rats, but unchanged in normolipemic animals. These observations provide further evidence that the predominant lipid reducing action of clofibrate is manifested only in the hyperlipemic state, and predominantly upon peripheral lipid disposal.

The posttraumatic syndrome of Volkmann's ischemia and infarction is the end result of compromise of muscle perfusion within the osteofascial compartments of the forearm. The "closed space" arrangement as well as the particular neurovascular anatomy make the flexor forearm muscles particularly susceptible to the cyclic derangement of blood flow, which ultimately results in muscle ischemia and infarction. Only strong clinical awareness will allow appropriate early diagnosis and treatment by surgical decompression. Fasciotomy and epimysiotomy serve to interrupt the cycle. The successful treatment of Volkmann's ischemia requires an understanding of the pathophysiologic mechanisms at work, an appreciation of the subtleties of the clinical presentation, and strong grounding in the details of forearm anatomy and techniques of surgical decompression.

Displaced fractures of the shaft of the proximal phalanx can lead to marked deformity and disability when poor results are obtained. Despite the attention popular concepts of open reduction and internal fixation have received, a less invasive technique has been our standard approach. A prospective study of closed reduction and percutaneous Kirschner wire fixation in 100 consecutive fractures yielded good or excellent results in 90% of cases when treated within 5 days of injury.

The present investigation was designed to examine the influence of genetic Type IV hyperlipoproteinemia on the metabolism of lipids in response to estrogen exposure. The influence of 17-Beta-estradiol * was examined in a dose-response study over a range of hormone concentration from 10 to 100 pg/ml in genetic hyperlipidemic Zucker rats. In oophorectomized female rats, replacement levels of plasma estradiol of 40 pg/ml resulted in maximal hypertriglyceridemia of approximately 500 mg/dl representing a 5-fold exaggeration of that observed in control genetically norm-lipemic animals. This hypertriglyceridemia was associated with an increased production of triglyceride (TG) in excess of clearance, with a resulting production: clearance ratio of approximately 1.5. Exposure to maximum blood levels of estradiol, approximately 100 pg/ml, resulted in sub-normal levels of plasma TG (-145 mg/dl) in association with a reduced production: clearance ratio of approximately 0.36. In contrast to the marked hypocholesterolemic response to maximum estrogen exposure seen in normolipemic animals, the genetic Type IV hyperlipemic animal failed to demonstrate reduced plasma cholesterol concentration. This phenomenon was related to a rise in plasma LDL concentration in conjunction with parallel reduction in plasma HDL2 levels.Thus, an abnormal ratio of excessive LDL: HDl emerged in response to estrogen exposure in this model of human Type IV lipemia. This observation suggests that the genetic predisposition of the host may be critical to both the quantitative as well as the qualitative response to estrogen.

The construction and subsequent evaluation of an apparatus for the detection of trace amounts of nitrosamines is described. The apparatus consists of a gas chromatograph, a catalytic chamber to generate nitric oxide from eluted nitrosamines, and a chemiluminescent detector to measure the infra-red emission resulting from interaction of this gas with ozone. Examples of the use of the system for determining the nitrosamine concentration in food extracts and other materials are given.

An extra-articular ligament reconstruction to stabilize the thumb carpometacarpal (CMC) (basal) joint by routing a portion of the flexor carpi radialis (FCR) through the base of the thumb metacarpal has been performed on more than 100 patients since 1967. This study reviews the first 50 consecutive reconstructions with an average follow-up of 7 years. Intractable pain was the primary indication for surgery. Each joint was examined both pre and postoperatively and rated as a stage I through stage IV according to the radiographic appearance. Of the patients with zero or minimal articular changes (stages I and II), 95% achieved good or excellent results because of having little or no postoperative pain. Of the patients with moderate to advanced degenerative changes (stages III and IV), 74% achieved good or excellent results. All stage I cases and 82% of stage II cases were free of recognizable degeneration on follow-up radiographs up to 13 years postoperatively. These findings suggest that ligament reconstruction that is now recommended only for stage I or stage II disease will restore stability, reduce pain, and possibly even retard joint degeneration in a large proportion of patients with painful instability of the thumb CMC joint.

Six subjects with heterozygous familial hypercholesterolemia (FH) (three males, three females) formed the basis for an investigation of the pathways of production of apoprotein B within plasma low-density-lipoprotein (LDL-apoB). Following the intravenous injection of [75Se]selenomethionine as an amino acid tracer, incorporation of the radioactive isotope into the putative precursor of LDL, intermediate density lipoprotein (IDL-apoB), was examined over a 9-day period. The resulting tracer data provided the precursor profile for both the IDL catabolic conversion of LDL as well as for direct synthesis of LDL from amino acids. The fractional conversion rates, (beta) for IDL and (alpha) for amino acids to LDL-apoB, were determined utilizing the two-compartment model for LDL involving both the intravascular and the extravascular pools of apoB. This LDL model was resolved analytically and the parameters alpha and beta were determined so as to give the least squares fit to the LDL tracer data. In this solution, the fractional conversion rates of IDL and of amino acids to LDL-apoB were resolved with a mean fractional residual of 20 +/- 6%, which was randomly distributed within the LDL-apoB data throughout the 216 hours of the studies. The steady-state determination of the pathways of LDL-apoB synthesis, based upon this tracer analysis, indicate that IDL accounts for 46%, and amino acids account for 54% of total apoB production within plasma LDL in heterozygous FH. In contrast, in normal subjects, IDL accounts for 86% of total LDL-apoB production. Since the IDL catabolic pathway represents the predominant if not exclusive source of LDL in normal man, this demonstration of a major non-IDL source of LDL in FH broadens the understanding of the pathophysiology of human familial hypercholesterolemia.

Thirteen patients had thumb metacarpophalangeal (MP) capsulodesis in conjunction with basal joint arthroplasty. The indication for capsulodesis was an MP hyperextension deformity of at least 30 degrees. The minimum follow-up period was 12 months, and the average follow-up was 39 months. Nine patients had an excellent result, three had a good result, and one patient had a result that was rated as fair. Ten patients had complete correction of the MP hyperextension deformity. The average increase in pinch strength was 50%. This procedure enhances the result of a basal point arthroplasty by improving the transmission of force along the thumb ray and by correcting the metacarpal collapse, which produces dorsal subluxation stress on the metacarpotrapezial joint.

Arthrosis of the trapeziometacarpal joint of the thumb is a predictable sequelae of ligament laxity. A new technique of tendon interposition arthroplasty with ligament reconstruction using the flexor carpi radialis tendon for a painful arthritic trapeziometacarpal joint of the thumb is described. Twenty-one patients had 25 operative procedures; 14 were women and seven were men. All of the patients presented with intractable pain, crepitus, and varying degrees of laxity of the basal joint. Pinch strength was diminished. Follow-up averaged 37 1/2 months. After surgery, 91.7% of patients had good to excellent results, and 56% were completely pain free. Range of motion and grip and pinch strengths were equal on the operated and unoperated sides.

The effect of glucagon on serum lipids and very low density lipoproteins (VLDL) has been examined in the eulipemic and the hyperlipemic rat. An inhibition of amino acid incorporation into hepatic lipoprotein apoprotein was observed, with an associated decrease in circulating VLDL apoprotein, decreased serum triglyceride concentration, and a loss of the pre-beta band as judged by serum lipoprotein electrophoresis. The data suggest that an important action of this hormone is to decrease the synthesis of the protein moiety of the VLDL; this may contribute to the hypolipemic action of glucagon by introducing a limitation in hepatic lipoprotein production.