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We demonstrate the efficacy of a Bayesian statistical inversion framework for reconstructing the likely characteristics of large pre-instrumentation earthquakes from historical records of tsunami observations. Our framework is designed and implemented for the estimation of the location and magnitude of seismic events from anecdotal accounts of tsunamis including shoreline wave arrival times, heights, and inundation lengths over a variety of spatially separated observation locations. As an initial test case we use our framework to reconstruct the great 1852 earthquake and tsunami of eastern Indonesia. Relying on the assumption that these observations were produced by a subducting thrust event, the posterior distribution indicates that the observables were the result of a massive mega-thrust event with magnitude near 8.8 Mw and a likely rupture zone in the north-eastern Banda arc. The distribution of predicted epicentral locations overlaps with the largest major seismic gap in the region as indicated by instrumentally recorded seismic events. These results provide a geologic and seismic context for hazard risk assessment in coastal communities experiencing growing population and urbanization in Indonesia. In addition, the methodology demonstrated here highlights the potential for applying a Bayesian approach to enhance understanding of the seismic history of other subduction zones around the world.

The small Hawaiian sepiolid Euprymna scolopes, with its symbiotic luminous bacterium Vibrio fischeri, was cultured through one complete life cycle in 4 months. Paralarval squid hatchlings were actively planktonic for the first 20-30 days, after which they settled and assumed the typical adult mode of nocturnal activity and diurnal quiescence. Squids were aggressive predators that preferred actively swimming prey up to 2-4 times their size; the only diet that yielded good survival and rapid growth for paralarvae was large adult mysids. Survival to settlement was 73% on this diet, whereas it was 0%-17% on controls and three other diets. Paralarvae initially lacked both detectable luminescence and V. fischeri cells in their incipient light organs; all remaining stages produced luminescence, and their light organs were colonized by apparently pure cultures of > 105 V. fischeri typical of E. scolopes symbiont strains. Survival from settlement to sexual maturity was 76%. Mating and egg laying commenced at 2 months, yet attempts to culture the next laboratory generation of hatchlings were not as successful. The results indicate that the host organism of this symbiosis can soon be cultured with consistency through its brief life cycle, thus opening new avenues of research into developmental aspects of this symbiosis.

The synthesis via anionic polymerization of six linear triblock terpolymers with various sequences of blocks such as PS (polystyrene), PB [poly(butadiene)], PI [(poly(isoprene)] and PCHD [poly(1,3-cyclohexadiene)] is reported. The synthesis of the terpolymers was carried out by the use of anionic polymerization with high-vacuum techniques and sequential monomer addition. Molecular characterization of the samples was performed via size exclusion chromatography (SEC) and membrane osmometry (MO) to measure the polydispersity indices and the number-average molecular weights, respectively. Proton nuclear magnetic resonance spectroscopy ( 1 H NMR) was employed to verify the microstructure type for the polydienes, as well as, to calculate the molar composition. Structural characterization of the terpolymers was performed via transmission electron microscopy (TEM) and small angle X-ray scattering (SAXS), and several morphologies were observed including one which has not been reported previously. Real-space self-consistent field theory (SCFT) without a priori knowledge about the symmetry of the periodic structures was used to elucidate the thermodynamics of the synthesized triblock copolymers.

Polystyrene functionalized at both ends (telechelic polymer) with epoxide groups (epoxy PS epoxy) was reacted with carboxylated multiwall carbon nanotubes (COOH MWNT) in solution in order to graft polymer chains at both ends onto the MWNT surface, forming loops. FT-IR spectroscopy was employed to monitor the formation of aromatic esters and to quantify the amount of telechelic grafted to the nanotube surface as a function of reaction time. When the samples were further annealed in the melt, an increase in the aromatic ester peak was observed, indicating that the unreacted chain ends further grafted to MWNT surfaces to form loops. By reacting the grafted nanotube samples further with monocarboxy terminated poly(4-methylstyrene) (COOH P4MS), the amount of epoxy PS epoxy that had only reacted at one end was determined. Reaction rate analysis indicates that that the grafting of epoxy PS epoxy to the nanotube surface is reaction controlled, as the FT-IR spectroscopy signal grows as a function of approximately t0.3. These studies exemplify how FT-IR spectroscopy can be used as a novel technique to quantify the amount of grafted polymer, grafting rate, and percent of difunctional polymers that form loops, and provide a method to create loop covered nanoparticles.

BACKGROUND.: Alemtuzumab and rabbit antithymocyte globulin (rATG) are commonly used for induction of immunsuppression for kidney and pancreas transplantation, but the two agents have not been compared directly. METHODS.: We conducted a prospective randomized single-center trial comparing alemtuzumab and rATG induction in adult kidney and pancreas transplantation in patients treated with similar maintenance immunosuppression. RESULTS.: Between February 1, 2005, and September 1, 2007, 222 patients randomly received either alemtuzumab (n=113) or rATG (n=109) induction; 180 (81%) underwent kidney alone, 38 (17%) simultaneous pancreas-kidney, and 4 (2%) pancreas after kidney transplants. Of 180 kidney-alone transplants, 152 (84%) were from deceased donors, including 61 (34%) from expanded criteria donors. Retransplantation, human leukocyte antigen match, antibody titer, expanded criteria donors, race, cytomegalovirus status, delayed graft function, and immunologic risks were similar between the two induction groups. With a median follow-up of 2 years (minimum 1 year), overall patient, kidney, and pancreas graft survival rates were 96%, 89%, and 90%, respectively. Survival, initial length of stay, and maintenance immunosuppression (including early steroid elimination) were similar between alemtuzumab and rATG groups, but biopsy-proven acute rejection (BPAR) episodes occurred in 16 (14%) alemtuzumab patients compared with 28 (26%) rATG patients (P=0.02). Late BPAR (>12 months after transplant) occurred in 1 (8%) alemtuzumab patient and 3 (11%) rATG patients (P=NS). Infections and malignancy were similar between the two induction arms. CONCLUSION.: Alemtuzumab and rATG induction therapies were equally safe, but alemtuzumab was associated with less BPAR.

The laparoscopic donor nephrectomy has revolutionized the living donation process for kidney transplantation. Because this surgery is elective and altruistic and smoking has been associated with greater technical difficulty and increased risk for postoperative complications for other types of surgeries, the potential risk of smoking must be addressed with regard to surgical complications. We reviewed 221 laparoscopic kidney donors with known smoking status. Forty-two (19%) were smokers, 39 (18%) were former smokers, and 140 (63%) were nonsmokers. Important donor demographics were similar between groups. There was no difference between the 3 groups for mean operative time (4.5 h vs. 4.6 h vs. 4.4 h), median or mean length of stay (2 days for all groups), estimated blood loss (173+/-137 mL vs. 209+/-184 mL vs. 188+/-198 mL), narcotic use (0.57+/-0.48 mg/kg vs. 0.49+/-0.26 mg/kg vs. 0.53+/-0.36 mg/kg of total 4 morphine equivalents), or postoperative complications. Smoking status does not seem to impact perisurgical patient outcomes in patients undergoing laparoscopic nephrectomies.

The influence of ethnicity on outcome of simultaneous pancreas-kidney transplantation (SPK) is poorly defined. After excluding technical failures, we retrospectively reviewed 96 consecutive SPKs (63 Caucasians [C], 33 African-Americans [AA]). All patients received antibody induction, tacrolimus, mycophenolate mofetil, and steroids. One-, 3-, and 5-year actuarial patient survival was similar between C (98%, 95%, 87%) and AA (90%, 90%, 81%), p=NS. One-, 3-, and 5-year kidney graft survival was similar between C (98%, 86%, 81%) and AA (85%, 85%, 78%), p =NS. One-, 3-, and 5-year pancreas graft survival was significantly worse in AA (71%, 68%, 46%) than in C (90%, 85%, 81%), p = 0.008. The cumulative incidence of kidney and pancreas acute rejection (AR) was higher in AA compared with C. Distribution of kidney and pancreas rejection grade was similar between C and AA. AA experienced more pancreas graft losses from early death with functioning graft, AR, and late chronic rejection. The higher incidence of AR and resistance to currently employed induction, maintenance, and antirejection immunosuppression therapies in AA may account for their inferior pancreas graft survival. More aggressive immunosuppression strategies may improve pancreas graft survival in AA but may be associated with increased morbidity and mortality. Further study is warranted.

The current disparity of viable organs and patients in need of a transplant has been an impetus for innovative measures. Live donor renal transplantation offers significant advantages compared with cadaveric donor transplantation: increased graft and patient survival, diminution in incidence of delayed graft function, acute tubular necrosis (ATN), and reduction in waiting time. Notwithstanding these gains live donors continue to be underutilized and account for only approximately one quarter of all renal transplants performed in the United States. It has been felt that inherent disincentives to live donation have slowed its growth. These include degree and duration of postoperative pain and convalescence, child care concerns, cosmetic concerns, and time until return to full activities and employment. In an attempt to curtail the disincentives to live donation, laparoscopic live donation (laparoscopic donor nephrectomy; LDN) was developed. The purpose of this study was to compare the results of our first 25 laparoscopic nephrectomies (performed over a 10-month period from September 1998 through July 1999) with the previous 25 standard open donor nephrectomies (ODNs) completed over the past 3 years. We conducted a retrospective review of all donor nephrectomies and recipient pairs performed over the past 3 years. End points included sex, operative time, length of stay, immediate and long-term renal function, and willingness to donate. There were no differences in demographics of the ODN versus the LDN group. The average length of stay was 2.48 ± 0.72 days for the LDN versus 4.08 ± 0.28 days for the ODN. ODN and LDN have comparable short- and long-term function with no delayed graft function and no complications. Growth of living donor transplant has increased from 16 per cent of all kidney transplants performed in 1995 to 23 per cent in 1999. We conclude that LDN is a viable alternative to the standard donor operation. LDN has had a positive impact on the donor pool by minimizing disincentives to live donation. With the initiation of our laparoscopic program the number of LDNs has increased. Presently the live donor pool is the most viable alternative to significantly increase the number of kidneys for transplantation.

Neoral was replaced with a generic cyclosporine formulation on our hospital formulary. We compared outcomes for de novo kidney transplant recipients who either received Gengraf (n=88) or Neoral (n=100) in a single-center, retrospective review. As compared to patients who received Neoral, patients who received Gengraf were significantly more likely to have an acute rejection episode (39% vs. 25%, P=0.04), more likely to have a second rejection episode (13% vs. 4%; P=0.03), or to have received an antibody preparation to treat acute rejection (19% vs. 8%; P=0.02). Patients treated with Gengraf had a higher degree of intrapatient variability for cyclosporine trough concentrations as determined by %CV (P

Fear of postoperative pain is a disincentive to living donor kidney transplantation. Laparoscopic donor nephrectomy (LDN) was developed in part to dispel this disincentive. The dramatic increase in the number of laparoscopic donor nephrectomies performed at our institution has been in part due to the reduction in postoperative pain as compared to traditional, open donor nephrectomy. We sought to further diminish the pain associated with this surgical technique. The purpose of this study was to compare the efficacy of three different postoperative pain management regimens after LDN. All living kidney donors performed laparoscopically (n=43) between September 1998 and April 2000 were included for analysis. Primary endpoints included postoperative narcotic requirements and length of stay. Narcotic usage was converted to morphine equivalents (ME) for comparison purposes. Patients received one of three pain control regimens (group 1: oral and intravenous narcotics; group II: oral and intravenous narcotics and the On-Q pump delivering a continuous infusion of subfascial bupivicaine 0.5%; and group III: oral and intravenous narcotics and subfascial bupivicaine 0.5% injection). Postoperative intravenous and oral narcotic use as measured in morphine equivalents was significantly less in group III versus groups I and II (group III: 28.7 ME versus group I: 40.2 ME, group II: 44.8 ME; P

Difunctional reactive polymers, telechelics, were used to reactively form multiblock copolymers in situ when melt-blended with a blend of polystyrene and polyisoprene. To quantify the ability of the copolymer to compatibilize the blends, the time evolution of the domain size upon annealing was analyzed by SEM. It was found that the most effective parameter to quantify the ability of the copolymer to inhibit droplet coalescence is K(rel)t(stable), the relative coarsening constant multiplied by the stabilization time. These results indicate that intermediate-molecular-weight telechelic pairs of both highly reactive Anhydride-PS-Anhydride/NH(2)-PI-NH(2) and slower reacting Epoxy-PS-Epoxy/COOH-PI-COOH both effectively suppress coalescence, with the optimal molecular weight being slightly above the critical molecular weight of the homopolymer, M(c). The effects of telechelic loading were also investigated, where the optimal loading concentration for this system was 0.5 wt %, as higher concentrations exhibited a plasticizing effect due to the presence of unreacted low-molecular-weight telechelics present in the blend. A determination of the interfacial coverage of the copolymer shows that a conversion of approximately 1.5-3.0% was required for 20% surface coverage at 5.0 wt % telechelic loading, indicating a large excess of telechelics in this system. At the optimal loading level of 0.5 wt %, a conversion of 15% was required for 20% surface coverage. The results of these experiments provide a clear understanding of the role of telechelic loading and molecular weight on its ability to reactively form interfacial modifiers in phase-separated polymer blends and provide guidelines for the development of similar reactive processing schemes that can use telechelic polymers to reactively compatibilize a broad range of polymer blends.

Objective The objective of this study was to review the incidence, risk factors, and impact of bacteremia after pancreas transplantation (PTX). Methods We performed a retrospective analysis of consecutive simultaneous kidney-pancreas transplantations (SKPTs) and solitary PTXs from January 2002 through April 2007. Positive blood cultures were correlated with other coexisting infections and parameters. Results One hundred ten PTXs with enteric drainage included 80 SKPTs and 30 solitary PTXs. Mean follow-up was 32 months. Bacteremia occurred in 29 (26%) patients with 5 (17%) being recurrent; it was seen during the first month after transplantation in 13 (12%), between 1 and 3 months in 12 (11%), between 3 and 12 months in 3 (3%), and after the first year in 3 cases (3%). Typical organisms were as follows: MRSE, MSSE, Klebsiella, Escherichia coli , vancomycin-resistant enterococci (VRE), and Acinetobacteri . Bacteremia was associated with coexisting site infection in 20 cases (69%): deep abdominal wound (31%); line (31%); urinary tract (34%); and pulmonary (7%). Similar bacterial species in blood and a coexisting site occurred in 15 cases (52%). No correlation was seen with cytomegalovirus (CMV) infections. In the first year, bacteremia was associated with more acute rejection episodes (32% vs 17%; P = .09), surgical complications (54% vs 42%; P = .267), mortality (11% vs 4%; P = .15), and death-censored pancreatic (14% vs 9%; P = .39) and kidney (4% vs 0; P = .08) graft loss. Fewer patients with bacteremia received alemtuzumab compared with rATG induction (14% vs 39%; P = .04). Conclusions Bacteremias were common within 3 months of PTX. A significant number (39%) were multidrug resistant. The majority were accompanied by abdominal, urinary, or line infections. Bacteremias were associated with slightly higher incidences of rejection, mortality, and graft loss.

Objective. To analyze outcomes in simultaneous kidney-pancreas transplantation (SKPT) recipients who retain C-peptide production at the time of SKPT. Methods. This retrospective analysis of SKPTs from January 2002 through January 2007 compared outcomes between patients with absent or low C-peptide levels (

Background. Despite advances in antiviral therapies, cytomegalovirus (CMV) remains the leading opportunistic infection in the transplant population. Valganciclovir (VGC), the l-valyl ester prodrug of ganciclovir (GCV), provides an excellent oral alternative to GCV for the prevention of CMV in transplant recipients. We investigated the use of VGC for CMV prevention in high-risk renal and pancreas transplant recipients. Methods. Patients at high risk for development of CMV disease were defined as either those who had donor positive, recipient-negative serostatus (D+/R−), or those who received antilymphocyte antibody (ALA) therapy for either rejection treatment or induction. A retrospective review was conducted of all kidney and pancreas transplants performed between August 2001 and December 2003. A total of 341 transplants were performed, of which 109 received VGC, and 88 were included in this analysis. Results. The overall incidence of CMV disease was 5.7% (5/88). All of the CMV episodes were in patients who were D+/R− (17.2% [5/29] versus 0% [0/59], P

Sirolimus (SRL) rescue in kidney-pancreas transplantation has not been well described. We reviewed 112 KPTxs performed at our institution between December 3, 1995 and June 27, 2002. All patients received antibody induction, tacrolimus (TAC), mycophenolate mofetil (MMF), and steroids. In 35 patients, SRL was substituted for MMF for the following reasons: acute rejection (AR) of kidney or pancreas despite adequate TAC levels, MM F intolerance, increasing creatinine levels, and TAC-induced hyperglycemia. Three-year kidney and pancreas graft survivals were 97% and 90%, respectively. Of 10 patients who were switched to SRL because of AR, one kidney failed because of antibody-resistant AR, and one kidney developed borderline AR; the other eight patients remain AR-free. AR developed in seven other patients despite therapeutic SRL levels; six had TAC levels less than 4.5 ng/mL. The mean creatinine levels overall and for the group with increasing creatinine remained stable. All patients who were switched to SRL for TAC-induced hyperglycemia or MMF intolerance improved. Kidney-pancreas transplant recipients can be safely switched to SRL with excellent graft and patient survival.

The aim of this study was to evaluate long-term outcome of sirolimus (SRL) rescue in kidney-pancreas transplantation (KPTx). We reviewed 112 KPTx performed at our institution from 12/3/95 to 6/27/02. All patients received antibody (Ab) induction, tacrolimus (TAC), mycophenolate mofetil (MMF), and steroids. Thirty-five patients (31%) had SRL substituted for MMF for the following indications: (1) acute rejection (AR) of kidney or pancreas despite adequate TAC levels; (2) intolerance of full-dose MMF; (3) rising creatinine; and (4) TAC-induced hyperglycemia. Target SRL and TAC levels were 10 ng/mL and 5 ng/mL, respectively. Mean follow-up was 3 +/- 2 years overall and 1.2 +/- 0.5 years after SRL rescue. No patients died. One- and 3-year actuarial kidney and pancreas graft survival was 97%, 97%, and 95%, 90%, respectively. Of 10 patients switched to SRL for AR, 1 kidney failed from Ab-resistant AR, 1 kidney developed borderline AR, and the other 8 remain AR-free. Seven other patients developed AR despite therapeutic SRL levels; of these, 6 (86%) had mean TAC levels of4.5 in the month preceding AR. Mean creatinine overall and for the rising creatinine group remained stable. All patients switched to SRL for TAC-induced hyperglycemia or MMF intolerance demonstrated biochemical or clinical improvement. Sirolimus-related infection or other serious adverse events (SAE) were uncommon. In conclusion, KPTx recipients can be safely switched to SRL with long-term stabilization of renal function, excellent graft and patient survival, and no increase in SAE. A minimum TAC level of 4.5 ng/mL may be necessary to prevent late AR.

The influence of body mass index (BMI) on outcome of simultaneous pancreas-kidney transplantation (SPK) has not been well described. We retrospectively reviewed 88 consecutive primary SPKs performed at our institution between March 15, 1995 and August 28, 2001. All patients received antibody induction and maintenance immunosuppression with tacrolimus, mycophenolate mofetil, and steroids. Systemicenteric implantation was performed in all patients. Primary end points were patient, pancreas, and kidney survival. Secondary end points were rates of anastomotic leakage, pancreas thrombosis, major infection, rejection, repeat laparotomy, and length of hospital stay. Values are shown as mean ± standard deviation, range, or percentage. Fifty-two patients (59.1%) were nonobese with a BMI ≦24.9 (mean 21.7 ± 2.2, range 15.4 to 24.9). Thirty-six patients were mild to moderately obese with a BMI ≧25 (mean 27.7 ± 2.2, range 25 to 35.1). Distribution of recipient age, sex, and ethnicity was similar between groups. Kidney and pancreas preservation times were similar between nonobese and obese patients. One-, three-, and five-year actuarial patient (nonobese: 95%, 95%, 95% vs. obese: 95%, 95%, 89%), kidney graft (nonobese: 91%, 91%, 87% vs. obese: 97%, 91%, 85%), and pancreas graft (nonobese: 78%, 78%, 73% vs. obese: 70%, 62%, 62%) survival were comparable between nonobese and obese (P = NS). The mean rates of pancreas thrombosis, major infection, pancreas rejection, kidney rejection, relaparotomy, and length of hospital stay were similar in the two groups. The overall duodenojejunal anastomotic leakage rate was 8%. Obese patients had a 17% incidence of leakage (6 of 36) compared to a 2% incidence of leakage in nonobese patients (P = 0.012). Six of seven leaks occurred in obese patients. Mean BMI in the seven patients with a leak (27 ± 1.9) was significantly higher than in patients who did not develop a leak (24 ± 3.7; P = 0.05). Although obesity had no effect on patient or graft survival, it was associated with a significantly higher leakage rate. There should therefore be a higher degree of suspicion for the presence of duodenojejunal anastomotic leaks in obese SPK recipients.

Fear of postoperative pain is a disincentive to living donor kidney transplantation. Laparoscopic donor nephrectomy (LDN) was developed in part to dispel this disincentive. The dramatic increase in the number of laparoscopic donor nephrectomies performed at our institution has been in part due to the reduction in postoperative pain as compared to traditional, open donor nephrectomy. We sought to further diminish the pain associated with this surgical technique. The purpose of this study was to compare the efficacy of three different postoperative pain management regimens after LDN. All living kidney donors performed laparoscopically (n=43) between September 1998 and April 2000 were included for analysis. Primary endpoints included postoperative narcotic requirements and length of stay. Narcotic usage was converted to morphine equivalents (ME) for comparison purposes. Patients received one of three pain control regimens (group 1: oral and intravenous narcotics; group II: oral and intravenous narcotics and the On-Q pump delivering a continuous infusion of subfascial bupivicaine 0.5%; and group III: oral and intravenous narcotics and subfascial bupivicaine 0.5% injection). Postoperative intravenous and oral narcotic use as measured in morphine equivalents was significantly less in group III versus groups I and II (group III: 28.7 ME versus group I: 40.2 ME, group II: 44.8 ME; P0.05). Postoperative length of stay was also shorter for group III (1.8 days) versus group I (2.5 days) and group II (2.9 days). LDN has been shown to be a viable alternative to traditional open donor nephrectomy for living kidney donation. We observed that the use of combined oral and intravenous narcotics alone is associated with greater postoperative narcotic use and increased length of stay compared to either a combined oral and intravenous narcotics plus continuous or single injection subfascial administration of bupivicaine. The progressive modification of our analgesic regimen has resulted in decreased postoperative oral and intravenous narcotic use and a reduction in the length of stay. We recommend subfascial infiltration with bupivicaine to the three laparoscopic sites and the pfannenstiel incision at the conclusion of the procedure to reduce postoperative pain. We believe this improvement in postoperative pain management will continue to make LDN even more appealing to the potential living kidney donor.

Desmopressin (DDAVP) is commonly used in cadaveric organ donors to treat diabetes insipidus. The thrombogenic potential of DDAVP is well known. Recent animal data have demonstrated that DDAVP impairs pancreas graft (PG) microcirculation and perfusion. The aim of this study was too evaluate the effect of DDAVP on the incidence of PG thrombosis in clinical pancreas transplantation. A retrospective review of simultaneous kidney–pancreas transplant (SKPT) entered in the Scientific Registry of Transplant Recipients (SRTR) between 10/5/87 and 9/27/02 was performed. Patients were included for analysis if there was definitive documentation as to whether DDAVP was (DDAVP-Y) or was not (DDAVP-N) administered to the donor. Both dose and duration of DDAVP treatment were not recorded by SRTR. A total of 2804 SKPTs were available for analysis. Mean follow-up was 1.75 years (range, 1 month to 8.4 years). A total of 1287 SKPT patients (46%) received a PG from a DDAVP-Y donor. Graft ischemia times, donor and recipient ages, recipient gender distribution, surgical techniques, and immunosuppressive regimens were similar in both groups. The overall incidence of PG thrombosis was 4.3%. The incidence of PG thrombosis in recipients of grafts from DDAVP-Y donors was 5.1% compared to 3.5% in recipients of grafts from DDAVP-N donors ( P = .04). Fifty-eight percent of thrombosed PG came from DDAVP-Y donors compared to 42% from DDAVP-N donors ( P = .04). We conclude that there appears to be a relationship between donor treatment with DDAVP and PG thrombosis. A prospective study is needed to verify these findings and to determine their clinical significance.

The purpose of this study was to examine neuropsychological profiles for patients with spina bifida. The sample consisted of 37 subjects with spina bifida between the ages of 14 and 23. Each of the subjects was seen individually and administered the Halstead-Reitan Neuropsychological Test Battery as well as the appropriate Wechsler Intelligence Scale. Scores from the Halstead-Reitan were subjected to cluster analysis to formulate clinical subtypes. The results indicated a three group solution was most appropriate, which appeared to reflect a continuum of dysfunction. Implications for rehabilitation programming are discussed.

The selective toxicity of purine deoxyribonucleosides for T-lymphoblasts appears to be mediated by the selective accumulation of the corresponding deoxyribonucleoside triphosphates in these cells. This finding has led to a search for deoxyribonucleoside analogues which may have clinical utility in T-cell lymphoproliferative disorders. 9-beta-D-arabinofuranosylguanine (ara-G) is a 2'-deoxyguanosine analogue which is 70-fold more inhibitory to the growth of T- than of B-lymphoblasts. It is less potent than ara-C but far more selective in its cytotoxic effect on T-cells. ara-G is not significantly degraded by purine nucleoside phosphorylase (EC 2.4.2.1) activity in T-lymphoblasts and is metabolized to 9-beta-D-arabinofuranosylguanine 5'-triphosphate. The accumulation of this metabolite directly correlates with inhibition of DNA but not of RNA or protein synthesis. MOLT-4 T-lymphoblasts were selected for ara-G resistance, and six clones were identified which exhibited a major degree of resistance to 2'-deoxyguanosine but little or none to ara-C. Further characterization of clone 24B3 revealed a 600-fold increase in ara-G resistance, a 36-fold increase in 2'-deoxyguanosine resistance, and only a 4-fold increase in 1-beta-D-arabinofuranosylcytosine resistance. The 24B3 cell line accumulated less than 10% of 9-beta-D-arabinofuranosylguanine 5'-triphosphate and 2'-deoxyguanosine 5'-triphosphate from the corresponding nucleosides as compared to wild-type MOLT-4 cells; in contrast, 1-beta-D-arabinofuranosylcytosine 5'-triphosphate accumulation was approximately 30% of control values. Thus, ara-G differs from 1-beta-D-arabinofuranosylcytosine in its selectivity for cultured T-lymphoblasts and may be of use as a chemotherapeutic or immunosuppressive agent.

Forty-two severely retarded patients, ranging in age from 2 to 26 years, were referred for diagnostic evaluation because of chronic vomiting. The diagnosis of gastroesophageal reflux (GER) was made in 28 of the basis of reflux (grade III) on upper gastrointestinal series and the presence of esophagitis either grossly at endoscopy or on esophageal biopsy. Nissen fundoplication was performed in 22 because of the frequent occurrence of complications such as pneumonia, gastrointestinal blood loss, and malnutrition attributable to GER. The incidence of postoperative complications was 59%. However, during a mean follow-up period of 14.1 months, no further vomiting or gastrointestinal blood loss was encountered, and only one patient had a single episode of pneumonia. Weight gain in those who were malnourished was impressive. In addition, the already difficult care of the patients was greatly facilitated. Severely retarded patients with GER who suffer recurrent complications should be considered for Nissen fundoplication.

This paper describes the techniques used in writing a low level program using a high level programming language. The program that was written is a driver for use with terminal type devices interfaced to the HP 12966A interface card. This driver operates in the RTE-IVB operating system on a Hewlett-Packard HP1000 mini computer. Included is a discussion of the advantages and disadvantages of doing systems programming in a high level language, as well as the working code for the driver written in C.