Traumatic grief as a risk factor for mental and physical morbidity

OBJECTIVE

The aim of this study was to confirm and extend the authors' previous work indicating that symptoms of traumatic grief are predictors of future physical and mental health outcomes.

METHOD

The study group consisted of 150 future widows and widowers interviewed at the time of their spouse's hospital admission and at 6-week and 6-, 13-, and 25- month follow-ups. Traumatic grief was measured with a modified version of the Grief Measurement Scale. Mental and physical health outcomes were assessed by self-report and interviewer evaluation. Survival analysis and linear and logistic regressions were used to determine the risk for adverse mental and physical health outcomes posed by traumatic grief.

RESULTS

Survival and regression analyses indicated that the presence of traumatic grief symptoms approximately 6 months after the death of the spouse predicted such negative health outcomes as cancer, heart trouble, high blood pressure, suicidal ideation, and changes in eating habits at 13- or 25-month follow-up.

CONCLUSIONS

The results suggest that it may not be the stress of bereavement, per se, that puts individuals at risk for long-term mental and physical health impairments and adverse health behaviors. Rather, it appears that psychiatric sequelae such as traumatic grief are of critical importance in determining which bereaved individuals will be at risk for long-term dysfunction.

Comparison of open and laparoscopic live donor nephrectomy

OBJECTIVE

This study compares an initial group of patients undergoing laparoscopic live donor nephrectomy to a group of patients undergoing open donor nephrectomy to assess the efficacy, morbidity, and patient recovery after the laparoscopic technique.

SUMMARY BACKGROUND DATA

Recent data have shown the technical feasibility of harvesting live renal allografts using a laparoscopic approach. However, comparison of donor recovery, morbidity, and short-term graft function to open donor nephrectomy has not been performed previously.

METHODS

An initial series of patients undergoing laparoscopic live donor nephrectomy were compared to historic control subjects undergoing open donor nephrectomy. The groups were matched for age, gender, race, and comorbidity. Graft function, intraoperative variables, and clinical outcome of the two groups were compared.

RESULTS

Laparoscopic donor nephrectomy was attempted in 70 patients and completed successfully in 94% of cases. Graft survival was 97% versus 98% (p = 0.6191), and immediate graft function occurred in 97% versus 100% in the laparoscopic and open groups, respectively (p = 0.4961). Blood loss, length of stay, parenteral narcotic requirements, resumption of diet, and return to normal activity were significantly less in the laparoscopic group. Mean warm ischemia time was 3 minutes after laparoscopic harvest. Morbidity was 14% in the laparoscopic group and 35% in the open group. There was no mortality in either group.

CONCLUSIONS

Laparoscopic live donor nephrectomy can be performed with morbidity and mortality comparable to open donor nephrectomy, with substantial improvements in patient recovery after the laparoscopic approach. Initial graft survival and function rates are equal to those of open donor nephrectomy, but longer follow-up is necessary to confirm these observations.

Pegylated interferon-alpha2b: pharmacokinetics, pharmacodynamics, safety, and preliminary efficacy data. Hepatitis C Intervention Therapy Group

AIMS

The objectives of this study were to assess the safety, pharmacokinetic and pharmacodynamic profiles, and antiviral efficacy of pegylated interferon-alpha2b monotherapy in patients with chronic hepatitis C.

METHODS

Fifty-eight patients (38 men, 20 women; age range, 25 to 65 years) with compensated chronic hepatitis C were enrolled in this open-label, randomized, active controlled study. Patients received 0.035 to 2.0 microg/kg pegylated interferon-alpha2b subcutaneously weekly or the active control, interferon-alpha2b 3 million IU subcutaneously three times/week, for 24 weeks. Safety and antiviral efficacy assessments were performed during treatment and in a subsequent 4-week follow-up period. Detailed pharmacokinetic assessments were performed at weeks 1 and 4.

RESULTS

Pegylated interferon-alpha2b produced dose-related reductions in white blood cells, neutrophils, and platelets, and dose-related increases in oral temperature, serum neopterin, and serum 2'5'-oligoadenylate synthetase activity, which were qualitatively similar to those produced by nonpegylated interferon-alpha2b. Reported adverse events (flu-like symptoms, asthenia) were qualitatively similar in pegylated interferon-alpha2b- and nonpegylated interferon-alpha2b-treated groups. Dose-related antiviral activity, as measured by loss of detectable serum hepatitis C virus RNA (<100 copies/mL), was noted at the end of treatment and after 4 weeks of follow-up. Both pegylated and nonpegylated interferon-alpha2b were rapidly absorbed, with maximal concentrations occurring approximately 8 to 12 hours after dose administration. Pegylated interferon-alpha2b had sustained maximal serum concentrations for 48 to 72 hours after dose administration, whereas nonpegylated interferon-alpha2b concentrations declined rapidly. Volume of distribution for both compounds was similar (approximately 1 L/kg). Pegylated interferon-alpha2b elimination half-life was approximately 10-fold greater, and mean apparent clearance was one tenth that of nonpegylated interferon-alpha2b.

CONCLUSIONS

Pegylated and nonpegylated interferon-alpha2b safety and pharmacodynamic profiles were comparable. Pegylated interferon-alpha2b demonstrated delayed clearance compared with nonpegylated interferon-alpha2b, consistent with once-weekly administration.

Blockade of the type I somatomedin receptor inhibits growth of human breast cancer cells in athymic mice

Insulin and insulin-like growth factors (IGIs) stimulate the growth of human breast cancer cells in vitro. The type I somatomedin receptor (SR) expressed in these cells may mediate the growth effects of these peptides. We have examined the role of this receptor on human breast cancer growth with a monoclonal antibody (alpha-IR-3) that blocks the receptor binding domain and inhibits IGF-I-induced growth. alpha-IR-3 inhibited clonal growth in vitro and blocked the mitogenic effect of exogenous IGF-I in both MCF-7 and MDA-231 breast cancer cell lines. Antibody-induced blockade of the type I SR also inhibited the estrogen-independent MDA-231 cells growing in vivo in nude mice, but growth of the estrogen-dependent MCF-7 cells was unaffected. IGIs are important growth regulators of MDA-231 breast cancer cells. Blockade of this growth stimulatory pathway may provide a new treatment strategy.

Complicated grief as a disorder distinct from bereavement-related depression and anxiety: a replication study

OBJECTIVE

This study sought to confirm in an independent, nonclinical study group previous work which demonstrated that the symptoms of complicated grief were distinct from the symptoms of bereavement related depression and anxiety.

METHOD

Data used in the analyses were derived from a group of 150 widowed individuals who were interviewed 6 months after their deceased spouses' hospital admission (study entry). Complicated grief was measured with a modified version of the Grief Measurement Scale. Principal axis factoring was used to determine the distinctiveness of complicated grief, depression, and anxiety.

RESULTS

The principal axis factoring showed that the symptoms of complicated grief loaded quite highly on the first (complicated grief) factor and loaded very poorly on the anxiety and depression factors.

CONCLUSIONS

The results confirmed the authors' previous findings demonstrating the distinction between symptoms of complicated grief and symptoms of bereavement-related depression and anxiety.

Increased rates of donation with laparoscopic donor nephrectomy

OBJECTIVE

To examine the impact of laparoscopic nephrectomy and recipient education on the proportion of kidney recipients who could identify a potential live donor, and on the live donor (LD) transplantation rate.

SUMMARY BACKGROUND DATA

Laparoscopic donor nephrectomy (LDN) results in less postoperative surgical pain, a shorter hospital stay, and quicker recovery than the standard open donor nephrectomy (ODN). The authors hypothesized that the availability of this less invasive surgical technique would enhance the willingness of family and friends to donate.

METHODS

The study population consisted of 3,298 end-stage renal disease patients referred for kidney transplant evaluation between November 1991 and February 2000, divided into three groups. The first group received no formal LD education and had only ODN available. The second group received formal education about the LD process and had only ODN available. The third group had both formal LD education and LDN available. Records were examined to determine what proportion of each group had any potential donors tissue-typed, and the rate at which they received an LD transplant.

RESULTS

Before LDN availability and formal LD education, only 35.1% of referrals found a potential donor, and only 12.2% received an LD transplant within 3 years. Institution of a formal education program increased the volunteer rate to 39.0%, and 16.5% received an LD transplant. When LDN became available, 50% of patients were able to find at least one potential donor, and within 3 years 24.7% received an LD transplant. Regression analysis indicated that availability of LDN was independently associated with a 1.9 relative risk of receiving an LD transplant. Kaplan-Meier death-censored 1- and 3-year graft survival rates for ODN transplants were 95.8% and 90.6%, versus 97.5% and 94. 8% for LDN.

CONCLUSIONS

The availability of LDN and an LD family education program has doubled the live donor transplantation rate, and outcomes remain excellent.

Phorbol esters stimulate the phosphorylation of receptors for insulin and somatomedin C

The effect of phorbol esters on the extent of phosphorylation of receptors for insulin and somatomedin C (insulin-like growth factor I) was studied in intact IM-9 cells that were labeled by incubation with H332PO4. The tumor-promoting phorbol esters phorbol tetradecanoate acetate (TPA) and phorbol dibutyrate, but not the inactive 4 alpha-phorbol, enhanced phosphorylation of the beta subunit of both receptors approximately 4-fold; 70 nM TPA maximally stimulated phosphorylation of both receptors, whereas concentrations less than or equal to 0.7 nM had no observable effect. Insulin also enhanced the phosphorylation of the beta subunit of the insulin receptor, and its effects appeared to be additive to those of TPA. Peptide maps indicated that at least some of the residues phosphorylated by these two agents are distinct. These results suggest a possible role of protein kinase C in regulating insulin and somatomedin C receptors.

The function of the soluble interleukin 6 (IL-6) receptor in vivo: sensitization of human soluble IL-6 receptor transgenic mice towards IL-6 and prolongation of the plasma half-life of IL-6

Interleukin 6 (IL-6) is considered an important mediator of acute inflammatory responses. Moreover, IL-6 functions as a differentiation and growth factor of hematopoietic precursor cells, B cells, T cells, keratinocytes, neuronal cells, osteoclasts, and endothelial cells. IL-6 exhibits its action via a receptor complex consisting of a specific IL-6 receptor (IL-6R) and a signal transducing subunit (gp130). Soluble forms of both receptor components are generated by shedding and are found in patients with various diseases such as acquired immune deficiency syndrome, rheumatoid arthritis, and others. The function of the soluble (s)IL-6R in vivo is unknown. Since human (h)IL-6 acts on human and murine target cells, but murine IL-6 on murine cells only, we constructed transgenic mice expressing the hsIL-6R. We report here that in the presence of hsIL-6R, mice are hypersensitized towards hIL-6, mounting an acute phase protein gene induction at significantly lower IL-6 dosages compared to control animals. Furthermore, in hsIL-6R transgenic mice, the detected acute phase response persists for a longer period of time. The IL-6/IL-6R complex prolongs markedly the Il-6 plasma half-life. Our results reinforce the role of the hsIL-6R as an agonistic protein, help to understand the function of the hsIL-6R in vivo, and highlight the significance of the receptor in the induction of the acute phase response.

Computer-enhanced "robotic" cardiac surgery: experience in 148 patients

OBJECTIVE

A computer-enhanced instrumentation system was used in 148 patients to minimize access in cardiac surgical procedures.

METHODS

The da Vinci telemanipulation system (Intuitive Surgical, Mountain View, Calif) provides a high-resolution 3-dimensional videoscopic image and allows remote, tremor-free, and scaled control of endoscopic surgical instruments with 6 degrees of freedom. By April 2000, the system had been used in 131 patients for coronary artery bypass grafting and 17 patients for mitral valve repair. In the coronary bypass group, the system was used in one of three ways: (1) to take down the internal thoracic artery followed by a minimally invasive direct coronary bypass procedure (n = 81); (2) to perform the anastomosis between the internal thoracic artery and the left anterior descending coronary artery in standard-sternotomy coronary bypass (n = 15); or (3) for total endoscopic coronary artery bypass grafting to anastomose the left internal thoracic artery to the left anterior descending on the arrested heart (n = 27) or the beating heart (n = 8). In 17 patients with nonischemic mitral valve insufficiency the mitral valve was repaired. Closed-chest cardiopulmonary bypass with cardioplegic arrest (Port-Access technique; Heartport, Inc, Redwood City, Calif) was used for arrested-heart total endoscopic coronary bypass and mitral valve repair.

RESULTS

The da Vinci system allows for precise tissue handling and enables the endoscopic performance of cardiac surgical tasks that require a high degree of dexterity (coronary anastomosis, mitral valve repair). No technical mishaps have occurred. The internal thoracic artery was successfully taken down in 79 of 81 patients in the group undergoing minimally invasive coronary bypass and, after a steep learning curve, is currently performed in less than 40 minutes. The postoperative patency rate is 96.3%. Total endoscopic coronary bypass was completed in 22 of 27 cases with 95.4% patency as demonstrated by angiography at 3 months' follow-up. Closed-chest endoscopic beating-heart bypass grafting was successfully performed in 2 out of 8 patients with the use of a new endoscopic stabilizer. In the group having mitral valve repair, primary endoscopic computer-enhanced repair was successfully completed in 14 of 17 patients; three others had to be changed to a standard endoscopic technique, including 1 who required valve replacement. At 3 months' follow-up, 1 additional patient underwent early reoperation for recurrent mitral insufficiency. Overall early and late mortality in this cohort of 148 patients was 2.0% and was not related to the use of the system.

CONCLUSION

In conclusion, computer-enhanced endoscopic cardiac surgery can be performed safely in selected patients. Internal thoracic artery takedown is now routinely performed with good results. Total endoscopic coronary bypass is feasible on the arrested heart but does not offer a major benefit over the minimally invasive direct approach because cardiopulmonary bypass is still required. The early clinical experience with closed-chest beating-heart bypass grafting outlines the limitations of this approach despite some procedural success.

The mobile receptor hypothesis and "cooperativity" of hormone binding. Application to insulin

The mobile receptor hypothesis has been proposed to describe the process by which hormone receptor binding initiates a biological response; it states that receptors, which can diffuse independently in the plane of the membrane, reversibly associate with effectors to regulate their activity. The affinity for effector is greater when the receptor is occupied by hormone. A mathematical expression of the mobile receptor hypothesis is used to show that: (1) The predicted kinetics of hormone receptor binding may be indistinguishable from "negative cooperativity." (2) Receptor occupancy and biological response may be coupled in a non-linear fashion. By choosing specific parameters, most of the existing data on insulin binding and biological responses can be explained in terms of the mobile receptor hypothesis. Thus, the following are easily explained: (1) A single homogeneous receptor may appear kinetically to be composed of two classes (of high and low affinity) of receptors. (2) Occupancy of the apparent class of high affinity receptors is related linearly to the biological response. (3) The same receptor in different tissues may appear to have different affinity. (4) The binding of different biologically active insulin analogues may exhibit different degrees of "cooperativity." These considerations may also be pertinent to interpretations of other hormone-receptor systems and of various ligand-macromolecule interactions.

G-CSF-mobilized peripheral blood progenitor cells for allogeneic transplantation: safety, kinetics of mobilization, and composition of the graft

Allogeneic transplantation of peripheral blood progenitor cells (PBPC) makes the general anaesthesia of the donor unnecessary and may result in more rapid engraftment and faster recovery of the immune system. We have studied G-CSF-mediated PBPC mobilization in healthy donors and analysed the cellular composition of the resulting PBPC grafts. PBPC grafts were obtained from nine healthy donors (18-67 years old) for allogeneic or syngeneic transplantation. Six donors received 10 micrograms/kg G-CSF per day, the others 5-6 micrograms/kg. Mobilization and harvesting were well tolerated except for moderate bone pain which occurred in all donors primed with 10 micrograms/kg. With 10 micrograms/kg, a 31-fold (9-62) enrichment of circulating CD34+ cells was observed with peak values constantly occurring on day 5 after the start of G-CSF administration. Starting harvest on day 5, one to three collections on consecutive days yielded 5.5 x 10(6)/kg (0.9-10.7) CD34+ cells, 219 x 10(6)/kg (106-314) T cells, and 34 x 10(6)/kg (23-67) NK cells per 10 litres leukapheresis volume. Altogether, PBPC grafts contained 3 times more CD34+ cells, 7 times more T cells, and 20 times more NK cells than five allogeneic marrow grafts that were analysed for comparison. The yield of CD34+ cells per 10 litres apheresis volume as well as the height of the CD34+ peak in peripheral blood were inversely correlated to the age of the donor. In the donors primed with 5-6 micrograms/kg G-CSF the increase of circulating CD34+ cells (4-7-fold enrichment) and the CD34+ cell yield per 10 litres leukapheresis volume (1 x 10(6)/kg [0.8-2.2]) was much smaller compared with the 10 micrograms/kg group. In conclusion, sufficient amounts of PBPC capable of restoring haemopoiesis in allogeneic recipients can be mobilized safely by administration of G-CSF (10 micrograms/kg s.c. for 5 d) in healthy donors, and harvested with one or two leukapheresis procedures. Whether the large numbers of T-cells and NK cells that are contained in the collection products may influence graft-versus-host and graft-versus-leukaemia reactivities of PBPC grafts remains to be determined.

Genomic organization and partial duplication of the human alpha7 neuronal nicotinic acetylcholine receptor gene (CHRNA7)

The human alpha7 neuronal nicotinic acetylcholine receptor gene (HGMW-approved symbol CHRNA7) has been characterized from genomic clones. The gene is similar in structure to the chick alpha7 gene with 10 exons and conserved splice junction positions. The size of the human gene is estimated to be larger than 75 kb. A putative promoter 5' of the translation start in exon 1 has been cloned and sequenced. The promoter region lacks a TATA box and has a high GC content (77%). Consensus Sp1, AP-2, Egr-1, and CREB transcription factor binding sites appear to be conserved between bovine and human genes. The alpha7 nAChR gene was found to be partially duplicated, with both loci mapping to the chromosome 15q13 region. A yeast artificial chromosome contig was constructed over a genetic distance of 5 cM that includes both alpha7 loci and the region between them. Four novel exons are described, located in genomic clones containing the partially duplicated gene. The duplicated sequences, including the novel exons, are expressed in human brain.

Vitamin A deprivation results in reversible loss of hippocampal long-term synaptic plasticity

Despite its long history, the central effects of progressive depletion of vitamin A in adult mice has not been previously described. An examination of vitamin-deprived animals revealed a progressive and ultimately profound impairment of hippocampal CA1 long-term potentiation and a virtual abolishment of long-term depression. Importantly, these losses are fully reversible by dietary vitamin A replenishment in vivo or direct application of all trans-retinoic acid to acute hippocampal slices. We find retinoid responsive transgenes to be highly active in the hippocampus, and by using dissected explants, we show the hippocampus to be a site of robust synthesis of bioactive retinoids. In aggregate, these results demonstrate that vitamin A and its active derivatives function as essential competence factors for long-term synaptic plasticity within the adult brain, and suggest that key genes required for long-term potentiation and long-term depression are retinoid dependent. These data suggest a major mental consequence for the hundreds of millions of adults and children who are vitamin A deficient.

Cooling for newborns with hypoxic ischaemic encephalopathy

BACKGROUND

Newborn animal studies and pilot studies in humans suggest that mild hypothermia following peripartum hypoxia-ischaemia in newborn infants may reduce neurological sequelae without adverse effects.

OBJECTIVES

To determine the effect of therapeutic hypothermia in encephalopathic asphyxiated newborn infants on mortality, long-term neurodevelopmental disability and clinically important side effects.

SEARCH STRATEGY

The standard search strategy of the Neonatal Review Group as outlined in The Cochrane Library (Issue 2, 2007) was used. Randomised controlled trials evaluating therapeutic hypothermia in term newborns with hypoxic ischaemic encephalopathy were identified by searching the Oxford Database of Perinatal Trials, the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 2, 2007), MEDLINE (1966 to June 2007), previous reviews including cross-references, abstracts, conferences, symposia proceedings, expert informants and journal hand searching.

SELECTION CRITERIA

Randomised controlled trials comparing the use of therapeutic hypothermia with standard care in encephalopathic newborn infants with evidence of peripartum asphyxia and without recognisable major congenital anomalies were included. The primary outcome measure was death or long-term major neurodevelopmental disability. Other outcomes included adverse effects of cooling and 'early' indicators of neurodevelopmental outcome.

DATA COLLECTION AND ANALYSIS

Three review authors independently selected, assessed the quality of and extracted data from the included studies. Authors were contacted for further information. Meta-analyses were performed using relative risk and risk difference for dichotomous data, and weighted mean difference for continuous data with 95% confidence intervals.

MAIN RESULTS

Eight randomised controlled trials were included in this review, comprising 638 term infants with moderate/ severe encephalopathy and evidence of intrapartum asphyxia. Therapeutic hypothermia resulted in a statistically significant and clinically important reduction in the combined outcome of mortality or major neurodevelopmental disability to 18 months of age [typical RR 0.76 (95% CI 0.65, 0.89), typical RD -0.15 (95% CI -0.24, -0.07), NNT 7 (95% CI 4, 14)]. Cooling also resulted in statistically significant reductions in mortality [typical RR 0.74 (95% CI 0.58, 0.94), typical RD -0.09 (95% CI -0.16, -0.02), NNT 11 (95% CI 6, 50)] and in neurodevelopmental disability in survivors [typical RR 0.68 (95% CI 0.51, 0.92), typical RD -0.13 (95% CI -0.23, -0.03), NNT 8 (95% CI 4, 33)]. Some adverse effects of hypothermia included an increase in the need for inotrope support of borderline significance and a significant increase in thrombocytopaenia.

AUTHORS' CONCLUSIONS

There is evidence from the eight randomised controlled trials included in this systematic review (n = 638) that therapeutic hypothermia is beneficial to term newborns with hypoxic ischaemic encephalopathy. Cooling reduces mortality without increasing major disability in survivors. The benefits of cooling on survival and neurodevelopment outweigh the short-term adverse effects. However, this review comprises an analysis based on less than half of all infants currently known to be randomised into eligible trials of cooling. Incorporation of data from ongoing and completed randomised trials (n = 829) will be important to clarify the effectiveness of cooling and to provide more information on the safety of therapeutic hypothermia, but could also alter these conclusions. Further trials to determine the appropriate method of providing therapeutic hypothermia, including comparison of whole body with selective head cooling with mild systemic hypothermia, are required.

Association of phorbol ester-induced hyperphosphorylation and reversible regulation of transferrin membrane receptors in HL60 cells

Phorbol diesters are tumor-promoting agents that cause differentiation of HL60 human leukemic cells and concomitantly alter surface transferrin-receptor expression [Rovera, G., Ferreo, D., Pagliardi, G. L., Vartikar, J., Pessano, S., Bottero, L., Abraham, S. & Lebman, D. (1982) Ann. N.Y. Acad. Sci. 397, 211-220]. Transferrin-receptor regulation is shown here to result from a rapid and reversible internalization process that is temporally associated with reversible increased phosphorylation (hyperphosphorylation) of the transferrin receptor. Such a reversible mechanism involving regulation of these surface proteins could result in the rapid generation of an early signal for HL60 cellular differentiation.

A comparison of recipient renal outcomes with laparoscopic versus open live donor nephrectomy

BACKGROUND

Laparoscopic donor nephrectomy (laparoNx) has the potential to increase living kidney donation rates by reducing the pain and suffering of the donor. However, renal function outcomes of a large series of recipients of laparoNx have not been studied.

METHODS

We retrospectively reviewed the records of 132 recipients of laparoNx done at our center between 3/96 and 11/97 and compared them to 99 recipients of kidneys procured by the open technique (openNx) done between 10/93 and 3/96.

RESULTS

Significantly more patients in the laparoNx group (25.2%) were taking tacrolimus within the first month than those in the openNx group (2.1%). Mean serum creatinine was higher in laparoNx compared with openNx at 1 week (2.8+/-0.3 and 1.8+/-0.2 mg/dl, respectively; P=0.005) and at 1 month (2.0+/-0.1 and 1.6+/-0.1 mg/dl, P=0.05) after transplant. However, by 3 and 6 months, the mean serum creatinine was similar in the two groups (1.7+/-0.1 versus 1.5+/-0.05 mg/dl, and 1.7+/-0.1 versus 1.7+/-0.1, respectively). By 1 year posttransplant, the mean serum creatinine for laparoNx was actually less than that for openNx (1.4+/-0.1 and 1.7+/-0.1 mg/dl, P=0.03). Although patients in the laparoNx compared to the openNx group were more likely to have delayed graft function (7.6 versus 2.0%) and ureteral complications (4.5 versus 1.0%), the rate of other complications, as well as hospital length of stay, patient and graft survival rates were similar in the two groups.

CONCLUSION

Although laparoNx allografts have slower initial function compared with openNx, there was no significant difference in longer term renal function.

A dose-ranging study of pegylated interferon alfa-2b and ribavirin in chronic hepatitis C. The Hepatitis C Intervention Therapy Group

The objectives of this study were to assess the safety, pharmacokinetics, and efficacy of pegylated interferon alfa-2b (PEG-Intron) plus ribavirin in patients with chronic hepatitis C. A total of 72 patients (35 men/37 women, age range 20-68 years) with clinically compensated chronic hepatitis C virus (HCV) were enrolled into this open-label, randomized, active controlled study. Patients received either PEG-Intron 0.35, 0.7, or 1.4 microg/kg subcutaneously weekly for 24 weeks alone, or in combination with ribavirin 600, 800, or 1,000 to 1,200 mg orally daily. Patients were evaluated during treatment and after a 24-week follow-up period for safety and efficacy. Detailed pharmacokinetic assessments were performed at weeks 1 and 4. PEG-Intron alone produced expected dose-related reductions in white cells, neutrophils and platelets. Addition of ribavirin reduced hemoglobin levels in a dose-related manner, did not further reduce PEG-Intron-induced decreases in neutrophil or white cell count, and increased platelet counts. Neutrophil function tests (C5a and FMLP migration, killing curves) were unaltered. Reported adverse events (flu-like symptoms, asthenia) were qualitatively similar in all dose groups. Anti-HCV activity, as measured by loss of detectable serum HCV RNA (i.e. <100 copies/mL) at the end of treatment (week 24) and after 24 weeks of follow-up (week 48) showed dose-response trends for PEG-Intron. At each PEG-Intron dose level, anti-HCV activity was higher in patients coadministered ribavirin than in patients treated with PEG-Intron monotherapy. There was no evidence of pharmacokinetic interactions with either drug. We conclude that the safety and tolerability of combined PEG-Intron/ribavirin and PEG-Intron alone were comparable. Combined PEG-Intron/ribavirin showed dose-related synergistic anti-HCV effects, which were numerically superior to those obtained with PEG-Intron monotherapy.

Antibodies to purified insulin receptor have insulin-like activity

Antibodies to insulin receptors purified from rat liver membranes do not complete with [125I]insulin for binding to the insulin receptor but do precipitate solubilized receptors labeled with [125I]insulin. These antibodies have the insulin-like activities of enhancing glucose oxidation and inhibiting epinephrine-induced lipolysis in rat adipocytes. Thus, antibody binds to the receptor at a different site from that to which insulin binds, yet the interaction can initiate an effective biological response. These results indicate that the previously studied insulin-binding sites are the physiological macromolecular receptors for insulin.

Quantitative aspects of hormone-receptor interactions of high affinity. Effect of receptor concentration and measurement of dissociation constants of labeled and unlabeled hormones

It is demonstrated that because of limitations in the magnitude of the specific activity of radiolabeled hormone derivatives, direct binding studies of hormone-receptor interactions of high affinity (10(-9) -10(-11) M, depending on whether 3H- or 123I-labeled hormones are used) will be subject to artifactual distortions due to the need to utilize high concentrations of the receptor. If the concentration of the receptor is not ten times lower than the true affinity constant, the apparent dissociation constant obtained from direct concentration binding curves will vary as a linear function of the receptor concentration. In addition, at high receptor concentrations saturability becomes difficult to demonstrate experimentally and the binding data yield apparently non-hyperbolic, sigmoidal curves which can be mistakenly interpreted to depict cooperative interactions. Similar artifacts related to receptor concentration are predicted for measurements of the hormone concentration dependence of biological proce-ses (e.g. activation of adenylate cyclase, transport processes, etc.). Methods for detecting these effects, and correctly measuring affinities for labeled and unlabeled hormones under these conditions, are described. The implications for measuring the binding properties of hormone-receptor interactions are discussed, especially in reference to studies of the comparative analysis of receptor function in altered metabolic states and to studies relating the biological and binding properties of hormones.

Insulin receptor: covalent labeling and identification of subunits

Two methods were used to label insulin receptors covalently with 125I. In the first, an aryl azide derivative of insulin, 125I-labeled 4-azido-2-nitrophenyl-insulin, was synthesized and used to photolabel the binding region of the insulin receptor in rat liver membranes and human placenta membranes. In the second, insulin receptors were purified from rat liver membranes and labeled with 125I by use of chloramine-T; this method presumably has no specificity for the binding region of the receptor. The proteins labeled by both methods were analyzed by sodium dodecyl sulfate/polyacrylamide gel electrophoresis after or without reduction by dithiothreitol. The photoaffinity label specifically labeled a single band in both liver and placenta that had an apparent molecular weight of 135,000 after reduction. A band with similar mobility was present in the chloramine-T-labeled preparation, which also contained a second major band with an apparent molecular weight of 45,000. Without reduction, both methods resulted in a single labeled band with an apparent molecular weight of about 310,000. These results indicate that the insulin receptor of both liver and placenta has a subunit of molecular weight 135,000 that binds insulin and that the receptor may be composed of at least two different subunits that are linked together or greatly stabilized by disulfide bonds.

Gender differences in the effects of bereavement-related psychological distress in health outcomes

BACKGROUND

This study examined whether traumatic grief, depressive and anxiety symptoms formed three distinct factors for widows and widowers. In addition, we examined whether high symptom levels of traumatic grief, depression and anxiety predicted different mental and physical health outcomes for widows and widowers.

METHOD

Ninety-two future widows and 58 future widowers were interviewed at the time of their spouse's hospital admission and then at 6 weeks, 6, 13 and 25 month follow-ups. Principal axis factor analyses tested the distinctiveness of traumatic grief, depressive and anxiety symptoms, by gender. Repeated measures ANOVA tested for gender differences and changes over time in mean symptom levels of traumatic grief, depression and anxiety. Linear and logistic regression models estimated the effects of high symptom levels of traumatic grief, depression and anxiety at 6 months on health outcomes at 13 and 25 months post-intake by gender.

RESULTS

Three distinct symptom clusters (i.e. traumatic grief, depressive and anxiety symptoms) were found to emerge for both widows and widowers. Widows had higher mean levels of traumatic grief, depressive and anxiety symptoms. High symptom levels of traumatic grief measured at 6 months predicted a physical health event (e.g. cancer, heart attack) at 25 months post-intake for widows. High symptom levels of anxiety measured at 6 months predicted suicidal ideation at 25 months for widowers.

CONCLUSIONS

The results suggest that there are gender differences in the levels of psychological symptoms resulting from bereavement and in their effects on subsequent mental and physical health for widows and widowers.

Laparoscopic versus open donor nephrectomy: comparing ureteral complications in the recipients and improving the laparoscopic technique

BACKGROUND

Laparoscopic live donor nephrectomy (LDN) is a recently developed procedure, the performance of which needs to be studied. Given the reported advantages in the donors, this study looks at graft outcome and ureteral complications in recipients of kidneys procured by open donor nephrectomy (ODN) versus LDN.

METHODS

The LDN recipients consisted of 193 patients since 3/27/96. A total of 168 ODN recipients from 1991 to 1998 served as controls. Immunosuppression protocols were similar for both groups.

RESULTS

Two-year graft survival for LDN and ODN was 98% and 96%, respectively. Two-year patient survival for LDN and ODN was 98% and 97%, respectively. The incidence of delayed graft function and mean serum creatinine at 3 and 12 months was similar in both groups. However, the number of ureteral complications that required operative repair was significantly higher for LDN recipients compared to ODN recipients, 7.7% (n=15) vs. 0.6% (n=1) respectively (P=0.03). Ureteral stenting was required in an additional 3.1% (n=6) of LDN and 2.4% (n=4) of ODN (P=NS). There was, however, a learning curve with time. For the first 130 LDN patients, a total of 20 ureteral complications were recorded, whereas only one occurred in the more recent 63 patients (P=0.03).

CONCLUSIONS

The higher ureteral complication rate in LDN recipients has improved over time as technical causes have been identified. We have noted significant improvement in ureteral viability by using the endogastrointestinal anastomosis instrument on the ureter and peri-ureteral tissue. LDN is therefore an excellent alternative to ODN. Identification of hazards unique to this technique is critical before its broader application.