Sindbis virus induces apoptosis through a caspase-dependent, CrmA-sensitive pathway

Sindbis virus infection of cultured cells and of neurons in mouse brains leads to programmed cell death exhibiting the classical characteristics of apoptosis. Although the mechanism by which Sindbis virus activates the cell suicide program is not known, we demonstrate here that Sindbis virus activates caspases, a family of death-inducing proteases, resulting in cleavage of several cellular substrates. To study the role of caspases in virus-induced apoptosis, we determined the effects of specific caspase inhibitors on Sindbis virus-induced cell death. CrmA (a serpin from cowpox virus) and zVAD-FMK (N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone) inhibited Sindbis virus-induced cell death, suggesting that cellular caspases facilitate apoptosis induced by Sindbis virus. Furthermore, CrmA significantly increased the rate of survival of infected mice. These inhibitors appear to protect cells by inhibiting the cellular death pathway rather than impairing virus replication or by inhibiting the nsP2 and capsid viral proteases. The specificity of CrmA indicates that the Sindbis virus-induced death pathway is similar to that induced by Fas or tumor necrosis factor alpha rather than being like the death pathway induced by DNA damage. Taken together, these data suggest a central role for caspases in Sindbis virus-induced apoptosis.

Anatomical basis for nerve injury during laparoscopic hernia repair

One of the most distressing complications of laparoscopic hernia repair is injury to the lateral cutaneous nerve of the thigh. The relation of this nerve to the laparoscopic technique of hernia repair was studied in 50 adult groins. Recommendations for avoidance of injury are delineated based on the anatomical findings.

Role of metal-catalyzed oxidation reactions in the early pathogenesis of scleroderma

The observation that revelation of immunocryptic epitopes in self-antigens may initiate the autoimmune response has prompted the search for processes that induce novel autoantigen structure as potential initiators of autoimmunity. Recent studies have demonstrated that the autoantigens targeted in diffuse scleroderma are unified by their enrichment in nucleolini and by their susceptibility to fragmentation in a novel metal-dependent reaction that requires the generation of reactive oxygen species. Several other studies highlight the importance of reactive oxygen species as mediators of damage during ischemia-reperfusion and present evidence for increased generation of these radicals in patients with scleroderma. Together, these studies suggest a model for the pathogenesis of scleroderma in which metals and free radicals play a central, autoamplifying role.

Stress fracture of the ulna in a female table tennis tournament player

A stress fracture of the diaphyseal ulna occurred in a 19-year-old female competitive table tennis player with a history of secondary amenorrhea. Stress fractures are one of more common problems occurring in vigorous sports. Stress fractures of the ulna can result from any repeated forearm flexor muscle activity. In our case stress was caused by increased athletic activity by additional training twice a day six times a week starting eighth weeks before first signs of pain and by rhythmic repeated submaximal work load in a new job additional to training. Physical training is often associated with menstrual irregularity. Hormonal factors were known for six months. Spontaneous onset of pain in women and previous history of amenorrhea should include stress fractures as differential diagnosis.

Surgical closure of persisting failed tracheoesophageal voice fistula

Tracheoesophageal puncture (TEP) is a highly successful procedure for voice restoration. Occasionally, however, patients fail to achieve satisfactory voice or develop salivary leakage through the fistula into the trachea. Closure of the TEP is then necessary. In most cases, spontaneous closure occurs once the prosthesis has been removed. When the fistula does not close spontaneously, surgical closure is indicated to prevent aspiration and pulmonary complications. We describe a three-layer technique that employs interposition of dermal graft. The technique was used on 14 patients over a 7-year period. Most patients received irradiation to the neck. Complete closure was achieved in 13 of 14 cases; 1 patient developed partial breakdown of the closure. Our technique is relatively easy to perform and has a high success rate (92%). Irradiation did not adversely affect the closure rate.

Unexpected augmentation of mycophenolic acid pharmacokinetics in renal transplant patients receiving tacrolimus and mycophenolate mofetil in combination therapy, and analogous in vitro findings

Mycophenolate mofetil (MMF) a potent immunosuppressive agent, has recently been approved for clinical use (CellCept) in renal transplant patients in combination with cyclosporine (CsA). With the expanded use of tacrolimus (Prograf) as well in renal transplant patients, there is a lack of pharmacokinetic studies clarifying drug interactions between the three agents. A pharmacokinetic study was performed on 18 stable renal transplant patients receiving MMF and tacrolimus together, and four control groups, one receiving tacrolimus alone, two receiving CsA, in combination with MMF (1.0 or 1.5 g bid), and one receiving CsA microemulsion (Neoral). Area-under-the-curve values were calculated for each drug to assess if there was a reciprocal effect on the respective bioavailability of each. In vitro, the immunosuppressive effect of trough level plasma from each patient group was studied using mixed lymphocyte culture (MLC), as well as MLC reactions spiked with various combinations of each drug. There was a minimal effect of MMF on tacrolimus pharmacokinetics. However, patients receiving tacrolimus and MMF displayed significantly higher levels (Cmin and area under the curve) of mycophenolic acid (MPA) than those receiving CsA (Sandimmune or Neoral) and the same dose of MMF (50.2 +/- 16.5 vs 32.1 +/- 16.7 micrograms h/ml AUC, p < 0.02). Equivalent MPA levels could be attained in patients receiving CsA if the MMF dose was increased by 50% (1.5 g bid). There were also significantly lower levels of the glucuronide metabolite of MPA (MPAG) (755 +/- 280 vs 1230 +/- 250 micrograms h/ml AUC, p = 0.02), suggesting a specific inhibition (either direct or indirect) of the conversion of MPA to MPAG in tacrolimus patients, as opposed to those receiving CsA. For each drug combination, there was a positive correlation between the plasma immunosuppressive effect seen in MLC assays and the MMF dose. In addition, trough plasma from patients receiving tacrolimus and MMF was significantly more MLC inhibitory than from those receiving CsA or CsA microemulsion and equivalent-dose MMF. Culture media containing MPA and tacrolimus equal to clinical therapeutic trough concentrations (10 ng/ml) were significantly more MLC inhibitory than CsA at equivalent clinical therapeutic trough concentrations (200 ng/ml) with equivalent MPA levels. These studies in renal transplant patients suggest that tacrolimus in combination with MMF may result in a greater degree of immunosuppression than may be anticipated.

Pressure at residual volume: a useful adjunct to standard fill cystometry

PURPOSE

Determining the role of the bladder in incontinence and/or upper urinary tract deterioration involves the cystometrographic evaluation of detrusor compliance. Management decisions based on information provided by standard fill water cystometry assume that data reflect the physiological state of the patient but this is not always true. We report the use of pressure at residual volume as a physiological measurement to aid in the interpretation of data obtained during standard fill urodynamics.

MATERIALS AND METHODS

All patients presenting to our urodynamic suite for standard cystometry between June 1994 and December 1995 underwent measurement of bladder pressure at insertion of the urodynamic catheter. Residual volume and pressure measured before draining this urine, that is pressure at residual volume, were recorded. The bladder was then filled at a rate equal to or less than 10% per minute of known or predicted capacity. When a volume equal to the residual volume had been instilled, filling pressure was recorded and the remainder of the standard urodynamic evaluation was completed. Uncooperative patients as well as those with an active infection or residual volume less than 10 ml. were excluded from further analysis.

RESULTS

In 152 children pressure at residual volume was compared to filling pressure and the difference was analyzed. Filling pressure was higher than pressure at residual volume in the majority of cases. In 59 children there was a positive change (filling pressure greater than pressure at residual volume) of 5 cm. water or greater and in 13 there was a negative change (pressure at residual volume greater than filling pressure) of 5 cm. water or less. When only cases in which pressure at residual volume was greater than 5 cm. water were analyzed, 46 and 33% had a difference between filling pressure and pressure at residual volume of 5 cm. water or greater and 10 cm. water or greater, respectively.

CONCLUSIONS

Pressure at residual volume is physiological, simple to determine and may provide additional information regarding storage characteristics of the bladder. In the context of the clinical history differences between pressure at residual volume and filling pressure may help to interpret standard fill cystometry data.

The Family Attitude Scale: reliability and validity of a new scale for measuring the emotional climate of families

Research on outcomes from psychiatric disorders has highlighted the importance of expressed emotion (EE), but its cost-effective measurement remains a challenge. This article describes development of the Family Attitude Scale (FAS), a 30-item instrument that can be completed by any informant. Its psychometric characteristics are reported in parents of undergraduate students and in 70 families with a schizophrenic member. The total FAS had high internal consistency in all samples, and reports of angry behaviour in FAS items showed acceptable inter-rater agreement. The FAS was associated with the reported anger, anger expression and anxiety of respondents. Substantial associations between the parents' FAS and the anger and anger expression of students was also observed. Parents of schizophrenic patients had higher FAS scores than parents of students, and the FAS was higher if disorder duration was longer or patient functioning was poorer. Hostility, high criticism and low warmth on the Camberwell Family Interview (CFI) were associated with a more negative FAS. The highest FAS in the family was a good predictor of a highly critical environment on the CFI. The FAS is a reliable and valid indicator of relationship stress and expressed anger that has wide applicability.

Nonseptic lateral sinus thrombosis: the otolaryngologic perspective

Nonseptic lateral sinus thrombosis (NSLST) differs from septic lateral thrombosis (SLST) in that it is not associated with ear or sinus infection, it usually occurs in the adult population, and it has an ambiguous clinical presentation. The otolaryngologist is often consulted about diagnostic findings associated with lateral sinus thrombosis. We report three cases of NSLST that required otolaryngologic assessment. The patients were women, ages 23 to 31 years. Presenting symptoms were headaches in all three patients; one also had concomitant ear pain. Two patients had negative head computed tomography scans; only magnetic resonance imaging was diagnostic. Treatment of NSLST consists of anticoagulation and elimination of predisposing factors. Familiarity with this condition is fundamental for early diagnosis and initiation of appropriate therapy. We discuss the origins and causes of NSLST, clinical presentation, preferred diagnostic strategy, and treatment alternatives.

The effects of chimeric cells following donor bone marrow infusions as detected by PCR-flow assays in kidney transplant recipients

40 recipients of first cadaver kidney transplants were given perioperative donor vertebral bone marrow infusions (DBMC), compared with 100 controls who did not receive donor bone marrow. The immunosuppressive regimen included OKT3, Tacrolimus, and steroid maintenance therapy, and, in some patients, newly introduced mycophenolate mofetil. This report describes the 24-mo actuarial follow-up and several immunological monitoring studies including sequential measurements of donor bone marrow lineage subset chimerism by the recently reported PCR-flow assay. This is a sensitive in situ PCR detection system for donor versus recipient histocompatibility genes as well as cell surface CD epitope markers using flow cytometry. The results indicate (a) the stabilization of the donor CD3+ and CD34+ cells in recipient peripheral blood at levels below 1% between 6 mo and 1 yr postoperatively, with a 10-fold higher level of donor cell chimerism of these lineages in recipient iliac crest marrow; (b) significantly lower levels of chimerism in peripheral blood up to 6 mo postoperatively in patients who had early acute (reversible) rejection episodes compared with those who did not; (c) a higher degree of chimerism seen in patients who were class II MHC HLA DR identical with their donors; (d) the identification of a high proportion of the donor bone marrow derived CD3 dimly staining subset of T cells (to which regulatory functions have been ascribed) in recipient peripheral blood and especially in recipient bone marrow; and (e) an unexpectedly increased susceptibility to clinically significant infections (primarily viral), and even death in the DBMC-infused group, compared with controls, but no graft losses because of rejection in the DBMC-infused group. Mixed lymphocyte culture assays showed a trend toward a greater number of nonspecifically low reactors in the DBMC group, as well as a greater number of nonspecifically high reactors in the controls (P = 0.058). The autologous mixed lymphocyte reaction also indicated a trend towards nonspecific immune activation in the DBMC group. Finally, anti-cytomegaloviral IgG antibody reactivity was significantly inhibited in the DBMC group 4-6 mo postoperatively (P = < 0.05). In the controls, there were no donor cell lineages detected by PCR-flow in the peripheral blood. These rather unexpected findings, indicating a more depressed cellular and humoral immune capacity in the DBMC cadaver kidney transplant recipients in this relatively early follow-up period, are discussed relevant to chimerism, MHC restriction, and suppressor activity brought about by specialized DBMC subsets, which still need to be defined.

Scleroderma autoantigens are uniquely fragmented by metal-catalyzed oxidation reactions: implications for pathogenesis

The observation that revelation of immunocryptic epitopes in self antigens may initiate the autoimmune response has prompted the search for processes which induce novel fragmentation of autoantigens as potential initiators of autoimmunity. The reversible ischemia reperfusion which characterizes scleroderma has focused attention on reactive oxygen species as molecules which might induce autoantigen fragmentation. We demonstrate that several of the autoantigens targeted in diffuse scleroderma are uniquely susceptible to cleavage by reactive oxygen species, in a metal-dependent manner. Multiple features of the fragmentation reaction and its inhibition indicate that these autoantigens possess metal-binding sites, which focus metal-catalyzed oxidation reactions (and consequent fragmentation) to specific regions of the antigens. These data suggest that the autoantibody response in scleroderma is the immune marker of unique protein fragmentation, induced by ischemia reperfusion in the presence of appropriate metals, and focus attention on abnormal metal status as a potential pathogenic principle in this disease.

Macromolecular substrates for the ICE-like proteases during apoptosis

The interleukin-1 beta-converting enzyme (ICE) family of proteases is an important component of the mechanism of the apoptotic process, but the physiologic roles of the different homologs during apoptosis remain unclear. Significant information about the roles of proteolysis in apoptosis will be gained through identification of the distal substrates through which these proteases achieve their pro-apoptotic effects. Identification of these substrates therefore remains an important challenge. A subset of autoantibodies from patients with systemic lupus erythematosus (SLE) recognize molecules that are specifically cleaved early during apoptosis. Several of the identified autoantigens are nuclear proteins (PARP, U1-70 kDa, and DNA-PKcs) that are substrates for CPP32 in vitro and in apoptotic cells. Of note, these substrates are catalytic proteins involved in homeostatic pathways, suggesting that abolition of homeostasis is one fundamental feature ensuring the rapid irreversibility of the apoptotic process. Identification of the other substrates for this protease family will provide the tools to assess the roles of the different proteases in apoptotic death.

Ultraviolet light-induced keratinocyte apoptosis: a potential mechanism for the induction of skin lesions and autoantibody production in LE

Systemic lupus erythematosus (SLE) is a prototype systemic autoimmune disease which is characterized clinically by pleiotropy and periodicity. The immune features which accompany the characteristic flares of the disease have strongly suggested that the autoimmune response is driven by self antigen, and is T cell-dependent. These features have prompted the search for potential initiating process(es) which induce the release of self-antigens in a form which causes T cell tolerance to those self molecules to be broken. We review here several recent observations which implicate apoptotic cells as an important potential source of clustered and concentrated autoantigens in SLE, and present our current model whereby the novel autoantigen fragments generated in apoptotic surface blebs initiate and drive the autoimmune response in this disease.

Human monoclonal antibodies to viral peptides

A new approach to the developing of human monoclonal antibodies to viral peptides is described. The method is based on the positive selection of B cells specific to viral peptides from normal human tissues. To isolate B cells bearing immunoglobulin receptors specific to viral epitopes magnetic beads coated by viral peptides were used. Human B lymphocytes specific to the neutralizing epitope of gp120 of human immunodeficiency virus and to the major epitope of Epstein-Barr nuclear antigen-I were isolated from freshly removed human tonsils. Preselected cells were transformed by Epstein-Barr virus and cultivated on irradiated human embryonic lung fibroblasts in RPMI 1640-OptiMEM medium with 10% fetal calf serum and all necessary supplements. The cultures of B cells producing antibodies to viral epitopes used for selection were obtained. Two cultures secreting IgM antibodies to the peptide MN-24 (neutralizing epitope of immunodeficiency virus) and to the peptide p107 of Epstein-Barr nuclear antigen-1 were expanded, and the specificity of the antibodies and antibody-producing cells was analyzed. The method of positive selection of B cells specific to viral peptides may be used for the preparation of human monoclonal antibodies to viral antigens.

Development of a rapid means of estimating the haemoglobin F content of candidate fetal cells isolated from maternal blood using HPLC

Prenatal diagnosis of genetic disorders in nucleated fetal red blood cells present in maternal blood requires methods to detect and enrich for such cells. Here we describe a rapid high performance liquid chromatography (HPLC) method that allows one to determine as few as 100 cells containing haemoglobin F (HbF) in the presence of a vast excess of haemoglobin A (HbA)-producing cells. The HPLC separations of haemoglobins were performed with a weak cation exchange column-silica gel-bound asparaginic acid-and ammonium phosphate buffer as the mobile phase. Separations were carried out in 7 min. When applied to estimation of the recovery of fetal cells from maternal blood, the HPLC method indicates in a timely manner whether or not to proceed with further techniques (i.e., FISH or PCR). Several current techniques such as Ficoll gradients and fluorescence (FACS) or magnetic (MACS) activated cell sorting were thus evaluated. Unexpectedly, our method indicates high cell losses with both single gradient and triple density Ficoll pre-enrichment methods. Less than 20 per cent of the nucleated red blood cells can be recovered in the most optimal setting. Lysis of erythrocytes may be an alternative technique that leaves nucleated red blood cells of all maturation stages intact. Thus, any further improvements in the technology for fetal cell recovery may be aided by monitoring the yield with HPLC.

Emphysema of the stomach: a roentgenologic alarm. Report of a case and review of the literature

Air within the wall of the stomach is an extremely rare situation with an obscure etiology and a high mortality (43%); only 49 cases have previously been reported in the English language. We present another case, review the relevant literature, and discuss possible-etiologies and treatment.

Methodology of serial ECG classification using an adaptation of the NOVACODE for Q wave myocardial infarction in the Bypass Angioplasty Revascularization Investigation (BARI)

Serial electrocardiographic (ECG) changes are a critical component of the diagnostic algorithm for classification of myocardial ischemic events in large-scale clinical trials. This study describes a computerized serial ECG classification program developed at the St. Louis University Core ECG Laboratory for use in the Bypass Angioplasty Revascularization Investigation (BARI) trial, in which patients with multivessel coronary artery disease were randomized to receive either coronary artery bypass grafting or percutaneous transluminal coronary angioplasty. The St. Louis University program detects and codes serial changes in Q, ST, and T wave items according to Minnesota code (MC) criteria using a modified NOVACODE hierarchical classification system. Measurements using a seven-power calibrated coding loupe are used to generate the MC from a customized software program. Significant minor or major changes are detected by the serial comparison program and referred to a physician coder for verification. Serial comparison coding rules are used to adjust for weaknesses in the standard MC classification system resulting from instability at decision boundaries. Of 4,244 BARI randomized and registry study participants with follow-up ECGs received at the Core ECG Laboratory as of March 1995, a grade 2 MC Q wave progression was noted in 568 participants (13.4%) using MC criteria alone, as compared with 367 (8.6%) after the St. Louis University coding rules were applied. The incidence of grade 1 MC Q wave progressions was 16.4% (697/4,244) versus 6.1% (259/4,244) when the St. Louis University program was applied. Intraobserver variability for grade 2 Q wave progression codes determined from a sample of 812 serial.

In vivo-in vitro correlations with a commercial dissolution simulator. Studies on the H2 receptor antagonist mifentidine

The dissolution profile of mifentidine (CAS 83184-43-4), which is used as an antagonist of histamine at H2 receptors, was determined using a dissolution simulator. The use of an absorption simulator, which is designed to provide an estimate of the optimum sampling scheme for the dissolution simulator, provides useful data for this purpose. Various in vivo-in vitro correlations for mifentidine were examined and were found to be good.