CTLA4-Ig abrogates the anti-globulin response and prolongs cardiac allograft survival after anti-CD2 treatment

CD2 is expressed on T cells and NK cells and is important in T cell activation, making it a potential target for immune intervention. Here, we report a series of experiments aimed at defining the ability of mAbs directed against the CD2 molecule to prevent cardiac allograft rejection in low and high responder rat strain combinations. Administration of the mouse anti-rat CD2 mAbs OX34 or OX55 around the time of transplantation prolonged survival of fully allogeneic Lewis (RT1l) cardiac allografts in low responder DA (RT1a) recipients (MST 14 days for OX55 and >100 days for OX34). Treatment with OX34 prolonged graft survival in the reciprocal high responder DA to Lewis rat strain combination (MST 19 days) and when combined with CTLA4-Ig resulted in long-term graft survival (MST>100 days). Despite these in vivo effects, OX34 had little effect on in vitro assays of lymphocyte activation. Instead, the ability of OX34 to extend allograft survival correlated with T cell depletion. Administration of OX34 induced a similar degree of CD4 T cell depletion in DA and Lewis recipients, but the CD4 depletion observed was more transient in Lewis recipients. Lewis, but not DA strain rats, developed an anti-murine Ig response. Combined treatment with CTLA4-Ig abolished the anti-globulin response to OX34 in Lewis recipients, prolonged circulation of OX34 and increased the extent and duration of CD4 depletion. We conclude that anti-CD2 treatment effectively prolongs cardiac allograft survival and addition of CTLA4-Ig increases its efficacy by abrogating the production of neutralising antibodies.     

Speech-in-noise perception in high-functioning individuals with autism or Asperger's syndrome

BACKGROUND: High-functioning individuals with autism (HFA) or Asperger's syndrome (AS) commonly report difficulties understanding speech in situations where there is background speech or noise. The objective of this study was threefold: (1) to verify the validity of these reports; (2) to quantify the difficulties experienced; and (3) to propose possible mechanisms to explain the perceptual deficits described. METHOD: Speech-in-noise perception abilities were measured using speech reception thresholds (SRTs), defined as the speech-to-noise ratio (SNR) at which approximately 50% of the speech is correctly identified. SRTs were measured for 11 individuals with HFA/AS and 9 age/IQ-matched normal-hearing control subjects, using an adaptive procedure, in a non-reverberant sound-attenuating chamber. The speech materials were standardised lists of everyday sentences spoken by a British male speaker. The background sounds were: (1) a single female talker; (2) a steady speech-shaped noise; (3) a speech-shaped noise with temporal dips; (4) a steady speech-shaped noise with regularly spaced spectral dips; and (5) a speech-shaped noise with temporal and spectral dips. RESULTS: SRTs for the HFA/AS group were generally higher (worse) than those for the controls, across the five background sounds. A statistically significant difference in SRTs between the subject groups was found only for those background sounds that contained temporal or spectro-temporal dips. SRTs for the HFA/AS individuals were 2 to 3.5 dB higher than for the controls, equivalent to a substantial decrease in speech recognition. Expressed another way, the HFA/AS individuals required a higher SNR, whenever there were temporal dips in the background sound, to perform at the same level as the controls. CONCLUSIONS: The results suggest that the speech-in-noise perception difficulties experienced by individuals with autism may be due, in part, to a reduced ability to integrate information from glimpses present in the temporal dips in the noise.     

Function of interstitial cells of Cajal in the rabbit portal vein

Interstitial cells of Cajal (ICCs) were identified in the intact fixed media of the rabbit portal vein (RPV) using c-kit staining. The following experiments were performed using single cell preparations of the enzyme-dispersed vessel. Surviving contacts between the processes of single ICCs and the bodies of smooth muscle cells (SMCs) were observed in electron micrographs and by confocal microscopy. Spontaneous rhythmical [Ca2+]i oscillations were observed in ICCs after loading with the calcium indicator fluo-3 and were associated with depolarizations of the ICCs recorded by tight-seal patch pipette. To investigate signal transmission from ICCs to SMCs in dispersed cell pairs, or within small surviving fragments of the ICC network, an ICC was stimulated under voltage-clamp, while changes in [Ca2+]i in the stimulated cell as well as in a closely adjacent SMC or ICCs were monitored using fast x-y confocal imaging of fluo-3 fluorescence. After stimulation of single voltage-clamped ICC by a depolarizing step similar in duration to depolarizations associated with spontaneous [Ca2+]i oscillations, a depolarization and transient elevation of [Ca2+]i was observed in a closely adjacent SMCs after a delay of up to 4 seconds. In contrast, signal transmission from ICC to ICC was much faster, the delay being less than 200 ms. These results suggest that the an ICC may, in addition to generating an electrical signal (such as a slow wave) and thereby acting as a pacemaker for vascular SMCs of RPV, also release some unknown diffusible substance, which depolarizes the SMCs.     

Elder mistreatment in women

Elder mistreatment is a serious syndrome that affects more than 1.5 million older Americans every year. Actions such as abuse, neglect, exploitation, and abandonment by caregivers, relatives, friends, or acquaintances can have devastating sequelae for the elderly. Such actions may be intentional or unintentional, but the detrimental outcomes for older individuals can destroy the elder's quality of life and health. A lack of empirical research addresses gender differences in elder mistreatment. There is also confusion and debate over what constitutes elder mistreatment in older women versus what is domestic violence that has continued into later life. Professional nurses need to include both types of screening for their older female patients in order to address both types of family violence.     

Salvage radiation for a rising PSA following radical prostatectomy

The purpose of this study was to evaluate the efficacy and complications of postprostatectomy therapeutic irradiation (RT) in patients with known residual disease. Between 1991 and 2003, 170 patients received therapeutic irradiation for a rising PSA following radical prostatectomy. No patients had clinical or radiological evidence of metastatic disease. The median pre-RT PSA level was 1.2 ng/mL (range, 0.2-43 ng/mL). During irradiation, the PSA level was checked weekly (median PSA determinations: 5, range, 2-7). A patient was considered to have a rise/fall of PSA if the level changed by > or = 0.2 ng/mL. There were 149 patients who received photon irradiation (median dose, 6800 cGy) and 21 patients received a combination of photon and neutron irradiation to a median photon dose equivalent of 7800 cGy. A patient was considered to have biochemical failure if his PSA level postnadir was measured at >0.2 ng/mL. Complications were graded according to the RTOG toxicity scale. The median follow-up time was 49 months (range, 1-137 months). Sixty-four patients (38%) had evidence of biochemical failure. The 7 year overall survival was 84%. At 7 years, the actuarial biochemical relapse free survival (bRFS) was 44%. Of the 59 patients with a preradiation PSA <1 ng/mL, the 5 year bRFS was 81%. This compares with 45% for both the PSA 1-4 and PSA >4 ng/mL group (P = 0.00008). The 3-year bRFS rates for patients whose PSA levels increased, decreased, and remained the same during radiation were 20%, 65%, and 76%, respectively (P = 0.0005). Overall survival at 7 years in the decreased PSA group was 88% compared to 67% for those whose PSA level increased (P = 0.43). Thirty-three percent and 19% of the patients experienced Grade 2 genitourinary (GU) and gastrointestinal (GI) complications, respectively. Six percent and 3% of the patients had Grade 3 GU and GI complications, respectively. On univariate and multivariate analysis, the factors significantly associated with a favorable outcome were a declining PSA during RT and a pre-RT PSA <1 ng/mL (P < 0.001). Radiation therapy is an effective treatment modality for select patients with a biochemical recurrence following radical prostatectomy. Patients with a low preradiation PSA level (<1.0 ng/mL) had a significantly better outcome, which supports the early use of therapeutic radiation. The observation that patients with a rising PSA level during treatment do poorly supports the routine practice of monitoring these levels during radiotherapy.     

Initial experience with surgical treatment planning in the newly diagnosed breast cancer patient at high risk for BRCA-1 or BRCA-2 mutation

Despite an abundance of information available for dealing with patients with BRCA-1 and BRCA-2 mutations, little guidance is available to assist the surgeon in dealing with the genetically high-risk patient recently diagnosed with breast cancer. A retrospective review was undertaken of 170 patients who underwent genetic counseling and testing over a 3-year period from March 2000 to March 2003. Forty-three of the 170 patients tested were diagnosed with breast cancer prior to genetic testing. Nine patients (20.9%) tested positive for a deleterious mutation. Fifty-eight percent underwent genetic counseling prior to definitive cancer surgery. Five of the 25 patients who underwent lumpectomy tested positive for a deleterious mutation. Testing results became available during systemic therapy or radiation was delayed until results were known. After counseling, all five patients testing positive went on to bilateral prophylactic mastectomy and reconstruction. None had radiation therapy. Because of a strong family history, eight patients elected to undergo prophylactic mastectomy and reconstruction prior to obtaining genetic test results; and despite compelling histories, all eight tested negative for a mutation. Treatment algorithms are developed to manage patients that are first discovered to be at high risk for a BRCA-1 or BRCA-2 mutation at the time they are diagnosed with breast cancer. Patients diagnosed with breast cancer who are discovered to be at high risk for a genetic mutation should undergo counseling prior to definitive surgery. This maximizes the time that patients have to consider options for prophylaxis and monitoring should their test be positive. It also prevents women who would otherwise be candidates for breast preservation from undergoing unnecessary radiation therapy should they chose prophylactic mastectomy in the face of a positive test.     

A new source of hepatocytes for transplantation

INTRODUCTION: The most effective treatment for acute or chronic liver failure is orthotopic liver transplantation. Worldwide there is a shortage of organs for transplantation. This shortage has called for research into new treatments for management of patients with liver failure. One such treatment is hepatocyte transplantation. During liver resections considerable amounts of normal liver are unavoidably resected. We aim to harvest these hepatocytes and to filter the tumor cells from them to provide a source for transplantation. MATERIALS AND METHODS: After liver resection, the largest vessel at the resected liver edge was identified and cannulated. Seglen's two-stage technique of perfusing the liver with EDTA and collagenase was performed to harvest the hepatocytes. Ep-CAM Ags are consistently present on the surface of epithelial cells and in particular in colorectal cancer cells. Therefore, MOC31 antibodies (selective Abs for Ep-CAM) attached to magnetic beads were used to target the tumor cells. These tumor cells are selectively removed using a magnet. CEA staining was then used to ensure the hepatocyte collection was tumor cell free. Five million hepatocytes were rosetted with one million HT29 CRC cells to assess the immunomagnetic filtration technique. RESULTS: The hepatocyte harvesting resulted in 864,000 viable hepatocytes to be harvested per gram of liver. Histochemical staining using CEA demonstrated 75% of the HT29 cells in the hepatocyte collection were removed after one use of magnetic beads. CONCLUSION: We have demonstrated the successful initial stages of harvesting tumor-free hepatocytes from liver resected for malignancy.     

Serial autofluorescence imaging over two years following indocyanine green-assisted internal limiting membrane peel for macular hole

A 65-year-old patient with an idiopathic full-thickness macular hole underwent a vitrectomy, inner limiting membrane (ILM) peel and gas tamponade. The ILM was stained using 0.5% indocyanine green (ICG). Postoperative autofluorescence imaging shows a central focal hyperfluorescence surrounded by a perifoveal hypofluoresecnt area corresponding to the dyed and peeled ILM. Serial autofluorescence images showed progressive decrease in staining until 2 years later when no signs of ICG autofluorescence were apparent. The visual acuity for this patient improved two Snellen lines from 6/36 to 6/18 at 2 years. ICG may not be clinically toxic as is currently feared.     

Bioactivation of the selective estrogen receptor modulator desmethylated arzoxifene to quinoids: 4'-fluoro substitution prevents quinoid formation

Although selective estrogen receptor modulators (SERMs) are useful in the treatment and prevention of breast cancer, the SERM tamoxifen has been associated with an increased risk of endometrial cancer possibly due to metabolism to electrophilic quinoids. Another SERM, arzoxifene is currently in clinical trials for the treatment of breast cancer, and since it has similar structural characteristics to tamoxifen, it also has the potential to form quinoids. In the current study, the active form of arzoxifene in vivo, desmethylated arzoxifene (DMA), was synthesized and chemically or enzymatically oxidized to DMA diquinone methide. The half-life of DMA diquinone methide at physiological pH and temperature was approximately 15 s. Reaction of DMA diquinone methide with glutathione (GSH) gave four mono-GSH conjugates, two di-GSH conjugates, and one tri-GSH conjugate. In incubations of DMA with GSH and either rat or human liver microsomes, DMA o-quinone-GSH conjugates were detected in addition to DMA diquinone methide-GSH conjugates. A DMA diquinone methide-deoxyguanosine adduct was detected following the incubation of DMA diquinone methide with deoxynucleosides. In preliminary studies with a human breast cancer cell line, DMA induced dose-dependent DNA damage and was more effective at causing DNA damage than raloxifene. These results suggest that DMA can be metabolized to electrophilic/redox-active quinoids, which have the potential to cause toxicity in vivo. A new fluorinated derivative unable to form a diquinone methide, 4'-F-DMA, was synthesized. 4'-F-DMA showed similar estrogen receptor (ER) binding affinity as compared to DMA. The antiestrogenic activity as measured by inhibition of estradiol-mediated induction of alkaline phosphatase activity in Ishikawa cells showed 10-fold lower activity for 4'-F-DMA compared to DMA; however, the antiestrogenic activity was comparable to raloxifene. In microsomal incubations of 4'-F-DMA in the presence of GSH, no GSH adducts were detected. These data suggest that 4'-F-DMA might be a promising SERM with similar activity to DMA and raloxifene and less toxicity.