Cytomegalovirus: the role of CMV post-haematopoietic stem cell transplantation

Human cytomegalovirus (HCMV) is a large DNA virus that is well equipped to evade host immune responses and able to establish lifelong latency. It is able to modulate both innate and adaptive immune reactivity, and has multiple effects on the cell cycle and apoptosis. It is a major opportunistic pathogen in immunocompromised hosts. Reactivation of latent virus may re-stimulate memory T-cell responses that are sufficient to re-establish control over viral replication if the degree of immune suppression is not too great. Following allogeneic transplantation immune responses are often inadequate resulting in progressive tissue damage manifesting as over HCMV disease that usually presents as pneumonitis, colitis or hepatitis. Currently available antiviral pharmacotherapies are limited by toxicities and lack of efficacy in established HCMV disease. Efforts have therefore focused on molecular diagnostic surveillance protocols that allow earlier intervention, and the development of adoptive immunotherapeutic strategies to hasten host immune reconstruction.     

Clinical outcome following nerve allograft transplantation

The clinical outcome of seven patients who underwent reconstruction of long upper- and lower-extremity peripheral nerve gaps with interposition peripheral nerve allografts is reported. Patients were selected for transplantation when the nerve gaps exceeded the length that could be reconstructed with available autograft tissue. Before transplantation, cadaveric allografts were harvested and preserved for 7 days in University of Wisconsin Cold Storage Solution at 5 degrees C. In the interim, patients were started on an immunosuppressive regimen consisting of either cyclosporin A or tacrolimus (FK506), azathioprine, and prednisone. Immunosuppression was discontinued 6 months after regeneration across the allograft(s) was evident. Six patients demonstrated return of motor function and sensation in the affected limb, and one patient experienced rejection of the allograft secondary to subtherapeutic immunosuppression. In addition to providing the ability to restore nerve continuity in severe extremity injuries, successful nerve allografting protocols have direct applicability to composite tissue transplantation.     

Clinical patterns in asthma based on proximal and distal airway nitric oxide categories

Background

The exhaled nitric oxide (eNO) signal is a marker of inflammation, and can be partitioned into proximal [J''aw_NO (nl/s), maximum airway flux] and distal contributions [CA_NO (ppb), distal airway/alveolar NO concentration]. We hypothesized that J''aw_NO and CA_NO are selectively elevated in asthmatics, permitting identification of four inflammatory categories with distinct clinical features.

Methods

In 200 consecutive children with asthma, and 21 non-asthmatic, non-atopic controls, we measured baseline spirometry, bronchodilator response, asthma control and morbidity, atopic status, use of inhaled corticosteroids, and eNO at multiple flows (50, 100, and 200 ml/s) in a cross-sectional study design. A trumpet-shaped axial diffusion model of NO exchange was used to characterize J''aw_NO and CA_NO.

Results

J''aw_NO was not correlated with CA_NO, and thus asthmatic subjects were grouped into four eNO categories based on upper limit thresholds of non-asthmatics for J''aw_NO (≥ 1.5 nl/s) and CA_NO (≥ 2.3 ppb): Type I (normal J''aw_NO and CA_NO), Type II (elevated J''aw_NO and normal CA_NO), Type III (elevated J''aw_NO and CA_NO) and Type IV (normal J''aw_NO and elevated CA_NO). The rate of inhaled corticosteroid use (lowest in Type III) and atopy (highest in Type II) varied significantly amongst the categories influencing J''aw_NO, but was not related to CA_NO, asthma control or morbidity. All categories demonstrated normal to near-normal baseline spirometry; however, only eNO categories with increased CA_NO (III and IV) had significantly worse asthma control and morbidity when compared to categories I and II.

Conclusions

J''aw_NO and CA_NO reveal inflammatory categories in children with asthma that have distinct clinical features including sensitivity to inhaled corticosteroids and atopy. Only categories with increase CA_NO were related to poor asthma control and morbidity independent of baseline spirometry, bronchodilator response, atopic status, or use of inhaled corticosteroids.     

石耳科(子囊菌亚门)的间断分布和替代现象

本文报道了石耳科的两个亚洲的,也是美洲以外的新记录种,即角石耳与深色石耳。进一步证实了单果石耳在南大西洋的,即南美洲和南部非洲的间断分布。对于上述种类以及本科其它一些种类的间断分布和替代现象进行了分析讨论。     

Reflex sympathetic dystrophy syndrome: consensus report of an ad hoc committee of the American Association for Hand Surgery on the definition of reflex sympathetic dystrophy syndrome

This report proposes that reflex sympathetic dystrophy be defined as a pain syndrome in which the pain is accompanied by loss of function and evidence of autonomic dysfunction. In the clinical setting, this diagnosis is usually associated with other anatomic and psychological diagnoses and may be associated with a variety of systemic illnesses and medicolegal factors. All components should be assessed before a treatment plan is established. Priorities should go to emergency care, acute injuries, and systemic illness, psychiatric problems, and chronic anatomic problems, in that order. Early, accurate diagnosis improves prognosis.     

The peripheral nerve allograft: an assessment of regeneration across nerve allografts in rats immunosuppressed with cyclosporin A

Lewis rats (RT1(1] were the recipients of 3-cm nerve grafts from syngeneic Lewis donors or allogeneic ACI (RT1a) donors. Microneurosurgical repair of the nerve graft to the transected sciatic nerve of the recipient animal was performed with 10-0 epineurial sutures. Recipients were randomly allocated to cyclosporin A (CsA) immunosuppressed or untreated groups. Cyclosporin A was administered in the minimal effective dosage to prevent nerve allograft rejection across this major histocompatibility disparity (5 mg/kg per day). Nerve regeneration across the nerve grafts was assessed by sciatic function index (SFI) and toe spread index (TSI) determinations serially and by electrophysiologic, histologic, and morphologic assessments 14 weeks after engraftment. Sciatic nerve regeneration across allogeneic nerve grafts in cyclosporin A immunosuppressed recipients was significantly superior compared to the untreated controls (p less than 0.008) and not significantly different from that across the syngeneic control animals.     

Intermittent compression units for severe post-phlebitic syndrome: a randomized crossover study

BACKGROUND: Although uncommon, severe post-phlebitic syndrome may be associated with persistent, intractable pain and swelling that interfere with work and leisure activities. This study was performed to determine whether intermittent compression therapy with an extremity pump benefits patients with this condition and, if so, whether the benefit is sustained. METHODS: The study was a randomized crossover trial. Over the period 1990 to 1996, all patients in the clinical thromboembolism program of an Ontario teaching hospital who had a history of deep vein thrombosis and intractable symptoms of post-phlebitic syndrome were recruited into the study. The study involved using an extremity pump twice daily for a total of 2 months (20 minutes per session). The patients were randomly assigned to use either a therapeutic pressure (50 mm Hg) or a placebo pressure (15 mm Hg) for the first month. For the second month, the patients used the other pressure. A questionnaire assessing symptoms and functional status served as the primary outcome measure and was administered at the end of each 1-month period. A symptom score was derived by summing the scores for individual questions. At the end of the 2-month study, patients were asked to indicate their treatment preference and to rate the importance of the difference between the 12 pressures. Treatment was considered successful if the patient preferred the therapeutic pressure and stated that he or she would continue using the extremity pump and that the difference between the therapeutic and placebo pressures was of at least slight importance. All other combinations of responses were considered to represent treatment failure. Patients whose treatment was classified as successful were offered the opportunity to keep the pump and to alter pressure, frequency and duration of pump use to optimize symptom management. In July 1996 the authors contacted all study participants whose treatment had been classified as successful to determine whether they were still using the pump and, if so, whether they were still deriving benefit. RESULTS: In total 15 consecutive patients (12 women and 3 men) were enrolled in the study. The symptom scores were significantly better with the therapeutic pressure (mean 16.5) than with the placebo pressure (mean 14.4) (paired t-test, p = 0.007). The treatment for 12 of the patients (80%, 95% confidence interval 52% to 96%) was considered successful. Of these, 9 patients continued to use the pump beyond the crossover study and to derive benefit. INTERPRETATION: The authors conclude that a trial of pump therapy is worthwhile for patients with severe post-phlebitic syndrome and that a sustained beneficial response can be expected in most such patients.