Follicular T helper cells and humoral reactivity in kidney transplant patients

Memory B cells play a pivotal role in alloreactivity in kidney transplantation. Follicular T helper (Tfh) cells play an important role in the differentiation of B cells into immunoglobulin-producing plasmablasts [through interleukin (IL)-21]. It is unclear to what extent this T cell subset regulates humoral alloreactivity in kidney transplant patients, therefore we investigated the absolute numbers and function of peripheral Tfh cells (CD4^POSCXCR5^POS T cells) in patients before and after transplantation. In addition, we studied their relationship with the presence of donor-specific anti-human leucocyte antigen (HLA) antibodies (DSA), and the presence of Tfh cells in rejection biopsies. After transplantation peripheral Tfh cell numbers remained stable, while their IL-21-producing capacity decreased under immunosuppression. When isolated after transplantation, peripheral Tfh cells still had the capacity to induce B cell differentiation and immunoglobulin production, which could be inhibited by an IL-21-receptor-antagonist. After transplantation the quantity of Tfh cells was the highest in patients with pre-existent DSA. In kidney biopsies taken during rejection, Tfh cells co-localized with B cells and immunoglobulins in follicular-like structures. Our data on Tfh cells in kidney transplantation demonstrate that Tfh cells may mediate humoral alloreactivity, which is also seen in the immunosuppressed milieu.     

Hepatic steatosis in HIV/HCV co-infected patients: correlates, efficacy and outcomes of anti-HCV therapy: a paired liver biopsy study

BACKGROUND/AIMS: Hepatic steatosis is caused by the complex interaction of host and viral factors, such as metabolic syndrome (MS), alcoholism and HCV genotype, and in HIV-HCV co-infected patients, antiretroviral therapy may also play a role. A large population of patients from the AIDS Pegasys Ribavirin International Co-infection Trial (APRICOT) had paired liver biopsies interpreted and graded for steatosis along with lipid measurements and anthropometric data. METHODS: We analyzed these patients to determine the prevalence of steatosis, baseline factors associated with steatosis, effect of steatosis in HCV therapy efficacy and the impact of anti-HCV treatment on steatosis. RESULTS: A total of 65/283 (23%) patients with paired biopsies were positive for steatosis. Patients with steatosis were significantly more likely to have HCV genotype 3, bridging fibrosis/cirrhosis, higher HCV RNA levels, increased triglycerides and lower cholesterol levels. The only different body measurement was neck circumference which was greater in patients with steatosis and significantly decreased from baseline during the study. Hip circumference was predictive of steatosis at baseline. CONCLUSIONS: Factors associated to the metabolic syndrome are important in co-infected patients. Treatment outcome affected steatosis in that viral eradication reduced steatosis in genotype 3 patients, but altogether steatosis did not affect efficacy of treatment in any genotype.     

Low-output syndrome after heart surgery: is a monotherapy with phosphodiesterase-III inhibitors feasible? A comparative study of amrinone and enoximone.

In order to determine whether the primary use of a phosphodiesterase-III (PDE) inhibitor as monotherapy for severe cardiac low-output states (LOS) is in fact practicable, we investigated the haemodynamic effects of amrinone and enoximone in a prospective randomized study. After elective CABG, AVR, or MVR, patients with cardiac LOS were given amrinone (n = 10) or enoximone (n = 9). Following bolus saturation (1.0-2.0 mg/kg [XA = 1.4] or 0.5-1 mg/kg [XE = 0.9] in total), a dose of 5-10 microgram/kg/min was given by infusion. The standard monitoring program included discontinuous haemodynamic measurements (Swan-Ganz) over a maximum time period of 48 hours, arterial and venous blood-gas analyses, and clinical chemistry. The preoperative clinical and haemodynamic status of the enoximone (E) group (55% CABG patients; MPAP 27 +/- 2.5 mmHg, PCWP 20 +/- 2.9 mmHg, PVR 201 +/- 35 dyn.s.cm-5) was considerably worse than that of the amrinone (A) group (70% CABG patients; MPAP 23 +/- 2.3 mmHg, PCWP 16 +/- 3.5 mmHg, PVR 153 +/- 28 dyn.s.cm-5). Both PDE inhibitor preparations led to a significant increase in cardiac index (from 1.9 +/- 0.1 to 2.5 +/- 0.12 L/min/m2 (A) and from 1.98 +/- 0.1 to 2.6 +/- 0.18 L/min/m2 (E) within 30 minutes, accompanied by a simultaneous decrease in filling pressures and vascular resistances. For up to 2 hours, 3/10 (A) and 2/9 (E) patients required additional positive inotropic support with adrenaline. There were no significant differences between the two groups at any time.(ABSTRACT TRUNCATED AT 250 WORDS)     

Homologous desensitization of human corticotropin-releasing factor, receptor in stable transfected mouse fibroblast cells

Previous radioligand binding and second messenger studies have shown that corticotropin-releasing factor (CRF) modulates its receptor following both in vivo and in vitro treatment. In the present study, we determined the sequence of events leading to CRF-induced downregulation and desensitization of cloned CRF receptors in murine fibroblast cells (Ltk⁻) stably transfected with CRF, DNA (from human pituitary). Treatment of cells with rat/human CRF produced a dose- and time-dependent decrease in [¹²⁵I]Tyr^o-ovine CRF ([¹²⁵I]oCRF) binding and a concomitant decrease in CRF-stimulated adenylate cyclase activity. Significant decreases in [¹²⁵I]oCRF binding and agonist-stimulated cAMP production were evident minutes after CRF treatment with maximal (60–80%) reductions seen following 1 h of CRF treatment. Scatchard analysis revealed that the decrease in [¹²⁵I]oCRF binding was due to the downregulation of the receptor with no significant alteration seen in the affinity of the ligand. Since the transfected cell line is engineered using an artificial promoter, we did not detect any significant changes in CRF₁ receptor mRNA levels following CRF treatment for up to 24 h.     

Ambulante Hernioplastik nach Lichtenstein

Zusammenfassung Die Lichtenstein-Operation ist eine hervorragende und einfache Technik zur ambulanten Leistenbruchversorgung. Die vorliegende Studie umfasst 500 ambulante Leistenbruchoperationen in einem Zeitraum von 1994 bis 2002. Nach durchschnittlich 2 Jahren (6–86 Monate) konnten 84,6% der Patienten persönlich nachuntersucht werden. Schwere Komplikationen gab es keine. Die Anzahl der revisionsbedürftigen Hämatome war mit n=6 (1,2%) niedrig wie die der Hodenatrophie n=1 (0,2%) und der tiefen Wundinfekte n=1 (0,2%). Eine Thrombose gab es nicht. Die Rezidivrate (n=15) betrug 3,5%. 96% der Patienten würden den Eingriff wieder ambulant durchführen lassen.Bei tageschirurgischen Eingriffen sollte der Chirurg präoperativ sorgfältig das häusliche Umfeld und die postoperative Nachbehandlung abklären. Unsere Ergebnisse zeigen, dass die Anzahl ambulanter Herniotomien bei einem entsprechend selektionierten Krankengut ohne Gefahr ernsthafter Komplikationen problemlos unter Vollnarkose durchgeführt werden kann. Eine Zunahme ambulanter Operationen könnte zu einer deutlichen Kostenreduzierung im Gesundheitswesen führen.