The role of adipokines in the rapid antidepressant effects of ketamine.

We previously found that body mass index (BMI) strongly predicted response to ketamine. Adipokines have a key role in metabolism (including BMI). They directly regulate inflammation and neuroplasticity pathways and also influence insulin sensitivity, bone metabolism and sympathetic outflow; all of these have been implicated in mood disorders. Here, we sought to examine the role of three key adipokines-adiponectin, resistin and leptin-as potential predictors of response to ketamine or as possible transducers of its therapeutic effects. Eighty treatment-resistant subjects who met DSM-IV criteria for either major depressive disorder (MDD) or bipolar disorder I/II and who were currently experiencing a major depressive episode received a single ketamine infusion (0.5 mg kg-1 for 40 min). Plasma adipokine levels were measured at three time points (pre-infusion baseline, 230 min post infusion and day 1 post infusion). Overall improvement and response were assessed using percent change from baseline on the Montgomery-Asberg Depression Rating Scale and the Hamilton Depression Rating Scale. Lower baseline levels of adiponectin significantly predicted ketamine's antidepressant efficacy, suggesting an adverse metabolic state. Because adiponectin significantly improves insulin sensitivity and has potent anti-inflammatory effects, this finding suggests that specific systemic abnormalities might predict positive response to ketamine. A ketamine-induced decrease in resistin was also observed; because resistin is a potent pro-inflammatory compound, this decrease suggests that ketamine's anti-inflammatory effects may be transduced, in part, by its impact on resistin. Overall, the findings suggest that adipokines may either predict response to ketamine or have a role in its possible therapeutic effects.

cAMP signaling in brain is decreased in unmedicated depressed patients and increased by treatment with a selective serotonin reuptake inhibitor.

Basic studies exploring the importance of the cyclic adenosine monophosphate (cAMP) cascade in major depressive disorder (MDD) have noted that the cAMP cascade is downregulated in MDD and upregulated by antidepressant treatment. We investigated cAMP cascade activity by using 11C-(R)-rolipram to image phosphodiesterase-4 (PDE4) in unmedicated MDD patients and after ~8 weeks of treatment with a selective serotonin reuptake inhibitor (SSRI). 11C-(R)-rolipram positron emission tomographic (PET) scans were performed in 44 unmedicated patients during a major depressive episode and 35 healthy controls. Twenty-three of the 44 patients had a follow-up 11C-(R)-rolipram PET scan ~8 weeks after treatment with an SSRI. Patients were moderately depressed (Montgomery-Åsberg Depression Rating Scale=30±6) and about half were treatment naïve. 11C-(R)-rolipram binding was measured using arterial sampling to correct for individual differences in radioligand metabolism. We found in unmedicated MDD patients widespread, ~20% reductions in 11C-(R)-rolipram binding compared with controls (P=0.001). SSRI treatment significantly increased rolipram binding (12%, P<0.001), with significantly greater increases observed in older patients (P<0.001). Rolipram binding did not correlate with severity of baseline symptoms, and increased rolipram binding during treatment did not correlate with symptom improvement. In brief, consistent with the results of basic studies, PDE4 was decreased in unmedicated MDD patients and increased after SSRI treatment. The lack of correlation between PDE4 binding and depressive symptoms could reflect the heterogeneity of the disease and/or the heterogeneity of the target, given that PDE4 has four subtypes. These results suggest that PDE4 inhibitors, which increase cAMP cascade activity, may have antidepressant effects.

Baseline vitamin B12 and folate levels do not predict improvement in depression after a single infusion of ketamine.

INTRODUCTION: Deficiencies in both vitamin B12 and folate have been associated with depression. Recently, higher baseline vitamin B12 levels were observed in individuals with bipolar depression who responded to the antidepressant ketamine at 7 days post-infusion. This study sought to -replicate this result by correlating peripheral vitamin levels with ketamine's antidepressant efficacy in bipolar depression and major depressive disorder (MDD). METHODS: Baseline vitamin B12 and folate levels were obtained in 49 inpatients with treatment-resistant MDD and 34 inpatients with treatment-resistant bipolar depression currently experiencing a major depressive episode. All subjects received a single intravenous ketamine infusion. Post-hoc Pearson correlations were performed between baseline vitamin B12 and folate levels, as well as antidepressant response assessed by percent change in Hamilton Depression Rating Scale (HDRS) scores from baseline to 230 min, 1 day, and 7 days post-infusion. RESULTS: No significant correlation was observed between baseline vitamin B12 or folate and percent change in HDRS for any of the 3 time points in either MDD or bipolar depression. DISCUSSION: Ketamine's antidepressant efficacy may occur independently of baseline peripheral vitamin levels.

Excluding medical and haematological conditions as a cause of bruising in suspected non-accidental injury.

A mistaken diagnosis of child abuse can occur in a number of medical conditions, many of which can be readily diagnosed by experienced paediatricians. Bleeding disorders offer a greater challenge, especially when court proceedings may demand their exclusion. Some of these disorders are rare but more prevalent in areas which have a high incidence of consanguinity. We advocate two stages of laboratory investigations but the limitations of some of these tests and their inability to exclude a bleeding disorder with absolute certainty should be recognised. However, if personal and family histories are absent and both first-stage and second-stage investigations are normal, it is highly unlikely that a bleeding disorder will be missed.

Angiotensin II type 2 receptor-mediated apoptosis of cultured neurons from newborn rat brain.

Angiotensin II (Ang II) type 2 (AT2) receptors are highly expressed in neonate brain and may have a role in developmental processes such as apoptosis. Concurrent activation of c-Jun N-terminal kinase (JNK) and inhibition of Erk mitogen-activated protein kinase activities is important for apoptosis in many cells, and we previously demonstrated that stimulation of AT2 receptors causes decreased mitogen-activated protein kinase activity in neurons cultured from newborn rat hypothalamus and brain stem. Using such cultures we have employed terminal deoxynucleotidyl transferase-mediated deoxy-UTP nick end labeling and internucleosomal DNA fragmentation to assess the role of AT2 receptors in neuronal apoptosis. Ang II (100 nM; 4-72 h) alone produced no significant neuronal apoptosis, and AT2 receptor activation did not stimulate JNK activity. However, exposure of cultures to UV radiation (6 J/m2/sec for 4 sec) to stimulate JNK elicited neuronal apoptosis that was significantly enhanced by Ang II, an effect that was abolished by the AT2 receptor antagonist PD 123,319 (1 microM) or the serine/threonine phosphatase inhibitor okadaic acid (3 nM). Additionally, Ang II enhanced the UV radiation-induced decrease in the levels of the DNA repair enzyme poly-(ADP-ribose) polymerase. These data indicate that Ang II, via AT2 receptors and activation of a serine/threonine phosphatase, contributes to neuronal apoptosis.

Central pressor action of neurotensin in conscious rats.

The effects of neurotensin upon blood pressure in conscious rats were examined after intracerebroventricular (i.v.t.) or intravenous (i.v.) administration of this peptide. Whereas i.v. injected neurotensin (0.1-2.0 microgram/kg) was depressor, i.v.t. injected neurotensin (1 microgram and above) was pressor. Peripheral depressor responses could not be repeated in the same animal due to tachyphylaxis, but central pressor responses were repeatable without reduction in magnitude, showing that the two effects were separate entities. Thyrotropin-releasing hormone (TRH), which is reported to be a potent neurotensin antagonist, completely abolished the neurotensin depressor response, and attenuated the central pressor action. TRH did not alter the central pressor effect of another peptide, angiotensin II (AII). The potent AII receptor antagonist saralasin, while abolishing the central pressor effect of AII, was completely without effect upon the neurotensin-induced pressor response. These results indicate that i.v.t. injected neurotensin and AII stimulate a rise in blood pressure via different receptors. The alpha-adrenergic antagonists phentolamine, prazosin, or yohimbine (injected i.v.t.) involvement of the sympathetic nervous system in this response. These results are discussed in relation to the central pressor actions of other neuropeptides.

Inhibition of central angiotensin responses by angiotensin type-1 receptor antibody.

Angiotensin type-1 receptor subtypes (AT1) are implicated in the physiological actions of angiotensin II in the brain. In the present study we used an AT1 receptor antibody and a polymerase chain reaction--synthesized AT1 receptor complementary DNA to show that the hypothalamus expresses significantly higher levels of AT1 receptor messenger RNA and protein compared with the brain stem. Intracerebroventricular injections of AT1-specific antibody blocks the dipsogenic and blood pressure responses induced by centrally injected angiotensin II. These results demonstrate the expression of AT1 receptor gene in the brain and that the AT1 receptor antibody is able to inhibit the physiological responses of angiotensin II mediated by the brain.

Angiotensin II type 1 receptor-modulated signaling pathways in neurons.

Mammalian brain contains high densities of angiotensin II (Ang II) type 1 (AT1) receptors, localized mainly to specific nuclei within the hypothalamus and brainstem regions. Neuronal AT1 receptors within these areas mediate the stimulatory actions of central Ang II on blood pressure, water and sodium intake, and vasopressin secretion, effects that involve the modulation of brain noradrenergic pathways. This review focuses on the intracellular events that mediate the functional effects of Ang II in neurons, via AT1 receptors. The signaling pathways involved in short-term changes in neuronal activity, membrane ionic currents, norepinephrine (NE) release, and longer-term neuromodulatory actions of Ang II are discussed. It will be apparent from this discussion that the signaling pathways involved in these events are often distinct.

Early induction and augmentation of parasitic antigen-specific antibody-producing B lymphocytes in the non-Peyer's patch region of the small intestine.

In this study, B lymphocytes from the small intestine of immunized rats were examined for their expression of specific antibodies against Trichinella spiralis (TS) antigen. The isotypes of the antigen-specific antibodies on B cells were examined via immunofluorescence microscopy. Monoclonal mouse anti-rat IgE, IgG1, IgG2a, IgG2b, IgG2c, IgA and IgM primary antibodies in conjunction with FITC-conjugated goat anti-mouse Ig secondary antibody and XRITC-conjugated 9D4 T. spiralis antigen were used to study the dynamics of the appearance of activated B lymphocytes in the small intestine, Peyer's patch, both the germinal center (PP-GC) and the non-germinal center (PP-NGC), the mesenteric lymph node (MLN), and the spleen. The results demonstrate that activated B cells are elicited by TS in the non-Peyer's patch region of the small intestine to express all isotypes of antibodies against TS antigen. IgG- and IgE-producing cells (Ab-PC) began proliferation only 1 and 2 days after infection, respectively. The strongest response was mounted by the IgE-PC in the lamina propria of the intestine. The response by IgA-PC generated was not only significantly delayed and also much weaker than that of the IgE- and IgG-PC. Peyer's patches failed to be a significant contributor in this immune response. Although this antigen-specific immune response was produced in the MLN and the spleen, it was weaker than that of the small intestine. The study indicates the potential ability of an immunized host to generate an early, yet effective, humoral immunity against T. spiralis in the non-Peyer's patch region of the small intestine."

Modulation of angiotensin II type 2 receptor mRNA in rat hypothalamus and brainstem neuronal cultures by growth factors.

This study investigates the regulatory effects of growth factors upon angiotensin II type 2 (AT2) mRNA levels in neurons co-cultured from newborn rat hypothalamus and brainstem. Incubation of cultured neurons with nerve growth factor (NGF; 5-50 ng/ml) caused time-dependent changes in the steady-state levels of AT2 receptor mRNA. Short-term (0.5-1.0 h) incubations with NGF resulted in significant increases in AT2 receptor mRNA, whereas longer-term incubations (4-24 h) caused significant decreases. Activation of NGF receptors is known to stimulate phospholipase C-gamma and subsequently activate protein kinase C (PKC). Incubation of cultures with the PKC activator, phorbol-12-myristate-13-acetate (PMA; 100 nM), caused temporal changes in AT2 receptor mRNA levels similar to those observed with NGF. By contrast, insulin (0.1-10 microg/ml) elicited only significant decreases in AT2 receptor mRNA levels. The observed abilities of NGF and insulin to regulate the expression of AT2 receptor mRNA are consistent with the fact that the AT2 receptor gene promoter region contains several cis DNA regulatory elements that respond to growth factor-stimulated transcription factors. These novel observations which show that NGF and insulin can regulate AT2 receptor mRNA in neurons derived from neonatal rat CNS lend support to the idea that AT2 receptors have a role in development and differentiation.

High-dose carmustine, etoposide and melphalan ('BEM') with autologous stem cell transplantation: a dose-toxicity study.

We have investigated the toxicity of dose-escalation of BCNU, etoposide and melphalan ('BEM') chemotherapy with autologous stem cell transplantation in patients with haematological malignancies. Seventy-two patients with haematological malignancies were treated with BCNU (600 mg/m2, 450 mg/m2 or 300 mg/m2), etoposide 2 g/m2 and melphalan 140 mg/m2 followed by autologous bone marrow transplantation (ABMT), n = 51, or autologous peripheral blood progenitor cell transplantation (APBPCT), n = 21. Liver and pulmonary function was monitored pretransplant and at regular intervals post-transplant. Mucositis was graded daily during in-patient stay. There was a significantly higher incidence of symptomatic pulmonary toxicity in the patients who received BCNU at 600 mg/m2 than in the other two groups, and there was a significant increase in the incidence of asymptomatic decrease in carbon monoxide (KCO) in the patients who received BCNU 450 mg/m2. There was no significant difference between the three groups in the incidence and severity of mucositis or in the incidence of transiently abnormal liver function. We conclude that etoposide at 2 g/m2 can be used without unacceptable mucositis. BCNU at 600 mg/m2 is associated with an unacceptably high incidence of lung toxicity, but at 450 mg/m2 there is minimal symptomatic lung toxicity.

Peripheral blood stem cell transplantation after high-dose therapy in patients with malignant lymphoma: a retrospective comparison with autologous bone marrow transplantation.

We report the results of peripheral blood progenitor cell (PBPC) harvesting in 22 patients with lymphoma who underwent leucapheresis after cells were mobilised using 3 g/m2 cyclophosphamide and G-CSF. In 19 patients, the total CFU-GM collected was greater than 7.5 x 10(4)/kg. These patients underwent successful autologous PBPC transplantation. This group of patients was compared to a historical group of 24 patients with lymphoma who underwent ABMT with the same conditioning chemotherapy. The time to engraftment of neutrophils to 0.5 x 10(9)/l was significantly reduced (median 11 days vs 19 days, P < 0.0001) and consequently in-patient stay was reduced (median 21 days vs 28 days, P < 0.001). Blood product support (median 3 vs 4 units blood, P = 0.02; median 15 vs 40 units platelets, P = 0.005) and use of TPN (median 0 days vs 8 days, P < 0.001) were reduced. We estimate a saving of approximately pounds 2370 per patient using PBPC for autologous transplantation compared to bone marrow progenitor cells. This saving is significant (P < 0.001).

Measurement of reticulated platelets following peripheral blood progenitor cell and bone marrow transplantation: implications for marrow reconstitution and the use of thrombopoietin.

Neutrophil and platelet engraftment times are significantly shorter in patients undergoing PBPCT compared with ABMT. The explanation for this is unclear. The reticulated platelet percentage (RP%) has been established as a measure of bone marrow platelet production. Using this measurement we have followed thrombopoiesis over the transplant period in 10 patients undergoing PBPCT, eight ABMT and four alloBMT. Neutrophil and platelet engraftment times were significantly shorter in patients undergoing PBPCT than either ABMT or alloBMT. The RP% fell to a nadir in parallel with the platelet count in all patients following conditioning therapy consistent with an aplastic state and rose before platelet recovery as young platelets were released. The peak rise in the RP% was significantly greater and occurred earlier in PBPCT compared with BMT. The total number of reticulated platelets released during the time of engraftment was significantly greater in PBPCT than BMT. The potential role of the RP% in the timing of thrombopoietin therapy is explored. Finally the diagnostic use of the RP% in post-transplant thrombocytopenia is illustrated by a case in which a persistently high RP% accurately predicted a consumptive aetiology.

Immunohistochemical mapping of angiotensin AT1 receptors in the brain.

A new approach to study angiotensin receptor distribution in the brain has been taken by developing antibodies to partial sequence of the angiotensin II (AII) type-1 receptor subtype (AT1) and demonstrating the presence of receptors with immunohistochemical staining. The antibody to a portion of the 3rd cytoplasmic loop of the AT1 receptor revealed distinctive punctate immunoreactive staining on cell bodies. The cell bodies were distributed in the forebrain in paraventricular and supraoptic nuclei, the organum vasculosum lamina terminalis, median preoptic area and subfornical organ. In the brainstem, the entire locus coeruleus was stained, together with the adjacent mesencephalic and motor nuclei of the trigeminal nerve. The auditory system including the cochlear nucleus and superior olivary nuclei were stained. In the medulla, all the structures involved in blood pressure control were stained including the nucleus of the solitary tract, the 12th nerve nuclei, the rostroventral lateral area and the nucleus ambiguous. Sites where AT2 receptors are located were not stained or staining was limited to specific area such as the medial accessory nucleus of the inferior olive. Immunocytochemical staining of AT1 receptors provides a new and more precise approach to the cellular localization of AII receptors.

Angiotensin II type 2 receptor expression in neuronal cultures from spontaneously hypertensive rat brain.

We have compared the levels of angiotensin II (AII) type 2 (AT2) receptors in neuronal cultures from 1-day-old Wistar Kyoto (WKY) and spontaneously hypertensive (SH) rat hypothalamus and brainstem. These studies were performed to determine if the increase in total AII receptors observed in SH neurons in previous studies includes the AT2 receptor subtype. Specific binding of the AT2 receptor selective ligand [125I]CGP42112 to WKY and SH rat neuronal cultures was time dependent and saturable in each case. Kd (approximately 0.35 nM) and Bmax (approximately 95 fmol/mg protein) values for [125I]CGP42112 specific binding did not significantly differ between WKY and SH rat cultures. In addition, AT2 receptor-mediated reductions in cellular cGMP exhibited no significant differences in WKY and SH rat neuronal cultures. We conclude that the greater levels of AII receptors found in SH rat hypothalamus/brainstem neuronal cultures, compared with WKY rat neurons from these areas, do not include the AT2 receptor subtype.

Difficulty in the staging of Hodgkin's disease due to the coexistence of reactive lymphadenopathy.

We report a patient in whom Stage 1A Hodgkin's Disease was established by lymph node biopsy and radiology. Further lymphadenopathy developed accompanied by sweats and fever. Initially this was thought to represent further extensive Hodgkin's disease however repeat biopsy of the newly enlarged nodes showed reactive changes only. We discuss the importance of histological staging in this disease.

High Dose, Short Duration Combination Chemotherapy (MEGA III) for Patients with High Grade Poor Prognosis Non-Hodgkin's Lymphoma-A Phase I/II Study.

16 patients with histologically high grade poor prognosis non-Hodgkin's lymphoma were treated with high-dose, short duration combination chemotherapy (MEGA III). 14 patients had de novo disease and 2 patients primary refractory lymphoma. The 2 patients with primary refractory disease both died, 1 of disease progression and 1 of toxicity of the regimen. However, the complete response rate observed among the 14 de novo patients was nearly 85%. With a maximum follow-up period of 20 months, 2 patients have relapsed, one after 6 months and another after 7 months respectively. Toxicities were common and mainly related to mucositis and pancytopenia. The use of haemopoietic growth factors in these patients to shorten the periods of pancytopenia may reduce the mortality and morbidity of this regimen and should be explored.

Ischaemic retinopathy occurring in patients receiving bone marrow allografts and campath-1G: a clinicopathological study.

AIMS/BACKGROUND: Ischaemic retinopathy is a well characterised complication of bone marrow transplantation (BMT). Although the aetiology is unclear, it is most probably multifactorial, and may be related to treatment such as radiation and cyclosporin A. The clinical findings are reported of two patients who developed such a retinopathy and the ocular histology from one of these cases is presented. METHODS: Two patients underwent BMT for acute lymphoblastic leukaemia, receiving campath-1G for prophylaxis against graft versus host disease, and showed fundal changes compatible with BMT retinopathy. The eyes from one patient were retrieved at post mortem and examined by both light and electron microscopy. RESULTS: The visual symptoms and fundal signs resolved spontaneously with no specific treatment in one patient. Light and electron microscopic examination of the eyes of the other patient was compatible with an ischaemic aetiology and showed evidence of retinal capillary endothelial loss. CONCLUSIONS: (i) Histopathology in one case of BMT retinopathy demonstrates a retinal endotheliopathy similar to that described in radiation retinopathy. (ii) BMT retinopathy may occur in the absence of cyclosporin A treatment. (iii) The retinopathy can recover spontaneously with no specific treatment.

Separation and quantification of murein and precursors from Enterobacter cloacae after treatment with trimethoprim and sulphadiazine.

The intracellular concentrations of the soluble murein precursors UDP-Mur-NAc-pentapeptide in the cytoplasm, the membrane-bound lipid precursor disaccharide pentapeptide and the muropeptides of Enterobacter cloacae cultures treated with trimethoprim (12.5 micrograms mL-1) and sulphadiazine (250 micrograms mL-1) were determined by using capillary zone electrophoresis analysis. In the presence of trimethoprim, UDP-Mur-NAc-pentapeptide as well as disaccharide pentapeptide accumulated. In the case of sulphadiazine-treated cells, the concentration of UDP-Mur-NAc-pentapeptide roughly paralleled the control cells but sulphadiazine caused a slow incremental accumulation of disaccharide pentapeptide. The muropeptide composition of the murein indicated that the differences between the peptidoglycans produced by the control cells and the cells grown in the presence of either trimethoprim or sulphadiazine alone or in combination were quite marked. The results suggest that the enhanced activity of trimethoprim plus sulphadiazine against E. cloacae is caused by an additional effect on the inhibition of the bacterial peptidoglycan biosynthesis and that this additional effect is a fundamental part of the antibacterial action of the antimetabolites. This effect leads to changes of cell morphology and resultant changes in bacterial cell permeability.