N-terminus of Etanercept is Proteolytically Processed by Dipeptidyl Peptidase-4

Pharmaceutical Research - Biologics are structurally heterogeneous and can undergo biotransformation in the body. Etanercept (ETN) is a fusion protein composed of a soluble tumor necrosis factor...     

Reversible altered consciousness with brain atrophy caused by valproic acid

A 5-year-old female developed alteration of consciousness during 3 days of long-term treatment with valproic acid for localization-related epilepsy. Computed tomography revealed cerebral atrophy, and electroencephalography presented slow background activity. Consciousness cleared only 12 hours after valproic acid was discontinued, and normal electroencephalography results were evident 1 week later. Cerebral atrophy was nonexistent 2 months later. This rapidly developing but reversible alteration of consciousness in parallel with brain atrophy is recognized as a rare idiosyncratic adverse effect of valproic acid.     

Cortical myoclonus in children

Cortical myoclonus is a distinct clinical condition that can be defined electrophysiologically, and occurs in both children and adults. It is well known that patients sometimes exhibit stimulus-sensitive jerks and giant somatosensory-evoked potentials (SEPs). In contrast, imaging abnormalities are less prominent in many patients. Reports focusing on cortical myoclonus, except for epilepsia partialis continua, in childhood have been limited in Japan. One reason for this could be that Japanese pediatric neurologists are not familiar with the backaveraging technique. We describe the clinical and physiological features of cortical myoclonus in ten children. Routine EEG, EEG backaveraging, SEP measurement, CT/MRI (computed tomography/magnetic resonance imaging), and TMS (transcranial magnetic stimulation) were performed. All patients exhibited clear evidence of cortical myoclonus. In six patients, backaveraging was necessary since spikes were absent on routine EEG. A cortical source of the myoclonus was further supported by a TMS study performed on four patients. The etiologies of the myoclonus were diverse, cerebrovascular disease being the most common (three patients). Stimulus-sensitive or action-induced jerks were observed in three patients. Cortical SEPs were enlarged in one patient, and reduced or absent in six. Lesions were found on CT/MRI in nine patients, in five of whom the margin of the lesion was within, or adjacent to, the sensorimotor cortex. Complete destruction of the sensorimotor cortex was not observed. It was suggested that cortical neurons in the vicinity of a lesion, rather than in the lesion itself, play a role in the generation of focal myoclonus.     

An autopsy case of ornithine transcarbamylase deficiency

We present an autopsy case of ornithine transcarbamylase (OTC) deficiency with grumose degeneration in the dentate nucleus of the cerebellum. The patient had intractable neonatal convulsions and hyperammonemia from the 3rd day after birth. Diagnosis of OTC deficiency was made based on null activity of the enzyme and four-base deletions in exon 9 of the OTC gene. Death was due to sepsis as well as disseminated intravascular coagulation at 1 year and 2 months of age. Neuropathology showed multiple cystic changes and ulegyria in the bilateral frontal and parietal lobes. Multiple cysts were associated with the region, which was infiltrated with macrophages surrounded by astroglia showing palisading pattern. Ferrugination was marked in the thalamus and severe neuronal loss with astrogliotic change in the CA1-2 area of the hippocampus. Grumose degeneration was noted in the dentate nucleus of the cerebellum. This is the first report of grumose degeneration in OTC deficiency.     

Alterations of immune functions in barrier disrupted skin by UVB irradiation

BACKGROUND: While immunologic events elicited by acute barrier disruption or UVB irradiation have been studied in detail, the biological sequel of multiple insults to the skin is not well understood. OBJECTIVE: Since the skin would receive a variety of simultaneous stimuli in daily life, we tested the effects of sequential treatments with barrier disruption and UVB exposure on skin immunity. METHODS: Earlobes of BALB/c mice received tape-stripping and subsequently low-dose UVB exposure. Control mice were treated with either tape-stripping or UVB. The expression of surface markers and cytokine production in Langerhans cells and keratinocytes and the elicitation response of contact hypersensitivity were compared. RESULTS: By flow cytometry, tape-stripping augmented the expression of MHC class II, CD54, CD80, CD86 and CD40 on Langerhans cells, whereas UVB decreased the expression of some of these molecules. Combination of tape-stripping and UVB induced largely intermediate levels between these two. Upon stimulation with L cells expressing CD40L, Langerhans cells from tape-stripped and UVB-irradiated earlobes strongly transcribed mRNA for interleukin-1beta compared to each treatment. In keratinocytes, tape-stripping or UVB slightly upregulated tumor necrosis factor-alpha and interleukin-1alpha production at both mRNA and protein levels, whereas these two treatments synergistically increased the production of these cytokines. The in vitro hapten-presenting ability of Langerhans cells to trinitrophenyl-immune lymph node T cells ranked first in tape-stripping, second in tape-stripping plus UVB and third in UVB, and so did the intensity of elicitation responses in contact hypersensitivity to a hapten, picryl chloride. CONCLUSION: It is suggested that barrier disruption and UVB antagonize with each other in contact hypersensitivity as a reflection of their effects on Langerhans cell antigen-presenting function, but they synergize in cytokine production by both Langerhans cells and keratinocytes.     

Bucillamine-induced toxic epidermal necrolysis and fixed drug eruption

We report two cases of bucillamine-induced bullous reactions with keratinocyte necrosis. The first patient, a 27-year-old woman, developed toxic epidermal necrolysis (TEN) over her whole body after taking bucillamine 300 mg/day for seven days. The second patient, a 63-year-old woman, developed several bullous erythemas on the mucous membranes and legs after taking bucillamine for more than two years. The fixed drug eruptions were diagnosed based on a provocation test in addition to clinical and histopathologic findings. These cases highlight the importance of considering fixed drug eruption as well as TEN in the differential diagnosis of bucillamine-induced bullous drug eruption.     

Effect of enteral versus parenteral nutrition on inflammation and cardiac function in a rat model of endotoxin-induced sepsis

The present study examined whether total enteral nutrition (TEN) and total parenteral nutrition (TPN) differentially modulates ghrelin, inflammatory mediator production, and cardiac dysfunction induced by LPS. Rats received isocaloric parenteral or enteral nutrition through implanted vascular catheters or gastrostomy tubes for 7 days. Enteral nutrition was provided in conventional (TEN-C) and immunonutrition (TEN-I) formulations. Subsequently, rats were injected i.v. with LPS. Serum ghrelin, TNF-alpha, and high mobility group box 1 levels were determined by enzyme-linked immunosorbent assay. Myocardiac function was also assessed via the Langendorff isolated heart technique. The TEN-C increased plasma ghrelin and inhibited inflammatory mediators both before and after LPS administration when compared with TPN or TEN-I. Furthermore, animals receiving TPN and TEN-I had significantly lower left ventricular developed pressure but increased pressure development during isovolumetric contraction (dP/dt(max)) and relaxation (dP/dt(min)) when compared with animals receiving TEN-C after LPS-induced shock (P < 0.05). We conclude that TEN-C more effectively increased plasma ghrelin levels than TPN and TEN-I. The maintenance of higher ghrelin levels in TEN-C rats was associated with inhibiting various inflammatory mediators and maintaining cardiac function during LPS-induced septic shock.     

Stimulation of adenosine A2A receptor inhibits LPS-induced expression of intercellular adhesion molecule 1 and production of TNF-alpha in human peripheral blood mononuclear cells

LPS stimulates CD14/Toll-like receptor (TLR) 4, leading to induce TNF-alpha production. Cell-to-cell interaction through the engagement between intercellular adhesion molecule (ICAM) 1 on monocytes and its ligand on T cells has been suggested to play a role in the TNF-alpha production by LPS-treated human peripheral blood mononuclear cells (PBMCs). Adenosine is reported to inhibit LPS-induced TNF-alpha production. However, little is known about the mechanism of the inhibitory effects induced by adenosine on the LPS-induced immune responses. We found that adenosine inhibited the expression of ICAM-1 and the production of TNF-alpha by human PBMC via adenosine A2A receptor in the presence of LPS. However, the stimulation of A1R or A3R enhanced the actions of adenosine. Adenosine had no effect on the expression of CD14 and TLR-4, suggesting that the inhibitory effects of adenosine on the LPS actions might be independent of the expression of CD14 and TLR-4. Thus, adenosine differentially regulates the expression of ICAM-1 and the production of TNF-alpha through plural subtypes of receptors.