Characterization of chronic idiopathic thrombocytopenic purpura in Japanese children: a retrospective multi-center study

The objectives of this study are to clarify (1) the difference in demographic and clinical variables at initial presentation between acute and chronic idiopathic thrombocytopenic purpura (ITP), and (2) the prognostic factors of patients with chronic ITP. We conducted a retrospective analysis of 247 children with newly diagnosed ITP between April 1991 and March 2006 who visited one of the 12 hospitals belonging to the Kyoto University Pediatric Hematologic Study Group. 180 and 67 cases were classified as the acute type and as the chronic type, respectively. Older age, higher initial platelet count, positive medical history or concomitant medical diagnosis, the absence of preceding infection or vaccination, and the absence of an increase in immunoglobulin were risk factors for the chronicity. The prognostic factors in chronic ITP were evaluated in 53 patients after excluding patients receiving splenectomy or having insufficient follow-up data. The overall time required for 50% resolution in patients with chronic ITP was approximately 5.6 years. Age at presentation of less than 3 years and higher platelet counts at the time of chronic ITP diagnosis were good prognostic factors. On the other hand, gender, initial platelet counts, and preceding infection or vaccination were not associated with the prognosis.     

Simplified dosing regimens of teicoplanin for patient groups stratified by renal function and weight using Monte Carlo simulation

The purpose of this study was (i) to determine the optimal dosage of teicoplanin for each patient group stratified by renal function and weight based on a population pharmacokinetic model and observed distribution of patient characteristics and (ii) to develop new simplified dosing regimens designed to achieve 15-30μg/mL. Patient data were collected retrospectively from routine therapeutic drug monitoring files of adult patients who were given the standard loading dose regimen of teicoplanin (400mg twice on Day 1, followed by 400mg once daily for 2 days) and whose trough concentration was measured just before administration on Day 4. Monte Carlo simulation was conducted to estimate the trough concentration at 72h after the initial loading dose (C(min)(72h)) and at steady state (C(ss)(min)). The percentage of observed C(min)(72h) in patients who received the standard loading dose regimen outside the non-parametric 90% prediction interval (from 5th to 95th percentile) of the simulated C(min)(72h) was <10%. Simplified loading dose and maintenance dose regimens for each group stratified by renal function and weight were created to achieve C(min)(72h) and C(ss)(min) of 15μg/mL and 20-25μg/mL, respectively. The percentage of C(min)(72h) and C(ss)(min) in the range 15-30μg/mL was 43-65% and 61-82% across each renal function and weight strata, respectively. These new simplified dosing regimens of teicoplanin could be helpful in individual adjustment of the loading and maintenance doses to achieve 15-30μg/mL.     

Irreversible optical clearing of sclera by dehydration and cross-linking

This study manipulates both clear cornea and opaque sclera by two dehydration processes for revealing the relationship between altered tissue structures and change in optical functions. In contrast to the high levels of light scattering in dehydrated tissues by critical point dry, a simple dehydration at 4-8 °C effectively and significantly improved their visible-light transmission, even in the sclera, with accompanying dense fiber packing. Further improvement in visible-light transmission, from 40-50% to 80-90%, has been achieved by flatting tissue surface with cover glasses during dehydration at low temperature. Such optical clearing of sclera by dehydration is reversible. However, chemical cross-linking effectively stabilizes their densely packed microscopic structures and visible-light transmission at over 50% irreversibly, even at wet conditions. Interestingly, the repetition of both low temperature dehydration/cross-linking treatments effectively reduced the required amounts of cross-linking reagents to keep a high transparency. Wet transparent cross-linked sclera can also show a characteristic strong tensile strength. Furthermore, rabbit corneal epithelium has regenerated on the transparent sclera with cross-linking in vitro.     

Transparent, tough collagen laminates prepared by oriented flow casting, multi-cyclic vitrification and chemical cross-linking

The lamellar architecture found in many natural fibrous tissues has a significant bearing on their specific functions. However, current engineered tissues have simultaneously no realistic structures and no adequate functions. This study demonstrates a two-step process for obtaining structurally mimicking laminates in natural fibrous tissues with good optical and mechanical characters from purified-clinically-safe collagen molecules. Stacked lamella structures can be created by repeating flow casting, with the controlling parallel/orthogonal directionalities of each thin single-layer (2-5 μm in thickness). The transparency of laminates is successfully improved by a unique multi-cyclic vitrification with chemical cross-linking. The directionalities of optical and mechanical functions in laminates are strongly related with the preferential collagen alignments in the laminates. The tensile strength of laminates is extremely higher than any other engineered materials as well as native cornea, which exhibit an orthogonal laminated collagen structure and a good optical transmission.     

Alexithymia and regional gray matter alterations in schizophrenia

Alexithymia is characterized by deficits in emotional self-awareness. Although alexithymia refers to a deficit in recognizing one's own emotions, some studies have focused on the relation between alexithymia and impaired social cognition. An association between alexithymia and schizophrenia has been previously reported, but the brain structures involved remain unclear. The present study investigated associations between alexithymia and specific brain structures to determine whether these regions overlapped with key structures underlying social cognition. Twenty-one patients with schizophrenia and 24 age-, gender- and education level-matched healthy controls underwent structural magnetic resonance imaging. Alexithymia was assessed using the 20-item Toronto Alexithymia Scale (TAS-20). We applied voxel-based morphometry to investigate the correlation between TAS-20 scores and regional brain alterations. TAS-20 scores were significantly higher in patients than controls. Bilateral ventral striatum and left ventral premotor cortex volumes were negatively correlated with TAS-20 total scores in controls, while left supramarginal gyrus (SMG) volume was negatively correlated with TAS-20 total scores in patients. These results suggest that schizophrenia is associated with alexithymia, and that gray matter alterations of the left SMG constitute a key pathology underlying alexithymia in schizophrenia. This association may be related to deficits in self-other distinction, self-disturbance, and language processing in schizophrenia.     

Size-dependent induction of accelerated blood clearance phenomenon by repeated injections of polymeric micelles

An accelerated blood clearance (ABC) phenomenon is induced by repeated injections of poly(ethylene glycol)-modified (PEGylated) liposomes. We previously indicated that the phenomenon was induced by polymeric micelles possessing PEG chains like as liposomes, although, the induction mechanism of the ABC phenomenon is not fully elucidated. In the present study, we investigate whether repeat-injection of the polymeric micelles having PEG chains trigger the phenomenon or not. Two polymeric micelles, PM-30 (polymeric micelles with 33.6nm in diameter) and PM-75 (76.2nm), were prepared with PEG-poly[Asp(pentyl)] and PEG-poly[Asp(nonyl)], respectively. We firstly examined the ABC-triggering effect of these micelles, and observed that both polymeric micelles, especially PM-75, induced the production of anti-PEG IgM antibody in treated mice. Then, PM-30 or PM-75 was preadministered into mice as a preconditioning. Seven days later, AlexaFluor594-labeled PM-30 or PM-75 was administered to determine the susceptibility of the phenomenon. As a result, rapid clearance of AlexaFluor594-labeled PM-75 from the bloodstream and accumulation in the liver were observed in PM-75 pretreated mice. Although, the ABC phenomenon of AlexaFluor594-labeled PM-30 was less obvious in PM-30 pretreated mice. Our present results indicated that the repeated injections of polymeric micelles caused the ABC phenomenon in a size-dependent manner.     

Imbalance Between Macrophage Migration Inhibitory Factor and Cortisol Induces Multiple Organ Dysfunction in Patients with Blunt Trauma

Migration inhibitory factor (MIF) is associated with multiple organ dysfunction syndrome (MODS) in patients with systemic inflammatory response syndrome (SIRS). Our purposes were to determine the serum MIF, cortisol, and tumor narcosis factor-α (TNF-α) and to investigate the influences of the balance between the levels of MIF and cortisol in patients with blunt trauma. The cortisol levels were identical between the patients with and without MODS. However, the MIF and TNF-α levels in the patients with MODS were statistically higher than those of the patients without MODS. The cortisol/MIF ratios in the patients with MODS were statistically higher than those of the patients without MODS. The results show that MIF and TNF-α play an important role together in posttraumatic inflammatory response. An excessive serum MIF elevation overrides the anti-inflammatory effects of cortisol and leads to persistent SIRS followed by MODS in blunt trauma patients.     

Tuberculous peritonitis during etanercept therapy for rheumatoid arthritis

In August 2010, a 73-year-old woman with rheumatoid arthritis receiving etanercept (ETN) therapy for two years, developed high-fever and abdominal fullness. Though she had not been exposed to tuberculosis, isoniazid prophylaxis was administrated. Antibiotics were not effective. CT images revealed the massive ascites and peritonitis, and Ga scintigraphy demonstrated notable uptake in the peritoneum. Ascites analysis showed an elevated adenosine deaminase activity value (104.9 IU/l) without malignant cells. Moreover, PCR and culture for Mycobacterium tuberculosis were positive. Finally, a diagnosis of tuberculous peritonitis was established. After initiating a standard anti-tuberculosis regimen with four drugs, her clinical condition ameliorated and ascites promptly regressed. Although the tuberculous peritonitis during ETN therapy is rare, this report emphasized the importance of initial suspicion of tuberculosis in these patients with tumor necrosis factor inhibitors such as ETN.     

Marked efficacy of metronidazole for the intestinal pseudoobstruction associated with systemic sclerosis

In May 2009, a 57-year-old woman who had rheumatoid arthritis since 9 years was admitted to our hospital for dyspnea due to interstitial pneumonia (IP). On admission, she exhibited proximal scleroderma, finger edema, Raynaud's phenomenon, digital pitting scars, ankyloglossia, and esophageal dysmotility. The patient was diagnosed as having systemic sclerosis (SSc), according to the American College of Rheumatology criteria. After initiation of high-dose corticosteroid therapy, gradual amelioration of IP was observed. However, the patient complained of abdominal fullness. Computed tomography and intestine series findings revealed significant dilatation of the small intestine due to intra-abdominal free air and pneumatosis cystoides intestinalis but no mechanical obstruction, leading to a diagnosis of SSc with pseudo-obstruction. The patient underwent decompression with a long intestinal tube, which led to improvement in her symptoms. Although erythromycin (EM) and some prokinetic agents were administered, abdominal involvement recurred several days after resumption of oral ingestion. Therefore, we changed the antibiotic from EM to metronidazole (750 mg/day). Her manifestations were promptly ameliorated by metronidazole therapy in 4 days and did not recur. Metronidazole is an antibiotic used to treat intra-abdominal anaerobic bacterial infections and is also commonly used in preoperative treatment for colorectal surgery. In conclusion, we report a case where SSc-associated pseudo-obstruction was successfully managed by metronidazole therapy.