Transforming growth factor-β1 mediated up-regulation of lysyl oxidase in the kidneys of hereditary nephrotic mouse with chronic renal fibrosis

Lysyl oxidase (LOX), an extracellular emzyme, plays a key role in the post-translational modification of collagens and elastin, catalyzing inter- and intra-crosslinking reactions. Because the crosslinked extracellular matrices (ECMs) are highly resistant to degradative enzymes, it is considered that the over-expression of LOX may cause severe fibrotic degeneration. In the present study, we addressed the role of LOX-mediated crosslinking in chronic renal tubulointerstitial fibrosis using an animal model of hereditary nephrotic syndrome, the Institute of Cancer Research (ICR)-derived glomerulonephritis (ICGN) mouse. Ribonuclease protection assay (RPA) revealed that LOX mRNA expression was up-regulated in the kidneys of ICGN mice as compared with control ICR mice. High-level expression of LOX and transforming growth factor (TGF)-β1 (an up-regulator of LOX) mRNA was detected in tubular epithelial cells of ICGN mouse kidneys by in situ hybridization. Type-I and -III collagens, major substrates for LOX, were accumulated in tubulointerstitium of ICGN mouse kidneys. The present findings imply that TGF-β1 up-regulates the production of LOX in tubular epithelial cells of ICGN mouse kidneys, and the excessive LOX acts on interstitial collagens and catalyzes crosslinking reactions. As a result, the highly crosslinked collagens induce an irreversible progression of chronic renal tubulointerstitial fibrosis in the kidneys of ICGN mice.     

Histopathological predictors of axillary lymph node metastases in patients with Breast Cancer

Background  A tumor 30 mm or less in diameter is a standard candidate for breast conserving surgery (BCS) in Japan. Axillary lymph node metastases (ALNM) is the most important prognostic factor for survival in patients with breast cancer, but the role of axillary node dissection has been controversial. Histopathological predictive factors of axillary lymph node involvement have not been established. The purpose of this study was to determine the association between the incidence of ALNM and histopathological factors by univariate and multivariate analysis. Methods  Sixty-five patients with noninvasive ductal carcinoma, and 993 patients with tumors 30 mm or less in diameter who underwent axillary dissection between 1988 and 1997 at our institute were reviewed. The association between ALNM and 13 histopathological factors (size, age, histological subtype, histological invasiveness, lymphatic invasion, vascular invasion, macroscopic classification, histological daughter mass, ductal spread, ER, PgR, p-53, and c-erbB-2) were analyzed by univariate and, when significant, by multivariate analysis. Results  Only one patient with noninvasive ductal carcinoma had ALNM, and 33.1% of 993 patients with a tumor 30 mm or less in size had ALNM. Multivariate analysis identified six factors as independent predictors for ALNM: lymphatic invasion, size, histological invasiveness, macroscopic classification, age and histological daughter mass. Conclusions  Axillary lymph node dissection can be omitted in patients with noninvasive ductal carcinoma. Histopathological features of tumors 30 mm or less in diameter can be used to estimate the risk of ALNM, and routine axillary node dissection might be spared in selected patients at minimal risk of ALNM, if the treatment decision is not influenced by lymph node status, such as in elderly patients.     

Dystrophin基因内部四个STR位点多态性与DMD基因携带者检出

应用PCR技术分别体外扩增dystraphin基因内部四个STR位点的(CA)n重复序列,聚丙烯酰胺凝胶电泳、硝酸银染色检测扩增产物,分析STR位点的多态性,所得STR-44、STR-45、STR-49和STR-50各位点的多态信息量分别为0.864、0.892、0.906和0.713。并利用这些位点多态性连锁分析检测5个DMD家系中8名女性亲属,检出其中6名为DMA基因携带者。为非缺失型DMD/BMD基因诊断及其家系中携带者检出提供有效手段     

Pathophysiology of chronic daily headache

Despite no clear explanation of the mechanism underlying chronic daily headache, sensitization of central nociceptive neurons is one possibility. Either prolonged activation of peripheral nociceptors or any factors that can alter the endogenous pain control system can trigger this process. A decrease in platelet serotonin has been observed in patients with chronic tension-type headache as well as migraine patients with medication-induced headache. It was also shown that chronic analgesic exposure led to changes in the serotonin content and the density of the 5-HT_2A receptor in the cerebral cortex. The plasticity of the serotonin-dependent pain control system may facilitate the process of sensitization and results in the development of chronic daily headache.     

Involvement of Pro‐Nociceptive 5‐HT2A Receptor in the Pathogenesis of Medication‐Overuse Headache

(Headache 2010;50:185‐197) Objectives.— To determine the involvement of 5‐HT_2A (5‐HT_2A) receptor in the process of trigeminal plasticity induced by chronic analgesic exposure and in the process of inflammatory‐induced thermal hyperalgesia. Background.— Derangement in 5‐HT_2A serotonin receptor has been reported to implicate in pathogenesis of medication‐overuse headache. No clear explanation concerning the precise roles of these receptors in the process. Methods.— Wistar rats were daily administered with paracetamol (200 mg/kg) for 30 days. On the next day, ketanserin, a 5‐HT_2A antagonist, or saline was given prior to cortical spreading depression (CSD) induction. Electrocorticogram, cortical blood flow, Fos and 5‐HT_2A‐immunoreactivity in cortex and trigeminal pathway were studied. In the other experiment, complete Freund's adjuvant was injected into the rat hind paw to induce tissue inflammation. Three days later, ketanserin was given and noxious heat was applied to both inflamed and noninflamed paws. The response between 2 sides was compared by measuring paw withdrawal latency. Results.— Chronic paracetamol exposure led to an increase in CSD frequency and CSD‐evoked Fos expression in cerebral cortex indicating the increase in neuronal excitability. Prolonged medication exposure also facilitated trigeminal nociception as evident by an increase in CSD‐evoked Fos expression in trigeminal nucleus caudalis. The expression of 5‐HT_2A receptor in cerebral cortex and trigeminal ganglia was enhanced by chronic paracetamol administration. Pretreatment with ketanserin significantly attenuated these effects. The second experiment showed that ketanserin was able to lengthen the paw withdrawal latency in the inflamed side but did not alter nociceptive response in the noninflamed side. Conclusion.— These findings suggest that up‐regulation of pro‐nociceptive 5‐HT_2A receptor is an important step in the process of cortical hyper‐excitation and nociceptive facilitation induced by chronic analgesic exposure.     

High Rate of Reduced Susceptibility to Ciprofloxacin and Ceftriaxone among Nontyphoid Salmonella Clinical Isolates in Asia

This multinational study from Asia revealed that reduced susceptibility to ciprofloxacin (MIC, 0.125 to 1 μg/ml) in nontyphoid Salmonella isolates was common in Taiwan (48.1%) and Thailand (46.2%) and in S. enterica serotype Choleraesuis (68.8%) and S. Virchow (75.0%) from all countries. Reduced susceptibility to ceftriaxone (MIC, 2 to 8 μg/ml) remained uncommon in Asia, except in Taiwan (38.0%) or in S. Typhimurium (25.0%) from all countries.Nontyphoid Salmonella bacteria, with more than 2,500 serotypes, usually cause diarrheal diseases in humans that may be complicated by extraintestinal infections, such as bacteremia, meningitis, and osteomyelitis (11). Resistance to antimicrobial agents, including fluoroquinolones and expanded-spectrum cephalosporins, has been a serious problem worldwide. Nontyphoid salmonellosis has been rampant in Asia (7); however, data on the antimicrobial susceptibilities, as well as the prevalence, of various serotypes in many Asian countries after 2000 have been lacking.During 2003 to 2005, 400 clinical isolates of nontyphoid Salmonella bacteria were randomly collected from 11 medical centers in seven Asian countries (Table ​(Table1)1) and transported to the central laboratory in Samsung Medical Center, Seoul, Korea, for serogrouping and serotyping using O and H antisera, respectively (Difco Laboratories, Detroit, MI). Susceptibilities to ciprofloxacin, tetracycline, ceftriaxone, ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole were determined by a broth microdilution method, and the results were interpreted according to the breakpoints for MICs suggested by the NCCLS (10). For statistical analysis, isolates in the “intermediate” category were deemed “resistant” in this study. Concomitant resistance to at least three of the six antibiotics tested was defined as multidrug resistance (MDR). Isolates with ciprofloxacin MICs of 0.125 to 1 μg/ml were defined as having “reduced susceptibility” to ciprofloxacin (9). Similarly, “reduced susceptibility” to ceftriaxone was defined as isolates showing ceftriaxone MICs of 2 to 8 μg/ml (14). These definitions were proposed in previous reports to reflect the clinical therapeutic responses (9, 14). The χ² test and Student''s t test were used to determine the significance of differences, and a P value of <0.05 was considered statistically significant.

TABLE 1.

Serotype distribution of the 400 nontyphoid Salmonella isolates among the countries

Construction of a Recombinant Porcine Epidemic Diarrhea Virus Encoding Nanoluciferase for High-Throughput Screening of Natural Antiviral Products

Porcine epidemic diarrhea virus (PEDV) is the predominant cause of an acute, highly contagious enteric disease in neonatal piglets. There are currently no approved drugs against PEDV infection. Here, we report the development of a nanoluciferase (NLuc)-based high-throughput screening (HTS) platform to identify novel anti-PEDV compounds. We constructed a full-length cDNA clone for a cell-adapted PEDV strain YN150. Using reverse genetics, we replaced the open reading frame 3 (ORF3) in the viral genome with an NLuc gene to engineer a recombinant PEDV expressing NLuc (rPEDV-NLuc). rPEDV-NLuc produced similar plaque morphology and showed similar growth kinetics compared with the wild-type PEDV in vitro. Remarkably, the level of luciferase activity could be stably detected in rPEDV-NLuc-infected cells and exhibited a strong positive correlation with the viral titers. Given that NLuc expression represents a direct readout of PEDV replication, anti-PEDV compounds could be easily identified by quantifying the NLuc activity. Using this platform, we screened for the anti-PEDV compounds from a library of 803 natural products and identified 25 compounds that could significantly inhibit PEDV replication. Interestingly, 7 of the 25 identified compounds were natural antioxidants, including Betulonic acid, Ursonic acid, esculetin, lithocholic acid, nordihydroguaiaretic acid, caffeic acid phenethyl ester, and grape seed extract. As expected, all of the antioxidants could potently reduce PEDV-induced oxygen species production, which, in turn, inhibit PEDV replication in a dose-dependent manner. Collectively, our findings provide a powerful platform for the rapid screening of promising therapeutic compounds against PEDV infection.     

Treatment of infantile spasms in Saudi Arabia

Objectives:To evaluate the treatment approach and compliance of pediatric neurologists with evidence-based guidelines across Kingdom of Saudi Arabia (KSA). These guidelines that clarify the optimal management of infantile spasms (IS) are not widely followed for various practical reasons.Methods:Physicians practicing in the field of pediatric neurology in KSA were contacted from the database of national societies. A cross-sectional study was conducted using a structured 20-item on-line survey designed to examine their clinical experience with IS and their treatment choices.Results:A total of 52 pediatric neurologists completed the survey (69% estimated capture rate). They received their formal training within KSA (40%), North America (33%), or Europe (14%). The majority practiced in 2 major cities, Riyadh (46%) or Jeddah (19%). Vigabatrin was favored over adrenocorticotropic hormone (ACTH) as first line drug for patients without tuberous sclerosis complex (48% vs. 21%). Several factors correlated with correctly selecting ACTH as first line including western training (33% vs. 5%, p=0.001), practicing in the city of Riyadh (25% vs. 14%, p=0.001), or having >10 years of clinical experience (25% vs. 5%, p=0.017). Reasons for not complying with the recommended treatment guidelines included lack of availability of ACTH (42%), side effect profile of steroids (29%), and personal preferences (14%). Only 4% admitted lack of awareness of the currently published management guidelines.Conclusion:Many pediatric neurologists in KSA are not following the published IS management guidelines. Using ACTH as first line correlated with their training, practice location, and years of experience. Lack of drug availability and side effect profile were common reasons for not complying with the management guidelines.

Infantile spasms (IS) represent a severe epilepsy syndrome that require prompt diagnosis and treatment.1 Such early management could favorably influence the ultimate seizure control and long-term developmental outcome.2 The majority of infants (70%) are grouped into a symptomatic group with an identifiable underlying etiology, most importantly tuberous sclerosis complex.1,2 In addition to identifying such etiologies and early treatment, factors that can influence the prognosis include the utilized treatment protocols.3 Steroids, specifically adrenocorticotropic hormone (ACTH) and oral prednisone, were found to be the most effective initial treatment, excluding patients with tuberous sclerosis complex where Vigabtrin (VGB) was found to be the preferred initial drug.4 Other available drugs include, topiramate, levetiracetam, valproic acid, benzodiazepines, lamotrigine, sulthiame, pyridoxine (in selected patients), and zonisamide, all can be used with variable success. Non-pharmacological treatments should also be considered in selected resistant cases and include the ketogenic diet, intravenous immunoglobulin (IVIG), and epilepsy surgery.4 Evidence-based guidelines regarding the optimal management of IS that have been published are mostly based on personal preference and individual expert opinions rather than clear clinical evidence.5 Therefore, the approaches to IS treatment remain influenced by a myriad of factors, including the availability of medications, side effects profiles, cost, personal preferences, and experiences of the treating physicians. In this study, we aim to evaluate the treatment approaches across Kingdom of Saudi Arabia (KSA) and examine the compliance of pediatric neurologists with the current IS management guidelines and the obstacles to its application.