STAT3 regulates SRGN and promotes metastasis of nasopharyngeal carcinoma through the FoxO1-miR-148a-5p-CREB1 axis

Nasopharyngeal carcinoma (NPC), which is marked by a distinct distribution, is a common subtype of epithelial carcinoma arising from the nasopharyngeal mucosal lining. SRGN acts as an important and poor prognostic factor of NPC through multiple different mechanisms. However, the biological role and mechanism of SRGN in NPC remain unknown. Expression levels of miR-148a-5p, CREB1, FoxO1, and SRGN in NPC tissues and cell lines were tested by qRT-PCR or/and Western blot. The impacts of miR-148a-5p, CREB1, FoxO1, and SRGN on NPC cell viability, proliferation, migration, and invasion were estimated in vitro by CCK-8, colony formation, wound healing and Transwell experiments, and in vivo by a xenograft tumor model. JASPAR analysis was used to predict the binding activity of Foxo1 (CREB1) with the miR-148a-5p (SRGN) promoter, and the interaction was validated by EMSA and ChIP assays. The miR-148a-5p-CREB1 interaction was validated by a dual-luciferase reporter and RIP assays. CREB1 and SRGN were increased while miR-148a-5p was decreased in NPC. Silencing of SRGN and CREB1, as well as miR-148a-5p overexpression, repressed NPC tumor progression in vitro and in vivo. CREB1 promoted SRGN expression in NPC by targeting the promoter area of SRGN. Silencing of FoxO1 facilitated NPC tumor progression, while silencing of STAT3 repressed NPC tumor progression. FoxO1 bound to and regulated miR-148a-5p in NPC, and miR-148a-5p targeted CREB1. Additionally, FoxO1 knockdown abolished the downregulation of CREB1 and SRGN induced by STAT3 silencing. Our results suggest that STAT3 regulates SRGN and promotes the growth and metastasis of NPC through the FoxO1-miR-148a-5p-CREB1 axis.

Prognostic value of hypothyroidism in patients undergoing intensity-modulated radiation therapy for nasopharyngeal carcinoma

BACKGROUND

The purpose of this study was to investigate the effect of hypothyroidism and thyroxine replacement therapy on the prognosis of nasopharyngeal carcinoma (NPC) patients.

METHODS

The clinical data of 284 NPC patients, who received intensity-modulated radiation therapy (IMRT) between January 2011 and December 2016, were retrospectively analyzed.

RESULTS

Hypothyroidism occurred in 38% of patients. Patients with hypothyroidism had significantly better disease-free survival (DFS) (p = 0.002) and relapse-free survival (RFS) (p = 0.008). Multivariate analysis showed that hypothyroidism was a positive independent prognostic factor (DFS and RFS). Among the patients with hypothyroidism, thyroxine replacement therapy did not yield inferior survival (DFS, RFS, all p > 0.05).

CONCLUSIONS

The NPC patients with complete response are at risk of hypothyroidism, which is attributable to escalating dose. These patients experienced clinical hypothyroidism could be adequately treated with thyroid hormone replacement. Further investigation of the underlying biological mechanism and potential therapeutic implications are required.

Effects of Surgery Combined with Chemoradiotherapy on Short- and Long-Term Outcomes of Early-Stage Nasopharyngeal Carcinoma

Objective

The efficacy of surgery as the primary treatment modality for nasopharyngeal carcinoma (NPC) is yet to be clarified. Therefore, we aimed to explore the short- and long-term efficacy of surgery for early-stage NPC.

Methods

We retrospectively evaluated 341 patients diagnosed with early-stage NPC between September 2010 and December 2015. Among them, 58 patients underwent endoscopic nasopharyngectomy combined with chemoradiotherapy, whereas 283 patients underwent conventional chemoradiotherapy. The patients who underwent concurrent chemoradiotherapy or radiotherapy alone were matched to patients who underwent surgery in a 1:2 ratio using propensity score matching to analyze the clinical efficacy of each therapeutic modality. The primary endpoint was survival, and the secondary endpoints were tumor regression rate and reduction in Epstein–Barr virus (EBV)-DNA levels.

Results

After matching, 156 patients were enrolled (58 patients in the surgery group; 98 patients in the non-surgery group). The baseline data of the matched patients had good inter-group comparability (All P>0.05). The surgery group had significantly higher 5-year overall survival (98.30% vs. 91.70%), disease-free survival (98.30% vs. 81.40%), and recurrence-free survival (100.00% vs. 90.10%) rates than did the non-surgery group (All P<0.05). In total, 0 and 14 patients in the surgery and non-surgery groups, respectively, had residual cancer at the end of treatment (P=0.001). All patients in the surgery group tested negative for EBV-DNA, whereas two patients in the non-surgery group tested positive. The incidence of hematologic toxicity during treatment was similar between the two groups (All P>0.05). Still, the incidence of severe oral mucositis was lower in the surgery group than in the non-surgery group (37.9% vs. 54.08%, P=0.051).

Conclusion

Surgery can improve the clearance rate of EB virus and reduce tumor residue. Surgery may be a safe and effective treatment for early NPC.

Effects of hepatitis B virus infection and antiviral therapy on the clinical prognosis of nasopharyngeal carcinoma

Purpose

To investigate the clinical characteristics of nasopharyngeal carcinoma (NPC) and a concomitant hepatitis B virus (HBV) infection, as well as the potential effects of HBV infection and antiviral therapy on prognosis.

Methods

We conducted a retrospective chart review of all NPC patients from December 2010 to December 2014. After collecting medical records and conducting follow‐ups on patients, a total of 876 eligible NPC patients were included. For each patient, medical records were reviewed. Factors predictive of outcome were compared using the log‐rank test and Cox regression analysis.

Results

Among the 876 participants, 106 (12.1%) patients were HBV‐infected patients. The hepatitis B surface antigen‐positive [HBsAg(+)] group had a lower CD⁴⁺ T cell count than the HBsAg(−) group (P = .048). Among patients with stage I/II NPC, 5‐year overall survival (OS), disease‐free survival (DFS), relapse‐free survival, and distant metastasis‐free survival (DMFS) of the HBsAg(+) group were 82.5%, 70.7%, 87.7%, and 76.6%, respectively, whereas those of the HBsAg(−) group were 91.4%, 86.0%, 93.8%, and 92.1%, respectively. Statistically significant differences in OS, DFS, and DMFS existed between both groups (P = .017, .018, and .004, respectively). The multivariate analysis indicated that HBsAg status and N stage are independent risk factors affecting OS, DFS, and DMFS of NPC patients. A statistically significant difference in 5‐year DMFS existed between the antivirus (90.0%) and no‐antivirus groups (70.0%) (P = .043).

Conclusions

Hepatitis B virus infection is an independent risk factor for early stage NPC, which may be associated with its reduced immune functions compared to the HBsAg(−) group. Anti‐HBV treatment may improve the prognosis of HBV‐infected NPC patients.

Realizing Magnetoelectric Coupling with Hydrogen Intercalation

Materials with a coexistence of magnetic and ferroelectric order (i.e., multiferroics) provide an efficient route for the control of magnetism by electric fields. Unfortunately, a long-sought room temperature multiferroic with strongly coupled ferroelectric and ferromagnetic (or ferrimagnetic) orderings is still lacking. Here, we propose that hydrogen intercalation in antiferromagnetic transition-metal oxides is a promising way to realize multiferroics with strong magnetoelectric coupling. Taking brownmillerite SrCoO_{2.5} as an example, we show that hydrogen intercalated SrCoO_{2.5} displays strong ferrimagnetism and large electric polarization in which the hydroxide acts as a new knob to simultaneously control the magnetization and polarization at room temperature. We expect that ion intercalation will become a general way to design magnetoelectric and spintronic functional materials.

[Risk factors and sonographic findings associated with the type of placenta accreta spectrum disorders]

Objective: To evaluate the risk factors and sonographic findings of pregnancies complicated by placenta increta or placenta percreta. Methods: Totally, 2 219 cases were retrospectively analyzed from 20 tertiary hospitals in China from January 2011 to December 2015. The data were collected based on the original case records. All cases were divided into two groups, the placenta increta (PI) group (79.1%, 1 755/2 219) and the placenta percreta (PP) group (20.9%, 464/2 219) , according to the degree of placental implantation. The risk factors and sonographic findings of placenta increta or percreta were analyzed by uni-factor and logistic regression statistic methods. Results: The risk factors associated with the degree of placental implantation were age, gravida, previous abortion or miscarriage, previous cesarean sections, and placenta previa (all P<0.05), especially, previous cesarean sections (χ(2)=157.961) and placenta previa (χ(2)=91.759). Sonographic findings could be used to predict the degree of placental invasion especially the boundaries between placenta and uterine serosa, the boundary between placenta and myometrium, the disruption of the placental-uterine wall interface and loss of the normal retroplacental hypoechoic zone(all P<0.01). Conclusions: Previous cesarean sections and placenta previa are the main independent risk factors associated with the degree of placenta implantation. Ultrasound could be used to make a prenatal suggestive diagnosis of placenta accreta spectrum disorders.

Association of NUDT15 c.415C>T allele and thiopurine-induced leukocytopenia in Asians: a systematic review and meta-analysis

BACKGROUND

Thiopurines, commonly used to treat autoimmune conditions and cancer, can be limited by life-threatening leucopenia. However, whether NUDT15 (nucleoside diphosphate-linked moiety X-type motif 15) is associated with thiopurine-induced leucopenia in Asians is controversial.

METHODS

Relevant studies in English that were published until July 10, 2016 were identified through PubMed, EMbase, and other web knowledge databases. Study quality was assessed according to the Newcastle-Ottawa Scale (NOS) criteria. Summary risk ratio (RR) and 95% confidence intervals (CI) were estimated based on a fixed-effects model or a random-effects model, depending on the absence or presence of significant heterogeneity.

RESULTS

Seven studies of 1138 patients met our inclusion criteria. Random-effects model meta-analysis provided evidence that T carriers of NUDT15 c.415C>T were significantly correlated with high incidences of thiopurine-induced leukocytopenia [CT + TT vs. CC: RR = 3.79, 95%CI (2.64 ~ 5.44), P < 0.00001]. This correlation was especially strong in TT patients, where it was found to be significantly increased by 6.54-fold compared with CC patients [TT vs. CC: RR = 6.54, 95%CI (3.34 ~ 12.82), P < 0.00001]. We also found that the NUDT15 c.415C>T variant was common in Asians and Hispanics, but rare in Europeans and Africans; the frequency of the NUDT15 c.415C>T distribution varied substantially by race/ethnicity.

CONCLUSION

The results of this meta-analysis confirm that NUDT15 c.415C>T may be an important predictor of thiopurine-induced leukocytopenia in Asians. Genotype targeting of NUDT15 c.415C>T before initiating thiopurine treatment may be useful to limit leukocytopenia.

[Application of cut needle biopsy in the diagnosis of submucosal type of nasopharyngeal neoplasms]

Objective: To evaluate the efficacy of cut needle biopsy in the diagnosis of submucosal nasopharyngeal neoplasms. Methods: Cut needle biopsy performed with automatic biopsy gun was applied in 17 cases with submucosal type of nasopharyngeal neoplasms.The bleeding quantity was recorded and the pain was measured by score. Results: Adequate biopsy sample for hispathological diagnosis was received from each of the 17 patients. And the hispathological diagnosis were consistent with the follow-up visit. The bleeding quantity ranged from 1 to 5 ml ((1.9±0.3)ml). The scores of numerical rating scale were between 2-7 (4.0±0.4). There were no serious complications such as hemorrhea. There were 3 patients of inflammation in pathological diagnosis. And These 3 patients had no tumor during the follow-up( from 6 to 33 months). There were 12 patients of undifferentiated cancer. Among the 12 patients, there were five newly diagnosed patients and seven recurrent patients. There were 2 patients of lymphoma. Conclusion: Cut needle biopsy has the advantages of minimal trauma, shorter operative time, less bleeding, light pain, and no serious complications. It is simple, safe, and worth of application clinically.

Associations of depression with impaired glucose regulation, newly diagnosed diabetes and previously diagnosed diabetes in Chinese adults

AIM

To examine the association between depression and impaired glucose regulation, newly diagnosed diabetes and previously diagnosed diabetes in middle-aged and elderly Chinese people, and whether depression was associated with different treatment regimens or durations of diabetes.

METHODS

A cross-sectional study was performed among 229,047 adults living in the community aged ≥ 40 years from 25 centres in China. The self-reported depression rating scale Patient Health Questionnaire 9 (PHQ-9) was used to diagnose probable and sub-threshold depression. Glucose metabolism status was determined according to World Health Organization 1999 diagnostic criteria.

RESULTS

The numbers of participants with normal glucose regulation, impaired glucose regulation, newly diagnosed diabetes and previously diagnosed diabetes were 120,458, 59,512, 24,826 and 24,251, respectively. The prevalence of sub-threshold depression in the total sample of participants was 4.8% (4.8%, 4.8%, 4.4% and 5.6% from normal glucose regulation to previously diagnosed diabetes, respectively), and the prevalence of probable depression was 1.1% (1.1%, 1.0%, 0.9% and 1.8% from normal glucose regulation to previously diagnosed diabetes, respectively). Compared with participants with normal glucose regulation, those with previously diagnosed diabetes had increased odds of probable depression [odds ratio (OR) = 1.61, 95% confidence interval (CI) 1.39-1.87] and sub-threshold depression (OR = 1.14, 95% CI 1.06-1.24), after adjustment for multiple confounding factors. Newly diagnosed diabetes or impaired glucose regulation was not associated with depression. Among those with previously diagnosed diabetes, insulin treatment was associated with greater odds of depression compared with no treatment or oral anti-diabetic medicine.

CONCLUSION

Previously diagnosed diabetes, but not newly diagnosed diabetes or impaired glucose regulation, was associated with a higher prevalence of depression. Patients receiving insulin were more likely to have depression than those not receiving treatment or being treated with oral anti-diabetic medicine.

Predicting thermophilic proteins with pseudo amino acid composition:approached from chaos game representation and principal component analysis

Comprehensive knowledge of thermophilic mechanisms about some organisms whose optimum growth temperature (OGT) ranges from 50 to 80 °C degree plays a major role for helping to design stable proteins. How to predict function-unknown proteins to be thermophilic is a long but not fairly resolved problem. Chaos game representation (CGR) can investigate hidden patterns in protein sequences, and also can visually reveal their previously unknown structures. In this paper, using the general form of pseudo amino acid composition to represent protein samples, we proposed a novel method for presenting protein sequence to a CGR picture using CGR algorithm. A 24-dimensional vector extracted from these CGR segments and the first two PCA features are used to classify thermophilic and mesophilic proteins by Support Vector Machine (SVM). Our method is evaluated by the jackknife test. For the 24-dimensional vector, the accuracy is 0.8792 and Matthews Correlation Coefficient (MCC) is 0.7587. The 26-dimensional vector by hybridizing with PCA components performs highly satisfaction, in which the accuracy achieves 0.9944 and MCC achieves 0.9888. The results show the effectiveness of the new hybrid method.

A new hybrid fractal algorithm for predicting thermophilic nucleotide sequences

Knowledge of thermophilic mechanisms about some organisms whose optimum growth temperature (OGT) ranges from 50 to 80 degree plays a major role in helping design stable proteins. How to predict a DNA sequence to be thermophilic is a long but not fairly resolved problem. Chaos game representation (CGR) can investigate the patterns hiding in DNA sequences, and can visually reveal previously unknown structure. Fractal dimensions are good tools to measure sizes of complex, highly irregular geometric objects. In this paper, we convert every DNA sequence into a high dimensional vector by CGR algorithm and fractal dimension, and then predict the DNA sequence thermostability by these fractal features and support vector machine (SVM). We have conducted experiments on three groups: 17-dimensional vector, 65-dimensional vector, and 257-dimensional vector. Each group is evaluated by the 10-fold cross-validation test. For the results, the group of 257-dimensional vector gets the best results: the average accuracy is 0.9456 and average MCC is 0.8878. The results are also compared with the previous work with single CGR features. The comparison shows the high effectiveness of the new hybrid fractal algorithm.

[Choice of surgical approaches for salvage surgery of primary lesion recurrence and residual cases of nasopharyngeal carcinoma]

OBJECTIVE

The choice of surgical approaches for salvage surgery based on the location and invasion of recurrent and residual lesions of nasopharyngeal carcinoma (NPC), surgical results, complications, and survival were assessed.

METHODS

Thirty-seven cases with recurrent and residual lesions of NPC underwent salvage surgery between March 1991 and January 2005 were analysed retrospectively. Of 37 patients, 23 were men and 14 women, with a median age of 46.5 years (26 - 57 years); 4 were at stage I, 10 at stage II, 14 at stage III, and 9 at stage IV; 5 cases were with cervical metastasis, including 3 cases of N1 and 2 cases N2. All recurrent and residual lesions of NPC were determined by biopsy. On the location and invasion of recurrent and residual lesions of NPC, 8 cases underwent endoscopic resection of lesions, 12 cases of the palate nasopharyngectomy, 5 cases of maxillary swing, 4 cases of maxillary swing plus prerenal approach, 2 cases of lateral rhinotomy plus coronal flap approach, and 6 cases transfacial plus nasal pyramid swing approach. Five cases with cervical metastasis received neck dissection in addition to the operations for recurrent and residual lesions of NPC. Postoperatively 31 cases received radiotherapy with dosage of 60 Gy, among them 15 cases with concurrent chemoradiation therapy, and 6 cases with clear surgical margin did not received radiotherapy or chemotherapy. The cases were followed up for 12 - 72 months, with a median of 45 months.

RESULTS

Total resection for the recurrent and residual lesions of NPC accounted for 91.8% (34/37) and subtotal resection for 8.2% (3/37). The accident of perioperative complications was 24.3% (9/37). The 3- and 5-year overall disease-free survival rates (DFSR) were 62.1% and 43.3%, respectively. The 3- and 5-year overall survival rates (OSR) were 72.9% and 51.3%, respectively. The 5 year DFSR of cases at stage I-IV were 100%, 40%, 28% and 11% (χ(2) = 10.0, P < 0.01), respectively. The 5 year OSR were 100%, 70%, 35% and 28% (χ(2) = 11.5, P < 0.01), respectively.

CONCLUSIONS

Salvage surgery is a justified treatment for the recurrent and residual lesions of NPC, by which some patients with recurrent and residual lesions of NPC can be salvaged.

Using tea stalk lignocellulose as an adsorbent for separating decaffeinated tea catechins

Lignocelluloses prepared from woody tea stalk, pine sawdust and sugarcane bagasse were used as adsorbents to isolate decaffeinated catechins from tea extracts and compared with synthetic macroporous resin HPD 600. HPD 600 had the highest adsorption capacity to catechins, followed by tea stalk lignocellulose while lignocelluloses of pine sawdust and bagasse the least. Tea stalk lignocellulose absorbed preferentially tea catechins and showed a good selectivity. HPD 600 absorbed caffeine and tea catechins simultaneously. The kinetics data of tea stalk lignocellulose showed a good fit with the Langmuir isotherm model. It is considered that tea stalk lignocellulose is an alternative low-cost adsorbent for preparing decaffeinated tea catechins.

Selective analysis of molecular states by functionalized scanning tunneling microscopy tips

Selective analysis of molecular states in scanning tunneling microscopy (STM) has so far been achieved in a few cases by tuning the bias range of the STM in high-resolution measurements. Correspondingly, perylene adsorbed in a close-packed monolayer on Ag(110) is imaged mainly through the pi states of the molecule. By contrast, functionalizing the STM tip with a perylene molecule leads to a mismatch between the energy levels of the STM tip and the molecule adsorbates and, instead, images only the metal states of the underlying silver surface. The observation opens a route for better energy selectivity in electron transport measurements through organic interfaces.

Reduction in psychopathology following bariatric surgery for morbid obesity

BACKGROUND

Although there has been some disagreement, there is growing evidence now that psychopathology is a comorbidity of morbid obesity among patients seeking bariatric surgery. The aim of this study was to determine whether psychopathology decreases following this surgery.

METHODS

Utilizing a national sample, this study focused on pre- and post-surgery scores on the Minnesota Multiphasic Personality Inventory, Second Edition (MMPI-2). The MMPI-2 was administered first during the pre-surgery medical examination, and again between 6 months and 1 year following surgery.

RESULTS

Validity scale scores on the pre- and post-surgery MMPI-2s indicated that there was no impediment to interpreting the clinical scale scores of these tests. There was a pervasive pattern of statistically significant decreases in pre- to post-surgery clinical scale scores. Further, comparison of MMPI-2 clinical scale scores to available test norms showed that the number of participants showing signs of mental disorders was unusually high before surgery, and at or below the test norms following surgery.

CONCLUSIONS

There is clear evidence in this study that psychopathology declines following bariatric surgery. The unusually high levels of psychopathology before surgery may be a joint function of the factors producing the morbid obesity, and a reaction to the obesity itself. That psychopathology declines following surgery to levels expected in the general population indicates that the patients were becoming more positive about their lives.

Toxoplasma gondii infection: relationship between seroprevalence and risk factors among inhabitants in two offshore islands from Taiwan

A seroepidemiological study of toxoplasmosis among inhabitants of Penghu Island and Kinmen Island offshore of Taiwan was performed using the latex agglutination test from July 1999 to June 2000. In order to determine risk factors for Toxoplasma gondii (T. gondii) infection, the effects of a history of eating raw/undercooked meats and raising pets were focused on using a self-administrated questionnaire. The seroprevalence (28.2%; 190/673) in Kinmen Island was significantly higher than that (2.71%; 8/293) in Penghu Island (P < 0.001). A significant difference in seroprevalence between both sexes was found in Kinmen Island (P < 0.05), but not in Penghu Island. The results of multiple logistic regression analysis showed that the older the age, the higher the OR in both Islands, yet a significant difference in seroprevalence between children and adults or the elderly was observed in Kinmen Island (P < 0.001). Moreover, those who had histories of raising cats or eating raw/undercooked meats seemed to have greater opportunities to become infected with T. gondii (OR = 2.9, 95% CI = 1.9-4.5, P < 0.001; OR = 1.5, 95% CI = 1.1-2.1, P < 0.05). In Penghu Island, a significant association between seroprevalence and a history of raising cats was also observed (OR = 4.6, 95% CI = 1.1-20.1, P < 0.05). Furthermore, workers, farmers, and fishermen seemed to be more susceptible to T. gondii infection than students in Kinmen Island.

The cyclization of farnesyl diphosphate and nerolidyl diphosphate by a purified recombinant delta-cadinene synthase

The first step in the conversion of the isoprenoid intermediate, farnesyl diphosphate (FDP), to sesquiterpene phytoalexins in cotton (Gossypium barbadense) plants is catalyzed by delta-cadinene (CDN) synthase. CDN is the precursor of desoxyhemigossypol and hemigossypol defense sesquiterpenes. In this paper we have studied the mechanism for the cyclization of FDP and the putative intermediate, nerolidyl diphosphate, to CDN. A purified recombinant CDN synthase (CDN1-C1) expressed in Escherichia coli from CDN1-C1 cDNA isolated from Gossypium arboreum cyclizes (1RS)-[1-2H](E, E)-FDP to >98% [5-2H]and [11-2H]CDN. Enzyme reaction mixtures cyclize (3RS)-[4,4,13,13,13-2H5]-nerolidyl diphosphate to 62.1% [8,8,15,15,15-2H5]-CDN, 15.8% [6,6,15,15,15-2H5]-alpha-bisabolol, 8.1% [6,6,15,15,15-2H5]-(beta)-bisabolene, 9.8% [4,4,13,13-2H4]-(E)-beta-farnesene, and 4.2% unknowns. Competitive studies show that (3R)-nerolidyl diphosphate is the active enantiomer of (3RS)-nerolidyl diphosphate that cyclized to CDN. The kcat/Km values demonstrate that the synthase uses (E,E)-FDP as effectively as (3R)-nerolidyl diphosphate in the formation of CDN. Cyclization studies with (3R)-nerolidyl diphosphate show that the formation of CDN, (E)-beta-farnesene, and beta-bisabolene are enzyme dependent, but the formation of alpha-bisabolol in the reaction mixtures was a Mg2+-dependent solvolysis of nerolidyl diphosphate. Enzyme mechanisms are proposed for the formation of CDN from (E,E)-FDP and for the formation of CDN, (E)-beta-farnesene, and beta-bisabolene from (3RS)-nerolidyl diphosphate. The primary structures of cotton CDN synthase and tobacco epi-aristolochene synthase show 48% identity, suggesting similar three-dimensional structures. We used the SWISS-MODEL to test this. The two enzymes have the same overall structure consisting of two alpha-helical domains and epi-aristolochene synthase is a good model for the structure of CDN synthase. Several amino acids in the primary structures of both synthases superimpose. The amino acids having catalytic roles in epi-aristochene synthase are substituted in the CDN synthase and may be related to differences in catalytic properties.

Physiologic-pathologic correlation in Guillain-Barré syndrome in children

OBJECTIVE

To correlate electrophysiologic patterns with sural nerve pathology in children with Guillain-Barré syndrome (GBS).

BACKGROUND

Based on electrophysiologic and pathologic observations, GBS has been divided into demyelinating and axonal subtypes. The acute motor axonal neuropathy (AMAN) involves predominantly motor nerve fibers with a physiologic pattern suggesting axonal damage, whereas the acute inflammatory demyelinating polyneuropathy (AIDP) involves both motor and sensory nerve fibers with a physiologic pattern suggesting demyelination. In this study, we sought to confirm these observations by correlating sural nerve pathology with electrophysiologic findings in GBS patients.

METHODS

Biopsies of sural nerve from 29 of 50 prospectively studied GBS patients were obtained. Nerves were examined by light and electron microscopy, and with immunocytochemistry for macrophages, lymphocytes, and complement activation products.

RESULTS

Sural nerves from AMAN patients were normal or had only a few (0.1% to 0.7%) degenerating fibers without lymphocytic infiltration or complement activation. One patient with reduced sural sensory nerve action potential classified as acute motor sensory axonal neuropathy (AMSAN) had many degenerating fibers (2.3%) in the sural nerve. All three AIDP patients displayed active demyelination, and in two patients, lymphocytic infiltration and complement activation products were observed on the abaxonal Schwann cell surface.

CONCLUSION

Classification of Guillain-Barré syndrome subtypes based on motor conduction studies correlates closely with pathologic changes seen in sural nerve. In acute motor axonal neuropathy cases, the sural nerve is almost completely spared pathologically. In acute inflammatory demyelinating polyneuropathy cases, macrophage-mediated demyelination and lymphocytic infiltration are common in the biopsies of sural nerves.

Replication ability in vitro and in vivo of equine infectious anemia virus avirulent Japanese strain

An attenuated equine infectious anemia virus (EIAV), V26, was previously prepared by 50 passages of the Japanese virulent strain V70 in primary horse macrophage culture. The horses inoculated with this V26 virus were shown to raise neutralizing antibodies against V70 without any viremia. Here, we investigated the in vitro and in vivo replication ability of V26. Comparison of the long-terminal repeat (LTR) sequences between V26 and V70 revealed a large insertion within the LTR U3 hypervariable region of V26. V26 with the mutation in the LTR showed much higher promoter activity in vitro than V70. This is consistent with the much higher replication rate of V26 in horse primary macrophage cultures compared with V70. In sharp contrast, we failed to identify the V26-specific LTR sequence by PCR, at least in sequential samples of plasma or peripheral blood mononuclear cells derived from three horses until day 62 after V26 inoculation. In contrast, antibody responses to EIAV were observed in all horses. The results suggest that the replication ability of V26 in vivo is extremely low. When one of the horses was subsequently challenged with cell-associated V70, it was found that the horse became PCR positive for EIAV. There was no LTR mutation in EIAV genome in samples periodically prepared from the V70-challenged horse. Thus it was suggested that the LTR mutation in EIAV, which occurs during serial passage in vitro, affects EIAV replication in vitro and in vivo.

Downregulation of endothelial constitutive nitric oxide synthase expression by lipopolysaccharide

Lipopolysaccharide (LPS), a causal agent of sepsis, has been shown to induce systemic nitric oxide (NO) synthesis through complex mechanisms. However, the effect of LPS on endothelial cells is incompletely understood. To investigate the mechanism by which LPS influences the release of NO from endothelial cells, the effect of this compound on endothelial constitutive nitric oxide synthase (ecNOS) was studied in cultured bovine coronary venular endothelial cells. Western and Northern analyses showed that LPS decreased ecNOS expression at the protein and mRNA levels in a time-dependent and dose-responsive manner. Concurrent treatment of the endothelial cells with LPS and a transcription inhibitor, actinomycin D, resulted in decreased ecNOS mRNA within 8 hours. In contrast, treatment with actinomycin D had only a relatively insignificant effect on the ecNOS transcript level. This result suggests that the reduction of ecNOS by LPS resulted from an increased degradation rate of its transcript.

[Synaptic connections between the neurons and catecholaminegic fibres in the hippocampal transplant of rat]

The foetal hippocampal tissue (transplant) at 17th day of embryonic age was implanted into the ventral hippocampus of adult rats (host). The catecholaminergic fibre projections in the hippocampal transplants 90 days after operation were studied by immunohistochemical technique. It was observed that in the host hippocampus there was a large population of TH- immunoreactive slender fibres of only 0.5-1 microns in diameter. These fibres were distributed more densely in the hippocampal hilus and CA3 transparent layers than in molecular layers, but sparsely in pyramidal or granular layers. In the molecular and cellular layers of transplanted hippocampus some thicker (> 1 micron) TH-positive fibers were ended in a relatively dense branching. The immunoelectron-microscopic observations showed that many TH-positive boutons made synaptic contacts with immunonegative dendrites and dendritic spines in the hippocampal transplants, the majority of which were asymmetrical synapses with a 30 nm synaptic cleft and conspicuously thickened postsynaptic membranes. It is concluded that catecholaminergic fibres extend from the host brain into the hippocampal transplant to establish synapses with the target neurons.

Effects of decoctions prepared from Aconitum carmichaeli, Aconitum kusnezoffii and Tripterygium wilfordii on serum lactate dehydrogenase activity and histology of liver, kidney, heart and gonad in mice

Mature ICR mice were randomly divided into groups and treated with various doses (1 mg, 5 mg or 10 mg herb/25 g body weight) of a decoction of one of three following Chinese medicinal herbs: Aconitum carmichaeli, Aconitum kusnezoffi and Tripterygium wilfordii, once daily for 4 days. Twenty four hours after the last injection the animals were bled and the blood samples were stored at -20 degrees C until assay for liver lactate dehydrogenase (LDH) isozyme activity. The livers, kidneys, hearts and gonads were dissected out, immediately fixed in Bouin's fluid, and subsequently processed for histological examination. It was found that the gonads and hearts of the drug-treated mice were histologically similar to those of control animals. After treatment with the lowest dose of the herbs i.e. 1 mg/25 body weight, the liver and kidney did not undergo observable changes. However, the herbs at the doses of 5 mg and 10 mg/25 g body weight produced damaging effects on the liver and kidney, the effects produced by the higher dose being more dramatic. The tissue damage was accompanied by elevations of liver LDH isozyme activity in the serum.

Transcriptional regulation of nitrate reductase mRNA levels by cytokinin-abscisic Acid interactions in etiolated barley leaves

To investigate the mechanisms by which the expression of a specific gene may be modulated by multiple hormones, the regulation of nitrate reductase (NR) mRNA levels by cytokinin and abscisic acid (ABA) was studied in etiolated barley (Hordeum vulgare L. cv Robust) leaves using a barley NR cDNA as a probe. Northern blot analyses of the levels of NR mRNA indicate that accumulation of the mRNA was enhanced by the cytokinin, benzyladenine (BA), and suppressed by ABA and that the hormonal effects on NR gene expression were responsive to dose concentrations (10(-7) to 10(-4) molar). The NR mRNA levels were influenced by the BA/ABA concentration ratios, and the inhibition of the NR transcript levels by ABA was not totally reversed by addition of equal concentrations (10(-7) to 10(-4) molar) of BA. Nuclear runoff transcription studies showed that the level of transcription was suppressed by ABA, and addition of an equal concentration of BA partially reversed the ABA action. Thus, the interaction of cytokinin and ABA on NR gene expression is, at least in part, at the level of transcription.