Investigations of clinical characteristics and inflammatory markers of febrile seizures induced by coronavirus infection

The study of children who experienced with febrile seizures(FS) as a result of COVID-19 infection to gain insight into the clinical characteristics and prognosis of neurological damage, with the aim of improving prevention, diagnosis, and the treatment of neurological complications. This study investigated the clinical features of 53 children with FS who were admitted to Sanya Women and Children's Hospital from December 1, 2022, to January 31, 2023. The results indicated that the duration of convulsion in the case and control group was 7.90±8.91 and 2.67±1.23 (minutes) respectively. The analysis reveals that convulsions occurred within 24 hours in 39 cases (95.12%) of the case group, and in 8 cases (66.7%) of the control group. The difference was statistically significant (P<0.05). Additionally, the case group presented lower counts of WBC and NEU compared to the control group (p<0.05). The findings indicate that convulsions manifest at earlier stages of COVID-19 in children and the last longer than in the control group. It is therefore crucial for healthcare workers to remain attentive to patients with COVID-19 who report fever within 24 hours, and act promptly to implement preventive measures, particularly in cases of prolonged fever. It is essential to integrate the clinical manifestation, particularly convulsions, and the continuous numerical changes of inflammatory factors to assess COVID-19 linked with febrile seizures. In addition, larger-scale multi-center and systematic research are necessary to aid clinicians in monitoring neuropathological signals and biological targets, enabling more equitable diagnosis and treatment plans.

Surgical treatment of tethered cord syndrome showed promising outcome in young children with short duration

OBJECTIVE

Aside from the severity, surgical interventions for the treatment of neurological dysfunctions remain controversial. This study aimed to find factors predicting the benefits of tethered cord syndrome (TCS) surgery.

PATIENTS AND METHODS

80 children with TCS were included and followed up for pre- and post-operative factors along with neurophysiological analysis. Outcomes were assessed by univariate and multivariate analysis.

RESULTS

Surgical treatment not only improved preoperative signs and symptoms in 79% of TCS patients but it showed to be an efficient procedure for the occurrence of future neurological defects. Univariate analysis also revealed that surgical intervention in TCS children (age <1 year) can modulate filar lipoma location and cutaneous abnormalities three months after surgery. Neurophysiological assessment revealed only 5.0% of surgical complications in TCS patients. Two patients had cerebrospinal fluid leakage, and two cases of CNS infection were detected.

CONCLUSIONS

Surgical intervention is highly recommended for the prevention of neurological deficits in children with TCS. Electrophysiological monitoring revealed rare complications following the surgery.

[Comparison of alignment and position of prosthesis between portable accelerometer-based navigation device and conventional instrumentation in total knee arthroplasty with valgus deformity]

Objective: To explore the differences of alignment and position of prosthesis between portable accelerometer-based navigation device (PAD) and conventional instrumentation (CI) in total knee arthroplasty (TKA) with valgus deformity. Methods: Patients with knee osteoarthritis and valgus deformity who underwent primary TKA in Peking University Third Hospital from January 2017 to December 2020 were enrolled in this retrospective study and were divided into PAD group and CI group according to the surgical instruments. Five male patients and 44 female patients were included with a mean age of (67.2±7.0) years. The differences in preoperative general data, preoperative and postoperative alignment between the two groups were studied. Results: A total of 49 patients (25 patients in the PAD group and 24 in the CI group) were enrolled in this study. There were no statistically significant differences in gender, age, height, weight, body mass index, surgical side, preoperative hip-knee-ankle (HKA) angle, preoperative HKA angle deviation, Keblish classification and Ranawat classification between the two groups (all P>0.05). There was no significant difference in the accuracy of postoperative HKA angle (2.0°±1.4° vs 3.0°±2.2°, P=0.082), coronal femoral component angle (CFCA) (1.5°±1.2° vs 2.1°±1.6°, P=0.144) and coronal tibial component angle (CTCA) (1.2°±0.8° vs 1.3°±1.0°, P=0.695) between the two groups; but the standard deviation of the above-mentioned three indices in PAD group were all smaller than those in CI group. The rate of outliers of postoperative HKA angle of the PAD group was smaller than that in the CI group (P<0.05), but there was no significant difference in the rate of outliers of CFCA and CTCA between the two groups (both P>0.05). Conclusion: TKA assisted by PAD can provide good alignment and prosthesis position in patients with valgus deformity, and it is superior to TKA with CI in terms of precision and rate of outliers of postoperative overall alignment of lower extremity.

[Comparison of alignment between computer assisted surgery and personal specific instrumentation in total knee arthroplasty]

Objective: To explore the differences of alignment and operative time between computer assisted surgery (CAS) and personal specific instrumentation (PSI) in total knee arthroplasty (TKA). Methods: Patients with knee osteoarthritis who underwent unilateral primary TKA in Peking University Third Hospital from June 2019 to April 2021 were enrolled in this prospective study and were randomly divided into CAS group and PSI group with random number table. The differences in preoperative general data, operative time, preoperative and postoperative alignment between the two groups were studied. Results: A total of 80 patients were enrolled in this study, including 40 patients in the CAS group with an average age of (68±6) years (male/female, 6/34 cases) and 40 patients in the PSI group with an average age of (69±6) years (male/female, 5/35 cases). There was no significant differences in gender, age, height, weight, body mass index, surgical side, preoperative hip-knee-ankle (HKA) angle, and preoperative HKA angle deviation between the two groups (all P>0.05). The accuracy of sagittal femoral component angle (sFCA) (1.7°±1.2° vs 2.5°±1.4°, P<0.05) and sagittal tibial component angle (sTCA) (1.2°±0.9° vs 2.3°±1.8°, P<0.01) of the CAS group were both smaller than those in the PSI group, but there was no significant difference in the accuracy of postoperative HKA angle, mechanical lateral distal femoral angle (mLDFA) and mechanical medial proximal tibia angle (mMPTA) between the two groups (all P>0.05). The precision of postoperative HKA angle and sTCA of the CAS group were both smaller than those in the PSI group (2.0°±1.0° vs 2.6°±1.7°, 1.2°±0.9° vs 2.3°±1.8°, both P<0.01), but there was no significant differences in the precision of mLDFA, mMPTA and sFCA between the two groups (all P>0.05). The rate of outliers of postoperative HKA angle (10.0% vs 27.5%, P<0.05), sFCA(5.0% vs 20.0%, P<0.05) and sTCA (2.5% vs 22.5%, P<0.01) of the CAS group were all smaller than those in the PSI group, but there was no significant difference in the rate of outliers of mLDFA and mMPTA between the two groups (both P>0.05). CAS group had significantly longer surgical time than the PSI group ((81±12) min vs (52±8) min, P<0.01). Conclusions: CAS is better than PSI in overall coronal alignment and sagittal position of the prosthesis after TKA. However, CAS requires a longer operation time.

Spin-structures of the Bose-Einstein condensates with three kinds of spin-1 atoms

We have performed a quantum mechanic calculation (including solving the coupled Gross-Pitaevskii equations to obtain the spatial wave functions, and diagonalizing the spin-dependent Hamiltonian in the spin-space to obtain the total spin state) together with an analytical analysis based on a classical model. Then, according to the relative orientations of the spins S_A, S_B and S_C of the three species, the spin-structures of the ground state can be classified into two types. In Type-I the three spins are either parallel or anti-parallel to each other, while in Type-II they point to different directions but remain to be coplanar. Moreover, according to the magnitudes of S_A, S_B and S_C, the spin-structures can be further classified into four kinds, namely, p + p + p (all atoms of each species are in singlet-pairs), one species in f (fully polarized) and two species in q (a mixture of polarized atoms and singlet-pairs), two in f and one in q, and f + f + f. Other combinations are not allowed. The scopes of the parameters that supports a specific spin-structure have been specified. A number of spin-structure-transitions have been found. For Type-I, the critical values at which a transition takes place are given by simple analytical formulae, therefore these values can be predict.

[Discussion on optimal duration of pegylated interferon α combined with ribavirin for chronic hepatitis C in HIV-infected patients]

Objective: To investigate the optimal duration of pegylated-alpha interferon (Peg-INFα) combined with ribavirin (RBV) in treating chronic hepatitis C infection in human immunodeficiency virus (HIV)-infected patients. Methods: A multicenter prospective study was conducted. The study subjects were divided into two groups; HIV/HCV co-infections (Group A, n = 158) and control with HCV-monoinfections (Group B, n = 60). All recruited patients received standard Peg-INFα plus RBV therapy. Group A was divided into 3 subgroups according to CD4(+) cell counts: A1 subgroup, 79 cases, CD4(+) counts > 350 cells /μl, who received anti-HCV before combination antiretroviral therapy(cART); A2 subgroup, 45 cases, CD4(+) counts between 200 and 350 cells/μl, who did not start anti-HCV until they could tolerate cART well; A3 subgroup, 34 cases, CD4(+) counts < 200 cells /μl, cART was administered first, and anti-HCV therapy was started when CD4(+) counts > 200 cells/μl. The anti-HCV efficacy of two groups and 3 subgroups were compared. Statistical analysis for normal distribution and homogeneity of variance data was calculated by t-test and the counting data was analyzed by χ (2) test. The Mann-Whitney U test was used for non-normal data. A one-way analysis of variance (ANOVA) was used for the comparison of multiple groups, followed by SNK method. Multiple independent samples were used for non-parametric tests. Results: There was no significant difference in age and baseline HCV RNA levels between groups and subgroups (P > 0.05). By an intent-to-treat (ITT) analysis, in Group A, the ratio of complete early virological response (cEVR) rate was 75.3% (119/158), the ratio of end of treatment virological response (eTVR) rate was 68.4% (108/158), and the ratio of sustained virological response (SVR) rate was 48.7% (77/158); in Group B, the ratio of cEVR rate was 93.3% (56/60), the ratio of eTVR rate was 90.0% (54/60), and the ratio of SVR rate was 71.7% (43/60); The therapeutic index of Group A were lower than those of Group B (P≤0.05). By per-protocol (PP) analysis, the ratio of cEVR rate in Group A [75.2% (88/112)] was still lower than that in Group B [93.3% (56/60)], but no significant differences were found in the ratio of eTVR rate and SVR rate between 2 groups (P > 0.05). Comparing the efficacy of subgroups (A1, A2 and A3) by ITT analysis, the ratios of cEVR rate were respectively 78.5% (62/79), 75.6% (34/45) and 67.6% (23/34); the ratios of eTVR rate were respectively 68.4%(54/79), 80.0%(36/45)and 52.9%(18/34); and the ratios of SVR rate were respectively 41.8%(33/79), 64.4%(29/45)and 44.1%(15/34). The ratio of eTVR in subgroup A2 was obviously higher than that in subgroup A3 and the ratio of SVR in subgroup A2 was statistically higher than that of subgroup A1(P≤0.05). However, by PP analysis, no significant differences of the therapeutic indexes were found among the respective subgroups (P > 0.05). Conclusion: HIV-HCV co-infected patients would have better anti-HCV efficacy with Peg-INFα-2a plus RBV than HCV- monoinfected patients. The best time for initiating anti-HCV therapy in HIV-HCV co-infected patients is when CD4(+) counts 200 cells/ μl.

Primary vs myocutaneous flap closure of perineal defects following abdominoperineal resection for colorectal disease: a systematic review and meta-analysis

AIM

Perineal wound complications after abdominoperineal resection (APR) have become a major clinical challenge. Myocutaneous flap closure has been proposed in place of primary closure to improve wound healing. We conducted this comprehensive meta-analysis to evaluate the current scientific evidence of primary closure vs myocutaneous flap closure of perineal defects following APR for colorectal disease.

METHODS

We systematically searched the MEDLINE, Embase, PubMed, Web of Science and Cochrane Library databases to identify all relevant studies. After data extraction from the included studies, meta-analysis was performed to compare perioperative outcomes of primary closure and myocutaneous flap closure.

RESULTS

Eighteen studies with a total of 17 913 patients (16 346 primary closure vs 1567 myocutaneous flap closure) were included. We found that primary closure was significantly associated with higher total perineal wound complications (P = 0.007), major perineal wound complications (P < 0.001) and perineal wound infection (P = 0.001). On the other hand, myocutaneous flap closure takes more operation time (P < 0.001) and increases the risk of perineal wound dehiscence (P = 0.01), deep surgical site infection (P < 0.001), enterocutaneous fistulas (P = 0.03) and return to the operating room (P = 0.0005). There were no significant differences between the two groups for other outcomes.

CONCLUSIONS

This is the first systematic review with meta-analysis comparing primary closure with myocutaneous flap closure of perineal defects after APR for colorectal disease. Although taking more operation time and an increased risk of specific complications, the pooled results have validated the use of myocutaneous flaps for reducing total/major perineal wound complications. More investigations are needed to draw definitive conclusions on this dilemma.

[Prevalence of biomass fuel exposure in women aged 40 years and older in China, 2014]

Objective: To understand the prevalence of biomass fuel exposure in women aged ≥40 years in China during 2014-2015, and provide evidence for the prevention and control of bio-fuel exposure. Methods: All participants were selected from a national representative cross-sectional survey during 2014-2015 in the mainland of China. A multi-stage stratified cluster sampling strategy was used. A total of 37 795 women aged ≥40 years received a face-to-face questionnaire survey at 125 surveillance points in 31 provinces. The level of biomass fuel exposure was analyzed after complex sample weighting to represent the overall Chinese women aged ≥40 years. Results: A total of 37 777 women were included in the analysis. With complex weighting, the rate of biomass fuel exposure in Chinese women aged ≥40 years was 35.8% (95%CI: 29.6%-42.1%), the exposure rate was higher in rural women than in urban women (P<0.001). The biomass fuel exposure rate was highest in northeastern and lowest in northern areas of China (χ(2)=17.03, P=0.009). The estimated biomass fuel exposure rate decreased with the increase of educational level (P<0.001). Conclusion: The prevalence of biomass fuel exposure is high in women aged ≥40 years in China, especially in those in rural areas. The exposure level differs with age and area. Appropriate measures should be taken to reduce the level of biomass fuel exposure in Chinese women.

[Experimental study scavenging effect of paraquat by hemoperfusion]

Objective: To determine the scavenging effect and the change of metabolism of paraquat (PQ) using hemoperfusion (HP) once and twice within 12 hours after intoxication and explore the better scheme of HP. Methods: 18 beagles were randomly divided into 3 groups. Single HP group, Double HP group and Control group. Peripheral veins blood was collected at different times within 48 hours after exposure in each group. Toxin concentration was measured, analyzed and compared among 3 groups. Results: 6 hours after exposure, Single HP group and Double HP group has finished the first HP treatment, and the concentration of PQ was lower than that of the control group, the difference was statistically significant (P<0.05) . 10 hours after exposure, there was no statistical difference of toxin concentration among 3 groups (P>0.05) . 12 hours after exposure, Double HP group has finished the second HP treatment, the concentration of PQ was significantly lower than that of Single HP group and Control group (P<0.05) . 24 hours and 48 hours after exposure, there was no statistical difference of toxin concentration among 3 groups (P>0.05) . Statistical difference were not observed in toxicokinetical parameters among 3 groups (P>0.05) . Conclusion: HP treatment once and twice within 12 hours after intoxication could effectively reduce the toxin concentration in the peripheral veins blood after HP for about 4 hours, then the toxin concentration would return to the same level as Control group quickly. It was suggested that at the beginning of poisoning, HP treatment once or twice could not significantly change the metabolism of paraquat.

Singularity in the matrix of the coupled Gross-Pitaevskii equations and the related state-transitions in three-species condensates

An approach is proposed to solve the coupled Gross-Pitaevskii equations (CGP) of the 3-species BEC in an analytical way under the Thomas-Fermi approximation (TFA). It was found that, when the strength of a kind of interaction increases and crosses over a critical value, a specific type of state-transition will occur and will cause a jump in the total energy. Due to the jump, the energy of the lowest symmetric state becomes considerably higher. This leaves a particular opportunity for the lowest asymmetric state to replace the symmetric states as the ground state. It was further found that the critical values are related to the singularity of either the matrix or a sub-matrix of the CGP. These critical values are not arising from the TFA but inherent in the CGP, and they can be analytically expressed. Furthermore, a model (in which two kinds of atoms separated from each other asymmetrically) has been proposed for the evaluation of the energy of the lowest asymmetric state. With this model the emergence of the asymmetric ground state is numerically confirmed under the TFA. The theoretical formalism of this paper is quite general and can be generalized for BEC with more than three species.

Effects of lipopeptide carboxymethyl chitosan nanoparticles on Staphylococcus aureus biofilm

This study aims to evaluate the effect of lipopeptide carboxymethyl chitosan nanoparticles on Staphylococcus aureus biofilm as part of the development of a new anti-biofilm material. The study had three stages. Firstly, we assessed the Staphylococcus aureus capability to form biofilm and enumerated the number of attached bacteria and free bacteria; secondly, we determined the inhibitory effect of different concentrations of Bacillus natto antimicrobial lipopeptid- carboxymethyl chitosan (BNAP-CMCS) nanoparticles added at different times on biofilm formation capability and the numbers of free bacteria and attached bacteria. Lastly, we tested the scavenging effect of BNAP-CMCS nanoparticles on biofilm formation and number of attached bacteria. The results showed that the amount of attached bacteria quickly increased over time and reached the maximum after 24 h of culture. The BNAP-CMCS nanoparticles had the greatest effect on biofilm inhibition at the concentration of 1 MIC, after 8 h of culture, and the effect was dose-dependent. The BNAP-CMCS nanoparticles had decreased also the numbers of free and attached bacteria in a dose-dependent fashion, after 8 hours of culture. The scavenging effect of BNAP-CMCS nanoparticles on free and attached bacteria was maximum at 6 MIC. In conclusion, lipopeptide carboxymethyl chitosan nanoparticles had a good inhibition and scavenging effect on the formation of Staphylococcus aureus biofilm and the growth of surface-attached bacteria.

Long-term outcome of HLA-haploidentical hematopoietic stem cell transplantation without in vitro T-cell depletion based on an FBCA conditioning regimen for hematologic malignancies

Haploidentical hematopoietic stem cell transplantation (haplo-HSCT) is an alternative for patients who need a transplant without having conventional donors. One hundred and five consecutive patients with hematologic malignancies who underwent G-CSF-primed peripheral blood haplo-HSCT without in vitro T-cell depletion in our single center were reported in this study. Patients were categorized into the intermediate-risk group (n=28) or high-risk group (n=77) according to the risk stratification. The conditioning regimen included fludarabine, busulfan, cyclophosphamide and anti-lymphocyte globulin. The cumulative incidence of grades II-IV acute GvHD (aGvHD) on day +100 was 21.9%, and that of grades III-IV aGvHD was 14.3%. The 2-year cumulative incidence of total chronic GvHD (cGvHD) was 24.1%, and that of extensive cGvHD was 5.6% in 83 eligible patients. The 3-year cumulative incidence rates of relapse and no relapse mortality were 21.9% and 30.5%, respectively. After a median follow-up of 35 months, the 3-year probabilities of overall and disease-free survival for the intermediate-risk and high-risk groups were 63.2% and 39.8% and 61.2% and 32.2%, respectively. In multivariate analysis, the outcome of survival (overall survival and disease-free survival) was associated with the risk stratification, disease status at transplant and dose of infused mononuclear cells. Our results suggest that unmanipulated peripheral blood stem cell allograft performed with fludarabine, busulfan, cyclophosphamide and anti-lymphocyte globulin conditioning regimen is feasible.

Effect of IL-18 gene promoter polymorphisms on prostate cancer occurrence and prognosis in Han Chinese population

Interleukin-18 (IL-18) has been implicated in a wide variety of cellular functions that affect the biological response to tumors. However, there is insufficient evidence to prove that IL-18 gene variants are associated with risk of prostate cancer. We examined a possible association between two promoter polymorphisms, -137G/C (rs187238) and -607C/A (rs1946518), in the IL-18 gene and prostate cancer occurrence and prognosis in Han Chinese. We used a high-resolution melting method to genotype these two polymorphisms in 375 Chinese Han patients with prostate cancer and in 400 age-matched healthy controls. A hundred and eighty-one prostate cancer patients who had been receiving androgen deprivation therapy, including operational and medical castration, were enrolled to follow-up in this study. Carriers of the GG genotype of the -137G/ C polymorphism had a 2.165-times higher risk of prostate cancer progression than carriers of GC [95% confidence interval (CI) = 1.270-3.687]. Patients with the GG genotype at clinical stages III and IV also had significantly lower rates of progression-free survival (relative risk = 2.174, 95%CI = 1.211-3.906). However, we found no significant association of genotype or allele distributions of these two polymorphisms with occurrence of prostate cancer. We conclude that there is evidence that the IL-18 gene promoter polymorphism -137G/ C influences the prognosis of prostate cancer patients in androgen deprivation therapy, although neither of the two SNPs contributes to prostate cancer development.

iPSCs are transcriptionally and post-transcriptionally indistinguishable from fESCs

Induced pluripotent stem cells (iPSCs) are generated by reprogramming mouse or human somatic cells to a pluripotent state by introducing key transcription factors and have great therapeutic potential. It has been illustrated that the transcriptional and post-transcriptional profiles of nuclear-transferred embryonic stem cells (ntESCs) is identical to those of embryonic stem cells derived from fertilized blastocysts (fESCs). Although iPSCs seem to be indistinguishable from fESCs, the degree of transcriptomic and proteomic similarity among iPSCs, ntESCs, and fESCs has not yet been elucidated completely. To investigate whether iPSCs and fESCs have similar therapeutic potential, we compared mRNA and protein pro?les of mouse iPSC, ntESCs, and matching fESCs lines using microarray technology, iTRAQ method, and bioinformatic analyses. Real-time PCR, two-dimensional LC, and MS/MS analyses were further conducted to study the expression of speci?c transcripts and identify and quantitate 929 proteins. Our results demonstrate that, like ntESCs, the iPSC and matching fESCs lines have very similar transcriptional and protein expression profiles. This is consistent with their similar developmental potential.

Bone growth during daily or intermittent calcitriol treatment during renal failure with advanced secondary hyperparathyroidism

Calcitriol is a standard therapy for secondary hyperparathyroidism in chronic renal failure. We evaluated whether the effect of daily or intermittent calcitriol administration is more efficient in enhancing bone growth in renal failure with advanced secondary hyperparathyroidism in weanling 5/6 nephrectomized rats loaded with phosphorus to induce severe secondary hyperparathyroidism. The animals were treated daily or three times weekly with calcitriol for 4 weeks but the total weekly dose of calcitriol was the same. Although calcitriol increased the serum calcium, it did not lower parathyroid hormone (PTH) or improve tibia and body length. Animals with renal failure and advanced secondary hyperparathyroidism had decreased PTH/PTHrP, which was accompanied by an increase in the cyclin kinase inhibitor p57(Kip2). Calcitriol treatment upregulated the PTH/PTHrP receptor but also increased inhibitors of cell proliferation such as p21(Waf1/Cip1), IGFBP3, and FGFR3. Calcitriol also enhanced markers of chondrocyte differentiation, such as IGF1, Vitamin D receptor, FGF23, and bone morphogenetic protein-7. Receptor activator of nuclear factor-kappabeta ligand levels improved with calcitriol treatment but without changes in osteoprotegerin suggesting an enhancement of osteo/chondroclastogenesis and mineralization. Overall, both daily and intermittent calcitriol had similar effects on endochondral bone growth in phosphorus-loaded rats with renal failure.

Pre-concentration of non-uniform field electrophoresis for sample introduction of capillary electrophoresis

A new sample introduction method of capillary electrophoresis, in which field-amplified sample injection was combined with a pre-concentration of non-uniform field electrophoresis, is presented in this paper. With an additional pre-concentration voltage applied to sample solution, a non-uniform electric field was generated, with which analytical cations or anions were pre-concentrated around an electrode adjacent to the injection end of capillary. After the pre-concentration, analytical ions were injected into the capillary and stacked at the boundary between sample and buffer solution inside capillary by field-amplified injection technique. In contrast to the conventional field-amplified injection, larger concentration factor and higher analytical sensitivity were obtained with the improved pre-concentration method. Its concentration factor was about 10 approximately 15 fold as that of field-amplified sample injection.

Experimental investigation on moving chemical reaction boundary theory for weak-acid-strong-base system with background electrolyte KCl in large concentration

In this report, the moving chemical reaction boundary (MCRB) was formed with the weak acid of acetic acid (HAc) and the strong alkali of NaOH, coupled with the excess of background electrolyte KCl. The experiments were compared with the predictions by the moving chemical reaction boundary equation (MCRBE). It is very interesting that (1) the experimental results are in good agreement with the predictions with the original MCRBE if the MCRB is an anodic moving boundary, (2) however, the experiments are extremely far away from the predictions with the original MCRBE if a cathodic moving boundary. Hence, the original MCRBE must be corrected under the later situation of cathodic moving MCRB. The corrected MCRBE was well quantitatively proved to be valid for the cathodic moving MNRB formed with the same electrolytes of HAc, NaOH and KCl.

[Study on sampling preconcentration method combining electrostacking with isotachophoresis in capillary electrophoresis]

A sampling preconcentration method combining electrostacking with isotachophoresis is presented in this paper. The optimum conditions for electrostacking and isotachophoresis were investigated. With the preconcentration conditions of 70 s electrostacking and 40 s isotachophoresis, two medicines, propranolol and metoprolol, with similar structures were separated by capillary zone electrophoresis. The working voltage for all the steps was 15 kV. Being adjusted to pH 4.0, 30 mmol/L NaAc-HAc, 30 mmol/L beta-alanine-HAc and 1.5 mmol/L NaAc-HAc were employed as the background, viz. leading, terminating and sample buffer solutions respectively. In comparing with the conventional electro-migration injection, the enhancement factors in peak height of the present method were about 250 and 160 for propranolol and metoprolol respectively. Total analysis time was similar to that of the conventional one.

Corrections to moving chemical reaction boundary equation for weak reactive electrolytes under the existence of background electrolyte KCl in large concentrations

In this report, the moving chemical reaction boundary (MCRB) was formed by the weak reaction electrolytes of NH3.H2O and CH3COOH under the existence of background electrolyte KCl in large concentrations, the experiments were compared with the predictions by the moving chemical reaction boundary equation (MCRBE) for weak reactive electrolytes. It was found that the experimental results are far from the predictions with the MCRBE. So the MCRBEs must be corrected under the given experimental conditions. The corrected MCRBEs are given for the MCRB formed with weak reactive electrolytes coupled with KCl at high concentrations.

Three-hybrid strategy reveals a peptide segment that specifically binds to the 3'-untranslated region of NF-IL6 mRNA

The 3'UTR of eukaryotic mRNA is an important regulation region, on which many trans factors act. In recent years, a series of 3'UTRs were shown to have tumor suppressor function, including the 3'UTR of the human nuclear factor for interleukin-6 (NF-IL6 3'UTR). To understand molecular basis for this function, we have tried to isolate genes encoding protein factors acting on the RNA of NF-IL6 3'UTR. Here we show that, by using a yeast three-hybrid system, a cDNA fragment was successfully isolated. This cDNA was allowed to express in E. coli, and its expression product, a polypeptide of ca. 70 amino acids long, was shown to specifically bind to the NF-IL6 3'UTR RNA. A search in GenBank did not reveal homologous sequences. Therefore, this cDNA fragment may be a part of the gene of a novel NF-IL6 3'UTR specific binding protein.

Regulation of sucrase and lactase in Caco-2 cells: relationship to nuclear factors SIF-1 and NF-LPH-1

Recent studies suggest the importance of two transcription factors, Cdx-2 and NF-LPH-1, in the regulation of sucrase-isomaltase (SI) and lactase-phlorizin hydrolase (LPH) gene expression, respectively. Cdx-2 accounts for the tissue specificity of sucrase expression (16), and NF-LPH-1 varies with postnatal changes in lactase activity, suggesting a role in its developmental regulation (22). We used electrophoretic mobility shift assays to study the relationship of Cdx-2 and NF-LPH-1 to SI and LPH gene expression in Caco-2 cells to provide evidence regarding the role of these factors in the development of sucrase and lactase with cellular differentiation. We found that Cdx-2 levels correlated with SI expression and that NF-LPH-1 did not correlate with LPH expression. These studies suggest a role for Cdx-2 but not for NF-LPH-1 in the development of carbohydrase expression in these cells.

[Studies on the hidropoiesis of the decoction of gui-zhi tang in mice and rats]

Effects of the Decoction of Gui Zhi Tang (DGZT) on the hidropoiesis of animal paw in different pathophysiological conditions were studied with the examination of sweat stains. The diaphoresis was found in normal rats when 2.5-10.0 g crude drugs/kg p.o. of the DGZT was administrated. The diaphoretic function was also promoted by DGZT in mice infected with influenza virus which the function was gradually suppressed. The decoction had the action of bidirectional regulation and normalization in polyhidrosis induced by aminopyrine or in hypohidrosis induced by atropine on rats.

Structure and sequence determination of the gene encoding human salivary statherin

Human statherin (STT) is a low-Mr (43 amino acids) acidic phosphoprotein secreted mainly by salivary glands. It acts as an inhibitor of precipitation of Ca.phosphate salts in the oral cavity. DNA (12.2 kb) was isolated from human genomic phage lambda libraries as a series of overlapping clones, and the nucleotide sequence of the STT-encoding gene (STT) was determined. The transcribed region spans 6.5 kb and contains six exons and five introns. Upstream DNA (1.6 kb) was also sequenced and a number of possible regulatory elements were identified. The exon-intron boundaries of the STT gene roughly coincide with the protein-coding regions of the mRNA and with the functional domains of STT. This pattern of organization has been seen in a variety of eukaryotic genes and is consistent with the domain theory of gene evolution.

Synthesis of methylisoamylnitrosamine from isoamylamine by fungi (Fusarium moniliforme)

Methylisoamylnitrosamine, a carcinogenic N-nitroso compound, has been formed in glucose ammonium nitrate medium containing 150 mg of isoamylamine (a primary amine) inoculated with a common fungus (Fusarium moniliforme Sheldon), to which 400 mg NaNO2 are added after incubation for 7-8 days at 28 degrees C. No such compound has been found in control samples without fungi or isoamylamine. This paper reports a method of experimental synthesis of the nitrosamine by F. moniliforme strains 82-01 and 83-01, using isoamylamine and NaNO2, as well as the analysis of the compound by GC/MS and GC/TEA.

Effect of calcium on proteolytic activity and conformation of hemorrhagic toxin I from five pace snake (Agkistrodon acutus) venom

AaHI, a proteolytic hemorrhagic toxin from A. acutus venom, contains one g-atom Zn per mole protein and 2 g-atoms Ca per mole protein. AaHI is activated by calcium and slightly inhibited by zinc. When treated with EDTA, AaHI is completely inactivated. When dialyzed against 1,10-O-phenanthroline, 50-80% of the metal content and activities are lost, while 90% of the hemorrhagic and proteolytic activities are retained when dialyzed against 1,10-O-phenanthroline containing 5mM Ca2+. The results suggest that calcium is essential for the hemorrhagic and proteolytic activities. The circular dichroism spectra show that calcium may play an important role in maintaining a proper structure for AaHI. The function of zinc is not clear.

Preneoplastic and neoplastic progression during hepatocarcinogenesis in mice injected with diethylnitrosamine in infancy

Basophilic hepatic foci, nodules, and trabecular hepatocellular carcinomas, collectively referred to as focal hepatic lesions, were induced by single injections of 5.0 micrograms of diethylnitrosamine (DEN) per gram body weight in 15-day-old C57BL/6J X C3HeB/FeJ F1 (B6C3 F1) mice. Groups of eight experimental and eight control mice were killed at 3 days and at 1, 2, 4, 10, 20, 28, 36 and 41 weeks after injection. The only observable acute hepatic toxic effect of DEN, a mild steatosis, was noted at 3 days, but this had disappeared by 7 days following injection. Basophilic foci, composed entirely of altered hepatocytes, were first noted, when very small, at 10 weeks. At later times, some of the foci also contained small collections of proliferated ductules, apparently a result of secondary ingrowth from nearby interlobular bile ducts. The hepatocytes within basophilic foci were characterized by their abundant cytoplasmic RNA, a high nuclear to cytoplasmic ratio (two times greater than normal), which gave them a "crowded appearance," and decreased glucose-6-phosphatase activity. During the course of the study, basophilic foci appeared to increase in size and number. Cytologic anaplasia also became more evident, ultimately culminating in the development of typical trabecular hepatocellular carcinomas by 44 weeks. Invasion of hepatic veins by basophilic foci, first noted at 10 weeks, was prominent by 20 weeks and indicated that many of the lesions manifested this characteristic of malignancy well in advance of the anaplastic features that are also diagnostic of hepatocellular carcinoma. The high growth rates of basophilic foci were confirmed by their greatly increased 3H-thymidine labeling indices, which were 20 times greater than background hepatocytes at 20 weeks following DEN injection. Tumor progression during the course of the study was also suggested by a doubling of labeling indices of hepatocytes in the basophilic foci between 20 to 28 weeks. (The term tumor progression is used in a broad biological sense to encompass any or all of the qualitative and quantitative changes describing the stepwise development of initiated cells to highly malignant neoplasms. This definition differs from the more clinical usage which restricts the process to qualitative changes during the late stages in the development of fully autonomous neoplasms.) An analysis of the number and size of transections through basophilic foci and in some cases, actual reconstructions of the foci from serial sections, indicated that, in aggregate, they grew exponentially between 10 to 36 weeks, with a volume doubling time of 2.5 weeks. The combined morphologic and kinetic data support the view that trabecular hepatocellular carcinomas develop from basophilic foci. Because of their ease of quantitation on conventional H&E stained sections, their rather uniformly spherical shapes, and the high probability of their clonal origin, the induced focal hepatic lesions should provide a useful model for studying tumor growth kinetics during carcinogenesis.