Generalized granuloma annulare in an infant clinically manifested as papules and atrophic macules: A case report.

BACKGROUND: Granuloma annulare (GA) has diverse clinical manifestations including papules, plaques, and nodules on the extremities that are skin-colored, pink, or purple. Approximately 15% of all GA cases are considered generalized GA. CASE SUMMARY: Herein, we describe the case of a pediatric patient who initially presented with papules and later developed generalized atrophic macules. Upon examination, two different morphologic lesions were histopathologically confirmed: Epithelioid nodular GA and scattered histiocytic infiltrative GA. This patient exhibited rare clinical manifestations that differed throughout the course of the disease. The varying histopathological types and clinical manifestations of GA may be linked to the different stages of the disease. CONCLUSION: This rare case demonstrates the different histopathological features of different stages and clinical manifestations of granuloma annulare in an infant.

[Leukemia Genotype Analysis of Children with Acute Lymphoblastic Leukemia in Yunnan Area].

OBJECTIVE: To analyze 43 leukemia genes in children with acute lymphoblastic leukemia (ALL) in Yunnan province, and provide the basis for the diagnosis and treatment of children with ALL in this area. METHODS: The clinical data of 428 children with newly diagnosed ALL in Yunnan area from January 2015 to December 2020 were retrospectively analyzed. Multiple nested PCR technology was used to detect 43 common leukemia genes. RESULTS: Among the 428 children with ALL, 159 were positive for leukemia genes, with a positive rate of 37.15% (159/428), and a total of 15 leukemia genes were detected. Among the 159 leukemia gene-positive children, ETV6-RUNX1+ accounted for 25.79% (41/159), followed by E2A-PBX1+ and BCR-ABL+, accounting for 24.53% (39/159) and 23.27% (37/159) respectively. MLL+ accounted for 6.29% (10/159), WT1+ accounted for 4.40% (7/159), IKZF1 gene deletion and CRLF2+ accounted for 3.77% (6/159) respectively. The positive rate of MLL (46.15%) was the highest in ＜1-year old group, the positive rate of ETV6-RUNX1 (10.56%) was the highest in 1-10-year old group, and BCR-ABL+ rate (23.65%) was the highest in >10-year old group. The distribution of leukemia genes in different age groups was statistically significant (P <0.05). CONCLUSION: The most common fusion gene of children with ALL in Yunnan is ETV6-RUNX1, followed by E2A-PBX1 and BCR-ABL.

Clinical and whole exome sequencing findings in children from Yunnan Yi minority ethnic group with retinitis pigmentosa: two case reports.

BACKGROUND: Retinitis pigmentosa is a group of rare hereditary retinal dystrophy diseases that lead to difficulty seeing at night, progressive loss of peripheral field vision (tunnel vision), and eventual loss of central vision. However, a genetic cause cannot be determined in approximately 60% of cases. CASE PRESENTATION: Two non-consanguineous Yi minority ethnic group families who have a 6.4-year-old boy and a 0.5-year-old boy, respectively, were recruited for genetic diagnosis. Here, we used whole-exome sequencing to detect mutations in the genes of the probands of the retinitis pigmentosa families, and Sanger sequencing to confirm the causal mutations identified by whole exome sequencing. In addition, we report two cases with retinitis pigmentosa caused by RDH12 (c.524C > T) and PRPF4 (c.1273G > A) pathogenic mutations. CONCLUSIONS: These results might extend the mutation spectrum of known retinitis pigmentosa genes and give these two Yi minority ethnic group families from Yunnan more precise genetic counseling and more specific prognoses.

Elastic fiber degradation in the development of pediatric granuloma annulare: Report of 39 cases.

BACKGROUND: Granuloma annulare (GA) has diverse clinical manifestations, multiple subtypes, and unknown etiology and pathogenesis. Existing studies regarding GA in children are scarce. AIM: To examine the correlation between clinical manifestation and histopathology of pediatric GA. METHODS: A total of 39 patients under 18 years of age with both a clinical and pathological diagnosis of GA at Kunming Children's Hospital from 2017 to 2022 were retrieved. Their medical records were consulted, and clinical data of the children were recorded and summarized, including gender, age, disease site, etc. Existing wax blocks of skin lesion specimens of children and pathological films were retrieved for further study and relevant histology, including hematoxylin-eosin, Alcian blue, elastic fiber (Victoria blue-Lichon red method), and antacid staining. Finally, the children's clinical manifestations, histopathological results, and special staining characteristics were analyzed. RESULTS: The clinical manifestations of granuloma annulare in children were diverse: 11 cases presented with a single lesion, 25 with multiple lesions, and 3 with generalized lesions. The pathological typing comprised histiocytic infiltration, palisading granuloma, epithelioid nodular, and mixed types in 4, 11, 9, and 15 cases, respectively. Thirty-nine cases were negative for antacid staining. The positive rate of Alcian blue staining was 92.3%, and that of elastic fiber staining was 100%. The degree of elastic fiber dissolution and granuloma annulare histopathological typing were positively correlated (r = 0.432, P < 0.05). No correlation was found between clinical presentation and histopathological typing of the granuloma annulare in children. In the pathological diagnosis of granuloma annulare, the positive elastic fiber staining rate was higher than that of Alcian blue staining. A correlation was found between elastic fiber dissolution degree and histopathological staging. However, the differences in pathological staging may have been related to the pathological manifestation of granuloma annulare at different periods. CONCLUSION: Elastic fiber degradation may be a critical step in the pathogenesis of pediatric granuloma annulare. This is also one of the first studies focused on granuloma annulare in children.

[Risk factors for nosocomial infection of carbapenem-resistant Klebsiella pneumoniae in children: a single-center matched case-case-control study]. / å„¿ç«¥ç¢³é’éœ‰çƒ¯ç±»è€è¯è‚ºç‚Žå ‹é›·ä¼¯èŒåŒ»é™¢æ„ŸæŸ“çš„å±é™©å› ç´ åˆ†æžï¼šå•ä¸­å¿ƒé å¯¹ç— ä¾‹-ç— ä¾‹-å¯¹ç §ç ”ç©¶.

OBJECTIVES: To identify risk factors for carbapenem-resistant Klebsiella pneumoniae (CRKP) infection and death in hospitalized children in pediatric hospitals, and to provide a basis for the prevention and control of such infection. METHODS: This is a matched case-case-control study. The medical data of 81 children with CRKP infection and 81 children with carbapenem-sensitive Klebsiella pneumoniae (CSKP) infection who were hospitalized in Kunming Children's Hospital from January 2019 to October 2021 were retrospectively analyzed. A total of 162 children without CRKP or CSKP infection were enrolled as the control group. The association of underlying disease, previous hospitalization exposure, and current hospitalization exposure with CRKP infection and death was identified. RESULTS: Compared with the control group, there was a higher correlation between the history of hospitalization in the past 3 months and CRKP and CSKP infections (OR=14.25 and 10.07 respectively, P<0.01). The use of carbapenem in the past 3 months (OR=16.54, P<0.01) and central venous catheterization during the current hospitalization (OR=33.03, P<0.01) were risk factors for CRKP infection. The use of carbapenem in the past 3 months (OR=28.33, P<0.01) and empirical antibiotic use during the current hospitalization (OR=14.5, P<0.01) were risk factors for death of the children with CRKP infection. CONCLUSIONS: The history of hospitalization and the history of treatment with carbapenems in the past 3 months and invasive procedure after admission are leading influencing factors for CRKP infection and prognosis. It is necessary for pediatric hospitals to conduct CRKP screening on admission, standardize antibiotic use, and strengthen nosocomial infection surveillance, so as to decrease the incidence of CRKP infection.

Diagnostic value of bone marrow cell morphology in visceral leishmaniasis-associated hemophagocytic syndrome: Two case reports.

BACKGROUND: Visceral leishmaniasis related-hemophagocytic lymphohistiocytosis (VL-HLH) is a hemophagocytic syndrome caused by Leishmania infection. VL-HLH is rare, especially in nonendemic areas where the disease is severe, and mortality rates are high. The key to diagnosing VL-HLH is to find the pathogen; therefore, the Leishmania must be accurately identified for timely clinical treatment. CASE SUMMARY: We retrospectively analyzed the clinical data, laboratory examination results, and bone marrow cell morphology of two children with VL-HLH diagnosed via bone marrow cell morphology at Kunming Children's Hospital of Yunnan, China. Both cases suspected of having malignant tumors at other hospitals and who were unresponsive to treatment were transferred to Kunming Children's Hospital. They are Han Chinese girls, one was 2 years old and the other one is 9 mo old. They had repeated fevers, pancytopenia, hepatosplenomegaly, hypertriglyceridemia, and hypofibrinogenemia over a long period and met the HLH-2004 criteria. Their HLH genetic test results were negative. Both children underwent chemotherapy as per the HLH-2004 chemotherapy regimen, but it was ineffective and accompanied by serious infections. We found Leishmania amastigotes in their bone marrow via morphological examination of their bone marrow cells, which showed hemophagocytic cells; thus, the children were diagnosed with VL-HLH. After being transferred to a specialty hospital for treatment, the condition was well-controlled. CONCLUSION: Morphological examination of bone marrow cells plays an important role in diagnosing VL-HLH. When clinically diagnosing secondary HLH, VL-HLH should be considered in addition to common pathogens, especially in patients for whom HLH-2004 chemotherapy regimens are ineffective. For infants and young children, bone marrow cytology examinations should be performed several times and as early as possible to find the pathogens to reduce potential misdiagnoses.

Next generation sequencing of RB1gene for the molecular diagnosis of ethnic minority with retinoblastoma in Yunnan.

BACKGROUND: Retinoblastoma is a rare intraocular malignancy and typically initiated by inactivating biallelic mutations of RB1 gene. Each year, ~ 8000 children worldwide are diagnosed for retinoblastoma. In high-income countries, patient survival is over 95% while low-income countries is ~ 30%.If disease is diagnosed early and treated in centers specializing in retinoblastoma, the survival might exceed 95% and many eyes could be safely treated and support a lifetime of good vision. In China, approximate 1100 newly diagnosed cases are expected annually and 28 hospitals covering 25 provinces established centers classified by expertise and resources for better treatment options and follow-up. Comparing with other province of eastern China, Yunnan province is remote geographically. This might result that healthcare staff have low awareness of the role of genetic testing in management and screening in families. METHODS: The patients with retinoblastoma were selected in Yunnan. DNA from blood was used for targeted gene sequencing. Then, an in-house bioinformatics pipeline was done to detect both single nucleotide variants and small insertions/deletions. The pathogenic mutations were identified and further confirmed by conventional methods and cosegregation in families. RESULTS: Using our approach, targeted next generation sequencing was used to detect the mutation of these 12 probands. Bioinformatic predictions showed that nine mutations were found in our study and four were novel pathogenic variants in these nine mutations. CONCLUSIONS: It's the first report to describe RB1 mutations in Yunnan children with retinoblastoma. This study would improve role of genetic testing for management and family screening.

A novel mutation of the PAX3 gene in a Chinese family with Waardenburg syndrome type I.

BACKGROUND: To analyze the clinical phenotypes and genetic variants of a Chinese family with Waardenburg syndrome (WS) and to explore the possible molecular pathogenesis of WS. METHODS: The clinical data from a patient and his family were collected. The genomic DNA of the patient and his family was purified from their peripheral blood. All exons and flanking sequences of the MITF, PAX3, SOX10, SNAI2, END3, and EDNRB genes were investigated through high-throughput sequencing. Based on the results of high-throughput sequencing, genetic variants in the patient and his family were verified and analyzed by Sanger sequencing. RESULTS: The patient was diagnosed with typical WS1 that manifested in hearing impairment, inner canthus ectopia and heterochromic iris. Sanger sequencing revealed the pathogenic heterozygous c.420-424de1CGCGGinsTTAC mutation in the PAX3 gene in the proband, which is a frameshift mutation that changed the amino acid sequence of the PAX3 protein from AVCDRNTVPSV to YSVIETPCRQ* (* refers to a stop codon) from amino acids 141-151. The stop codon induced by this mutation resulted in the truncation of the PAX3 protein. The same mutation sites were also found in the mother and younger sister of the proband. No previous report of this mutation was found in the Human Gene Mutation Database. CONCLUSION: The novel heterozygous c.420-424de1CGCGGinsTTAC mutation is the molecular pathological cause for WS1 in our patient. The clinical and genetic characterization of this family with WS1 elucidated the genetic heterogeneity of PAX3 in WS1. Moreover, the mutation detected in this case has expanded the database of PAX3 mutations.

MiR-125b regulates the proliferation and metastasis of triple negative breast cancer cells via the Wnt/ß-catenin pathway and EMT.

BACKGROUND/AIM: MiR-125b plays an important role in breast cancer. The current study was to explore the expression and function of miR-125b in triple negative breast cancer cells. MATERIALS AND METHODS: The expression of miR-125b in human TNBC samples and cell lines were examined by qRT-PCR. MTT, scratch assays and transwell assays were utilized to observe the proliferation, migration and invasion ability. MiR-125b's target gene and downstream signaling pathways were investigated by Luciferase Reporter Assays, qRT-PCR, immunofluorescence assays and western bolt. RESULTS: MiR-125b was highly expressed in human TNBC tissues and cell lines. Inhibiting miR-125b expression suppressed the proliferation, cell migration and invasion. The three-prime untranslated region (3´-UTR) of adenomatous polyposis coli (APC) mRNA contains miR-125b binding sites, and inhibiting miR-125b expression suppressed the activity of the intracellular Wnt/ß-catenin pathways and EMT. CONCLUSION: Inhibiting miR-125b regulates the Wnt/ß-catenin pathway and EMT to suppress the proliferation and migration of MDA-MB-468 TNBC cells.

A novel dominant mutation in the SOX10 gene in a Chinese family with Waardenburg syndrome type II.

Waardenburg syndrome type 2 (WS2) is a rare genetic disorder, characterized by bright blue eyes, moderate to profound hearing loss and pigmental abnormalities of the hair and skin. Between 10 and 20 mutations in the SRY­box 10 (SOX10) gene were previously identified to be associated with WS2. The present study aimed to identify the genetic causes of WS2 in a Chinese family. Clinical and molecular analyses were performed to genetically characterize a Chinese family with two cases of WS2. The clinical data of the proband were collected using a questionnaire. The genomic DNA was extracted from peripheral blood samples of each individual in the family, and 168 candidate genes associated with hearing loss were sequenced using the Illumina HiSeq 2000 and confirmed by Sanger sequencing. A heterozygous nonsense mutation [substitution; position 127; cytosine to thymine (c.127C>T)] was identified in exon 2 of SOX10 (transcript ID: NM_006941.3) in the proband and the mother; however, not in other family members or healthy controls. The novel nonsense heterozygous mutation may cause the replacement of codon 43 [arginine (Arg)] with a stop codon (Arg43stop), leading to premature termination of protein translation. The novel nonsense heterozygous mutation c.127C>T in the SOX10 gene was considered to be the cause of WS2 in the family. This mutation has not been identified in any databases, to the best of the authors' knowledge, including The Single Nucleotide Polymorphism Database, The Human Gene Mutation Database, 1000 Genomes Project and ClinVar and Exome Sequencing Project v. 6500.

Isoalantolactone suppresses LPS-induced inflammation by inhibiting TRAF6 ubiquitination and alleviates acute lung injury.

Isoalantolactone (IAL) is a sesquiterpene lactone extracted from roots of Inula helenium L and has shown anti-inflammatory effects. In this study we investigated the therapeutic effects of IAL on acute lung injury (ALI) and elucidated the mechanisms underlying its anti-inflammation potential in vitro and in vivo. Treatment with lipopolysaccharide (LPS, 100 ng/mL) drastically stimulated production of inflammatory mediators such as NO, TNF-α, IL-1ß, and IL-6 in mouse bone marrow-derived macrophages (BMDMs), which was dose-dependently suppressed by pretreatment with IAL (2.5, 5, 10, 20 µM). We further revealed that IAL suppressed LPS-induced NF-κB, ERK, and Akt activation. Moreover, the downregulation of non-degradable K63-linked polyubiquitination of TRAF6, an upstream transcription factor of NF-κB, contributed to the anti-inflammatory effects of IAL. ALI was induced in mice by intratracheal injection of LPS (5 mg/kg). Administration of IAL (20 mg/kg, i.p.) significantly suppressed pulmonary pathological changes, neutrophil infiltration, pulmonary permeability, and pro-inflammatory cytokine expression. Our results demonstrate that IAL is a potential therapeutic reagent against inflammation and ALI.

Waardenburg syndrome type II in a Chinese patient caused by a novel nonsense mutation in the SOX10 gene.

OBJECTIVE: Waardenburg syndrome is a congenital genetic disorder. It is the most common type of syndromic hearing impairment with highly genetic heterogeneity and proved to be related by 6 genes as follows: PAX3, MITF, SNAI2, EDN3, EDNRB and SOX10. This article aims to identify the genetic causes of a Chinese WS child patient. METHODS: A Chinese WS child was collected for clinical data collection by questionnaire survey. DNA samples of proband and his parents were extracted from peripheral blood samples. Six candidate genes were sequenced by the Trusight One sequencing panel on the illumina NextSeq 500 platform. RESULTS: A novel nonsense heterozygous mutation was found in the coding region of exon 2 in the SOX10 gene of proband. The novel nonsense heterozygous mutation could cause the replacement of the 55th lysine codon by stop codon (484T > C, C142R) and further more possibly cause terminating the protein translation in advance. However, both proband's parents had no mutation of genes above mentioned. CONCLUSION: The gene mutation of SOX10 [NM_006941.3 c.163A > T] is a novel nonsense mutation. No record of this mutation has been found in dbSNP, HGMD, 1000 Genomes Project, ClinVar and ESP6500 databases. It meets the condition of PS2 of strong evidence in 2015 ACMG Standards and Guidelines.

Bone morphogenetic protein-4 induces upregulation of Cav3.1 Ca²âº channels in HL-1 atrial myocytes.

Cardiac T-type Ca(2+) channels are reexpressed in atrial and ventricular myocytes under various pathological conditions such as post-myocardial infarction, hypertrophy, and heart failure, but relatively little is known about the mechanisms. Our previous study found that bone morphogenetic protein-4 (BMP4) was reexpressed in pathological cardiac hypertrophy models and BMP4-mediated cardiomyocyte hypertrophy. We hypothesized that BMP4 could upregulate cardiac T-type Ca(2+) channels in HL-1 atrial myocytes. The T-type Ca(2+) currents were recorded by using the patch-clamp technique, and the expressions of Cav3.1 and Cav3.2 were measured by real-time PCR method in HL-1 cells. BMP4 and Cav3.1 mRNA expressions increased in the left atrium from the pressure overload-induced hypertrophy of mice hearts. BMP4 treatment for 48 h induced increase of Cav3.1 but not Cav3.2 mRNA expression in HL-1 cells, and the increase was inhibited by BMP4 inhibitor noggin. Acute treatment with BMP4 did not affect T-type Ca(2+) currents, but chronic treatment (48 h) significantly increased the amplitude of T-type Ca(2+) currents in HL-1 cells. Chronic treatment with BMP4 induced upregulation of NADPH oxidase-4 (NOX4), increase of reactive oxygen species (ROS) level, and activation of mitogen-activated protein kinase (MAPK)-activated protein kinases c-jun N-terminal kinases (JNK) and p38. BMP4-induced upregulation of Cav3.1 mRNA was inhibited by NADPH oxidase inhibitor apocynin, the radical scavenger tempol, JNK inhibitor SP600125, and p38 inhibitor SB203580. In conclusion, BMP4 induces upregulation of Cav3.1 Ca(2+) channels and T-type Ca(2+) currents in HL-1 atrial myocytes through ROS/MAPK pathways.

Copper induces vasorelaxation and antagonizes noradrenaline-induced vasoconstriction in rat mesenteric artery.

BACKGROUND/AIMS: Copper is an essential trace element for normal cellular function and contributes to critical physiological or pathological processes. The aim of the study was to investigate the effects of copper on vascular tone of rat mesenteric artery and compare the effects of copper on noradrenaline (NA) and high K(+) induced vasoconstriction. METHODS: The rat mesenteric arteries were isolated and the vessel tone was measured by using multi wire myograph system in vitro. Blood pressure of carotid artery in rabbits was measured by using physiological data acquisition and analysis system in vivo. RESULTS: Copper dose-dependently blunted NA-induced vasoconstriction of rat mesenteric artery. Copper-induced vasorelaxation was inhibited when the vessels were pretreated with NG-nitro-L-arginine methyl ester (L-NAME). Copper did not blunt high K(+)-induced vasoconstriction. Copper preincubation inhibited NA-evoked vasoconstriction and the inhibition was not affected by the presence of L-NAME. Copper preincubation showed no effect on high K(+)-evoked vasoconstriction. Copper chelator diethyldithiocarbamate trihydrate (DTC) antagonized the vasoactivity induced by copper in rat mesenteric artery. In vivo experiments showed that copper injection (iv) significantly decreased blood pressure of rabbits and NA or DTC injection (iv) did not rescue the copper-induced hypotension and animal death. CONCLUSION: Copper blunted NA but not high K(+)-induced vasoconstriction of rat mesenteric artery. The acute effect of copper on NA-induced vasoconstriction was depended on nitric oxide (NO), but the effect of copper pretreatment on NA-induced vasoconstriction was independed on NO, suggesting that copper affected NA-induced vasoconstriction by two distinct mechanisms.

[Preparation and properties of P-type Cd1-xZn(x)Te thin films].

Cd1-xZnxTe:Cu Thin films were prepared by co-evaporation method. X-ray Fluorescence Spectrometry (XRF), scanning electron microscope(SEM), UV-Vis transmission spectra, thermal probe, four-probe method, step profiler and X-ray diffractometer (XRD) were used to investigate the composition, structure, morphology, optical and electrical properties of Cd1-x ZnxTe:Cu thin films with different doping concentration. The results show that the resistivity of 10% copper doped Cd1-x ZnxTe films increased several magnitude and the conductive type changed from p-type to n-type after annealing. The 20% cu-doped Cdl, Zn,Te films had not obvious change in conductive type and electrical resistivity after annealing and they exhibit good surface morphology. The transmissivity of 30% cu-doped Cd1-x, ZnxTe films decreased seriously below 10% after annealing, which indicate that they are not suitable to be the top cell materials in tandem structure. The 20% and 30% cu-doped Cd1-x Zn, Te films were both p-type conductivity.

[Frequency distribution and antibiotic resistance of pathogens from the cerebrospinal fluid of 116 children with bacterial meningitis].

OBJECTIVE: To determine the frequency distribution and antibiotic resistance of pathogens isolated from the cerebrospinal fluid samples of children with bacterial meningitis (BM) and to provide a basis for the timely and effective treatment of childhood BM. METHODS: Retrospective analysis was performed on pathogens isolated from 5097 cerebrospinal fluid samples collected from children in Kunming Children's Hospital between January 2008 and June 2012, as well as drug sensitivity test results. Kirby-Bauer antibiotic testing was used to analyze the sensitivity of these pathogens to commonly used antibiotics. RESULTS: A total of 116 pathogen strains were detected from the 5097 cerebrospinal fluid samples, including 77 (66.4%) Gram-positive strains, 30 (25.9%) Gram-negative strains, and 9 (7.8%) fungal strains, with a positive rate of 2.28%. The six most frequently isolated pathogens were Staphylococcus epidermidis (32 strains, 27.6%), Streptococcus pneumoniae (15 strains, 12.9%), Escherichia coli (15 strains, 12.9%), Staphylococcus haemolyticus (9 strains, 7.8%), Cryptococcus neoformans (8 strains, 6.9%) and Staphylococcus aureus (6 strains, 5.2%). Coagulase-negative staphylococci was the predominant pathogen in neonates and young infants with BM, and its sensitivity rates to penicillin, erythromycin and clindamycin were lower than 40%. Streptococcus pneumoniae had a penicillin sensitivity rate of 13.4%, while sensitivity rates to erythromycin and clindamycin reached 60.0%. No Staphylococcus and Streptococcus pneumoniae pathogens resistant to vancomycin were found. Gram-negative bacilli had relatively high sensitivity rates to imipenem, meropenem, cefoperazone/sulbactam and cefepime. CONCLUSIONS: Gram-positive cocci are the predominant pathogens for childhood BM over the past five years. The detected pathogens develop high resistance to commonly used antibiotics. To prevent misdiagnosis, careful attention should be paid to BM caused by Cryptococcus neoformans.

[RNA interference-mediated inhibition of survivin expression in Hela cell line by siRNA expression vector targeting survivin gene].

OBJECTIVE: To prepare small interfering RNA (siRNA) targeting survivin for inhibition of endogenous survivin gene expression in Hela cell line and evaluate its effect on promoting Hela cell apoptosis. METHODS: The recombinant plasmid pshRNA-survivin-1 and pshRNA-survivin-2 were constructed and transfected into Hela cells, in which the expression level of survivin was determined by immunofluorescence staining and survivin gene transcription detected by semi-quantitative RT-PCR. RESULTS: Introduction of the plasmids pshRNA-survivin-1 and pshRNA-survivin-2 into Hela cells resulted in efficient and specific inhibition of survivin expression as demonstrated by immunofluorescence staining. Semi-quantitative RT-PCR showed that mRNA transcription of survivin gene was reduced. In contrast, the control plasmid did not exhibit any inhibitory effect on the protein expression and mRNA transcription of survivin gene. PI-Annexin V staining indicated an apoptosis rate of the transfected Hela cells of (36.02-/+2.12)% (P<0.01) and (35.29-/+2.02)% (P<0.01), respectively. CONCLUSION: The prepared siRNA targeting survivin gene is capable of inducing marked inhibitions of survivin protein expression and RNA transcription and significant enhancement of apoptosis in Hela cells, which shed light on a new strategy in gene silence therapy targeting survivin.

High-level expression and purification of recombinant huGM-CSF (9-127)/IL-6 (29-184) fusion protein in Escherichia coil.

As HuGM-CSF and huIL-6 seem to have synergistic and complementary actions, researchers have proposed that fusion proteins incorporating these two cytokines could show increased biological activity, especially in terms of hematopoietic function. Here, we sought to obtain a functional GM-CSF/IL-6 fusion protein and to investigate its biological activities in vitro. A novel construct encoding a fusion protein of huGM-CSF (9-127) and IL-6 (29-184) was generated in the pBV220 expression vector by step-by-step cloning. Amino acids 1-8 of huGM-CSF and amino acids 1-28 of huIL-6 were deleted by PCR. The mutant huGM-CSF (9-127) and huIL-6 (29-184) cDNAs were linked via a linker sequence encoding 15 amino acid residues (G-G-S-G-S)3. Direct sequencing was used to confirm the validity of the desired construct, and the fusion protein was expressed in Escherichia coli host strain BL21 (DE3) in the form of inclusion bodies (IBs). The expression level was more than 25% of the total cell lysate, and a novel purification and refolding strategy was used to isolate the fusion protein product. Inclusion bodies were purified by Q Sepharose H.P. ion exchange in 8 mol/L urea, followed by in situ refolding by Sephacryl S-200. The renatured fusion proteins were obtained at a purity of >95%, and the strategy of refolding on the gel filtration column was found to be efficient, with a relative refolding rate of 80%. This entire refolding and purification procedure could be performed within one day and may prove applicable to large-scale purification and refolding of recombinant proteins from IBs in E. coli. This new method was used to obtain huGM-CSF (9-127)/IL-6 (29-184) fusion protein with high purity and biological activity. MTT assays in TF-1 and B9 cell lines showed that the specific biological activity of huGM-CSF was 1.14+/-0.10 x 10(8) U/mg, and that for huIL-6 was 1.89+/-0.11 x 10(7) U/mg. The fusion protein exhibited enhanced huGM-CSF, but similar huIL-6 biological activities compared with those of either GM-CSF or IL-6 alone. This suggests that our novel huGM-CSF (9-127)/IL-6 (29-184) fusion protein may hold future promise as a therapeutic agent.