[Expert consensus on standardized clinical applications of minimally invasive tooth extraction techniques].

Tooth extraction is a common and widely employed therapeutic procedure in oral and maxillofacial surgery. Minimally invasive tooth extraction can reduce both physical and psychological trauma to the patients, and is widely recommended as a first-line clinical treatment. But currently no guidelines or consensus has been available to provide a systematic introduction of minimally invasive tooth extraction to guide the clinical practices. To address this issue, this consensus, based on a comprehensive literature review and clinical experiences of experts, systematically summarizes the indications, target patients, and contraindications of minimally invasive tooth extraction, the overall workflow of this procedure (preoperative preparation, surgical steps, postoperative management, postoperative instructions, medications, and follow-up), and its common postoperative complications to provide a comprehensive guidance for clinical application of this technique.

Rapid creation of CENH3-mediated haploid induction lines using a cytosine base editor (CBE).

Haploid induction (HI) can create true-breeding lines in a single generation, which can significantly accelerates the breeding process. In recent years, scientists have developed a variety of new techniques to induce haploids through manipulation of CENH3, a variant of the centromere-specific histone H3. One alternative approach is based on CENH3 point mutations derived from EMS/TILLING, which is not lethal and yet is responsible for inducing haploids. However, most residues have been obtained by EMS mutagenesis over a long period of time. Recently, a new approach called 'base editing' was developed for plants. Here, we report a new method that uses a cytosine base editor (CBE) to create a point mutation of CENH3 as a haploid induction line, which substitutes adenine (A) for guanine (G). As proof of the extreme simplicity of this approach to create haploid-induced lines, we identified an L130F substitution within the histone fold domain in Arabidopsis thaliana. Subsequently, we tested the haploid-inducing potential of homozygous L130F plants by pollinating them with Col-0, and obtained 2.9% paternal haploid plants. In brief, our innovative technology provides a new perspective for the promotion of CENH3-mediated haploid induction in crops, and also provides a variety of options for breeders. Such conserved point mutations as L130F could be developed into a general instrument for haploid induction in a wide range of plant species. Extending these systems would represent a major advance over haploid production.

The three-dimensional evaluation of positional change in mandibular condyle after intraoral vertical ramus osteotomy.

OBJECTIVES: The purpose of this study was to compare the changes of the condylar axis, the anteroposterior condylar position relative to the glenoid fossa, after intraoral vertical ramus osteotomy (IVRO). STUDY DESIGN: 21 patients diagnosed as skeletal class III malocclusion underwent IVRO and were followed according to the authors' postoperative management regimen. The three-dimensional positions of the condyles were evaluated by cone-beam computerized tomography (CBCT) at pre-op, post-op, and at follow-up. CBCT images were referenced to assess the condylar axis change and the anteroposterior condylar position in the glenoid fossa. A repeated-measures analysis of variance (P<0.05) also was performed. RESULTS: After surgery, both the axial condylar angles and the anteroposterior condylar position were significantly different (P<0.05). The coronal condylar axis rotated outwardly. The anteroposterior condylar position in the glenoid fossa had moved from the concentric to the anterior position. But the condyle changes between post-op and follow-up (P>0.05) were insignificant. CONCLUSIONS: With postoperative intermaxillary elastic traction, the condyles changed their positions physiologically for newly established jaw movement after IVRO.

Characterization of Complete Genome Sequences of a Porcine Endogenous Retrovirus Isolated From China Bama Minipig Reveals an Evolutionary Time Earlier Than That of Isolates From European Minipigs.

BACKGROUND: A porcine endogenous retroviruses (PERV) isolate, PERV-A-BM, was isolated from a Guangxi Bama minipig in China. METHODS: To understand its genetic variation and evolution, the complete PERV-A-BM genome sequences were determined and compared with isolates from different Sus scrofa breeds and porcine cell lines. A total of 69 nucleotide substitutions were found in the full-length genome, including 26 non-synonymous mutations. RESULTS: Phylogenetic trees based on the complete genome sequence as well as the gag, pol, and env gene sequences from 21 PERV isolates demonstrated that the PERV-A-BM was closely related to the EF133960 isolate from Chinese Wuzhishan miniature pigs inbred in Hainan, China, and distantly related to strains isolated from European-born pigs. CONCLUSIONS: The estimation of age in the proviral PERV-A-BM integrating into the host genome reveals that the age of PERV-A-BM is at least 8.3 × 10(6) years, an evolutionary time earlier than that of isolates from European-born pigs.

Isolation and analysis of α-expansin genes in the tree Anthocephalus chinensis (Rubiaceae).

Expansins are cell wall-associated proteins that induce wall extension and relax stress by disrupting noncovalent bonds between cellulose microfibrils and cross-linking glycan chains, thereby promoting wall creep. Anthocephalus chinensis is a very fast-growing economically important tree found mainly in South Asia. Sixteen cDNAs, designated AcEXPA1 to AcEXPA16 (GenBank accession Nos. FJ417847, JF922686-JF922700) with corresponding genomic DNA sequences (GenBank accession Nos. GQ228823, JF922701-JF922715), were isolated by amplifying conserved domain binding with genomic walking and RACE techniques from four differential growth tissues in A. chinensis. These α-expansin homologues were highly conserved in size and sequence; they had the same sequence structures as an N-terminal signal peptide, three exons and two introns. Their amino acid alignment showed that A. chinensis expansin genes are divided into three subgroups: A, B and C. This study is the first report on expansin genes from A. chinensis. It will be used for a tissue-specific expression model and for studying the relationship between expansin genes, growth rate and wood quality of the xylem in this fast-growing tree.

Shear-induced changes in endothelin-1 secretion of microvascular endothelial cells.

Human glomerular microvascular endothelial cell (HGMEC) culture monolayers were maintained in static culture as controls or subjected to steady laminar shear stress of 0.5, 1.0, or 1.5 N/m2. Over 25 h of shear, the cumulative secretion of ET-1 was 705.4 pg/cm2 in the control, 820.7 pg/cm2 at 0.5 N/m2, 1063.2 pg/cm2 at 1.0 N/m2, and 644.7 pg/cm2 at 1.5 N/m2. The average ET-1 secretion rate for the HGMEC monolayers exposed to 0.5, 1.0, or 1.5 N/m2 of shear stress was 32.83 +/- 2.01 pg/cm2 x h, 42.53 +/- 3.74 pg/cm2 x h, and 25.79 +/- 1.29 pg/cm2 x h, respectively. The average ET-1 secretion rate of the static controls was 28.22 +/- 3.11 pg/cm2 x h. The results showed that low shear stress (0.5 N/m2) elevated and high shear stress (1.5 N/m2) suppressed secretion of ET-1, while an intermediate level of shear stress (1.0 N/m2) led to the maximum secretion of ET-1, and furthermore, ET-1 secretion varied with the duration of shear in a nonlinear fashion, and the logistic equations may be used to describe relationship between the duration of shear and the ET-1 secretion. The major secretion period of ET-1 occurred between 5.3 and 22.3 h, with the peak secretion rate occurring at approximately 10.7-15.2 h. Our findings showed also that the major secretion period and peak secretion rate of HGMECs varied with the level of shear stress. Thus, the response of cultured human microvascular endothelial cells to shear stress differed from that of large-vessel endothelial cell cultures in terms of ET-1 secretion. In addition to the level of shear stress, the duration of shear is an important determinant in ET-1 secretion. Consequently, the heterogeneity of vascular endothelial cells and the duration of shear should both be considered in future research on the secretion of vascular endothelial cell cultures.

Blockade of U50488H on potassium currents of acutely isolated mouse hippocampal CA3 pyramidal neurons.

The actions of the opioid agonist U50488H on IA and IK were examined in acutely isolated mouse hippocampal CA3 pyramidal neurons using the whole-cell patch clamp technique. U50488H caused a concentration dependent, rapidly developing and reversible inhibition of voltage-activated IA and IK. The inhibitory actions were still observed in the presence of 30 microM naloxone or 5 microM nor-binaltorphimine dihydrochloride. The IC50 values for the blockade of IA and IK were calculated as 20.1.9 and 3.7 microM, respectively. In the presence of 3.3 microM U50488H, repetitive stimulation induced use-dependent inhibition of IA and IK. A 10 microM concentration of U50488H positively shifted the half-activation membrane potential of IA by +11 mV, but negatively shifted IK by -14 mV. These results demonstrate that U50488H can directly inhibit neuronal IA and IK without involvement of the activation of kappa-opioid receptors.

[Lymphocyte subset and its apoptosis in chronic hepatitis C].

OBJECTIVE: To explore the autoimmune pathogenesis induced by hepatitis C virus. METHODS: Serum anti-GOR and peripheral blood lymphocyte subset and its apoptosis rate after activated by Pokeweed mitogen (pwm) in vitro were measured by enzyme-linked immunosorbent assay and flow cytometry, respectively. Eighteen individuals with chronic hepatitis C and 16 healthy controls were observed. RESULTS: The positive rates of serum anti-GOR (66.7%) and ANA (44.4%) were significantly higher in chronic hepatitis C than normal controls (chi(2)=26.86, chi(2)=9.30, P<0.005). The apoptosis percentage of PBMCs and CD3(+)T cell was elevated in individuals with chronic hepatitis C when compared with normal controls (t=2.44, P<0.05). However, the apoptosis percentage of CD4(+)T and CD19(+)B cells in PBMCs was significantly decreased in patients with anti-GOR positive compared to anti-GOR negative (t=3.17, P<0.01; t=2.294, P<0.05). Similarly, the percentage of CD4(+)CD8(+) T cells in anti-GOR positive patients was increased and CD3(+)/CD4(+) was decreased (t=2. 18, P<0.05) compared to anti-GOR negative (t=2.44, P<0.05; t=2.18, P<0.05). CONCLUSION: autoimmune response exists in chronic hepatitis C patients. There is an imbalance of lymphocyte subset and its apoptosis, which may be one of the important reasons for the mechanism of autoimmune pathogenesis of chronic hepatitis C.

Secretory response of endothelin-1 in cultured human glomerular microvascular endothelial cells to shear stress.

The shear-induced secretory response of endothelin-1 (ET-1) by human microvascular endothelial cells was studied using paired human glomerular microvascular endothelial cell (HGMEC) cultured monolayers exposed to steady-state laminar shear stress for up to 10 hours. The first cell monolayer was subjected to a shear stress of 0.65 N m-2 and the second, 1.3 N m-2. ET-1 secretion was determined by radioimmunoassay. Over 10 hours of shear, the total cumulative secretion of ET-1 was 237.4 pg/cm2 for the monolayer exposed to 1.3 N m-2 and 143.6 pg/cm2 for the monolayer exposed to 0.65 N m-2. The average ET-1 secretion rate was 20.90 +/- 2.15 and 12.45 +/- 1.05 pg/cm2.h at 0.65 N m-2 and 1.3 N m-2, respectively. The results showed that ET-1 secretion varied with the time of shear in a nonlinear fashion. Although the level of shear stress affected the absolute value of ET-1 cumulative secretion and secretion rate, the major secretion period for both monolayers occurred between 2.0 and 8.0 hours, with the peak secretion rate occurring at approximately 5 hours. Thus, the response of cultured human microvascular endothelial cells to shear stress differed from that of large vessel endothelial cell cultures in terms of ET-1 secretion. In addition to the level of shear stress, the time of shear was also an important determinant of ET-1 secretion. Consequently, the heterogeneity of vascular endothelial cells and the time of shear should both be considered in future research on the secretion of vascular endothelial cell cultures.

[Polymerase chain reaction applied for detection of Toxoplasma gondii in lymph nodes].

In order to investigate the morbidity of toxoplasmic lymphadenitis, polymerase chain reaction (PCR) was used to detect DNA of Toxoplasma gondii within lymph nodes in 3 groups of 120 patients with different diseases. After extracting the DNA of each sample, PCR was employed to amplify toxoplasma DNA. The results showed that the amplification product of 210 bp was confirmed in 7 patients: 3 cases of Hodgkin's disease (HD), 2 cases of non-Hodgkin's lymphoma (NHL) and 2 cases of chronic lymphadenitis (CL). Each PCR product was then subjected to Southern blot hybridization. Besides the 7 cases proved by PCR, 1 case of CL was found positive. The positive percentages of HD, NHL and CL were 9.38% (3/32), 4.88% (2/41), and 6.38% (3/47), respectively. The total positive rate was 6.67% (8/120).

[Detection of Toxoplasma gondii DNA in the autopsy cases of abnormal birth and teratosis by polymerase chain reaction].

Toxoplasma gondii DNA in the autopsy tissues of 72 cases of the premature, stillbirth and congenital malformation was detected using polymerase chain reaction (PCR). The specific amplified products were found in 9 cases, i.e. one case of premature, 3 cases of stillbirth, one case of hydrocephalus and 4 cases of other teratosis. The positive rate was 12.5%. Ten control samples were negative. The results showed that Toxoplasma gondii infection was present in the disease cases. The finding indicates that the infection of Toxoplasma gondii may be one of the main causes of the abnormal birth and the congenital teratosis.

[Serum type IV collagen and laminin in patients with chronic hepatitis and its clinical significance].

Serum levels of laminin and type IV collagen of 188 patients with different types of viral hepatitis were determined by RIA. Thirty-five blood donors were served as normal control. The results showed that: (1) higher levels of type IV collagen was found in patients with severe chronic hepatitis, post-hepatitis cirrhosis or subfulminant hepatitis; (2) the level of laminin was obviously increased in post-hepatitis cirrhosis and subfulminant hepatitis; (3) there was a positive correlation between the levels of type IV collagen and laminin as well as gamma globulin, and negatively correlated to serum albumin, no correlation with alanine aminotransferase was observed; (4) detecting rate of hepatic fibrosis was increased with combination of serum laminin and type IV collagen examination; (5) serum type IV collagen was more sensitive than that of serum laminin. The results suggest that determination of serum type IV collagen and laminin are useful in diagnosis of hepatic fibrosis, and combination of the two parameters is recommended.

[Clinical and laboratory studies with typhoid fever 178 patients].

One hundred and seventy-eight cases of typhoid patients were studied on clinical and bacteriological aspects. The main clinical findings were as follows: (1) Most of the cases had sustained fever (66.3%). (2) Gastroenterial symptoms developed as the disesase progressed. (3) Rose spots were found in 32.6% of them. (4) Liver and spleen were enlarged in 69.5% of the cases. (5) Blood eosinophil disappeared in most of the patients and leukopenia was noted in 94.3%. (6) There were toxic hepatitis (47.1%), toxic myocarditis (22.4%) and intestinal hemorrhage (19.7%) as complications. In the drug sensitivity test, the number of ampicillin-resistant and chloramphenicol-resistant strains of salmonella typhi was increased more than that seen 5 years ago (P < 0.05), however 100% of the strains were sensitive to amikacin, tobramycin, norflexacin, oflexacin and the third generation of the cephalosporin. For the time being, norflexacin and oflexacin were good and suitable drugs for the treatment of typhoid fever.