Comparison of the success rate of tracheal intubation between stylet and bougie with a hyperangulated videolaryngoscope: a randomised controlled trial

Hyperangulated videolaryngoscopes are known to increase the success rate of tracheal intubation in the setting of difficult airway management when used with a stylet or bougie. However, there is controversy over which adjunct is more useful. This randomised study aimed to compare first attempt tracheal intubation success rate between a stylet and bougie when using a hyperangulated videolaryngoscope. We recruited patients aged > 20 years who were scheduled for elective surgery under general anaesthesia and required tracheal intubation. We only included patients with factors predicting difficult tracheal intubation based on pre-anaesthesia airway evaluation. Tracheal intubation was attempted using a Glidescope® with either a stylet or bougie as an adjunct according to group assignment. Primary outcome was the success rate of the first tracheal intubation attempt, and secondary outcomes were success of second and third attempts; tracheal intubation time; and occurrence of sore throat, dysphagia or hoarseness. A total of 166 patients were included. The success rate of the first tracheal intubation attempt was significantly higher in patients allocated to the bougie group compared with those allocated to the stylet group (81/83 (98%) vs. 73/83 (88%), respectively; p = 0.032). The number of patients who needed two attempts was significantly lower in those allocated to the bougie group compared with those allocated to the stylet group (1/83 (1%) vs. 9/83 (11%), respectively; p = 0.018). Each group had one patient (1%) where tracheal intubation was achieved after a third attempt. There was no significant difference in the occurrence of sore throat, dysphagia and hoarseness between the two groups. When difficult tracheal intubation is anticipated and a hyperangulated videolaryngoscope is used, the success rate of the first attempt is higher when a bougie is used compared with a stylet.

Phylogeography of the desert scorpion illuminates a route out of Central Asia

A comprehensive understanding of phylogeography requires the integration of knowledge across different organisms, ecosystems, and geographic regions. However, a critical knowledge gap exists in the arid biota of the vast Asian drylands. To narrow this gap, here we test an "out-of-Central Asia" hypothesis for the desert scorpion Mesobuthus mongolicus by combining Bayesian phylogeographic reconstruction and ecological niche modeling. Phylogenetic analyses of one mitochondrial and three nuclear loci and molecular dating revealed that M. mongolicus represents a coherent lineage that diverged from its most closely related lineage in Central Asia about 1.36 Ma and underwent radiation ever since. Bayesian phylogeographic reconstruction indicated that the ancestral population dispersed from Central Asia gradually eastward to the Gobi region via the Junggar Basin, suggesting that the Junggar Basin has severed as a corridor for Quaternary faunal exchange between Central Asia and East Asia. Two major dispersal events occurred probably during interglacial periods (around 0.8 and 0.4 Ma, respectively) when climatic conditions were analogous to present-day status, under which the scorpion achieved its maximum distributional range. M. mongolicus underwent demographic expansion during the Last Glacial Maximum, although the predicted distributional areas were smaller than those at present and during the Last Interglacial. Development of desert ecosystems in northwest China incurred by intensified aridification might have opened up empty habitats that sustained population expansion. Our results extend the spatiotemporal dimensions of trans-Eurasia faunal exchange and suggest that species' adaptation is an important determinant of their phylogeographic and demographic responses to climate changes.

[Clinical features and management analysis of 11 cases of laryngocele]

Objective: To summarize clinical features and our experience of the diagnosis and treatment of laryngocele. Methods: Clinical data of 11 laryngocele patients in department of Otorhinolaryngology Head and Neck Surgery of the Second Affiliated Hospital of Shanxi Medical University from January 2012 to December 2021 were retrospectively reviewed, including 9 men and 2 women, aged from 12 to 75 years, with median age of 56 years. Electronic laryngoscope was performed in 10 of all patients, laryngeal CT in 10 and cervical color ultrasound in 5 before operation.All the operations were performed under general anesthesia, and the external cervical approach was used for external and combined laryngocele. The internal laryngocele was resected by low temperature plasma through transoral endoscopy. Patients were followed up regularly after operation to evaluate the effect. Clinical feature, types of lesions, imaging findings, surgical approaches and follow-up results were analyzed through descriptive statistical method. Results: Eleven laryngocele patients were divided into mixed type (n=6), internal type (n=4) and external type (n=1).Nine patients presented with hoarseness or dysphonia, 7 with cervical mass and 1 with airway obstruction. Surgical resections were done through external cervical approach (n=7)or transoral endoscopic approach (n=4). All the operations were successful and no complication occurred. All cases were followed up from 17 to 110 months. No recurrence was encountered. Conclusions: Laryngocele is a rare lesion with atypical clinical presentation. Preoperative imaging including CT scan and electronic laryngoscope is essential to evaluate the location, and extent of the lesion, and to make the surgical plan.Complete surgical excision is required. Surgical resection is the only effective method for the treatment of laryngocele.

Acupoint Thread Embedding Combined With Wenshen Bugu Decoction for the Treatment of Aromatase Inhibitor-Associated Musculoskeletal Symptom Among Postmenopausal Breast Cancer Patients: Study Protocol of a Randomized Controlled Trial

BACKGROUND

Aromatase inhibitors (AIs) are recommended as the preferred therapy for postmenopausal women with hormone receptor-positive (HR+) breast cancer. As a result, aromatase inhibitor-associated musculoskeletal symptom (AIMSS) have become a major problem leading to therapy discontinuation and decreased quality of life in patients receiving adjuvant AIs treatment. Multiple therapies have been attempted, but have yielded limited clinical results. This study will be performed to determine whether acupoint thread embedding (ATE) combined with Wenshen Bugu Decoction can effectively treat AIMSS, so as to improve the AIs medication compliance of postmenopausal breast cancer patients.

METHODS

This study will utilize a randomized, 2 parallel groups controlled trial design. A total of 128 eligible postmenopausal breast cancer women with AIMSS will be randomized to receive a 12-week treatment with Wenshen Bugu Decoction alone (control group) or in combination with ATE (treatment group) in a 1:1 ratio. The primary outcome will be the 12 week Brief Pain Inventory Worst Pain (BPI-WP) score. The secondary outcome measures will include response rate, Brief Pain Inventory-Short Form (BFI-SF), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Functional Assessment of Cancer Therapy-Endocrine Symptom (FACT-ES), Functional Assessment of Cancer Therapy-Breast (FACT-B), bone marrow density (BMD), blood markers of bone metabolite, Morisky medication adherence scale-8 (MMAS-8), credibility and expectancy, and survival outcomes.

DISCUSSION

This trial may provide clinical evidence that ATE combined with Wenshen Bugu Decoction can be beneficial for treating AIMSS among postmenopausal breast cancer survivors. Our findings will be helpful to enhance the quality of life and reduce the occurrence of AIs withdrawal.

[Clinical analysis of 12 cases of laryngeal neuroendocrine carcinoma]

Objective: To investigate the clinical and pathological features, treatments and prognosis of laryngeal neuroendocrine carcinoma (LNEC). Methods: We conducted the retrospective analysis of the clinical data of 12 patients with LNEC admitted to the Department of Otorhinolaryngology Head and Neck Surgery, Second Hospital of Shanxi Medical University from May 2014 to December 2021, including 9 males and 3 females, aged 50-77 years. There were 4 cases of typical carcinoid tumour (highly differentiated), 5 cases of atypical carcinoid tumour (moderately differentiated) and 3 cases of neuroendocrine small cell carcinoma (hypofractionated). The clinical features, diagnosis, treatment and prognosis of LNEC were analysed. Results: The clinical manifestations of LNEC varied according to the tumour type but did not correlate with the pathological types. The supraglottic type was characterized by sore throat, foreign body sensation in the pharynx, coughing, obstructive sensation when eating and choking on water. The treatments were determined according to the pathological types, lesion location and invasion scope. Of 12 patients 4 underwent horizontal partial laryngectomy plus elective lymphatic dissection plus postoperative radiotherapy/chemotherapy, 4 underwent vertical partial laryngectomy (3 of them with cervical lymphatic dissection), 3 underwent supported laryngoscopic plasma laryngectomy for laryngeal cancer, and 1 abandoned for treatment. With the follow-up of 8 -78 months, 5 patients were alive, 1 died from chemotherapy reactions, 3 died from other diseases, 1 died from lung metastasis, 1 died from lung infection and 1 was lost to follow-up. Conclusion: LNEC is clinically rare, the clinical manifestations are less specificity, diagnosis relies on pathological and immunohistochemical examinations, and treatment modalities and prognoses are closely related to the pathological subtypes of LNEC.

Characteristics of silicon nitride deposited by very high frequency (162 MHz)-plasma enhanced atomic layer deposition using bis(diethylamino)silane

Silicon nitrides, deposited by capacitively coupled plasma (CCP)-type plasma enhanced atomic layer deposition (PEALD), are generally applied to today's nanoscale semiconductor devices, and are currently being investigated in terms of their potential applications in the context of flexible displays, etc. During the PEALD process, 13.56 MHz rf power is generally employed for the generation of reactive gas plasma. In this study, the effects of a higher plasma generation frequency of 162 MHz on both plasma and silicon nitride film characteristics are investigated for the purpose of silicon nitride PEALD, using bis(diethylamino)silane (BDEAS) as the silicon precursor, and N₂ plasma as the reactant gas. The PEALD silicon nitride film deposited using the 162 MHz CCP exhibited improved film characteristics, such as reduced surface roughness, a lower carbon percentage, a higher N/Si ratio, a lower wet etch rate in a diluted HF solution, lower leakage current, and higher electric breakdown field, and more uniform step coverage of the silicon nitride film deposited in a high aspect ratio trench, as compared to silicon nitride PEALD using 13.56 MHz CCP. These improved PEALD silicon nitride film characteristics are believed to be related to the higher ion density, higher reactive gas dissociation, and lower ion bombardment energy to the substrate observed in N₂ plasma with a 162 MHz CCP.

Typical ulcerative colitis treated by herbs-partitioned moxibustion: A case report

BACKGROUND

Ulcerative colitis (UC), also known as chronic nonspecific UC, is an inflammatory bowel disease characterized by diffuse colonic mucosal inflammation. The incidence and prevalence of UC have risen markedly, and the disease seriously affects the quality of life of patients, and poses a great burden on the world health care infrastructure and economy.

CASE SUMMARY

We present a 60-year-old man who had ulcerative colitis for more than 10 years, with recurrent abdominal pain, bloody diarrhea with mucopurulent stool. The treatments with sulfasalazine, mesalazine, and traditional Chinese medicine were not effective, and herbs-partitioned moxibustion (HPM) was then applied at "Zhongwan" (RN12), "Tianshu"(ST25), and "Qihai" (RN6) once a day for about 30 min, 3 times per week, for 6 mo.His main clinical symptoms of abdominal pain, bloody diarrhea with mucopurulent stool gradually improved, and the mucosa had nearly healed, as observed under endoscopy by the 6th mo. The patient's condition was alleviated without relapsing during the subsequent 3-mo follow-up period. HPM showed a significant effect in the treatment of ulcerative colitis in this case, and the effect would help the patient to maintain remission for at least 3 mo.

CONCLUSION

A series of symptoms of this UC patient significantly improved with the treatment of HPM.

[Endoscopic transpterygoid intervention for lesions of lateral recess of sphenoid sinus in 4 cases(with literature review) ]

Objective: To investigate the anatomy and application of endoscopic transpterygoid intervention in lesions of lateral recess of sphenoid sinus(LRSS). Method: Four hospitalized patients with lesions of LRSS were studied. The clinical presentations included spontaneous cerebrospinal fuild(CSF) leakage in 2 cases, meningoencephaolece complicated CSF leakage in 1 case and chronic invasive fungal sphenoid sinusitis invading the base of the middle fossa in 1 case. Endoscopic transpterygoid intervention and repairment of skull base defects were performed under general anesthesia. Result: he operations were successfu1 in all patients. One patient suffered from postoperative palatal hypesthesia and all the symptoms mentioned above relieved gradually 6 months after operation. No recurrence was found during the follow-up ranging from 6 to 45 months(mean follow-up period,22.75 months).Conclusion: Endoscopic transpterygoid intervention in lesions of LRSS is a minimally invasive and safe surgical approach.

[Expand prelacrimal recess-maxillary ainus approach for inferior orbital walls fracture treatment]

Objective: To investigate the surgical technique and curative effect of transnasal endoscopic anterior lacrimal approach for the treatment of sacral wall fractures. Method: Retrospective clinical analysis of 5 patients with inferior orbital walls fracture treated by expanding prelacrimal recess-maxillary ainus under nasal endoscope was studied, and the surgical method and its efficacy were annalyzed. Result: After 1 year of follow-up,4 patients' diplopia symptom disappeared, and 1 patient's diplopia symptom was significantly relieved compared with preoperation, the range of eye movement was normal and enophthalmos were totally corrected.Conclusion: Expanding prelacrimal recess-maxillary ainus approach for the treatment of the inferior orbital walls fracture is an effective surgical method.It has the characteristics of less trauma,no incision on the face, clear visual field and wide space of operation, which is worthy of clinical promotion.

Stages of pregnancy and weaning influence the gut microbiota diversity and function in sows

Aims

The gut microbiota is believed to play important roles in the health of pregnant mammals, including their nutrient metabolism, immune programming and metabolic regulation. However, until recently, the shifts in gut microbiota composition and faecal and blood metabolic activity during different stages of pregnancy had not been investigated.

Methods and Results

We investigated the shifts in backfat thickness, plasma and faecal metabolites and gut microbiota on days 30, 60, 90 and 110 of pregnancy and on day 21 after parturition (weaning) in sows. The backfat thickness of sows did not significantly differ among the different stages of pregnancy. The plasma concentrations of lipid metabolites, including triacylglycerol (TG), total cholesterol, high‐density lipoprotein‐cholesterol, low‐density lipoprotein‐cholesterol and calcium were reduced (P < 0·05) during pregnancy. In addition, the concentration of these metabolites, except TG, reached their maximum at the time of weaning. We also found that Tenericutes, Fibrobacteres and Cyanobacteria varied significantly according to the stages of pregnancy in sows (P < 0·05). Most of the genera, such as Clostridiales, Desulfovibrio, Mogibacteriaceae and Prevotella, increased (P < 0·05) with the progression of pregnancy and decreased (P < 0·05) at weaning. The alpha diversity values (i.e., Shannon diversity and observed species) of sow gut microbiota increased (P < 0·05) from pregnancy to weaning. Pregnancy stages also significantly influenced (P < 0·05) the community structure (beta diversity) of gut microbiota. The progression of pregnancy was associated with changes in lipid metabolism and several carbohydrate‐degradation bacteria (i.e., Prevotella, Succinivibrio, Bacteroides and Parabacteroides).

Conclusions

Although causal links between the measured parameters remain hypothetical, these findings suggest that the increased diversity and concentration of beneficial gut microbes are associated with the metabolism of pregnant sows.

Significance and Impact of the Study

Manipulation of the sow gut microbiota composition may potentially influence metabolism and health during pregnancy.

[Rhabditis axei found in urine routine examination: a case report]

Rhabditis axei is a free-living nematode, which can occasionally invade into humans through drinking and contacting wastewater. It is usually parasitic in the digestive and urinary systems, causing the disease of rhabditelliasis axei. This paper reports a case of R. axei infection found in the urine routine examination.

Switching to anastrozole plus goserelin vs continued tamoxifen for adjuvant therapy of premenopausal early-stage breast cancer: preliminary results from a randomized trial

Purpose

To assess the efficacy, safety, and quality-of-life impact of switching adjuvant treatment in hormone receptor-positive primary breast cancer patients who are still premenopausal after 2–3 years of tamoxifen therapy to anastrozole plus goserelin as compared with continuing tamoxifen over a total period of 5 years.

Patients and methods

Hormone receptor-positive, premenopausal, lymph node-positive, or tumor size ≥4 cm breast cancer patients who had received tamoxifen for 2–3 years were randomly assigned to continue tamoxifen treatment (TAM group) or switch to adjuvant anastrozole plus goserelin (ADD group) and continue treatment for another 2–3 years (total treatment duration 5 years). Endpoints evaluated were adverse events (AEs), changes in bone mineral density, quality of life, and disease-free survival-related events.

Results

A total of 62 patients (33 in the ADD group and 29 in the TAM group) were evaluated. Grade 3–4 drug-related AEs occurred in five patients (15.2%) in the ADD group vs none in the TAM group. In the ADD group, arthralgias were the most common AEs (5/33 patients; 15.2%), and three patients in this group were discontinued because of AEs. Treatment was temporarily suspended due to AEs in three patients (9.1%) in the ADD group and one patient (3.4%) in the TAM group. Compared with continuing TAM therapy, switching to anastrozole plus goserelin did not result in any worsening of bone mineral density or quality of life. During a median follow-up of 34 months, five patients (15.2%) in the ADD group had disease-free survival events vs four patients (13.8%) in the TAM group.

Conclusion

For early-stage breast cancer patients who remain premenopausal following 2–3 years of adjuvant tamoxifen therapy, switching to anastrozole plus goserelin therapy was safe with tolerable adverse effects. However, it did not show superior efficacy compared to remaining on tamoxifen treatment.

Trial Registration

ClinicalTrials.gov (identifier NCT01352091).

[A preliminary study of a modified transnasal endoscopic three step vidian neurectomy]

Objective:The aim of this study is to explore an improved trans-nasal endoscopic surgical approach for vidian neurectomy. Method:Ninety-one patients with nasal hyperreactive disease were collected, including 49 cases of allergic rhinitis and 42 cases of non allergic rhinitis. All sufferers enrolled in the study have treated with medicine, but the symptoms were not effectively controlled. Preoperative CT localization of the vidian canal was performed in each candidate. During the surgery a"Three-step" surgical approach were followed under endoscopic guidance in accordance with the operation procedures. Briefly, such a three-step procedure consists of the following, that is, a transnasal endoscopic sphenoidectomy through sphenoethmoidal recess as step one, with enlargement of the sinus ostium along the junction of the anterior wall and the floor of the sinus until the exposure of the vidian nerve canal toward the lateral wall of the sinus as step two. The last step was further exposure of the vidian nerve going through the canal and electric cautery preventing bleeding from the neurovascular bundle in the canal. Result:All patients were completed successfully with 100% preoperative CT location of the vidian canal in the CT scan and 100% intraoperative accurate exposure of the canal and therefore the cut of the vidian nerve. Conclusion:"Three-step" endoscopic resection of the vidian neurectomy is easy to master and repetitive with less injury.

[Analysis of clinical effect of unilateral vidian neurectomy following endoscopic trans-sphenoethmoidal recess approach for allergic rhinitis treatment]

Objective: To explore the clinical efficacy of unilateral vidian neurectomy following endoscopic trans-sphenoethmoidal recess approach in treating allergic rhinitis.Method: The clinical data of 80 patients with moderate-severe allergic rhinitis who underwent unilateral vidian neurectomy following endoscopic trans-sphenoethmoidal recess approach were reviewed retrospectively. Visual analogue scale(VAS) was used to assess total symptom scores and nasal symptoms including nasal itching, nasal sneezing, rhinorrhea and nasal congestion. The paired T test was used to compare the scores between surgical side and control side. Twenty-four patients with 3 years of follow-up were assessed by analysis of variance with comparison of means between multiple groups. Further comparison between any two means was performed by LSD-t test. Result: A total of 80 patients were followed up for one year, with 51 patients for two years and 24 patients for three years. Among 24 patients, total symptom scores and nasal symptoms (nasal itching, nasal sneezing, rhinorrhea and nasal congestion) at pre-operation, 1 year,2 year and 3 year after operation were compared between surgical side and control side. There was no significant difference by the paired T test(P>0.05),but there was statically significant by analysis of variance(P<0.05) .The analysis of LSD-t test showed significant differences between pre-operative time point and each of the three time points after operation (P<0.05). Conclusion:The unilateral vidian neurectomy following endoscopic trans-sphenoethmoidal recess approach is an safe and effective technique in the management of moderate severe allergic rhinitis,and unilateral surgery could relieve bilateral nasal symptoms.

Statistical measures of genetic differentiation of populations: Rationales, history and current states

Population differentiation is a fundamental process of evolution, and many evolutionary studies, such as population genetics, phylogeography and conservation biology, all require the inference of population differentiation. Recently, there has been a lot of debate over the validity of FST (and its analogue GST) as a measure for population genetic differentiation, notably since the proposal of the new index D in 2008. Although several papers reviewed or explored specific features of these statistical measures, a succinct account of this bewildering issue with an overall update appears to be desirable. This is the purpose of the present review. The available statistics generally fall into two categories, represented by FST and D, respectively. None of them is perfect in measuring population genetic differentiation. Nevertheless, they each have advantages and are valuable for current research. In practice, both indices should be calculated and a comparison of them can generate useful insights into the evolutionary processes that influence population differentiation. FST (GST) has some unique irreplaceable characteristics assuring its standing as the default measure for the foreseeable near future. Also, it will continue to serve as the standard for any alternative measures to contrast with. Instead of being anxious about making choice between these indices, one should pay due attention to the equilibrium status and the level of diversity (especially HS) of the populations, since they largely sway the power of a given statistic to address a specific question. We provide a multi-faceted comparative summary of the various statistics, which can serve as a basic reference for readers to guide their applications.

Polymorphisms in the MTHFR gene are associated with breast cancer risk and prognosis in a Chinese population

Breast cancer is the most common cancer affecting women in China and the world. Folate supplementation is proven to be effective in reducing the risk of breast cancer or improving its prognosis. Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme involved in folate metabolism and DNA synthesis. This study aims to examine whether single nucleotide polymorphisms (SNP) in the MTHFR gene are associated with risk and survival of breast cancer and serum folate levels in healthy controls. We genotyped nine tagging SNPs in the MTHFR gene in a case-control study, including 560 breast cancer cases and 560 healthy controls in China. We found that TT genotype of rs1801133 had significant increased risk of breast cancer [adjusted odds ratio (OR) = 1.60, 95 % confidence interval (CI) 1.12-2.28] compared with CC genotype, and CC genotype of rs9651118 conferred significant reduced risk of breast cancer (adjusted OR = 0.65, 95 % CI 0.45-0.95) compared to TT genotype. Haplotype analysis also showed that MTHFR CACCAA and AGTCAC haplotypes (rs12121543-rs13306553-rs9651118-rs1801133-rs4846048-rs1801131) had significant reduced risk of breast cancer (adjusted OR = 0.70, 95 % CI 0.58-0.86; adjusted OR = 0.57, 95 % CI 0.40-0.80) compared with CATTAA haplotype. Besides, MTHFR rs9651118 CC genotype was significantly associated with survival in breast cancer cases (adjusted hazard ratio (HR) = 0.63, 95 % CI 0.40-0.99). But none of the SNPs in the MTHFR gene was associated with serum folate level in healthy controls. These findings suggest that variants in the MTHFR gene may influence the risk and prognosis of breast cancer.

Impact of climate changes from Middle Miocene onwards on evolutionary diversification in Eurasia: insights from the mesobuthid scorpions

The aridification from Middle Miocene onwards has transformed the Asian interior into an arid environment, and the Pleistocene glacial-interglacial oscillations exerted further ecological impact. Therefore, both aridification and glaciation would have considerably influenced the evolution of many mid-latitude species in temperate Asia. Here, we tested this perspective by a phylogeographic study of the mesobuthid scorpions across temperate Asia using one mitochondrial and three nuclear genes. Concordant mitochondrial and nuclear gene trees were obtained, which are consistent with species tree inferred using a Bayesian approach. The age of the most recent common ancestor (MRCA) of all the studied scorpions was estimated to be 12.49 Ma (late Middle Miocene); Mesobuthus eupeus diverged from the clade composing Mesobuthus caucasicus and Mesobuthus martensii in early Late Miocene (10.21 Ma); M. martensii diverged from M. caucasicus at 5.53 Ma in Late Miocene. The estimated MRCA ages of M. martensii and the Chinese lineage of M. eupeus were 2.37 and 0.68 Ma, respectively. Central Asia was identified as the ancestral area for the lineage leading to M. martensii and M. caucasicus and the Chinese lineage of M. eupeus. The ancestral habitat of the genus Mesobuthus is likely to have been characterized by an arid environment; a shift towards more humid habitat occurred in the MRCA of M. martensii and a lineage of M. caucasicus, finally leading to the adaptation of M. martensii to humid environment. Our data strongly support the idea that the stepwise intensified aridifications from Mid-Miocene onwards drove the diversification of mesobuthid scorpions, and suggest that M. martensii and M. eupeus observed today in China originated from an ancestral lineage distributed in Central Asia. Both the colonization and the ensuing evolution of these species in East Asia appear to have been further moulded by Quaternary glaciations.

Unexpected relationships of substructured populations in Chinese Locusta migratoria

Background

Highly migratory species are usually expected to have minimal population substructure because strong gene flow has the effect of homogenizing genetic variation over geographical populations, counteracting random drift, selection and mutation. The migratory locust Locusta migratoria belongs to a monotypic genus, and is an infamous pest insect with exceptional migratory ability – with dispersal documented over a thousand kilometers. Its distributional area is greater than that of any other locust or grasshopper, occurring in practically all the temperate and tropical regions of the eastern hemisphere. Consequently, minimal population substructuring is expected. However, in marked contrast to its high dispersal ability, three geographical subspecies have been distinguished in China, with more than nine being biologically and morphologically identified in the world. Such subspecies status has been under considerable debate.

Results

By multilocus microsatellite genotyping analysis, we provide ample genetic evidence for strong population substructure in this highly migratory insect that conforms to geography. More importantly, our genetic data identified an unexpected cryptic subdivision and demonstrated a strong affiliation of the East China locusts to those in Northwest/Northern China. The migratory locusts in China formed three distinct groups, viz. (1) the Tibetan group, comprising locusts from Tibet and nearby West China high mountain regions; this is congruent with the previously recognized Tibetan subspecies, L. m. tibetensis; (2) the South China group, containing locusts from the Hainan islands; this corresponds to the Southeast Asia oriental tropical subspecies L. m. manilensis; (3) the North China group, including locusts from the Northwest and Northern China (the Asiatic subspecies L. m. migratoria), Central China and Eastern China regions. Therefore, the traditional concept on Locusta subspecies status established from Uvarov in 1930s needs to be revised. The three groups of locusts probably have separate evolutionary histories that were most likely linked to Quaternary glaciations events, and derived from different ancestral refugial populations following postglacial expansions.

Conclusion

The migratory locust populations in China have differentiated into three genetically distinct groups despite high dispersal capability. While this clarified long-standing suspicions on the subspecific diversification of this species in China, it also revealed that the locusts in the vast area of East China are not the oriental subspecies but the Asiatic subspecies, an unexpected substructuring pattern. The distribution pattern of the three locust groups in China may be primarily defined by adaptive differentiation coupled to Quaternary glaciations events. Our results are of general significance both for locust research and for phylogeographical study of flora and fauna in China, illustrating the potential importance of phylogeographical history in shaping the divergence and distribution patterns of widespread species with strong dispersal ability.

Haplotype reconstruction for scnp DNA: a consensus vote approach with extensive sequence data from populations of the migratory locust (Locusta migratoria)

Single copy nuclear polymorphic (scnp) DNA is potentially a powerful molecular marker for evolutionary studies of populations. However, a practical obstacle to its employment is the general problem of haplotype determination due to the common occurrence of heterozygosity in diploid organisms. We explore here a 'consensus vote' (CV) approach to this question, combining statistical haplotype reconstruction and experimental verification using as an example an indel-free scnp DNA marker from the flanking region of a microsatellite locus of the migratory locust. The raw data comprise 251-bp sequences from 526 locust individuals (1052 chromosomes), with 71 (28.3%) polymorphic nucleotide sites (including seven triallelic sites) and 141 distinct genotypes (with frequencies ranging from 0.2 to 25.5%). Six representative statistical haplotype reconstruction algorithms are employed in our CV approach, including one parsimony method, two expectation-maximization (EM) methods and three Bayesian methods. The phases of 116 ambiguous individuals inferred by this approach are verified by molecular cloning experiments. We demonstrate the effectiveness of the CV approach compared to inferences based on individual statistical algorithms. First, it has the unique power to partition the inferrals into a reliable group and an uncertain group, thereby allowing the identification of the inferrals with greater uncertainty (12.7% of the total sample in this case). This considerably reduces subsequent efforts of experimental verification. Second, this approach is capable of handling genotype data pooled from many geographical populations, thus tolerating heterogeneity of genetic diversity among populations. Third, the performance of the CV approach is not influenced by the number of heterozygous sites in the ambiguous genotypes. Therefore, the CV approach is potentially a reliable strategy for effective haplotype determination of nuclear DNA markers. Our results also show that rare variations and rare inferrals tend to be more vulnerable to inference error, and hence deserve extra surveillance.

In vivo expression of single-stranded DNA in mammalian cells with DNA enzyme sequences targeted to C-raf

The use of antisense oligodeoxynucleotides (AS-ODN) remains a viable method to downregulate selected gene function. However, limitations to the antisense approach remain, such as (1) difficulties in delivery of the AS-ODN into target tissues, (2) instability of AS-ODN in vivo, (3) uncertanties about the precise mode of action, and (4) toxic effects in animal and human studies. To circumvent some of these difficulties, we designed a vector set that directs the in vivo production of single-stranded DNA (ssDNA) of a desired target sequence with limited extraneous vector nucleotide sequences. One plasmid was designed to express Moloney murine leukemia virus (MoMuLV) reverse transcriptase (RT). Another expression plasmid contains the MoMuLV primer binding site at the 3'-end of its RNA transcript so that an ssDNA would be synthesized by RT when both plasmids are cotransfected into cells. To test this expression system, we constructed a plasmid set, pssXA/pssXB that produces ssRNA-cleaving DNA 10-23 enzyme (Santoro, S.W., and Joyce, G.F. [1997]. Proc. Natl. Acad. Sci. USA 37, 13330-13342). The DNA enzyme sequence was placed between two oligonucleotide arms that are complementary and able to specifically target C-raf kinase mRNA. These plasmids were transfected into the A549 lung carcinoma cell line. Reduced C-raf mRNA levels by up to 34%-36%, as determined by Northern blot analysis, were observed in the transfected cells. Our results demonstrate the feasibility of using this novel ssDNA expression system to generate any sequence of interest in vivo for antisense, RNA-cleavage DNA enzyme, or triplex-forming strategies.

The suppression effect of light rare earth elements on proliferation of two cancer cell lines

To study the suppression effect of light rare earth elements (RE) on proliferation of two cancer cell lines. Two cancer cell lines PAMC82 and K562 were used to examine their colony-forming ability in soft agar, microtubule structure, calmodulin levels and regulation of some gene expressions by Northern blot analysis with and without treatment by RE. The results showed that on soft agar culture the colony-forming ability of human gastric cancer cell line PAMC82 treated by RE chloride decreased and the PAMC82 cell microtubule abnormal structure became normal. The calmodulin (CaM) levels decreased in human leukemia cells (K562) treated with cerium chloride and neodymium chloride. The Northern blot analysis revealed marked up-regulation of p53, p16(MTS1), p21 (WAF1) gene expressions in PAMC82 cells treated with lanthanum chloride and cerium chloride, as compared to control PAMC82 cells. The light rare earth elements studied have certain suppression effects on proliferation of cancer cells. This effect might be related to the decrease of calmodulin and up-regulation of some gene expressions in cancer cells.