Brain development in newborns and infants after ECMO.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) not only significantly improves survival rates in severely ill neonates but also is associated with long-term neurodevelopmental issues. To systematically review the available literature on the neurodevelopmental outcomes of neonates and infants who have undergone ECMO treatment, with a focus on motor deficits, cognitive impairments, sensory impairments, and developmental delays. This review aims to understand the incidence, prevalence, and risk factors for these problems and to explore current nursing care and management strategies. DATA SOURCES: A comprehensive literature search was performed across PubMed, EMBASE, and Web of Science using a wide array of keywords and phrases pertaining to ECMO, neonates, infants, and various facets of neurodevelopment. The initial screening involved reviewing titles and abstracts to exclude irrelevant articles, followed by a full-text assessment of potentially relevant literature. The quality of each study was evaluated based on its research methodology and statistical analysis. Moreover, citation searches were conducted to identify potentially overlooked studies. Although the focus was primarily on neonatal ECMO, studies involving children and adults were also included due to the limited availability of neonate-specific literature. RESULTS: About 50% of neonates post-ECMO treatment exhibit varying degrees of brain injury, particularly in the frontal and temporoparietal white matter regions, often accompanied by neurological complications. Seizures occur in 18%-23% of neonates within the first 24 hours, and bleeding events occur in 27%-60% of ECMO procedures, with up to 33% potentially experiencing ischemic strokes. Although some studies suggest that ECMO may negatively impact hearing and visual development, other studies have found no significant differences; hence, the influence of ECMO remains unclear. In terms of cognitive, language, and intellectual development, ECMO treatment may be associated with potential developmental delays, including lower composite scores in cognitive and motor functions, as well as potential language and learning difficulties. These studies emphasize the importance of early detection and intervention of potential developmental issues in ECMO survivors, possibly necessitating the implementation of a multidisciplinary follow-up plan that includes regular neuromotor and psychological evaluations. Overall, further multicenter, large-sample, long-term follow-up studies are needed to determine the impact of ECMO on these developmental aspects. CONCLUSIONS: The impact of ECMO on an infant's nervous system still requires further investigation with larger sample sizes for validation. Fine-tuned management, comprehensive nursing care, appropriate patient selection, proactive monitoring, nutritional support, and early rehabilitation may potentially contribute to improving the long-term outcomes for these infants.

Mycolicibacterium arseniciresistens sp. nov., isolated from lead-zinc mine tailing, and reclassification of two Mycobacterium species as Mycolicibacterium palauense comb. nov. and Mycolicibacterium grossiae comb. nov.

A Gram-positive, acid-fast, aerobic, rapidly growing and non-motile strain was isolated from lead-zinc mine tailing sampled in Lanping, Yunnan province, Southwest China. 16S rRNA gene sequence analysis showed that the most closely related species of strain KC 300T was Mycolicibacterium litorale CGMCC 4.5724T (98.47 %). Additionally, phylogenomic and specific conserved signature indel analysis revealed that strain KC 300T should be a member of genus Mycolicibacterium, and Mycobacterium palauense CECT 8779T and Mycobacterium grossiae DSM 104744T should also members of genus Mycolicibacterium. The genome size of strain KC 300T was 6.2 Mb with an in silico DNA G+C content of 69.2 mol%. Chemotaxonomic characteristics of strain KC 300T were also consistent with the genus Mycolicibacterium. The average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity values, as well as phenotypic, physiological and biochemical characteristics, support that strain KC 300T represents a new species within the genus Mycolicibacterium, for which the name Mycolicibacterium arseniciresistens sp. nov. is proposed, with the type strain KC 300T (=CGMCC 1.19494T=JCM 35915T). In addition, we reclassified Mycobacterium palauense and Mycobacterium grossiae as Mycolicibacterium palauense comb. nov. and Mycolicibacterium grossiae comb. nov., respectively.

Monkeypox and the perinatal period: what does maternal-fetal medicine need to know?

BACKGROUND: After the global elimination of smallpox, monkeypox has become the most threatening orthopoxvirus to human health. Very few studies have been reported on pregnant women and newborns. In the case of monkeypox infection, the virus can cause serious adverse pregnancy events in women, which can lead to fetal or neonatal death. DATA SOURCES: We made a comprehensive review after an extensive literature search in the PubMed/Medline database and websites concerning smallpox and monkeypox. RESULTS: Two case reports reported a total of nine pregnant women, six of whom had fetal deaths. In the autopsy of a stillbirth, researchers found that the placenta was infected with monkeypox virus, but the mechanism of infection remains unclear. Smallpox vaccine should be administered to acutely exposed pregnant women and newborns. Several novel recombinant vaccinia immunogloblin (rVIG) and human-specific monoclonal antibodies are being developed for the prevention and treatment of monkeypox virus infection. After the fetus was delivered, the newborn should take a bath as soon as possible to remove the amniotic fluid and dirt from the body. The appropriate isolation protocol for the newborn should be selected according to the infection status of the mother. It is not known whether monkeypox virus is present in breast milk, and pasteurized breast milk can be given to newborns when breastfeeding is considered. CONCLUSION: This review presents an overview of monkeypox in the perinatal period and guides the future research direction.

[Short-term persistent symptoms in preschool children with mild/common coronavirus disease 2019 caused by Omicron variant infection after discharge: a follow-up study]. / Omicronå˜å¼‚æ ªæ„ŸæŸ“çš„è½»åž‹/æ™®é€šåž‹æ–°åž‹å† çŠ¶ç— æ¯’è‚ºç‚Žå­¦é¾„å‰å„¿ç«¥å‡ºé™¢åŽçŸ­æœŸç›¸å ³æŒç»­ç—‡çŠ¶çš„éšè®¿.

OBJECTIVES: To investigate the persistent symptoms in preschool children after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant infection, and to provide a basis for developing follow-up plans after infection and reducing and preventing related symptoms after infection. METHODS: The children, aged 0-5 years, who had Omicron BA.2 infection and were discharged from the pediatric ward of Shanghai Renji Hospital South Branch from April 13 to May 8, 2022, were enrolled as subjects, and related demographic and clinical data were collected. The children were followed up from the time to SARS-CoV-2 clearance for two consecutive tests with an interval of >24 hours till 4-5 weeks after clearance, and telephone follow-up was performed on the primary caregivers to investigate related persistent symptoms. RESULTS: Among the 103 children who met the inclusion criteria, there were 61 boys and 42 girls, with a median age of 18 months. The primary caregivers who had received two or more doses of COVID-19 vaccine accounted for 64.1% (66/103). Fever (98.1%, 101/103) was the most common symptom in these children, followed by cough/expectoration (63.1%, 65/103), gastrointestinal problems (37.9%, 39/103), loss of appetite (30.1%, 31/103), weakness (27.2%, 28/103), and nasal obstruction/runny nose (16.5%, 17/103). The follow-up at 1 month after discharge reported that 44 children (42.7%) had at least one persistent symptom, including respiratory symptoms in 14 children (13.6%) and gastrointestinal problems in 19 children (18.4%). The children whose primary caregivers received two or more doses of COVID-19 vaccine had a significantly shorter time to SARS-CoV-2 clearance than those whose primary caregivers did not receive or only received one dose of COVID-19 vaccine (P<0.05), while there was no significant difference between the two groups in the proportion of children with at least one persistent symptom (P>0.05). CONCLUSIONS: Nearly half of the preschool children may have related persistent symptoms after SARS-CoV-2 Omicron variant infection, mainly gastrointestinal and respiratory symptoms. Most of the symptoms may be mild, and continuous follow-up is needed to observe their outcomes. Vaccination of COVID-19 vaccine for primary caregivers has a certain protective effect on children.

Management experience of a designated hospital for children with coronavirus disease 2019. / æ–°åž‹å† çŠ¶ç— æ¯’è‚ºç‚Žå„¿ç«¥å®šç‚¹åŒ»é™¢ç®¡ç†ç»éªŒåˆ†äº«.

The global pandemic of coronavirus disease 2019 (COVID-19) has brought great challenges to the traditional medical model. During the outbreak of COVID-19 in Shanghai, China, from March to May, 2022, there was a significant increase in the number of pediatric cases due to high transmissibility, immune escape, and vaccine breakthrough capacity of Omicron variants. The designated hospitals for children with COVID-19 served as a connecting link between children's specialized hospitals and mobile cabin hospitals. From April 7 to June 2, 2022, a total of 871 children with COVID-19 were admitted to Renji Hospital, Shanghai Jiao Tong University School of Medicine (South Branch), a designated hospital for children with COVID-19. Among these patients, 568 (65.2%) were children under 3 years old, 870 (99.9%) were mild or moderate, and 1 was severe. This article reports the experience in the management of pediatric cases in this designated hospital, which included the following aspects: establishing an optimal case-admission process; strengthening multidisciplinary standardized diagnosis and treatment; optimizing the management, warning, and rescue system for severe COVID-19; implementing family-centered nursing care; formulating an individualized traditional Chinese medicine treatment regimen; optimizing the discharge process and strengthening bed turnover; implementing strict whole-process control to reduce the risk of nosocomial infection; constructing a structured medical record system and using information platforms to adapt to the work mode of large-volume cases; conducting scientific research and sharing the experience in diagnosis and treatment.

Protective Effect of a Water-Soluble Carotenoid-Rich Extract of Cordyceps militaris against Light-Evoked Functional Vision Deterioration in Mice.

Light-evoked retinal photodamage is considered an important factor contributing to functional vision deterioration and can even lead to light maculopathy or dry age-related macular degeneration. Loss of visual acuity (VA) and visual contrast sensitivity function (VCSF) are the major symptoms of retinal degenerative diseases. Cordyceps militaris is a carotenoid-rich Chinese medicinal fungus with antioxidant, anti-inflammatory, and immunomodulatory functions. C. militaris extract is a natural substance, and its bioactive constituents have been shown to confer health benefits, but their application in retinal tissue and functional vision protection in vivo remain incompletely understood. In the present study, we evaluated the influence of water-soluble, carotenoid-rich C. militaris extracts on the visual performance of light-damaged mouse retinas in vivo, using adult female CD-1® (ICR) albino mice. We showed that oral administration of this C. militaris extract (10 mg/kg, twice daily) protected the neural retina tissue against light-evoked photoreceptor cell death, reduced Müller cell hypertrophic gliosis, and elevated GSH levels and promoted the recovery of VA- and VCSF-thresholds, especially for high spatial frequency-characterized vision. These results suggest that, probably because of its water-soluble carotenoids, C. militaris extract has the potential to prevent or treat light-induced visual dysfunction.

Derivation and validation of a prediction model for neonate unplanned rehospitalization in a tertiary center in China.

BACKGROUND: To construct and externally validate a prediction model for neonate unplanned rehospitalization within 31 days of discharge. METHODS: A retrospective study was performed in the Department of Neonatology of the Children's Hospital of Fudan University. A binominal regression method was applied to construct and validate the prediction model. Analysis was performed on a total of 11,116 neonates with an index admission between 11/1/2016 and 12/31/2018. Neonates admitted from 11/1/2016 to 1/31/2018 were used for the selection of prognostic variables and construction of the model. Model validation was then performed with neonates admitted from 2/1/2018 to 12/31/2018. RESULTS: The rehospitalization rate for neonates was 3.27% (373/11,116). A total of 512 neonates were enrolled for the construction of the prediction model. Gestational age (GA), NICU length of stay (LOS), nonmedical order discharge and younger maternal age were strongly correlated with rehospitalization. By incorporating these 4 strong risk factors, we constructed a model to predict neonate unplanned rehospitalization within 31 days of discharge. The formula was turned into a nomogram for use in clinical practice. The nomogram has a total score of 180, with a predicted risk from 0 to 100%. Neonates are at high risk for rehospitalization if they have a total score greater than 39 points, according to the cutoff point established by the Youden index. The model was shown to have good discriminatory ability, with area under the receiver operating characteristic curves of 0.68 and 0.65 in the model construction and validation datasets, respectively. A total of 39 points is the cutoff for follow-up. CONCLUSIONS: The model is able to predict neonate unplanned rehospitalization well. A total score greater than 39 indicates that follow-up is necessary.

[Exploring the Stress, Psychological Distress, and Stress-relief Strategies of Taiwan Nursing Staffs Facing the Global Outbreak of COVID-19].

BACKGROUND: The global outbreak of coronavirus disease (COVID-19) began in December 2019. The high levels of stress experienced by nurses during this pandemic may have immediate and long-term effects on their mental health. PURPOSE: To explore the stress and psychological problems of nurses during this pandemic and to identify strategies used by these nurses to relieve stress. METHODS: A cross-sectional online survey was conducted that included a basic information datasheet, stress of nursing staff during COVID-19 outbreak scale, psychological distress scale, and stress relief methods survey form. Convenience sampling was used and a total of 469 practicing nurses participated in this study. RESULTS: Most of the participants expressed concerns about living problems (72.7%). On the stress questionnaire, the facets of "burden of taking care of patients" and "worries about social isolation" earned the first and second highest scores, respectively. In terms of items, "worrying about infecting family members and friends" and "worrying about being separated from family after being infected" earned the two highest scores (2.35 ± 0.79 and 2.17 ± 0.92, respectively). Scores for psychological distress averaged 5.49 ± 3.83, with stress anxiety (1.32 ± 0.84) earning the highest mean subscale score followed by distress and irritability (1.17 ± 0.92) and depression (1.12 ± 0.94). Nearly two-thirds (61.8%) of the participants earned psychological and emotional distress scores within the 'normal' range, and 3.4% earned scores indicating severe distress. "Receiving education and training" was the most common method used by the participants to relieve stress (2.27 ± 0.51). CONCLUSIONS: The following six strategies are proposed based on the above findings: (1) Caring: provide psychological assessment and care; (2) Supporting: create a friendly team atmosphere and provide support; (3) Inquiring: recruit volunteers with relevant experience; (4) Informing: provide timely, open, and transparent epidemic-prevention information; (5) Equipping: provide complete and appropriate epidemic-prevention education and training; (6) Assisting: establish a strategy for family support and caring to reduce the stress and worries of nurses.

[Post-stroke constipation treated with acupoint embedding therapy: a multi-center randomized controlled trial].

OBJECTIVE: To verify the clinical effect of acupoint embedding therapy on post-stroke constipation. METHODS: The multi-central randomized controlled trial was adopted. 210 patients of post-stroke constipation were divided into an acupoint embedding group (105 cases, 4 cases dropped off) and a sham-embedding group (105 cases, 6 cases dropped off). In the acupoint embedding group, the acupoint embedding therapy was used at Tianshu (ST 25), Daheng (SP 15), Xiawan (CV 10), Zhongwan (CV 12), Qihai (CV 6), Guanyuan (CV 4) and Daju (ST 27). In the sham-embedding group, the sham-embedding therapy was given, in which, the acupoint selection, needle devices and manipulation were the same as the acupoint embedding group. But, no absorbable surgical suture was used in the needle tube. The treatment was given once every two weeks and 4 treatments were required in either group. It was to compare the weekly average complete spontaneous bowel movements (CSBMs) during treatment (from the 3rd to the 8th week) between the two groups, the weekly average spontaneous bowel movements (SBMs), Bristol stool form score (BSFS), the score of the patient assessment of constipation quality of life questionnaire (PAC-QOL) and the score of defecation difficulty before and after treatment. RESULTS: The percentage of the cases with weekly average CSBMs ≥ 3 times in the patients of the acupoint embedding group was higher markedly than the sham-embedding group [91.1% (92/101) vs 43.4% (43/99), P<0.01]. Compared with the values before treatment, the weekly average SBMs and BSFS scores after treatment were all increased obviously in the two groups (P<0.01), and PAC-QOL score and the score of defecation difficulty were reduced remarkably (P<0.01). After treatment, the increase range of SBMs and BSFS scores, as well as the decrease range of PAC-QOL score and the defecation difficulty score in the acupoint embedding group were all higher than the sham-embedding group respectively (P<0.05). CONCLUSION: The acupoint embedding therapy remarkably increases the spontaneous bowel movements, improves in feces form and defecation difficulty and strengthens the quality of life in the patients of post-stroke constipation.

A manganese-salen complex as dipeptidyl peptidase IV inhibitor for the treatment of type 2 diabetes.

A manganese Schiff base complex with N,N'-1,2-phenylenediamine-bis(salicyladimine) was synthesized and characterized by X-ray crystallography. This complex was administered intragastrically to alloxan-diabetic mice 3 weeks. In vivo tests showed that the complex significantly lowered serum glucose levels in alloxan-diabetic mice at doses of 77 mg V kg-1. Meanwhile, this complex was investigated as dipeptidyl peptidase IV (DPP-IV) inhibitor for the treatment of type 2 diabetes. The compound exhibit moderate inhibition against DPP-IV and possessed an IC50 value of 30 µM. Lineweaver-Burk transformation of the inhibition kinetics data demonstrated that it was a noncompetitive inhibitor of DPP-IV and Ki value was 136.3 µM. Moreover, molecular modeling studies suggested that the complex could fit well within the active-site cleft of DPP-IV. An acute toxicity study showed that animals treated intragastically with complex 1 at a dose of 5.0 g/kg did not show any significantly abnormal signs. These preliminary results suggest that the manganese Schiff base complex can induce a hypoglycemic effect in alloxan-diabetic mice.

Determination of Eleven Organophosphorus Pesticide Residues in Textiles by Using HPLC-HRMS.

The overuse of organophosphorus pesticides on cotton production is a big concern in China today. Therefore, developing methods for the rapid screening and confirming of pesticide residues in textiles has become a top public health security priority. Here, a method was established for the rapid screening and quantifying of 11 kinds of organophosphorus pesticides (ethoprophos, coumaphos, profenofos, diazinon, ethion, parathion, phosalone, quinalphos, dicrotophos, azinphos methyl, and tribuphos) in textiles by high-performance liquid chromatography high-resolution mass spectrometry (HPLC-HRMS). Rapid screening and quantifying could be completed by using software of Peakview and MultiQuant. Samples were extracted by the method of modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) and analyzed in the positive mode with MS detection. The results showed that the limits of detection were between 0.1 and 5.0 ng g-1, with correlation coefficients above 0.9990. The recoveries were in the range of 70.3 - 109.8%, with relative standard deviations from 5.1 to 16.4%. This method is accurate and simple, which can be used in the rapid screening and quantitative analysis of 11 kinds of organophosphorus pesticides in textiles.

Synthesis and characterization of oxidovanadium complexes as enzyme inhibitors targeting dipeptidyl peptidase IV.

Two oxidovanadium(IV) complexes carrying Schiff base ligands obtained from the condensation of 4,5-dichlorobenzene-1,2-diamine and salicylaldehyde derivatives were synthesised and characterised, including their X-ray crystallographic structures. They were evaluated as dipeptidyl peptidase IV (DPP-IV) inhibitors for the treatment of type 2 diabetes. These compounds were moderate inhibitors of DPP-IV, with IC50 values of ca. 40µM. In vivo tests showed that complexes 1 and 2 could lower significantly the level of glucose in the blood of alloxan-diabetic mice at doses of 22.5mgV·kg-1 and 29.6mgV·kg-1, respectively. Moreover, molecular modeling studies suggested that the oxidovanadium complexes 1 and 2 could fit well into the active-site cleft of the kinase domain of DPP-IV. To the best of our knowledge, this is the first report of vanadium complexes capable of inhibiting DPP-IV.

Expression and regulation of microRNA-29a and microRNA-29c in early diabetic rat cataract formation.

AIM: To determine the role of microRNA (miRNA)-29a and miRNA-29c in the regulation of apoptosis in early rat diabetic cataract formation. METHODS: Streptozotocin (STZ)-induced diabetic Sprague-Dawley (SD) rats were used in the study. The expression level of miRNA-29a, miRNA-29c, and BCL2-modifying factor (BMF) in lens epithelial cells (LECs) samples were measured using quantitative real-time polymerase chain reaction. Prediction algorithms of miRanda, TargetScan 6.2, and mirRDB to perform a miRNA gene network analysis were used for the potential miRNA-29a and miRNA-29c targets. RESULTS: The miRNA-29a and miRNA-29c expression levels were all significantly lower in the control group compared to the 2 and 4wk diabetic samples (P<0.01). The network analysis indicated that one miRNA-29a and miRNA-29c targets was BMF. There was significantly higher expression of BMF mRNA compared to the normal controls (P<0.01). CONCLUSION: Apoptosis occurs in rat LECs following high blood glucose exposure. It is likely that apoptosis during diabetic cataract formation involves the decreased expression of miRNA-29a and miRNA-29c and the increased expression of BMF.

Maternal circulating concentrations of tumor necrosis factor-alpha, leptin, and adiponectin in gestational diabetes mellitus: a systematic review and meta-analysis.

Gestational diabetes mellitus (GDM) is one of the most common pregnancy complications. Inflammation may play a role in the pathogenesis of GDM. We performed a systematic review and meta-analysis to determine whether maternal serum concentration of tumor necrosis factor-alpha (TNF-α), leptin, and adiponectin were associated with GDM. A systematic search of PubMed and Medline was undertaken. In total, 27 trials were evaluated by meta-analyses using the software Review Manager 5.0. The results showed that maternal TNF-α (P = 0.0003) and leptin (P < 0.00001) concentrations were significantly higher in GDM patients versus controls. However, maternal adiponectin (P < 0.00001) concentration was significantly lower in GDM patients compared with controls. Subgroup analysis taking in consideration the effect of obesity on maternal adipokine levels showed that circulating levels of TNF-α and leptin remained elevated in GDM patients compared to their body mass index (BMI) matched controls, and adiponectin level remained depressed in GDM individuals. Our findings strengthen the clinical evidence that GDM is accompanied by exaggerated inflammatory responses.

An investigation on the catalytic capacity of dolomite in transesterification and the calculation of kinetic parameters.

The catalytic capacity of dolomite in transesterification was investigated and the kinetic parameters were calculated. The activated dolomites as transesterification catalyst were characterized by X-ray diffraction, nitrogen adsorption and desorption and Hammett indicator method, where the original dolomite was analyzed by thermogravimetric and X-ray fluorescence in advance. Its potential catalytic capacity was validated from aspects of the activated temperature and the reused property, where the reliability of the experimental system was also examined. Then, influences of the catalyst added amount, the mole ratio of methanol to oil, the transesterification temperature and the transesterification time on the catalytic capacity were investigated. Finally, kinetic parameters of the transesterification catalyzed by the activated dolomite were calculated.

Delineating chromosomal breakpoints in radiation-induced papillary thyroid cancer.

Recurrent translocations are well known hallmarks of many human solid tumors and hematological disorders, where patient- and breakpoint-specific information may facilitate prognostication and individualized therapy. In thyroid carcinomas, the proto-oncogenes RET and NTRK1 are often found to be activated through chromosomal rearrangements. However, many sporadic tumors and papillary thyroid carcinomas (PTCs) arising in patients with a history of exposure to elevated levels of ionizing irradiation do not carry these known abnormalities. We developed a rapid scheme to screen tumor cell metaphase spreads and identify candidate genes of tumorigenesis and neoplastic progression for subsequent functional studies. Using a series of overnight fluorescence in situ hybridization (FISH) experiments with pools comprised of bacterial artificial chromosome (BAC) clones, it now becomes possible to rapidly refine breakpoint maps and, within one week, progress from the low resolution Spectral Karyotyping (SKY) maps or Giemsa-banding (G-banding) karyotypes to fully integrated, high resolution physical maps including a list of candiate genes in the critical regions.

Comparison between two different methods of immobilizing NGF in poly(DL-lactic acid-co-glycolic acid) conduit for peripheral nerve regeneration by EDC/NHS/MES and genipin.

For surface modification and nerve regeneration, chitosan, followed by nerve growth factor (NGF), was immobilized onto the interior surface of poly (lactic acit-co-glycolic) conduits, using EDC/NHS/MES system (EDCs) and genipin (GP). Four new conduits were, therefore, obtained and named by immobilizing order-EDCs/EDCs, GP/EDCs, EDCs/GP, and GP/GP groups. The immobilized methods used were evaluated and compared, respectively. The researchers found that the EDCs- and GP-cross-linked chitosan displayed higher hydrophilic than pure poly (DL-lactic acid-co-glycolic acid) (PLGA) in water contact angle experiment, which meant the cell compatibility was improved by the modification. Scanning electron microscopic observations revealed that the GP-cross-linking of chitosan greatly improved cell compatibility while cultured rat PC12 cells were flatter and more spindle-shaped than EDCs-cross-linked chitosan. The results concerning the GP-cross-linked chitosan revealed significant proliferation of the seeded cells relative to pure PLGA films, as determined by counting cells and MTT assay. The NGF was released from the modified conduits in two separate periods--an initial burst in 5 days and then slow release from day 10 to day 40. The GP/EDCs group had the highest NGF value among all groups after the 5th day. Finally, the controlled-release conduits were used to bridge a 10 mm rat sciatic nerve defect. Six weeks following implantation, morphological analysis revealed the highest numbers of myelinated axons in the midconduit and distal regenerated nerve in GP/EDCs group. Therefore, the results confirm that GP/EDCs groups with good cell compatibility and effective release of NGF can considerably improve peripheral nerve regeneration.

BAC-FISH assays delineate complex chromosomal rearrangements in a case of post-Chernobyl childhood thyroid cancer.

Structural chromosome aberrations are known hallmarks of many solid tumors. In the papillary form of thyroid cancer (PTC), for example, activation of the receptor tyrosine kinase (RTK) genes, RET and neurotrophic tyrosine kinase receptor type I (NTRK1) by intra- and interchromosomal rearrangements has been suggested as a cause of the disease. However, many phenotypically similar tumors do not carry an activated RET or NTRK-1 gene or express abnormal ret or NTRK-1 transcripts. Thus, we hypothesize that other cellular RTK-type genes are aberrantly expressed in these tumors. Using fluorescence in situ hybridization-based methods, we are studying karyotype changes in a relatively rare subgroup of PTCs, i.e., tumors that arose in children following the 1986 nuclear accident in Chernobyl, Ukraine. Here, we report our technical developments and progress in deciphering complex chromosome aberrations in case S48TK, an aggressively growing PTC cell line, which shows an unusual high number of unbalanced translocations.

DNA probe pooling for rapid delineation of chromosomal breakpoints.

Structural chromosome aberrations are hallmarks of many human genetic diseases. The precise mapping of translocation breakpoints in tumors is important for identification of genes with altered levels of expression, prediction of tumor progression, therapy response, or length of disease-free survival, as well as the preparation of probes for detection of tumor cells in peripheral blood. Similarly, in vitro fertilization (IVF) and preimplantation genetic diagnosis (PGD) for carriers of balanced, reciprocal translocations benefit from accurate breakpoint maps in the preparation of patient-specific DNA probes followed by a selection of normal or balanced oocytes or embryos. We expedited the process of breakpoint mapping and preparation of case-specific probes by utilizing physically mapped bacterial artificial chromosome clones. Historically, breakpoint mapping is based on the definition of the smallest interval between proximal and distal probes. Thus, many of the DNA probes prepared for multiclone and multicolor mapping experiments do not generate additional information. Our pooling protocol, described here with examples from thyroid cancer research and PGD, accelerates the delineation of translocation breakpoints without sacrificing resolution. The turnaround time from clone selection to mapping results using tumor or IVF patient samples can be as short as 3 to 4 days.

Rapid mapping of chromosomal breakpoints: from blood to BAC in 20 days.

Structural chromosome aberrations and associated segmental or chromosomal aneusomies are major causes of reproductive failure in humans. Despite the fact that carriers of reciprocal balanced translocation often have no other clinical symptoms or disease, impaired chromosome homologue pairing in meiosis and karyokinesis errors lead to over-representation of translocations carriers in the infertile population and in recurrent pregnancy loss patients. At present, clinicians have no means to select healthy germ cells or balanced zygotes in vivo, but in vitro fertilization (IVF) followed by preimplantation genetic diagnosis (PGD) offers translocation carriers a chance to select balanced or normal embryos for transfer. Although a combination of telomeric and centromeric probes can differentiate embryos that are unbalanced from normal or unbalanced ones, a seemingly random position of breakpoints in these IVF-patients poses a serious obstacle to differentiating between normal and balanced embryos, which for most translocation couples, is desirable. Using a carrier with reciprocal translocation t(4;13) as an example, we describe our state-of-the-art approach to the preparation of patient-specific DNA probes that span or 'extent' the breakpoints. With the techniques and resources described here, most breakpoints can be accurately mapped in a matter of days using carrier lymphocytes, and a few extra days are allowed for PGD-probe optimization. The optimized probes will then be suitable for interphase cell analysis, a prerequisite for PGD since blastomeres are biopsied from normally growing day 3--embryos regardless of their position in the mitotic cell cycle. Furthermore, routine application of these rapid methods should make PGD even more affordable for translocation carriers enrolled in IVF programs.