BACKGROUND:Very smal embryonic-like stem cells are a kind of non-hemopoietic stem cells, which have similar biological characteristics to embryonic stem cells. But the method of its culture and in vitro proliferation is rarely reported. Studies have speculated that human embryonic fibroblasts can provide a good microenvironment for in vitro culture and proliferation of very smal embryonic-like stem cells.
OBJECTIVE:To isolate and cultivate human embryonic fibroblasts derived from human embryonic trunks and to establish a feeder layer culture system of human embryonic fibroblasts for culturing very smal embryonic-like stem cells derived from human bone marrow.
METHODS:The human embryonic fibroblasts were isolated from the subcutaneous connective tissue of human embryos at pregnant 5-9 weeks using trypsin digestion method. Different concentrations of mitomycin C were used to pretreat feeder layers, which were used for cultivating very smal embryonic-like stem cells derived from human bone marrow. The effects of human embryonic fibroblasts and feeder layers were assessed by cel morphology and growth curves.
RESULTS AND CONCLUSION:The human embryonic fibroblasts were successful y isolated and cultivated from human embryos, and they could be passaged beyond the 24th generation. The biologic characteristics of the cells had no changes after passage and cryopreservation. The optimal concentration of mytomcin C to inhibit proliferation of human embryonic fibroblasts was l2 mg/L for 3 hours. The human embryonic fibroblasts derived from human embryos are successful y isolated and cultivated and to produce feeder layers for very smal embryonic-like stem cells derived from human bone marrow.

With citric acid as carbon source and different amino acids as nitrogen source,the nitrogen-doped carbon was synthesized by one-step hydrothermal method under the condition of no catalyst.The pre-experiments show that arginine-doped carbon dots(CDs-Arg) with relatively high fluorescence quantum yield (33.25％) were picked out for further study.Furthermore,we studied the physical and chemical properties of CDs-Arg through a series of spectral,electric potential,particle size,X ray and elemental analysis experiments.At the same time,the stabilities of the nanoparticles towards different pH,temperatures,excitation lasers or redox conditions were studied.And the MTr and in vivo distribution experiments were also conducted for the toxicity and metabolism studies.The experimental results showed that the arginine doped carbon dots has high fluorescence efficiency,good stability,and extremely low toxicity.And the water-soluble small particles of CDs-Arg nanoparticles showed that the nanoparticles can be excreted through the glomerulus.These results show that the CDs-Arg Nanoparticles are biocompatible nanoparticles and have potential applications in biological imaging and can serve as a monitor of drug metabolism.

Nerve-specific fluorescent agents can be used as nerve markers in animals to guide surgical procedures and reduce the incidence of intraoperative nerve injury.In this study, the structure of oxazine mother nucleus was modified.A series of oxazine derivative fluorescent dyes YQN-3-YQN-6 were obtained by mass spectrometry and 1H NMR, which can highlight the peripheral nerve structure of rats.Among a series of targeted fluorescent dyes, YQN-3 had emission peaks near NIR and showed highly specific nerve targeting signals in the brachial plexus and sciatic nerves 4 h after intravenous administration.In addition, YQN-3 can accurately locate and identify recurrent laryngeal nerves during thyroidectomy, thus preserving the integrity of these nerves during surgery.With its simple synthesis and low toxicity, YQW-3 can be potentially applied for clinical neural tissue imaging.

To develop a long-term released and implantable biodegradable fiber carrier for hydrophobic drug incorporation, fibers were fabricated by organic phase separation method. The structure of the fiber was observed by scanning electron microscopy and the state of the drug dispersed in the polymer was measured by differential scanning colorimetry (DSC) and Fouvier transform infrared spectroscopy (FTIR). The drug loading content and release profiles were determined by high performance liquid chromatography (HPLC) and ultra-violet spectrophotometry, respectively. Blank and drug loaded fibers were successfully fabricated and the drug was entirely encapsulated into the fiber. The drug was dispersed in the polymer with minicrystal and noncrystal form. The drug release profile was long-term sustained and could be regulated. The PLLA fibers in micrometer range successfully fabricated by organic phase separation method could be taken as sustained release and implantable drug carrier.
Absorbable Implants ; Delayed-Action Preparations ; Drug Carriers ; chemical synthesis ; chemistry ; Drug Implants ; administration & dosage ; chemical synthesis ; Lactic Acid ; administration & dosage ; chemistry ; Nimodipine ; administration & dosage ; Polyesters ; Polymers ; administration & dosage ; chemistry

BACKGROUNDTo determine the value of preoperative cardiopulmonary risk index (CPRI) in predicting the short-term prognosis after lung resection in patients with lung cancer.

METHODSPreoperative clinical data were used to generate a cardiac risk index (CRI) and a pulmonary risk index (PRI). And the value of cardiopulmonary risk index (CPRI) consisting of CRI and PRI in predicting postoperative prognosis was estimated in patients who underwent lung resection at Shanghai Chest Hospital in 1999.

RESULTSA total of 625 consecutive patients were studied. Postoperative complications occurred in 49 patients (7.8%), including 8 deaths within 30 days of operation. In the total group, CRI, PRI and CPRI scores ranged from 1 to 3, 0 to 5 and 1 to 7, respectively. There were 489 patients with CPRI < 4, and 136 with CPRI≥4. Using CPRI≥4 as a threshold for predicting postoperative complications, the sensitivity, specificity and accuracy rate were 75.5%, 82.8% and 82.2% respectively.

CONCLUSIONSThe preoperative CPRI is one of the important indexes in predicting the short-term postoperative prognosis for patients with lung cancer. However, it can not completely predict all of postoperative risks, and should be used together with other factors.

Intraoperative analysis of the position of microelectrode in the globus pallidus only depends on experiences and subjective interpretation of microeletrode recording discharge of neurons during pallidotomy for Parkinson's disease. In this paper is reported a method for objective localization of microeletrode during neurosurgery. This method uses the factor of interspike interval based on microelectrode recordings. It is effective for identifying the change of the globus pallidal organism along the microelectrode pathway and the departure or deviation of the needle-pathway. The classification is consistent with the anatomic structures and the results of neurosurgery. This method can be used as a guide in pallidotomy. Globus pallidus.
Adult ; Aged ; Female ; Globus Pallidus ; surgery ; Humans ; Male ; Microelectrodes ; Middle Aged ; Pallidotomy ; methods ; Parkinson Disease ; surgery ; Stereotaxic Techniques ; Surgery, Computer-Assisted ; methods

Recent progress in targeted metabolic therapy of cancer has been limited by the considerable toxicity associated with such drugs. To address this challenge, we developed a smart theranostic prodrug system that combines a fluorophore and an anticancer drug, specifically 6-diazo-5-oxo-l-norleucine (DON), using a thioketal linkage (TK). This system enables imaging, chemotherapy, photodynamic therapy, and on-demand drug release upon radiation exposure. The optimized prodrug, DON-TK-BM3, incorporating cyanine dyes as the fluorophore, displayed potent reactive oxygen species release and efficient tumor cell killing. Unlike the parent drug DON, DON-TK-BM3 exhibited no toxicity toward normal cells. Moreover, DON-TK-BM3 demonstrated high tumor accumulation and reduced side effects, including gastrointestinal toxicity, in mice. This study provides a practical strategy for designing prodrugs of metabolic inhibitors with significant toxicity stemming from their lack of tissue selectivity.