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Lin Liu

Publications and source records attributed to Lin Liu.

42 records · Page 3Linked to original sources
PubMed2002

Apoptosis recruits two-pore domain potassium channels used for homeostatic volume regulation.

Cell shrinkage is an incipient hallmark of apoptosis and is accompanied by potassium release that decreases the concentration of intracellular potassium and regulates apoptotic progression. The plasma membrane K+ channel recruited during apoptosis has not been characterized despite its importance as a potential therapeutic target. Here we provide evidence that two-pore domain K+ (K(2P)) channels underlie K+ efflux during apoptotic volume decreases (AVD) in mouse embryos. These K(2P) channels are inhibited by quinine but are not blocked by an array of pharmacological agents that antagonize other K+ channels. The K(2P) channels are uniquely suited to participate in the early phases of apoptosis because they are not modulated by common intracellular messengers such as calcium, ATP, and arachidonic acid, transmembrane voltage, or the cytoskeleton. A K+ channel with similar biophysical properties coordinates regulatory volume decreases (RVD) triggered by changing osmotic conditions. We propose that K(2P) channels are the pathway by which K+ effluxes during AVD and RVD and that apoptosis co-opts mechanisms more routinely employed for homeostatic cell volume regulation.

Animals↗
PubMed2002

[Immunodeficiency tuberculosis: report on 5 autopsy cases].

OBJECTIVE: To improve the awareness of immunodeficiency tuberculosis. METHODS: 5 autopsy cases of immunodeficiency tuberculosis from 1972 to 2000 in two hospitals were reviewed. RESULTS: The 5 cases were found to have hypoplasia of or damage in the thymus, among them 3 had massive tuberculous lymphadenitis lesions. Multiorgan lesions were found more in both lungs than in other organs, accompanied by lymphatic spread and blood dissemination. The microscopic feature was atypical tuberculosis with great amounts of Mycobacterium tuberculosis. CONCLUSIONS: Hypoplasia of or damage in the thymus and peripheral lymphoid tissue caused deficiency in the immune response, which resulted in the death of the patients with generalised tuberculosis by blood dissemination and lymphatic spread. The underlying mechanism of immunodeficiency tuberculosis is largely unknown, and further research is needed.

Adolescent↗
PubMed2002

Sentinel lymph nodes lymphoscintigraphy and biopsy in breast cancer.

OBJECTIVES: To determine the clinical value of sentinel lymph node (SLN) detection by lympho- scintigraphy and gamma ray detecting probe (GDP) and to assess the value of hematoxylin and eosin (H&E) staining combined with immunohistochemistry (IHC) analys is for detecting micrometastasis in lymph nodes (LNs). METHODS: Forty-two patients with breast cancer were included in this study. (99)Tc(m)-dextran was injected peritumourally. Lymphoscintigraphy images were obtained in anterior and lateral views. SLNs were removed with the aid of GDP during surgery. A standard axillary lymph nodes (ALNs) dissection was performed. All lymph nodes were first analyzed by HE staining. When all of the SLNs in a patient were negative, the ALNs were subjected to additional HE staining combined with IHC analysis. RESULTS: SLNs were successfully detected and removed in 39 (92.9%) of the 42 patients. The sensitivity, specificity and accuracy of SLN biopsy were 92.9% (13 in 14), 100% (25 in 25) and 97.4% (38 in 39) respectively. Additional HE staining combined with IHC analysis of the ALNs detected micrometastasis in 3 SLNs (2 cases), but there were no positives in the non-sentinal lymph nodes (NSLNs). CONCLUSIONS: This study suggests that lymphoscintigraphy and GDP may be used to detect SLN. Additional HE staining combined with IHC analysis of the ALNs may help predict micrometastasis. Biopsy of SLN may be an accurate method for staging breast cancer.

Adult↗
PubMed2002

Building a genome database using an object-oriented approach.

GOBASE is a relational database that integrates data associated with mitochondria and chloroplasts. The most important data in GOBASE, i. e., molecular sequences and taxonomic information, are obtained from the public sequence data repository at the National Center for Biotechnology Information (NCBI), and are validated by our experts. Maintaining a curated genomic database comes with a towering labor cost, due to the shear volume of available genomic sequences and the plethora of annotation errors and omissions in records retrieved from public repositories. Here we describe our approach to increase automation of the database population process, thereby reducing manual intervention. As a first step, we used Unified Modeling Language (UML) to construct a list of potential errors. Each case was evaluated independently, and an expert solution was devised, and represented as a diagram. Subsequently, the UML diagrams were used as templates for writing object-oriented automation programs in the Java programming language.

Databases, Genetic↗
PubMedDate not supplied

Imaging meiotic spindles by polarization light microscopy: principles and applications to IVF.

Meiotic spindles tether the chromosomes of oocytes and have been found to be structurally abnormal in older women. Conventional methods to image the meiotic spindle, such as immunostaining or transmission electron microscopy, require prior fixation, so they cannot be used clinically, and their utility in developmental studies is limited. Spindles can also be imaged non-invasively based on their birefringence, an inherent optical property of highly ordered molecules, such as microtubules, as they are illuminated with polarized light. Polarized light microscopy has been gainfully applied to embryology for decades, but recently a digital, orientation-independent polarized light microscope, the polscope, has demonstrated the exquisite sensitivity needed to image the low levels of birefringence exhibited by mammalian spindles. Its use of nearly circularly polarized light also produces orientation-independent measures of spindle birefringence, thus providing a method to quantify spindle architecture in living oocytes. The safety and utility of polscope imaging has been demonstrated in mammalian oocytes, including those from women undergoing ICSI. Spindle imaging with the polscope provides structural information closely related to the more invasive immunostaining method, and also enables study of the dynamic architecture of spindles. Profound effects of cooling on meiotic spindles have also been shown, and polscope imaging has been used to optimize thermodynamic stability of oocytes during ICSI. It has been shown that embryos derived from oocytes with normal, intact meiotic spindles exhibit superior development after fertilization and in-vitro culture. The mechanisms underlying age-related disruption of meiotic spindles in women remain unclear, but may relate to factors residing within the chromosomes themselves, since mice engineered to shorten their telomeres exhibit structurally abnormal spindles in their oocytes, and their embryos undergo cell cycle arrest and apoptosis, a phenotype remarkably similar to that observed in oocytes and embryos from older women. A time-lapse video of a mouse oocyte imaged by polscope may be purchased for viewing on the internet at www.rbmonline.com/Article/824 (free to web subscribers).

Aging↗