23 research outputs found
DNA methods for identification of Chinese medicinal materials
As adulterated and substituted Chinese medicinal materials are common in the market, therapeutic effectiveness of such materials cannot be guaranteed. Identification at species-, strain- and locality-levels, therefore, is required for quality assurance/control of Chinese medicine. This review provides an informative introduction to DNA methods for authentication of Chinese medicinal materials. Technical features and examples of the methods based on sequencing, hybridization and polymerase chain reaction (PCR) are described and their suitability for different identification objectives is discussed
A Lethal Sequelae of Spinal Infection Complicating Surgery and Radiotherapy for Head and Neck Cancer
Patients who have undergone neck dissection and radiotherapy are at risk of cervical spine infections. Furthermore, previous radiotherapy and cervical spine infections can lead to fistula formation to the subarachnoid space and intracranial infection. This report discusses the serious consequences of a missed cervical spine infection including cerebrospinal fluid fistula formation and persistent central nervous system infection, and serves as a reminder to clinicians of the possible association between cervical spine infections and prior head and neck surgery and radiotherapy. In all such cases, the posterior pharyngeal wall should be inspected during follow-up. Despite the appearance of an intracranial infection, the cervical spine should be investigated, especially if the response to appropriate antibiotics is suboptimal
SEIPIN Regulates Lipid Droplet Expansion and Adipocyte Development by Modulating the Activity of Glycerol-3-phosphate Acyltransferase
Berardinelli-Seip congenital lipodystrophy 2 (BSCL2) is caused by loss-of-function mutations in SEIPIN, a protein implicated in both adipogenesis and lipid droplet expansion but whose molecular function remains obscure. Here, we identify physical and functional interactions between SEIPIN and microsomal isoforms of glycerol-3-phosphate acyltransferase (GPAT) in multiple organisms. Compared to controls, GPAT activity was elevated in SEIPIN-deficient cells and tissues and GPAT kinetic values were altered. Increased GPAT activity appears to underpin the block in adipogenesis and abnormal lipid droplet morphology associated with SEIPIN loss. Overexpression of Gpat3 blocked adipogenesis, and Gpat3 knockdown in SEIPIN-deficient preadipocytes partially restored differentiation. GPAT overexpression in yeast, preadipocytes, and fly salivary glands also formed supersized lipid droplets. Finally, pharmacological inhibition of GPAT in Seipin-/- mouse preadipocytes partially restored adipogenesis. These data identify SEIPIN as an evolutionarily conserved regulator of microsomal GPAT and suggest that GPAT inhibitors might be useful for the treatment of human BSCL2 patients
Lack of Evidence for Human-to-Human Transmission of Avian Influenza A (H9N2) Viruses in Hong Kong, China 19991
In April 1999, isolation of avian influenza A (H9N2) viruses from humans was confirmed for the first time. H9N2 viruses were isolated from nasopharyngeal aspirate specimens collected from two children who were hospitalized with uncomplicated, febrile, upper respiratory tract illnesses in Hong Kong during March 1999. Novel influenza viruses have the potential to initiate global pandemics if they are sufficiently transmissible among humans. We conducted four retrospective cohort studies of persons exposed to these two H9N2 patients to assess whether human-to-human transmission of avian H9N2 viruses had occurred. No serologic evidence of H9N2 infection was found in family members or health-care workers who had close contact with the H9N2-infected children, suggesting that these H9N2 viruses were not easily transmitted from person to person
Transflective Single Cell Gap TN LCD Using a Patterned Polarizer and a Twisted LC Retarder
The role of AGPAT2 in lipid droplet biogenesis and insulin signalling
1-Acylglycerol-3-Phosphate O-Acyltransferase 2 (AGPAT2) is an intermediate enzyme esterifying the sn-2 position of lysophosphatidic acid (LPA) to make phosphatidic acid (PA) in the de novo synthesis of glycerophospholipids (GPLs) and triacylglycerol (TAG). It has been reported that the absence of AGPAT2 elevated PA levels resulting in the increase of ER surface tension, thus altering the growth of LDs. However, the molecular link in between AGPAT2 and lipid droplet biogenesis remains obscure in the cells. Here, I showed that AGPAT2 controlled lipid droplet (LD) growth and maturation. AGPAT2 deficiency resulted in the formation of supersized lipid droplets and the accumulation of numerous nascent LDs. Furthermore, the depletion of glycerol-3-phostphate 3/4 (GPAT3/4), or the over-expression of CDP-diacylglycerol synthases (CDS1/2) and Seipin decreased the size of LDs in AGPAT2-deficient cells.This thesis also identified a novel regulatory mechanism to explain the elevated PA levels in AGPAT2-deficient cells. It was interesting to observe that the fluorescence intensity of CDS1/2 in AGPAT2-deficient cells was reduced significantly. Furthermore, CDS2, but not CDS1, was found to be the binding partner of AGPAT2 among all AGPAT family members. Most importantly, CDS2 protein level and CDS activity were decreased significantly in AGPAT2-deficient cells and tissues. In all, our results unveil a novel mechanism by which AGPAT2 deficiency facilitates CDS2 degradation and thus leads to an increase of cellular PA. Finally, this thesis also reported that the change of PA and all down-stream lipid intermediates by over-expressing of GPAT3 and AGPAT10 decreased AKT phosphorylation, causing insulin resistance. This thesis may contribute a mechanistic link between the effect of altered AGPATs levels and CGL1 or diabetes
Primary colorectal lymphoma: Case series and literature review
Primary colorectal lymphoma is a rare disease that accounts for 0.16% of colorectal malignancies. Treatments include surgical intervention with or without chemotherapy. Outcome of this intervention among the Chinese population are lacking. Perforation resulting from chemotherapy may need further exploration. A retrospective review of patient records was performed among those who were diagnosed with colorectal malignancy in a single center from January 1998 to June 2009. Ten patients met Dawsons diagnostic criteria for primary colorectal lymphoma [0.66% (10/1516) of all colorectal malignancies]. The male-to-female ratio was 9:1, and median age at diagnosis was 76 years. The most common site was the cecum (n = 5). B-cell lymphoma was present in eight patients. Seven patients underwent surgical intervention. The median follow-up of all patients was 16.5 months. Median survival was 17 months and 13 months in the surgical and chemotherapy group, respectively. Primary colonic lymphoma is a rare disease. Surgical intervention appeared to be superior to chemotherapy alone, but the findings were limited by the small number of patients in this study. Whether surgery or chemotherapy should be offered first remains unknown and requires further research
Primary colorectal lymphoma: Case series and literature review
Primary colorectal lymphoma is a rare disease that accounts for 0.16% of colorectal malignancies. Treatments include surgical intervention with or without chemotherapy. Outcome of this intervention among the Chinese population are lacking. Perforation resulting from chemotherapy may need further exploration. A retrospective review of patient records was performed among those who were diagnosed with colorectal malignancy in a single center from January 1998 to June 2009. Ten patients met Dawson's diagnostic criteria for primary colorectal lymphoma [0.66% (10/1516) of all colorectal malignancies]. The male-to-female ratio was 9:1, and median age at diagnosis was 76 years. The most common site was the cecum (n = 5). B-cell lymphoma was present in eight patients. Seven patients underwent surgical intervention. The median follow-up of all patients was 16.5 months. Median survival was 17 months and 13 months in the surgical and chemotherapy group, respectively. Primary colonic lymphoma is a rare disease. Surgical intervention appeared to be superior to chemotherapy alone, but the findings were limited by the small number of patients in this study. Whether surgery or chemotherapy should be offered first remains unknown and requires further research
SEIPIN regulates lipid droplet expansion and adipocyte development by modulating the activity of glycerol-3-phosphate acyltransferase
Summary Berardinelli-Seip congenital lipodystrophy 2 (BSCL2) is caused by loss-of-function mutations in SEIPIN, a protein implicated in both adipogenesis and lipid droplet expansion but whose molecular function remains obscure. Here, we identify physical and functional interactions between SEIPIN and microsomal isoforms of glycerol-3-phosphate acyltransferase (GPAT) in multiple organisms. Compared to controls, GPAT activity was elevated in SEIPIN-deficient cells and tissues and GPAT kinetic values were altered. Increased GPAT activity appears to underpin the block in adipogenesis and abnormal lipid droplet morphology associated with SEIPIN loss. Overexpression of Gpat3 blocked adipogenesis, and Gpat3 knockdown in SEIPIN-deficient preadipocytes partially restored differentiation. GPAT overexpression in yeast, preadipocytes, and fly salivary glands also formed supersized lipid droplets. Finally, pharmacological inhibition of GPAT in Seipin−/− mouse preadipocytes partially restored adipogenesis. These data identify SEIPIN as an evolutionarily conserved regulator of microsomal GPAT and suggest that GPAT inhibitors might be useful for the treatment of human BSCL2 patients