Ketamine improved depressive-like behaviors via hippocampal glucocorticoid receptor in chronic stress induced- susceptible mice.

Chronic stress is an important factor for depression. Most individuals recover from stress, while some develop into depression. The pathogenesis of resilience or susceptibility remains unclear. Stress activates the hypothalamic-pituitary-adrenal (HPA) axis and releases stress hormones to regulate individual response to stress. Hence, we assessed the effects of chronic social defeat stress (CSDS) on susceptible behaviors, plasma corticosterone (CORT) concentration, glucocorticoid receptor (GR) expressions in hippocampus and medial prefrontal cortex (mPFC). Mice that plasma CORT concentration is increased 2 h after single social defeat stress developed into susceptible mice after 10 d social defeat stress. The plasma CORT concentration was still higher than that of resilient mice 48 h after the last defeat stress. Mice administered CORT via drinking water showed susceptibility. Mifepristone, a GR antagonist improved susceptibility to chronic stress. Single dose ketamine treatment improved depressive-like behaviors, decreased plasma CORT concentration, rescued GR expression and nuclear translocation in the hippocampus of susceptible mice. These results suggested that abnormal CORT concentration after stress may predict susceptibility to depression in clinic. Ketamine may exert the antidepressant effect via normalizing HPA axis response and have significance in the clinic.

Relationship between PI3K-AKT gene expression levels and clinical symptoms in schizophrenia patients / 中华行为医学与脑科学杂志

Objective To detect the mRNA expression levels of PI3KCB and AKT1 genes in the peripheral blood lymphocytes of acute and chronic schizophrenia patients in different stages,and to explore the relationship between them and the clinic symptoms.Methods Twenty-four cases of schizophrenia patients without medication for at least 1 month,19 chronic schizophrenia patients with long-term clozapine medication,and 20 normal controls were involved in the study.The mRNA expression of PI3KCB and AKT1 genes of all the subjects were measured by real-time qRT-PCR,and the positive and negative symptom scales (PANSS) of schizophrenia patients were also evaluated.Spearman's correlation was used to analyze the relationship between PI3KCB,AKT1 and PANSS score.Results The gene expression of PI3KCB in acute schizophrenia patients,chronic schizophrenia patients with clozapine medication and normal control were (0.79±0.04),(0.83±0.08) and (0.87±0.09) respectively,and the difference was significant among the three groups (F=8.77,P=0.001).The AKT1 gene expression levels were (0.80±0.03),(0.27±0.13)and (0.29±0.12) respectively,and the difference was also significant among the three groups (F=302.31,P＜0.01).The PI3KCB mRNA levels of acute schizophrenia patients were significantly lower than the levels in healthy controls (MD =0.09,P=0.002),and the AKT1 mRNA levels of acute schizophrenia patients were significantly higher than the levels in chronic schizophrenia patients (MD=0.53,P＜0.01) and healthy controls (MD =0.51,P＜ 0.01).In schizophrenia patients,no significant relationship was found between PI3KCB,AKT1 expression levels and PANSS scores.Conclusion The gene expression status of PI3K-AKT pathway is significantly different in different stages of acute and chronic schizophrenia and that is no significant relationship with clinic symptoms,and clozapine treatment may affect its gene expression levels.

Effect of dexmedetomidine on apoptosis and CHOP in hypoxia/reoxygenation injury A549 cell / 中国应用生理学杂志

OBJECTIVES@#To investigate the effects of dexmedetomidine (Dex) on injury of A549 cells induced by hypoxia/reoxygenation(H/R)and the influence of C/EBP homologous protein (CHOP) expression.@*METHODS@#Logarithmic growth phase A549 cells(it originated from alveolar type Ⅱ epithelial cell line) were randomly divided into 4 groups (=10):normoxic control group (N), Dex group (D), hypoxia/reoxygenation group (H), hypoxia/reoxygenation + Dex group(HD). At the beginning of modeling, 1 nmol/L Dex was puted into D and HD groups. N and D groups were cultured in the normoxic incubator for 30 h. H and HD group were incubated in the anoxic cultivation for 6 h, fo llowed by normoxic culture for 24 h. Then A549 cells were observed under the inverted microscope to observe the morphological changes. Cell activity was detected by cell counting Kit-8(CCK-8) and the apoptosis index(AI) was detected by in situ end labeling (TUNEL) method. The expression of CHOP、glucose-regulated protein of molecular weight 78 kDa (Grp78)、cysteinyl aspirate-specificprotease-3 (caspase-3) protein and CHOP、Grp78 mRNA were detected by Western blot and RT-PCR.@*RESULTS@#Compared with N group, the number of adherent cells in H group decreased significantly, and cell morphology changed. The absorbance value in H group decreased obviously (<0. 01). The AI value and expression of CHOP, Grp78, caspase-3 proteins and CHOP, Grp78 mRNA were significantly increased (<0.01). Compared with H group, the cell damage in HD group was decreased, the absorbance value increased (<0.01), the number of apoptosis cells decreased relatively (<0.01), the expression of CHOP, caspase-3 protein and CHOP mRNA decreased (<0. 01).@*CONCLUSIONS@#Dex has notable effects against H/R injury, which may be related to effective inhibition of apoptosis mediated by the CHOP's signal path.

An investigation on the situation of bus driver's personality characteristics and its relationship with driving experience / 预防医学

Objective To investigate the relationship between bus drivers' personality characteristics with driving experience and to provide reference for safe driving. Methods A total of 158 bus drivers who work for one year and above were extracted by random sampling from a bus company in Ningbo during March 2016 to May 2016. The survey was carried out by 16 personality factor questionnaire (16PF), and compared with the national norm. Results The subjects were male, and average age was 39.24±6.78. The average bus driving year was 15.54±6.66 and mainly with high school education (62.66%) . The scores of agreeableness (9.21±3.18), intelligence (8.12±1.81), excitability (9.60± 3.26), excitement (10.84±4.59), suspicion (8.94±2.87), introversion (9.01±2.60), experiment (10.18±2.52) and independence (10.51±3.13) of the subjects were significantly lower than the national norm (P<0.05) . The scores of sensitivity (10.67±2.72), anxiety (9.60±3.78) and the self-discipline (13.30±2.42) were significantly higher than the national norm (P<0.05) . And 54.43% of bus drivers have high score in eight sub-personality analysis of mental health factors and 67.09% of them have low score in professional achievement factor. The analysis of personality characteristics of bus drivers with different bus driving experiences showed that the highest stability score was in 16 bus driving years and above, and the highest anxiety score was in 6~ <11 bus driving years and the highest tension and anxiety score were in 11 ~ <16 bus driving years (P <0.05) . Conclusion Bus drivers show special professional personality traits, and some characteristics will be strengthened and weakened with the growth of bus driving experience. It is necessary to carry out special training for the bus drivers with different bus driving experience, especially about dealing with various types of accident risk for new bus driver timely and psychological counseling for old bus driver regularly.

Efficacy analysis of CAPOX regimen and SOX regimen in the treatment of advanced gastric cancer / 中国现代普通外科进展

Objective:To study the effect of CAPOX regimen and SOX regimen in the treatment of advanced gastric cancer.Methods:140 patients with advanced gastric cancer who received chemotherapy from January 2010 to June 2011 in the hospital were enrolled in this study.The patients were divided into observation group (CAPOX regimen) 72 cases and control group(SOX regimen) 68 cases according to the different chemotherapy protocols,two groups were treated with central venous catheter,and in the course of chemotherapy for the given antiemetic,hepatoprotective and Acid suppression related drugs.The observation group was treated with CAPOX regimen,and the control group was treated with SOX regimen,and the 21d was used as the 1 chemotherapy cycle,and the effect was evaluated after 2 cycles of chemotherapy.Results:The effective rate of observation group was 33.33％ (24/72),compared with the control group of 33.82％(23/68),the difference was not statistically significant (P＞0.05).The incidence of hand foot syndrome in the observation group was 16.67％ (12/72),was significantly higher than the control group of 2.94％(2/68),the difference was statistically significant(P＜0.05).The total incidence of adverse reactions in the observation group was 58.33％ (42/72),compared with the control group of 57.35％(39/68),the difference was not statistically significant(P＞0.05).The 1 to 5 year survival rate of the observation group compared with the control group was not statistically significant(P＞0.05).The two groups before and after treatment of CD3+,CD3+CD4+ and CD3+/CD8+ compared,the difference was not statistically significant (P＞0.05).Conclusion:Using CAPOX scheme and the SOX regimen can be better in the treatment of advanced gastric cancer,curative effect and short and long term survival rate was almost equal and influence of immune function of patients with no significant difference,but CAPOX scheme may exist higher hand foot syndrome probability,it is worth clinical optic.

Effects of dexmedetomidine on hypoxia/reoxygenation injury-induced cell apoptosis and caspase-12 expression in A549 cells / 生理学报

To investigate the effects of dexmedetomidine (DEX) on hypoxia/reoxygenation (H/R) injury-induced cell apoptosis and caspase-12 expression, A549 cells were randomly divided into 4 groups: control group, DEX group, H/R group and DEX+H/R group. Cells of control and DEX groups were cultured in the normoxic incubator for 30 h. Cells of H/R and DEX+ H/R groups were incubated in the anoxic cultivation for 6 h, followed by normoxic culture for 24 h, and DEX (1 nmol/L) was added into the culture medium in DEX and DEX+H/R groups. Morphological changes were observed under the inverted microscope. Cell viability was detected by CCK-8. The apoptosis index (AI) of A549 cells was detected by TUNEL method. The activity of caspase-3 enzyme in cells was detected by using caspase-3 kit. The expressions of GRP78, caspase-12 protein and mRNA were determined by Western blot and RT-PCR respectively. Compared with control group, the morphological changes of the cultured cells were observed: some of the cell fusion occurred and the shape of the cells was multilateral; the cell viability was decreased significantly (P < 0.01), the number of apoptotic cells and the AI value, caspase-3 activity, and the expressions of GRP78, caspase-12 protein/mRNA were significantly increased (P < 0.01) in H/R group. While the administration of DEX alleviated the H/R injury-induced cell damage, obviously increased the cell viability (P < 0.01), significantly decreased the increment of apoptotic cells and the AI value induced by H/R injury (P < 0.01), and also dramatically decreased the H/R injury-induced high level of caspase-3 activity (P < 0.01) as well as high expression of caspase-12 protein and mRNA (P < 0.01). Taken together, the results suggest that DEX can effectively protect A549 cells from the H/R injury, which may be mediated by down-regulating the expression of caspase-12 and inhibiting cell apoptosis.

Dynamic changes of IL-1β in rat myocardium during hypoxia/ reoxygenation transition / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the expression profile of interleuki-1β (IL-1β) in rat myocardium at different time points during hypoxia/reoxygenation(H/R)transition.</p><p><b>METHODS</b>The isolated Langendorff perfused rat heart model was established.Forty SD rats were randomly divided into sham group (A group) and hypoxia/reoxygenation group (H/R group). The H/R group rats were subdivided into H/R 0.5 h group(B group), H/R 1 h group(C group), H/R 2 h group(D group)according to reoxygenation time. The left ventricular development pressure(LVDP), maximal rates of increase/decrease of the left ventricular pressure(±dp/dtmax) were continuously recorded. The concentration of interleukin-1β(IL-lβ) and creatine kinase-MB (CK-MB) in myocardium was measured by ELISA. The mRNA expression of IL-lβ in myocardium was determined by RT-PCR. Microstructure of myocardium was observed under light microscopy.</p><p><b>RESULTS</b>The value of LVDP and ±dp/dtmax in hypoxia/reoxygenation group rat were significantly lower than that in sham group(P < 0.05). The expression of IL-lβ and CK-MB at protein level and the expression of IL-1β at mRNA level in hypoxia /reoxygenation group were higher than that in sham group(P < 0. 05). There were significant differences of the above parameters among H/R 0.5 h, 1 h, 2 h group(P <0.05). The concentration of IL-1β and CK-MB, the mRNA expression of IL-1β were higher in H/R 2 h group than that of other groups(P < 0.05).</p><p><b>CONCLUSION</b>The high expression of IL-Iβ in myocardium after myocardial hypoxia /reoxygenation in rats might lead to. ischemia/reperfusion injury.</p>

Enterovirus 71 infecting human brain microvascular endothelial cells: A preliminary study / 第二军医大学学报

Objective To explore the mechanism by which enterovirus71 (EV71) crossing the blood-brain barrier (BBB). Methods BBB models were established by human brain microvascular endothelial cells (HBMECs) in vitro and were randomly assigned to control and EV71-in!ected groups. The cytotoxic effect o! EV71 on HBMECs was examined by morphological observation, immunoflurescence, transmission electron microscope and real-time PCR. In addition, the cytoskeletal alterations in HBMECswere observed by laser confocal method. Results EV71 infection could lead to cytopathic changes of HBMECs. Immunofluorescent staining confirmed the presence of EV71 antigen (red fluorescence) and 20-30 nm EV71 particles in EV71-infected HBMECs, but not in mock infected cells. Viral replication in HBMECs was shown by real-time PCR in a time-dependent manner (P<0. 01). EV71 infected cell lost the normal morphology and polarity, with disarranged actin filaments. Conclusion For the first time we prove that EV71 can infect HBMECs and can replicate in the cells, and can induce cytoskeleton changes in some HBMECs.

Detection of NK and NKT cells in peripheral blood of patients with cGVHD and its significance / 中国实验血液学杂志

The aim of this study was to investigate the correlation of NK and NKT cells in peripheral blood of patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) with chronic graft-versus-host disease (cGVHD). 64 patients undergoing allo-HSCT in Guangdong Provincial People Hospital were studied retrospectively. Among 64 cases, 21 cases were did not develop with cGVHD, 43 cases (mild 15, moderate 18, severe 10) were recorded with cGVHD. The frequency of NK and NKT cells in peripheral blood of patients were measured by flow cytometry. The counts of NK and NKT cells were measured by automatic five sort hematology cyto-analyser (LH-750). The frequency and counts of NK and NKT cells between patients with non-cGVHD and patients with different status of cGVHD were analysed. The results indicated that as compared with the non-cGVHD patients, the frequency and counts of NK cells in patients with cGVHD obviously reduced (P < 0.05), the frequency and count of NKT cells were did not changed significantly. The frequency and counts of NK cells gradually decreased within the different status of cGVHD, the frequency and counts of NK cells in severe-cGVHD were significantly lower than that in mild-cGVHD. It is concluded that NK cells may play an important role in the incidence and development of cGVHD. The detection of frequency and counts of NK cells should be helpful to early diagnose cGVHD and provide valuable clues for assessing the severity of illnesses. NKT cells may have little effect on the incidence and development of cGVHD.

C620R mutation of the murine ret proto-oncogene: loss of function effect in homozygotes and possible gain of function effect in heterozygotes.

Germline RET mutations are responsible for different inherited disorders: Hirschsprung disease (congenital aganglionic megacolon), caused by loss of function mutations, familial medullary thyroid carcinoma and multiple endocrine neoplasia type 2, caused by gain of function mutations. Intriguingly, some RET mutations, including C620R, are associated with both types of diseases. To investigate the dual role of such RET mutations, a mouse model with a targeted mutation ret(C620R) was generated. ret(C620R/C620R) offspring die during the first postnatal day, and show kidney agenesis and intestinal aganglionosis. Decreased outgrowth of the Ret-positive cells was observed in ret(C620R/C620R) neuronal cell cultures, which is suggestive of an impaired migration, proliferation or survival of the Ret-expressing cells. Electronmicroscopy revealed the absence of membrane-bound Ret in ret(C620R/C620R) cells as compared to ret(+/+) and ret(+/C620R) cells. On the other hand, aged ret(+/C620R) mice develop precancerous lesions in the adrenal gland or in the thyroid. Our results suggest that the ret(C620R) mutation has a loss of function effect in homozygotes and exhibits a dominant gain of function effect with low penetrance causing hyperplasia in heterozygotes.

Alpha,beta-poly(N-hydroxypropyl/aminoethyl)-DL-aspartamide -co-L-lysine: potential non-viral vehicle for gene delivery / 生物医学工程学杂志

A series of Poly[aspartic acid-co-L-lysine](PAL) are copolycondensed by DL-aspartice acid and L-lysine with different ratios. Their constructions are identified by the spectra of 1H-NMR, FT-IR, X-Ray). These spectra are proved to have good regularity of these copolymers. alpha,beta-Poly[(N-hydroxypropyl/aminoethyl)-DL-Aspartamide-co-L-lysine] (PHAAL) is synthesized by ring-opening poly [aspartic acid-co-lysine] (PAL). PHAAL has good degradability in the phosphoric acid buffer solution (0.01 M, pH = 7.4) in the enzyme solution (Papain, Trypsine). PHAAL appeared tobe low cytotoxicity in Hela, ECV-304, Bcap37 cell lines, which was quantified by MTT assay. The combination ability of PHAAL with plasmid DNA was evaluated by agarose gel electrophoresis with agarose gel (1.0% w/v) containing ethidium bromide (0.25 microg/ml). The PHAAL with higher ratios of lysine in the copolymers have higher ability of condensing DNA. In summary, PHAAL, the polyaminoacid materials, could be one kind of macromolecule materials tobeused as the non-viral gene vehicle.

Negative regulation of natural killer cell function by EAT-2, a SAP-related adaptor.

EAT-2 is an adaptor expressed in innate immune cells, including natural killer (NK) cells. It is closely related to the adaptor SAP, which regulates signaling lymphocyte activation molecule (SLAM)-related receptors by recruiting the kinase FynT to the receptors. Here we have studied the function of EAT-2 in NK cells by creating mice lacking or overexpressing EAT-2. Like SAP, EAT-2 was associated with the SLAM-related receptor 2B4 in NK cells. However, unlike SAP, EAT-2 was an inhibitor of NK cell function. EAT-2 repressed natural cytotoxicity and interferon-gamma secretion by a mechanism involving tyrosine phosphorylation of its C terminus. We have demonstrated a similar function for the adaptor ERT, a newly identified SAP family member expressed in mouse NK cells. These data identify a previously unknown mechanism of NK cell inhibition. Moreover, they indicate that EAT-2 and SAP have distinct and at times opposing functions in natural immunity.

Regulation of natural cytotoxicity by the adaptor SAP and the Src-related kinase Fyn.

SAP is an adaptor protein that is expressed in NK and T cells. It is mutated in humans who have X-linked lymphoproliferative (XLP) disease. By interacting with SLAM family receptors, SAP enables tyrosine phosphorylation signaling of these receptors by its ability to recruit the Src-related kinase, Fyn. Here, we analyzed the role of SAP in NK cell functions using the SAP-deficient mouse model. Our results showed that SAP was required for the ability of NK cells to eliminate tumor cells in vitro and in vivo. This effect strongly correlated with expression of CD48 on tumor cells, the ligand of 2B4, a SLAM-related receptor expressed in NK cells. In keeping with earlier reports that studied human NK cells, we showed that SAP was necessary for the ability of 2B4 to trigger cytotoxicity and IFN-gamma secretion. In the absence of SAP, 2B4 function was shifted toward inhibition of NK cell-mediated cytotoxicity. By analyzing mice lacking Fyn, we showed that similarly to SAP, Fyn was strictly required for 2B4 function. Taken together, these results provide evidence that the 2B4-SAP-Fyn cascade defines a potent activating pathway of natural cytotoxicity. They also could help to explain the high propensity of patients who have XLP disease to develop lymphoproliferative disorders.

Impaired Ig class switch in mice deficient for the X-linked lymphoproliferative disease gene Sap.

X-linked lymphoproliferative disease (XLP) is characterized by abnormal immune responses to Epstein-Barr virus attributed to inactivating mutations of the SAP gene. Previous studies showed immunoglobulin E (IgE) deficiency and low serum IgG levels in Sap-deficient mice before and after viral infections, which are associated with impaired CD4+ T-helper function. In the present work, we find that signaling lymphocytic activation molecule (SLAM)-associated protein (SAP) is expressed in B cells and this expression is down-regulated after stimulation with lipopolysaccharide (LPS) and interleukin 4 (IL-4). We demonstrate that B cells from Sap-deficient mice exhibit reduced IgG and IgA production in vitro. This impairment correlates with decreased circular transcript levels of Ialpha, Igamma2a, Igamma2b, and Igamma3 after stimulation, which indicate a defective Ig switch recombination in Sap-deficient B cells. While XLP is believed to cause defects in T, natural killer T (NKT), and natural killer (NK) cells, our results indicate that B cells are also affected.

Defective NKT cell development in mice and humans lacking the adapter SAP, the X-linked lymphoproliferative syndrome gene product.

SAP is an adaptor protein expressed in T cells and natural killer cells. It plays a critical role in immunity, as it is mutated in humans with X-linked lymphoproliferative syndrome (XLP), a fatal immunodeficiency characterized by an abnormal response to Epstein-Barr virus (EBV) infection. SAP interacts with the SLAM family receptors and promotes transduction signal events by these receptors through its capacity to recruit and activate the Src kinase FynT. Because it has been previously established that FynT is selectively required for the development of NKT cells, we examined NKT cells in SAP-deficient mice and in humans with XLP. In the absence of SAP, the development of NKT cells is severely impaired both in mice and in humans. These results imply that SAP is a potent regulator of NKT cell development. They also identify for the first time a defect in NKT cells associated with a human primary immunodeficiency, revealing a potential role of NKT cells in the immune response to EBV.

Effect of sour TCM compound recipe on insulin resistance in experimental rats with diabetes mellitus type 2 / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To study the effect of sour TCM compound Recipe (SCCR) on insulin resistance in experimental rats with diabetes mellitus type 2 (DM2), under the guidance of TCM doctrine of "sour restrains sweet".</p><p><b>METHODS</b>Model rats of DM2 were established by 8 weeks' feeding with high calorie forage combined with intraperitoneal injection of small dose of streptozotocin, and treated with SCCR (15 g/kg of crude drug/day). Levels of fasting blood glucose (FBG), serum insulin, free fatty acids (FFA), tumor necrosis factor a (TNF-alpha), combining capacity and constant of insulin receptor in liver were determined before treatment and 4, 8 and 12 weeks after treatment, and the insulin sensitive index was calculated. The data were compared with those in the model group (untreated), sweet TCM compound recipe group and bitter TCM compound group (treated with sweet and bitter Chinese drugs respectively) and the control group (treated with dimethyldiguanide).</p><p><b>RESULTS</b>SCCR could markedly reduce the FBG, serum FFA and TNF-alpha levels in rat model of DM2, stimulate the secretion of insulin, raise the combining capacity and constant of insulin receptor in liver and improve the insulin sensitivity, as compared with the effect of sweet or bitter Chinese compound recipe, the difference was significant (P < 0.05).</p><p><b>CONCLUSION</b>SCCR could improve the glucose metabolic disorder and ameliorate the degree of insulin resistance in DM2 model rats, with the effect superior to those with sweet or bitter taste, which illustrates primarily that the therapeutic principle of "sour restrains sweet" of TCM is true of science in a certain degree and having its guiding significance in clinical practice.</p>

Mice deficient in the X-linked lymphoproliferative disease gene sap exhibit increased susceptibility to murine gammaherpesvirus-68 and hypo-gammaglobulinemia.

X-linked lymphoproliferative disease is characterized by immune dysregulation and uncontrolled lymphoproliferation on exposure to Epstein-Barr virus (EBV). This disease has been attributed to mutations in the SAP gene (also denominated as SH2D1A or DSHP). To delineate the role of SAP in the pathophysiology of X-linked lymphoproliferative disease, a strain of sap-deficient mice has been generated by deleting exon 2 of the gene. After infection with murine gammaherpesvirus-68, which is homologous to EBV, the mutant mice exhibit more vigorous CD8+ T cell proliferation and more disseminated lymphocyte infiltration compared to their wild-type littermates. Chronic tissue damage and hemophagocytosis were evident in sap-deficient mice but not in their wild-type littermates. Concordantly, murine gammaherpesvirus-68 reactivation was observed in sap-deficient mice, indicating an impaired control of the virus. Notably, IgE deficiency and decreased serum IgG level were observed in mutant mice prior to and after murine gammaherpesvirus-68 infection, which reproduces hypo-gammaglobulinemia in X-linked lymphoproliferative disease patients. This mouse model will therefore be a useful tool for dissecting the various phenotypes of X-linked lymphoproliferative disease.

Absence of SLAM mutations in EBV-associated lymphoproliferative disease patients.

X-linked lymphoproliferative disease is a rare inherited immunodeficiency in which affected males present abnormal responses to Epstein-Barr virus (EBV) infection. The gene defective in X-linked lymphoproliferative disease, SH2D1A (also named SAP or DSHP), has been identified and shown to code for an adapter protein that interacts with signaling lymphocytic activation molecule (SLAM) and several other members of the CD2 superfamily. SH2D1A is mutated in no more than 60% of X-linked lymphoproliferative disease patients. It could be postulated that a certain percentage of patients without apparent maternal transmission might be caused by other gene(s) in SH2D1A-related signal transduction pathways. Being a partner of SH2D1A and having a key role in proliferation and differentiation of the T- and B-lymphocytes, SLAM was considered as a candidate gene for patients who manifest symptoms of X-linked lymphoproliferative disease but who have no mutations in SH2D1A. As a first step, SLAM mutations were screened for from cDNA of the lymphoblastoid cell line of all available patients. Then conditions for PCR, single-strand conformational polymorphism (SSCP), heteroduplex analysis, and sequencing were established in all eight exons of SLAM. A total of 31 typical and atypical patients were analysed, from which six novel nucleotide variants were identified; however, none of these variants seems to cause abnormal function of the SLAM gene. Therefore, mutations in coding regions or splicing sites of SLAM are unlikely to play a major role in the mechanism of EBV-associated lymphoproliferation.

A spectrum of mutations in SH2D1A that causes X-linked lymphoproliferative disease and other Epstein-Barr virus-associated illnesses.

X-linked lymphoproliferative disease (Duncan's Disease) was first encountered by David T. Purtilo in 1969. The first communication describing the disease was published in 1975. In 1989 the disease locus was mapped to Xq25. Ten years later the gene (SH2D1A, SAP, DSHP), which is absent or mutated in XLP patients was identified. Since that the protein crystal structure of this small, SH2-domain containing protein has been solved, target molecules of the protein have been identified, physiological and pathological protein/protein interactions have been characterized, and the mouse model of the gene mutation has been developed. That said, a complete understanding of the function of the normal SH2D1A protein in immunoregulation and of the altered immune responses in XLP patients is not yet at hand. Therein lies the legacy of Purtilo's discovery for, as with other primary immunodeficiencies, these "experiments of nature" offer a window on the beauty of the immune system. In due course, the manner by which this gene orchestrates an elegant response (akin to a Mozart divertimento) to EBV infection shall be defined.

Genome-wide search for loss of heterozygosity in Burkitt lymphoma cell lines.

The molecular biological characteristics of Burkitt lymphoma (BL), in addition to the presence of the Epstein-Barr virus (EBV) in some forms, relies on well-characterized alterations, such as MYC translocations and TP53 inactivations. To ascertain the number and location of other genome alterations, we used 191 polymorphic markers in a genome-wide search for loss of heterozygosity (LOH) in 31 Burkitt lymphoma cell lines and their normal counterparts. We were able to distinguish two types of altered allelic patterns: a bona fide LOH profile, indicative of deletion (LOH), and a profile indicative of increased dosage (ID). The former type was most frequent at chromosome arm 17p, most likely indicating TP53 gene inactivation. Increased dosage at 1q was found almost exclusively in non-EBV cell lines (P < 0.00004) and correlated well with karyotypic abnormalities affecting region 1q21-25. Our results suggest that a gene important for BL pathogenesis is located in region 1q21-25 and that the activation of this gene mimics the effects of EBV.