A polymorphism within interleukin-21 receptor (IL21R) confers risk for systemic lupus erythematosus and is associated with malar rash in lupus patients (49.17)

Interleukin (IL) 21 is a member of the type I cytokine superfamily that exerts a variety of effects on the immune system including B cell activation, plasma cell differentiation, and immunoglobulin production. The IL21 receptor (IL21R) is expressed on B cells, T cells, NK cells, and monocyte-derived dendritic cells. The expression of IL21R is reduced in B cells from lupus patients, while IL21 serum levels are increased in both lupus patients and some lupus-murine models. We recently reported that polymorphisms within the IL21 gene are associated with increased susceptibility to lupus. Herein, we genotyped SNPs in the IL21R gene located on chromosome 16p11. We identify and confirm the association between rs3093301 and lupus in two independent European-derived and Hispanic cohorts (p=7.2X10-5). In addition, the presence of the homozygous risk genotype in rs3093301 (A/A) was associated with the development of malar rash in the European-derived female lupus patients (OR=2.83, 95% CI=1.56-5.13, p=0.00045).

C8orf13/BLK association with systemic lupus erythematosus across different ethnicities (136.28)

SLE is a complex autoimmune disease with immunological abnormalities that targets B cell functions and development. Previous genome-wide association studies identified C8orf13/BLK as a novel SLE risk factor. BLK (B lymphoid tyrosine kinase) has been shown to have potential effects on B cell develoment. The main objectives of this study are to: 1.) assess this association in independent populations and 2.) determine if BLK risk alleles correlate with alteration in peripheral blood B cell development and protein expression. We genotyped 52 SNPs within the C8orf13/BLK region in European-derived, Asian and African American populations. rs13277113 is associated with SLE in all three populations. A few novel upstream SNPs within the intergenic region demonstrate a stronger association in Asians. Flow cytometry data suggests there is a significant difference in BLK expression and T2 cells B cell numbers between high-risk and non-risk individuals based on the risk haplotype. Our results suggest that the BLK genetic polymorphisms alter immune system development and function to increase the risk for SLE development. Supported by NIH RR020143, RR015577, NIAID-DAIT-BAA-05-11, AI031584, AR053483, AR48940, AI063274, AR052125, AR043247 and OCAST # HR08-037.

Empyema thoracis

OBJECTIVE

To review the management of Empyema Thoracis in the surgical department of Kathmandu Medical College Teaching Hospital.

METHODS

Thirteen cases with Empyema thoraces treated in the surgical department of the hospital with different modalities of treatment was taken for study and analyzed for morbidity, mortality, and hospital stay.

RESULTS

there was a single mortality in the thoracotomy group. Video assisted thoracic surgery or VATS debridement or deloculation was successful in the eight of the patients with shorter stay in the hospital. One patient who refused surgery was treated with streptokinase with good result.

CONCLUSION

Streptokinase may be effective in the treatment of empyemas. Video assisted thoracic surgery or VATS has definite advantage over traditional surgery in terms decreased morbidity, mortality, earlier hospital discharge and cosmesis in the treatment of empyema.

Cell adhesion by aqueous extract of human placenta used as wound healer

Aqueous extract of human placenta, used as wound healer, has shown significant cell adhesion property on mouse peritoneal macrophages and P388D1 cultured macrophage cell line. This property was offered primarily by fibronectin type III like peptide present in the extract and is comparable to fibronectin on a molar basis. The peptide induce adhesion of cell through cell surface receptors having K(d) = 2.8 +/- 0.9 x 10(-5) M suggesting weak binding. This is in support of integrins receptors that typically exhibit low affinities. Cell adhesion was partially inhibited by Arg-Gly-Asp (RGD) peptide, anti-beta1 integrin suggesting that integrin beta1 receptors have roles to play in the process.

New liver cell mutants defective in the endocytic pathway

To isolate mutant liver cells defective in the endocytic pathway, a selection strategy using toxic ligands for two distinct membrane receptors was utilized. Rare survivors termed trafficking mutants (Trf2-Trf7) were stable and more resistant than the parental HuH-7 cells to both toxin conjugates. They differed from the previously isolated Trf1 HuH-7 mutant as they expressed casein kinase 2 alpha'' (CK2alpha'') which is missing from Trf1 cells and which corrects the Trf1 trafficking phenotype. Binding of (125)I-asialoorosomucoid (ASOR) and cell surface expression of asialoglycoprotein receptor (ASGPR) were reduced approximately 20%-60% in Trf2-Trf7 cells compared to parental HuH-7, without a reduction in total cellular ASGPR. Based on (125)I-transferrin binding, cell surface transferrin receptor activity was reduced between 13% and 88% in the various mutant cell lines. Distinctive phenotypic traits were identified in the differential resistance of Trf2-Trf7 to a panel of lectins and toxins and to UV light-induced cell death. By following the endocytic uptake and trafficking of Alexa(488)-ASOR, significant differences in endosomal fusion between parental HuH-7 and the Trf mutants became apparent. Unlike parental HuH-7 cells in which the fusion of endosomes into larger vesicles was evident as early as 20 min, ASOR endocytosed into the Trf mutants remained within small vesicles for up to 60 min. Identifying the biochemical and genetic mechanisms underlying these phenotypes should uncover novel and unpredicted protein-protein or protein-lipid interactions that orchestrate specific steps in membrane protein trafficking.

Kif5B and Kifc1 interact and are required for motility and fission of early endocytic vesicles in mouse liver

Early endocytic vesicles loaded with Texas Red asialoorosomucoid were prepared from mouse liver. These vesicles bound to microtubules in vitro, and upon ATP addition, they moved bidirectionally, frequently undergoing fission into two daughter vesicles. There was no effect of vanadate (inhibitor of dynein) on motility, whereas 5'-adenylylimido-diphosphate (kinesin inhibitor) was highly inhibitory. Studies with specific antibodies confirmed that dynein was not associated with these vesicles and that Kif5B and the minus-end kinesin Kifc1 mediated their plus- and minus-end motility, respectively. More than 90% of vesicles associated with Kifc1 also contained Kif5B, and inhibition of Kifc1 with antibody resulted in enhancement of plus-end-directed motility. There was reduced vesicle fission when either Kifc1 or Kif5B activity was inhibited by antibody, indicating that the opposing forces resulting from activity of both motors are required for fission to occur. Immunoprecipitation of native Kif5B by FLAG antibody after expression of FLAG-Kifc1 in 293T cells indicates that these two motors can interact with each other. Whether they interact directly or through a complex of potential regulatory proteins will need to be clarified in future studies. However, the present study shows that coordinated activity of these kinesins is essential for motility and processing of early endocytic vesicles.

Mandibular reconstruction

One of the most difficult problem in reconstructive surgery is the replacement of lost bone from trauma, tumour, infection or congenital anomaly. This is a case report of a 20 year old male who had suffered a blast injury of his lower jaw. From his first admission in the Plastic unit of Bir Hospital on Feb 19, 2003, he had undergone multiple operations until Nov 2003. This is a description of a follow up surgery done in Kathmandu Medical College (KMC), Sinamangal. Difficulties encountered and options available have also been discussed.

PKCzeta is required for microtubule-based motility of vesicles containing the ntcp transporter

Intracellular trafficking regulates the abundance and therefore activity of transporters present at the plasma membrane. The transporter, Na+-taurocholate co-transporting polypeptide (ntcp), is increased at the plasma membrane upon treatment of cells with cAMP, for which microtubules (MTs) are required and the PI3K pathway and PKCzeta have been implicated. However, trafficking of ntcp on MTs has not been demonstrated directly and the regulation and intracellular localization of ntcp is not well understood. Here, we utilize in vitro and whole-cell immunofluorescence microscopy assays to demonstrate that ntcp is present on intracellular vesicles that bind MTs and move bidirectionally, using kinesin-1 and dynein. These vesicles co-localize with markers for recycling endosomes and early but not late endosomes. They frequently undergo fission, providing a mechanism for the exclusion of ntcp from late endosomes. PI(3,4,5)P3 activates PKCzeta and enhances motility of the ntcp vesicles and overcomes the partial inhibition produced by a PI3-kinase inhibitor. Specific inhibition of PKCzeta blocks the motility of ntcp-containing vesicles but has no effect on late vesicles as shown both in vitro and in living cells transfected with ntcp-GFP. These data indicate that PKCzeta is required specifically for the intracellular movement of vesicles that contain the ntcp transporter.

Transactivation of the epidermal growth factor receptor by cag+ Helicobacter pylori induces upregulation of the early growth response gene Egr-1 in gastric epithelial cells

BACKGROUND AND AIMS

Helicobacter pylori, in particular cytotoxin associated gene (cag)+ strains, have been shown to enhance gastric epithelial cell proliferation in vivo, an effect that likely contributes to gastric carcinogenesis. Early growth response gene 1 (Egr-1) is a crucial regulator of cell growth, differentiation, and survival, which is known to play a role in carcinogenesis and cancer progression. The aims of this study were to: (1) examine whether H pylori could upregulate Egr-1 in gastric epithelial cell lines; (2) determine whether there was a differential response to infection with different strains; (3) examine the role of the cag pathogenicity island in this process; and (4) elucidate the molecular mechanisms leading to Egr-1 upregulation.

METHODS AND RESULTS

We found that infection of AGS cells with cag+H pylori resulted in a rapid (1-2 hours) but transient increase in Egr-1 mRNA and protein levels whereas coculture with cag- isolates did not elicit this response. Furthermore, two independent cagE- isogenic mutants of H pylori also demonstrated impaired ability to upregulate Egr-1. Upregulation of Egr-1 protein was inhibited by the extracellular regulated kinase (ERK)1/2 inhibitor PD98059 and overexpression of dominant negative MEK1 downregulated Egr-1 luciferase reporter gene activity. Treatment of AGS cells with the epidermal growth factor receptor (EGFR) kinase inhibitors PD153035 and AG1478 resulted in a reduction in H pylori mediated Egr-1 upregulation, demonstrating that EGFR transactivation plays a role in this early cellular process.

CONCLUSIONS

Our findings show that cag+H pylori cause rapid induction of Egr-1 in gastric epithelial cells which may contribute to H pylori mediated pathogenesis.

Odontogenic origin of necrotizing fasciitis of head and neck - a case report

Necrotizing fasciitis (NF) of head and neck is a fulminant infection associated with necrosis of connective tissue which spreads along the fascial planes with high mortality rate. It is usually polymicrobial, odontogenic and occurs more frequently in immunocompromised patients. Because of the rarity of the disease, early diagnosis and early management is often delayed. We present a diabetic patient who developed NF of head and neck following tooth extraction. Because of vigorous teamwork he could be saved from the fatal disease but required extensive plastic repair. Every clinician should be aware of such a disease, particularly in immunocompromised patients and necessitates earliest diagnosis and intervention to save their life.

KEYWORDS

Necrotizing fasciitis, necrotizing soft tissue infections.

Outcome of Treatment of Alcohol Dependence Syndrome Patients in Military Psychiatry Set Up

BACKGROUND

Many people believe that patients suffering from Alcohol Dependence Syndrome do not respond much to treatment. Such belief may adversely affect the treatment of these patients. This may also alter the attitude of administrators on disposal of these patients. In this study, an attempt was made to observe the treatment outcome of patients suffering from Alcohol Dependence Syndrome.

METHOD

Medical documents of all patients suffering from Alcohol Dependence Syndrome who reported for follow up in a general hospital psychiatric centre during the period of 1995-2000, were scrutinized. Patients were divided into three categories - those who were in relapse, those who improved partially and those who maintained abstinence.

RESULTS

Out of 341 cases, 146 patients were reviewed after six months, 57 after one year, 50 after one and half years and 88 were reviewed at 2 years and above. When a total was made about the number of relapses, partial improvement and abstinent cases, it was found that 33.16% had relapses, 35.49% cases showed partial improvement and 31.35% cases were abstinent.

CONCLUSION

The result was contrary to a prevailing belief that these patients do not respond much to treatment. It showed that two third of the patients improved, out of which one third were abstinent at the time of review. This study is likely to encourage the doctors, patients and administrative authorities to seek treatment of patients suffering from Alcohol Dependence Syndrome as treatment definitely helps many of them.

Microtubule-dependent movement of late endocytic vesicles in vitro: requirements for Dynein and Kinesin

Our previous studies demonstrated that fluorescent early endocytic vesicles prepared from rat liver after injection of Texas red asialoorosomucoid contain asialoglycoprotein and its receptor and move and undergo fission along microtubules using kinesin I and KIFC2, with Rab4 regulating KIFC2 activity (J. Cell Sci. 116, 2749, 2003). In the current study, procedures to prepare fluorescent late endocytic vesicles were devised. In addition, flow cytometry was utilized to prepare highly purified fluorescent endocytic vesicles, permitting validation of microscopy-based experiments as well as direct biochemical analysis. These studies revealed that late vesicles bound to and moved along microtubules, but in contrast to early vesicles, did not undergo fission. As compared with early vesicles, late vesicles had reduced association with receptor, Rab4, and kinesin I but were highly associated with dynein, Rab7, dynactin, and KIF3A. Dynein and KIF3A antibodies inhibited late vesicle motility, whereas kinesin I and KIFC2 antibodies had no effect. Dynamitin antibodies prevented the association of late vesicles with microtubules. These results indicate that acquisition and exchange of specific motor and regulatory proteins characterizes and may regulate the transition of early to late endocytic vesicles. Flow cytometric purification should ultimately facilitate detailed proteomic analysis and mapping of endocytic vesicle-associated proteins.

Electron transfer interaction of dihydroxyquinones with amine quenchers: dependence of the quenching kinetics on the aliphatic and aromatic nature of the amine donors

Studies on the electron transfer (ET) interaction of 1,4-dihydroxy-9,10-anthraquinone and 6,11-dihydroxy-5,12-naphthacenequinone with aliphatic and aromatic amine (AlA and ArA, respectively) donors have been investigated in acetonitrile solutions. Steady-state (SS) measurements show quenching of the quinone fluorescence by amines, without indicating any change in the shape of the fluorescence spectra. No significant change in the absorption spectra of the quinones is also observed in the presence of the amines. For all the quinone-amine pairs, the bimolecular quenching constants (kq) estimated from SS and time-resolved measurements are found to be similar. Variation in the kq values with the oxidation potentials of the amines indicates the involvement of the ET mechanism for the quenching process. A reasonably good correlation between the kq values and the free energy changes (deltaG0) for the ET reactions following Marcus' outer-sphere ET theory also supports this mechanism. It is seen that for both the quinone-ArA and quinone-AlA systems, the kq values initially increase and then get saturated at some diffusion-controlled limiting values (kqDC) as deltaG0 values gradually become more negative. Interestingly, however, it is seen that the kqDC value for the quinone-AlA systems is substantially lower than that for quinone-ArA systems. Such a large difference in the kqDC values between quinone-AlA and quinone-ArA systems is quite unusual. Present results have been rationalized based on the assumption that an orientational restriction is imposed for the encounter complexes in quinone-AlA systems to undergo ET reactions, which arises because of the localized (at amino nitrogen) shapes of the highest-occupied molecular orbitals (HOMO) of AlA in comparison to the pi-like HOMO of the ArA.

Chromosome aberrations in de novo acute myeloid leukemia patients in Kuwait

Cytogenetic analysis was successfully performed at the time of diagnosis in 45 patients with de novo acute myeloid leukemia, including 10 children and 35 adults. In approximately 73% of AML patients (35 patients) clonal chromosome abnormalities were detected at the time of diagnosis. Twelve patients (22.8%) had apparently normal karyotypes. Recurring aberrations found in 22 of patients with abnormal karyotypes included t(15;17)(q22;q11), t(8;21)(q22;q22), inv(16)(p13q22), trisomy 8, monosomy 7 and del(5q). The highest frequency of chromosome changes was observed in AML-M3. The occurrence of the classical cytogenetic abnormalities was not a ubiquitous phenomenon. In 11 patients previously not described miscellaneous clonal chromosomal abnormalities were detected. Clonal chromosomal abnormalities detected in AML have shown correlations between specific recurrent chromosomal abnormalities and clinico-biological characteristics of the patients, therefore have been repeatedly shown to constitute markers of diagnostic and prognostic significance. Moreover, ongoing cytogenetic analysis can identify new nonrandom chromosome aberrations in AML and contribute to the identification of novel genes involved in the development of cancer, which can lead to better understanding of the disease pathogenesis.

Anteversion of the femoral neck in Indian dry femora

The purpose of this study was to estimate the average angle of femoral neck anteversion in an Indian population. A total of 300 dry femora were classified by standard anatomical norms into male and female types and left-side and right-side types. They were evaluated by the Kingsley Olmsted and parallelograph methods, and the data were statistically analyzed. The average angles of anteversion obtained were 8.1 degrees and 8.3 degrees by the Kingsley Olmsted and parallelograph methods, respectively. The average female-type bone showed about 3 degrees more anteversion than the male-type bone. The average left-sided bone showed about 1.6 degrees more anteversion than the right-sided bone. A statistically significant difference existed between the sexes and the sides. The Kingsley Olmsted and parallelograph methods were found to be comparable with a correlation coefficient of 0.99. Altogether, 42.33%, 57.66%, and 79.00% of bones had readings of 5 degrees -10 degrees, 0 degrees -10 degrees, and 0 degrees -15 degrees, respectively. Thus, femoral neck anteversion has been found to be less in the Indian population than in Western populations.

Extended application of gel-permeation chromatography by spin column

Separation of small volumes of proteins from unbound ligands or reequilibration with buffer by passing through a 1-ml Sephadex G-50 column under mild centrifugal force is a popular technique. Here it has been demonstrated that other Sephadex matrix could similarly be used for complete or partial separation of protein molecules. Proteins to be eluted at void volume are recovered near quantitatively, while others are partly or almost completely retained depending on molecular size. Calibration curves using standard proteins of Mw 12.5 to 440 kDa with Sephadex G-50-G-200 representing recovery versus molecular weight show profiles as expected from the fractionation ranges of the column matrix. The procedure may be applied to follow protein association-dissociation reactions if the molecular weights of the species concerned are known and a proper matrix exists for separating them. Equilibrium unfolding transitions constructed with model proteins in presence of 0-8M urea using recovery as an index correspond to profiles obtained from other physical measurements. This may be a convenient approach to follow change of protein hydrodynamic volume quickly when a parallel methodology is not readily available.

Role of calcium in acute hyperthermic myocardial injury

INTRODUCTION

We hypothesized that intracellular calcium overload may play an important role in heat-induced myocardial injury. This postulate was investigated using a model of isolated guinea pig papillary muscle in which resting tension was measured as an indirect indicator of cytosolic free-calcium concentration and the fluorescence changes of Fluo-3 AM dye was measured as a direct indicator of cytosolic free-calcium concentration.

METHODS AND RESULTS

Excised guinea pig right ventricular papillary muscles were attached to a force transducer in a high-flow tissue bath and superfused with Tyrode's solution at 37 degrees +/- 0.5 degrees C. The temperature was rapidly changed to between 38.0 degrees and 56.0 degrees C for 60 seconds and then returned to 37.0 degrees C. Hyperthermia caused a reversible increase in resting tension at temperatures between 45 degrees and 50 degrees C and irreversible contracture at > or =50 degrees C. Rapid cooling contracture experiments and experiments measuring fluorescence of myocytes loaded with 5 microM Fluo-3 AM dye demonstrated that the hyperthermia-induced rise in resting tension was likely due to an increase in intracellular calcium content. Inhibition of the sarcoplasmic reticulum calcium pump with 20 microM thapsigargin resulted in irreversible contracture of the papillary muscles at temperatures between 45 degrees and 50 degrees C and significant increases in Fluo-3 fluorescence at 48 degrees C. Blockade of sarcolemmal calcium channels with 0.5 mM cadmium or 40 microM verapamil did not attenuate the heat-induced increase in resting tension and Fluo-3 fluorescence.

CONCLUSION

Hyperthermia causes an increase in resting tension of cardiac muscle that most likely is mediated by a calcium channel-independent increase in calcium permeability of the sarcolemmal membrane and/or release of stored intracellular calcium.

A metadata framework for interoperating heterogeneous genome data using XML

The rapid advances in the Human Genome Project and genomic technologies have produced massive amounts of data populated in a large number of network-accessible databases. These technological advances and the associated data can have a great impact on biomedicine and healthcare. To answer many of the biologically or medically important questions, researchers often need to integrate data from a number of independent but related genome databases. One common practice is to download data sets (text files) from various genome Web sites and process them by some local programs. One main problem with this approach is that these programs are written on a case-by-case basis because the data sets involved are heterogeneous in structure. To address this problem, we define metadata that maps these heterogeneously structured files into a common eXtensible Markup Language (XML) structure to facilitate data interoperation. We illustrate this approach by interoperating two sets of essential yeast genes that are stored in two yeast genome databases (MIPS and YPD).