Effect of particulate matter less than 10µm (PM10) on mortality in Bogota, Colombia: a time-series analysis, 1998-2006 / Efecto del material particulado menor a 10µm (PM10) sobre la mortalidad en Bogotá, Colombia: un análisis de series de tiempo 1998-2006

Objective. To analyze the association between daily mortality from different causes and acute exposure to particulate matter less than 10 microns in aerodynamic diameter (PM10), in Bogota, Colombia. Materials and methods. A time-series ecological study was conducted from 1998 to 2006. The association between mortality (due to different causes) and exposure was analyzed using single and distributed lag models and adjusting for potential confounders. Results. For all ages, the cumulative effect of acute mortality from all causes and respiratory causes increased 0.71% (95%CI 0.46-0.96) and 1.43% (95%CI 0.85-2.00), respectively, per 10µg/m³ increment in daily average PM10 with a lag of three days before death. Cumulative effect of mortality from cardiovascular causes was -0.03% (95%CI -0.49-0.44%) with the same lag. Conclusions. The results suggest an association between an increase in PM10 concentrations and acute mortality from all causes and respiratory causes.

Objetivo. Analizar la asociación entre la mortalidad diaria debida a distintas causas y la exposición aguda a partículas menores de 10 micras de diámetro aerodinámico (PM10), en Bogotá, Colombia. Material y métodos. Se realizó un estudio ecológico de series de tiempo (1998-2006). La asociación entre mortalidad y exposición se analizó ajustando modelos de retraso simple y retraso distribuido para diferentes causas de mortalidad. Resultados. En todas las edades, el riesgo acumulado en la mortalidad aguda por todas las causas y causa respiratoria aumentó 0.71% (IC95% 0.46-0.96) y 1.43% (IC95% 0.85-2.00), respectivamente, por incremento de 10µg/m³ en el promedio diario de PM10, tomando un retraso de tres días anteriores al deceso, mientras el riesgo acumulado en la mortalidad por causa cardiovascular fue de -0.03% (IC95% -0.49-0.44), para el mismo retraso. Conclusiones. Los resultados sugieren asociación entre el incremento de las concentraciones de PM10 y la mortalidad aguda por todas las causas y causa respiratoria.

Maintenance of the corneal epithelium is carried out by germinative cells of its basal stratum and not by presumed stem cells of the limbus

The purpose of this investigation was to analyze the proliferative behavior of rabbit corneal epithelium and establish if any particular region was preferentially involved in epithelial maintenance. [3H]-thymidine was injected intravitreally into both normal eyes and eyes with partially scraped corneal epithelium. Semithin sections of the anterior segment were evaluated by quantitative autoradiography. Segments with active replication (on) and those with no cell division (off) were intermingled in all regions of the tissue, suggesting that the renewal of the epithelial surface of the cornea followed an on/off alternating pattern. In the limbus, heavy labeling of the outermost layers was observed, coupled with a few or no labeled nuclei in the basal stratum. This suggests that this region is a site of rapid cell differentiation and does not contain many slow-cycling cells. The conspicuous and protracted labeling of the basal layer of the corneal epithelium suggests that its cells undergo repeated cycles of replication before being sent to the suprabasal strata. This replication model is prone to generate label-retaining cells. Thus, if these are adult stem cells, one must conclude that they reside in the corneal basal layer and not the limbal basal layer. One may also infer that the basal cells of the cornea and not of the limbus are the ones with the main burden of renewing the corneal epithelium. No particular role in this process could be assigned to the cells of the basal layer of the limbal epithelium.

Characterization of Bladder Selectivity of Antimuscarinic Agents on the Basis of In Vivo Drug-Receptor Binding / 대한배뇨장애요실금학회지

The in vivo muscarinic receptor binding of antimuscarinic agents (oxybutynin, solifenacin, tolterodine, and imidafenacin) used to treat urinary dysfunction in patients with overactive bladder is reviewed. Transdermal administration of oxybutynin in rats leads to significant binding of muscarinic receptors in the bladder without long-term binding in the submaxillary gland and the abolishment of salivation evoked by oral oxybutynin. Oral solifenacin shows significant and long-lasting binding to muscarinic receptors in mouse tissues expressing the M3 subtype. Oral tolterodine binds more selectively to muscarinic receptors in the bladder than in the submaxillary gland in mice. The muscarinic receptor binding of oral imidafenacin in rats is more selective and longer-lasting in the bladder than in other tissues such as the submaxillary gland, heart, colon, lung, and brain, suggesting preferential muscarinic receptor binding in the bladder. In vivo quantitative autoradiography with (+)N-[11C]methyl-3-piperidyl benzilate in rats shows significant occupancy of brain muscarinic receptors with the intravenous injection of oxybutynin, solifenacin, and tolterodine. The estimated in vivo selectivity in brain is significantly greater for solifenacin and tolterodine than for oxybutynin. Imidafenacin occupies few brain muscarinic receptors. Similar findings for oral oxybutynin were observed with positron emission tomography in conscious rhesus monkeys with a significant disturbance of short-term memory. The newer generation of antimuscarinic agents may be advantageous in terms of bladder selectivity after systemic administration.

Feasibility of cartilage link protein of hyaluronic acid for defining radiotherapeutic target volume in a mouse model of lung tumor / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the feasibility of using cartilage link protein of hyaluronic acid (HA-CLP) for defining the tumor boundary in a mouse model of lung carcinoma.</p><p><b>METHODS</b>Lung carcinoma was induced in KM mice by chemical carcinogenesis. HA-CLP separated from bovine cartilage and purified by affinity chromatography was labeled with (125)I for autoradiography. Immunohistochemical analysis and Western blotting were used to examine the efficiency of HA-CLP in defining the boundaries of the lung tumors.</p><p><b>RESULTS</b>With autoradiography, the clearest image of lung cancer was obtained at 2 h. With immunohistochemical method, the tumor boundary was the most clearly displayed at 2 h when the strongest signals of HA-CLP was detected; Western blotting also showed the clearest bands of HA-CLP at 2 h.</p><p><b>CONCLUSION</b>HA-CLP has the immunogenicity of HABP, and can efficiently indicate lung tumor boundary in autoradiography and immunohistochemistry.</p>

Rapid Changes in D1 and D2 Dopamine Receptor Binding in Striatal Subregions after a Single Dose of Phencyclidine

OBJECTIVE: In humans, a single exposure to phencyclidine (PCP) can induce a schizophrenia-like psychosis which can persist for up to two weeks. In rats, an acute dose of PCP increases dopaminergic activity and causes changes in dopamine related behaviours some of which are sexually dimorphic. To better understand the effects of PCP on dopamine receptor adaptations in the short term we examined dopamine D1-like receptors (D1R) and D2-like receptors (D2R) in the mesolimbic and nigrostriatal dopamine pathways, 4 hours after exposure to PCP in female rats. METHODS: Animals received a single dose of 40 mg/kg PCP and were sacrificed 4 hours later. In vitro autoradiography was carried out using [3H] SCH 23390 and [3H] raclopride that target D1R and D2R respectively, in cryostat brain sections. RESULTS: Two way analysis of variance (ANOVA), revealed an overall effect of PCP treatment (F [1,63]=9.065; p=0.004) on D1R binding with an 18% decrease (p<0.01) in binding in the medial caudate putamen. PCP treatment also had an overall effect on D2R binding (F [1,47]=5.450; p=0.024) and a trend for an increase in D2R binding across all the brain regions examined. CONCLUSION: These results suggest opposing D1R and D2R adaptations in striatal subregions of female rats following acute exposure to PCP that may occur through indirect mechanisms.

5-Bromo-2’-deoxyuridine induces visible morphological alteration in the DNA puffs of the anterior salivary gland region of Bradysia hygida (Diptera, Sciaridae)

5-Bromo-2’-deoxyuridine (BrdUrd) has long been known to interfere with cell differentiation. We found that treatment ofBradysia hygida larvae with BrdUrd during DNA puff anlage formation in the polytene chromosomes of the salivary gland S1 region noticeably affects anlage morphology. However, it does not affect subsequent metamorphosis to the adult stage. The chromatin of the chromosomal sites that would normally form DNA puffs remains very compact and DNA puff expansion does not occur with administration of 4 to 8 mM BrdUrd. Injection of BrdUrd at different ages provoked a gradient of compaction of the DNA puff chromatin, leading to the formation of very small to almost normal puffs. By immunodetection, we show that the analogue is preferentially incorporated into the DNA puff anlages. When BrdUrd is injected in a mixture with thymidine, it is not incorporated into the DNA, and normal DNA puffs form. Therefore, incorporation of this analogue into the amplified DNA seems to be the cause of this extreme compaction. Autoradiographic experiments and silver grains counting showed that this treatment decreases the efficiency of RNA synthesis at DNA puff anlages.

Neurochemical phenotype and birthdating of specific cell populations in the chick retina

The chick embryo is one of the most traditional models in developing neuroscience and its visual system has been one of the most exhaustively studied. The retina has been used as a model for studying the development of the nervous system. Here, we describe the morphological features that characterize each stage of the retina development and studies of the neurogenesis period of some specific neurochemical subpopulations of retinal cells by using a combination of immunohistochemistry and autoradiography of tritiated-thymidine. It could be concluded that the proliferation period of dopaminergic, GABAergic, cholinoceptive and GABAceptive cells does not follow a common rule of the neurogenesis. In addition, some specific neurochemical cell groups can have a restrict proliferation period when compared to the total cell population.

O embrião de galinha é um dos mais tradicionais modelosde estudos da neurociência do desenvolvimento e seu sistema visual tem sido um dos mais exaustivamente estudado. Aretina tem sido utilizada como modelo para estudar o desenvolvimento do sistema nervoso. Aqui, nós descrevemos as características morfológicas que caracterizam cada estádio da retina em desenvolvimento e os estudos do período de neurogênese de algumas subpopulações de células neuroquímicamente específicas da retina usando uma combinação de imunohistoquímica e autoradiografia de timidina-tritiada. Conclui-se que o período de proliferação das células dopaminérgicas, GABAérgicas, colinoceptivas e GABAceptivas não segue uma regra comum. Além disso, alguns grupos celulares neuroquimicamente distintos podem ter um período de proliferaçãomais restrito quando comparado ao da população total destas células.

Autoradiography observation on cochlea and organs in guinea pigs after intra-abdominal injection of bFGF / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To observe whether bFGF could cross the blood-labyrinth barrier (BLB) after intra-abdominal injection and to establish an experimental basis for its clinical applications.@*METHOD@#Thirty guinea pigs were divided into three groups. Animals in group 1 were administered o I-bFGF, while animals in group 2 and 3 were administered 125 and saline, respectively, via intra-abdominal injection. The both cochlea, blood, liver, brain, thyroid gland and kidney were collected and weighted. A radioimmunoassay analyzer was employed to measure counts per minute (CPM) of each sample, and autoradiography was performed on both cochlea.@*RESULT@#The CPM value of organ samples in the 125I group was higher than that in other groups, and radioactive grain was observed in cochlear samples of this group. In the 125I-bFGF group, blood demonstrated the highest CPM value, while cochlea and brain demonstrated the lowest CPM value, with no radioactive grain observed in cochlear samples.@*CONCLUSION@#bFGF has some difficulties in getting across BLB, so the way of bFGF application in clinics need further study.

Experiencia clínica del uso de la tepoxalina en el tratamiento conservativo de la ruptura del ligamento cruzado craneal en perros / Clinical trial of tepoxalin use in cranial cruciate ligament ruptura conservative treatment in dogs

La ruptura de ligamento cruzado craneal (RLCC) se caracteriza por la laceración parcial o total del ligamento cruzado craneal. Pacientes con laceraciones agudas del ligamento (parcial o total) presentan claudicación aguda con incapacidad total o parcial de sustentación del peso en el miembro afectado. La terapia clínica con principios conservadores debe ser empleada previamente al tratamiento quirúrgico. La tepoxalina es un antiinflamatorio no esteroidal, indicado en la reducción de procesos inflamatorios y alivio del dolor causado por perturbaciones musculo-esqueléticas agudas y crónicas. Este medicamento promueve el bloqueo balanceado de la ruptura del ácido araquidónico por las vías de la lipoxigenasa y cicloxigenasa de la cascada de la inflamación. El presente trabajo tiene por objetivo evaluar la eficacia clínica del uso de la tepoxalina en el tratamiento conservativo de la RLLC, por medio de test clínicos específicos, examen radiográfico y análisis citológico del líquido articular. Diez perros con RLCC, macos y hembras, fueron incluidos en este estudio y recibieron dosis diarias de 10mg/kg de tepoxalina durante veintiocho días. La evaluación de la claudicación, los test de arco de movimiento en extensión máxima y digito-presión, así como el análisis del liquido articular después del periodo de tratamiento, permitieron concluir la efeicacia de la tepoxalina en el tratamiento conservativo de la RLCC. Su uso posibilitó el retorno a la deambulación normal en todos los casos tratados, siendo considerada una opción más de AINE para el tratamiento conservativo de esta artropatía...

Effects on prolactin secretion and binding to dopaminergic receptors in sleep-deprived lupus-prone mice

Sleep disturbances have far-reaching effects on the neuroendocrine and immune systems and may be linked to disease manifestation. Sleep deprivation can accelerate the onset of lupus in NZB/NZWF1 mice, an animal model of severe systemic lupus erythematosus. High prolactin (PRL) concentrations are involved in the pathogenesis of systemic lupus erythematosus in human beings, as well as in NZB/NZWF1 mice. We hypothesized that PRL could be involved in the earlier onset of the disease in sleep-deprived NZB/NZWF1 mice. We also investigated its binding to dopaminergic receptors, since PRL secretion is mainly controlled by dopamine. Female NZB/NZWF1 mice aged 9 weeks were deprived of sleep using the multiple platform method. Blood samples were taken for the determination of PRL concentrations and quantitative receptor autoradiography was used to map binding of the tritiated dopaminergic receptor ligands [³H]-SCH23390, [³H]-raclopride and [³H]-WIN35,428 to D1 and D2 dopaminergic receptors and dopamine transporter sites throughout the brain, respectively. Sleep deprivation induced a significant decrease in plasma PRL secretion (2.58 ± 0.95 ng/mL) compared with the control group (25.25 ± 9.18 ng/mL). The binding to D1 and D2 binding sites was not significantly affected by sleep deprivation; however, dopamine transporter binding was significantly increased in subdivisions of the caudate-putamen - posterior (16.52 ± 0.5 vs 14.44 ± 0.6), dorsolateral (18.84 ± 0.7 vs 15.97 ± 0.7) and ventrolateral (24.99 ± 0.5 vs 22.54 ± 0.7 µCi/g), in the sleep-deprived mice when compared to the control group. These results suggest that PRL is not the main mechanism involved in the earlier onset of the disease observed in sleep-deprived NZB/NZWF1 mice and the reduction of PRL concentrations after sleep deprivation may be mediated by modifications in the dopamine transporter sites of the caudate-putamen.

Autoradiography reporter gene (Ad5-tk carrying HSV1-tk gene) expression imaging in rat myocardium / 中华心血管病杂志

<p><b>OBJECTIVE</b>Radionuclide imaging of reporter gene expression holds promise for noninvasive monitoring of gene therapy. Herpes simplex virus 1-thymidine kinase (HSV1-tk) has been successfully applied to the tumor tissue.We explored the feasibility of the expression imaging of HSV1-tk reporter gene in rat myocardium by using SPECT reporter probe (131)I-2'-fluoro-2'-deoxy-1-beta-D-arabinofuranosyl-5-iodouracil ((131)I-FIAU) and autoradiography (ARG).</p><p><b>METHODS</b>The recombinant Ad5-tk carrying HSV1-tk gene and adenovirus (Ad5-null) as vector were constructed and intramyocardially injected into SD rats. Experiment was grouped for different aims as follows: (1) Influence of time on the imaging after transfection reporter gene: rats were injected with (131)I-FIAU at day 1, 2, 3, 5 and 7 after transfection of 1 x 10(8)pfu Ad5-tk; (2) Influence of various titers on the imaging: rats underwent intramyocardial injection with various titers of Ad5-tk (5 x 10(8), 1 x 10(8), 5 x 10(7), 1 x 10(7)pfu). After 2 days, rats were injected with (131)I-FIAU in tail vein. Equal volume Ad-nulls was intramyocardially injected to control rats. Rats were killed 24 h after injection of (131)I-FIAU and the hearts were rapidly dissected for gamma counts measurement. The total myocardial (131)I-FIAU accumulation was quantified in percent of injected dose per gram myocardium (%ID/g). The myocardial reporter gene expression was semi-quantitatively determined by ARG and RT-PCR.</p><p><b>RESULTS</b>ARG and RT-PCR showed that the local expression of reporter gene increased in proportion with increasing titer and decreased in proportion with time post injection. The semi-quantitative assay showed there were significant correlations among %ID/g, RT-PCR and ARG: r(2) = 0.963, P < 0.05 for RT-PCR and ARG; r(2) = 0.996, P < 0.01 for %ID/g and ARG in rats received various reporter gene titers at identical time point post injection; r(2) = 0.950, P < 0.05 for RT-PCR and ARG; r(2) = 0.980, P < 0.01 for %ID/g and ARG for rats received identical reporter gene titer on various time points post injection.</p><p><b>CONCLUSIONS</b>The present study showed that cardiac reporter gene imaging with HSV1-tk as reporter gene and (131)I-FIAU as reporter probe was feasible in rats. The optimal Ad5-tk titer is 1 x 10(8) pfu and the optimal imaging time is 24 h to 48 h post gene transfer. HSV1-tk/FIAU may be used for the noninvasive monitoring of cardiac gene therapy.</p>

Imaging of Herpes Simplex Virus Type 1 Thymidine Kinase Gene Expression with Radiolabeled 5-(2-iodovinyl)-2'-deoxyuridine (IVDU) in Liver by Hydrodynamic-based Procedure / 핵의학분자영상

PURPOSE: Hydrodynamic-based procedure is a simple and effective gene delivery method to lead a high gene expression in liver tissue. Non-invasive imaging reporter gene system has been used widely with herpes simplex virus type 1 thymidine kinase (HSV1-tk) and its various substrates. In the present study, we investigated to image the expression of HSV1-tk gene with 5-(2-iodovinyl)-2'-deoxyuridine (IVDU) in mouse liver by the hydrodynamicbased procedure. MATERIALS AND METHODS: HSV1-tk or enhanced green fluorescence protein (EGFP) encoded plasmid DNA was transferred into the mouse liver by hydrodynaminc injection. At 24 h post-injection, RT-PCR, biodistribution, fluorescence imaging, nuclear imaging and digital wholebody autoradiography (DWBA) were performed to confirm transferred gene expression. RESULTS: In RT-PCR assay using mRNA from the mouse liver, specific bands of HSV1-tk and EGFP gene were observed in HSV1-tk and EGFP expressing plasmid injected mouse, respectively. Higher uptake of radiolabeled IVDU was exhibited in liver of HSV1-tk gene transferred mouse by biodistribution study. In fluorescence imaging, the liver showed specific fluorescence signal in EGFP gene transferred mouse. Gamma-camera image and DWBA results showed that radiolabeled IVDU was accumulated in the liver of HSV1-tk gene transferred mouse. CONCLUSION: In this study, hydrodynamic-based procedure was effective in liver-specific gene delivery and it could be quantified with molecular imaging methods. Therefore, co-expression of HSV1-tk reporter gene and target gene by hydrodynamic-based procedure is expected to be a useful method for the evaluation of the target gene expression level with radiolabeled IVDU.

Detection of Transferrin Receptor Over-Expression in a Rodent Model of Myocardial Ischemia/Reperfusion Injury Using Novel 99mTc Transferrin Conjugates: A Pilot Study

BACKGROUND AND OBJECTIVES: Reperfusion of ischemic myocardium is necessary to salvage tissue from eventual death. However, new pathophysiological changes are initiated after reperfusion. The aim of this study was to investigate one of the mechanisms of ischemia/reperfusion (I/R) injury, and we focused on transferrin. MATERIALS AND METHODS: Male Spragre-Dawley (SD) rats were used for the I/R model. Myocardial ischemia was produced by occlusion of the left anterior descending coronary artery for 30 minutes. 99mTc Transferrin-Chitosan-hydrazino nicotinate hydrochloride (HYNIC) (Tfc) (/37 MBq/mL) was injected once after the reperfusion was finished. Autoradiography, hematoxylin and eosin (H & E) staining and determination of the tissue myeloperoxidase (MPO) activity were performed. RESULTS: Autoradiography showed remarkable 99mTc-Tfc uptake in the left ventricular myocardium at the reperfusion period from 0 to 1.5 hours, whereas no uptake was demonstrated at 3 hours. The uptake was increased again at 6 and 24 hours. Western blotting showed that the transferrin receptor (TfR) proteins were increased at 0 to 1.5 hours compared with that of the control; this expression of TfR disappeared at 3 hours, and it showed up for the second time at 6 and 24 hours. The MPO activity only at 24 hours was significantly higher than that of the control and those MPO activities at 0 to 6 hours (p=0.001). CONCLUSION: In the rodent model of 30 minutes occlusion and reperfusion, our study revealed, with using 99mTc-Tfc, that the TfR expression increased in the myocardium till 3 hours after reperfusion. TfR-mediated entry of iron into the cardiomyocytes may represent that this process plays a role in the I/R injury during the early reperfusion period.

Clinical research of AFP variant with microcentrifugalcolumn method and crossed affinity immunoelectrophoresis autoradiography method / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To compare the clinical value of microcentrifugalcolumn method with crossed affinity immunoelectrophoresis autoradiography method for the measurement of alpha-fetoprotein variant (AFP-L3) in differentiation of benign and malignant liver.</p><p><b>METHODS</b>Serum AFP-L3 variants in 102 primary hepatocellular carcinoma patients and 41 chronic and cirrhosis patients were separated by microcentrifugalcolumn method and crossed affinity immunoelectrophoresis autoradiography method and the clinical value of both method were compared.</p><p><b>RESULTS</b>In 102 primary hepatocellular carcinoma patients, the sensitivity of AFP-L3 was 79.4% and 91.2% respectively, in 41 chronic and cirrhosis patients. The specificity of AFP-L3 was 70.7% and 29.3% respectively. The diagnostic accuracy was 76.9% and 73.4% respectively. The area in the ROC curve was 0.791 and 0.758 respectively. In the 4 primary hepatocellular carcinoma patients with lower AFP-L3, the AFP-L3 was positive by useing microcentrifugalcolumn method, but none of AFP-L3 were found by useing crossed affinity immunoelectrophoresis autoradiography method.</p><p><b>CONCLUSION</b>The micro centrifugalcolumn method is more simple and rapid, it may be more useful in differentiation of benign and malignant liver than traditional crossed affinity immunoelectrophoresis autoradiography method.</p>

Molecular mechanism of epididymal protease inhibitor modulating the liquefaction of human semen / 亚洲男科学杂志(英文版)

<p><b>AIM</b>To study the molecular mechanism of epididymal protease inhibitor (Eppin) modulating the process of prostate specific antigen (PSA) digesting semenogelin (Sg).</p><p><b>METHODS</b>Human Sg cDNA (nucleotides 82-849) and Eppin cDNA (nucleotides 70-723) were generated by polymerase chain reaction (PCR) and cloned into pET-100D/TOPO. Recombinant Eppin and Sg (rEppin and rSg) were produced by BL21 (DE3). The association of Eppin with Sg was studied by far-western immunoblot and radioautography. In vitro the digestion of rSg by PSA in the presence or absence of rEppin was studied. The effect of anti-Q20E (N-terminal) and C-terminal of Eppin on Eppin-Sg binding was monitored.</p><p><b>RESULTS</b>Eppin binds Sg on the surface of human spermatozoa with the C-terminal of Eppin (amino acids 75-133). rSg was digested with PSA and many low molecular weight fragments were produced. When rEppin is bound to rSg, then digested by PSA, incomplete digestion and a 15-kDa fragment results. Antibody binding to the N-terminal of rEppin did not affect rSg digestion. Addition of antibodies to the C-terminal of rEppin inhibited the modulating effect of rEppin.</p><p><b>CONCLUSION</b>Eppin protects a 15-kDa fragment of rSg from hydrolysis by PSA.</p>

Drosophila simulans Lethal hybrid rescue mutation (Lhr) rescues inviable hybrids by restoring X chromosomal dosage compensation and causes fluctuating asymmetry of development.

The Drosophila simulans Lhr rescues lethal hybrids from the cross of D. melanogaster and D. simulans. We describe here, the phenotypes of Lhr dependent rescue hybrids and demonstrate the effects of Lhr on functional morphology of the salivary chromosomes in the hybrids. Our results reveal that the phenotypes of the 'Lhr dependent rescued' hybrids were largely dependent on the genetic background and the dominance in species and hybrids, and not on Lhr. Cytological examination reveal that while the salivary chromosome of 'larval lethal' male carrying melanogaster X chromosome was unusually thin and contracted, in 'rescued' hybrid males (C(mel)X(mel)Y(sim); A(mel)A(sim)) the X chromosome showed typical pale staining, enlarged diameter and incorporated higher rate of (3)H-uridine in presence of one dose Lhr in the genome. In hybrid males carrying simulans X chromosome (C(mel)X(sim)Y(mel); A(mel)A(sim)), enlarged width of the polytene X chromosome was noted in most of the nuclei, in Lhr background, and transcribed at higher rate than that of the single X chromosome of male. In hybrid females (both viable, e.g., C(mel)X(mel)X(sim); A(mel)A(sim) and rescued, e.g., C(mel)X(mel)X(mel); A(mel)A(sim)), the functional morphology of the X chromosomes were comparable to that of diploid autosomes in presence of one dose of Lhr. In hybrid metafemales (C(mel)X(mel)X(mel)X(sim); A(mel)A(sim)), two dose of melanogaster X chromosomes and one dose of simulans X chromosome were transcribed almost at 'female' rate in hybrid genetic background in presence of one dose of Lhr. In rescued hybrid males, the melanogaster-derived X chromosome appeared to complete its replication faster than autosomes. These results together have been interpreted to have suggested that Lhr suppresses the lethality of hybrids by regulating functional activities of the X chromosome(s) for dosage compensation.

No changes in densities of cannabinoid receptors in the superior temporal gyrus in schizophrenia / 神经科学通报·英文版

<p><b>OBJECTIVE</b>In recent years, abnormal changes in the endocannabinoid system have been found in schizophrenia. The superior temporal gyrus (STG) is strongly implicated in the pathophysiology of schizophrenia, particularly with regards to auditory hallucinations. In this study, we investigated the binding density of cannabinoid CB1 receptors in the STG of schizophrenia patients compared to control subjects.</p><p><b>METHODS</b>Quantitative autoradiography was used to investigate the binding densities of [(3)H]SR141716A (a selective antagonist) and [(3)H]CP-55940 (an agonist) to the CB1 receptors in the STG. Post-mortem brain tissue was obtained from the NSW Tissue Resource Centre (Australia).</p><p><b>RESULTS</b>Contrasting to previous findings in the alterations of CB1 receptor densities in the prefrontal, anterior and posterior cingulate cortex of schizophrenia, which were suggested to be associated to impairment of cognition function, no significant difference was found between the schizophrenia and control cases in both [(3)H]SR141716A and [(3)H]CP-55940 binding.</p><p><b>CONCLUSION</b>We suggest that CB1 receptors in the STG are not involved in the pathology of schizophrenia and the auditory hallucination symptom of this disease.</p>

Transferrin receptor imaging for tracing mesenchymal stem cells implanted in the spinal cord / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the feasibility of tracing mesenchymal stem cells in vivo with scintigraphy.</p><p><b>METHODS</b>Transferrin receptor expression of cultured mesenchymal stem cells (hMSCs) was quantified with radioligand-receptor binding assay before the cells were transplanted into the spinal cord of rabbits. (131)I-labeled transferrin was then administered into the subarachnoid space of the rabbits, and scintigraphic images were acquired with a gamma camera at different time points after the administration. In the control experiments, (131)I-labeled human serum albumin was used in stead of (131)I-transferrin as the tracer, or only PBS was injected without stem cell transplantation. The images were semi-quantitatively analyzed with region of interest (ROI) techniques, and the phosphor imaging on the spinal sections were performed.</p><p><b>RESULTS</b>Radioligand-receptor binding assay showed 10 770 binding sites with high affinity (KD=0.982 nmol/L) for Fe saturated transferrin on each human mesenchymal cell. Visible accumulation of radioactivity at the cell transplantation sites was observed 16 h and 24 h after intrathecal injection of (131)I-transferrin tracer, but not in two control groups. ROI analysis showed that the difference between (131)I-transferrin and the control groups was statistically significant (P<0.05). Phosphor imaging further verified that it was the specific coupling of transferrin to the implanted cells that resulted in radioactivity accumulation at the transplantation sites.</p><p><b>CONCLUSIONS</b>Transferrin receptor imaging is capable of in vivo tracing of the implanted stem cells, and has the potential for use in non-invasive monitoring for stem cell transplantation therapy after further technical improvements.</p>

Optimization of RQRT-pCR protocols to measure beta-1,3-glucanase mRNA levels in infected tissues of rubber tree (Hevea brasiliensis).

RQRT-PCR technique was evaluated for its validity as an alternative to Northern blotting for quantification of plant gene expression in diseased tissues of Hevea. Reliable RT-PCR results could be obtained by co-amplification of housekeeping actin gene as the internal control along with the gene of interest. The product of interest was quantified relative to that of the internal control by measuring net intensity of bands. Expression levels of defense-related beta-1,3-glucanase gene was studied in the pathogen infected tissues of rubber. The beta-1,3-glucanase gene was found to be induced in infected leaf tissues and reached a peak at 48 h after inoculation. The beta-1,3-glucanase gene expression during pathogen infection was determined through Northern blot hybridization also, using 18S RNA as the internal control. RQRT-PCR and Northern hybridization showed almost similar results, thereby validating the use of this technique to study the gene expression in rubber.

Expression of opioid receptor-like 1 (ORL1) & mu opioid receptors in the spinal cord of morphine tolerant mice.

BACKGROUND & OBJECTIVE: The mechanism underlying the development of tolerance to morphine is not clearly understood though a number of factors have been implicated. One of the likely factors may be increased activity of anti-opioid peptides like nociceptin (also known as orphanin FQ or N/OFQ). N/OFQ and morphine bind to opioid receptor-like 1 (ORL1) receptor and muopioid receptor respectively. The present work was undertaken to investigate the density of ORL1 and mu (mu) receptor expression in the spinal cord of mice after inducing morphine tolerance. METHODS: Swiss albino mice were injected with either morphine (experimental group, n=15) or saline (control, n=15), twice a day for 9 days. The development of tolerance was noted by the hotplate test. Cryostat sections of the cervical region of spinal cord were labeled with specific ligands to localize ORL1 and mu receptors. The density of receptor expression over laminae I-II of spinal cord was evaluated using image analysis system. RESULTS: The morphine treated mice developed tolerance by day 9 as evident by the hot plate test. Both receptors were selectively expressed at a higher concentration over the superficial laminae (I-II) of the dorsal horn, indicating a role in pain processing. An increased expression of ORL1 receptors was also noted over the gray matter around the central canal. Quantitative analysis showed an increased expression of ORL1 and mu receptors though the increase was not statistically significant. INTERPRETATION & CONCLUSION: The present study showed that both, ORL1 and mu-opioid receptors were expressed in areas of the spinal cord, concerned with transmission of pain signals. The density of these receptors increased in the superficial laminae (I-II) though not significantly from control after morphine tolerance. The increase in ORL1 receptors could oppose the analgesic action of morphine, contributing to tolerance. Further studies need to be done to elucidate the mechanism of morphine tolerance.