[Analysis of perioperative blood loss of posterior lumbar interbody fusion on lumbar spondylolisthesis in patients with rheumatoid arthritis].

Objective: To compare the intraoperative blood loss, postoperative drainage and hidden blood loss (HBL) in lumbar posterior lumbar interbody fusion (PLIF) in patients with and without rheumatoid arthritis (RA), and analyze the relevant factors of HBL in RA patients. Methods: Fifty patients with RA (RA group) and 73 patients without RA (NRA group) treated in the Heze Municipal Hospital from January 2014 to April 2019 were enrolled in this study. The basic information, RA information, operation and related blood loss indicators in the two groups were compared. The intraoperative blood loss, postoperative drainage and HBL were the main results. The secondary results were operation time, preoperative and postoperative hematocrit (Hct) and hemoglobin (Hb) and their variation values, cases of anemia before and after surgery, number of new anemia after surgery, autologous blood and allogeneic blood transfusion, etc. The correlation factors of HBL in RA group were analyzed by multi-linear regression model. Results: There were 9 males and 41 females with a mean age of (62±7) years in RA group; and 11 males and 62 females with a mean age of (64±9) years in NRA group. The course of disease in RA group was (14.4±11.2) years, the most common anti-rheumatism drug (DMARDs) were single-drug and combined oral. There was no significant differences between the two groups in the number of vertebral bow screws and intervertebral fusion device. The incidence of surgical complications was comparable between the two groups. Differences between the two groups in total blood loss (TBL), intraoperative blood loss, and postoperative drainage were not statistically significant ((693±315) ml vs (630±365) ml, (454±373) ml vs (414±375) ml and (653±376) ml vs (675±400) ml, t=1.072, 0.388, -0.189, all P>0.05), while the HBL and the percentage of HBL in TBL were lower in the NRA group (t=6.157, 2.965, both P<0.05). According to the layered analysis of the number of surgical segments, the proportion of HBL and the HBL percentage of TBL in the NRA group for the long section (≥3 segments) surgery were better than those in the RA group. The Hct changing value was larger in the RA group than that in the NRA group (P=0.031). However, the difference of Hb reduction between the two groups was not statistically significant (P>0.05). There was no significant difference in anemia and exacerbation of anemia after surgery, allogeneic blood transfusion and the operation duration between the two groups (all P>0.05). A multi-linear regression analysis of HBL showed that higher RA's Steinbrocker grading, did not take DMARDS, Hb changes and infusion of allogeneic blood were independently correlated to HBL (ß=0.363, -0.272, 0.210, 1.204, all P<0.05). Conclusions: There is no difference in TBL, intraoperative blood loss, postoperative drainage and operation duration between the RA and NRA group, while HBL and the proportion of HBL in the TBL are higher in the RA group. The RA group has higher Steinbrocker rating, no DMRDs and more Hb changes.

Purulent pericarditis, multi-site abscesses and ketoacidosis in a patient with newly diagnosed diabetes: a rare case report.

BACKGROUND: Purulent pericarditis is an acute and fulminant disease characterized by pus accumulation in the pericardial space. Its incidence has declined substantially and the common pathogen has changed since the beginning of the antibiotic era; however, it is still found in some patients with immunocompromised conditions. CASE REPORT: We report a rare case in which the onset of diabetes mellitus presented as extremely high HbA1c concentration, ketoacidosis, multi-site abscesses and purulent pericarditis. After antibiotic therapy and pericardiocentesis, the purulent pericarditis still did not resolve and further intrapericardial thrombolytic therapy also failed. Finally, this patient was treated successfully by surgical debridement and pericardiectomy. CONCLUSION: In the immunocompromised state of severe hyperglycaemia, purulent pericarditis is a possible complication of uncontrolled infection. If purulent pericarditis cannot be cured using non-surgical treatments, such as antibiotic therapy, pericardiocentesis and intrapericardial thrombolytic therapy, a surgical pericardiectomy should be considered to avoid morbidity and mortality.

Stable transfection and identification of a hair follicle-specific expression vector of IGFBP-5 in goat fetal fibroblasts.

The insulin-like growth factor-binding protein-5 (IGFBP-5) is one of the 6 members of the IGFBP family and is involved in the regulation of cell growth, apoptosis, and other IGF-stimulated signaling pathways. To determine the significance of IGFBP-5 in the Inner Mongolia Cashmere goat (Capra hircus), a hair follicle-specific expression vector of IGFBP-5, pCDsRed2-K-IGFBP5 (6.7 kb), was constructed by cloning IGFBP-5 downstream of the keratin-association protein (KAP)6-1 promoter and inserting this fragment into pCDsRed2, which contains a red fluorescent protein (DsRed) expression unit. Inner Mongolia Cashmere goat fetal fibroblast (GFb) cells were transfected with the expression vector by using Lipofectamine(TM) 2000. Cell clones that stably expressed red fluorescence were obtained after selection with Geneticin (G418). The transgene in the cell clones was examined by polymerase chain reaction to verify that exogenous DNA (pKAP6-1 and IGFBP-5) had integrated stably into GFb cells. These data suggest that this method can be used for the construction of a hair follicle-specific expression vector for functional genetic analyses and for obtaining stable transfection donor cells for nuclear transfer.

The A1166C polymorphism of angiotensin II Type 1 receptor as a predictor of renal function decline over 4 years follow-up in an apparently healthy Chinese population.

AIM: The angiotensin II Type 1 receptor (AT1R) A1166C (rs5186) genez polymorphism is equivocally associated with the patients' susceptibility to chronic kidney disease or end-stage renal disease. We conducted a prospective study to investigate the influence of AT1R A1166C gene polymorphism on the quantitative changes of renal function. METHOD: Of 1500 people screened, 112 non-diabetic normotensive elderly Chinese were recruited and received biochemistry examination at the baseline, at the second and fourth year follow-up. Serum creatinine and calculated renal parameters, using Cockroft-Gault (CG) formula, Modification of Diet in Renal Disease (MDRD) Study and abbreviated MDRD (abMDRD) equation, were used to evaluate renal function and their progression. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism. RESULT: Age was 71.9 +/- 3.7 years (range 60 - 81). Serum creatinine, CG creatinine clearance (CrCl), MDRD and abMDRD glomerular filtration rate (GFR) were significantly decreased at the 2 and 4-year follow-up (all p < 0.001). The magnitude of 4-year decline of above four renal parameters was significantly higher in subjects carrying the AT1R AA genotype than C-allele carriers (p = 0.014, 0.033, 0.008 and 0.014 for creatinine, CG CrCl, MDRD and abMDRD GFR, respectively). This association was still significant in multivariate analyses (p = 0.019, 0.045, 0.035 and 0.018, respectively). CONCLUSION: This longitudinal study showed that the aging process was associated with decline of renal function in the healthy elderly. The AT1R A1166C gene polymorphism might modulate these changes in the Chinese. This provides further knowledge essential in the assessment of renal disease and determination of renal function in the older subjects.

Peroxisomal straight-chain Acyl-CoA oxidase and D-bifunctional protein are essential for the retroconversion step in docosahexaenoic acid synthesis.

Docosahexaenoic acid (DHA, C22:6n-3) is essential for normal brain and retinal development. The nature and subcellular location of the terminal steps in DHA biosynthesis have been controversial. Rather than direct Delta4-desaturation of C22:5n-3, it has been proposed that this intermediate is elongated to C24:5n-3, desaturated to C24:6n-3, and "retroconverted" to DHA via peroxisomal beta-oxidation. However, this hypothesis has recently been challenged. The goal of this study was to determine the mechanism and specific enzymes required for the retroconversion step in human skin fibroblasts. Cells from patients with deficiencies of either acyl-CoA oxidase or D-bifunctional protein, the first two enzymes of the peroxisomal straight-chain fatty acid beta-oxidation pathway, exhibited impaired (5-20% of control) conversion of either [1-14C]18:3n-3 or [1-14C]22:5n-3 to DHA as did cells from peroxisome biogenesis disorder patients comprising eight distinct genotypes. In contrast, normal DHA synthesis was observed in cells from patients with rhizomelic chondrodysplasia punctata, Refsum disease, X-linked adrenoleukodystrophy, and deficiency of mitochondrial medium- or very long-chain acyl-CoA dehydrogenase. Acyl-CoA oxidase-deficient cells accumulated 2-5 times more radiolabeled C24:6n-3 than did controls. Our data are consistent with the retroconversion hypothesis and demonstrate that peroxisomal beta-oxidation enzymes acyl-CoA oxidase and D-bifunctional protein are essential for this process in human skin fibroblasts.

The peroxisome deficient PEX2 Zellweger mouse: pathologic and biochemical correlates of lipid dysfunction.

Zellweger syndrome is the prototypic human peroxisomal biogenesis disorder that results in abnormal neuronal migration in the central nervous system and severe neurologic dysfunction. A murine model for this disorder was previously developed by targeted deletion of the PEX2 peroxisomal gene. By labeling neuronal precursor cells in vivo with a mitotic marker, we can demonstrate a delay in neuronal migration in the cerebral cortex of homozygous PEX2 mutant mice. Postnatal PEX2 Zellweger mice develop severe cerebellar defects with abnormal Purkinje cell development and an altered folial pattern. When the PEX2 mutation is placed on an inbred murine genetic background, there is significant embryonic lethality and widespread neuronal lipidosis throughout the brain. Biochemical analysis of PEX2 mutant mice shows the characteristic accumulation of very long chain fatty acids and deficient plasmalogens in a wide variety of tissues. Docosahexaenoic acid levels (DHA; 22:6n-3) were found to be reduced in the brain of mutant mice but were normal in visceral organs at birth. All tissues examined in postnatal mutant mice had reduced DHA. The combined use of morphologic and biochemical analyses in these mice will be essential to elucidate the pathogenesis of this complex peroxisomal disease.

Fetal baboons convert 18:3n-3 to 22:6n-3 in vivo. A stable isotope tracer study.

Using [13C]-tracers and direct fetal doses, we show for the first time that the fetal primate converts alpha-linolenic acid (18:3) to docosahexaenoic acid (22:6) in vivo, and we estimate the relative bioefficacy of the two substrates for brain 22:6 accretion. Pregnant female baboons consumed a diet free of long chain polyunsaturates (LCP), with n-6/n-3 ratio of 10/1. In the third trimester of pregnancy (normal gestation = 182 days), they were instrumented with chronic indwelling catheters in the maternal femoral artery and the fetal jugular artery. Doses of either [U-13C]-18:3 (18:3*, n = 3) or [U-13C]-22:6 (22:6*, n = 2) were administered directly to the fetus. Blood was collected from fetus and mother, and the fetus was taken by cesarean section when electromyographic activity indicated that parturition was imminent. Fetal liver, brain, retina, and retinal pigment epithelium (RPE) were collected, and (13)C fatty acids determined. In 18:3*- dosed animals, labeled n-3 LCP were detected in fetal plasma at 1 day post-dose and peaked at 2;-3 days; brain 22:6* was constant at 3, 5, and 9 days post-dose, at 0.57 +/- 0.03 percent of dose (%Dose). In 22:6*- dosed animals, brain 22:6* was similar at 3 and 9 days post-dose (4.64 +/- 0.43%Dose). From these data, we estimate that preformed 22:6 in the fetal bloodstream is 8-fold more efficacious for brain 22:6 accretion than is 18:3. Retina 22:6* was stable at about 0.0008%Dose from 3 to 9 days in 18:3-dosed animals, but RPE 22:6* dropped over the period; brain results were consistent with these observations. Liver showed about 0.5%Dose in 22:6* and in intermediary n-3 fatty acid metabolites 20:5* and 22:5* at 3 days post-dose, and declined afterward. Back-transfer of labeled fatty acids to the maternal bloodstream was measurable but not sufficient to compromise the quantitative conversion data in fetuses. We conclude 1) primate fetuses have the capacity to convert 18:3 to 22:6 in vivo; 2) fetal brain 22:6* as %Dose plateaus by 3 days post-dose; 3) fetal plasma 22:6 is about 8-fold more effective as a substrate for brain 22:6 accretion compared with 18:3; and 4) the fetal liver is likely to be an important site of 18:3 to 22:6 conversion.

Temperature effect on nervous necrosis virus infection in grouper cell line and in grouper larvae.

This preliminary study elucidates the in vitro and in vivo effects of temperature on grouper nervous necrosis virus (GNNV) infection. A novel continuous cell line derived from the fin tissue of a grouper (Epinephelus coioides, Hamilton), named as GF-1 cell line, was used. Cytopathic effect was observed in GNNV-infected GF-1 cells incubated at 24-32 degrees C after viral adsorption, but not at 20 degrees C or 37 degrees C even though the viral adsorption temperature was 28 degrees C. Viral protein could be detected in the pellets of GNNV-infected GF-1 cells cultured at 20-32 degrees C, but not at 37 degrees C. In a challenge test, GNNV-challenged larvae which were maintained at a constant 28 degrees C began to die 1 day post challenge (p.c.) with a death rate of 80%. Mortality reached 100% by 50 h p.c., while the mortality of negative control fish was only 5%. The cumulative mortality of GNNV-challenged larvae at ambient temperature, i.e. 28 degrees C at noon and 24 degrees C at midnight, was 10% 1 day p.c., and increased to 100% by 80 h p.c. Based on the results, we concluded that temperature plays an important role in GNNV infection and pathogenicity.

Dietary 18:3n-3 and 22:6n-3 as sources of 22:6n-3 accretion in neonatal baboon brain and associated organs.

The bioequivalence of dietary linolenic acid (LNA) and docosahexaenoic acid (DHA) for brain DHA accretion was measured in neonatal baboons at 4-6 wk of age using stable isotope tracers. Neonates consumed a conventional U.S. term-infant formula devoid of long chain polyunsaturates and with an n-6/n-3 ratio of about 10:1. At 4 wk of age, neonates were dosed with either 13C LNA or 13C DHA. At 6 wk of age, neonate brain, retina, and other organs were harvested for fatty acid and isotopic analyses. The relative accretion of labeled DHA was 7-fold greater as a percentage of dose for the DHA-dosed animals compared to the LNA-dosed animals. The baboon is an omnivore that regularly consumes meat and insects; its plasma lipid profile responds similarly to humans in response to changes in feeding and living habits. These observations suggest that the baboon is a suitable model for human unsaturated fatty acid studies.

Linoleic acid kinetics and conversion to arachidonic acid in the pregnant and fetal baboon.

Linoleic acid plasma kinetics in pregnant baboons and its conversion to long chain polyunsaturates (LCP) in fetal organs is characterized over a 29-day period using stable isotope tracers. Pregnant baboons consumed an LCP-free diet and received [U-13C]linoleic acid (18:2*) in their third trimester of gestation. In maternal plasma, 18:2* dropped to near baseline by 14 days post-dose, while labeled arachidonic acid (20:4*) plateaued at 10 days at about 70% of total labeled fatty acids. After 2;-5 days, total tracer fatty acids decreased in visceral organs, but increased in the fetal brain. Maximal fetal incorporation of 18:2* was 1;-2 days post-dose; thereafter it dropped while 20:4* increased reciprocally. Labeled 20:4 replaced 18:2* in neural tissues by 5 days post-dose. In liver, kidney, and lung, 20:4* became dominant by 12 days, but in heart the crossover was >29 days. Fetal brain 20:4* plateaued by 21 days at 0. 025% of dose, while fetal liver 20:4* was constant from 1 to 29 days at 0.006% of dose. Under these dietary conditions we estimate that the fetus derives about 50% its 20:4 requirement from conversion of dietary 18:2, with the balance from maternal stores, and conclude that 1) fetal organs accumulate 18:2 within a day of a maternal dose and convert much of it to 20:4 within weeks, 2) modest dietary 18:2 levels may support fetal brain requirements for 20:4, and 3) the brain retains n;-6 fatty acids uniquely compared with major visceral organs.

Bioequivalence of dietary alpha-linolenic and docosahexaenoic acids as sources of docosahexaenoate accretion in brain and associated organs of neonatal baboons.

The dietary bioequivalence of alpha-linolenic (LNA) and docosahexaenoic acids (DHA) as substrates for brain and retinal n-3 fatty acid accretion during the brain growth spurt is reported for neonatal baboons who consumed a long-chain-polyunsaturate free commercial human infant formula with a n-6/n-3 ratio of 10:1. Neonates received oral doses of 13C-labeled fatty acids (LNA*) or (DHA*) at 4 wk of age, and at 6 wk brain (occipital cortex), retina, retinal pigment epithelium, liver, erythrocytes, and plasma were analyzed. In the brain, 1.71% of the preformed DHA* dose was detected, whereas 0.23% of the LNA* dose was detected as DHA*, indicating that preformed DHA is 7-fold more effective than LNA-derived DHA as a source for DHA accretion. In LNA*-dosed animals, DHA* was greater than 60% of labeled fatty acids in all tissues except erythrocytes, where docosapentaenoic acid was 55%. Estimates using dietary LNA levels as tracees indicate that brain turnover of DHA is less than 5% per week between weeks 4 and 6 of life. For retina and retinal pigment epithelium, preformed DHA was at levels 12-fold and 15-fold greater than LNA-derived DHA. Liver, plasma, and erythrocytes ratios were 27, 29, and 51, respectively, showing that these pools do not parallel tissue metabolism of a single dose of omega-3 fatty acids. The distributions of labeled fatty acids for LNA*-dosed animals were similar, in the order DHA > DPA > EPA > LNA, except for erythrocytes where docosapentaenoic acid predominated. These are the first direct measurements of the bioequivalence of DHA and LNA in neonatal primate brain and associated tissues.

Simultaneous measurement of desaturase activities using stable isotope tracers or a nontracer method.

We report here methods for simultaneous determination of in vitro desaturase activities using stable isotope tracers or using a nontracer method in place of radiotracers. Rat microsomal Delta6- and Delta9-desaturase activities were assayed using standard incubation medium by monitoring the increase in product due to the reactions [U-13C]18:2n-6 --> [U-13C]18:3n-6 or [U-13C]16:0 --> [U-13C]16:1n-7, respectively. The stable isotope measurements were made by high-precision gas chromatography-combustion isotope ratio mass spectrometry. Reaction-dependent changes in product or substrate concentrations were also monitored quantitatively by conventional capillary gas chromatography with flame-ionization detection. Desaturase activities calculated from these data are consistent with tracer results. Microsomal Delta5-desaturase activity was monitored by quantifying the decrease in unlabeled substrate mass using the reaction 20:3n-6 --> 20:4n-6. All activities showed the expected dependencies on time, temperature, pH, and microsome and substrate concentrations and were well within the range of published activities. Activities in brain, liver, kidney, and heart microsome preparations measured with either labeled or nonlabeled substrate were not significantly different, but were highly significantly different from organ to organ. These methods demonstrate a means to measure desaturase activities conveniently without radiotracers and for reactions involving substrates which are not available in labeled form.

Increasing dietary linoleic acid in young rats increases and then decreases docosahexaenoic acid in retina but not in brain.

The accumulation of fatty acids in retina, brain, liver, and plasma of 30-day-old rat pups consuming various levels of linoleic acid (LA, 18:2n-6) and constant alpha-linolenic acid (ALA, 18:3n-3) is reported. Dams were fed graded levels of LA during gestation and lactation, and the pups were maintained on the diet of their dams until the end of the brain growth spurt at 30 d of life. Milk, and pup brain, retina, liver, and plasma were analyzed quantitatively for fatty acid profile. The percentage of docosahexaenoic acid (DHA, 22:6n-3) in retina increased from an LA-deficient dietary level, peaked at the 9:1 (LA/ALA) level, then fell for the 41:1 and 69:1 levels. In contrast, the brain DHA percentage was unaffected by dietary LA levels. Retinal unsaturated fatty acid levels paralleled liver and plasma levels. The milk fatty acid composition mirrored the diets. These data show that the retinal fatty acid composition responds sensitively to dietary fatty acid composition, similar to liver and plasma, while the brain unsaturate composition is nearly independent of dietary composition.

Genomic organization and sequence conservation in type I Trichomonas vaginalis viruses.

To reveal the genetic conservation of type I Trichomonas vaginalis viruses (TVV) we cloned and sequenced the 4.6-kb ds RNA of a TVV-T5 isolate for comparison with the cDNA sequence of a related TVV-T1 ds RNA. Analogous to TVV-T1, the TVV-T5 ds RNA also contains an upstream capsid protein gene overlapped with a downstream RNA-dependent RNA polymerase (RDRP) gene by a +1 reading frame shift. A conserved ribosomal slippage heptamer (C CUU UUU) was found within the consensus 14-nt overlap, and the context of the sequence surrounding the heptamer suggests a potential ribosomal frameshifting in the biosynthesis of RDRP from the initiation of capsid protein either through two consecutive -1 shifts or a +1 shift.

Conversion of alpha-linolenate to docosahexaenoate is not depressed by high dietary levels of linoleate in young rats: tracer evidence using high precision mass spectrometry.

The conversion of alpha-linolenate (18:3n-3) to docosahexaenoate (22:6n-3) in the presence of low and high dietary levels of linoleate (18:2n-6) is reported in young rats using [U-13C]-alpha-linolenic acid (18:2n-3*) and high precision gas chromatography-combustion isotope ratio mass spectrometry (GCC-IRMS). After consuming an 18:3n-3-deficient diet for 4 weeks, dams were bred and assigned to one of three diet groups: a) 2 g 18:3n-3/kg diet and 17 g 18:2n-6/kg diet (Lo-18:2), b) 2 g 18:3n-3/kg diet and 140 g 18:2n-6/kg diet (Hi-18:2), or c) essential fatty acid-deficient diet (EFAD). Pups were weaned to the maternal diets. At 42 days of age, pups were gavaged with 1 mg 18:3n-3*, and killed 48 h later. Fatty acid composition of liver reflected the diets to a greater extent than did the brain, and 22:5n-6 replaced 22:6n-3 in the brain. About 80% of the label in liver, brain, and plasma was found as 22:6n-3* for the replete groups. The enrichment pattern was similar in liver and plasma except for 18:3n-3, which was higher in liver. Total label detected was 4-fold higher in the EFAD livers and 2-fold higher in the EFAD brains than in the other groups, which were indistinguishable. Conversion of 18:3n-3* to 22:6n-3* was greater in livers from the Hi-18:2 group than from the Lo-18:2 group (P < 0.05). Estimates of overall label recovery in liver and brain were consistent with literature values. These data indicate that high dietary levels of 18:2n-6 do not inhibit conversion of a single dose of 18:3n-3 to 22:6n-3 in young rats, and demonstrate the applicability of high precision GCC-IRMS to fatty acid tracer studies.

The divergence of Trichomonas vaginalis virus RNAs among various isolates of Trichomonas vaginalis.

Trichomonas vaginalis virus is a double-stranded (ds) RNA virus found in the parasitic protozoan T. vaginalis. To examine the possible existence of related viruses in various T. vaginalis strains and isolates, we screened 20 such isolates and found the characteristic 5.5-kb viral ds RNA in 16 of them. An additional 0.5-kb ds RNA band was also identified in 10 of these virus-infected T. vaginalis isolates. In a local isolate T1, this 0.5-kb ds RNA cross-hybridized with the 5.5-kb ds RNA. Preliminary evidence from CsCl buoyant density gradient centrifugations suggests that the two ds RNA species are encapsidated in separate viral particles by the same capsid protein. The 5.5-kb ds RNA in isolate T1 exhibited moderate hybridization with the prototype 5.5-kb ds RNA in T. vaginalis stratin NIH-Cl. Little cross-hybridization was observed among the 5.5-kb ds RNAs from T. vaginalis isolates JH32A No. 4, T1 and T5, although the viral proteins in these isolates are of similar molecular weight and share common epitopes as viewed by Western blotting. Hybridization characteristics of the 5.5-kb ds RNAs in individual isolates were further analyzed, and the results suggest great ds RNA divergence among the T. vaginalis viruses. Interestingly, the 0.5-kb ds RNA in different isolates of T. vaginalis also exhibited divergence in patterns closely associated with that of the 5.5-kb ds RNA.

Giardiavirus enters Giardia lamblia WB trophozoite via endocytosis.

As part of our continuing effort in the study of Giardiavirus life cycle, the early events of Giardia lamblia virus (GLV) infection in the trophozoites of G. lamblia WB strain were examined. Electron microscopy showed that GLV particles were initially localized on plasma membrane. As time progresses, GLV was translocated to the peripheral vacuole and then spread to the cytoplasm. Inhibitors of endocytosis such as sodium azide, chloroquine, or ammonium chloride disrupted viral infection when the drug was added simultaneously with the infecting GLV. The inhibitory effect was reduced when sodium azide or chloroquine was added at various intervals after infection. When cells infected for 1 hr were examined by immunofluorescence staining, sodium azide greatly reduced GLV staining signal in general while chloroquine restricted the staining signal to a few bright spots. Significantly more GLV was found in the peripheral vacuoles of chloroquine-treated cells than untreated controls by semiquantitative electron microscopy. In contrast, only a reduced amount of GLV was found in the peripheral vacuoles of sodium azide-treated cells. These results suggest that sodium azide reduces the internalization of infecting GLV, while chloroquine confines the virus in the peripheral vacuoles and, consequently, leads to nonproductive infection. We conclude from these observations that the entry of GLV into the susceptible WB cells in the event of infection is most likely mediated by endocytosis.