Complete genome sequence of Moraxella sp. strain DOX410, a bacterium potentially degrading 1,4-dioxane isolated from river sediment

Moraxella sp. strain DOX410 was isolated from a systematic enrichment culture to investigate strains with 1,4-dioxane degradation potential. The genome of strain DOX410 consists of five complete contigs and contained genes related to degradation of the aromatic ring structure of 1,4-dioxane.

Quantifying heat stress; the roles on metabolic status and intestinal integrity in poultry, a review

Heat stress adversely affects intestinal barrier integrity ranging from minor enterocyte injury to fatal inflammatory heat shocks. The current review discusses the physiological mechanisms of the adaptive response of poultry and the nutritional interventions to improve intestinal integrity during heat stress. There are several possible metabolic mechanisms of protection including stress adaptation signaling pathways, blood flow, intestinal barrier permeability, epithelial cell proliferation, antioxidant status, microbiota composition, expression of heat shock proteins, inflammatory responses, and energy metabolism. The current review discusses the methods of intestinal permeability determination in order to estimate the extent of damage in the farm. There is a lack of knowledge about the nutritional strategies and the interaction between nutrients to reduce intestinal barrier damage and elucidate mechanisms in heat stress.

Companilactobacillus pabuli sp. nov., a lactic acid bacterium isolated from animal feed

A Gram-positive, facultative anaerobic, catalase-negative, non-motile, non-spore-forming and rod-shaped lactic acid bacterium strain, denoted as NFFJ11^T and isolated from total mixed fermentation feed in the Republic of Korea, was characterized through polyphasic approaches, including sequence analyses of the 16S rRNA gene and housekeeping genes (rpoA and pheS), determination of average nucleotide identity and in silico DNA-DNA hybridization, fatty acid methyl ester analysis, and phenotypic characterization. Phylogenetic analyses based on 16S rRNA, rpoA and pheS gene sequences revealed that strain NFFJ11^T belonged to the genus Companilactobacillus. The 16S rRNA gene sequence of strain NFFJ11^T exhibited high similarity to Companilactobacillus formosensis S215^T (99.66 %), Companilactobacillus farciminis Rv4 na^T (99.53 %), Companilactobacillus crustorum LMG 23699^T (99.19 %), Companilactobacillus futsaii YM 0097^T (99.06 %), Companilactobacillus zhachilii HBUAS52074^T (98.86 %) and Companilactobacillus heilongiiangensis S4-3^T (98.66 %). However, average nucleotide identity and in silico DNA-DNA hybridization values for these type strains were in the range of 79.90-92.93 % and 23.80-49.30 %, respectively, which offer evidence that strain NFFJ11^T belongs to a novel species of the genus Companilactobacillus. The cell-wall peptidoglycan type was A4α (l-Lys-d-Asp) and the G+C content of the genomic DNA was 35.7 mol%. The main fatty acids of strain NFFJ11^T were C_18 : 1  ω9c (43.3 %), C_16 : 0 (20.1 %) and summed feature 7 (18.3 %; comprising any combination of C_19 : 1  ω7c, C_19 : 1  ω6c and C_19 : 0 cyclo ω10c). Through polyphasic taxonomic analysis, it was observed that strain NFFJ11^T represents a novel species belonging to the genus Companilactobacillus, for which the name Companilactobacillus pabuli sp. nov. is proposed. The type strain is NFFJ11^T (= KACC 21771^T= JCM 34088^T).

Synthesis of carboxymethylated nanocellulose fabricated ciprofloxacine - Montmorillonite composite for sustained delivery of antibiotics

Montmorillonite (MMT) is a highly promising material for use in drug delivery due to its high drug loading capacity and controlled drug release properties. MMT protects drug molecules between layered structure; however, drug release from MMT is sustained less than 6 h, which is insufficient for the release of antibiotics. This study sought to synthesize an antibiotic delivery material with more sustained release properties. A ciprofloxacin (CIP)-MMT composite was fabricated using carboxymethylated nanocellulose (CMCNF). A simple adsorption reaction intercalated 31.1% of CIP molecules present into the MMT under optimized conditions (pH 5, CIP = 1000 mg/L, Reaction time = 3 h). The synthesized CIP-MMT composite was fabricated using 1.5, 2, or 3 wt% CMCNF. Increasing the CMCNF content delayed the erosion of the CMCNF matrix and prevented rapid dissolution of the CIP-MMT composite. In vitro release experiments revealed that the CIP-MMT composite material provided the sustained release of CIP over 6 h. Erosion of the 3 wt% CMCNF-CIP-MMT composite occurred slowly and provided 48 h of sustained CIP release. An anti-bacterial test revealed that the 3 wt% CMCNF-CIP-MMT composite displayed the most constant antibacterial activity over 12 days. These results demonstrated that the CMCNF prepared with CIP intercalation in MMT was highly effective in prolonging the antibiotic release.

Initial results from the New Horizons exploration of 2014 MU69, a small Kuiper Belt object

The Kuiper Belt is a distant region of the outer Solar System. On 1 January 2019, the New Horizons spacecraft flew close to (486958) 2014 MU₆₉, a cold classical Kuiper Belt object approximately 30 kilometers in diameter. Such objects have never been substantially heated by the Sun and are therefore well preserved since their formation. We describe initial results from these encounter observations. MU₆₉ is a bilobed contact binary with a flattened shape, discrete geological units, and noticeable albedo heterogeneity. However, there is little surface color or compositional heterogeneity. No evidence for satellites, rings or other dust structures, a gas coma, or solar wind interactions was detected. MU₆₉'s origin appears consistent with pebble cloud collapse followed by a low-velocity merger of its two lobes.

A pilot study of planar coil based magnetic stimulation using acute hippocampal slice in mice

Micromagnetic stimulation using small-sized implantable coils has recently been studied. The main advantage of this method is that it can provide sustainable stimulation performance even if a fibrotic encapsulation layer is formed around the implanted coil by inflammation response, because indirectly induced currents are used to induce neural responses. In previous research, we optimized the geometrical and control parameters used in implantable magnetic stimulation. Based on those results, we fabricated the planar coil and studied the LTP effect in the hippocampal slice by two different magnetic stimulation protocols using the quadripulse stimulation (QPS) pattern. We found that direct magnetic stimulation (DMS) induced insignificant LTP effect and priming magnetic stimulation (PMS) occluded LTP effect after tetanic stimulation, when QPS patterned magnetic stimulation with 1 A current pulse was applied to the planar coil.

Effects of stock density on the laying performance, blood parameter, corticosterone, litter quality, gas emission and bone mineral density of laying hens in floor pens

The effects of stocking density on the performance, egg quality, leukocyte concentration, blood biochemistry, corticosterone levels, bone mineral density, and noxious gas emission of laying hens were investigated. Eight hundred 34-week-old Hy-Line Brown laying hens (Gallus gallus domesticus) were randomly assigned to one of 4 treatments, each of which was replicated 4 times. Four stocking densities, including 5, 6, 7, and 10 birds/m2, were compared. A commercial-type basal diet was formulated to meet or exceed nutrient recommendations for laying hens from the National Research Council. The diet was fed to the hens ad libitum for 8 wk. Results indicated that hen-day egg production, egg mass, and feed intake were less for (P < 0.01) 10 birds/m2 stock density than other stock densities. Production rate of floor and broken eggs and eggshell strength were greater (P < 0.01) for 10 birds/m2 stock density than other stock densities. There were no significant differences in the level of leukocytes among densities. However, heterophils and the H/L ratio were greater (P < 0.01) for 10 birds/m2 than in stock density of 6 or 7 birds/m2 Serum corticosterone was greater (P < 0.01) 10 birds/m2 than stock density than other stock densities. Litter moisture and gas emission (CO2 and NH3) were greater (P < 0.01) for 10 birds/m2 than stock density than 6 and 7 birds/m2 stock density. Bone mineral content was not influenced by increasing stock density. However, bone mineral density was less (P < 0.05) for 10 m2 stock density than other stock densities. These results indicate that increasing the density beyond 5 birds/m2 elicits some negative effects on laying performance of Hy-Line brown laying hens.

Photoprotective Effect of Carpomitra costata Extract against Ultraviolet B-Induced Oxidative Damage in Human Keratinocytes

Natural marine products show various biological properties such as antiphotoaging, antioxidant, anticancer, and anti-inflammation. This study evaluated the protective effects of the brown alga Carpomitra costata (Stackhouse) Batters (Sporochnaceae) against ultraviolet B (UVB)-provoked damage in human HaCaT keratinocytes. C. costata extract (CCE) effectively reduced superoxide anion, hydroxyl radical, and UVB-stimulated intracellular reactive oxygen species (ROS) levels. CCE also restored the expression and activity of UVB-suppressed antioxidant enzymes. Furthermore, CCE decreased UVB-triggered oxidative damage to cellular components including DNA, protein, and lipid and defended the cells against mitochondrial membrane depolarization-medicated apoptosis. The results of this study indicate that CCE can safeguard human keratinocytes against UVB-induced cellular damage via a potent antioxidant mechanism. CCE may find utility as part of a therapeutic arsenal against the damaging effects of UVB radiation on the skin.

Effect of Dietary Supplementation of Red Ginseng By-product on Laying Performance, Blood Biochemistry, Serum Immunoglobulin and Microbial Population in Laying Hens

This study was carried out to investigate the effect of dietary supplementation of red ginseng by-product (RGB) on the laying performance, blood biochemistry, and microbial population in laying hens. A total of 120 Hy-Line Brown laying hens (75 weeks old) were randomly allotted to 1 of 3 dietary treatments with 4 replicates per treatment. A commercial-type basal diet was prepared, and 2 additional diets were prepared by supplementing 5.0 or 10.0 g/kg of RGB to the basal diet at the expense of corn. The diets were fed to hens on an ad libitum basis for 4 weeks. There were no differences in feed intake, egg weight, and feed conversion ratio during 4 weeks of the feeding trial. However, hen-day egg production was significantly greater (p<0.05) for the RGB treatment groups than that for the basal treatment group. There were no differences in triglyceride, aspartate aminotransferase, and alanine aminotransferase during the 4-week feeding trial. However, RGB supplementation increased (p<0.05) the serum immunoglobulin G (IgG) and IgM content compared with basal treatment group. The total cholesterol was lower (p<0.05) in the RGB treatments groups than that in the basal treatment group. The intestinal Lactobacillus population was greater (p<0.05) for the RGB treatments groups than that for the basal treatment group. However, the numbers of Salmonella and Escherichia coli were not different among dietary treatments. During the entire experiment, there was no significant difference in egg quality among all the treatments. In conclusion, in addition to improving hen-day production, there were positive effects of dietary RGB supplementation on serum immunoglobulin and cholesterol levels in laying hens.

Negative Susceptibility Vessel Sign and Underlying Intracranial Atherosclerotic Stenosis in Acute Middle Cerebral Artery Occlusion

BACKGROUND AND PURPOSE

The role of MR imaging in predicting underlying intracranial atherosclerotic stenosis before endovascular stroke therapy has not been studied. Our aim was to determine the diagnostic value of the negative susceptibility vessel sign on T2*-weighted gradient-echo MR imaging for predicting underlying intracranial atherosclerotic stenosis in patients with acute MCA occlusion.

MATERIALS AND METHODS

Ninety-one consecutive patients with acute stroke because of MCA occlusion underwent gradient-echo MR imaging and MRA before endovascular therapy. The negative susceptibility vessel sign was defined as an absence of a hypointense signal change within the occluded MCA on gradient-echo imaging. Underlying intracranial atherosclerotic stenosis was determined by conventional angiography. The sensitivity, specificity, predictive values, and accuracy of the negative susceptibility vessel sign for predicting the presence of underlying intracranial atherosclerotic stenosis were assessed.

RESULTS

The negative susceptibility vessel sign was identified in 42 (46.1%) of 91 patients, and 18 (19.8%) patients had an underlying intracranial atherosclerotic stenosis responsible for acute ischemic symptoms. The negative susceptibility vessel sign was more frequently observed in patients with intracranial atherosclerotic stenosis than in those without it (100% versus 32.9%, P < .001). In the prediction of an underlying intracranial atherosclerotic stenosis, the negative susceptibility vessel sign had 100% sensitivity, 67.1% specificity, 42.9% positive predictive value, 100% negative predictive value, and an accuracy of 73.6%.

CONCLUSIONS

The negative susceptibility vessel sign on gradient-echo MR imaging is a sensitive marker with a high negative predictive value for the presence of an underlying intracranial atherosclerotic stenosis in patients with acute ischemic stroke because of MCA occlusions. The susceptibility vessel sign can be used in decision-making when performing subsequent endovascular revascularization therapy in patients with acute MCA occlusions.

Acute basilar artery occlusion: outcome of mechanical thrombectomy with Solitaire stent within 8 hours of stroke onset

BACKGROUND AND PURPOSE

Mechanical thrombectomy with a stent retriever applied shortly after symptom onset could increase good functional outcomes and improve survival in patients with acute basilar artery occlusion, but this has not yet been studied. This study evaluated the efficacy and safety of mechanical thrombectomy with a Solitaire stent within 8 hours of stroke onset in patients with acute basilar artery occlusion.

MATERIALS AND METHODS

We analyzed 25 consecutive patients with acute basilar artery occlusion who were treated with mechanical thrombectomy by use of the Solitaire stent within 8 hours of stroke symptom onset. Successful recanalization was defined as TICI grade 2b or 3. Good outcome was defined as mRS score of 0-2 at 3 months. Clinical and radiologic data in patients with good outcomes were compared with those with poor outcomes.

RESULTS

Successful recanalization was achieved in 96% (24/25) of patients, and 48% (12/25) of patients had good outcomes. Eighty-eight percent (22/25) of patients survived to 3 months. The median NIHSS score on admission was significantly lower in patients with good outcomes than in those with poor outcomes (9.5 versus 14, P = .005). Procedure-related complications occurred in 2 patients (8%). No symptomatic intracerebral hemorrhages occurred.

CONCLUSIONS

The current study suggests that mechanical thrombectomy by use of a Solitaire stent within 8 hours of stroke onset increases good outcomes and improves survival in patients with acute basilar artery occlusion.

Growth performance and hematological traits of broiler chickens reared under assorted monochromatic light sources

A study was conducted to investigate the effect of different monochromatic lights on growth performance and hematological response of growing broiler chickens. A total of 360 one-day-old broiler chicks were randomly divided into 6 lighting treatments, which were replicated 6 times with 10 chicks in each replicate. Six light treatments include incandescent bulbs (as a control) and light-emitting diode white light, blue light, red light, green light, and yellow light (YL). The birds were provided with similar nutritional specifications and environmental management facilities, except for the lights throughout the experimental period. Growth performance was evaluated in terms of BW, BW gain, feed intake, and feed conversion ratio at weekly intervals. At the end of 5 wk, 2 birds from each replicate were randomly selected for blood collection to determine hematological response. The BW and feed intake was numerically higher in YL at 5 wk of age. But interestingly, this did not result in improved feed conversion ratio in YL; nevertheless, numerical values were lower in YL at 5 wk (P > 0.05). Red blood cells, blood platelet count, and percent hematocrit were numerically higher under YL, whereas white blood cell counts and percent hemoglobin remained unaffected due to light treatments. It was concluded that monochromatic light is a potential light source that might provide a beneficial effect on growth performance but is inconclusive for hematological measures of broilers.

Safety of protected carotid artery stenting in patients with severe carotid artery stenosis and carotid intraplaque hemorrhage

BACKGROUND AND PURPOSE

Carotid IPH can be detected with MR imaging. The aim of this study was to determine the safety of CAS using an emboli protection device in patients with severe carotid artery stenosis and MR imaging-depicted carotid IPH.

MATERIALS AND METHODS

We retrospectively reviewed a prospective data base that included 91 consecutive patients with severe carotid stenosis and high-risk features who were treated with CAS by using an emboli protection device. Seventy-eight of the included patients underwent prestenting 3D TOF MRA. IPH was defined as the presence of high signal intensity within the carotid plaque, greater than 150% of the signal intensity of the adjacent neck muscle on TOF source images. The primary outcome measure was the combined incidence of stroke, MI, and death within 30 days of CAS. Associations between IPH and the primary outcome were investigated.

RESULTS

IPH was detected on TOF MRA in 30 patients. Symptomatic patients were more common in the IPH group than in the non-IPH group (66.7% vs 41.7%; P = .032). Overall, 30-day stroke, MI, or death rates were 6.6%. There was no significant difference in the primary outcome between the IPH and non-IPH groups (10% and 6.25%, respectively; hazard ratio for IPH, 1.151; 95% CI, 0.035 to 37.500; P = .937). A logistic regression showed there was no independent variable associated with the primary outcome.

CONCLUSIONS

The results of this study indicate that protected CAS seems to be safe in patients with severe carotid stenosis and IPH.

Sensitivity enhancement in grating coupled surface plasmon resonance by azimuthal control

We present a method for improving the sensing capability of grating coupled surface plasmon resonance (GCSPR) sensors. The grating is rotated azimuthally (phi) until the excitation of double surface plasmon polaritions (SPPs) by a single wavelength is possible. Close to this condition, further tuning of the incident wavelength will merge the double SPPs into a multi-SPP resonance which is angularly broad but spectrally sharp. This is the condition where the momentum vector of the propagating SPP is perpendicular to the incident light momentum. We demonstrate this sensitivity enhancement on a Au grating surface using a dodecanethiol (C12) self-assembled monolayer (SAM). Using this method, a shift in resonance angle as large as 3 degrees can be observed. The simulated sensitivity of this method shows that a sensitivity up to 800 degrees /RIU is achievable, which is one order of magnitude greater than that in a conventional fixed grating (phi = 0 degrees ) as well as the prism-coupled Kretschmann configuration.

Utilization of house fly-maggots, a feed supplement in the production of broiler chickens

Recent studies have suggested the utilization of maggots as a feed supplement forenhanced broiler performance. Maggots, which are a major dietary source of protein, appear during the biodegradation of chicken droppings using house flies. The objective ofthe present study was to investigate the effect of maggot supplementation on the meat quality and growth performance of broiler chickens. A total of 600 one-day-old male commercial broiler chicks (Ross) were randomly assigned into 5 treatment groups consisting of 40 replicates of 3 birds. The birds were fed either a basal diet or the basal diet supplemented with 5.0, 10.0, 15.0 and 20.0% maggots. Overall, broiler chicken performance was influenced by the optimal amino acid profile; high protein (63.99%) and essential amino acid content (29.46%), or high protein digestibility (98.50%) of the maggots. Maggot supplementation caused linear increases in live weight gain but not the feed conversion ratio. The diets of 10 and 15% maggots was the most efficient in terms of average weight gain forthe 4-5 week old broiler chickens (p<0.05). It also significantly increased dressing percentage, breast muscle, and thigh muscle (p<0.05). No differences were observed forliver abdominalfat, or meat color, and the crude protein contents of breast muscle were constant. However, in the maggot-fed broilers, breast muscle lysine and tryptophan levels increased significantly as compared to the birds fed the basal diet (p<0.05). These results indicate that feeding diets containing 10 to 15% maggots in chicken dropping after biodegradation can improve the carcass quality and growth performance of broiler chickens.

Heat stress-induced modulation of host defense against Toxoplasma gondii infection in mice

This study examined the effects of burn injury on murine immune response against Toxoplasma gondii infection. Male C57BL/6 mice were divided into 3 groups: T. gondii infection (group T), burn injury (group B), and burn injury followed by T. gondii infection (group BT). The survival of group BT was significantly lower than those of group B and group T. Parasite abundance in the tissues was determined by quantitative competitive-polymerase chain reaction. Group BT exhibited significantly higher numbers of T. gondii than group T. Antibody production against T.g.HSP30 in group BT was significantly lower than that in group T, whereas no significant difference was observed in SAG1-specific antibody production. Delayed-type hypersensitivity (DTH) specific for 2,4-dinitrofluorobenzene (DNFB) of both group B and group BT was significantly lower than that of group T. One week after infection, serum interferon-gamma (IFN-gamma) and interleukin (IL)-10 levels in group BT were significantly lower, whereas serum IL-6 levels were significantly higher than in group T Serum TNF-alpha levels in both group T and group BT were elevated at 1 wk after infection, although there was no significant difference between them. Serum IFN-gamma, IL-10, and TNF-alpha levels in group B were not elevated during the experimental term. In conclusion, the impaired antigen-specific antibody production and DTH response, together with the modulated patterns of cytokine responses, seemed to be strongly involved in the development of burn-induced immunosuppression and the consequent increased susceptibility to T. gondii infection in mice.

Clinical and laboratory assessment of distal peripheral nerves in Gulf War veterans and spouses

BACKGROUND

The prevalence of symptoms suggesting distal symmetric polyneuropathy (DSP) was reported to be higher among deployed veterans (DV) to the Persian Gulf in 1990-1991 than to control non-deployed veterans (NDV). The authors therefore compared the prevalence of DSP by direct examination of DV and their spouses to control NDV and spouses.

METHODS

The authors performed standardized neurologic examinations on 1,061 DV and 1,128 NDV selected from a cohort of veterans who previously participated in a national mail and telephone survey. Presence of DSP was evaluated by history, physical examination, and standardized electrophysiologic assessment of motor and sensory nerves. Similar examinations were performed without electrophysiologic tests in 484 DV spouses and 533 NDV spouses. Statistical analyses were performed with appropriate adjustments for the stratified sampling scheme.

RESULTS

No differences between adjusted population prevalence of DSP in DV and NDV were found by electrophysiology (3.7% vs 6.3%, p = 0.07), by neurologic examination (3.1% vs 2.6%, p = 0.60), or by the methods combined (6.3% vs 7.3%, p = 0.47). Excluding veterans with non-military service related diseases that may cause DSP did not alter outcomes. DV potentially exposed to neurotoxins from the Khamisiyah ammunition depot explosion did not significantly differ in DSP prevalence compared to non-exposed DV. The prevalence of DSP in DV spouses did not differ from NDV spouses (2.7% vs 3.2%, p = 0.64).

CONCLUSIONS

Neither veterans deployed during the Gulf War era nor their spouses had a higher prevalence of DSP compared to NDV and spouses.

Mortality among US and UK veterans of the Persian Gulf War: a review

Mortality data on Gulf War veterans was reviewed as a means of evaluating the long term consequences of the war. Studies were located from searches of Medline, Proceedings of the Conference on Federally Sponsored Gulf War Veterans' Illnesses Research, Proceedings of the American Public Health Association Annual Meetings, Annual Reports to Congress, and personal contacts with knowledgeable investigators. Data on study design, methods, and results were obtained from published studies of both US and UK veterans who served in the Persian Gulf. The methodology and results of studies are summarised and evaluated. Additional research recommendations based on reviewed studies are presented. It is concluded that in both US and UK studies, mortality from external causes was higher, while mortality from all illnesses was lower among Gulf War veterans in comparison to those of non-Gulf War veterans. Increased mortality from external causes is consistent with patterns of postwar mortality observed in veterans of previous wars. Further follow up of Gulf War veterans and their controls is warranted for evaluating the mortality risk from diseases with longer latency periods.

Clinical characteristics of retinal venous occlusions occurring at different sites

AIMS

To identify the contributory factors associated with different sites of occlusion and the presence or absence of optic nerve head swelling (ONHS).

METHODS

874 cases of retinal venous occlusion (RVO) were prospectively examined at a tertiary referral centre and classified according to three defined sites of occlusion: arteriovenous crossing RVO (AV-RVO); optic cup RVO (OC-RVO); and optic nerve sited RVO. Optic nerve sited RVOs were further divided on the basis of presence (ONHS-RVO) and absence (NONHS-RVO) of ONHS. RVOs not occurring at any of the defined sites were grouped as no-site RVO (NS-RVO). Important clinical parameters were compared among four of the five subgroups by multivariate analysis of variance and chi(2) test (NS-RVO excluded).

RESULTS

The overall multivariate analysis of variance for differences in the mean age, systolic and diastolic blood pressure, body mass index, and intraocular pressure (IOP) among the four subgroups were highly significant (p <0.0001). The F ratios indicated that the differences in the mean age and IOP accounted for this statistical trend. The mean age was statistically significantly lower in the ONHS-RVO group compared to the rest of the groups (p <0.0001). The mean age was significantly higher in OC-RVO compared to the AV-RVO group (p <0.05). The mean IOP was significantly higher in OC-RVO than in the rest of the groups (p <0.01 to 0.0001), while it was also higher in the NONHS-RVO group compared to the ONHS-RVO and AV-RVO groups (p <0.0001). The prevalence of primary open angle glaucoma (POAG), sex, laterality, involvement of the fellow eye, smoking and hypertension were compared by chi(2) tests. POAG was significantly more prevalent in the OC-RVO group than in the rest of the groups (p <0.0083), while it was also significantly more prevalent in the NONHS-RVO group compared to AV-RVO or ONHS-RVO (p <0.0083) groups. Smoking was significantly more prevalent in AV-RVO than in the rest of the groups (p <0.05). The proportion of male sex was significantly higher in ONHS-RVO compared to the AV-RVO group (p <0.05). Hypertension was significantly more prevalent in the AV-RVO than in the ONHS-RVO or NONHS-RVO groups (p <0.05).

CONCLUSION

A new classification of RVO based on the site of occlusion and ONHS has been evaluated. The higher prevalence of hypertension and smoking in AV-RVO suggests a particular importance of cardiovascular risk factors in this group. The association of POAG with CRVO has been confirmed, but only for those cases without ONHS. A distinctive relation between raised IOP and OC-RVO has been demonstrated, suggesting a causal association. RVOs with ONHS tend to occur in younger people, with a higher proportion of males, and a lower prevalence of hypertension and POAG, suggesting that other causal factors may be important in this group. The new scheme resolves the confusion in the literature regarding classification of RVO, and has diagnostic, causal, prognostic, and therapeutic implications.

Per-rectal contrast material for abdominal CT: usefulness of administration with an automatic injector

Adequate distention of the gastrointestinal tract is essential for the best quality image in abdominal computed tomography. We introduce a new technique for per-rectal administration of contrast material with the use of an automatic injector. With this technique, more contrast material can be inserted and thus adequately distend the colon, including the proximal colon.

Urinary N-acetyl-beta-D-glucosaminidase and malondialdehyde as a markers of renal damage in burned patients

This study was aimed to evaluate renal dysfunction during three weeks after the burn injuries in 12 patients admitted to the Hallym University Hankang Medical Center with flame burn injuries (total body surface area, 20-40%). Parameters assessed included 24-hr urine volume, blood urea nitrogen, serum creatinine, creatinine clearance, total urinary protein, urinary microalbumin, 24-hr urinary N-acetyl-beta-D-glucosaminidase (NAG) activity, and urinary malondialdehyde (MDA). Statistical analysis was performed using repeated measures ANOVA test. The 24-hr urine volume, creatinine clearance, and urinary protein significantly increased on day 3 post-burn and fell thereafter. The urine microalbumin excretion showed two peak levels on day 0 post-burn and day 3. The 24-hr urinary NAG activity significantly increased to its maximal level on day 7 post-burn and gradually fell thereafter. The urinary MDA progressively increased during 3 weeks after the burn injury. Despite recovery of general renal function through an intensive care of burn injury, renal tubular damage and lipid peroxidation of the renal tissue suggested to persist during three weeks after the burn. Therefore, a close monitoring and intensive management of renal dysfunction is necessary to prevent burn-induced acute renal failure as well as to lower mortality in patients with major burns.

Mortality among US veterans of the Persian Gulf War: 7-year follow-up

To assess the long-term health consequences of the 1991 Persian Gulf War, the authors compared cause-specific mortality rates of 621,902 Gulf War veterans with those of 746,248 non-Gulf veterans, by gender, with adjustment for age, race, marital status, branch of service, and type of unit. Vital status follow-up began with the date of exit from the Persian Gulf theater (Gulf veterans) or May 1, 1991 (control veterans). Follow-up for both groups ended on the date of death or December 31, 1997, whichever came first. Cox proportional hazards models were used for the multivariate analysis. For Gulf veterans, mortality risk was also assessed relative to the likelihood of exposure to nerve gas at Khamisiyah, Iraq. Among Gulf veterans, the significant excess of deaths due to motor vehicle accidents that was observed during the earlier postwar years had decreased steadily to levels found in non-Gulf veterans. The risk of death from natural causes remained lower among Gulf veterans compared with non-Gulf veterans. This was mainly accounted for by the relatively higher number of deaths related to human immunodeficiency virus infection among non-Gulf veterans. There was no statistically significant difference in cause-specific mortality among Gulf veterans relative to potential nerve gas exposure. The risk of death for both Gulf veterans and non-Gulf veterans stayed less than half of that expected in their civilian counterparts. The authors conclude that the excess risk of mortality from motor vehicle accidents that was associated with Gulf War service has dissipated after 7 years of follow-up.

Hepatocellular carcinoma after systemic chemotherapy: gadolinium-enhanced mr measurement of necrosis by volume histogram

As a preliminary study, we measured the necrosis of advanced hepatocellular carcinoma (HCC) by volume histogram after systemic chemotherapy and correlated it with clinical data. Five patients with advanced HCC secondary to chronic hepatitis and cirrhosis underwent pretreatment and posttreatment MR examination on a 1.5 T MR scanner following systemic chemotherapy. MR sequences included dynamic enhanced fast spoiled gradient echo 3D images. Clinical response to chemotherapy, as determined by MR images, was measured as changes of both the total tumor volume and the percent of tumor necrosis by volume histogram algorithm. Four of five patients had clinical improvement. Three of these patients had no or minimal change of tumor volume; however, there was an increase in tumor necrosis in follow-up MR image. One patient of five with no change in tumor necrosis had no response and died at 3 months. Serial MR images showed increased irregular necrosis of advanced HCC after systemic chemotherapy, but stable volume, in patients who responded clinically to systemic chemotherapy.

Blood-oxygenation-level-dependent functional magnetic resonance imaging for evaluating cerebral regions of female sexual arousal response

OBJECTIVES

To evaluate, for the first time, the cerebral regions associated with female sexual arousal evoked by visual stimulation using noninvasive blood-oxygenation-level-dependent (BOLD) functional magnetic resonance imaging (fMRI).

METHODS

A total of 6 healthy right-handed female volunteers (mean age 33 years, range 25 to 41) underwent fMRI on a 1.5-T MR scanner, in which the BOLD technique was used to create fMR images reflecting local brain activities. Real-time visual stimulation was performed with alternatively combined erotic and nonerotic films to identify the activated brain regions associated with sexual response. The perceived sexual arousal response was assessed using a scale ranging from 1 (no change) to 5 (maximal increase).

RESULTS

The mean score for perceived sexual arousal by erotic visual stimulation was 2.7 on the 5-point scale and was unchanged by nonerotic stimulation. During the visual task, the occipital cortex was activated by both the erotic and the nonerotic films; however, the following cerebral areas were significantly (P <0.05) activated, varying from 4 of 6 to 6 of 6 women: inferior frontal lobe, cingulate gyrus, insula gyrus, corpus callosum, thalamus, caudate nucleus, globus pallidus, and inferior temporal lobe.

CONCLUSIONS

This study is the first to evaluate noninvasive BOLD-fMRI in identifying cerebral regions associated with sexual arousal response evoked by visual stimulation in women.

US Army Chemical Corps Vietnam veterans health study: preliminary results

The long-term health consequences of exposure to phenoxyherbicides used in Vietnam has been a great concern to the veterans. In addition to the Air Force Ranch Hand personnel, Army Chemical Corps personnel who served in Vietnam are thought to have had some of the highest herbicide exposures. The Department of Veterans Affairs commenced a study of veterans who served in Vietnam as members of the Army Chemical Corps and a comparison cohort of Army Chemical Corps personnel who served elsewhere. A total of 2872 Vietnam veterans and 2737 non-Vietnam veterans who served in the Army Chemical Corps were identified for inclusion in a telephone health interview survey with a random 20% sample of veterans receiving serum dioxin and other congeners assessments. In a feasibility study which included 284 Vietnam veterans and 281 non-Vietnam veterans, 100 serum assessments were conducted of which 95 were included in the analysis. Vietnam veterans with a history of spraying herbicides were found to have a statistically significant elevation in their current serum 2,3,7,8-TCDD concentrations compared to non-Vietnam veterans without a spray history (P = 0.05). Other 2,3,7,8-substituted dioxins levels were comparable to the levels found in the non-Vietnam veterans. This feasibility study demonstrated that serum dioxin concentrations from a sample of the study participants can be used to identify exposure variables in the health survey that can serve as a surrogate measure of phenoxyherbicide exposure.

A new potential of blood oxygenation level dependent (BOLD) functional MRI for evaluating cerebral centers of penile erection

It is well known that penile erection is dependent on commands from the central nervous system. However, there has been little research on the central control of penile erection. The aim of this study was to evaluate, for the first time, the cerebral centers of penile erection using BOLD-functional MRI. Functional magnetic resonance imaging (fMRI) on a 1.5T MR scanner was performed in 12 sexually potent male volunteers (mean age: 23) and two hypogonadal impotent patients. In this study, blood oxygenation level dependent (BOLD) technique was utilized to create fMRI reflecting local brain activities. Real-time visual stimulation was performed with an alternatively combined erotic and non-erotic film to identify and quantify the activated brain regions associated with sexual response. Subjective sexual arousal and penile erection responses were assessed using 5-point scales ranging from 1 (no change) to 5 (maximal increase). In normal volunteers, the mean scores on subjective sexual arousal and penile erection by sexual stimulation with erotic film were 3.0 and 3.3 respectively, whereas there were no changes by non-erotic stimulation. During the visual stimulation the occipital cortex was activated by either an erotic or non-erotic film, the erotic film gave 150-200% stronger activation. However, more than seven of the 12 healthy subjects were significantly activated in the areas of inferior frontal lobe, cingulate gyrus, insula gyrus, corpus callosum, thalamus, caudate nucleus, globus pallidus, and inferior temporal lobe by erotic stimulation. In the hypogonadal patients, brain activation in response to the erotic film decreased compared to normal volunteers, however, it was restored by testosterone supplementation. These results are the first demonstration to show the functional neuroanatomy of the brain associated with sexual arousal by visual sexual stimulation using BOLD-based fMRI. Further studies are needed to verify that fMRI provides an important new tool in evaluating the cerebral center of the penile erection.

Pathogenesis of virus-induced immune-mediated demyelination

Theiler's murine encephalomyelitis virus-induced demyelinating disease has been extensively studied as an attractive infectious model for human multiple sclerosis. Virus-specific inflammatory Th1 cell responses followed by autoimmune responses to myelin antigens play a crucial role in the pathogenic processes leading to demyelination. Antibody and cytotoxic T cells (CTL) responses to virus appears to be primarily protective from demyelinating disease. Although the role of Th1 and CTL responses in the induction of demyelinating disease is controversial, assessment of cytokines produced locally in the central nervous system (CNS) during the course of disease and the effects of altered inflammatory cytokine levels strongly support the importance of Th1 responses in this virus-induced demyelinating disease. Induction of various chemokines and cytokines in different glial and antigen presenting cells upon viral infection appears to be an important initiation mechanism for inflammatory Th1 responses in the CNS. Coupled with the initial inflammatory responses, viral persistence in the CNS may be a critical factor for sustaining inflammatory responses and consequent immune-mediated demyelinating disease.

Inhibition of cell growth and telomerase activity of breast cancer cells in vitro by retinoic acids

The effects of retinoic acid (RA) and its analogs, all-trans RA, 9-cis RA and 13-cis RA, were investigated in human breast cancer MCF-7 cells and immortalized breast epithelial cell line MCF-10A. RA inhibited the telomerase activity of MCF-7 cells in a wide range of concentrations. RA at 10 microM also inhibited the growth of MCF-7 cells in a time-dependent manner. However, no significant growth inhibition was found between untreated control and RA-treated MCF-10A cells. Moreover, a marked inhibition of telomerase activity by RA was detected early in MCF-7 cells (after 24 h of RA treatment), which was preceded by a reduction of hTERT mRNA expression (after 12 h of RA treatment). However, MCF-10A cells showed a reduction of telomerase activity and down-regulation of hTERT after 4 days of RA treatment. Simultaneous changes in hTERT mRNA expression and telomerase activity were found for MCF-10A cells. The expressions of hTR and hTEP1 telomerase component genes were not changed after RA treatment. These results indicate that the anti-breast cancer activity of RA could be mediated by its ability to down-regulate the expression of hTERT telomerase gene.

Prevalence of gynecologic cancers among female Vietnam veterans

The possibility of a gender-specific health problem associated with the Vietnam War has been a concern since the war. We targeted 4140 female Vietnam veterans and 4140 veteran controls to complete a structured telephone interview that included questions regarding any history of gynecologic cancer. As a measure of association between the risk of cancer and military service in Vietnam, odds ratios and 95% confidence intervals were calculated using multiple logistic regression models that yielded estimates of potential cofounders. Although 8% of Vietnam veterans and 7.1% of non-Vietnam veterans reported a history of gynecologic cancers, namely, breast, ovary, uterus, or cervix, the difference was not statistically significant either for the individual site or for the gynecologic cancers as a group. Female Vietnam veterans have not experienced a higher prevalence of gynecologic cancer in the 30 years since the conflict.

Heterotopic pancreas in the stomach: CT findings

PURPOSE

To describe the computed tomographic (CT) findings of heterotopic pancreas in the stomach.

MATERIALS AND METHODS

CT findings in 12 patients with heterotopic pancreas in the stomach were reviewed. Surgical resection (n = 11) or endoscopic excision (n = 1) was performed in cases of symptomatic heterotopic pancreas (n = 4), suspected submucosal tumors (n = 7), and gastric carcinoma (n = 1). Seven patients underwent helical CT with water as an oral contrast agent; five underwent nonhelical CT with water-soluble contrast material.

RESULTS

Nine heterotopic pancreata were in the antrum and one each was in the body, fundus, and perigastric fat. Seven lesions were on the greater curvature aspect; five, on the lesser curvature aspect. Common CT findings were well-defined oval or round masses with smooth or serrated margins in the gastric antral wall. Four of the seven lesions in which helical CT was performed enhanced similarly to normal pancreas. Preoperatively, CT depicted 11 of the 12 lesions, but CT findings were interpreted correctly as heterotopic pancreas in only two; the remaining 10 were misinterpreted as other lesions. Atypical findings were cystic dilatation of heterotopic pancreatic duct in two, unusual location in the fundus or perigastric fat in two, and malignant transformation in one.

CONCLUSION

CT findings of heterotopic pancreas in the stomach appear to be nonspecific for diagnosis, except for location.

A mortality follow-up study of WW II submariners who received nasopharyngeal radium irradiation treatment

BACKGROUND

During World War II, large numbers of submarine trainees received nasopharyngeal radium irradiation therapy to treat aerotitis media or middle ear barotrauma.

METHODS

Using a life table and the Cox proportional hazards model, mortality risk of 1, 214 submariners believed to have received treatment for aerotitis media was compared to 3,176 "untreated" submariners.

RESULTS

"Treated" submariners had a significant increased mortality risk for all causes (odds ratio (OR) = 1.32; 95% confidence interval (CI) = 1. 14-1.53) and circulatory diseases (OR = 1.51; 95% CI = 1.20-1.90), and a non-significant increased mortality risk of head and neck cancer (OR = 1.40; 95% CI = 0.54-3.58).

CONCLUSIONS

While the excess risk was not statistically significant by conventional standards, the finding does suggest that those who received NP radium irradiation therapy may be at increased risk of death due to head and neck cancers. Due to the lack of data the role of risk factors other than radium exposure cannot be assessed.

Pregnancy outcomes among U.S. women Vietnam veterans

BACKGROUND

Since the 1965-1975 Vietnam War, there has been persistent concern that women who served in the U.S. military in Vietnam may have experienced adverse pregnancy outcomes.

METHODS

We compared self-reported pregnancy outcomes for 4,140 women Vietnam veterans with those of 4,140 contemporary women veterans who were not deployed to Vietnam. As a measure of association, we calculated odds ratios (OR) and 95% confidence intervals (CI) using logistic regression adjusting for age at conception, race, education, military nursing status, smoking, drinking and other exposures during pregnancy.

RESULTS

There was no statistically significant association between military service in Vietnam and index pregnancies resulting in miscarriage or stillbirth, low birth weight, pre-term delivery, or infant death. The risk of having children with "moderate-to-severe" birth defects was significantly elevated among Vietnam veterans (adjusted OR = 1.46, 95% CI = 1.06-2.02).

CONCLUSIONS

The risk of birth defects among index children was significantly associated with mother's military service in Vietnam.

Pattern of vascular nonperfusion in retinal venous occlusions occurring within the optic nerve with and without optic nerve head swelling

OBJECTIVE

To investigate the significance of optic nerve head swelling (ONHS) in relation to the pattern of vascular nonperfusion, visual acuity (VA), and demographic profile in retinal venous occlusions (RVOs) occurring within the optic nerve.

METHODS

Cases of RVO occurring within the optic nerve were divided on the basis of the presence (105 cases) or absence (163 cases) of ONHS. This division was performed by examining the color stereo fundus photographs in conditions masked from other clinical parameters. Duration of symptoms before assessment, age, and sex distributions were compared. The vein involved was identified, and the occlusion was confirmed to have occurred within the optic nerve by observing that the vein pierced the lamina cribrosa as a dilated vein. Fluorescein angiographs were examined, and the extent of vascular nonperfusion in the macula and peripheral retina was quantified from grade 1 to grade 4. The extent of break in the perifoveal capillary arcade was graded as 0, less than or equal to 90 degrees, and greater than 90 degrees. Best-corrected VA was assessed using the Snellen chart.

RESULTS

The 2 groups were comparable in terms of the duration of the symptoms before examination. The mean age was significantly younger in the group with ONHS (58.3 vs 65.1 years, P<. 001). Age distribution by sex demonstrated a higher proportion of men younger than 50 years in the ONHS group (19.1% vs 8.6%, P =.01). The group without ONHS involved the papillary vein more frequently (31.3% vs 17.1%, P =.01). The respective proportions of grade 1, 2, 3, and 4 vascular nonperfusion in the macula were 90.5%, 9.5%, 0%, and 0% in the ONHS group, and 62.6%, 14.7%, 13.5%, and 9.2% in the group without ONHS (P<.001). The corresponding proportions for the peripheral retina were 90.4%, 8.7%, 0%, and 1.0% in the ONHS group, and 62.7%, 13.0%, 18.0%, and 6.2% in the group without ONHS (P<.001). In 64.6% of cases with ONHS and 42.9% of cases without, the perifoveal arcade was intact. A break greater than 90 degrees in the perifoveal arcade was present in 12.5% of cases with and 23.6% of cases without ONHS (P =.004). The median VA was significantly better in the ONHS group (6/24 vs 6/48, P =.005).

CONCLUSIONS

The RVOs occurring within the optic nerve can be subdivided into 2 distinct groups on the basis of ONHS. The presence of ONHS is associated with younger age, less severe vascular nonperfusion, and better VA. This is consistent with a retrocribrosal site of occlusion, which has access to the pial plexus that can provide collateral channels for retinal venous drainage.

Imaging evaluation of ovarian masses

Adnexal masses present a special diagnostic challenge, in part because benign adnexal masses greatly outnumber malignant ones. Determination of a degree of suspicion for malignancy is critical and is based largely on imaging appearance. Endovaginal ultrasonography (US) is the most practical modality for assessment of ovarian tumors because it is readily available and has a high negative predictive value. Morphologic analysis of adnexal masses is accurate for identifying masses as either low risk or high risk. The most important morphologic features are non-fatty solid (vascularized) tissue, thick septations, and papillary projections. Color Doppler US helps identify solid, vascularized components in a mass. Spectral Doppler waveform characteristics (eg, resistive index, pulsatility index) correlate well with malignancy but generally add little information to morphologic considerations. Computed tomography can help assess the extent of disease in patients before and after primary cytoreductive surgery. Magnetic resonance (MR) imaging is better reserved for problem solving when US findings are nondiagnostic or equivocal because, although it is more accurate for diagnosis, it is also more expensive. The signal intensity characteristics of ovarian masses make possible a systematic approach to diagnosis. Mature cystic teratomas, cysts, endometriomas, leiomyomas, fibromas, and other lesions can be accurately diagnosed on the basis of T1-weighted, T2-weighted, and fat-saturated T1-weighted MR imaging findings.

The macular hole: report of an Australian surgical series and meta-analysis of the literature

PURPOSE

To report an Australian series of macular hole surgery by pars plana vitrectomy and fluid-gas exchange, and to identify factors influencing the outcome of the surgery through meta-analysis of the literature.

METHODS

Fifty-six consecutive cases of macular hole were treated by pars plana vitrectomy, fluid-gas exchange and face-down positioning for at least 7 days, and prospectively followed for 3-12 months. Thirty-six reports of macular hole surgery were reviewed. A meta-analysis on the pre- and postoperative parameters was performed on 389 cases, in which case-specific data-points were available.

RESULTS

In the current series, anatomical closure was achieved in all (100%) of 16 stage 2, and in 35 (87.5%) of 40 stage 3 or 4 macular holes. At least 2 logMAR lines of improvement in visual acuity were seen in 10 (62.5%) stage 2 and 20 (50.0%) stage 3 or 4 holes. Postoperative visual acuity was 6/12 or better in 10 (62.5%) stage 2 and 17 (42.5%) stage 3 or 4 holes. In both the current series and the meta-analysis, favourable surgical outcomes were associated with stage 2 macular holes, better preoperative visual acuity, and shorter preoperative duration. Adjuvant use was associated with a higher rate of anatomical closure but there was no clear benefit in terms of postoperative visual acuity.

CONCLUSION

Our experience and the results of the meta-analysis suggest that macular hole surgery should be offered as early as possible once full-thickness neuroretinal defect occurs.

Indocyanine green angiographic features of varix of the vortex vein ampulla

Varix of the vortex vein ampulla is a rare, benign, asymptomatic condition, which may be confused with a choroidal naevus or melanoma. A 28-year-old man was referred to a tertiary retinal practice with a diagnosis of choroidal naevus. The lesion was an elevated choroidal mass in the superonasal peripheral retina measuring 2 by 1 disc diameters. It was dark red to burgundy in colour and disappeared under digital pressure applied to the globe. The methods used in diagnosis were colour fundus photography, fluorescein angiography and indocyanine green angiography using a scanning laser ophthalmoscope. On fluorescein angiography the lesion was initially hypofluorescent, becoming isofluorescent 25 s after dye injection. Indocyanine green angiography demonstrated the lesion to be two separate dilatations of the vortex vein ampullae. The dilatations collapsed when pressure was applied to the globe. A choroidal mass that collapses under pressure applied to the globe should suggest a varix of the vortex vein ampulla. Indocyanine green angiography is useful in demonstrating the outline of the varix of the vortex vein ampulla.

Cancer mortality among the highest exposed US atmospheric nuclear test participants

Of the estimated 205,000 military personnel who participated in the US atmospheric nuclear weapons testing program from 1945 to 1962, less than 1% had ionizing radiation doses that met or exceeded the current federal occupational guideline for dose of 5 rem (roentgen equivalents in humans) in a 12-month period. The objective of this study was to determine whether veterans who received the highest gamma radiation doses (n = 1010) have experienced increased cancer mortality compared with a group of Navy veterans who received a minimal radiation dose as participants of HARDTACK I (n = 2870). Mortality from all causes of death (relative risk, 1.22; 95% confidence interval, 1.04 to 1.44) and from all lymphopoietic cancers (relative risk, 3.72; 95% confidence interval, 1.28 to 10.83) was significantly elevated among the 5-rem cohort compared with the Navy controls. The lack of statistically significant excesses in deaths from many of the known radiogenic cancers suggests that the observed excess mortality may be the result of many factors, of which radiation exposure was only one.

Illnesses among United States veterans of the Gulf War: a population-based survey of 30,000 veterans

Despite numerous studies on veterans of the 1990 to 1991 Gulf War, the fundamental questions of how healthy they are and how their health compares with that of their military peers who were not deployed to the Gulf have not been fully answered. We conducted a health survey in which the health outcomes of a population-based sample of 15,000 Gulf veterans representing various military branches and unit components (regular, reserve, National Guard) were compared with those of 15,000 non-Gulf veterans who were randomly sampled to mirror the number in the same military strata in the Gulf veteran group. In comparison with their peers, Gulf veterans had a higher prevalence of functional impairment, health care utilization, symptoms, and medical conditions and a higher rate of low general health perceptions. A longitudinal follow-up of the health of these veterans will be needed to detect changes in health status and to detect diseases with a long latency period.

Two flavonoids from the leaves of Morus alba induce differentiation of the human promyelocytic leukemia (HL-60) cell line

Two flavonoids, quercetin-3-O-beta-D-glucopyranoside (1) and quercetin-3,7-di-O-beta-D-glucopyranoside (2), were isolated from the leaves of Morus alba (Moraceae). These two flavonoids exerted a significant inhibitory effect on the growth of the human promyelocytic leukemia cell line (HL-60) at the concentration of 2 x 10(-4) M. Compound 2 also induced differentiation of the HL-60 cell line to express CD 66b and CD 14 antigens. These flavonoids exhibited significant free radical scavenging effects on 1,1-diphenyl-2-picryl-hydrazyl radical.

Processing and reactivity of T cell epitopes containing two cysteine residues from hen egg-white lysozyme (HEL74-90)

The Ag processing and structural requirements involved in the generation of a major T cell epitope from the hen egg-white lysozyme protein (HEL74-88), containing two cysteine residues at positions 76 and 80, were investigated. Several T cell hybridomas derived from both low responder (I-Ab) and high responder (I-Ak) mice recognize this region. These hybridomas are strongly responsive to native HEL, but unresponsive to the reduced and carboxymethylated protein. Air-oxidized HEL74-88 peptide was unable to bind I-Ak molecules and failed to stimulate T cells in the absence of intracellular Ag processing. Further functional competition assays showed that alkylation of cysteine residues with bulky methyl groups interferes with the contacts for the MHC class II molecules (I-Ak) of high responder mice and the I-Ab-restricted TCR of low responder mice. Serine substitutions of the cysteine residues of HEL74-88 either enhanced or abrogated T cell stimulation by the peptides without significant alterations in the class II binding. These results suggest that the cysteine residues of peptides must be free from disulfide bonding for efficient stimulation of T cells and yet frequently used modifications of cysteine residues may not be suitable for peptide-based vaccine development.

Are Gulf War veterans suffering war-related illnesses? Federal and civilian hospitalizations examined, June 1991 to December 1994

A previous epidemiologic study demonstrated no unexplained increase in risk for postwar hospitalization among Gulf War veterans who had remained on active duty. The authors sought to expand this study to include Reserve and separated military personnel. They examined hospitalization data from the Department of Defense, the Department of Veterans Affairs (VA), and the California Office of Statewide Health Planning and Development hospital systems for the years 1991-1994. Since denominator data were not available, the authors compared the proportional morbidity ratios (PMRs) of hospitalization discharge diagnoses (both large categories and specific diagnoses) between Gulf War veterans and other veterans of the same era. There were no indications that Gulf War veterans were suffering increased PMRs for infectious diseases; neoplasms; endocrine diseases; blood diseases; skin conditions; or diseases of the nervous system, circulatory system, or musculoskeletal system. However, these veterans did experience proportionally more hospitalizations for various specific diagnoses, namely, fractures and bone and soft-tissue injuries (Department of Defense and California Office of Statewide Health Planning and Development), various diseases of the respiratory (including asthma) and digestive systems (VA), and diverse symptom diagnoses (VA). While these findings may be influenced by chance or by a number of potential confounders, including health registry participation, they merit further examination using other study designs.

Thermolabile 8-hydroxyguanine DNA glycosylase with low activity in senescence-accelerated mice due to a single-base mutation

8-hydroxyguanine (8-oxoguanine; oh8Gua) DNA glycosylase (OGG1) repairs oh8Gua, a highly mutagenic oxidative DNA damage. In the present study, we compared two strains of senescence-accelerated mouse (SAM) expressing senescence-prone phenotypes, SAMP1 and SAMP8, with one strain of SAM expressing senescence-resistant phenotype, SAMR1. We found three distinct characteristics of OGG1 in SAMPs: (i) low activity (10-40% of the SAMRI enzyme in all organs and ages observed), (ii) thermolability, and (iii) mutation from Arg (CGG) in SAMR1 to Trp (TGG) at codon 304. There was no difference in the levels of mRNA and protein. As expected, oh8Gua level in tissues was higher in the SAMPs. In contrast, O6-methylguanine-DNA methyltransferase, which repairs alkylated DNA, showed no difference in its activity. The impairment of oh8Gua repair activity caused by the 304 mutation in OGG1 may be one of the factors contributing to the high somatic mutation rate and the accelerated senescence observed in these strains.