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Objective: The primary objective of this study was to determine the effects of temperature on viral erythrocytic necrosis (VEN) progression under controlled conditions. Secondarily, this study was intended to evaluate the combined effects of temperature and VEN on the Pacific Herring Clupea palasii transcriptome., Methods: The effects of temperature on VEN progression were assessed by waterborne exposure of laboratory-reared, specific-pathogen-free Pacific Herring to tissues homogenates containing erythrocytic necrosis virus (ENV) at 6.9, 9.0, or 13.5°C., Result: Exposure of Pacific Herring to ENV resulted in the establishment of infections characterized by high infection prevalence (89%; 40/45) and mean viral loads (5.5 log 10 [gene copies/μg genomic DNA]) in kidney tissues at 44 days postexposure. Mean viral loads were significantly higher in fish from the ambient (mean = 9.0°C) and warm (mean = 13.5°C) treatments (6.1-6.2 log 10 [gene copies/total genomic DNA]) than in fish from the cool (mean = 6.9°C) treatment (4.3 log 10 [gene copies/μg genomic DNA]). Similarly, the peak proportion of diseased fish was directly related to temperature, with cytoplasmic inclusion bodies detected in 21% of fish from the cool treatment, 52% of fish from the ambient treatment, and 60% of fish from the warm treatment. The mean VEN load in each fish (enumerated as the percentage of erythrocytes with cytoplasmic inclusions) at 44 days postexposure increased with temperature from 15% in the cool treatment to 36% in the ambient treatment and 32% in the warm treatment. Transcriptional analysis indicated that the number of differentially expressed genes among ENV-exposed Pacific Herring increased with temperature, time postexposure, and viral load. Correlation network analysis of transcriptomic data showed robust activation of interferon and viral immune responses in the hepatic tissue of infected individuals independent of other experimental variables., Conclusion: Results from this controlled laboratory study, combined with previous observations of natural epizootics in wild populations, support the conclusion that temperature is an important disease cofactor for VEN in Pacific Herring., (Published 2023. This article is a U.S. Government work and is in the public domain in the USA.)

Throughout a 20 year biosurveillance period, viral hemorrhagic septicemia virus was isolated in low titers from only 6/7355 opportunistically sampled adult Pacific herring, reflecting the typical endemic phase of the disease when the virus persists covertly. However, more focused surveillance efforts identified the presence of disease hot spots occurring among juvenile life history stages from certain nearshore habitats. These outbreaks sometimes recurred annually in the same temporal and spatial patterns and were characterized by infection prevalence as high as 96%. Longitudinal sampling indicated that some epizootics were relatively transient, represented by positive samples on a single sampling date, and others were more protracted, with positive samples occurring throughout the first 10 weeks of the juvenile life history phase. These results indicate that viral hemorrhagic septicemia (VHS) epizootics in free-ranging Pacific herring C. pallasii are more common than previously appreciated; however, they are easily overlooked if biosurveillance efforts are not designed around times and locations with high disease potential.

An analysis of daily water samples collected from an index site on Big Soos Creek, Washington indicated intra-annual differences in the concentrations of waterborne Nanophyetus salmincola. Waterborne concentrations, quantified as gene copies/L, peaked during the fall (October-November 2016), decreased to very low concentrations over the winter (January-March 2017), and then increased in the spring and throughout the summer. High waterborne concentrations of N. salmincola DNA (2 × 10 6 gene copies/L) corresponded with live N. salmincola cercariae (mean = 3 cercariae/L) that were detected in companion water samples. Spikes in waterborne N. salmincola concentrations in October and November typically coincided with increases in streamflow; this combination resulted in elevated infection pressures during high water events in the fall. The peak in waterborne N. salmincola concentrations corresponded with an accompanying peak in tissue parasite density (metacercariae/posterior kidney) in Coho Salmon Oncorhynchus kisutch that were reared in the untreated water., (© 2019 American Fisheries Society.)

The ability of formalin, PEROX-AID (hydrogen peroxide), and seawater to kill waterborne Nanophyetus salmincola cercariae was evaluated in vitro. Newly emerged cercariae survived for extended periods in freshwater, with 53-73% survival occurring in negative control groups after 24 h. Exposure to dilutions of formalin reduced this survival time, with 0% of cercariae surviving after 30 min in 450 μL/L, 40 min in 225 μL/L, and 300 min in 113 μL/L. Exposure to PEROX-AID (hydrogen peroxide) for 1 h resulted in reduced cercarial survival (16.4%) only at the highest concentration (100 μL/L), compared with 100% survival in the untreated controls and all lesser concentrations. Exposure to dilutions of seawater resulted in reduced cercarial survival only at high salinities (15.2-30.3‰), where 10-min exposures resulted in 0-20% survival. These results provide insights into options for prophylactic water treatment at salmonid enhancement facilities that experience high mortalities due to infections with Nanophyetus salmincola. Further, the intolerance of live cercariae to high salinities indicates that exposure to fish occurs primarily in the freshwater portions of watersheds., (Published 2018. This article is a U.S. Government work and is in the public domain in the USA.)

The protistan parasite Ichthyophonus sp. occurs in coastal populations of Pacific Herring Clupea pallasii throughout the northeast Pacific region, but the route(s) by which these planktivorous fish become infected is unknown. Several methods for establishing Ichthyophonus infections in laboratory challenges were examined. Infections were most effectively established after intraperitoneal (IP) injections with suspended parasite isolates from culture or after repeated feedings with infected fish tissues. Among groups that were offered the infected tissues, infection prevalence was greater after multiple feedings (65%) than after a single feeding (5%). Additionally, among groups that were exposed to parasite suspensions prepared from culture isolates, infection prevalence was greater after exposure by IP injection (74%) than after exposure via gastric intubation (12%); the flushing of parasite suspensions over the gills did not lead to infections in any of the experimental fish. Although the consumption of infected fish tissues is unlikely to be the primary route of Ichthyophonus sp. transmission in wild populations of Pacific Herring, this route may contribute to abnormally high infection prevalence in areas where juveniles have access to infected offal.

Two hundred rheumatoid arthritis (RA) patients taking low dose methotrexate (MTX) were evaluated for adverse effects. During a mean follow up of 41.5 months, the mean cell volume (MCV) was elevated at some time during the course of treatment in 42 patients. The MCV was normal in the remaining 158 patients. One hundred ninety-eight patients were treated simultaneously with oral folic acid. With the exception of heartburn, which was seen more often in the high MCV group, there was no difference in the frequency of adverse effects attributable to MTX between groups. Severity of side effects and the frequency of MTX dose reduction and MTX discontinuation due to toxicity were also similar between groups. This analysis suggests that elevation of MCV in RA patients treated simultaneously with MTX and folate does not predict MTX toxicity. The authors also discuss the mechanism of action of MTX with regard to folate metabolism.

Purpose: Methotrexate (MTX), when used to treat malignancy or psoriasis, has been implicated in anecdotal reports as a teratogen or abortifacient in the first trimester of pregnancy. We are unaware of any previous reports that describe the course of gestation and the effect on subsequent offspring in patients treated with low-dose oral MTX for rheumatoid arthritis, and therefore present our experience., Patients and Methods: We report on eight women experiencing 10 pregnancies. Mean number of weeks of gestation while taking MTX was 7.5 (range 2 to 20 weeks). Outcome of pregnancies included five full-term babies (FTB), three spontaneous abortions (SAB), and two elective abortions., Results: There were no significant differences in either the FTB or SAB group when considering risk factors including smoking, alcohol, concomitant medications, and age. One of three in the SAB group had recurrent abortions prior to MTX therapy. All five of the FTB group had uncomplicated pregnancies and deliveries. All offspring were of normal height and weight at birth with no physical abnormalities. All children reached growth, development, and intellectual stages normally, and their present mean age is 11.5 years. No observed learning disabilities or medical abnormalities have occurred in any of these children., Conclusion: In this uncontrolled study we failed to demonstrate tertogenicity of MTX. However, the possibility of abortion due to MTX use remains.

Chloroquine and hydroxychloroquine effectively suppress rheumatoid arthritis with a superior benefit to risk ratio. Controlled studies demonstrate moderate efficacy in about 70 percent of patients. High-grade suppression is seen in 15 percent and partial suppression in 55 percent. The dropout rate for poor efficacy is 30 percent and for side effects 3 to 7 percent. Most studies show antimalarials to be almost equivalent to chrysotherapy in potency. Antimalarials are indicated for active rheumatoid arthritis not optimally controlled with nonsteroidal anti-inflammatory drugs and for all cases of progressive disease. Therapy is continued indefinitely. Safe use of these drugs depends on daily dosage. With the single exception of late stage retinopathy, other adverse effects are fully reversible. Strict adherence to three tested safety rules virtually eliminates retinopathy and prevents loss of vision: (1) limit the daily dosage: chloroquine 3.5 to 4.0 mg/kg per day or hydroxychloroquine 6.0 to 6.5 mg/kg per day based on lean body weight; (2) subject the patient to an annual ocular examination to age 65, twice annually thereafter; (3) adjust treatment for pharmacokinetic variables. The lower risk and nearly comparable efficacy make antimalarials first choice among remittive drugs.

The pharmacokinetics, physiologic effects, and the metabolization of chloroquine and hydroxychloroquine are all similar. Their concentrations in plasma and tissue are directly related to daily dosing. The highest concentrations are found in melanin-containing tissues, particularly the choroid and ciliary body of the eye. The pharmacologic effects of 4-aminoquinoline compounds are reviewed in detail. It is likely that the rheumatologic effectiveness of these agents is primarily related to lysosomal actions. The drug-induced lysosomal abnormalities include diminished vesicle fusion, diminished exocytosis, and reversible "lysosomal storage disease." It is likely that the retinal toxicity of these drugs is one manifestation of the altered lysosomal physiology involving the retinal pigmented epithelium. Tissue of retinal pigmented epithelium is similar to that of the bone-marrow-derived macrophage. Depression of extra-oculogram is an early sign of excessive dosage and can be used to measure potential toxicity during therapy with 4-aminoquinolines. Dosages ranging from 3.5 to 4.0 mg/kg per day for chloroquine and 6.0 to 6.5 mg/kg per day for hydroxychloroquine are clinically safe.

We carefully selected 30 men with primary gout, rendered asymptomatic by therapy, to examine the frequency and type of hyperlipidemia and hyperlipoproteinemia, with the objective of determining whether serum uric acid, alcohol intake, liver function, kidney function, and (or) drugs were participating in the secondary lipid disorder. Sixty-one age- and sex-matched men were used as controls. About 73% of the gout patients had hypertriglyceridemia, 1.6-fold the frequency found in the control group. Types IV and IIb lipoprotein electrophoretic patterns were most prevalent in the gout group. Neither alcohol intake nor hyperuricemia, per se, seems to be the cause of the lipid and lipoprotein disorder and cannot be related to liver or kidney dysfunctions. Obesity was the major underlying factor associated with the lipidemia. The study suggests that diet and, possibly, defective clearance of triglycerides may be etiologic factors associated with the abnormal serum triacylglycerol (triglyceride) and lipoprotein concentrations in these individuals.

The differential diagnosis of subacute or chronic polyarthritic diseases, including rheumatoid arthritis, is based on recognizing a pattern of changes, with special emphasis placed on certain key features that possess higher specificity. The clinical history is by far the most important diagnostic tool and involves clear assessment of the distribution of joint involvement, whether pain is articular or extra-articular, whether a syndrome follows trauma or infection, and the duration of the process. The distribution of involved joints is a major contributor to differential diagnosis but can be misleading unless a skilled physical examination confirms objective synovitis. If present, nodules, which represent localization of the disease process, also offer a powerful tool in differential diagnosis. Rheumatoid nodules occur in about 20 percent of patients with well-developed rheumatoid arthritis. The effects of inflammation may be clinically detectable, but laboratory tests--e.g., the erythrocyte sedimentation rate and quantitative C-reactive protein--provide the most reliable evidence of inflammation. Synovial fluid analysis may reveal inflammatory changes and other abnormalities permitting diagnosis. Rheumatoid factor is present in about 80 percent of patients with rheumatoid arthritis but is not specific for this diagnosis.

No eye disease was detected in over 900 rheumatoid arthritis patients treated with less than 4.0 mg/kg per day of chloroquine or less than 6.5 mg/kg per day of hydroxychloroquine for a mean of about seven years. I therefore consider these dosage rates safe, since they are below the threshold of retinal toxicity. This is based on more than 6,000 patient-years of drug exposure. That dosage threshold for retinopathy appears to be 5.1 mg/kg per day for chloroquine and 7.8 mg/kg per day for hydroxychloroquine according to my studies with these compounds. The daily dosage rate, rather than total drug accumulation, seems to determine the development of eye disease. To prevent overdosage, dosing should be calculated not on the actual weight of the patient but on ideal (lean) body weight. Furthermore, the patient's renal and liver function should also be taken into account to avoid overdosage. Since exposure to light amplifies the risk of retinopathy in patients treated with antimalarials, dark sunglasses are recommended for patients spending much time in sunlight.