Epidemiological study to investigate the incidence and prevalence of clinical mastitis, peracute mastitis, metabolic disorders and peripartum disorders, on a dairy farm in a temperate zone in Japan

Background

Our aim was to investigate the incidence and prevalence of clinical mastitis, peracute mastitis, metabolic disorders, and peripartum disorders, and to examine factors affecting the prevalence of each disease in cows raised on a large dairy farm in a temperate climate in Japan. The present study was performed on a large commercial dairy farm with approximately 2500 Holstein cows. Data were collected from 2014 to 2018, and involved 9663 calving records for 4256 cows.

Results

The incidence rate on the farm was 21.9% for clinical mastitis, 10.4% for peracute mastitis, 2.9% for metabolic disorders, and 3.2% for peripartum disorders. The prevalence rates for clinical mastitis, peracute mastitis, metabolic disorders, and peripartum disorders were 28.0, 13.3, 3.7, and 4.0%, respectively. In all four diseases, the probability of time to occurrence for each disease was associated with parity and calving season (P < 0.05). Regarding metabolic disorders and peripartum disorders, the probability of occurrence decreased during the first 10 days after calving.

Conclusions

Our results showed that clinical mastitis occurred most often in this temperate zone, and that metabolic disorders and peripartum disorders occurred from calving to day 10 post-calving.

Assessment of abortion risk of sows on Japanese commercial farms infected with porcine epidemic diarrhea virus

The objectives of this study were to assess abortion risk (AR) and the number of piglets that died during suckling periods per litter (DP) in farms infected with porcine epidemic diarrhea (PED) in relation to herd immunization procedures. Data were obtained from 91 farms in Japan that had PED infection during 2013 to 2014. The 91 PED-positive farms were asked the number of abortions that occurred and DP for 3 months (1 month before PED outbreak (previous month), 1 month after PED outbreak (the month of PED), and from 1 month after PED outbreak to 2 months after PED outbreak (following month)). AR in each month was calculated as the number of abortions divided by sow inventory. Both AR and DP in the month of PED were higher than those in the previous and following months (p < .05). Farms that performed a herd immunization procedure had higher AR and DP in the month of PED than those that did not perform the procedure (p < .05). In summary, PED occurrence increased AR and DP.

Development of a biosecurity assessment tool and the assessment of biosecurity levels by this tool on Japanese commercial swine farms

It is well known that infectious diseases such as porcine reproductive and respiratory syndrome (PRRS) and porcine epidemic diarrhea (PED) decrease herd productivity and lead to economic loss. It is believed that biosecurity practices are effective for the prevention and control of such infectious diseases. Therefore, the objective of the present study was to investigate whether or not an association between biosecurity level and herd productivity, as well as disease status exists on Japanese commercial swine farms. The present study was conducted on 141 farms. Biosecurity in each farm was assessed by a biosecurity assessment tool named BioAsseT. BioAsseT has a full score of 100 and consists of three sections (external biosecurity, internal biosecurity and diagnostic monitoring). Production data for number of pigs weaned per sow per year (PWSY) and post-weaning mortality per year (PWM) were collected for data analysis. Regarding PRRS status, the farms were categorized into two groups: unknown or unstable and stable or negative. In addition, these farms were categorized based on their PED status, either positive or negative. The total BioAsseT score was associated with herd productivity: as total score increased by 1, PWSY increased by 0.104 pigs and PWM decreased by 0.051 % (P <  0.05). Herd productivity was associated with the score of external and internal biosecurity (P <  0.05), but did not correlate with the score of diagnostic monitoring. Regarding PRRS status, farms with an unknown or unstable status had lower total score than those with stable or negative status (P < 0.05). Similarly, PED positive farms had a lower total score compared to PED negative farms (P <  0.05). In conclusion, the present study provides evidence for the association between high biosecurity levels and increased herd productivity as well as a decreased risk for novel introductions of infectious diseases such as PED.

Robotic-assisted multivisceral resection for rectal cancer: short-term outcomes at a single center

BACKGROUND

The safety and feasibility of robotic-assisted multivisceral resection for locally advanced rectal cancer remain unclear. The aim of this study was to assess the short-term outcomes of this procedure at our institution.

METHODS

From December 2011 to December 2016, patients who underwent robotic-assisted multivisceral resection for rectal cancer were investigated. Patient demographics, treatment characteristics, perioperative outcomes, and pathological results were evaluated retrospectively.

RESULTS

There were 31 patients; 17 men (54.8%) and 14 women (45.2%), with a median age of 65 years (range 40-82 years). Twenty-one patients (67.7%) had a cT4 tumor, 9 patients (29.0%) had a pT4b tumor, and all patients except one (96.8%) underwent complete resection of the primary tumor with negative resection margins. Eleven patients (35.5%) received neoadjuvant chemoradiation. The most commonly resected organ was the vaginal wall (n = 12, 38.7%), followed by the prostate (n = 10, 32.3%). Lateral lymph node dissection was performed in 20 patients (64.5%). The median operative time was 394 min (range 189-549 min), and the median blood loss was 41 mL (range 0-502 mL). None of the patients received intraoperative blood transfusions or required conversion to open. Overall, postoperative complications occurred in 11 patients (35.5%). The most frequent complication was urinary retention (n = 5, 16.1%), and none of the patients developed serious complications classified as Clavien-Dindo grades III-V.

CONCLUSIONS

Robotic-assisted multivisceral resection for rectal cancer is safe and technically feasible.

Impact of porcine epidemic diarrhea on herd and individual Berkshire sow productivity

Porcine epidemic diarrhea (PED) is an emerging disease of pigs in several countries. In the present study, individual sow productivity of Berkshire sows exposed to PED virus at different stages of production was compared. On a commercial farrow-to-finish farm in Kagoshima Prefecture, Japan, the clinical presence of PED was observed in the farrowing barn on January 6, 2014, and all gilts and sows were immunized on January 9, except those in the farrowing barn. The sows were categorized into six groups based on the period in which they were exposed to PED virus: between days 0–30 (G1), 31–60 (G2), 61–90 (G3), or after 91 days of pregnancy (G4), during lactation (L), and after weaning (W). The control group was not exposed to PED during the period of PED outbreak. The study was based on 574 production records. The sows of the G4 and L groups had the fewest piglets weaned (4.8 ± 0.4, and 4.0 ± 0.3 pigs, respectively; P < 0.05) and the greatest pre-weaning mortality (33.1 ± 4.8%, and 39.7 ± 4.1%, respectively; P < 0.05). The number of piglets weaned and pre-weaning mortality, however, did not differ among the G1, G2, G3, and uninfected groups. The G4 and W groups had slightly lesser farrowing rates than the uninfected group (P < 0.05), however, similar subsequent piglet litter performance as the uninfected group. In conclusion, the effect of PED on individual sow productivity differed with the production stage in which sows were exposed to PED virus.

HMG-CoA reductase inhibitors reduce matrix metalloproteinase-9 activity in human varicose veins

Matrix metalloproteinases (MMPs) have been implicated in tissue degradation in varicose veins. The aim of this study was to investigate the effects of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) on the activity of MMPs in varicose veins. MMP-9 was present at significantly higher levels in varicose veins than in controls and was localized mainly in smooth muscle cells at the tunica media, where marked degradation of the extracellular matrix was observed. Both simvastatin and pravastatin strikingly suppressed MMP-9 activity in ex vivo culture of varicose veins. Simvastatin suppressed MMP-9 at both the mRNA and protein levels as well as at the urokinase-type plasminogen activator protein level, resulting in the dramatic suppression of MMP-9 activity induced by tumor necrosis factor-alpha. Therefore, statins suppress MMP-9 activity by multiple mechanisms in varicose veins, suggesting they may have clinical potential for the treatment of this disease.

Identification of a H+/glucose and galactose symporter gene glt from Xanthomonas oryzae pv. oryzae

We identified a glucose and galactose transporter gene from the plant-pathogenic bacterium Xanthomonas oryzae pv. oryzae. Sequence analysis indicated that the gene, named glt, encoded a polypeptide of 592 amino acid residues and the product was significantly homologous with members of the Na+/glucose cotransporter (SGLT) family from mammalian and bacterial origin, especially with vSGLT from Vibrio parahaemolyticus (50% identity). GLT functioned as a glucose and galactose transporter in an Escherichia coli mutant deficient in glucose and galactose transport activity. A protonophore inhibited the transport activity, suggesting that GLT is a H+-coupled glucose/galactose symporter.

Comparison of heavy metal concentrations in human umbilical cord in 1980 and 1990

The well-known Minamata disease was caused by mercury; the Itai-Itai disease by cadmium; and lead poisoning by gasoline additives. Following our previous investigation on heavy metal concentrations in the umbilical cords in 1980, total mercury, cadmium and lead concentrations in the umbilical cords (from 20 males and 20 females) have been measured in 1990 for comparison in the present study. The changes in metal concentrations in 1980 and 1990 were: from 0.007 +/- 0.005 microgram/g to 0.011 +/- 0.008 microgram/g for total mercury; from 0.019 +/- 0.016 microgram/g to 0.006 +/- 0.005 microgram/g, from 0.151 +/- 0.123 microgram/g to 0.046 +/- 0.038 microgram/g for lead. Total mercury accumulated in the umbilical cords increased to approximately 1.6-fold, while cadmium and lead decreased to approximately 1/3-fold during these 10 years.

Successful management of a giant spinal arteriovenous malformation with multiple communications between primitive arterial and venous structures by embolization: report of a case

A 47-year-old woman was admitted to our hospital with a giant spinal arteriovenous malformation (AVM) causing heart failure and thoracic myelopathy. Angiography revealed that the spinal AVM had multiple feeding vessels branching from the 5th through 12th intercostal arteries. The drainage vein flowed to the azygos vein and superior vena cava. The AVM destroyed the 7th thoracic vertebra. The cardiac output was 16.7l/min and the shunt ratio was 64% before treatment. Embolization with cyanoacrylate was performed because the operation was considered to be associated with a significant risk of paraplegia and organ ischemia. The cardiac output decreased to 11.6l/min and the shunt ratio was reduced to 32%. After embolization the patient demonstrated no symptoms of either heart failure or sensory deficits. During embolization, provocative tests using sodium amytal and lidocaine with magnetic stimulation were also performed. The above findings suggest that provocative tests and magnetic stimulation are useful to predict paraplegia, which could result from embolization while, in addition, embolization is considered to be a useful treatment for multiple shunt and nidus in this region.

Effect of E5510 on anastomotic intimal hyperplasia and platelet aggregation in dogs

We examined the effect of an antiplatelet agent, E5510, which inhibits both platelet aggregation and release of platelet-derived growth factor (PDGF), on anastomotic intimal hyperplasia and platelet aggregation. Twenty Beagle dogs underwent infrarenal aortic reconstruction with an expanded polytetrafluoroethylene (ePTFE) graft 5 mm in diameter and 3 cm long. The dogs were divided into three groups: placebo (control group, 7 dogs), E5510 1 mg/day (1-mg group, 6 dogs), and E5510 4 mg/day (4-mg group, 7 dogs). E5510 was administered orally 2 h before operation and once daily for 3 months after operation. Grafts were harvested 3 months after operation. All 13 grafts in the treated groups remained patent without evidence of intimal hyperplasia, whereas only 4 of 7 grafts (57%) remained patent in the control group, including 1 graft with > 50% stenosis. Three occluded grafts showed severe intimal hyperplasia at the anastomoses. The platelet aggregation ratio (PAR) with collagen (100 micrograms/ml) before drug administration at 3 months in the 4-mg group was significantly lower than that in the control and 1-mg groups. PAR after drug administration at 3 months in the 1- and 4-mg groups was significantly lower than that in the control group. Intimal thickness at the distal anastomosis was 817 +/- 190 microns in the control group, 240 +/- 80 microns in the 1-mg group, and 197 +/- 28 microns in the 4-mg group. Intimal thickness in the control group was significantly greater than that in the 1- and 4-mg groups. Smooth muscle cell (SMC) values in the intima at the distal anastomosis were 65.6 +/- 4.4% extinction (%E) in the control group, 47.6 +/- 3.4%E in the 1-mg group, and 51.3 +/- 3.5%E in the 4-mg group. SMC value in the control group was significantly greater than that in the 1- and 4-mg groups. E5510 inhibited PAR and reduced the degree of anastomotic intimal hyperplasia.

Changes in angiographic features and the ankle/brachial pressure index of femorodistal arterial bypass grafts during knee flexion

Systolic ankle pressure was measured in limbs in the extended and 90 degrees-flexed positions in three groups of patients who had undergone below-knee femorodistal arterial bypass. Group 1 consisted of eight limbs in seven patients who had received an autologous saphenous vein (ASV) graft; group 2 consisted of seven limbs in seven patients who had received a ringed expanded polytetrafluorethylene (ePTFE) graft; and group 3 consisted of five limbs in five patients who had received a reinforced biosynthetic borine collagen vascular (Omniflow) graft. Intravenous digital subtraction angiography was performed within 3 months of implantation. The ankle/brachial index (ABI) was significantly lower when the knee was flexed than when it was extended in group 1 and 3, but not in group 2. The ABI flexion in group 1 was similar to that in group 2. Morphologic changes such as kinking were demonstrated angiographically in groups 1 and 3. Given that the ABIs in groups 1 and 2 were similar with the knee flexed, despite the morphologic changes in group 1, we concluded that saphenous vein and ringed ePTFE grafts are more durable when subjected to acute knee flexion than Omniflow grafts. Thus, as graft failure is unlikely to result from kinking as a result of knee flexion alone, further clinical studies are required to elucidate the precise causes of graft failure.

Secular changes of PCB concentration accumulated in organs and tissues of Japanese from 1974 to 1989

The concentration and component types of PCB in adult human liver and fat tissue (64 samples) from forensic autopsy cases of Osaka Prefecture in 1989 were measured for comparison with the data for the same organ and tissue during the period from 1974 to 1984. The mean values of PCB levels in 1989 were 0.06 microgram/g (whole base) in the liver and 2.20 micrograms/g (fat base) in the fat tissue. These concentrations both were the same as those observed for the 15-year period. The percentages of the 5,6-chlorinated compound of PCB in the liver and fat tissue were lower but those of the 7-chlorinated compound were 15-20% higher.

Estimation of age from soft X-ray findings of Japanese pubic symphysis based on a image processing

A method for estimating the age at death through the image processing of soft X-ray pictures of pubic symphysis is reported. The collected 533 materials were sliced at the thickness of 5 mm. Prior to the image processing, subjective assessment was made on the five indices of gross morphological findings. The pictures showed roughening and darkening tendencies with age and two indices for image processing were introduced. Applying the natural logarithm to data obtained by the image processing and making regression analysis. two kinds of age estimation equations were derived in the form of; Y = -39.91 lnX + 189.63 and the estimated age Y was proportional to natural logarithm of measured indices X. The age estimation equations showed accuracies of 70% or more for the age range of +/- 5 years and 100% for +/- 8 years. The accuracy was satisfactory for age estimation in the field of person appraisal in legal medicine.

Estimation of age from image processing of soft X-ray findings in Japanese male thyroid cartilages

A method was developed for estimating the age at death based on image processing of soft X-ray pictures of thyroid cartilage from Japanese males. Data for 501 individuals were used to derive equations for this determination. Prior to image processing, gross morphological findings were used for estimation. Soft X-ray pictures indicated ossification with age and one index for image processing was introduced. The exponential function was applied to age estimation.

Estimation of age from soft X-ray findings of Japanese females thyroid cartilages

A method for estimating the age at death using the image processing of soft X-ray pictures of the thyroid cartilages of Japanese females was examined. The soft X-ray pictures showed increasing ossification with age. One index for image processing was introduced. It is ossification rate (OSFR). Corresponding to this index, one age estimation equation was obtained. This age estimation equation showed accuracies of 60% or more for the age range of +/- 5 years and about 80% for the age range of +/- 8 years.

Autopsy cases of giant heart during the past ten years in Osaka (1985-1994)

We collected data from 30 autopsied cases, in which the heart weight were 800 g or more (maximum 1,300 g), at the Osaka Medical Examiner's office, for past 10 years. Among these cases, the cause of death was cardiac failure in 17 cases (56.7%), followed by pulmonary diseases (3 cases, 10.0%), cerebral infarction (3 cases, 10.0%), and aortic rupture (2 cases, 6.6%). The mean weight of the giant hearts was 880 g (about 77% of the cases) and 4 cases (13%) had 1,000 g or more. The mean height of the giant heart victims was close to the standard level, and thus the mean level of the ratio of heart weight to height were about 2.5 times higher than the standard levels. The liver weights were also greater by 500-1,000 g than the standard levels.

Ringed grafting for an abdominal aortic aneurysm in a 92-year-old patient: report of a case

We report herein the case of a 92-year-old man with an abdominal aortic aneurysm who underwent successful surgical resection using a ringed graft. His postoperative course was uneventful, and he was discharged after 42 days, following which he attended the outpatient department twice a month for regular check-ups. He finally died of pneumonia which developed from an upper respiratory tract infection 6 months after his operation. Thus, surgical treatment should always be considered when an aneurysm is detected, even in very aged patients for whom the activities of daily living are possible.

[Study on secular changes of cadmium concentration accumulated in main organs of Japanese]

With the development of the mining and manufacturing industries and the petrochemical industry, cadmium (Cd) has been used not only for metal products but also petroleum products. Recently, environmental pollution due to waste fluids and gases from factories using cadmium and also domestic waste materials has become a cause for concern. In this connection, studies on the accumulated levels of Cd in the human body, its age-distribution in the general population and its secular changes during the last decade would be useful for clarifying the degree of contamination in the human body and providing an index which could be used as a basis for preventive measures against environmental pollution. For this purpose, the levels of Cd accumulated in main organs of the human body were determined using forensic data 3 times at 5-year intervals starting in 1976. The age intervals starting in 1976. The age group having the highest Cd level was 50-59 years, old and the mean weights of Cd per wet weight of heart, liver and kidney were 0.421, 2,984 and 56.43 micrograms/g, respectively. Each of these organs in babies less than a year old exhibited lower Cd levels, but teenagers had levels close to those in adult. However, the level in each organ was lower in individuals over 60 years old. 4 distinct age-related increase in the level of Cd was found only in the kidney. The levels of accumulated Cd in the liver and kidney showed a rise during the last 10 years from 2.358 to 5.568 micrograms/g and from 43.95 to 73.47 micrograms/g, respectively, whereas the Cd level in the heart has remained about the same, i.e. from 0.207 to 0.181 micrograms/g.

Studies on secular changes in the concentration of lead accumulated in organs and rib of Japanese

As environmental pollution due to waste fluids and gases from factories using lead (Pb), as well as domestic waste materials, has become a matter for public concern, studies on the accumulated levels of Pb in man have become necessary for defining the degree of contamination in the ordinary population. For this purpose, Pb levels in tissues of 76 forensic cadavers were determined in order to investigate the age distribution of accumulated Pb, and 120 samples were used to clarify secular changes in Pb accumulation during the last decade in the general population. The age group showing the highest Pb level was 50-59 years, with mean Pb contents per unit wet weight of 0.262, 0.520, 0.427 and 4.479 micrograms/g for heart, liver, kidney and rib, respectively. Each of these organs in all age groups exhibited almost the same Pb levels, but babies less than one year old had levels close to those in adults. However, ribs in babies exhibited much lower Pb levels. The levels in each organ were lower in individuals over 60 years old. A distinct age-related increase in Pb levels was found only in ribs from age 0 year to 50-59 years. The Pb levels in the heart, liver, kidney and rib showed a decrease during the last 10 years from 0.188 +/- 0.073 to 0.006 +/- 0.003 micrograms/g, from 0.307 +/- 0.169 to 0.076 +/- 0.057 micrograms/g, from 0.287 +/- 0.145 to 0.021 +/- 0.011 micrograms/g and from 3.203 +/- 1.477 to 2.366 +/- 1.469 micrograms/g, respectively.

[The fate of patients with intermittent claudication-comparison of surgical and non-surgical treatment]

The purpose of this study was to determine the operative indication for patients with intermittent claudication because of arteriosclerosis obliterans, and to compare the late result of the surgical treatment group (182 cases, 250 limbs) with that of the non-surgical treatment group (35 cases, 43 limbs). There were 3 operative deaths and 34 late deaths in the surgical group, and 14 late deaths in the non-surgical group. The number one cause of death was heart failure, including ischemic heart disease, in both groups. The 4-year cumulative patency rates were 91% in the aorto-iliac, 71% in the femoro-distal and 79% in the aorto-femoro-distal arterial reconstructions. Long term symptom free rates of the surgical group and the non-surgical group, except fatal case, were 83% and 44% in the aorto-iliac, 79% and 27% in the femoro-distal, 87% and 33% in the aorto-femoro-distal arterial regions, respectively. Late result of intermittent claudication in the surgical group was better than that in the non-surgical group. We concluded that intermittent claudication should be considered to be the indication for surgery, except for the cases with high risk diseases or malignant diseases.

[A case of immotile cilia syndrome accompanied by retinitis pigmentosa]

A case of immotile cilia syndrome accompanied by retinitis pigmentosa is reported. This syndrome involves congenital ciliary ultrastructural abnormality. A 27-year-old male complained of repeated pneumonia, sinusitis, and middle otitis. In addition, he had sperm motor insufficiency and electron microscopic finding of cilia led to the diagnosis of the present syndrome. Both fundi presented remarkable degeneration of retinal pigment epithelium and choroid and marked arterial narrowing. Constriction of the visual field and extinguished ERG were also noted. Abnormality of cilia of the retinal pigment epithelium was suggested. It was proposed that retinitis pigmentosa may be caused by abnormal cilia of the retinal pigment epithelium.

Some properties of fibroblasts from a patient with debrancher deficiency

Glycogenosis Type III is characterized by a deficiency of debranching enzyme (amylo-1,6-glucosidase, E.C. 3. 2. 1. 33) in most tissues. Low activity of liberating glucose from limited dextrin in the biopsied muscle can be demonstrated in a patient with this disease. We cultured fibroblasts from a skin biopsy from a patient with debrancher deficiency and examined the metabolism of glycogen in these cultured fibroblasts. Debrancher activity in the post-mitochondrial supernatant obtained from these fibroblasts showed a good concentration dependent manner but had approximately half of that from normal human fibroblasts (YH-1). Although the enzymatic activity of debrancher in the cultured fibroblasts from the skin was reduced essentially to the same levels as observed in muscle biopsy, little glycogen granules were accumulated in the cytoplasm of these fibroblasts as revealed by either light- or electron-microscopic observation. The fibroblasts obtained in the present study may be useful for the analysis of molecular mechanism of the debrancher deficiency disease, glycogenosis Type III.

Simultaneous activation of heat shock protein (hsp 70) and nucleolin genes during in vivo and in vitro prereplicative stages of rat hepatocytes

Rapidly growing cells usually have high levels of ribosome biogenesis. The sequential expression of protooncogenes during the transition of quiescent hepatocytes to the replicative stage was assumed to be followed by activation of cellular genes related to cell growth such as ribosome biosynthesis. First, the expression of major nucleolar protein (nucleolin or C23) and major heat-shock protein (hsp 70) genes was examined during rat liver regeneration. hsp 70 may function in cell growth and has a characteristic nucleolar location after heat shock. Both nucleolin and hsp 70 mRNA began to increase simultaneously after peaks of c-fos and c-myc, showed a peak 6 h after partial hepatectomy, and declined to the control levels around 20 h. That is, the peaks of nucleolin and hsp 70 mRNA precede the peak of ribosome formation (12-20 h) and DNA replication (24 h). Second, the behavior of nucleolin and hsp 70 mRNA was examined in primary cultured hepatocytes during their G0-G1 transition. Although the amounts of c-myc mRNA reached a plateau around 20 h after the initiation of culture and remained at these levels, DNA synthesis has never been found to start without the addition of EGF and insulin to this system. Both nucleolin and hsp 70 mRNA began to increase at around 20 h (prereplicative stage) and simultaneously decreased in inverse proportion to DNA synthesis induced by these growth factors. Thus, it is possible that the simultaneous enhancement of nucleolin and hsp 70 genes as described above is not merely coincidental, but is important biologically during the transition of quiescent hepatocytes to proliferative cells.

Variations of activities in the segments of respiratory chain among tissues in a patient with mitochondrial encephalomyopathy

Enzymatic activities of NADH cytochrome c reductase and cytochrome c oxidase were determined in the mitochondria from various tissues of a patient with mitochondrial encephalomyopathy and compared with those of controls. NADH cytochrome c reductase in the present patient decreased significantly in the liver and spleen and to a less extent in the kidneys. On the other hand, cytochrome c oxidase of the patient decreased severely in the skeletal muscle and kidneys and partially in the heart. Difference spectrum of reduced-minus oxidized form of mitochondria from patient's skeletal muscle and heart showed a decrease of cytochrome aa3 peak in the alpha region at 605 nm. These results indicate that there are cryptic deficiencies in the segments of the respiratory chain in the mitochondria from several tissues of the present patient, such as liver, kidney, spleen without any clinical manifestation. The weakness and atrophy of skeletal muscle was, however, well correlated to the biochemical analysis.

Glutathione contents in rat livers after acute and chronic exposure to ethylene oxide

Wistar rats were subjected to a 6 hr exposure to ethylene oxide once at the concentration of 500 ppm, 3 times a week for 12 weeks as a chronic experiment. Hepatic glutathione contents were determined after these treatments. The specific content of reduced form of glutathione (GSH) in the rat livers of chronic exposures was 28.9 nmoles/mg protein, which is not significantly different from that of control group. On the other hand, the hepatic content of GSH in rats subjected to a 4 hr exposure to ethylene oxide at a concentration of 2500 ppm decreased markedly to the levels of 5% of control value. The present results suggest the involvement of glutathione, at least in part, in the detoxication of ethylene oxide.

Reversion to bacillary forms of Serratia marcescens spheroplasts induced by carbenicillin. Scanning electron microscopic study

Bacterial cells of Serratia marcescens were easily induced to form spheroplasts in liquid medium by the addition of carbenicillin. The spheroplasts were unable to divide, but they were able to revert to the bacillary forms in liquid medium not containing carbenicillin. Four phases of the reversion sequence could be differentiated by scanning electron microscopy. (1) After 3 hr of incubation in carbenicillin-free medium, some projections arose out of the spheroplasts, and grew and elongated. (2) Their elongation resulted in a morphological change in the spheroplasts from spherical bodies to long irregular bacillary forms. (3) Further incubation caused several constricted areas in the bacillary form. (4) The long bacillary forms split along the constricted areas to become the parent bacillary forms of S. marcescens. When the long bacillary form that developed during the reversion was retreated with carbenicillin, it was immediately induced to become a spheroplast again.

Measurement of Mercury Methylation in Lake Water and Sediment Samples

Biological mercury methylation was assayed by a new radiochemical technique in the water column and sediments of a mercury-contaminated lake. In 24 weeks during 1979, there were three episodes of methylating activity in surface floc and in water, each lasting 3 to 5 weeks. Periods of methylation in the water column coincided with surface sediment methylation and appeared to be related to overall microbial activity. Mercury was actively methylated in the presence of bound sulfide.

Mercury methylation by fish intestinal contents

A new radiochemical method has been applied to the examination of mercury methylation in fish intestinal contents. Intestinal contents of six freshwater fish species were found capable of converting 203Hg2+ to CH3203Hg+. This activity was observed in fish from five of six lakes tested whether or not there was mercury pollution. Bacterial activity in the intestinal contents is most likely responsible for this methylation. Methylating activity of piscivors increased with decreasing quantity of intestinal contents. Generally, pike and walleye intestinal contents methylated a larger fraction of 203Hg2+ than those of whitefish and suckers. These data contradict the previous general conclusion that there is no mercury methylation in fish.