Acidity and conductivity of precipitation on central Long Island,New York in relation to meteorological variables

Three years of hourly sequential precipitation samples from central Long Island, New York were analyzed to determine the relationships between acidity and conductivity and concentrations of sulfate, nitrate plus nitrite, nitrogen in ammonium, sodium, and chloride ions. Relationships between precipitation acidity and meteorological conditions were also studied. Hydrogen ion concentrations are similar to those elsewhere in the northeastern United States. They are best correlated with sulfate concentrations but also correlate with concentrations of nitrogen in nitrate plus nitrite and nitrogen in ammonium ion. Concentrations are highest in the summer, with cold front and squall line precipitation and with rain showers and thundershowers. All ions measured contributed to sample conductivity but hydrogen ion contributed the most with sulfate ion second. Conductivity calculated from concentrations of the separate ions agreed well with measured conductivity. Conductivity showed relationships to meteorological conditions similar to those of hydrogen ion concentration except when sodium and chloride ions predominated in the sample.     

Mechanisms of Infertility Associated with Clinical and Subclinical Endometritis in High Producing Dairy Cattle

Clinical and subclinical endometritis are common causes of infertility and subfertility in high producing dairy cattle, delaying the onset of ovarian cyclic activity after parturition, extending luteal phases and reducing conception rates. Escherichia coli and Arcanobacterium pyogenes cause endometrial damage and inflammation. Components of microbes, such as lipopolysaccharide (LPS), are detected by Toll-like receptors on endometrial cells, leading to secretion of cytokines, chemokines and antimicrobial peptides. Long luteal phases associated with endometritis are probably caused by a switch in endometrial prostaglandin production from prostaglandin F_2a (PGF) to prostaglandin E₂. In addition, LPS impairs the function of the hypothalamus and pituitary, and directly perturbs ovarian granulosa cells steroidogenesis, providing mechanisms to explain the association between uterine disease and anovulatory anoestrus. Cows with uterine disease that ovulate have lower peripheral plasma progesterone concentrations that may further reduce the chance of conception associated with endometritis.     

Clinical remission of idiopathic hypereosinophilic syndrome in a Rottweiler

Idiopathic hypereosinophilic syndrome (HES) is a rare syndrome for which Rottweilers appear to over-represent the canine cases. A 6-month-old female entire Rottweiler presented with seizures following a traumatic incident. The dog was identified as having a marked, sustained eosinophilia and investigations did not identify an underlying cause. Concurrently, the dog had chronic eosinophilic hepatitis with impaired liver function and mesenteric eosinophilic lymphadenitis. The dog went on to have spontaneous resolution of HES and normal liver function was subsequently documented. To date, the dog is still alive, more than 4 years after initial presentation. The diagnosis of idiopathic HES in Rottweilers may not carry a poor prognosis and the condition may spontaneously resolve, even in cases with documented organ damage.     

Evidence for Parachlamydia in bovine abortion

Bovine abortion of unknown infectious aetiology still remains a major economic problem. In this study, we focused on a new possible abortigenic agent called Parachlamydia acanthamoebae. Retrospective samples (n=235) taken from late-term abortions in cattle were investigated by real-time diagnostic PCR for Chlamydiaceae and Parachlamydia spp., respectively. Histological sections of cases positive by real-time PCR for any Chlamydia-related agent were further examined by immunohistochemistry using specific antibodies. Chlamydophila abortus was detected only in three cases (1.3%) by real-time PCR and ArrayTube Microarray playing a less important role in bovine abortion compared to the situation in small ruminants in Switzerland. By real-time PCR as many as 43 of 235 (18.3%) cases turned out to be positive for Parachlamydia. The presence of Parachlamydia within placental lesions was confirmed in 35 cases (81.4%) by immunohistochemistry. The main histopathological feature in parachlamydial abortion was purulent to necrotizing placentitis (25/43). Parachlamydia should be considered as a new abortigenic agent in Swiss cattle. Since Parachlamydia may be involved in lower respiratory tract infections in humans, bovine abortion material should be handled with care given the possible zoonotic risk.     

Membrane phosphatidylserine regulates surface charge and protein localization

Electrostatic interactions with negatively charged membranes contribute to the subcellular targeting of proteins with polybasic clusters or cationic domains. Although the anionic phospholipid phosphatidylserine is comparatively abundant, its contribution to the surface charge of individual cellular membranes is unknown, partly because of the lack of reagents to analyze its distribution in intact cells. We developed a biosensor to study the subcellular distribution of phosphatidylserine and found that it binds the cytosolic leaflets of the plasma membrane, as well as endosomes and lysosomes. The negative charge associated with the presence of phosphatidylserine directed proteins with moderately positive charge to the endocytic pathway. More strongly cationic proteins, normally associated with the plasma membrane, relocalized to endocytic compartments when the plasma membrane surface charge decreased on calcium influx.     

Trickle irrigation: Predominant bacteria in treated Colorado River water and biologically clogged emitters

Summary Bacterial numbers and predominant bacterial types were determined in trickle irrigation systems receiving treated Colorado River water. Fourteen bacterial genera were isolated and identified from 86 water and sediment samples collected from trickle emitter systems receiving six water treatments. The bacteria identified were common aquatic and soil microbes and the genera in order of prevalence were Pseudomonas, Flavobacterium, Vibrio, Brevibacterium, Micrococcus, and Bacillus. A greater diversity of bacterial types was found in water that was sand filtered and received no chemical treatment. Regardless of the water treatment, Pseudomonas stutzeri was the predominant bacterium followed by Flavobacterium lutescens. The data indicated that pigmented bacteria, F. lutescens and ytophaga hutchinsonii caused the yellow color of the slime deposits in biologically clogged emitters; and, their growth was presumably supported by P. stutzeri., a nonpigmented bacterium. The occurrence of Bacillus sp. was enhanced by sand and screen filtration and markedly reduced by chemical conditioning the water with either chlorine and acid or acid alone. No strictly anaerobic bacteria, such as Clostridium sp., were detected in water treated with chlorine and acid. Iron bacteria, Sphaerotilus spp., were not detected in any water or sediment samples from trickle irrigation systems.Contribution from the U.S. Department of Agriculture, Science and Education Administration, Agricultural Research