Effects of ensiling time on corn silage starch ruminal degradability evaluated in situ or in vitro.

Accurate measurements of concentration and ruminal degradability of corn silage starch is necessary for formulation of diets that meet the energy requirements of dairy cows. Five corn silage hybrids ensiled for 0 (unfermented), 30, 60, 120, and 150 d were used to determine the effects of ensiling time on starch degradability of corn silage. In addition, the effects of grind size of silage samples on 7-h in vitro starch degradability and the relationship between in vitro, in situ and near-infrared reflectance spectroscopy (NIRS) starch degradability were studied. In situ disappearance of corn silage starch increased from 0 to 150 d of ensiling, primarily as a result of an increase in the washout or rapidly degraded fraction of starch, particularly during the first 60 d of ensiling. When analyzed in vitro and by NIRS, ensiling time increased corn silage starch degradability either linearly or to a greater extent during the first 2 mo of ensiling. Differences in in situ starch disappearance among corn silage hybrids were apparent during the first 2 mo of ensiling but were attenuated as silages aged. No differences among hybrids were detected using a 7-h in vitro starch digestibility approach. Results from the in vitro subexperiment indicate that 7-h in vitro starch degradability was increased by reducing grind size of corn silage from 4 to 1 mm, regardless of ensiling duration. Fine grinding corn silages samples (i.e., 1-mm sieve) allowed distinguishing low- from medium- and high-starch degradability rated hybrids. Correlations among in situ, in vitro and NIRS measurements for starch degradability were medium to high (r ≥0.57); however, agreement among methods was low (concordance correlation coefficient ≤0.15). In conclusion, ensiling time linearly increased degradation rate of corn silage resulting in greater in situ starch disappearance after 150 d of ensiling. Reductions in grind size from 4 to 1 mm resulted in greater in vitro starch degradability, regardless of ensiling duration. Strong correlation but low agreement between starch degradability methods suggest that absolute estimations of corn silage starch degradability will vary, but all methods can be used to assess the effect of ensiling time on starch degradability.

A European multicentre evaluation of detection and typing methods for human enteroviruses and parechoviruses using RNA transcripts.

Polymerase chain reaction (PCR) detection has become the gold standard for diagnosis and typing of enterovirus (EV) and human parechovirus (HPeV) infections. Its effectiveness depends critically on using the appropriate sample types and high assay sensitivity as viral loads in cerebrospinal fluid samples from meningitis and sepsis clinical presentation can be extremely low. This study evaluated the sensitivity and specificity of currently used commercial and in-house diagnostic and typing assays. Accurately quantified RNA transcript controls were distributed to 27 diagnostic and 12 reference laboratories in 17 European countries for blinded testing. Transcripts represented the four human EV species (EV-A71, echovirus 30, coxsackie A virus 21, and EV-D68), HPeV3, and specificity controls. Reported results from 48 in-house and 15 commercial assays showed 98% detection frequencies of high copy (1000 RNA copies/5 µL) transcripts. In-house assays showed significantly greater detection frequencies of the low copy (10 copies/5 µL) EV and HPeV transcripts (81% and 86%, respectively) compared with commercial assays (56%, 50%; P = 7 × 10-5 ). EV-specific PCRs showed low cross-reactivity with human rhinovirus C (3 of 42 tests) and infrequent positivity in the negative control (2 of 63 tests). Most or all high copy EV and HPeV controls were successfully typed (88%, 100%) by reference laboratories, but showed reduced effectiveness for low copy controls (41%, 67%). Stabilized RNA transcripts provide an effective, logistically simple and inexpensive reagent for evaluation of diagnostic assay performance. The study provides reassurance of the performance of the many in-house assay formats used across Europe. However, it identified often substantially reduced sensitivities of commercial assays often used as point-of-care tests.

Outcome-Based Comparison of Percutaneous Procedures for Urinary Lithiasis with Calibre of Instrumentation less than 12Fr.

Renal stone disease is becoming increasingly prevalent globally. With a rise in stone disease worldwide, there is also a relative increase in the rates of surgical intervention. Technological advances have allowed a move towards minimising the complications rates and length of stay with a reduction in invasiveness and size of instruments. A trend for minimising the percutaneous tract size has been noted in percutaneous nephrolithotomy (PCNL) for renal stones. The management has shifted from open surgery to standard PCNL, mini-PCNL and the latest ultra-mini and micro-PCNL techniques. There is a need to compare outcomes for the ever-advancing technologies, such as the smaller calibre of instruments, to assess risk-benefit in practice. This review looks at outcome-based comparison of percutaneous procedures for urinary lithiasis with instruments <12Fr in size.

The evolutionary history of ACE2 usage within the coronavirus subgenus Sarbecovirus.

Severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1) and SARS-CoV-2 are not phylogenetically closely related; however, both use the angiotensin-converting enzyme 2 (ACE2) receptor in humans for cell entry. This is not a universal sarbecovirus trait; for example, many known sarbecoviruses related to SARS-CoV-1 have two deletions in the receptor binding domain of the spike protein that render them incapable of using human ACE2. Here, we report three sequences of a novel sarbecovirus from Rwanda and Uganda that are phylogenetically intermediate to SARS-CoV-1 and SARS-CoV-2 and demonstrate via in vitro studies that they are also unable to utilize human ACE2. Furthermore, we show that the observed pattern of ACE2 usage among sarbecoviruses is best explained by recombination not of SARS-CoV-2, but of SARS-CoV-1 and its relatives. We show that the lineage that includes SARS-CoV-2 is most likely the ancestral ACE2-using lineage, and that recombination with at least one virus from this group conferred ACE2 usage to the lineage including SARS-CoV-1 at some time in the past. We argue that alternative scenarios such as convergent evolution are much less parsimonious; we show that biogeography and patterns of host tropism support the plausibility of a recombination scenario, and we propose a competitive release hypothesis to explain how this recombination event could have occurred and why it is evolutionarily advantageous. The findings provide important insights into the natural history of ACE2 usage for both SARS-CoV-1 and SARS-CoV-2 and a greater understanding of the evolutionary mechanisms that shape zoonotic potential of coronaviruses. This study also underscores the need for increased surveillance for sarbecoviruses in southwestern China, where most ACE2-using viruses have been found to date, as well as other regions such as Africa, where these viruses have only recently been discovered.

The evolutionary history of ACE2 usage within the coronavirus subgenus Sarbecovirus.

SARS-CoV-1 and SARS-CoV-2 are not phylogenetically closely related; however, both use the ACE2 receptor in humans for cell entry. This is not a universal sarbecovirus trait; for example, many known sarbecoviruses related to SARS-CoV-1 have two deletions in the receptor binding domain of the spike protein that render them incapable of using human ACE2. Here, we report three sequences of a novel sarbecovirus from Rwanda and Uganda which are phylogenetically intermediate to SARS-CoV-1 and SARS-CoV-2 and demonstrate via in vitro studies that they are also unable to utilize human ACE2. Furthermore, we show that the observed pattern of ACE2 usage among sarbecoviruses is best explained by recombination not of SARS-CoV-2, but of SARS-CoV-1 and its relatives. We show that the lineage that includes SARS-CoV-2 is most likely the ancestral ACE2-using lineage, and that recombination with at least one virus from this group conferred ACE2 usage to the lineage including SARS-CoV-1 at some time in the past. We argue that alternative scenarios such as convergent evolution are much less parsimonious; we show that biogeography and patterns of host tropism support the plausibility of a recombination scenario; and we propose a competitive release hypothesis to explain how this recombination event could have occurred and why it is evolutionarily advantageous. The findings provide important insights into the natural history of ACE2 usage for both SARS-CoV-1 and SARS-CoV-2, and a greater understanding of the evolutionary mechanisms that shape zoonotic potential of coronaviruses. This study also underscores the need for increased surveillance for sarbecoviruses in southwestern China, where most ACE2-using viruses have been found to date, as well as other regions such as Africa, where these viruses have only recently been discovered.

Galactose toxicity in the chick: hyperosmolality.

Galactose-fed chicks have been found to develop severe hyperosmolar dehydration. Although biochemical abnormalities have been observed in the brain of the galactose-toxic chick, the observed physiologic alteration of serum osmolality could be the major factor responsible for the galactose toxicity syndrome in the chick.

Biological Control of Yellow Nutsedge with the Indigenous Rust Fungus Puccinia canaliculata.

Yellow nutsedge (Cyperus esculentus L.) is a serious weed problem in the United States and other countries. An indigenous rust fungus [Puccinia canaliculata (Schw.) Lagerh.], pathogenic on yellow nutsedge, was released in early spring as a potential biological control agent. The fungus inhibited nutsedge flowering and new tuber formation. The fungus also dehydrated and killed nutsedge plants. The successful control of yellow nutsedge by a rust epiphytotic under experimental conditions demonstrates the potential use of the rust in an integrated weed management system.

Skeletal Muscle Metastasis to Vastus Lateralis from a Urothelial Carcinoma: A Case Report and Review of Its Diagnosis and Management.

Bladder cancer is a common genitourinary tract malignancy. Urothelial carcinoma is the most frequent type of bladder cancer and it commonly metastasises to lymph nodes, bone, lung and liver by a haematogenous route. Skeletal metastases are very rare and are usually present in patients with advanced metastatic disease. We present an unusual case of a 71-year-old male with a urothelial carcinoma metastasis to the vastus lateralis muscle 3 months following a cystoprostatectomy for muscle invasive bladder cancer.

Effect of collagen packing and moisture content on leather stiffness.

Applications for skin derived collagen materials, such as leather and acellular dermal matrices, usually require both strength and flexibility. In general, both the tensile modulus (which has an impact on flexibility) and strength are known to increase with fiber alignment, in the tensile direction, for practically all collagen-based tissues. The structural basis for flexibility in leather was investigated and the moisture content was varied. Small angle X-ray scattering was used to determine collagen fibril orientation, elongation and lateral intermolecular spacing in leather conditioned by different controlled humidity environments. Flexibility was measured by a three point bending test. Leather was prepared by tanning under biaxial loading to create leather with increased fibril alignment and thus strength, but this treatment also increased the stiffness. As collagen aligns, it not only strengthens the material but it also stiffens because tensile loading is then applied along the covalent chain of the collagen molecules, rather than at an angle to it. Here it has been shown that with higher moisture content greater flexibility of the material develops as water absorption inside collagen fibrils produces a larger lateral spacing between collagen molecules. It is suggested that water provides a lubricating effect in collagen fibrils, enabling greater freedom of movement and therefore greater flexibility. When collagen molecules align in the strain direction during tanning, leather stiffens not only by the fiber alignment itself but also because collagen molecules pack closer together, reducing the ability of the molecules to move relative to each other.

Data on collagen structures in leather with varying moisture contents from small angle X-ray scattering and three point bend testing.

The data presented in this article are related to the research article entitled "Effect of collagen packing and moisture content on leather stiffness" (Kelly et al., 2018). This article describes how moisture content affects collagen packing and leather stiffness. Structural changes were experimentally introduced into ovine leather through biaxial strain during tanning (׳stretch tanning׳). Leather samples produced normally without strain (׳non-stretch tanned׳) and those produced by stretch tanning, were conditioned in a range of relative humidity environments and then analysed by small angle X-ray scattering and three point bend testing. The collagen D-spacing, lateral intermolecular spacing and flexural properties were measured under these varying moisture contents.

Further Evidence for Bats as the Evolutionary Source of Middle East Respiratory Syndrome Coronavirus.

The evolutionary origins of Middle East respiratory syndrome (MERS) coronavirus (MERS-CoV) are unknown. Current evidence suggests that insectivorous bats are likely to be the original source, as several 2c CoVs have been described from various species in the family Vespertilionidae Here, we describe a MERS-like CoV identified from a Pipistrellus cf. hesperidus bat sampled in Uganda (strain PREDICT/PDF-2180), further supporting the hypothesis that bats are the evolutionary source of MERS-CoV. Phylogenetic analysis showed that PREDICT/PDF-2180 is closely related to MERS-CoV across much of its genome, consistent with a common ancestry; however, the spike protein was highly divergent (46% amino acid identity), suggesting that the two viruses may have different receptor binding properties. Indeed, several amino acid substitutions were identified in key binding residues that were predicted to block PREDICT/PDF-2180 from attaching to the MERS-CoV DPP4 receptor. To experimentally test this hypothesis, an infectious MERS-CoV clone expressing the PREDICT/PDF-2180 spike protein was generated. Recombinant viruses derived from the clone were replication competent but unable to spread and establish new infections in Vero cells or primary human airway epithelial cells. Our findings suggest that PREDICT/PDF-2180 is unlikely to pose a zoonotic threat. Recombination in the S1 subunit of the spike gene was identified as the primary mechanism driving variation in the spike phenotype and was likely one of the critical steps in the evolution and emergence of MERS-CoV in humans.IMPORTANCE Global surveillance efforts for undiscovered viruses are an important component of pandemic prevention initiatives. These surveys can be useful for finding novel viruses and for gaining insights into the ecological and evolutionary factors driving viral diversity; however, finding a viral sequence is not sufficient to determine whether it can infect people (i.e., poses a zoonotic threat). Here, we investigated the specific zoonotic risk of a MERS-like coronavirus (PREDICT/PDF-2180) identified in a bat from Uganda and showed that, despite being closely related to MERS-CoV, it is unlikely to pose a threat to humans. We suggest that this approach constitutes an appropriate strategy for beginning to determine the zoonotic potential of wildlife viruses. By showing that PREDICT/PDF-2180 does not infect cells that express the functional receptor for MERS-CoV, we further show that recombination was likely to be the critical step that allowed MERS to emerge in humans.

Effectiveness of health education to increase screening for cervical cancer among eastern-band Cherokee Indian women in North Carolina.

BACKGROUND: The North Carolina Native American Cervical Cancer Prevention Project was a 5-year, National Cancer Institute-funded trial of health education designed to increase screening for cervical cancer among Native-American women in North Carolina. PURPOSE: This study was conducted to evaluate the effectiveness of this education program in the Eastern-Band Cherokee target population. METHODS: Cherokee tribal lands were mapped and all households (N = 2223) were listed to ensure maximum coverage of the eligible population (women, aged 18 years and older, who were enrolled tribal members). Eligible women were identified by the use of a brief questionnaire administered to an adult member of the household. Of the 1279 households with eligible women, 1020 (79.8%) agreed to participate. The intervention was an individualized health education program delivered by female Cherokee lay health educators. The participants were randomly assigned to receive or not to receive the intervention (i.e., to program and control groups, respectively) by use of the Solomon Four-Group design. Data were collected in face-to-face interviews conducted in the participant's home. Of the 996 women who were ultimately enrolled, 540 were randomly assigned to receive a pretest (preintervention) interview that involved administration of a 96-item questionnaire designed to collect data on knowledge, intentions, and behaviors related to cervical cancer; of these 540 women, 263 were randomly assigned to receive the education program. The remaining 456 women did not receive the pretest, but 218 were randomly assigned to receive the education program. Six months after receiving the education program, the women in all four groups were administered a post-test that was identical to the pretest. Logistic regression was used to assess the effects of the pretest and the educational program. All P values resulted from two-sided statistical tests. RESULTS: Eight hundred and fifteen (81.8%) of the 996 participants completed the post-test interview. The remaining 181 women who were lost to follow-up were evenly distributed among the four study groups. At the post-test, 282 (73.2%) of the 385 women who received the education program reported having had a Pap smear following the intervention, compared with 275 (64%) of the 430 control subjects. Women who received the education program were more likely to answer all knowledge items correctly on the post-test (odds ratio [OR] = 2.18, 95% confidence interval [CI] = 1.08-4.39) and to report having obtained a Pap smear in the past year (OR = 2.06, 95% CI = 1.14-3.72) than women in the control groups. CONCLUSION: Women who received the education program exhibited a greater knowledge about cervical cancer prevention and were more likely to have reported having had a Pap smear within the past year than women who did not receive the program.

Isolation of a bone-resorptive factor from human cancer ascites fluid.

A protein fraction that induces the resorption of bone explants in organ culture was isolated from the ascitic fluid of patients with advanced cancer metastatic to the peritoneal cavity. Partial purification was achieved by means of gel filtration, affinity chromatography, and ion-exchange chromatography. The isolated fraction, the components of which have an apparent molecular weight of 60,000, was found to be heterogeneous by disc gel electrophoresis and to be composed primarily of proteins with relatively acidic electrophoretic properties. The specific bone-resorptive activity of this protein fraction was greatly increased over that of the unfractionated starting material, and the activity could be completely destroyed upon incubation with pronase and on heating. As determined by immunoassay and extraction procedures with various solvents, the bone-resorptive action of the isolated fraction was not attributable to the presence of parathyroid hormone, prostaglandin E2 or vitamin D-like sterols. In parallel experiments the supernatants of phytohemagglutinin-stimulated normal human peripheral leukocytes were subjected to identical chromatographic techniques, and a proten fraction with a molecular weight of 60,000, which resembled the resorptive fraction isolated from cancer ascites fluid and which contained significant bone-resorptive activity, was also partially purified.

Megestrol acetate versus tamoxifen in advanced breast cancer: 5-year analysis--a phase III trial of the Piedmont Oncology Association.

One hundred thirty-eight patients with recurrent or metastatic breast cancer were randomized to receive megestrol acetate 40 mg orally four times daily or tamoxifen 10 mg orally twice a day. Upon treatment failure patients were crossed over to the alternate treatment. Eligibility required that either the estrogen receptor (ER) or progesterone receptor (PR) be positive or that both values be unknown, and that the patients be at least 2 years post-spontaneous menopause or over 50 years of age. Pretreatment characteristics including performance status (PS), disease-free interval (DFI), receptor status, and prior treatment were similar for both groups. Only three patients had previous hormonal therapy while one third had prior chemotherapy. Objective response was determined using strict International Union Against Cancer (UICC) criteria. Seventeen of 61 patients achieved complete response (CR) or partial response (PR) on megestrol (28%) while 20 of 64 patients achieved CR or PR on tamoxifen (31%). Responses of skin and bone lesions were similar for both agents; however, more patients with visceral disease responded to tamoxifen. Response did not correlate with the level of ER or PR but was correlated with age. Both unadjusted and adjusted analysis of time to progression and adjusted analysis (for pretreatment variables) of survival showed significant differences favoring tamoxifen. Six of 44 patients (14%) crossed from megestrol to tamoxifen achieved CR or PR while only two of 38 patients (5%) crossed from tamoxifen to megestrol achieved response. Only one of the original patients randomized to megestrol remains on study, while 12 patients still remain on tamoxifen. These data indicate similar response rates for megestrol and tamoxifen; however, time to progression and overall survival significantly favor tamoxifen when used as first-line therapy in this trial.

Plant molecular biology in the space station era: utilization of KSC fixation tubes with RNAlater.

Spaceflight experiments involving biological specimens face unique challenges with regard to the on orbit harvest and preservation of material for later ground-based analyses. Preserving plant material for gene expression analyses requires that the tissue be prepared and stored in a manner that maintains the integrity of RNA. The liquid preservative RNAlater (Ambion) provides an effective alternative to conventional freezing strategies, which are limited or unavailable in current spaceflight experiment scenarios. The spaceflight use of RNAlater is enabled by the Kennedy space center fixation tube (KFT), hardware designed to provide the necessary containment of fixatives during the harvest and stowage of biological samples in space. Pairing RNAlater with the KFT system provides a safe and effective strategy for preserving plant material for subsequent molecular analyses, a strategy that has proven effective in several spaceflight experiments. Possible spaceflight scenarios for the use of RNAlater and KFTs are explored and discussed.

Repeat HIV testing: high-risk behaviour or risk reduction strategy?

OBJECTIVE: To examine the characteristics of repeat and first-time HIV testers and consider their implications for HIV test counselling. METHODS: An anonymous questionnaire was completed by nearly 1500 people seeking an HIV test between September 1997 and July 1998 at a same-day HIV testing clinic in London, United Kingdom. Repeat testers were those people who had previously tested HIV negative and were returning for another test. Information was collected on self-reported unprotected penetrative sex (UPS) in the previous 3 months and reasons for seeking the present test. RESULTS: Overall, 50.6% (721/1446) of all clinic attenders were repeat testers: gay men 71.7% (337/470), heterosexual men 42.1% (208/494) and heterosexual women 38.6% (186/482). No significant differences were found between repeat and first time testers in the frequency of UPS (P > or = 0.06). However, gay men (but not heterosexual men and women) reporting three or more previous HIV tests were significantly more likely to report higher-risk UPS (i.e. with a partner whose HIV status was either positive or unknown) (42.2%) than those who had had one-two or no previous tests (25.3 and 25.4%, respectively; P = 0.002). Over half the heterosexual men and women, and one third of gay men said they were seeking the current HIV test in preparation for a new relationship; these proportions did not differ significantly between repeat and first-time testers (P > 0.1). CONCLUSION: In this London HIV testing clinic, no significant differences were found in the frequency of UPS between repeat and first-time testers with the exception of gay men with a history of three or more previous HIV tests, who reported elevated levels of high-risk sexual behaviour. For many people, repeat HIV testing has become part of a risk reduction strategy to establish seroconcordance with a regular partner. HIV test counselling provides the opportunity both to address high-risk behaviour and to reinforce personal risk-reduction strategies.

Amelioration of vincristine neurotoxicity by glutamic acid.

Neurotoxicity is the principal limiting side effect of the widely used antitumor agent, vincristine. Following evaluation of glutamic acid as a potential modifier of vincristine toxicity in preclinical studies in mice and a preliminary clinical trial, a prospective, double-blind, placebo-controlled, randomized trial was conducted by the Piedmont Oncology Association. Of 87 patients entered into the study, 84 were evaluable, including 42 patients who were randomly assigned to receive vincristine 1.0 mg/m2 weekly for six doses and 42 patients who were assigned to receive glutamic acid 500 mg orally three times daily plus vincristine. The following neurotoxic signs and symptoms were evaluated before each dose of vincristine: reflex changes, paresthesias, constipation, strength, and mental changes. Loss of the Achilles tendon reflex, an objective parameter, was noted in 19 percent of patients receiving glutamic acid and 42 percent of control subjects (p = 0.03). Development of moderate to severe paresthesias, a subjective parameter, occurred in 19 percent of the glutamic acid group and 36 percent of the placebo group (p = 0.09). Overall moderate neurotoxicity (6 units or more), determined by adding the grade of each neurotoxic parameter for the weekly clinic visit in which maximum neurotoxicity occurred, was observed in 21 percent of patients receiving glutamic acid and 43 percent of those in the control group (p = 0.04). Hematologic and gastrointestinal side effects occurred with similar frequency in the two groups. The administration of glutamic acid has decreased vincristine-induced neurotoxicity without any attendant side effects.

Relative accretion of 99mTc-polyphosphate by forming and resorbing bone systems in rats: its significance in the pathologic basis of bone scanning.

The relative roles of osteogenesis andd osteolysis in the production of positive radionuclide images of skeletal lesions were investigated. The uptake of 99mTc-polyphosphate (Tc-PP) by each process was measured in an animal model that permitted bone formation and resorption to be studied independently. Ten rats received intramuscular implants of bone-forming demineralized matrix (DM) and resorbing devitalized bone (DV). Radiographs and Tc-PP scintiscans were made each week thereafter. At 6-10 weeks, the implants and normal bone samples were removed, counted for 99mTc, and examined histologically. The uptake of Tc-PP BY DM implants was first detected on images made 3 weeks after implanatation, and by DV implants, 1-2 weeks later. Serial radiography showed progressive calcification of DM an resorption of DV implants. Microscopic examinations of undecalcified sections, stained with a modified Goldner preparation, revealed vital-bone formation in the DM implants and osteoclastic resorption in the DV. Activity counts per gram of DM and DV implants were, respectively, 200% and 90% that of normal bone. Since only the bone-forming system (DM) accumulated Tc-PP at greater than normal concentrations, this study indicates that positive bone images of osteolytic lesions solely reflect compensatory osteogenic responses.

The Weissenbacher-Zweymüller syndrome: possible neonatal expression of the Stickler syndrome.

The Robin anomaly is a recognized presenting manifestation of the Stickler syndrome, an autosomal dominantly inherited disorder originally termed "hereditary progressive arthroophthalmopathy." We report an infant with the Robin anomaly, myopia and dumbbell-shaped femora and humeri in a family with the Stickler syndrome. This observation suggests that the Weissenbacher-Zweymüller syndrome is in fact a variant of the Stickler syndrome.