A reply to "Relevant factors in the eutrophication of the Uruguay River and the Río Negro".

A recent paper by Beretta-Blanco and Carrasco-Letelier (2021) claims that agricultural eutrophication is not one of the main causes for cyanobacterial blooms in rivers and artificial reservoirs. By combining rivers of markedly different hydrological characteristics e.g.

The identity of the Chilean Amphibians collected by the United States exploring expedition.

Between mid-May and early June of 1839, members of the United States Exploring Expedition collected diverse anurans in the environs of Valparaíso, Chile, later described by Girard in 1853. Of this set of species, Metaeus timidus, described there as a new genus and species, attracts attention because is a name that practically disappeared from the herpetological literature. Its identification, along with that of the other Chilean taxa collected by the USEE (Cystignathus nebulosus Girard, 1853, Pleurodema bibroni Tschudi, 1838, Pleurodema elegans Bell, 1843, Bufo lugubrosus Girard, 1853, Bufo thaul Lesson, 1826 and Metaeus timidus Girard, 1853) are the main objectives of this contribution.

Comments on the type locality, type series, and geographic distribution of Pseudopaludicola falcipes (Hensel, 1867) (Amphibia, Anura).

The genus Pseudopaludicola was erected by Miranda-Ribeiro, 1926 to accommodate Liuperus falcipes Hensel, 1867a. Currently, there are 18 recognized species of Pseudopaludicola, with 45% of the species described since 2003. Although Pseudopaludicola falcipes is the type species, Hensel's description lacked designation of type specimens for that species; furthermore, it was based on a series of 30 individuals (without collection numbers or indication of where were they deposited) from "Provinz S[ão].

High genetic diversity but low population structure in the frog Pseudopaludicola falcipes (Hensel, 1867) (Amphibia, Anura) from the Pampas of South America.

Relative to South America's ecoregions, the temperate grasslands of the Pampas have been poorly studied from a phylogeographic perspective. Based on an intermediate biogeographic setting between subtropical forest (Atlantic Forest) and arid ecosystems (Chaco and Patagonia), Pampean species are expected to show unstable demographic histories due to the Quaternary climatic oscillations. Herein, we investigate the phylogenetic relatedness and phylogeographic history of Pseudopaludicola falcipes, a small and common frog that is widely distributed across the Pampean grasslands.

The identity of Hyla leucotaenia Burmeister, 1861 (Anura: Hylidae).

The German naturalist Carl Hermann Conrad Burmeister (1807-1892) had a prolific scientific career, spanning multiple taxa from diverse insect groups and trilobites to temnospondyls, birds, and extant and fossil mammals (see Berg, 1895). His contributions to anuran taxonomy are concentrated in two books, "Erläuterungen zur Fauna Brasiliensis…" (Burmeister, 1856) and "Reise durch die La Plata-Staaten…" (Burmeister, 1861). The latter is an account of his travels in Argentina and Uruguay from 1857-1860 and includes descriptions of three new species of frogs: Leiuperus nebulosus, Cystignathus mystacinus, and Hyla leucotaenia.

Different molecular weight hyaluronic acid effects on human macrophage interleukin 1β production.

This study examined the effect of hyaluronan (HA) molecular weight on immune response. HA with molecular weights ranging from the unitary disaccharide unit (400 Da) up to 1.7 × 10(6) Da and with very low endotoxin contamination level (less than 0.

The identity of Rana margaritifera Laurenti, 1768 (Anura, Bufonidae).

Rana margaritifera was described by Laurenti in 1768 and currently is associated to the genus Rhinella, under the combination Rhinella margaritifera. Currently, the R. margaritifera species group consists of 16 recognized species.

Low molecular weight hyaluronic acid effects on murine macrophage nitric oxide production.

Hyaluronic acid (HA) is increasingly used for a number of medical device applications. Since the chemical structure of HA is identical no matter its bacterial or animal origin, it should be the ideal biomaterial. However, short term transient inflammatory reactions are common, while rare long-term adverse events may correlate with subclinical chronic inflammation.

Defining critical inflammatory parameters for endotoxin impurity in manufactured alginate microcapsules.

Since current purification methods cannot completely remove all traces of endotoxin in biomaterials intended for use in implantable or blood-contacting devices, acceptable levels of endotoxin contamination that will not cause a significant inflammatory reaction need to be defined. Inflammatory reactions to biomaterials may include production of high concentrations of potentially harmful nitric oxide (NO) generated by macrophages. Nitrite accumulation was measured from RAW264.

Screening biomaterials for functional complement activation in serum.

Complement plays an important role in the immune attack against invading microorganisms. However, blood-contacting medical device biomaterials lacking specific complement inhibitors, with free hydroxyl and/or amino groups, or with absorbed antibodies, may inappropriately activate complement. Inappropriate activation by either the antibody-mediated classical or the antibody-independent alternative pathway may have well-known acute or poorly understood chronic effects on the host or device.

Sensitivity of insulin production from encapsulated islets to endotoxin-stimulated macrophage inflammatory mediators.

Chronic inflammation may compromise function of implanted encapsulated islets. Increased purity of alginate used for encapsulation prolongs encapsulated graft function, correlating with decreased presence of impurities like bacterial endotoxin. Limits for endotoxin contamination in biomaterials based on indirect inhibition of function of embedded cells have yet to be established.

Screening biomaterials for stimulation of nitric oxide-mediated inflammation.

Inflammatory reactions to biomaterials may include macrophage-mediated generation of nitric oxide (NO), which may harm patient tissue or potentially interfere with proper function of an implanted device. RAW 264.7 cells were grown in culture and treated at various times with lipopolysaccharide (LPS, endotoxin), murine recombinant gamma-interferon (mrIFN-gamma), and different preparations of hyaluronic acid (HA).

Simple and effective method for generating single-stranded DNA targets and probes.

A simple and efficient PCR method was developed for generating dye- or radiolabeled single-stranded DNA targets or probes used for hybridization studies. The method involved the use of a pair of long primers with high annealing temperatures and a short, labeled primer with a low annealing temperature in a PCR consisting of two cycles at different temperatures. We used this method to generate dye Cy 5-labeled and [32P]-radiolabeled single-stranded DNA targets and probes.

Microarray and allele specific PCR detection of point mutations in Mycobacterium tuberculosis genes associated with drug resistance.

Global public health is threatened by the emergence of potentially dangerous antibiotic drug-resistant strains of Mycobacterium tuberculosis. Point mutations in certain M. tuberculosis genes are associated with the resistance of M.

Peptide nucleic acid probe detection of mutations in Mycobacterium tuberculosis genes associated with drug resistance.

The emergence of drug-resistant strains of Mycobacterium tuberculosis is a serious public health problem. Many of the specific gene mutations that cause drug resistance in M. tuberculosis are point mutations.

Role of serology in the diagnosis of Lyme disease.

Numerous concerns regarding the potential for misdiagnosis of Lyme disease using commercial assays have been voiced by the US Food and Drug Administration (FDA). We attempted to clarify the clinical value of serologic testing for Lyme disease using the results of commonly marketed assays for detecting antibody to Borrelia burgdorferi, the organism that causes Lyme disease. We reviewed published studies on B burgdorferi test performance published through 1998, package insert labeling from FDA-cleared test kits for B burgdorferi, and Lyme Disease Survey Set LY-A from the College of American Pathologists.

Issues and perspectives on the biocompatibility and immunotoxicity evaluation of implanted controlled release systems.

Over the past decade, significant advances and discoveries in cell and molecular biology and biomaterials have provided a foundation for the research and development of new, complex controlled release systems. Many of these new controlled release systems utilize active biological components, i.e.

Silicone breast implants and autoimmune disease.

In 1992, the Food and Drug Administration requested a voluntary moratorium on the scale and implantation of silicone-gel-filled breast implants because of growing concern over the lack of scientific and clinical data supporting their safety and effectiveness. Breast implants had been reported to cause serious local complications, and new questions about breast implants and increased risk for autoimmune disease, including the rare but sometimes fatal connective tissue disease scleroderma, were also raised. Since that time, clinical studies have focused on the adjuvant effect of silicone and of potential autoantibody production.

Biomaterials and Granulomas.

The rapidly expanding use of implants for reconstruction and repair of diseased or traumatized tissues and organs has fueled the search for biomaterials that are stable, nontoxic, and biologically inert. Unfortunately, implants frequently cause acute or chronic inflammation resulting in tissue damage and rejection. Inflammation usually occurs at the biomaterial-tissue interface and reflects surface adsorption of plasma proteins, complement activation, neutrophil and macrophage infiltration, hyperplasia, and release of inflammatory mediators and proteolytic enzymes.

Acquisition and generalization of social skills by high school students with mild mental retardation.

Initial acquisition of social skills by high school students with mild mental retardation was measured during the social skills training game Stacking the Deck. Generalization probes were conducted outside of the training setting (immediately preceding and following training, and 6 weeks posttraining). Due to the high degree of dissimilarity between stimuli in and outside of the training setting, we hypothesized that generalization of skills to nontraining environments would be minimal.

Differential permeability of the blood-tumour barrier in intracerebral tumour-bearing rats: antidrug antibody to achieve systemic drug rescue.

The feasibility of utilizing the differential permeability of the blood-tumour barrier to low- vs. high-molecular-weight compounds is demonstrated in a brain tumour model. Nude rats (n = 27) with or without intracerebral tumours received intravenous [3H]methotrexate (M(r) 454), followed 60 min later by antimethotrexate antibody (M(r) 150,000) or nonspecific mouse antibody.