Comparative assessment of satellite- and drone-based vegetation indices to predict arthropod biomass in shrub-steppes.

Arthropod biomass is a key element in ecosystem functionality and a basic food item for many species. It must be estimated through traditional costly field sampling, normally at just a few sampling points. Arthropod biomass and plant productivity should be narrowly related because a large majority of arthropods are herbivorous, and others depend on these. Quantifying plant productivity with satellite or aerial vehicle imagery is an easy and fast procedure already tested and implemented in agriculture and field ecology. However, the capability of satellite or aerial vehicle imagery for quantifying arthropod biomass and its relationship with plant productivity has been scarcely addressed. Here, we used unmanned aerial vehicle (UAV) and satellite Sentinel-2 (S2) imagery to establish a relationship between plant productivity and arthropod biomass estimated through ground-truth field sampling in shrub steppes. We UAV-sampled seven plots of 47.6-72.3 ha at a 4-cm pixel resolution, subsequently downscaling spatial resolution to 50 cm resolution. In parallel, we used S2 imagery from the same and other dates and locations at 10-m spatial resolution. We related several vegetation indices (VIs) with arthropod biomass (epigeous, coprophagous, and four functional consumer groups: predatory, detritivore, phytophagous, and diverse) estimated at 41-48 sampling stations for UAV flying plots and in 67-79 sampling stations for S2. VIs derived from UAV were consistently and positively related to all arthropod biomass groups. Three out of seven and six out of seven S2-derived VIs were positively related to epigeous and coprophagous arthropod biomass, respectively. The blue normalized difference VI (BNDVI) and enhanced normalized difference VI (ENDVI) showed consistent and positive relationships with arthropod biomass, regardless of the arthropod group or spatial resolution. Our results showed that UAV and S2-VI imagery data may be viable and cost-efficient alternatives for quantifying arthropod biomass at large scales in shrub steppes. The relationship between VI and arthropod biomass is probably habitat-dependent, so future research should address this relationship and include several habitats to validate VIs as proxies of arthropod biomass.

Genetic consequences of interglacial isolation in a steppe bird.

In response to climate changes that have occurred during Pleistocene glacial cycles, taxa associated to steppe vegetation might have followed a pattern of historical evolution in which isolation and fragmentation of populations occurred during the short interglacials and expansion events occurred during the long glacial periods, in contrast to the pattern described for temperate species. Here, we use molecular genetic data to evaluate this idea in a steppe bird with Palaearctic distribution, the little bustard (Tetrax tetrax). Overall, extremely low genetic diversity and differentiation was observed among eight little bustard populations distributed in Spain and France. Mismatch distribution analyses showed that most little bustard populations expanded during cooling periods previous to, and just after, the last interglacial period (127,000-111,000 years before present), when steppe habitats were widespread across Europe. Coalescent-based methods suggested that glacial expansions have resulted in substantial admixture in Western Europe due to the existence of different interglacial refugia. Our results are consistent with a model of evolution and genetic consequences of Pleistocene cycles with low between-population genetic differentiation as a result of short-term isolation periods during interglacials and long-term exchange during glacial periods.

Disentangling the molecular mechanisms of multiple sclerosis: The contribution of twin studies.

Twin studies of disease concordance are useful to weight the relative contribution of genetic and environmental factors to the cause of common complex disorders. In multiple sclerosis (MS) different twinning rates from geographic areas at different prevalence suggested that heritable and non-heritable factors contribute in different proportions and ways to MS risk in diverse populations. This concept prompted genome-wide association studies, and the implementation of the co-twin control design, that allows stringent experimental approaches in MS-discordant identical pairs, controlling for genetic influences and many other known and unknown factors. The co-twin control design provided important clues on MS molecular model. These studies will be reviewed, focusing on those showing significant differences between affected and healthy co-twins. In some cases, differences that emerged in non-twin patients compared to matched controls were not confirmed in identical MS-discordant pairs, suggesting an 'MS subclinical trait'. Early patterns of magnetic resonance imaging and predictive biomarkers that characterize 'healthy' co-twins may be useful for the identification of a prodromal reversible phase of the disease.

Clinical case report and literature review: metachronous colorectal splenic metastases.

A 52-year-old woman with a rising carcinoembryonic antigen CEA, no clinical or radiological findings, a negative colonoscopy, and a positron emission tomography (PET) scan that revealed an isolated hypermetabolic lesion in the spleen. The patient underwent splenectomy by laparoscopic surgery. The pathological study confirmed the presence of an isolated metastasis to the spleen. This case reveals the rare occurrence of isolated splenic metastases in the context of colorectal cancer and illustrates the role of PET when a patient shows a rising CEA with negative clinicoradiological studies.

Intestinal Permeability in Relapsing-Remitting Multiple Sclerosis.

Changes of intestinal permeability (IP) have been extensively investigated in inflammatory bowel diseases (IBD) and celiac disease (CD), underpinned by a known unbalance between microbiota, IP and immune responses in the gut. Recently the influence of IP on brain function has greatly been appreciated. Previous works showed an increased IP that preceded experimental autoimmune encephalomyelitis development and worsened during disease with disruption of TJ. Moreover, studying co-morbidity between Crohn's disease and MS, a report described increased IP in a minority of cases with MS. In a recent work we found that an alteration of IP is a relatively frequent event in relapsing-remitting MS, with a possible genetic influence on the determinants of IP changes (as inferable from data on twins); IP changes included a deficit of the active mechanism of absorption from intestinal lumen. The results led us to hypothesize that gut may contribute to the development of MS, as suggested by another previous work of our group: a population of CD8+CD161high T cells, belonging to the mucosal-associated invariant T (MAIT) cells, a gut- and liver-homing subset, proved to be of relevance for MS pathogenesis. We eventually suggest future lines of research on IP in MS: studies on IP changes in patients under first-line oral drugs may result useful to improve their therapeutic index; correlating IP and microbiota changes, or IP and blood-brain barrier changes may help clarify disease pathogenesis; exploiting the IP data to disclose co-morbidities in MS, especially with CD and IBD, may be important for patient care.

Parotid gland metastasis of a breast cancer.

Parotid gland metastases from malignant tumors are extremely rare. A 61-year-old woman was diagnosed with an early breast cancer with no expression of oestrogen and progesterone receptors. Five years later the patient presented a tumour in parotid gland. After total parotidectomy, microscopic analysis of the gland demonstrated an invasive duct carcinoma (IDC) with positive expression of oestrogen receptor. The patient was treated with chemotherapy followed by complementary local radiotherapy. Diagnosis of a metastasic tumour in parotid gland poses a challenge. In our case an immunohistochemical study of oestrogen receptor was fundamental to establish a diagnosis.

Efficacy of CDP-choline in the treatment of senile alterations in memory.

Alterations in membrane function may occur as a consequence of aging because of a decrease in the synthesis or an increase in the catabolism of choline and ethanolamine glycerophospholipids, leading to impairment in cognitive function. Experimental studies have shown that the administration of CDP-choline increases the total amount of phosphatidylcholine and other related phospholipids in the brain and in some cases may enhance neurotransmission. Clinical assessments and neuropsychologic tests in patients with cerebral insufficiency, chronic cerebrovascular disease, and dementia suggest that CDP-choline may improve some of the memory deficits associated with aging.

Levo-carnitine, its derivatives, and free fatty acids in serum, heart, liver, and muscle of both tumoral and alcoholic rats.

We present a comparative study of carnitine-related fatty acid metabolism in rats bearing a Yoshida sarcoma, in chronic alcoholic rats, and in control rats. Levels of levo-carnitine, acetylcarnitine, acylcarnitine, and free fatty acids were studied in serum and in different tissues--liver, heart, and skeletal muscle--of each group of rats. Chronic alcoholic rats showed high levels of free fatty acids and elevated levo-carnitine and acetylcarnitine levels relative to those of the controls. Biosynthesis of carnitine appeared to be increased, whereas fatty acid oxidation was depressed. Tumor-bearing rats also showed high levels of free fatty acids in both serum and tissues. However, levels of levo-carnitine were decreased in this group. It seems that the tumor not only utilizes the precursors of carnitine biosynthesis but also increases carnitine expenditure.

2,3-Diphosphoglycerate, a cellular ageing metabolite.

The concentration of 2,3-diphosphoglycerate was increased in whole venous blood of patients with various cancers, including those of breast, ovary, lung and colon, but not rectum, compared with age-matched controls. Higher values, increasing with age, were also found in patients with Hodgkin's disease and other lymphomas. This abnormality is considered to be due to increased synthesis of the metabolite by the tumour tissue.

Total anomalous left pulmonary venous connection with intact atrial septum: surgical treatment of a rare case.

Total anomalous left pulmonary venous connection with intact atrial septum is an extremely rare form of congenital heart disease. We describe a case never reported before in which the left pulmonary veins drained directly into the right atrium through a common vein. Surgical correction was successfully obtained by redirecting the blood flow through a newly created atrial septal defect into the left atrium using a gluteraldehyde-treated autologous pericardial patch. Follow-up at 6 months shows no signs of any complication.

A comparative study of magnetic resonance cholangiography and direct cholangiography.

OBJECTIVE: Magnetic resonance cholangiopancreatography (MRCP) is a rapidly developing method for the noninvasive assessment of the biliary tree and pancreatic duct that obviates the need for contrast medium. We describe our experience with this new diagnostic imaging method in patients with obstruction of the biliary tree. We assessed both the location and cause of obstruction, and compared the results with direct cholangiography. METHODS: Between 1997 and 1998, 81 patients underwent MRCP at our facility. Two different image acquisition protocols (half-Fourier acquisition single-shot turbo spin-echo -HASTE- and rapid acquisition with relaxation enhancement -RARE-) for T2-weighted turbo spin echo sequences as well as cross-sectional fast multiplanar gradient-echo pulse (T1-weighted FL2D) and T2-weighted fast spin echo (T2 TSE) sequences were used. All patients underwent direct (either percutaneous or endoscopic retrograde) cholangiography or surgery for confirmation and/or treatment. The images obtained with MRCP were evaluated by two radiologists with expertise in biliary tree imaging who were unaware of the patient's clinical characteristics, and their diagnostic interpretations were compared with the findings obtained upon surgery or direct cholangiography. RESULTS: The sensitivity and specificity of MRCP in ruling out pathologies and detecting the presence of dilatation of the biliary tree were 100%. In assessing the level of the obstruction, sensitivity and specificity varied with location (intrahepatic/hilar, suprapancreatic, intrapancreatic or ampullary). Sensitivity in these locations was 100, 92, 69 and 86%, respectively, whereas specificity was 100, 94, 92 and 91%, respectively. In determining the cause of the obstruction, the results were variable depending on the cause: choledocholithiasis (sensitivity, 89%; specificity, 90%) malignant obstruction (sensitivity, 92%; specificity, 88%), benign stricture (sensitivity, 63%; specificity, 90%), and chronic pancreatitis (sensitivity, 50%; specificity, 99%). CONCLUSIONS: MRCP offered high diagnostic accuracy in the assessment of the occurrence and location of biliary obstruction. Sensitivity and specificity in establishing the cause varied, and were highest for choledocholithiasis and malignant obstruction. MRCP may be used instead of ERCP, which may then be reserved for patients who are likely to require surgery.

[Self-training in needle-knife sphincterotomy]. / Aprendizaje no tutelado de la esfinterotomía de aguja.

AIM: To analyze our experience in self-training in needle-knife sphincterotomy and to estimate the number of procedures necessary to reach competence in this technique. METHOD: Retrospective analysis of the first 60 needle-knife sphincterotomies performed, paying attention to success rates, the need for one or two attempts and the incidence and severity of early complications. The results were analyzed and divided into 2-year periods. The training period was subsequently determined using a qualitative method which combines the three above-mentioned criteria and sets competence level at 90%. RESULTS: Of the 60 attempted needle-knife sphincterotomies (five in Billroth-II patients), 54 (90%) were completed. The procedure was required in 20% of all the sphincterotomies completed. Needle-knife sphincterotomy was completed at the first attempt in 39 (65%) patients and complications appeared in 13 (22%), three (5%) of which were serious but not fatal. Analysis of 2 year periods showed an almost 100% increase in the total number of needle-knife sphincterotomies completed and in those completed at the first attempt, as well as a reduction in the complication rate, which subsequently stabilized at below 15%. Forty needle-knife sphincterotomies were needed to reach competence level. CONCLUSION: Needle-knife sphincterotomy can be learned without training from an endoscopist with experience in this technique. Competence can be reached after 40 procedures. Nevertheless, we propose an alternative method to our own to achieve competence in less time and with fewer complications.

[Transitional carcinoma of the ureter and ipsilateral synchronous renal cell carcinoma in hydronephrotic atrophic kidney: infrequent association]. / Carcinoma transicional de uréter y carcinoma ipsilateral sincrónico de células renales en riñón atrófico hidronefrótico: asociación infrecuente.

We report a new case of simultaneous occurrence of renal cell carcinoma and transitional cell carcinoma into ipsilateral ureter. A review of the literature to date indicates this is the 45 world-wide case and the 8 in the Spanish publications.

Increased susceptibility of carbamylated glutamate dehydrogenase to proteolysis.

Glutamate dehydrogenase is very susceptible to carbamylation which results in loss of activity. The effect of a number of proteolytic enzymes (pronase, trypsin and chymotrypsin) on native and carbamylated glutamate dehydrogenase was tested. In all cases, the carbamylated enzyme was at least twice as susceptible to proteolysis as the native enzyme. Antibodies were prepared against glutamate dehydrogenase and carbamylated glutamate dehydrogenase; the carbamylated enzyme was antigenically indistinguishable from the native enzyme. Preliminary experiments indicate that the carbamylated glutamate dehydrogenase is taken up by ascites tumor cells while glutamate dehydrogenase is not. It seems possible that the effects described can be extrapolated to degradation by lysosomes and to other covalently modified enzymes.

[Development of methods for the qualitative and quantitative determination of urinary glucose]. / Entwicklungsstand der qualitativen und quantitativen Bestimmungen der Harnglukose.

The methods for proof and determination of urinary glucose practiced in the GDR are discussed and in a comparative determination confronted to the hexokinase method (Glucoquant). Apart from this the Biophan-G stripe was compared with the multi-test stripes Ecur-test (Boehringer) and N-multistix (Ames). The methods of urinary glucose which are declared as obligatory for the GDR in the DAB 7 (D. L.) do no more correspond to the present level of knowledge. The Biophan-G stripe is the exception. By means of Ecur-test and N-multistix an in every case a 98 per cent correct semiquantitative evaluation was obtained in 250 different urines, in the Biophan-G stripe a 94 per cent evaluation.