Assessing landscape health by scaling with remote sensing: when is it not enough?

Assessment of the health of landscapes, by monitoring their condition over space and time, is needed to better understand the processes for sustaining or, in many cases, repairing them. Remote sensing is a tool that can efficiently identify and assess areas of landscape damage at different scales and help land managers solve specific problems. Remote sensing may appear to be a panacea for all monitoring situations but sometimes the information it provides is not enough by itself. In this paper we give examples of both scenarios—when remote sensing alone is adequate and when it is not. When remotely sensed data alone is not sufficient, monitoring problems can be solved by incorporating additional finer scale data. We use a five-step procedure based on scaling to help land managers answer the question: when is remote sensing data alone not sufficient to underpin the information needs required to achieve a specific management goal?     

Meat juice ELISA for determination of Salmonella incidence in slaughter pig herds in Bavaria

Meat samples from diaphragm pillars were randomly taken from 3,048 pigs of 52 Bavarian herds after slaughtery. Meat-juice was collected and tested for salmonella antibodies in an indirect ELISA. The number of samples was calculated according to the annual production of slaughter pigs of a farm outlined in the "Leitlinien für ein Programm zur Reduzierung des Eintrags von Salmonellen durch Schlachtschweine in die Fleischgewinnung" from February 05th, 1998 (< 100 slaughter pigs: 45 samples, 100-200 slaughter pigs: 50 samples, > 200 slaughter pigs: 60 samples per year). Salmonella antibodies were detected in 48 carcasses (1.6%) of 12 farms (23.1%). However, 33 (68.8%) of these carcasses were originated from a single farm which had to be classified into category III (prevalence of > 40% in the samples). No bacteria could be isolated from this farm in a follow up examination. The 51 other farms (98%) were classified into category I (prevalence of < 20% in the samples). Farms with in/out-management showed a higher degree of reagents (2.1T%) than farms with continuous stabling (0.8T%). In a pig experimentally immunized with LPS-antigen preparations of Salmonella typhimurium it was shown that antibodies induced were nearly at the same level in all meat samples and even in selected organs (liver, kidney, parotis, mesenteric lymph nodes).     

Use of closed-suction drains to treat generalized peritonitis in dogs and cats: 40 cases (1997-1999)

OBJECTIVE: To determine outcome of dogs and cats with generalized peritonitis treated by means of closed-suction drainage. DESIGN: Retrospective study. ANIMALS: 30 dogs and 10 cats with generalized peritonitis. PROCEDURE: Medical records were reviewed, and information on signalment, clinicopathologic abnormalities, contamination source, results of microbial culture, surgical procedure performed, postoperative management, complications, and outcome was obtained. RESULTS: The gastrointestinal tract was the most common source of contamination. Abdominal fluid collected from 34 patients at the time of surgery was submitted for bacterial culture; results were positive for 28 (82%). The most commonly isolated organism was Escherichia coli. Postoperative complications included anemia (n = 21), hypoproteinemia (21), vomiting (9), edema (7), and diarrhea (5). Total solids concentration did not decrease during the first 48 hours after surgery, and all drains remained functional until removal. Twenty-eight patients survived to the time of discharge; 8 of the 12 animals that died did so within 18 hours after surgery. The only factor significantly different between patients that survived and patients that died was postoperative systolic blood pressure. Factors that were not significantly associated with outcome included detection of bacteria in the abdominal fluid, number of organisms cultured from the abdominal fluid, selection of antimicrobials for empiric treatment, and source of contamination. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that closed-suction drainage may be a useful method for treating generalized peritonitis in dogs and cats. No clinically important complications were associated with their use.     

The structure of a complex of recombinant hirudin and human alpha-thrombin

The crystallographic structure of a recombinant hirudin-thrombin complex has been solved at 2.3 angstrom (A) resolution. Hirudin consists of an NH2-terminal globular domain and a long (39 A) COOH-terminal extended domain. Residues Ile1 to Tyr3 of hirudin form a parallel beta-strand with Ser214 to Glu217 of thrombin with the nitrogen atom of Ile1 making a hydrogen bond with Ser195 O gamma atom of the catalytic site, but the specificity pocket of thrombin is not involved in the interaction. The COOH-terminal segment makes numerous electrostatic interactions with an anion-binding exosite of thrombin, whereas the last five residues are in a helical loop that forms many hydrophobic contacts. In all, 27 of the 65 residues of hirudin have contacts less than 4.0 A with thrombin (10 ion pairs and 23 hydrogen bonds). Such abundant interactions may account for the high affinity and specificity of hirudin.     

Expression of the multidrug-resistant gene in hepatocarcinogenesis and regenerating rat liver

Preneoplastic and neoplastic liver nodules and hepatocytes isolated from regenerating rat liver have been shown to be resistant to a broad range of carcinogenic agents. This phenomenon was studied by measuring the expression of the multidrug-resistant (mdr) gene in normal liver cells and in preneoplastic and neoplastic nodules and regenerating liver. Levels of messenger RNA for the mdr gene, which encodes P-glycoprotein, were elevated in both preneoplastic and neoplastic lesions. Expression of the mdr gene also reached high levels in regenerating rat liver 24 to 72 hours after partial hepatectomy. These results show that the expression of the mdr gene can be regulated in liver and is likely to be responsible for part of the multidrug-resistance phenotype of carcinogen-initiated hepatocytes and regenerating liver cells.     

New data regarding distribution of cattle ticks in the south-western Indian Ocean islands

Recent studies have produced new insight into the origin and distribution of some cattle ticks in the south-western Indian Ocean islands. Rhipicephalus appendiculatus, introduced from Tanzania in 2002, is now well established on Grande Comore but has not yet reached the other islands of the archipelago (Mohéli, Anjouan and Mayotte). Only one of the two clades identified in Africa has settled so far. Amblyomma variegatum, which was not supposed to be able to persist in the Antananarivo region (1300 m) nor in other Malagasy regions of high altitude without regular introductions of ticks by infested cattle, is now endemic as a general rule up to 1600 m although other regions of lower altitude (1400 m) are still free of the tick. This species remains confined in a small area of the west coast on La Reunion Island. On the contrary, Hyalomma dromedarii could not settle on Madagascar where it was introduced in 2008 and Rhipicephalus evertsi evertsi is not yet present in Grande Comore despite regular introductions by infested cattle from Tanzania. A phylogeographic approach has been carried out at an intra-specific level for A. variegatum. This study has led to the identification of two main lineages, one covering all species distribution and one restricted to East Africa and the Indian Ocean area. These two lineages are in sympatry in Madagascar where a high genetic diversity has been described, whereas a lower genetic diversity is observed on other islands. These results seem to agree with the historical data concerning the introduction of the tick in the Indian Ocean area.