Dietary preferences of brachyuran crabs from Taiwan for marine or terrestrial food sources: evidence based on fatty acid trophic markers

BACKGROUND

Trophic interactions are key processes, which determine the ecological function and performance of organisms. Many decapod crustaceans feed on plant material as a source for essential nutrients, e.g. polyunsaturated fatty acids. Strictly herbivorous feeding appears only occasionally in marine decapods but is common in land crabs. To verify food preferences and to establish trophic markers, we studied the lipid and fatty acid composition of the midgut glands of two marine crab species (Grapsus albolineatus and Percnon affine), one semi-terrestrial species (Orisarma intermedium, formerly Sesarmops intermedius), and one terrestrial species (Geothelphusa albogilva) from Taiwan.

RESULTS

All species showed a wide span of total lipid levels ranging from 4 to 42% of the dry mass (%_DM) in the marine P. affine and from 3 to 25%_DM in the terrestrial G. albogilva. Triacylglycerols (TAG) were the major storage lipid compound. The fatty acids 16:0, 18:1(n-9), and 20:4(n-6) prevailed in all species. Essential fatty acids such as 20:4(n-6) originated from the diet. Terrestrial species also showed relatively high amounts of 18:2(n-6), which is a trophic marker for vascular plants. The fatty acid compositions of the four species allow to clearly distinguish between marine and terrestrial herbivorous feeding due to significantly different amounts of 16:0, 18:1(n-9), and 18:2(n-6).

CONCLUSIONS

Based on the fatty acid composition, marine/terrestrial herbivory indices were defined and compared with regard to their resolution and differentiating capacity. These indices can help to reveal trophic preferences of unexplored species, particularly in habitats of border regions like mangrove intertidal flats and estuaries.

Pathways to self-organization: Crystallization via nucleation and growth

Crystallization, a prototypical self-organization process during which a disordered state spontaneously transforms into a crystal characterized by a regular arrangement of its building blocks, usually proceeds by nucleation and growth. In the initial stages of the transformation, a localized nucleus of the new phase forms in the old one due to a random fluctuation. Most of these nuclei disappear after a short time, but rarely a crystalline embryo may reach a critical size after which further growth becomes thermodynamically favorable and the entire system is converted into the new phase. In this article, we will discuss several theoretical concepts and computational methods to study crystallization. More specifically, we will address the rare event problem arising in the simulation of nucleation processes and explain how to calculate nucleation rates accurately. Particular attention is directed towards discussing statistical tools to analyze crystallization trajectories and identify the transition mechanism.

Dynamical phases of attractive particles sliding on a structured surface

Inspired by experiments on quartz crystal microbalance setups, we study the mobility of a monolayer of Lennard-Jones particles driven over a hexagonal external potential. We pay special attention to the changes in the dynamical phases that arise when the lattice constant of the external substrate potential and the Lennard-Jones interaction are mismatched. We find that if the average particle separation is such that the particles repel each other, or interact harmonically, the qualitative behavior of the system is akin to that of a monolayer of purely repulsive Yukawa particles. On the other hand, if the particles typically attract each other, the ensuing dynamical states are determined entirely by the relative strength of the Lennard-Jones interaction with respect to that of the external potential.

Spectrum of viral infections in patients with cystic fibrosis

This review explores the extensive influence of viral infections leading to chronic deterioration of lung function in patients with cystic fibrosis (CF). The mechanisms how viral agents affect the pathogenesis as well as the inflammatory and immune response of CF are discussed. Viral infections of the upper and lower respiratory tract due to viruses in CF patients and methods for diagnosis of respiratory viruses are described in detail. The importance of respiratory and non-respiratory viral agents for the pathogenesis, especially for the exacerbation of bacterial lower respiratory tract infections and course of CF, is stressed, especially emphasizing respiratory syncytial virus, influenza virus, rhinovirus, and human herpes viruses. Possible harmful effects of further viruses like adenovirus, bocavirus, coronavirus, metapneumovirus, parainfluenzavirus on the lung function of CF patients are discussed. The potential use of adenovirus-based vectors for somatic gene therapy is mentioned.

The influence of virus infections on the course of COPD

Chronic obstructive pulmonary disease (COPD) is extensively influenced by viral infections. The mechanisms of how viral agents affect the pathogenesis and prognosis of COPD are numerous. In general, patients with infectious exacerbations are characterized by longer hospitalization periods and greater impairment of several lung function parameters than those with non-infectious exacerbations. Prodromal, clinical, and outcome parameters fail to distinguish virally from non-virally induced illnesses in cases of exacerbations. The importance of infections with respiratory and non-respiratory viral agents for pathogenesis and course of COPD is detailed. Human adenovirus, non-respiratory viruses including human immunodeficiency virus, human metapneumovirus, influenza virus, human rhinovirus, and respiratory syncytial virus are especially stressed.

Indications and limitations of endoscopic ultrasound elastography for evaluation of focal pancreatic lesions

BACKGROUND AND STUDY AIM

Endoscopic-ultrasound-guided elastography (EUS-elastography) is a recently introduced imaging procedure that distinguishes tissues on the basis of their specific consistency. The aim of this prospective study was to investigate the role of this new technique in the characterization and differentiation of focal pancreatic lesions.

PATIENTS AND METHODS

This prospective study enrolled 70 patients with unclassified solid lesions of the pancreas and 10 controls with a healthy pancreas. In all patients elastography recordings were compared with cytology/histology findings as the gold standard.

RESULTS

Adequate EUS-elastography of the pancreas was performed in all healthy controls but in only 56 % of patients with solid pancreatic lesions. The main limitation of elastographic image acquisition was incomplete delineation of the border of lesions greater than 35 mm in diameter (39 %) or of lesions at some distance from the transducer (10 %). Elastographic recordings were also hampered by the fact that the surrounding tissue, which is used as an internal reference standard for strain calculation, was insufficiently displayed in the case of larger lesions. The reduced ratio of target to surrounding tissue resulted in the formation of color artifacts and in impaired reproducibility. In contrast, the majority of lesions smaller than 35 mm in diameter were adequately and reproducibly evaluated by EUS-elastography (91 %). The clinical use for differential diagnosis, however, seems limited, since strain images from all kinds of pancreatic masses were found to be harder than the surrounding tissues, irrespective of the underlying nature of the lesion (i. e., malignant vs. benign). EUS-elastography predicted the nature of pancreatic lesions with poor diagnostic sensitivity (41 %), specificity (53 %), and accuracy (45 %).

CONCLUSION

EUS-elastography of the pancreas has the potential to obtain some complementary information that would improve tissue characterization. Its clinical utility, however, remains questionable, and it seems unlikely that the information provided will obviate the necessity of obtaining tissue samples for confirmation of a final pathologic diagnosis.

Oxygen generation by combined electrolysis and fuel-cell technology: clinical use in COPD patients requiring long time oxygen therapy

BACKGROUND

Oxy-Gen lite, a recently developed combined electrolysis and fuel cell technology, de-novo generates oxygen with high purity for medical use from distilled water and room air. However, its use in patients with chronic respiratory failure has never been evaluated.

OBJECTIVES

To test the clinical applicability and safety of Oxy-Gen lite technology, we enrolled 32 COPD patients with chronic hypoxemia and long-term oxygen therapy (LTOT) in a controlled, randomized, multicenter clinical trial.

MATERIALS AND METHODS

Standard continuous oxygen therapy with a maximal flow rate of 2 L/min was tested against pulsatile oxygen delivery by Oxy-Gen lite. Oxygen saturation at seated-rest was recorded over 30 min and used as a primary read-out parameter. Oxygen saturation was also recorded during mild physical strain (speaking out loud) or overnight's sleep.

RESULTS

Both methods of oxygen supply established oxygen saturations within the normal range (i.e., upper plateau of the sigmoid oxyhaemoglobin dissociation curve) compared to breathing room air (p<0.0001). Mean oxygen saturation under standard continuous oxygen flow or Oxy-Gen lite technology during rest, physical strain or sleep proved statistically equivalent (95%CI<2.5% of reference saturation).

CONCLUSION

The use of Oxy-Gen lite in COPD patients with hypoxemia and LTOT <or= 2 L/min is safe and results in oxygen saturation comparable to standard oxygen therapy. There is evidence that this form of oxygen supply is not only functional during rest but also during mild physical strain or overnight's sleep. Low noise, energy- and overhead-costs are particular advantages of this technology.

[Retroperitoneal bronchogenic cyst]

We describe a 35-year-old female patient who underwent surgery because of a coincidentally occurring cryptic tumour near the left adrenal gland and a right renal carcinoma (pT1, N0, G2, R0). The left-sided tumour was intraoperatively identified as a cystic structure filled with secretion. Histopathological analysis provided the diagnosis of a bronchogenic cyst.

Depletion-induced percolation in networks of nanorods

Above a certain density threshold, suspensions of rodlike colloidal particles form system-spanning networks. Using Monte Carlo simulations, we investigate how the depletion forces caused by spherical particles affect these networks in isotropic suspensions of rods. Although the depletion forces are strongly anisotropic and favor alignment of the rods, the percolation threshold of the rods decreases significantly. The relative size of the effect increases with the aspect ratio of the rods. The structural changes induced in the suspension by the depletant are characterized in detail and the system is compared to an ideal fluid of freely interpenetrable rods.

Verbesserung des exspiratorischen Spitzenflusses (PEF) von COPD-Patienten durch Lungensport über 12 Monate

This prospective, randomised, controlled study deals with the question whether it is possible to induce an improvement of peak expiratory flow (PEF) in patients suffering from COPD by a structured "lung" sport programme over a longer period of time (12 months). Furthermore, a comparison with the spontaneous course of the disease was performed. A group of 7 COPD patients (1 man, 6 women, mean age 70 years, COPD grade II - III according to GOLD) who regularly took part in a structured lung sport programme was compared with a control group of 10 COPD patients (5 men, 5 women, mean age 67.5 years, COPD grade II - III according to GOLD) who denied doing sport. The PEF values of the patients were measured after 0 and 12 months during exacerbation-free intervals. The relative changes of PEF in percent after one year were statistically compared. There was an improvement of PEF of about + 10.4 % (standard deviation SD +/- 8.9 %) after 12 months of lung sport. The spontaneous course of the disease of the patients who denied doing sport led to a decrease of PEF of about - 8.8 % (standard deviation SD +/- 11.5 %). The difference in PEF changes with respect to "lung" sport and to the spontaneous course of COPD was highly significant (p < 0.01) in spite of a high standard deviation. The long lasting improvement of PEF due to sport among COPD patients speaks in favour of a positive effect of "lung" sport.

[Ureteral rupture when changing a suprapubic vesical catheter]

We describe, for the first time, a rupture of the ureter caused by changing a suprapubic vesical catheter. The guide wire passed into the ostium of the left ureter during the procedure, and the catheter was pushed over the wire into the left ureter blocking it. The lesion was diagnosed by intravenous pyelography. A pigtail stent was placed in the left ureter.

Darmtuberkulose als Hauptmanifestation einer systemischen Tuberkulose

We describe a rare case of tuberculosis with mainly gastrointestinal problems. The 52-year-aged female patient came to hospital with unclear pain in the lower abdomen and ascites that was refractory to therapy. The computed tomography of the thorax showed right-sided confluating lymphoid nodes, the CT of the abdomen showed ascites and nodular structures near the coecum. Tissue samples were taken from the mucosa of the colon, the inflammatory altered peritoneum, the left bronchus of the upper lobe and the confluating lymphoid nodes in the mediastinum during colonoscopy, diagnostic laparoscopy and bronchoscopy. The samples from the peritoneum showed granulomas with caseating necroses in histological slices. Mycobacterium tuberculosis was detected by PCR in the tissue samples from the lymphoid tissue of the mediastinum. Furthermore, Mycobacterium tuberculosis grew in cultures from samples of the abdominal ascites. The symptoms and pathological findings improved under a therapy comprising isoniazid, rifampicin, ethambutol and pyrazinamid.

[Post-operative sclerosing mesenteritis]

For the first time we describe a sclerosing mesenteritis that appeared acutely after abdominal operations. The patient suffered from diffuse abdominal symptoms. There was a hard tumour in the left middle and lower abdomen. Histological analysis revealed fibrosis and bone tissue. Symptoms improved after application of prednisone and high-calorie infusions.

[Villous adenoma of the renal pelvis and ureter]

Villous adenomas of the urinary tract are extremely rare tumours belonging to the adenoepithelial metaplasias. They can be associated with other neoplasias, especially with carcinomas. We describe the case of an 85-year-old female patient suffering from a villous adenoma of the renal pelvis and ureter.

Assessment of body composition of patients with COPD

The intention of the study was to determine nutritional state and body cell mass in patients with COPD in comparison with healthy volunteers between 50 and 75 years of age. Therefore, body cell mass (BCM), phase angle and the relation between extra cellular mass and body cell mass ECM/BCM was measured with the help of bioelectrical impedance analysis (BIA). While 10.4 % of COPD patients (male 5.0 %, female 18.8 %) had a BMI of < 18.5, no subject was underweight in the healthy volunteers. Overweight was found in 31.7 % patients (male 36.0 %, female 25.0 %) and in 54.2 % healthy subjects (male: 62.5 %, female 46.9 %), 17.1 % of our patients (male 16.0 %, female 18.8 %) versus 21.7 % of healthy subjects (male 14.3 %, female 28.1 %) were obese. While there was no statistic significance for a lower BMI in COPD patients, there were significantly decreased values concerning muscle mass -- represented by BCM-values -- and state of nutrition -- represented by BCM, phase angle and ECM/BCM values -- in COPD patients compared with healthy volunteers. These results suggest that BMI alone doesn't allow conclusions regarding to nutritional state and physical training. A malnutrition requiring intervention might exist in spite of a normal or even high BMI in COPD patients.

Peak expiratory flow as a predictor for the effectiveness of sport for patients with COPD

This study intended to find simple parameters that were able to determine the increase in physical performance as a result of sport in a group of patients with COPD (lung sport). We regularly investigated pulse, oxygenation and peak expiratory flow in participants with COPD of a "lung sport group", who participated in a structured weekly training program under professional supervision. Ten volunteers (7 females, 3 males, median of age = 69) with COPD (grade II-III) took part in the study. - The relative changes after 3 and 6 months were compared with the values of the first month of exercise. Measurements were carried out before exercise, after stamina training and at the end of the program. - Pulse and oxygenation did not show any changes. However, there was a significant improvement of peak flow after 6 months. - These peak flow changes represent further evidence of positive effects of sport in COPD and provide a parameter which allows the patients themselves to measure and evaluate the success of their physical activity.

[Pneumonia induced by nocardia -- a case report]

We describe a case of lung manifestation of nocardiosis with upper lobe shrinking of the right lung in a 45 year old patient without evident signs of an immuno-compromising illness. The patient came to the hospital in a reduced general state of health with severe cough, red and brown sputum and exertional dyspnoea. X-ray pictures of the thorax showed inflammatory infiltration and shrinking of the upper left lobe of the right lung. Gram-positive, branching rods were detected in the patient's bronchial secretion with the microscope and in cultures. Nocoardia transvalensis was identified via polymerase chain reaction (PCR). The antibiotic therapy was planned according to the bacterial resistance pattern. Imipenem was administered for 5 weeks and Amikacin was added for 3 weeks in the 3 (rd) week of therapy. The patient left the hospital in a good general state of health. There was no relapse.

[Tuberculosis induced by Bacillus Calmette-Guerin immuno-prophylaxis -- case study]

We describe a case of miliary tuberculosis induced by Bacillus Calmette-Guerin (BCG) as a complication of an infection after BCG-instillation therapy into the bladder because of bladder carcinoma. Bacilli surely entered blood circulation via an urethral lesion because of a difficult catheterisation. The 60 year old patient was administered to the hospital with septic temperature 4 four days after BCG instillation. CT showed a miliary patten and the diagnosis was confirmed by bronchoscopy: transbronchial biopsy showed granulomatous infiltration and an acid-fast rod-bacterium was detected in bronchial slime. Symptoms vanished after a consequent antituberculous triple therapy regime and the patient left hospital in a good general state of health.