Image Transfer by Mobile Phones in Neurosurgery

Image transfer by mobile phones with built-in cameras (1 Megapixel CCD digital camera, 7 stage digital zoom, max. picture size 858 x 1 144 pixels, display resolution 240 x 320 dots, 262 K colour system CGS LCD) was introduced into clinical practice in the author's department in July 2004 to improve communication between neurosurgeons. During the first 12 months of use 13-72 images per month with an average of 1.4 images/case were transmitted via the regular German mobile phone net (GRPS standard, 40 KBit/s) among all neurosurgeons. Most images were transferred from the resident on call to the senior neurosurgeon backing him up. Overall, the system was extremely reliable, quick, and enabled immediate decisions in all emergency situations. In conclusion, image transfer by mobile phones has significantly improved communication within our department.

General versus locoregional anesthesia in carotid surgery: A prospective randomised trial

Background: To evaluate the influence of anesthetic technique on perioperative neurological and cardiopulmonary complication rates in patients undergoing carotid endarterectomy. Patients and methods: 186 patients with symptomatic internal carotid artery (ICA) stenosis > 70% or asymptomatic ICA stenosis > 80% were prospectively randomized for either locoregional (LA) or general anesthesia (GA). Results: Neurological complication rates were similar in both groups (GA 2% vs. LA 2%). Cardiopulmonary complication rates were not significantly different (GA 4% vs LA 1%).There were no stroke-related deaths, but one patient from the GA group died from severe postoperative pneumonia. Thus, a significant difference in combined stroke / cardiopulmonary related death between the two groups (GA 1% vs LA 0%) could not be found. However, perioperative cardiopulmonary monitoring showed that significantly more patients operated under general anesthesia had hypertensive events, with systolic blood pressure values greater than 180 mmHg on postoperative day one. There were no differences in the number of postoperatively hypotensive episodes (systolic blood pressure values < 100 mmHg) between the two groups. Conclusions: Significant differences in the perioperative neurological and cardiopulmonary complication rates between general and locoregional anesthesia in patients undergoing carotid endarterectomy could not be observed.

Extended flexible sigmoidoscopy performed by colonoscopists for colorectal cancer screening: a pilot study

BACKGROUND

Caecal intubation can be achieved by extended flexible sigmoidoscopy in 32% of patients.

AIM

To assess the feasibility of extended flexible sigmoidoscopy performed by colonoscopists for colorectal cancer screening.

METHODS

We enrolled 41 patients referred for screening flexible sigmoidoscopy. After purging, examination was performed with a colonoscope. All patients completed sigmoidoscopy (success in meeting referral goal); 93% and 71% had examination to the transverse or ascending colon, and caecum, respectively. Overall yield and right-sided polyps was 56% and 27%, respectively. Caecal intubation and complete examination with polypectomy took 6.0 +/- 2.5 and 18.3 +/- 5.1 min, respectively; with no complications. Twelve patients requested colonoscope withdrawal because of discomfort. Although 46% reported moderate to severe discomfort, 39% and 36%, respectively, were definitely or probably willing to repeat flexible sigmoidoscopy.

RESULTS

Unsedated colonoscopy introduced as extended flexible sigmoidoscopy emphasizes the benefits of added yield rather than the negative image of withholding of discomfort relief. The patient can choose to accept the equivalent of an unsedated colonoscopy or reject the option based on perceived discomfort during extended flexible sigmoidoscopy performed by the colonoscopist.

CONCLUSION

Extended flexible sigmoidoscopy is a feasible option in carefully selected patients, fully prepared and by an experienced colonoscopist.

Inhibition of 7,8-diaminopelargonic acid aminotransferase by amiclenomycin and analogues

Cis and trans stereoisomers of amiclenomycin, a natural L-amino acid antibiotic, have been prepared using unequivocal routes. By using 1H NMR spectroscopy, the configuration of the six-membered ring of natural amiclenomycin was shown to be cis and not trans as originally proposed. Amiclenomycin and some synthetic analogues with the cis configuration irreversibly inactivate DAPA AT (7,8-diaminopelargonic acid aminotransferase), an enzyme involved in biotin biosynthesis, by forming an aromatic PLP (pyridoxal-5'-phosphate)-inhibitor adduct that is tightly bound to the active site. The following kinetic parameters for the inactivation of Escherichia coli DAPA AT by amiclenomycin were derived: K(I)=2 microM and k(inact)=0.4 min(-1). The structure of the aromatic adduct formed upon inactivation was confirmed by UV-visible spectroscopy, X-ray crystal structure determination and MS. Because Mycobacterium tuberculosis DAPA AT is a potential drug target, this enzyme was cloned, overexpressed and purified to homogeneity for biochemical characterization.

Studies on thiamine diphosphate-dependent enzymes

The 3-deaza analogue of TPP (thiamine diphosphate), a close mimic of the ylid intermediate, has been synthesized and is an extremely potent inhibitor of a variety of TPP-dependent enzymes, binding much more tightly than TPP itself. Results using deazaTPP complexed with the E1 subunit of PDH (pyruvate dehydrogenase) have led to a novel proposal about the mechanism of this enzyme. The 2-substituted forms of deazaTPP, which mimic other intermediates in the catalytic mechanism, can also be synthesized and 2-(1-hydroxyethyl)deazaTPP is also an extremely potent inhibitor of PDC (pyruvate decarboxylase). Attachment of such 2-substituents is expected to be a way to introduce selectivity in the inhibition of various TPP-dependent enzymes.

Emotional labour and stress within mental health nursing

For many within the nursing profession, the work role involves a great deal of emotional work or 'emotional labour'. Such emotional work can be performed through 'surface acting' in which the individual simply feigns an appropriate emotion, or through 'deep acting' in which they actually try to feel the required emotion. The current study aims to aid understanding of the complex relationship between components of emotional labour and stress within the mental health nursing sector. Thirty-five mental health nurses completed questionnaires relating to a total of 122 nurse-patient interactions. Data were collected in relation to: (1) the duration and intensity of the interaction; (2) the variety of emotions expressed; (3) the degree of surface or deep acting the nurse performed; and (4) the perceived level of stress the interaction involved. Nurses also completed Daily Stress Indicators. Results suggest that: (1) emotional labour is positively correlated with both 'interaction stress' and daily stress levels; (2) the deeper the intensity of interactions and the more variety of emotions experienced, the more emotional labour was reported; and (3) surface acting was a more important predictor of emotional labour than deep acting. Implications for mental health nurses are outlined.

Identification of Chicken Transmembrane Channel-like (TMC) genes: Expression analysis in the cochlea

Mutations of the human gene encoding transmembrane channel-like protein (TMC)1 cause dominant and recessive nonsyndromic hearing disorders, suggesting that this protein plays an important role in the inner ear. In this study, we cloned chicken Tmc2 (GgTmc2) from a cochlear cDNA library and we annotated four additional TMC family members: GgTmc1, GgTmc3, GgTmc6, and GgTmc7. All chicken TMCs possess the defining TMC signature motif and display high conservation of their genomic structure when compared with other vertebrate TMC genes. GgTmc1 is localized on the chicken sex chromosome Z at a locus that displays conserved synteny with the loci of mammalian orthologues residing on autosomes. In contrast, the locus of GgTmc2 does not exhibit conserved synteny with its mammalian orthologues. Because murine TMC1 and TMC2 are restrictively expressed in cochlear hair cells, we determined the expression of the chicken orthologues in the basilar papilla, the avian equivalent of the organ of Corti. While GgTmc2 was present throughout the basilar papilla and in other tissues, GgTmc1 transcript was detected specifically in the basal portion of the basilar papilla and was not detectable in any other tissue or organ studied. GgTmc3 and GgTmc6 were detectable in all organs analyzed. Antibody labeling revealed that GgTmc2 is predominantly associated with the lateral membranes of hair and supporting cells. The expression of GgTmc2 by both cell types was further confirmed by RT-PCR using isolated cells. This expression and subcellular localization of GgTmc2 is in agreement with the proposed potential role of this novel class of transmembrane proteins in ion transport.

Seltene pulmonale Manifestation eines intrakraniellen meningothelialen Meningeoms

HISTORY AND CLINICAL FINDINGS

A 53-year-old sailor was admitted to our department with the history of severe headache, dysphasia and mild psychotic behavior. Routine chest X-rays several weeks before had shown a focal lung lesion in the lower lobe of the right lung. The patient was without pulmonary symptoms.

INVESTIGATIONS

Brain magnetic resonance imaging demonstrated a large intracranial extracerebral mass with perifocal brain edema in the right frontoparietal region.

THERAPY

The patient was suspected of having a metastasis of an unknown primary tumor. Craniotomy and total removal of the tumor was performed. Histological examination revealed a meningothelial meningioma without signs of malignancy. 6 weeks later thoracotomy and total removal of the lung tumor were performed. Histological examination revealed a meningioma with the same histological pattern as the intracranial lesion. Postoperatively there were no complications, the physical examination at discharge was normal without any pulmonary or neurological deficits. Two years later, we found no evidence of an intracranial or pulmonary tumor recurrence.

CONCLUSION

Pulmonary metastases of benign intracranial meningiomas are rare but should be considered in the differential diagnosis, especially in cases with an undiscovered primary tumor.

Developing clinically relevant and reproducible symptom-defined populations for cancer diagnostic research in general practice using a community survey

BACKGROUND

In developing cancer diagnostic studies, there is a particular need for the population of patients with symptoms of possible oncological significance who consult the GP in 'real life' to be comparable with the group of individuals with symptoms constructed as part of a research project.

OBJECTIVES

The objective of this study was to seek to assess whether a community-based symptom survey can be harnessed in order to produce clinically relevant and reproducible populations within which studies of more detailed indicants could be undertaken.

METHOD

A total of 3629 patients registered with a general practice at Winterton, UK, were sent a questionnaire enquiring about 10 symptoms of possible oncological significance together with their consultation intention in relation to these symptoms. Up to 1 month later, an identical questionnaire was applied to all patients reporting at least one symptom, and more detailed information was obtained by research nurses on each symptom.

RESULTS

The overall response rate was 64.4%, and 850 patients reported one or more symptoms. For the majority of symptom reports, there was moderate to substantial agreement between the two applications of the questionnaire. The question on blood in the motions/toilet pan or on the toilet paper demonstrated almost perfect agreement. Slight agreement was found for abdominal pain for longer than 4 weeks and for black/tarry motions. In relation to the reliability of the patient consultation intention, there was substantial/moderate agreement for actions related to the majority of symptoms. For all symptoms, there was also a greater level of agreement for past activity than future intent.

CONCLUSION

The results of the study provide some support for a community survey as a mechanism to develop 'clinically relevant' populations for the iatrotropic symptoms rectal bleeding or indigestion/heartburn within which studies of more detailed indicants could be undertaken. There is also consistency with the work of others in relation to the numbers and characteristics of patients within the 'clinically relevant' population.

[Contrast-enhanced MR angiography in the routine work-up of the lower extremity arteries]

PURPOSE

Prospective evaluation of the effectiveness of contrast-enhanced moving-table magnetic resonance angiography (CE-MRA) as the sole routine tool for the diagnosis of peripheral arterial occlusive disease and determination whether it can replace catheter arteriography.

SUBJECTS AND METHODS

In a time period of 23 weeks, 100 consecutive patients were evaluated. A total of 112 contrast-enhanced moving-table MR angiograms were performed at 1.5 Tesla. A dedicated vascular coil system was used. It was evaluated in which cases MR angiography was sufficient to determine the treatment plan and in which cases limited quality required additional examinations.

RESULTS

In 93.75 % (105/112) of all examinations, the treatment plan was determined by MRA as the sole diagnostic tool. Twenty-two patients underwent surgery or percutaneous angioplasty based on MRA findings. Additional examinations due to impaired quality were performed in seven (6.25 %) cases: two MR angiographies of the pelvic arteries, one MR angiography of the calf, and four selective arteriographies because of venous overlay at the calf.

CONCLUSION

Contrast-enhanced MR angiography can take the place of catheter angiography in the routine work-up of patients with peripheral arterial occlusive disease. Further assessment might be necessary in five to ten percent of the cases when the diagnostic quality is inadequate, mostly due to venous overlay in the lower leg.

The potential of biomimesis in bone tissue engineering: lessons from the design and synthesis of invertebrate skeletons

Synthetic bone replacement materials are now widely used in orthopedics. However, to date, replication of trabecular bone structure and mechanical competence has proved elusive. Maximization of bone tissue attachment to replacement materials requires a highly organized porous structure for tissue integration and a template for assembly, combined with structural properties analogous to living bone. Natural structural biomaterials provide an abundant source of novel bone replacements. Animal skeletons have been designed through optimization by natural selection to physically support and physiologically maintain diverse tissue types encompassing a variety of functions. These skeletons possess structural properties that provide support for the complete reconstruction and regeneration of ectodermal, mesodermal, and bone tissues derived from animal and human and are thus suited to a diversity of tissue engineering applications. Increased understanding of biomineralization has initiated developments in biomimetic synthesis with the generation of synthetic biomimetic materials fabricated according to biological principles and processes of self-assembly and self-organization. The synthesis of complex inorganic forms, which mimic natural structures, offers exciting avenues for the chemical construction of macrostructures and a new generation of biologically and structurally related bone analogs for tissue engineering.

Interfacial synthesis of hollow microspheres of mesostructured silica

Hollow microspheres with ordered mesoporous walls are synthesised under ambient conditions by a simple procedure involving dilution and neutralisation of an aqueous tetraethoxysilane/cetyltrimethylammonium bromide reaction mixture.

The effects of HDV-insulin on carbohydrate metabolism in Type 1 diabetic patients

The aim of this study was to compare the metabolic effects of a single equimolar subcutaneous injection of hepatic directed vesicle-insulin (HDV-insulin) and regular insulin on glucose levels and intermediary metabolism during a 75-g oral glucose tolerance test (OGTT). Nine Type 1 diabetic patients underwent two experiments separated by 4 weeks. Each experimental protocol consisted of an identical evening meal followed by overnight euglycemic control achieved by a continuous low-dose insulin infusion. The next morning a subcutaneous injection (0.1 U/kg) of HDV-insulin or regular insulin was administered 30 min before a 75-g OGTT. The overnight basal insulin infusion was maintained unaltered throughout the 150-min OGTT. Plasma glucose, glucoregulatory hormones (insulin, glucagon, cortisol), and intermediary metabolites (lactate, alanine, glycerol, NEFA, beta-hydroxybutyrate) were measured to assess the metabolic effects of the two insulin preparations. Compared to regular insulin, an equivalent subcutaneous dose of HDV-insulin significantly lowered glucose levels during OGTT (mean reduction 2.2+/-0.4 mmol/l; P<.005). Plasma levels of insulin and glucagon were equivalent during both series of experiments. Blood lactate, glycerol and plasma NEFA levels were not different during OGTT indicating similar peripheral action of the insulins. beta-Hydroxybutyrate levels were significantly reduced (P<.05) following HDV-insulin supporting a preferential hepatic action of the preparation. We conclude that HDV-insulin can significantly lower plasma glucose excursions compared to an equivalent dose of regular insulin during an OGTT in Type 1 diabetic patients. The metabolic profile of equivalent peripheral insulin, glucagon and glycerol levels but reduced beta-hydroxybutyrate values support a hepatospecific effect of HDV-insulin.

Loss of annexin II heavy and light chains in prostate cancer and its precursors

Annexin II mRNA coding for a calcium binding protein was found to be absent in prostate cancer by subtractive hybridization and Northern analysis. In contrast to high expression in normal and benign hyperplastic glandular and basal epithelium, Annexin II heavy (p36) and light (p11) chains in 31/31 prostate cancer specimens were lost immunohistochemically. In glands involved by prostate intraepithelial neoplasia, 65% lost both chains in glandular epithelial cells, whereas basal cells were all positively stained. Southern analysis of cancer DNA showed no noticeable deletion in p36 gene. LNCaP cells treated with 5-azacytidine re-expressed p36, suggesting methylation could be responsible for the silencing.

Formation of BaSO4 fibres with morphological complexity in aqueous polymer solutions

BaSO4 fibres with morphological complexity were formed in aqueous solution with polyacrylate and partially monophosphonated poly(ethyleneoxide)-block-poly(methacrylic acid) additives by a simple precipitation reaction. For polyacrylate, formation of the fibrous deposits was strongly dependent on the level of supersaturation (S) and Ba2+:polymer molar ratio (R). At S = 60 to 80, and R = 3 to 14, highly anisotropic crystalline fibres consisting of bundles of BaSO4 nanofilaments were formed after several weeks, although the yield was low. The nanofilaments were also organized into cone-shaped aggregates at S = 80, and at lower R values these formed higher-order structures that consisted of multiple cone-on-cone assemblies with remarkable self-similarity. Increasing the supersaturation produced ovoid or cross-shaped dendritic particles for the range of molar ratios studied. In contrast, BaSO4 crystallisation in the presence of a partially phosphonated block copolymer gave a high yield of BaSO4 fibres up to 100 microm in length, and consisting of co-aligned bundles of 30 nm-diameter defect-free single-crystal nanofilaments with a uniform growth tip. A model for the defect-free growth of BaSO4 nanofilaments in aqueous polymer solutions based on amorphous precursor particles, vectorially directing forces and van der Waals attraction is proposed.

New-onset palpitations in general practice: assessing the discriminant value of items within the clinical history

BACKGROUND

Palpitations are non-specific, with less than half of patients experiencing palpitations having a cardiac arrhythmia. Currently it seems that there is little evidence available to assist GPs in discriminating between patients complaining of palpitations who have significant cardiac arrhythmias and those who do not.

OBJECTIVES

Our aim was to estimate discriminant functions for specific items of clinical information in relation to the categorization of a patient (aged over 18 years) with a symptom of new-onset palpitations presenting to primary care.

METHODS

A network of 62 GPs spread amongst 36 practices agreed to recruit patients with new-onset palpitations over the course of a 9-month study period. Patients consenting to be involved in the study were asked a number of questions, focusing particularly on the medical history, and were requested to complete a Hospital Anxiety and Depression Scale. Each patient was also provided with a RhythmCard cardiac event recorder for up to 2 weeks and was asked to record their heart rhythm if they experienced palpitations. Odds ratios (adjusted for age and sex) were used to compare the clinical information obtained from patients with the final diagnosis.

RESULTS

Of the 139 patients with palpitations presenting to GPs, it would appear that males [odds ratio = 2.1 (1.0-4.5)], those with regular palpitations [odds ratio = 2.5 (1.0-5.8)], those experiencing palpitations at work [odds ratio = 3.0 (1.3-7.2)] and those experiencing palpitations affected by sleeping (odds ratio = 3.3 (1.4-7.7)] were more likely to have a cardiac cause for their palpitations. Similar findings were made in an analysis focusing solely on the 81 patients with a RhythmCard result. Furthermore, amongst this group, it is interesting to note that patients with regular palpitations were more than twice as likely to have a 'significant' cardiac arrhythmia as a cause for their palpitations. There were suggestions of dose-response effects between the rate of the palpitation, the duration of the palpitation and the likelihood of it being a 'significant' arrhythmia.

CONCLUSIONS

This study provides some information on the characteristics of patients reporting palpitations to GPs who may have 'significant' cardiac arrhythmias. Based on this work, we believe that a larger community-based study would be worthwhile and would provide useful and useable clinical discriminant information for GPs in the settings where they work and amongst the types of patients they encounter.

Effect of morning exercise on counterregulatory responses to subsequent, afternoon exercise

The aim of this study was to determine whether a bout of morning exercise (EXE(1)) can alter neuroendocrine and metabolic responses to subsequent afternoon exercise (EXE(2)) and whether these changes follow a gender-specific pattern. Sixteen healthy volunteers (8 men and 8 women, age 27 +/- 1 yr, body mass index 23 +/- 1 kg/m(2), maximal O(2) uptake 31 +/- 2 ml x kg(-1) x min(-1)) were studied after an overnight fast. EXE(1) and EXE(2) each consisted of 90 min of cycling on a stationary bike at 48 +/- 2% of maximal O(2) uptake separated by 3 h. To avoid the confounding effects of hypoglycemia and glycogen depletion, carbohydrate (1.5 g/kg body wt po) was given after EXE(1), and plasma glucose was maintained at euglycemia during both episodes of exercise by a modification of the glucose-clamp technique. Basal insulin levels (7 +/- 1 microU/ml) and exercise-induced insulin decreases (-3 microU/ml) were similar during EXE(1) and EXE(2). Plasma glucose was 5.2 +/- 0.1 and 5.2 +/- 0.1 mmol/l during EXE(1) and EXE(2), respectively. The glucose infusion rate needed to maintain euglycemia during the last 30 min of exercise was increased during EXE(2) compared with EXE(1) (32 +/- 4 vs. 7 +/- 2 micromol x kg(-1) x min(-1)). Although this increased need for exogenous glucose was similar in men and women, gender differences in counterregulatory responses were significant. Compared with EXE(1), epinephrine, norepinephrine, growth hormone, pancreatic polypeptide, and cortisol responses were blunted during EXE(2) in men, but neuroendocrine responses were preserved or increased in women. In summary, morning exercise significantly impaired the body's ability to maintain euglycemia during later exercise of similar intensity and duration. We conclude that antecedent exercise can significantly modify, in a gender-specific fashion, metabolic and neuroendocrine responses to subsequent exercise.

Potassium channel receptor site for the inactivation gate and quaternary amine inhibitors

Many voltage-dependent K+ channels open when the membrane is depolarized and then rapidly close by a process called inactivation. Neurons use inactivating K+ channels to modulate their firing frequency. In Shaker-type K+ channels, the inactivation gate, which is responsible for the closing of the channel, is formed by the channel's cytoplasmic amino terminus. Here we show that the central cavity and inner pore of the K+ channel form the receptor site for both the inactivation gate and small-molecule inhibitors. We propose that inactivation occurs by a sequential reaction in which the gate binds initially to the cytoplasmic channel surface and then enters the pore as an extended peptide. This mechanism accounts for the functional properties of K+ channel inactivation and indicates that the cavity may be the site of action for certain drugs that alter cation channel function.

Circulating factors may be responsible for murine strain-specific responses to mobilizing cytokines

OBJECTIVE

To determine if circulating factors influence strain-specific responses to administration of hematopoietic stem-cell mobilizing cytokines, a murine model was employed.

METHODS

Plasma aliquots from intact DBA2, Balb/c, and C57Bl/6 mice were injected into intact Balb/c mice prior to delivery of mobilizing cytokines. Control Balb/c mice were injected with mobilizing cytokines alone. Plasma from hemi-body irradiated Balb/c mice, known to inhibit mobilization, was also injected into Balb/c mice. Twenty-four hours later, spleen cells were harvested and assayed for granulocyte-macrophage colony-forming cells (GM-CFC) and high-proliferative-potential colony-forming cells (HPP-CFC). Simultaneously harvested blood aliquots were assayed for CD45(+)/CD34(+) cells using flow cytometric techniques.

RESULTS

Mice receiving plasma from any source demonstrated significant inhibition of mobilization of HPP-CFC and GM-CFC to the spleen as compared to mobilized controls; for HPP-CFC, plasma from C57Bl/6 mice was more inhibitory than plasma from Balb/c (p = 0.001) or from DBA2 mice (p = 0.01), while for GM-CFC, plasma from C57Bl/6 mice was more inhibitory than Balb/c plasma but not more inhibitory than DBA2 plasma. Mice injected with plasma from previously irradiated Balb/c mice exhibited the expected HPP-CFC and GM-CFC mobilization inhibition, which was not statistically different from the inhibition seen in animals that received C57Bl/6 plasma. Mobilization of CD34(+)/CD45(+) cells to the blood also appeared to be inhibited by pretreatment with C57Bl/6 plasma, but not DBA2 plasma.

CONCLUSION

These data suggest that strain-specific patterns of mobilization may be influenced by a circulating mobilization inhibitor(s).

Effects of antecedent prolonged exercise on subsequent counterregulatory responses to hypoglycemia

In the present study the hypothesis tested was that prior exercise may blunt counterregulatory responses to subsequent hypoglycemia. Healthy subjects [15 females (f)/15 males (m), age 27 +/- 1 yr, body mass index 22 +/- 1 kg/m(2), hemoglobin A(Ic) 5.6 +/- 0.5%] were studied during 2-day experiments. Day 1 involved either 90-min morning and afternoon cycle exercise at 50% maximal O2 uptake (VO2(max)) (priorEXE, n = 16, 8 m/8 f) or equivalent rest periods (priorREST, n = 14, 7 m/7 f). Day 2 consisted of a 2-h hypoglycemic clamp in all subjects. Endogenous glucose production (EGP) was measured using [3-3H]glucose. Muscle sympathetic nerve activity (MSNA) was measured using microneurography. Day 2 insulin (87 +/- 6 microU/ml) and plasma glucose levels (54 +/- 2 mg/dl) were equivalent after priorEXE and priorREST. Significant blunting (P < 0.01) of day 2 norepinephrine (-30 +/- 4%), epinephrine (-37 +/- 6%), glucagon (-60 +/- 4%), growth hormone (-61 +/- 5%), pancreatic polypeptide (-47 +/- 4%), and MSNA (-90 +/- 8%) responses to hypoglycemia occurred after priorEXE vs. priorREST. EGP during day 2 hypoglycemia was also suppressed significantly (P < 0.01) after priorEXE compared with priorREST. In summary, two bouts of exercise (90 min at 50% VO2(max)) significantly reduced glucagon, catecholamines, growth hormone, pancreatic polypeptide, and EGP responses to subsequent hypoglycemia. We conclude that, in normal humans, antecedent prolonged moderate exercise blunts neuroendocrine and metabolic counterregulatory responses to subsequent hypoglycemia.

Synthesis of mesoporous silica monoliths with embedded nanoparticles

Mesostructured silica-nanoparticle monolithic composites have been synthesized by dispersing prefabricated nanoparticles of gold or zeolite (silicalite) in ethanolic reaction mixtures containing SiCl4 and a Pluronic triblock copolymer template. Whereas silicalite nanoparticles were used directly, surface functionalization of the gold nanoparticles with either primed silicate ions or a discrete 3-5-nm-thick silica shell was required to increase the interfacial compatibility with the hydrophilic poly(ethylene oxide) blocks. Under these conditions, the resulting monoliths consisted of distributed nanoparticles within an ordered mesostructured silica matrix. Removal of the polymer template by calcination produced corresponding mesoporous silica-nanoparticle replicas. The combination of the structure and the porosity of the silica framework with the crystal chemical properties of the embedded nanoparticles suggests that such composites should be useful as multifunctional materials.

Benefits of pravastatin on cardiovascular events and mortality in older patients with coronary heart disease are equal to or exceed those seen in younger patients: Results from the LIPID trial

BACKGROUND

The effect of cholesterol-lowering therapy on death from coronary heart disease in older patients with previous coronary heart disease and average cholesterol levels is uncertain.

OBJECTIVE

To compare the relative and absolute effects of pravastatin on cardiovascular disease outcomes in patients with coronary heart disease who are 65 years of age or older with those in patients 31 to 64 years of age.

DESIGN

Subgroup analysis of a randomized, placebo-controlled trial.

SETTING

87 centers in Australia and New Zealand.

PATIENTS

3514 patients 65 to 75 years of age, chosen from among 9014 patients with previous myocardial infarction or unstable angina and a baseline plasma cholesterol level of 4.0 to 7.0 mmol/L (155 to 271 mg/dL).

INTERVENTION

Pravastatin, 40 mg/d, or placebo.

MEASUREMENTS

Major cardiovascular disease events over 6 years.

RESULTS

Older patients were at greater risk than younger patients (31 to 64 years of age) for death (20.6% vs. 9.8%), myocardial infarction (11.4% vs. 9.5%), unstable angina (26.7% vs. 23.2%), and stroke (6.7% vs. 3.1%) (all P < 0.001). Pravastatin reduced the risk for all cardiovascular disease events, and similar relative effects were observed in older and younger patients. In patients 65 to 75 years of age, pravastatin therapy reduced mortality by 21% (CI, 7% to 32%), death from coronary heart disease by 24% (CI, 7% to 38%), coronary heart disease death or nonfatal myocardial infarction by 22% (CI, 9% to 34%), myocardial infarction by 26% (CI, 9% to 40%), and stroke by 12% (CI, -15% to 32%). For every 1000 older patients treated over 6 years, pravastatin prevented 45 deaths, 33 myocardial infarctions, 32 unstable angina events, 34 coronary revascularization procedures, 13 strokes, or 133 major cardiovascular events, compared with 22 deaths and 107 major cardiovascular events per 1000 younger patients. Among older patients, the numbers needed to treat were 22 (CI, 17 to 36) to prevent one death from any cause, 35 (CI, 24 to 67) to prevent one death from coronary heart disease, and 21 (CI, 17 to 31) to prevent one coronary heart disease death or nonfatal myocardial infarction.

CONCLUSIONS

In older patients with coronary heart disease and average or moderately elevated cholesterol levels, pravastatin therapy reduced the risk for all major cardiovascular events and all-cause mortality. Since older patients are at greater risk than younger patients for these events, the absolute benefit of treatment is significantly greater in older patients.

Identification of differentially expressed genes in organ-confined prostate cancer by gene expression array

BACKGROUND

To understand the molecular mechanisms underlying prostate cancer, we have utilized the gene expression array to search for genes whose expression is altered in this disease.

METHODS

RNA quality from manual microdissected tissue was compared with that from microselected tissue by electrophoresis. For array analysis, malignant and normal prostate epithelium was enriched using microselection technique from prostate cancer and the peripheral zone of a normal prostate. Identical array membrane was hybridized to labeled cancer and normal cDNA, respectively. The differentially expressed gene was further evaluated by RT-PCR.

RESULTS

Microdissection, but not microselection, causes visible degradation to RNA. Of the 588 genes on the membrane, 87 genes yielded significant signals. Based on a three fold difference relative to normal prostate tissue, 1 gene was overexpressed and 12 genes underexpressed in prostate cancer. Of them, five showed statistically significant reduction in mRNA levels in six prostate cancer specimens compared with seven normal prostate specimens. These five genes are glutathione S-transferase M1 (GSTM1), monocyte chemotactic protein-1 (MCP-1), tumor necrosis factor-alpha receptor-1 (TNFR-1), transforming growth factor beta3 (TGF-beta3), and inhibitor of DNA binding-1 (ID-1).

CONCLUSIONS

GST-based metabolism, cytokine MCP-1 and TNFR-1, and TGF-beta3 signaling pathways, and some helix-loop-helix nuclear proteins could be potentially important in organ-confined prostate cancer and deserve further investigation.

Chromosomal positioning of human T-lymphotropic type 1 proviruses by fluorescence in situ hybridisation

Fluorescence in situ hybridisation (FISH) was employed to identify the chromosomal integration site of the human T-cell lymphotropic virus, type 1 (HTLV-1) present in T-cell clones derived from HTLV-1-infected individuals and a virally transformed cell line, C8166-45. Proviral sequences were detected in C8166-45 but not uninfected Jurkat cells. Integration sites were reliably detected in T-cell clones determined previously to be infected with HTLV-1. The results indicated that the transformed cell line and some of the T-cell clones possessed more than one proviral integration site. This hybridisation system is useful for determining the number of integration events and for localising proviruses to specific chromosomal regions.

The medical interview: differences between adult and geriatric outpatients

BACKGROUND

There is a perception that primary care physicians spend less time with older patients and little is known about physician and older patient satisfaction during clinical encounters.

OBJECTIVE

To determine how primary care interviews of geriatric patients differ from those of other adults.

DESIGN

Descriptive, analytic study.

SETTING

Ten primary care sites in the United States and one in Canada, including public, voluntary, and private clinics and practices.

PARTICIPANTS

Of the 544 patients, 45.6% were 65 and older and 17.8% were 75 or older. There were 127 participating physicians.

MEASUREMENTS

Encounters were audiotaped and analyzed. Patients and physicians also completed exit questionnaires.

RESULTS

Interview length increased significantly with age for men but not for women. Physician satisfaction did not change as patient age increased. Patient satisfaction, on the other hand decreased with age among women but not for men. Although physicians' and younger patients' perceptions of health were moderately associated, there was no association for men ages 75 and over.

CONCLUSIONS

There is no evidence that physicians spend less time or are more uncomfortable with older patients. Both physician and male patient satisfaction remain stable with increasing patient age, despite greater disparity in patient and physician perceptions of health. Older female patients are less satisfied with physician visits than their younger counterparts, in the absence of changes in interview length or disparities between older female patients and their physicians in health perception.

[Possibilities and limits of interventional therapy in necrotizing pancreatitis]

We present a new technique for minimal invasive radiological assisted necrosectomy (MIRAN) for infected necrosis in acute pancreatitis. We describe how to place volumic catheters for fragmentation and extraction of necrotic material. In addition a new technique is described for minimal invasive occlusion of selected pancreas tail to avoid fistulas. In 26 patients with infected necrosis of the pancreatic region, 12 patients (46.2%) could be healed by MIRAN alone. 5 patients (19.2%) could be satisfactory treated with a combination of MIRAN and operative necrosectomy. 9 patients (34.6%) died, 5 of them postoperatively. In 7 cases death followed multiple organ failure/dysfunction syndrome. 12 (71%) of 17 patients with the aim of curative treatment could be satisfactory treated with MIRAN. 2 other patients (12%) received additional surgery, 3 patients died (17%), 2 of them without any other treatment. The advantages of MIRAN are reduced trauma, general anaesthesia is not necessary, no difficult surgical preparation is necessary, no limits for additional therapy, reduced damage of neighbouring organs and vital pancreatic tissue as well as avoiding splenectomy.

Estrogen receptor beta expression in invasive breast cancer

The aim of this work was to determine the extent of estrogen receptor beta (ER-beta) expression in invasive breast cancer (BrCA) and whether ER-beta expression is correlated with response to adjuvant hormonal therapy with tamoxifen (AHTT). Immunohistochemical staining (IHC) for estrogen receptor alpha (ER-alpha) and ER-beta was performed on sections of formalin-fixed and paraffin-embedded tissue from 47 unselected invasive breast carcinomas (BrCA). IHC for ER-beta was also performed on sections of BrCA from 118 women who were treated with mastectomy and AHTT. Survival analysis was performed using the Kaplan-Meier method and the log-rank test. Of the 47 unselected BrCA, 17 (36%) were negative for ER-alpha and of these, 8 (47% of ER-alpha negative cases and 17% of all 47 patients) were ER-beta positive. Five of the 8 ER-alpha negative and ER-beta positive cases were positive for ER biochemically. There was no correlation between ER-beta positivity and overall survival in the unselected group. By contrast, in the group of women treated with AHTT, expression of ER-beta in more than 10% of cancer cells was associated with better survival (P = .0077), even in women with node-negative BrCA (P = .0069). In conclusion, our results show that a significant number of women with BrCA are positive for ER-beta only, and may be determined to be ER-negative when currently available IHC is used. ER-beta status is a significant predictor of response to AHTT in women with BrCA. Larger studies with multivariate analysis are needed to confirm these findings.

Effects of differing durations of antecedent hypoglycemia on counterregulatory responses to subsequent hypoglycemia in normal humans

The aim of this study was to determine whether the duration of antecedent hypoglycemia regulates the magnitude of subsequent counterregulatory failure. A total of 31 lean healthy overnight-fasted individuals (16 men/15 women) were studied. There were 15 subjects (8 men/7 women) who underwent two separate 2-day randomized experiments separated by at least 2 months. On day 1, 2-h hyperinsulinemic (9 pmol x kg(-1) x min(-1)) euglycemic (5.2 +/- 0.1 mmol/l) or hypoglycemic (2.9 +/- 0.1 mmol/l) glucose clamps (prolonged hypoglycemia) were carried out in the morning and afternoon. Of the other subjects, 16 participated in a 2-day study in which day 1 consisted of morning and afternoon short-duration hypoglycemia experiments (hypoglycemic nadir of 2.9 +/- 0.1 mmol for 5 min), and 10 of these individuals underwent an additional 2-day study in which day 1 consisted of morning and afternoon intermediate-duration hypoglycemia (hypoglycemic nadir of 2.9 +/- 0.1 mmol for 30 min). The next morning (day 2) all subjects underwent an additional 2-h hyperinsulinemic-hypoglycemic clamp (2.9 +/- 0.1 mmol/l). The rate of fall of glucose (0.07 mmol/min) was carefully controlled during all hypoglycemic studies so that the glucose nadir was reached at 30 min. Despite equivalent day 2 plasma glucose and insulin levels, there were significant differences in counterregulatory physiological responses. Steady-state epinephrine, glucagon, growth hormone, cortisol, and pancreatic polypeptide levels were similarly significantly blunted (P < 0.01) by the differing duration day 1 hypoglycemia compared with day 1 euglycemia. Muscle sympathetic nerve activity and endogenous glucose production were also similarly blunted (P < 0.01) by day 1 hypoglycemia (relative to day 1 euglycemia). Day 2 hypoglycemic symptoms were significantly reduced (P < 0.01) after day 1 prolonged intermediate- but not short-duration hypoglycemia. In summary, two episodes of short-duration moderate hypoglycemia can produce significant blunting of key neuroendocrine and metabolic counterregulatory responses. Hypoglycemic symptom scores are reduced by prolonged but not short-duration prior hypoglycemia. We conclude that in healthy overnight fasted humans, 1) neuroendocrine, autonomic nervous system, and metabolic counterregulatory responses are sensitive to the blunting effects of even short-duration prior hypoglycemia, and 2) the duration of antecedent hypoglycemia results in a hierarchy of blunted physiological responses with hypoglycemic symptom awareness less vulnerable than neuroendocrine responses.

A discussion of potential exposure metrics for use in epidemiological studies on human exposure to radiowaves from mobile phone base stations

There is currently a high level of concern in many countries that exposure to radiowaves from mobile phone base stations may be hazardous to health. When investigating such suggested risks, epidemiologists need to define an exposure metric that can reliably discriminate between exposed and unexposed groups of people. We conducted a feasibility study to investigate if either short-term measurements of electric field strength, calculations of electric field strength, or distance from nearby mobile phone base stations could be used to develop a metric reflecting an individual's exposure to radiowaves. With electric field strengths in the range of 0.012-0.343 V/m, radiowaves from mobile phone base stations were found to give a material contribution to total exposure; however, stronger signals were frequently measured from other sources such as broadcast radio and television transmitters. Theoretical considerations and the measurements made during this work demonstrated that studies at the population level on suggested adverse effects of radiowaves from mobile phone base stations are not feasible since no valid metric for estimating historical exposures is currently available. The pace of radio infrastructure development is also such that today's measurements are unlikely to be good proxies for either past or future exposures. The complex propagation characteristics affecting the beams from base station antennas include shielding effects and multiple reflections from house walls and other buildings. These factors, combined with the presence of other environmental sources of radiowaves, cause distance from a base station to be a poor proxy for exposure to radiowaves indoors. It may be possible to adapt computer models developed by network providers to predict network coverage for epidemiological purposes; however, this has yet to be investigated. Furthermore, there is little evidence that presently justifies epidemiological studies being restricted to adverse effects of radiowaves from mobile phone base stations while neglecting radiowaves at other frequencies produced by different transmitters.

Pretransplant tumor antigen-specific immunization of allogeneic bone marrow transplant donors enhances graft-versus-tumor activity without exacerbation of graft-versus-host disease

Allogeneic bone marrow transplantation (BMT) causes a beneficial graft-versus-tumor (GVT) immune response that is often associated with graft-versus-host disease (GVHD). There is substantial interest in developing therapeutic strategies that augment GVT without GVHD. We have demonstrated recently that immunization of BMT donors with cellular tumor vaccines leads to curative GVT but induces unacceptable GVHD because of the presence of recipient minor histocompatibility antigens (mHAgs) in whole-cell tumor vaccines. This study tested the hypothesis that immunization of BMT donors against a defined tumor-specific antigen with a vaccine not containing recipient mHAgs would help to separate the two responses by enhancing GVT activity without exacerbating GVHD, even when cellular vaccines were used after BMT. Recipient strain C57BL/6 fibrosarcoma cells engineered to express the well-characterized model tumor antigen, influenza nucleoprotein (NP), were used in these studies. C3H.SW donors were immunized against NP prior to BMT, and cytolytic T cells were transferred along with bone marrow into irradiated H-2-matched, mHAg-mismatched C57BL/6 recipients with established micrometastatic 205-NP tumors. Donor immunization led to a significant increase in GVT activity, as measured by reduction in tumor growth and enhanced survival. However, deaths in recipients of tumor antigen-specific immune BMT ultimately occurred because of the growth of antigen-loss variants; such tumor growth did not occur in animals receiving BMT from donors treated with whole-cell vaccines. Donor immunization did not lead to an exacerbation of GVHD, even when BMT recipients received additional immunization after BMT with a 205-NP "whole" tumor cell vaccine (which was shown to induce fatal GVHD when used for donor immunization). In conclusion, immunization of allogeneic BMT donors against a tumor-specific antigen significantly enhances GVT activity without an associated exacerbation of GVHD.

[Carotid endarterectomy and carotid stenting. A pilot study of a prospective, randomized and controlled comparison]

INTRODUCTION

A prospective, randomized and controlled trial is conducted to compare carotid endarterectomy and carotid stenting in high grade symptomatic carotid artery stenoses.

METHODS

According to the study design symptomatic patients with a angiographically high-grade (> or = 70%) internal carotid artery stenosis are included. Pre- and postinterventional diagnostics during the hospitalization period includes neurological assessment, duplex sonography of the cervical and cerebral arteries and magnetic resonance imaging of the brain. Follow-up examinations are scheduled after 1, 6 and 12 months and consist of a neurological assessment and duplex sonography. After 12 months selective angiography and magnetic resonance imaging of the brain will be performed additionally. During a period of 9 months up to now 23/137 patients treated for a carotid artery stenosis were included in the study, 11 patients underwent surgery and 12 patients carotid stenting.

RESULTS

Carotid stenting and endarterectomy was primarily successful without residual stenosis > 30% in each patient without the occurrence of stroke or death. In 18 follow-up examinations (neurological assessment including duplex sonography) of 13 patients (13 follow-up examinations after 30 days, 5 after 6 months) no relevant restenosis and no stroke occurred.

CONCLUSION

As of yet, carotid stenting was a safe procedure. Due to the small number of patients a definitive conclusion can not be drawn.

A novel mutation, Ala315Ser, in FGFR2: a gene-environment interaction leading to craniosynostosis?

Mutations in the fibroblast growth factor receptor 1, 2 and 3 (FGFR1, -2 and -3) and TWIST genes have been identified in several syndromic forms of craniosynostosis. There remains, however, a significant number of patients with non-syndromic craniosynostosis in whom no genetic cause can be identified. We describe a novel heterozygous mutation of FGFR2 (943G --> T, encoding the amino acid substitution Ala315Ser) in a girl with non-syndromic unicoronal craniosynostosis. The mutation is also present in her mother and her maternal grandfather who have mild facial asymmetry but do not have craniosynostosis. None of these individuals has the Crouzonoid appearance typically associated with FGFR2 mutations. However, the obstetric history revealed that the proband was in persistent breech presentation in utero and was delivered by Caesarean section, at which time compression of the skull was apparent. We propose that this particular FGFR2 mutation only confers a predisposition to craniosynostosis and that an additional environmental insult (in this case foetal head constraint associated with breech position) is necessary for craniosynostosis to occur. To our knowledge, this is the first report of an interaction between a weakly pathogenic mutation and intrauterine constraint, leading to craniosynostosis.

Structure of the cytoplasmic beta subunit-T1 assembly of voltage-dependent K+ channels

The structure of the cytoplasmic assembly of voltage-dependent K+ channels was solved by x-ray crystallography at 2.1 angstrom resolution. The assembly includes the cytoplasmic (T1) domain of the integral membrane alpha subunit together with the oxidoreductase beta subunit in a fourfold symmetric T1(4)beta4 complex. An electrophysiological assay showed that this complex is oriented with four T1 domains facing the transmembrane pore and four beta subunits facing the cytoplasm. The transmembrane pore communicates with the cytoplasm through lateral, negatively charged openings above the T1(4)beta4 complex. The inactivation peptides of voltage-dependent K(+) channels reach their site of action by entering these openings.

Bridging the gap. Community partnerships in nursing education: advancing primary health care in practice

An innovative approach to nursing education was piloted by the School of Nursing at Flinders University and Noarlunga Health Services, a generic community health service, in Adelaide, South Australia. The approach, encapsulated in the four-year Community Enrichment Project (CEP), focused on Primary Health Care (PHC) and nursing practice. The CEP developed curriculum and organised student placements, which promoted understanding of PHC in a way that integrated acute and community sectors. This paper considers the impact of splitting the students' third year final practicum, of seven weeks, between acute and community placements. Integral to the overall outcome of the project was the community agencies' cooperation in accepting students for longer clinical placements than had previously been the norm. This resulted in students being engaged in activities and projects in diverse areas. The students were aided in linking PHC theory to practice by the CEP team members who mentored them throughout these placements. Outcomes demonstrated the ability of students to integrate PHC theory to practice, across a variety of health settings. Students moved from a position of little knowledge or understanding of PHC, to an integrated knowledge of PHC principles and the relationship to enhanced nursing practice.

Disseminated mucormycosis due to Saksenaea vasiformis in an immunocompetent adult

A case of disseminated infection due to Saksenaea vasiformis in a previously well adult male is presented. The clinical presentation was that of septic shock with a distinctive rash. At postmortem, endocarditis and widespread dissemination were evident.

Motion determination in actin filament fluorescence images with a spatio-temporal orientation analysis method

We present a novel approach of automatically measuring motion in series of microscopic fluorescence images. As a differential method, the three-dimensional structure tensor technique is used to calculate the displacement vector field for every image of the sequence, from which the velocities are subsequently derived. We have used this method for the analysis of the movement of single actin filaments in the in vitro motility assay, where fluorescently labeled actin filaments move over a myosin decorated surface. With its fast implementation and subpixel accuracy, this approach is, in general, very valuable for analyzing dynamic processes by image sequence analysis.

Plasmapheresis combined with continuous venovenous hemofiltration in surgical patients with sepsis

OBJECTIVE

To examine the effect of continuous venovenous hemofiltration (CVVHF) combined with plasmapheresis (TPE) in critically ill surgical patients after treatment of the septic focus.

DESIGN

Observational pilot study.

SETTING

University teaching hospital intensive care unit.

INTERVENTIONS

TPE and CVVHF were administered 24 h after surgical and/or interventional treatment of septic focus. Arterial blood pressure, cardiac output, and systemic vascular resistance values were monitored. We examined the effect of the combined extracorporeal detoxification on outcome related to age, morbidity, organic failure rate, and initial APACHE II score.

MEASUREMENTS AND RESULTS

Forty-three patients with sepsis were treated; 19 received TPE in combination with CVVHF, and 24 did not receive extracorporeal therapy. Overall mortality was 44.2%. In the therapy group mortality was lower (42.1 vs. 45.8%), but the primary organic failure rate was higher. The relationship between mortality and age was similar in the two groups. There was also no difference between the groups in the course of scores on APACHE II, multiple-organ failure, and sepsis severity. Only patients with an initial APACHE II score of 21-25 had a significant reduction in mortality after combined extracorporeal detoxification. Mortality of 17% in TPE/CVVHF patients with single- (pulmonary) and double-organ failure (renal/pulmonary) was significantly lower (P < 0.0001) than in untreated patients.

CONCLUSIONS

Reduction in mortality in single- and double-organ failure was as high as 28% in septic patients with combined extracorporeal detoxification. A prospective randomized trial in sepsis and double-organ failure should be projected.

[Emotional experience, expression and communication in musical improvization. A qualitative-quantitative single case study]

In this study the theory-conducted empirical procedure for analyzing active improvisatory music therapy of a single case will be described. The operationalization and tests for validation will be described. According to the aim of the study, the results show that the used method is appropriate to describe different and repetitive (emotional) patterns of improvisatory playing, which reflect the personal (emotional) and interpersonal pathology and healthy parts of the examined patient. With the aid of several tests the results of validating the macro-process will be discussed.

Quality of nucleic acids extracted from fresh prostatic tissue obtained from TURP procedures

PURPOSE

The molecular genetic study of benign prostatic hyperplasia (BPH) requires high quality nucleic acids from BPH tissue. It has been generally assumed, but not experimentally proven, that the diathermy used in trans-urethral resection of the prostate (TURP) damages nucleic acids.

MATERIALS AND METHODS

Total RNA, polyA+ RNA and genomic DNA isolated from fresh tissue obtained from TURP procedures were compared with those isolated from tissue obtained from open prostatectomy.

RESULTS

On a formaldehyde agarose gel, there was an increase in low molecular weight RNA in the TURP derived samples, in comparison to that in the open prostatectomy derived samples. The 28S and 18S rRNA were present in all TURP specimens and although the two bands were reduced in some samples, there were samples in which the 2 bands were indistinguishable from the open prostatectomy derived samples. Low molecular weight fragments seen in total RNA were reduced greatly in polyA+ RNA and the difference in polyA+ RNA between the TURP and open prostatectomy derived samples was significantly diminished. RT-PCR of two ubiquitously expressed gene transcripts (Galpha11, 256 bp and HPRT, 847 bp) yielded products of similar size and intensity between TURP and open prostatectomy derived samples. Genomic DNA obtained from TURP derived specimens showed no difference in size or enzyme digestibility in comparison to that from open prostatectomy.

CONCLUSIONS

Nucleic acids extracted from fresh prostatic tissue derived from TURP procedures can be used as readily as any other fresh tissue for RT-PCR based molecular genetic studies, although polyA+ RNA isolation is recommended if degradation-free RNA is required.