Usefulness of discography, discoblock and a new mechanical method for identifying a painful segment/disc.

BACKGROUND: We previously described a procedure for eliciting deep spatial discrimination of individual segments in the healthy lumbar spine of normal subjects: the percutaneous mechanical provocation (PMP) test. Our goal was to devise a method for accurate identification of the spinal level of pathology in chronic low back pain (CLBP). In the present study, we validated the PMP test, using a subgroup of CLBP patients with isthmic spondylolisthesis (IS). Because there is clinical consensus that IS back pain originates in the slipped segment/disc, the level of pathology can be directly compared to the result of the PMP test. The test is agnostic with respect to the underlying pathological mechanism, and therefore might be useful in identifying the involved segment(s) irrespective of the painful structure. METHODS: In 37 patients with confirmed IS (slippage 3-15mm), we compared sensitivity between the PMP test, the widely used provocative discography test and the discoblock test. RESULTS: The PMP test reliably identified the slip level in patients with IS, with sensitivity of 92%. Accepting the slipped disc as the origin of pain in IS, the sensitivity of the provocative discography and discoblock tests were 49% and 35%, respectively: i.e., too low to be contributive in clinical practice. CONCLUSIONS: The PMP test reliably identified the origin of localized pain in IS as the slip level, but should be used with care in CLBP patients in selecting discogenic pain patients for fusion surgery, since the specificity of the test is not known and it may be positive for any origin of localized pain.

Tadalafil increases muscle capillary recruitment and forearm glucose uptake in women with type 2 diabetes.

AIMS/HYPOTHESIS: Recent evidence suggests that reduced synthesis of nitric oxide in endothelial cells, i.e. endothelial dysfunction, contributes to the impaired action of insulin in the vasculature of patients with type 2 diabetes. We investigated whether selective inhibition of phosphodiesterase-5 by tadalafil has beneficial effects on peripheral microcirculation and glucose uptake in these patients. METHODS: We enrolled seven postmenopausal women with type 2 diabetes and ten age-matched healthy women as controls in a placebo-controlled study to evaluate the acute metabolic effects of tadalafil. We performed microdialysis and blood flow measurements in muscle, and sampled arterial and deep venous blood before and after a single dose of tadalafil 20 mg or placebo. Circulating glucose and insulin levels, muscle capillary recruitment as reflected by permeability surface area for glucose (PS(glu)) and forearm glucose uptake were measured. RESULTS: In women with type 2 diabetes, but not in the control group, tadalafil induced increases in the incremental AUC for PS(glu) (tadalafil vs placebo 41 +/- 11 vs 4 +/- 2 ml [100 g](-1) min(-1), p < 0.05) and forearm glucose uptake (46 +/- 9 vs 8 +/- 4 micromol [100 g](-1) min(-1), p < 0.05). The variable that best predicted forearm glucose uptake was PS(glu), which explained 70% of its variance. However, fasting glucose and insulin concentrations were similar following treatment with placebo or tadalafil in the two groups. CONCLUSIONS/INTERPRETATION: This study suggests that tadalafil evokes positive metabolic effects in insulin-resistant women with type 2 diabetes.

Out-of-hospital cardiac arrest: Causes according to autopsy and electrocardiography - Analysis of 781 patients with neither hospital care nor prescribed medication during the preceding two years.

BACKGROUND: There is a knowledge gap regarding aetiology of and potential for predicting out-of-hospital cardiac arrest (OHCA) among individuals who are healthy before the event. AIM: To describe causes of OHCA and the potential for predicting OHCA in apparently healthy patients. METHODS: Patients were recruited from the Swedish Register of Cardiopulmonary Resuscitation from November 2007 to January 2011. Inclusion criteria were: OHCA with attempted CPR but neither dispensed prescription medication nor hospital care two years before the event The register includes the majority of patients suffering OHCA in Sweden where cardiopulmonary resuscitation (CPR) was attempted. Medication status was defined by linkage to the Swedish Prescribed Drug Register. Cause of death was assessed based on autopsy and the Swedish Cause of Death Register. Prediction of OHCA was attempted based on available electrocardiograms (ECG) before the OHCA event. RESULTS: Altogether 781 individuals (16% women) fulfilled the inclusion criteria. Survival to 30 days was 16%. Autopsy rate was 72%. Based on autopsy, 70% had a cardiovascular aetiology and 59% a cardiac aetiology. An ECG recording before the event was found in 23% of cases. The ECG was abnormal in 22% of them. CONCLUSION: Among OHCA victims who appeared to be healthy prior to the event, the cause was cardiovascular in the great majority according to autopsy findings. A minority had a preceding abnormal ECG that could have been helpful in avoiding the event.

Muscle-spindle histochemistry.

Reduced nicotinamide adenine dinucleotide tatrazolium reductase is abundant in cat intrafusal muscle fibers, whereas in the toad its activity is equal to that in extrafusal fibers. Spindles of both species contain little fat. In sections stained for adenosine triphosphatase bound to myofibrils, two types of intrafusal muscle fibers appear in spindles of both the cat and toad.

Noradrenaline nerve terminals in human cerebral cortices: first histochemical evidence.

The cerebral and cerebellar cortices of man are richly provided with varicose noradrenaline nerve terminals, which are visualized by fluorescence histochemistry of brain smears obtained by a new technique. The density of such nerves in human cortices equals that of the rat. The method permits simple and rapid analysis of noradrenergic nerves of the human cortex during routine neurosurgical operations.

The effect of Russian Maternity Home routines on breastfeeding and neonatal weight loss with special reference to swaddling.

BACKGROUND: Few investigations have considered evaluating the effects of certain combinations of ward routines like swaddling of the baby and separation of mother and baby on infant variables such as neonatal weight loss. AIMS: To study the effect of different ward routines in respect to proximity to mother and type of infant apparel, on breastfeeding parameters (amount of ingested milk, volume of supplements, number of breastfeeds, total duration of breastfeeding time) day 4 after birth as well as recovery from neonatal weight loss and infant's weight on day 5. STUDY DESIGN AND SUBJECTS: In a randomized trial with factorial design four treatment groups including 176 mother-infant dyads were studied 25-120 min after birth. Randomized treatments focused on care routines administered to the infants after delivery and later in the maternity ward as well as to the type of clothing the infants received. Group 1 infants were placed skin-to-skin with their mothers after delivery, and had rooming-in while in the maternity ward. Group 2 infants were dressed and placed in their mothers' arms after delivery, and roomed-in with mothers in the maternity ward. Group 3 infants were kept in the nursery both after birth and while their mothers were in the maternity ward. Group 4 infants were kept in the nursery after birth, but roomed-in with their mothers in the maternity ward. Equal numbers of infants were either swaddled or clothed in baby attire. Breastfeeding parameters were documented during day 4 after birth. Infant's weight was measured daily. RESULTS: Babies who were kept in the nursery received significantly more formula and significantly less breast-milk, than did babies who roomed-in with their mothers. Swaddling did not influence the breastfeeding parameters measured. However, swaddled babies who had experienced a 2-h separation period after birth and then were reunited with their mothers tended to have a delayed recovery of weight loss compared to those infants who were exposed to the same treatment but dressed in clothes. Furthermore, swaddled babies who were kept in the nursery and received breast-milk supplements had a significantly delayed recovery of weight loss after birth when compared to those infants ingesting only breast-milk. On day 5, regression analyses of predicted weight gain in the exclusively breastfed infants indicated a significant increase per 100 ml breast-milk (59 g), compared to the predicted weight gain on day 5 per 100 ml supplements in the swaddled babies (14 g) (P=0.001). CONCLUSION: Supplements given to the infants in the nursery had a negative influence on the amount of milk ingested. In addition, supplement feeding or a short separation after birth when combined with swaddling was shown to have a negative consequence to infant weight gain.

Ischemia-induced shift of inhibitory and excitatory amino acids from intra- to extracellular compartments.

Brain ischemia was induced for 10 or 30 min by clamping the common carotid arteries in rabbits whose vertebral arteries had previously been electrocauterized. EEG and tissue content of high energy phosphates were used to verify the ischemic state and to evaluate the degree of postischemic recovery. Extracellular levels and total contents of amino acids were followed in the hippocampus during ischemia and 4 h of recirculation. At the end of a 30-min ischemic period, GABA had increased 250 times, glutamate 160 times, and aspartate and taurine 30 times in the extracellular phase. The levels returned to normal within 30 min of reflow. A delayed increase of extracellular phosphoethanolamine and ethanolamine peaked after 1-2 h of reflow. Ten minutes of ischemia elicited considerably smaller but similar effects. With respect to total amino acids in the hippocampus, glutamate and aspartate decreased to 30-50% of control while GABA appeared unaffected after 4 h of reflow. Alanine, valine, phenylalanine, leucine, and isoleucine increased severalfold. The importance of toxic extracellular levels of excitatory amino acids, as well as of high extracellular levels of inhibitory amino acids, are considered in relation to the pathophysiology of neuronal cell loss during cerebral ischemia.

New technology for sterilization and disinfection.

Sterilization with low temperature steam and formaldehyde is a well-known process in many European countries, but little known in the United States. It sterilizes reliably and reproducibly at temperatures greater than or equal to 65 degrees C. With a well-designed cycle, it leaves residues of formaldehyde on sterilized items below 5 micrograms/cm2, measured on a standard filter paper. Formaldehyde levels in air near the autoclave are well below official exposure limits, if at all measurable. Occurrence of late growers in bioindicators, and penetration of the sterilizing media into long narrow lumina, should be validated for new processes. Automated cleaning and disinfection in closed washer-disinfectors and flushing disinfectors are likewise processes relatively little known in the United States. Disinfection is achieved by a final rinse with hot water or steam. Washer-disinfectors are used for surgical instruments, nondisposable anesthesia and other equipment, flushing disinfectors for nondisposable bedpans, wash-bowls, urinals, and similar equipment. They clean well, washer-disinfectors excellently so, and disinfect reliably. With the use of such equipment in wards, surgical departments, and other areas, reliance on chemical germicides can be dramatically reduced and disposables can be replaced by disinfectable nondisposables.

Nosocomial Legionnaires' disease following renal transplantation.

A cluster of five cases of Legionnaires' disease in renal transplant patients is described. They were treated with erythromycin and rifampicin, and all five survived. Two of them had rejected their grafts prior to their Legionella pneumonia; two rejected their transplants after reduction of immunosuppressive therapy to combat the infection. L pneumophila was present in the water distribution system of the hospital. Eradication measures included flushing the water pipes to the transplantation ward with hot and hyperchlorinated water, raising the warm water temperature to 60 degrees C, and installing ultraviolet (UV) irradiation units on the warm and cold water pipes to the ward. These measures were successful in that no new cases of legionellosis occurred after wards. L pneumophila could subsequently not be demonstrated by culture in plastic shower hoses supplied with UV-irradiated water. L pneumophila could be demonstrated by direct fluorescent antibody technique, but nonspecific reactions cannot be excluded. A higher prevalence of elevated L pneumophila antibody titers was observed in patients nursed for more than four weeks in the hospital than in patients with a shorter hospital stay, in hospital staff members, or in the general population. It seems that, with appropriate control measures, transplantation activities need not be discontinued in the presence of a minor cluster of Legionnaires' disease in renal transplant patients.

Neuropathological changes and neurological function after spinal cord compression in the rat.

As part of a series of experimental investigations of the effects of various pharmacological agents on the outcome of compressive spinal cord trauma in the rat, the time course of the cell changes in the cord at the site of and distal to the compression was studied at the light microscopic level. The degree of compression used with the present model results in a transient paraparesis that recovers almost completely over a period of 3 weeks as judged by the inclined plane technique. The most significant morphological findings were as follows. Initially (1 and 24 h after the impact) there was pronounced swelling and hemorrhage at the compression site, chiefly in the gray matter of the cord. On day 4 there was severe necrosis in the same region, with numerous macrophages and leukocytes. Rats killed after 21 days showed either minor residual signs of necrosis or essentially normal tissue architecture. Surprisingly, necrosis with delayed onset also developed in the dorsal columns, involving the pyramidal tracts. This necrosis was detected in animals killed after 9 and 21 days but not in those observed after 4 days or earlier. The longitudinal tracts of the white matter showed reduced staining in paraffin sections of the compression site. Epon sections revealed splits in the myelin sheaths and enlarged periaxonal spaces as early as 1 h after the impact. The alterations in the longitudinal tracts persisted throughout the 21-day observation period and extended down to L2-L4. There was gradual functional recovery, documented by the inclined plane test. Preinjury values were almost reached on day 21, although the cord still showed some morphological damage. In individual animals, no relation was found between degree of function as tested by inclined plane and extent of morphologic injury. Additional functional and morphological methods obviously are needed in future investigations of the effects of treatments on the outcome of compressive spinal cord injury.

Impact of handwashing on mortality in intensive care: examination of the evidence.

Our highest priority should be to increase compliance with hand hygiene guidelines. It is food for thought that in several studies the group with the lowest compliance in intensive care settings is intensive care physicians. It is a reasonable assumption that they are role models for the rest of the ICU staff. Studies on practical and efficient means to increase compliance with hand hygiene guidelines and to influence behavior surely are needed more than are elaborate and sophisticated studies on the effects of handwashing.

Changes of extracellular proteins in hippocampus during depolarization.

Local excitation of the hippocampus with N- methyl- d,l -aspartic acid caused a rapid release of specific proteins into the extracellular fluid. The proteins were recovered from the effluent of a small implanted tubing, permeable to macromolecules, and analyzed by sodium dodecyl sulphate electrophoresis.

A technique for simultaneous sampling of cerebrospinal and brain extracellular fluid in unanaesthetized rabbits.

The continuous sampling of cerebrospinal fluid (CSF) from unanaesthetized rabbits was combined with dialysis-perfusion of the hippocampus in order to simultaneously sample the extracellular fluid (ECF) and the CSF. Implantation of the CSF-drainage into the subarachnoid space caused a transient increase of blood cells and serum-derived proteins in the CSF. Essentially normal values were restored within 4 days. The subsequent implantation of a dialysis probe also induced an increase in CSF cells and proteins which returned to preoperative values within 2 days. The protein pattern of the ECF was dominated by proteins with isoelectric points of 4.4, 4.5, 4.6 and 5.0 and molecular weights of 14, 30 and 45 kDa. Bands with similar mobility were seen in CSF and serum, however at relatively lower concentrations, as compared to the total protein content.

Bacterial colonization and infection in an intensive care unit.

One hundred and one patients, nursed in an intensive care unit for at least 24 h, were monitored for bacterial colonization and infection. The infection rates were similar to those in other reports. Patients were not generally colonized with common environmental strains in the unit. Bacterial dissemination between patients was uncommon. No gentamicin resistant gram negative or Staphylococcus aureus strains were observed, nor methicillin resistant Staphylococcus aureus strains. The hypothesis that these favourable conditions are partly related to the excellent isolation and barrier nursing facilities in the unit cannot be fully substantiated.

Regulation of glutamate biosynthesis and release in vitro by low levels of ammonium ions.

The content and release of endogenous amino acids from isolated rat hippocampal slices were measured. The tissue was perfused with control media and pulsed with high potassium media in order to induce synaptic release. Pathophysiological concentrations of ammonium ions (3--5 mM) were added to the control medium for 60 min prior to the induced release. Amino acids belonging to the putative transmitter group were released extensively during potassium perfusion and, except for glutamate, even after ammonium ion perfusion. The spontaneous secretion of glutamate increased, however, slowly after the addition of ammonia. The incorporation of 14C from radiolabelled glucose and acetate into the amino acid fraction was studied in the presence of ammonia-containing media. Glucose was utilized to a moderately increasing extent, but acetate-derived radioactivity was strikingly decreased in the amino acid fraction during ammonia perfusion. The decreased acetate incorporation into amino acids was mainly due to an inhibition by ammonia of the accumulation of acetate by the CNS tissue.

Comparison of rat brain membrane antigens by complement mediated release of neurotransmitters from brain fractions using antisera against S-100 and Thy-1.

Synaptosomal, glial and neuronal fractions were prepared from rat brain and incubated to accumulate radioactively labelled neurotransmitters. Treatment of these fractions with antisera and complement showed that anti-(Thy-1) serum gave good release (50-75% of total uptake) of all neurotransmitters tested from synaptosomal and glial fractions. GABA and glutamate were released from neuronal perikarya, but not norepinephrine or serotonin. Anti-(S-100) serum gave no significant release of any neurotransmitter tested from any of the fractions, although all of them had previously been shown to contain this protein. These results are compatible with the membrane nature of Thy-1 and the mainly soluble nature of S-100 protein. They permit a selection for membrane antigens and neurotransmitters from different brain fractions. Antigenic differences between neuronal and glial plasma membranes were suggested by results with antiserum raised against bulk-isolated rat neuronal perikarya.

Microelectrode recordings from transected nerves in amputees with phantom limb pain.

Intraneural microelectrode recordings were made from the nerve supplying the phantom area in two patients suffering from phantom limb pain. Spontaneous activity was prominent in both cutaneous and muscle fascicle of the nerves. Tapping the neuromata which accentuated the phantom limb pain, induced afferent discharges with both short and long latencies, the latter from fibres with a conduction velocity of only 0.5 m/sec. Blocking the neuromata with lidocaine completely abolished the tap-induced afferent discharges and the tap-induced accentuation of the phantom pain. The spontaneous pain was, however, unchanged, as was the spontaneous activity recorded.

Expression of Ca(2+)-ion permeable alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptors in Xenopus oocytes injected with total RNA from human epileptic temporal lobe.

By using the Xenopus oocyte as an expression system, we have performed a series of experiments in order to examine the divalent cation-permeability of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptors from the human epileptic temporal lobe. Xenopus oocytes, injected with total RNA from the epileptic temporal lobe, were tested for expression of receptors by a conventional two electrode voltage-clamp technique. Administration of glutamate and AMPA gave small or no clear current responses, whereas kainate produced large inward non-desensitizing currents. The current responses evoked by kainate were concentration dependent. Experimental data gave a Hill coefficient of 1.06 and an EC50 value of 87 microM. The current to voltage relationship showed an inward rectification and when the concentration of divalent cations were enhanced, there was a shift in the reversal potential from -11 mV (2 mM Ca2+) to 12 mV (60 mM Ba2+). This yielded a pBa2+/pK+ permeability ratio of 1.6 when the constant field equation was used. The amplitude of the currents evoked by 600 microM kainate in solutions containing higher Ba(2+)-ion concentrations was markedly diminished (46% in 10 mM Ba(2+)- and 75% in 60 mM Ba(2+)-solution), when compared to those obtained in normal Ringer's solution, suggesting interactions between different cation species and/or screening of surface charges.

The role of hospital infection control in the quality system of hospitals.

Like other highly specialized fields, quality systems have their own vocabulary which we must be familiar with; it has been internationally standardized. This standard should be adhered to in order to avoid unnecessary ambiguities and confusion, and to facilitate exchange of information between disciplines. We, in the infection control field, are quality pioneers in hospitals. We have, within our discipline, created quality systems and practised quality surveillance for decades. This must be recognized. Medical quality audits intended for comparisons between hospitals, services and wards require measurable quality criteria and comparable measures for the presence of all relevant patient-related risk factors. To specify quality within our field we need much more detailed information on the effect and cost of infection control practices, as well as the costs of the infections we intend to control. To progress one step further, patients or their representatives, politicians, need to express what monetary value should be put on health, namely freedom from infection and its consequences.

Disinfection in bed-pan washers.

The degree of bacterial contamination on naturally soiled bed-pans, wash-bowls and urinals in an orthopaedic surgery ward has been studied before and after treatment in automated bed-pan washers with the water temperature in the final rinse above 85 degrees C and below 70 degrees C. In the machines studied, the degree of remaining contamination after treatment with a low-temperature final rinse was considered to be unacceptably high, probably due to an insufficient cleaning effect. In spite of this insufficient cleaning effect, after treatment with the water temperature in the final rinse above 85 degrees C the remaining bacterial contamination was less than one colony-forming unit per square centimetre in bed-pans and wash-bowls and less than 50 microorganisms per urinal. This is considered to be far below an acceptable upper limit.