Effect of phosphate or magnesium cathartics on serum calcium: observations in normocalcemic patients.

The administration of commercial phosphate cathartic in conventional doses to normal subjects prior to barium enema resulted in a striking increase in serum phosphorus levels followed by a decline in serum calcium levels in all subjects. Changes were highly significant (P less than .01) when compared with control subjects who were prepared for the same procedure with magnesium citrate. Levels of serum potassium also decreased significantly (P less than .01) but not serum sodium, chloride, bicarbonate, or magnesium.

Trigeminal alveolar nerve of the lower jaw in the cichlid Tilapia mariae: evidence for continual axon generation and presence of exceptionally small myelinated axons.

Cross sections from the trigeminal alveolar nerve of the lower jaw in the cichlid Tilapia mariae were examined by electron microscopy. The nerve fibers are arranged in groups with a core of unmyelinated and small myelinated axons, surrounded by myelinated axons of varying sizes. The core contains large bundles of unmyelinated axons collectively ensheathed by circumferentially located Schwann cells, as well as smaller bundles of unmyelinated axons partly separated from each other by Schwann cell processes. Among the unmyelinated axons, occasional scattered profiles resembling growth cones are seen. The total number of axons in this tooth-related nerve increases from approximately 1,500 to 5,000, as the animals grow in length from 4.5 to 21.5 cm. Some 24-49% of the axons are unmyelinated. The myelinated axons have maximum diameters of 1.0-3.0 micron, depending on body size. Most myelinated axons have diameters less than 1.0 micron and the smallest ones reach down to 0.3 micron. These results show that there is a continual addition of axons to the alveolar nerve of the lower jaw in Tilapia mariae and that the critical diameter for myelination in this peripheral nerve is similar to that typically found in the mammalian CNS.

Cerebral perfusion during nonpulsatile cardiopulmonary bypass.

The recording of middle cerebral artery (MCA) flow velocity by the transcranial Doppler method offers a new, noninvasive, continuous technique for studies of cerebral circulation. Comparative studies of electromagnetic internal carotid artery (ICA) flowmetry and MCA flow velocity by the transcranial Doppler technique have demonstrated that observed changes in MCA flow velocities reflect concomitant changes in cerebral circulation. Eleven high-risk patients undergoing cardiopulmonary bypass (CPB) procedures were included in a pilot study. Arterial blood pressure (BP), central venous pressure, and epidural intracranial pressure (EDP) were recorded during CPB. Cerebral electrical activity was recorded by a cerebral function monitor. Flow velocity in the MCA was increased during nonpulsatile CPB in 10 of the 11 patients. This increase was related to the degree of hemodilution, and the flow velocity during steady-state CPB was 80 to 300% of the prebypass value. The MCA flow velocity changed, however, in a pressure-passive manner with the cerebral perfusion pressure (CPP = BP - EDP) in the individual patient, which indicates that cerebral autoregulation was not operative. During the first 15 minutes after termination of bypass, the MCA flow velocity was reduced, but remained higher than the prebypass level, 110 to 210% of the level during the last 5 minutes preceding CPB.

Some observations on cerebral perfusion during cardiopulmonary bypass.

Blood flow was recorded with an electromagnetic flow probe on one internal carotid artery (ICA) during cardiopulmonary bypass (CPB) in 5 patients. The ICA flow was monitored continuously along with arterial blood pressure, epidural intracranial pressure, and cerebral electrical activity using a cerebral function monitor (3 patients). The ICA flow increased by 50 to 100% at the inception of extracorporeal circulation. This rapid enhancement of flow occurred within a thirty-second period and was due to rapid arterial hemodilution caused by introduction of the priming solution. A transitory fall in ICA flow was observed during subsequent minutes when the well-recognized drop in blood pressure took place and the cerebral perfusion pressure (CPP = blood pressure - epidural intracranial pressure) was reduced to less than 30 mm Hg. In only one instance, however, when CPP fell to 15 mm Hg, was the fall in flow lower than the prebypass level. Throughout the rest of CPB, with steady-state hemodilution and CPP levels in the range of 30 to 50 mm Hg, ICA flow was markedly enhanced (50 to 100% above the prebypass level). The flow pattern, however, disclosed a pressure-passive system, indicating that cerebral autoregulation was impaired or that the CPP levels were lower than the individual lower limit of cerebral autoregulation during the period of steady-state hemodilution on CPB. A transient depression of cerebral electrical activity was seen in 2 patients shortly after the introduction of CPB. This phenomenon is suggestive of qualitatively insufficient perfusion and was observed even when ICA bulk flow was increased (hematocrit values, 13 to 17%).

Odontogenic keratocysts. A follow-up study of 29 cases.

This study reports the incidence and recurrence rate of odontogenic keratocysts in a series of 531 jaw cysts treated at the Department of Oral Surgery, Karolinska Institute, Stockholm, from 1977 to 1984. Each case of a histologically verified odontogenic keratocyst was analysed and registered with respect to patient's age and sex, type of cyst, location and rate of recurrence. Twenty-nine odontogenic keratocysts were found (5.4% of all cysts). The most frequent locations were in the mandibular angle, ramus and third molar regions. During the observation period (1-8 years) 7 keratocysts (24%) recurred. These findings support previous observations.

Candidates' evaluation of psychoanalytic supervision.

The origins, methods, results, and discussions of a project undertaken by the advanced candidates at the Denver Institute for Psychoanalysis have been described. This project was designed to examine the supervisory process and to compile a consensual critique of individual supervisors from the candidate's point of view. We have included vignettes of supervisory experiences. It became our purpose to: (1) Develop a set of criteria by which the strengths and weaknesses of supervisors can be evaluated, (2) Involve the candidate in assessing his own learning needs, (3) Promote the objective assignment of supervisors, an assignment determined by the patient's problems, the candidate's learning needs, and the supervisor's varying capacities and abilities to effectively understand these problems and deal with these needs, (4) Expand the supervisory process to include what we felt were often unconscious or hiterto unacceptable issues, such as the function and use of countertransference, and the detection and open discussion of transference dilemmas between analyst and both patient and supervisor, (5) Stimulate dialogue at all levels of psychoanalytic education on the patient-analyst-supervisor relational system.

[Clinical experience and results of using the V.A.C. instill therapy in infected hip- and knee prosthetics]. / Klinische Erfahrungen und Ergebnisse über die Anwendung der V.A.C.-Instill bei infizierten Hüft- und Kniegelenksprothesen.

Since September 2005 our patients with acute endoprosthetic infection are treated, next to the normal wound debridement, with a full automatic vacuum drain system (V.A.C. instill system). This therapy unit entail a three step program. Based on the well known vacuum therapy, the new system contains an additional fluid drain and affecting period with an antibiotic or antiseptic instillation therapy. In the last half year we were able to treat five patients with endoprosthetic infection by using this therapy unit. In our opinion, we have a successfull method of treating patients with acute, infected big joints after endoprosthetic implantation. The therapy unit of V.A.C. instill is quickly available and easy to learn. Next to much better comfort for the patients the most advantage is to leave the prosthetic inside during the infection management with the new therapy unit. Further results in treating acute joint infections after endoprosthetic implantation must been shown, if this new method is to be the new standard in daily clinical routine.

[Cervical disk defects. Results of surgical treatment of cervical vertebral radiculopathy]. / Cervikale skivedefekter. Resultater ved operativ behandling av cervikal vertebrogen radikulopati.

The article presents a retrospective study of a series of 213 patients treated for cervical spondylotic radiculopathy by anterior surgery. The follow-up period ranged from 2-8 years. The overall functional outcome of surgery showed a rate of improvement of 91.5% at late follow-up. In 8.5% of the patients there was no change, and none considered themselves as being worse than before surgery. The various selective symptoms and signs were analyzed. Improvement of root pain was obtained in 93.4% of the patients, of sensory deficits in 90.7% and of motor deficits in 81.8%. The rate of improvement for neck pain was 44.6%. In this series, mortality was zero and there was no peroperative neurological deterioration. 3.3% of the patients were re-operated at the previous level. A second operation at another level or levels was necessary in 5.2% of the patients. Early surgical treatment, and possibly the degree of neurological deficits, were the only factors found to influence overall functional recovery. In contrast to the overall results, and in spite of large individual variations, neither sensory nor motor deficits, nor root pain, were statistically influenced by degree of root deficits or duration of symptoms.

Effects of surgery on cervical spondylotic myelopathy.

The results of surgery for treatment of cervical spondylotic myelopathy (CSM) were assessed 3 months (early results) and 2-8 years (late results) postoperatively in 99 patients. Extensive laminectomy as well as anterior decompression and fusion, or the two procedures at staged intervals, were used. Immediate postoperative deterioration was never seen after laminectomy performed under local anaesthesia (84 patients), while transient deterioration occurred after anterior surgery in 2 of 28 patients. Cervical spondylotic radiculopathy (CSR) was found in 73% of the patients. Operative treatment for CSM also improved root symptoms, anterior surgery to a larger extent than posterior decompression. Only 10% of the patients treated with extensive laminectomy needed a second anterior operation for radiculopathy. The progression of myelopathy was arrested in 95% of the patients after surgery. Improvement was obtained in 80% both in the early and late follow-up review when compared to the preoperative functional status. The evaluation disclosed a tendency of rapid improvement during the first 3 months, subsequently followed by slow improvement in 50% and slight deterioration in 15% of the patients. The degree of improvement was in many patients not sufficient to raise the functional capability to a higher level in the employed grading system. In our opinion it is therefore important to operate patients with CSM as early as possible before neurological deficits are too pronounced.

Effects of carotid endarterectomy on blood flow in the internal carotid artery.

A retrospective study of patients operated upon for carotid stenosis was undertaken with special emphasis on the internal carotid artery (ICA) blood flow. A total of 212 endarterectomies were performed in 198 patients. The overall operative mortality was 1.4%, and the cerebral morbidity was 2.8%. A temporary inlying shunt was used routinely during endarterectomy. In two of 198 endarterectomies the shunt itself could not be excluded as a possible cause of postoperative neurological deficits. The ICA blood flow before and after endarterectomy was determined by electromagnetic flowmetry in 160 operations. Flow measurements were compared in TIA and stroke patients, in patients with high and low degrees of luminal constriction, and in patients with occluded or "open" (minimal stenosis) contralateral ICA. The results indicate that the preoperative blood flow, as well as the increase in blood flow after removal of the stenosis, is determined not only by the degree of luminal constriction, but also by the magnitude of blood flow from all precerebral feeding arteries and their intracranial collateral circulation. In treatment of carotid stenosis critical evaluation of symptoms, angiography, and haemodynamics are essential. Endarterectomy is beneficial because an embolic source is removed, and probably because perfusion is improved to areas of the brain with marginal circulation. The main factors regulating the normal cerebral perfusion are cardiac output (mean perfusion pressure), arterial pCO2 and PO2, haematocrit, and the arterial and venous blood pressures. Comparatively few investigations have been published on the effect of endarterectomy upon internal carotid artery (ICA) blood flow 4, 12, 14, 27. Since 1970 we have routinely measured the ICA blood flow before and after endarterectomy. This paper reviews the clinical and haemodynamic results of our patients operated on for carotid stenosis.

[Thoracolumbar injuries. Surgical treatment of patients with neurological damage]. / Torakolumbale skader. Kirurgisk behandling av pasienter med neurologiske utfall.

This article presents the neurological outcome after surgery of a series of 54 patients with damage to the spinal cord and/or cauda equina caused by thoracolumbar injuries. The fractures, dislocations or fracture-dislocations were all reduced and stabilized by a Harrington distraction device or transpedicular fixation system (posterior segment fixator). Peroperative inspection revealed that correction and distraction alone may be inadequate to achieve intraspinal decompression. Additional anterior decompression by posterolateral approach was necessary in 31 patients (57%). In this series there was an unexpected high rate of dural rents. Tears were found in 11 patients (20%) and nerve roots (cauda equina) appeared to have herniated through the tear in eight. Significant improvement of the neurological deficits was obtained in 81%. The improvement rate was much better in patients with incomplete lesions than among those with complete lesions. We are convinced that surgery improves the neurological outcome if carried out at the proper time, after sufficient decompression of the spinal cord and nerve roots, and repair of dural rents.

Neurological outcome after surgery for thoracic and lumbar spine injuries.

New techniques for internal fixation, employed by neurosurgeons and orthopaedic surgeons, provide reduction and stabilization with early mobilization of patients after injuries of the thoracolumbar spine. It has, however, appeared difficult to prove that the neurological outcome after surgery may be superior to conservative treatment. In this study the neurological results after surgery are evaluated in 30 patients with injuries of the spinal cord and/or cauda equina. Canal encroachment was found on tomograms or CT in all patients. The unstable fractures, dislocations or fracture-dislocations were all reduced and stabilized by the Harrington distraction device. However, peroperative inspection revealed that the Harrington instrumentation alone may be inadequate in achieving intraspinal decompression. Additional anterior decompression by posterolateral approach was necessary in 13 of the 30 patients (43%). In this series there was an unexpectedly high rate of dural tears. These were found in 8 patients (27%) and nerve roots (cauda equina) appeared to have herniated through the tear in 6 of the 8 patients. Significant improvement of the neurological deficit was obtained in 22 of the 30 patients (73%), and the improvement rate in patients with incomplete lesions of the spinal cord was 83% (25 of 30 patients). In this series there was a definite trend toward greater neurological recovery when compared to the results obtained in patients treated conservatively. The importance of a neurosurgical approach in diagnosis and treatment of these patients is stressed.

The correlation of myelographic root sleeve deformity, uncovertebral spondylosis and radiculopathy.

Myelographic root sleeve deformities, uncovertebral spondylosis and myelopathy were correlated in 56 patients. Good correlation between root sleeve deformities and uncovertebral spondylosis was found. However, in some cases with spinal canal stenosis root sleeve deformities were found without corresponding bone changes. The correlation of radiculopathy to root sleeve deformity and uncovertebral spondylosis was 61 and 67%, respectively. Radiologic changes at an adjacent root level were often seen in patients without clinically correlated radiculopathy. The myelographic changes were verified at operation in all the 46 patients operated upon.

Late effect of bacteriophage T4D on the permeability barrier of Escherichia coli.

Cold centrifugation of lysis-inhibited Escherichia coli B infected with wild-type T4D results in extensive lysis beginning around 20 min after infection at 37 degrees C. Infection with an e mutant, which fails to make lysozyme, prevents lysis, but does not prevent a marked loss of K+ and Mg3+. The t gene product, thought to disrupt the cytoplasmic membrane in natural lysis, is not required for this handling-induced cation loss or lysis. Three lines of evidence argue that late protein synthesis is required to develop this potential for cation loss; the potential does not develop in infections by: (i) mutants defective in DNA synthesis, (ii) mutants defective in gene 55, and (iii) wild-type T4 when chloramphenicol is added at 6 min after infection. All late mutants examined, which are blocked in the major pathways of morphogenesis, do not prevent development of the potential. The evidence argues for a new, late effect of T4 infection on the cytoplasmic membrane.

das Mutation in bacteriophage T4D does not suppress an amber mutation in T4 gene 59.

Mutations termed das were isolated originally (Hercules and Wiberg, 1971) as partial suppressors of mutants in phage T4 genes 46 and 47. Since mutants in genes 46, 47, and 59 exhibit both an early arrest of phage DNA synthesis and the loss of this arrest in the presence of chloramphenicol or of mutations of T4 genes 33 and 55, we asked whether a das mutation can also suppress a gene 59 mutant. We find that it cannot--either at the level of phage production or DNA synthesis.

Membrane-associated DNase activity controlled by genes 46 and 47 of bacteriophage T4D and elevated DNase activity associated with the T4 das mutation.

Lethal, amber mutations in T4 genes 46 and 47 cause incomplete degradation of host DNA, premature arrest of phage DNA synthesis, accumulation of abnormal DNA replication intermediates, and defective recombination. These phenotypes can be explained by the hypothesis that genes 46 and 47 control a DNA exonuclease, but in vitro demonstration of such a nuclease has not yet been reported. Membrane and supernatant fractions from 46- and 47- mutant-infected and 46+ 47+ control-infected cells were assayed for the presence of the protein products of these genes (i.e., gp46 and gp47) and for the ability to degrade various DNA substrates to acid-soluble products in vitro. The two proteins were found only on membranes. The membrane fraction from 46- 47- mutant-infected cells digested native or heavily nicked Escherichia coli DNA to acid-soluble products three to four times slower that the membrane fraction from control-infected cells. No such effect was found in the cytoplasmic fractions. The effect on nuclease activity in membranes was the same whether 46- and 47- mutations were present singly or together. NaClO4, a chaotropic agent, released both gp46 and gp47 from 46+ 47+ membranes, as well as the DNase activity controlled by genes 46 and 47. DNA cellulose chromatography of proteins released from membranes by NaClO4 showed that gp46 and gp47 bound to the native DNAs of both E. coli and T4. Thus, the overall enrichment of gp46 and gp47 relative to total T4 protein was 600-fold (10-fold in membranes, 2-fold more upon release from membranes by NaClO4, and 30-fold more upon elution from DNA cellulose). T4 das mutations, which partially suppress the defective phenotype of 46- and 47- mutants, caused a considerable increase in vitro DNase activity in both membrane and cytoplasmic fractions, We obtained evidence that the das+ gene does not function to inhibit E. coli exonuclease I or V, endonuclease I, or the UV endonuclease of gene uvrA or to decrease the activity of T4 exonuclease A or the T4 gene 43 exonuclease.