Treatment of bone loss in proximal femurs of postmenopausal osteoporotic women with AGN1 local osteo-enhancement procedure (LOEP) increases hip bone mineral density and hip strength: a long-term prospective cohort study

This first-in-human study of AGN1 LOEP demonstrated that this minimally-invasive treatment durably increased aBMD in femurs of osteoporotic postmenopausal women. AGN1 resorption was coupled with new bone formation by 12 weeks and that new bone was maintained for at least 5-7 years resulting in substantially increased FEA-estimated femoral strength.

INTRODUCTION

This first-in-human study evaluated feasibility, safety, and in vivo response to treating proximal femurs of postmenopausal osteoporotic women with a minimally-invasive local osteo-enhancement procedure (LOEP) to inject a resorbable triphasic osteoconductive implant material (AGN1).

METHODS

This prospective cohort study enrolled 12 postmenopausal osteoporotic (femoral neck T-score ≤ - 2.5) women aged 56 to 89 years. AGN1 LOEP was performed on left femurs; right femurs were untreated controls. Subjects were followed-up for 5-7 years. Outcomes included adverse events, proximal femur areal bone mineral density (aBMD), AGN1 resorption, and replacement with bone by X-ray and CT, and finite element analysis (FEA) estimated hip strength.

RESULTS

Baseline treated and control femoral neck aBMD was equivalent. Treated femoral neck aBMD increased by 68 ± 22%, 59 ± 24%, and 58 ± 27% over control at 12 and 24 weeks and 5-7 years, respectively (p < 0.001, all time points). Using conservative assumptions, FEA-estimated femoral strength increased by 41%, 37%, and 22% at 12 and 24 weeks and 5-7 years, respectively (p < 0.01, all time points). Qualitative analysis of X-ray and CT scans demonstrated that AGN1 resorption and replacement with bone was nearly complete by 24 weeks. By 5-7 years, AGN1 appeared to be fully resorbed and replaced with bone integrated with surrounding trabecular and cortical bone. No procedure- or device-related serious adverse events (SAEs) occurred.

CONCLUSIONS

Treating femurs of postmenopausal osteoporotic women with AGN1 LOEP results in a rapid, durable increase in aBMD and femoral strength. These results support the use and further clinical study of this approach in osteoporotic patients at high risk of hip fracture.

Novel susceptibility locus at chromosome 6q16.3-22.31 in a family with GEFS+

BACKGROUND

Genetic epilepsy with febrile seizures plus (GEFS+) is a familial epilepsy syndrome with extremely variable expressivity. Mutations in 5 genes that raise susceptibility to GEFS+ have been discovered, but they account for only a small proportion of families.

METHODS

We identified a 4-generation family containing 15 affected individuals with a range of phenotypes in the GEFS+ spectrum, including febrile seizures, febrile seizures plus, epilepsy, and severe epilepsy with developmental delay. We performed a genome-wide linkage analysis using microsatellite markers and then saturated the potential linkage region identified by this screen with more markers. We evaluated the evidence for linkage using both model-based and model-free (posterior probability of linkage [PPL]) analyses. We sequenced 16 candidate genes and screened for copy number abnormalities in the minimal genetic region.

RESULTS

All 15 affected subjects and 1 obligate carrier shared a haplotype of markers at chromosome 6q16.3-22.31, an 18.1-megabase region flanked by markers D6S962 and D6S287. The maximum multipoint lod score in this region was 4.68. PPL analysis indicated an 89% probability of linkage. Sequencing of 16 candidate genes did not reveal a causative mutation. No deletions or duplications were identified.

CONCLUSIONS

We report a novel susceptibility locus for genetic epilepsy with febrile seizures plus at 6q16.3-22.31, in which there are no known genes associated with ion channels or neurotransmitter receptors. The identification of the responsible gene in this region is likely to lead to the discovery of novel mechanisms of febrile seizures and epilepsy.

Filamin A mutations cause periventricular heterotopia with Ehlers-Danlos syndrome

OBJECTIVE

To define the clinical, radiologic, and genetic features of periventricular heterotopia (PH) with Ehlers-Danlos syndrome (EDS).

METHODS

Exonic sequencing and single stranded conformational polymorphism (SSCP) analysis was performed on affected individuals. Linkage analysis using microsatellite markers on the X-chromosome was performed on a single pedigree. Western blotting evaluated for loss of filamin A (FLNA) protein and Southern blotting assessed for any potential chromosome rearrangement in this region.

RESULTS

The authors report two familial cases and nine additional sporadic cases of the EDS-variant form of PH, which is characterized by nodular brain heterotopia, joint hypermobility, and development of aortic dilatation in early adulthood. MRI typically demonstrated bilateral nodular PH, indistinguishable from PH due to FLNA mutations. Exonic sequencing or SSCP analyses of FLNA revealed a 2762 delG single base pair deletion in one affected female. Another affected female harbored a C116 single point mutation, resulting in an A39G change. A third affected female had a 4147 delG single base pair deletion. One pedigree with no detectable exonic mutation demonstrated positive linkage to the FLNA locus Xq28, an affected individual in this family also had no detectable FLNA protein, but no chromosomal rearrangement was detected.

CONCLUSION

These results suggest that the Ehlers-Danlos variant of periventricular heterotopia (PH), in part, represents an overlapping syndrome with X-linked dominant PH due to filamin A mutations.

Autosomal recessive form of periventricular heterotopia

BACKGROUND

Familial periventricular heterotopia (PH) represents a disorder of neuronal migration resulting in multiple gray matter nodules along the lateral ventricular walls. Prior studies have shown that mutations in the filamin A (FLNA) gene can cause PH through an X-linked dominant inheritance pattern.

OBJECTIVE

To classify cortical malformation syndromes associated with PH.

METHODS

Analyses using microsatellite markers directed toward genomic regions of FLNA and to a highly homologous autosomal gene, FLNB, were performed on two pedigrees to evaluate for linkage with either filamin gene.

RESULTS

Two consanguineous pedigrees with PH that suggest an autosomal recessive inheritance pattern are reported. MRI of the brain revealed periventricular nodules of cerebral gray matter intensity, typical for PH. Seizures or developmental delay appeared to be a common presenting feature. Microsatellite analysis suggested no linkage to FLNA or FLNB.

CONCLUSIONS

Autosomal recessive PH is another syndromic migrational disorder, distinct from X-linked dominant PH. Further classification of these different syndromes will provide an approach for genetic evaluation.

Increases in water potential gradient reduce xylem conductivity in whole plants. Evidence from a low-pressure conductivity method

A new method using hydrostatic suctions (less than 0.02 MPa) was used to measure whole-root conductivity (K(r)) in saplings of two angiosperm pioneer trees (Eucalyptus regnans and Toona australis) and two rainforest conifers (Dacrycarpus dacrydioides and Nageia fleurii). The resultant K(r) was combined with measurements of stem and leaf hydraulic conductivity to calculate whole-plant conductivity and to predict leaf water potential (Psi(l)) during transpiration. At normal soil temperatures there was good agreement between measured and predicted Psi(l) during transpiration in all species. Changes in the soil-to-leaf water potential gradient were produced by root chilling, and in three of the four species, changes in Psi(l) corresponded to those expected by the effect of increased water viscosity on K(r). In one species, however, root chilling produced severe plant wilting and a decline in Psi(l) significantly below the predicted value. In this species Psi(l) decreased to a value close to, or below, the Psi(l) at 50% xylem cavitation. It is concluded that decreased whole-plant conductivity in T. australis resulted from a decrease in xylem conductivity due to stress-induced cavitation.

Proton magnetic resonance spectroscopic imaging in children with recurrent primary brain tumors

PURPOSE

Proton magnetic resonance spectroscopic imaging ((1)H-MRSI) is a noninvasive technique for spatial characterization of biochemical markers in tissues. We measured the relative tumor concentrations of these biochemical markers in children with recurrent brain tumors and evaluated their potential prognostic significance.

PATIENTS AND METHODS

(1)H-MRSI was performed on 27 children with recurrent primary brain tumors referred to our institution for investigational drug trials. Diagnoses included high-grade glioma (n = 10), brainstem glioma (n = 7), medulloblastoma/peripheral neuroectodermal tumor (n = 6), ependymoma (n = 3), and pineal germinoma (n = 1). (1)H-MRSI was performed on 1. 5-T magnetic resonance imagers before treatment. The concentrations of choline (Cho) and N-acetyl-aspartate (NAA) in the tumor and normal brain were quantified using a multislice multivoxel method, and the maximum Cho:NAA ratio was determined for each patient's tumor.

RESULTS

The maximum Cho:NAA ratio ranged from 1.1 to 13.2 (median, 4.5); the Cho:NAA ratio in areas of normal-appearing brain tissue was less than 1.0. The maximum Cho:NAA ratio for each histologic subtype varied considerably; approximately equal numbers of patients within each tumor type had maximum Cho:NAA ratios above and below the median. Patients with a maximum Cho:NAA ratio greater than 4.5 had a median survival of 22 weeks, and all 13 patients died by 63 weeks. Patients with a Cho:NAA ratio less than or equal to 4.5 had a projected survival of more than 50% at 63 weeks. The difference was statistically significant (P =.0067, log-rank test).

CONCLUSION

The maximum tumor Cho:NAA ratio seems to be predictive of outcome in children with recurrent primary brain tumors and should be evaluated as a prognostic indicator in newly diagnosed childhood brain tumors.

The Phylogenetic Affinities of Nothofagus (Nothofagaceae) Leaf Fossils based on Combined Molecular and Morphological Data

The phylogenetic placements of leaf fossils of Nothofagus (Nothofagaceae) were determined using parsimony analyses of molecular and morphological data for extant species combined with morphological data for fossils. Placement was possible for only seven of the 30 or so described fossil species of Nothofagus because only these had sufficiently good preservation of both cuticular and leaf architectural characters. In combined analyses of morphology and molecular data, leaf cuticular characters showed little homoplasy. In contrast, many architectural characters, including some leaf margin and venation characters, showed high homoplasy, making it difficult or impossible to accurately determine the phylogenetic affinities of impression fossils of this genus.

Immunoisolation of adult porcine islets for the treatment of diabetes mellitus. The use of photopolymerizable polyethylene glycol in the conformal coating of mass-isolated porcine islets

Functional porcine islets, free of known pathogens, can serve as a source of insulin producing cells for the treatment of experimentally induced insulin dependent Diabetes Mellitus. Porcine islets can be conformally coated (microencapsulated) with a covalently linked, stable permselective membrane while maintaining islet viability and function. The PEG conformal coating is immunoprotective in a discordant xenograft animal model (porcine islets to rat).

Upper gastrointestinal tract and abdomen: water as an orally administered contrast agent for helical CT

PURPOSE

To evaluate the use of orally administered water as a negative contrast agent and intravenously administered glucagon in helical computed tomography (CT) of the upper abdomen.

MATERIALS AND METHODS

Ninety-eight adult patients underwent 102 helical CT examinations. Patients received 700 mL of water orally 30 minutes before and another 350 mL of water orally with 1 mg of glucagon intravenously just before CT. The amount of water actually ingested was recorded. Luminal distention at five sites was graded on a three-point scale; depiction of six normal anatomic structures was evaluated.

RESULTS

Luminal distention improved with the amount of water ingested in four of the five sites (P < .03 in three sites). Depiction of all six normal anatomic structures improved with increasing luminal distention (P < .001). The normal duodenal papilla was seen in 42% (83 of 198) of the examinations. Of 87 patients who had previously undergone CT with positive oral contrast agents, 89% (n = 77) preferred the water, 11% (n = 10) had no preference, and none preferred the positive agent (P < .001). Upper gastrointestinal tract abnormalities were easily recognized and depicted.

CONCLUSION

Water is an efficacious negative contrast agent for evaluation of the upper gastrointestinal tract during helical CT.

Ankle equinus. Prevalence and linkage to common foot pathology

One hundred seventy-six of 209 consecutive new patients were examined over a 6-week period for the presence or absence of equinus deformity in the course of their workup for their primary complaint. Of the patients examined, 96.5% exhibited restricted ankle dorsiflexion requiring compensation during gait. Foot complaints were categorized into medial, lateral, and rearfoot problems. The high incidence of equinus reflects "acquired deformity" related to factors of lifestyle that leave the posterior muscles at a physiologic disadvantage toward maintaining flexibility. There is a significant relation between compensation for ankle equinus and podiatric pathology. More attention should be directed at the evaluation of ankle range of motion during examination of common foot problems. Gastrosoleal stretching is an important treatment modality that can lead to a higher success rate of conservative treatment. It can decrease the need for foot surgery, and significantly reduce the number of failed or serial surgical procedures.

The X-Ray Surface Forces Apparatus: Structure of a Thin Smectic Liquid Crystal Film Under Confinement

An x-ray surface forces apparatus for simultaneously measuring forces and structures of confined complex fluids under static and flow conditions is described. This apparatus, combined with an intense synchrotron x-ray source, allows investigation of molecular orientations within a thin liquid crystal film confined between two shearing mica surfaces 3900 angstroms apart. The layer-forming smectic liquid crystal 8CB (4-cyano-4'-octylbiphenyl) adopted a series of distinct planar layer orientations, including the bulk flow-forbidden b orientation.

Induction of islet cytodifferentiation by fetal mesenchyme in adult pancreatic ductal epithelium

Recombinant tissue consisting of adult ductal epithelium isolated from pancreas and fetal mesenchyme was transplanted subcutaneously in the inguinal region of nude mice or epididymal fat pads of rats with a tissue chamber device for short-term (8-day) or long-term (6- to 12-wk) duration. We found that recombinant tissue underwent morphogenesis and cytodifferentiation, thereby forming islets that contained cells immunocytochemically positive for insulin and glucagon. Islet cytodifferentiation occurred in approximately 20% of the recombinants. In recombinants that developed into islets, the tissue was always in close association with an extracellular matrix, nerves, and blood vessels. Controls consisting of mesenchyme alone or duct epithelium alone showed no evidence of morphogenesis of cytodifferentiation. Pancreatic rudiments were also implanted to serve as positive controls. This is the first demonstration of islet cytodifferentiation from adult duct epithelium.

Engraftment after infusion of CD34+ marrow cells in patients with breast cancer or neuroblastoma

The CD34 antigen is expressed by 1% to 4% of human and baboon marrow cells, including virtually all hematopoietic progenitors detectable by in vitro assays. Previous work from our laboratory has shown that CD34+ marrow cells can engraft lethally irradiated baboons. Because the CD34 antigen has not been detected on most solid tumors, positive selection of CD34+ cells may be used to provide marrow cells capable of engraftment, but depleted of tumor cells. In seven patients with stage IV breast cancer and two patients with stage IV neuroblastoma, 2.5 to 17.5 x 10(9) marrow cells were separated by immunoadsorption with the anti-CD34 antibody 12-8 and 50 to 260 x 10(6) positively selected cells were recovered that were 64 +/- 16% (range 35% to 92%) CD34+. The patients received 1.0 to 5.2 x 10(6) CD34-enriched cells/kg after marrow ablative therapy. Six patients engrafted, achieving granulocyte counts of greater than 500/mm3 at 34 +/- 10 (range 21 to 47) days and platelets counts of greater than 20,000/mm3 at 46 +/- 14 (range 28 to 66) days posttransplant. Five of these patients showed durable engraftment until the time of death 82 to 386 days posttransplant. One patient failed to sustain engraftment associated with metastatic marrow disease. Three patients died at days 14, 14, and 17 posttransplant, two of whom had evidence of early engraftment. These studies suggest that CD34+ marrow cells are capable of reconstituting hematopoiesis in humans.

Current perception threshold in evaluating foot pain. Two case presentations

Two cases are reported in which patients presented with complaints of foot pain, and a clinical suspicion of radiculopathy was supported by current perception threshold testing. Chiropractic manipulation of the lumbar spine resulted in alleviation of the lower extremity symptoms. Current perception threshold testing is a valuable neurologic testing modality that is noninvasive, nonaversive, and highly reliable for evaluation of sensory nerves where neuropathy is suspected. This technology has been described for evaluation of diabetic neuropathy, uremic screening, and alcohol and chemical toxicity. Additionally, current perception threshold is useful for evaluation of other neuropathies, such as carpal tunnel syndrome and other entrapment neuropathies. The authors encourage further investigation of this modality in the diagnosis and evaluation of peripheral neuropathy and unexplained foot pain secondary to spinal nerve impingement.

Modification of the Kalish osteotomy to correct the proximal articular set angle

A preliminary report of a new bunion procedure is described. This new procedure provides a relative reduction of the intermetatarsal angle and corrects the proximal articular set angle, yet incorporates the principles of compressive rigid internal fixation. The procedure is best summarized as a combination of the Kalish modification of the Austin bunionectomy and the Green-Laird modification of the Reverdin bunionectomy.

Effect of rise in cAMP levels on Ca2+ influx through voltage-dependent Ca2+ channels in HIT cells. Second-messenger synarchy in beta-cells

With a glucose-responsive beta-cell line (HIT cells), we tested the hypothesis that the cytosolic free-Ca2+ level ([Ca2+]i) is an intracellular signal through which a rise in cyclic AMP (cAMP) levels is transmitted to potentiate glucose-stimulated insulin secretion. In these cells, glucose stimulates the acute release of insulin without increasing [Ca2+]i or altering cAMP content. Either forskolin or 3-isobutylmethylxanthine (IBMX) potentiated glucose-stimulated insulin secretion and increased cAMP levels. At either a submaximal glucose concentration or maximally stimulatory glucose concentration, both IBMX and forskolin triggered a rapid rise in [Ca2+]i (1.9- and 1.5-fold increase over basal levels, respectively). Similarly, glucagon stimulated a 1.3-fold increase in [Ca2+]i over basal levels. The effect on [Ca2+]i required glucose and was secondary to Ca2+ influx through voltage-dependent Ca2+ channels because it was blocked by either chelation of extracellular Ca2+ with EGTA or by the Ca2+-channel blockers verapamil and nimodipine. Verapamil also inhibited IBMX potentiation of glucose-stimulated insulin secretion and the IBMX-induced rise in [Ca2+]i in a dose-dependent manner with IC50s of 2 x 10(-5) and 4 x 10(-6) M, respectively. We conclude that in the beta-cell, a rise in cAMP levels increases Ca2+ influx through voltage-dependent Ca2+ channels and that this represents a mechanism by which cAMP potentiates glucose-stimulated insulin secretion in beta-cells.

Engraftment in 86 with patients lymphoid malignancy after autologous marrow transplantation

The kinetics of marrow engraftment was retrospectively analysed in 55 patients with malignant lymphoma (ML) and 31 patients with acute lymphoblastic leukemia (ALL) after marrow-ablative therapy followed by autologous bone marrow transplantation. Thirty-eight percent of patients with ML, most of whom were transplanted in relapse and 13% of patients with ALL, mostly transplanted in remission, showed failed or delayed engraftment. Analysis of the total patient group showed that failure to recover platelet counts was significantly correlated with detection of disease in the marrow early after transplantation (p less than 0.001). Platelet recovery was also correlated with survival (p = 0.0001), disease-free survival (p = 0.0001), and the probability of relapse (p = 0.02). In those patients achieving engraftment, multivariate regression analysis failed to reveal any single in vitro test of marrow nucleated cell or progenitor cell numbers that significantly influenced time to achieve recovery of either granulocyte or platelet counts.

The effect of heat shock on the morphology of amphibian lampbrush chromosomes

Isolated oocytes of Triturus cristatus carnifex cultured in Barthe's medium respond to a sudden increase in temperature of 35 or 37 degrees C by the rapid condensation of their lampbrush chromosomes. The degree of condensation depends on the severity of the heat shock and is accompanied by the retraction of the transcriptionally active lampbrush loops. The oocytes were kept at 20 degrees C for 12 h after the period of heat shock, before the chromosomes were isolated. The minimum period required to effect loop retraction in immature oocytes of 0.7 mm in diameter was 10 min at 35 degrees C; although more extensive and complete retraction occurred if the oocytes were incubated for periods of up to 40 min. Chromosomes from more mature oocytes (1.4 mm in diameter) require longer periods of heat shock before undergoing condensation. The oocytes themselves do not show any obvious morphological changes after heat shock, although the germinal vesicles are initially too fragile to isolate manually for several hours. When the oocytes are returned to ambient temperatures, they can be cultured in Barthe's medium for several days, enabling the chromosomes to be isolated and studied. Generally, the chromosomes and loops from immature oocytes remain in a condensed state for about 48 h but then the chromosomal axis begins to relax and the loops begin to re-form. Depending on the severity of the initial heat shock, complete recovery of the normal lampbrush morphology is attained after a few days. The re-formed loops are morphologically indistinguishable from untreated loops in control preparations and are of the same length on average. This response of lampbrushes to heat shock is a reliable and repeatable process and should therefore become a valuable model system for the study of chromatin and chromosome structure during changes in transcriptional activity. The time taken for the lampbrushes to recover their normal morphology, is discussed in terms of the return to normal cellular transcription.

Soft X-ray contact imaging of nucleolar chromatin using synchrotron radiation: a comparative scanning and transmission electron microscope study

Contact images (CI) of dehydrated, nucleolar chromatin from amphibian oocytes have been produced by soft X-rays from a synchrotron radiation source. These CI have been compared with the morphology of the original chromatin as seen in scanning and transmission electron microscopes. The quality and informational content of the CI depend very much on certain preparative procedures. The following factors have a marked effect on image quality and need to be carefully controlled: the total X-ray dose, the time and nature of development and the distance of the specimen from the photoresist. The preparation of the chromatin itself, providing that it is critically point dried, is less important. By following a regime of high X-ray dose, sufficient for penetration of the rather thick chromatin rings, and gentle development so that fine detail is not dissolved from the resist surface, it has been possible to obtain images which closely resemble the original chromatin, although the detailed resolution of the CI is not as clear. The smallest biological structures clearly resolved in the CI are ribonucleoprotein granules, which vary in size from 200 to 800 nm. However, by further refinement of preparative conditions it should be possible to improve on the informational content of these images.

Airway complications from laryngoscopy and panendoscopy

Laryngoscopy and panendoscopy can cause airway complications. To determine the risk to the airway from reintubation following general anesthesia in otolaryngology patients, we examined recovery room and anesthesia records at the Albany Veterans Administration Medical Center covering a 10-year period. From this information we determined the incidence of recovery room reintubation and studied airway risk factors associated with otolaryngologic endoscopy. From 1975 to 1984, 10,060 surgical patients were intubated at the Albany VA Medical Center. Only 17 patients (0.17%) required reintubation. Of 1,365 otolaryngology patients intubated during the same period, 324 had laryngoscopy and 302 had panendoscopy. Significantly, four laryngoscopy patients (1.2%) and nine panendoscopy patients (3%) required recovery room intubation. Nine endoscopy patients needed reintubation within 1 hour of extubation. We conclude that the risk of postoperative airway compromise is significantly greater among patients who underwent diagnostic laryngoscopy and panendoscopy than among patients who had general anesthesia for other reasons.

Venocclusive disease of the liver after chemoradiotherapy and autologous bone marrow transplantation

We determined the incidence of venocclusive disease of the liver (VOD) in 96 recipients of autologous bone marrow transplants (BMT) to be 9.4%, a figure less than that reported for allogeneic transplantation. The development of VOD was compared in a cohort of 21 autologous BMT recipients and in 56 randomly chosen, comparably conditioned, concurrent allogeneic BMT recipients. One of these 21 (4.8%) autologous recipients developed VOD, versus 14 of 56 (25%) allogeneic recipients (P less than 0.05). Logistic regression analysis confirmed pretransplant hepatocellular dysfunction as a risk factor for VOD, and suggested that the use of methotrexate and/or cyclosporine contributes to the development of VOD after chemoradiation therapy. However, a graft-versus-host reaction cannot be excluded as a cause of the higher incidence of VOD in allogeneic recipients.

Allogeneic and syngeneic marrow transplantation following high dose dimethylbusulfan, cyclophosphamide and total body irradiation

Fifty-eight patients received an allogeneic or syngeneic marrow transplant following conditioning with high doses of dimethylbusulfan (DMB), cyclophosphamide (CY) and total body irradiation (TBI). Thirty-two patients had either chronic myeloid leukemia (CML) in accelerated phase or blast transformation, or acute leukemia after first relapse. The actuarial survival of these 32 patients at 3 years was 12% compared with 25% for a group of 206 patients with similar diagnoses prepared for transplantation with CY and TBI alone. This reduced survival was associated with a greater incidence of early non-leukemic deaths, in particular as a result of severe hepatic veno-occlusive disease. The incidence of leukemic relapse was not different in the two groups. Of 13 patients with CML in chronic phase who received syngeneic transplants following DMB, CY and TBI, nine are alive in hematologic and cytogenetic remission from 3.9 to 9.4 (median 6.2) years post-transplant.

Increase in cAMP levels in beta-cell line potentiates insulin secretion without altering cytosolic free-calcium concentration

With an SV40-transformed hamster beta-cell line (HIT cells) as a model system, we tested the hypothesis that a rise in cAMP levels potentiates insulin release by an effect on the cytosolic free-Ca2+ concentration ([Ca2+]i). Intracellular cAMP levels were measured by radioimmunoassay, and [Ca2+]i was monitored with the fluorescent Ca2+ indicator quin 2. Insulin secretion was followed in static incubations or perifusion of the cells. In perifusion, both high glucose and depolarization of the beta-cell with 40 mM K+ trigger a monophasic pattern of insulin release without altering the HIT cell cAMP content. Addition of either the phosphodiesterase inhibitor isobutylmethylxanthine (IBMX) or the adenylate cyclase activator forskolin dramatically increased the cellular cAMP content, potentiated the burst phase of insulin release, and coupled the immediate phase of insulin secretion to a sustained secretory response. However, increases in cellular cAMP content were not associated with a change in [Ca2+]i. Thus, the potentiation of insulin secretion by a rise in cAMP in the HIT cell is not mediated by a release of stored Ca2+. Either a glucose-generated signal or a rise in [Ca2+]i triggered by high K+ can synergize with a rise in cAMP to couple the burst or immediate release of insulin evoked by either secretagogue to the sustained release of insulin.

Controlled rate freezing of human marrow in a constant temperature cooling gradient in air

A new instrument which utilizes a computer controlled freezing platform moving in a constant air temperature gradient generated over liquid nitrogen (LN2) was evaluated for cryopreservation of human marrow. Marrows were placed horizontally on the freezing platform which was suspended over LN2 in a cylindrical freezing chamber. The platform was raised or lowered to maintain a predetermined fixed cooling rate in response to temperature monitored and recorded by the computer from a thermocouple placed at platform level. Separate freezing programs were created for different marrow volumes. The viability of normal marrow was tested in vitro before and after freezing. Recovery of marrow cells after freezing and thawing, as measured by cell counts and CFU-GM assays, were the same for the constant air gradient instrument as for a conventional freezing instrument. Thirteen patients received autologous marrow transplants utilizing marrow cryopreserved in the constant air gradient instrument and engraftment results were indistinguishable from those obtained for marrow cryopreserved with a conventional instrument.

The occurrence of lampbrush chromosomes in early diplotene oocytes of Xenopus laevis

Transmission electron microscopy has been used to study the chromosomes found in the early diplotene oocytes of Xenopus laevis. Chromosomes from 40 micron early diplotene oocytes were found to possess a normal lampbrush chromosome morphology. The contour length of the loops found on these chromosomes was measured, the mean value determined and compared with that for lampbrush chromosomes found on 300 micron mid-diplotene (Dumont stage II) oocytes. The mean contour length of the loops from 40 micron oocytes (12.33 +/− 6.5 micron) was longer than that for the 300 micron oocytes (7.897 +/− 5.22 micron). Analysis of variance showed these two values to be significantly different (P less than 0.01). The mean loop density (number of loops per 25 micron chromosome axis) was also determined for the two size classes of oocytes, being 9.33 +/− 2.05 per 25 micron of chromosome axis for the 40 micron size class and 11.2 +/− 2.435 per 25 micron of chromosome axis for the 300 micron size class. Analysis of variance showed these values to be significantly different (P less than 0.01). The results of the present study demonstrate that the lampbrush chromosomes found in 40 micron early diplotene oocytes possess a greater loop contour length and a lower density of loops than those found in 300 micron, mid-diplotene oocytes. Possible reasons for these observations are discussed.

Mixed hematologic chimerism after allogeneic marrow transplantation for severe aplastic anemia is associated with a higher risk of graft rejection and a lessened incidence of acute graft-versus-host disease

Ninety-six patients with severe aplastic anemia who received a sex-mismatched, HLA-identical allogeneic sibling marrow transplant had sequential cytogenetic analyses performed to determine the incidence and implications of posttransplant mixed hematologic chimerism. Of the 96 patients, 56 (58.3%) became mixed chimeras with coexisting host and donor cells detected in peripheral blood or marrow 14 days or later after transplant, and 40 patients (41.7%) were complete chimeras with 100% donor-type hematopoietic cells. The incidence of mixed chimerism was independent of prior blood production transfusions and infusion of donor buffy coat. The rejection rate was significantly increased in the mixed chimeric group, particularly in patients not receiving buffy coat (14 of 36 rejecting), although overall, the majority (69.7%) retained their first graft. Rejection was seen almost exclusively in patients exposed to multiple transfusions before transplantation. If patients who reject their first graft are censored, the overall incidence of grades II through IV acute graft-v-host disease (GVHD) was significantly reduced in those with mixed chimerism. Transfused patients with mixed chimerism in particular were less likely to develop grades II through IV acute GVHD. The incidence of chronic GVHD was similar in the two groups and did not significantly influence survival. In this study, mixed chimerism persisted for up to 395 days posttransplant, either the first graft being rejected or, more commonly, hematopoiesis reverting to 100% donor-type cells. Mixed lymphohematopoietic chimerism may persist in patients with aplastic anemia who have received matched allogeneic marrow transplants for significant periods before hematopoiesis reverts to donor cell type.

Surface charge and hydrophobic properties of fresh and cryopreserved blood phagocytes as determined by partition in two-phase aqueous polymer systems

Cell partitioning in two-phase aqueous polymer systems was used to examine hydrophobic and surface charge-related membrane properties of fresh and cryopreserved human blood phagocytes. This technique is highly sensitive to cell surface characteristics, and the partition behavior depends exponentially on the membrane properties involved. The transition from fresh to cryopreserved and reconstituted cells was accompanied by a significant loss of net negative charge without detectable alteration in hydrophobic membrane properties as detected by the partition technique. The partition coefficient (PC), which is the proportion of cells partitioning into the upper phase, when measured for fresh cells mixed with dimethyl sulfoxide (Me2SO) and cryopreserved leukocytes. No difference was detected between the PCs of the total leukocytes and phagocytes as determined by differential leukocyte counts of the upper polymer phase. The significantly reduced PC of cells prepared by dextran (Dx) separation in both charge-sensitive and -insensitive systems is attributable to the capacity of Dx to adsorb, in part irreversibly, to cells so that those carrying Dx tend to partition with Dx in the lower phase. These results serve to illustrate the utility of partitioning as a highly sensitive method to probe leukocyte surface membrane properties.

Calcium dependency and free calcium concentrations during insulin secretion in a hamster beta cell line

Using a glucose-responsive beta cell line, we tested the hypothesis that the free cytosolic Ca2+ concentration ([Ca2+]i) is the primary signal that couples a stimulus to insulin secretion, and examined the involvement of the extracellular Ca2+ pool in this process. Glucose or depolarization of the beta cell with 40 mM K+ stimulated a monophasic release of insulin directly proportional to the extracellular Ca2+ concentration. 40 mM K+ increased 45Ca2+ uptake and increased [Ca2+]i, which was measured with quin 2, 4.7-fold, from 56 +/- 3 to 238 +/- 17 nM. With high glucose, 45Ca2+ uptake did not increase, and [Ca2+]i was unchanged or fell slightly. There was a striking correlation between inhibitory effects of verapamil, the Ca2+ channel blocker, on insulin secretion and the rise in [Ca2+]i evoked by K+. Higher concentrations of verapamil were required to inhibit glucose- than K+-stimulated insulin secretion (dose giving half-maximal effect of 1.4 X 10(-4) M vs. 6.0 X 10(-7) M). Incubation in Ca2+-free, 1 mM EGTA buffer for 30 min lowered [Ca2+]i to 14 +/- 2 nM, and inhibited acute insulin release to both secretagogues. If high glucose was present in the Ca2+-free period, reintroduction of 2.5 mM Ca2+ in high glucose restored insulin secretion only to the basal rate. However, if low glucose was present during the Ca2+-free period, high glucose and 2.5 mM Ca2+ triggered a full first-phase insulin response. These data suggest that high glucose generates a non-Ca2+ signal that turns over rapidly and provide direct evidence that K+ triggers insulin release by drawing extracellular Ca2+ into the beta cell through verapamil-sensitive Ca2+ channels. However, an increase [Ca2+]i is not the primary signal that evokes glucose-stimulated insulin release in this beta cell line.

Allogeneic bone marrow transplantation for Philadelphia-chromosome positive acute lymphoblastic leukemia

Allogeneic bone marrow transplantation (BMT) produced remission in three patients with Philadelphia-chromosome (Ph1)-positive acute lymphoblastic leukemia (ALL) in relapse. Two patients had remissions which lasted longer than two years. Since the prognosis of Ph1-positive ALL treated with conventional therapy is poor, BMT is indicated in first remission in this disease.

Marrow harvesting for autologous marrow transplantation

The results and complications of 224 marrow collections from 200 patients with malignant disease who underwent marrow aspiration and storage for subsequent autologous marrow transplantation (AMT) were analyzed. The median age of the patients was 35 years (range 1-68); 131 patients had hematologic malignancies and 69 had solid tumors. Thirty-one patients proceeded directly to AMT after marrow aspiration at a median of 4.5 days (range 0-10). A further 75 patients received AMT a median of 3.0 months (12 days-10 years) after marrow aspiration. The remaining 94 patients had marrow stored but not infused. When a second aspiration was performed from the same patient within seven weeks, the yield of marrow nucleated cells was significantly reduced (p less than 0.02). A negative linear correlation was observed between CFU-C/kg harvested and the day to achieve a posttransplant blood neutrophil count greater than 500/cmm (r = -0.3092, p less than 0.05). A total of 36 (17.4%) complications associated with marrow aspiration were observed including two (0.97%) life-threatening episodes. Postoperative fever accounted for 23 of 34 episodes of minor complications. There was no increased risk of serious complications with decreased time from aspiration to transplant. It was concluded that the morbidity and mortality from autologous marrow aspiration did not differ significantly from that observed in normal donors.

Bronchiolitis obliterans complicating bone marrow transplantation

A 19-year-old woman with extensive, persistent chronic graft versus host disease (GVHD), following an HLA-identical bone marrow graft for acute leukemia, developed rapidly progressive airflow obstruction 140 days post-transplantation (PT) and presented clinically with persistent cough, inspiratory rales, bronchospasm and exertional dyspnea. Pulmonary function tests (PFT) showed rapidly evolving severe airflow obstruction and hypoxemia without restrictive ventilatory defect. Open lung biopsy on the 204th day PT confirmed focal bronchiolitis obliterans. On the 381st day PT, she remained clinically stable. Chest x-ray film showed mild overinflation, but was otherwise unremarkable. PFT's continued to show very severe airflow obstruction without restrictive ventilatory defect. The etiology of the obliterative bronchiolitis might be explained on the basis of a direct immunologic reaction mediated by GVHD or possibly a joint viral-GVHD interaction. Awareness and further detailed documentation and analysis of this unusual respiratory syndrome associated with marrow transplant recipients may help clarify the role of GVHD in the development of lung disease in recipients of marrow grafts.

Perifusion of a clonal cell line of Simian virus 40-transformed beta cells. Insulin secretory dynamics in response to glucose, 3-isobutyl-1-methylxanthine, and potassium

A perifusion system for the study of insulin secretory dynamics of a clonal, Simian virus 40-transformed hamster pancreatic beta cell line (HIT cells) is described. After a change from glucose-free to higher glucose levels in the perifusate, insulin secretion increased rapidly in a dose-dependent manner. The pattern of glucose-stimulated insulin release was monophasic and was not sustained during a continued glucose stimulus. Perifusing the cells with low glucose (0.3 mg/ml) before a glucose stimulus of 3.5 mg/ml resulted in more rapid insulin release with lower peak secretory rates than those seen after a glucose-free period. The combined stimulus of high glucose and 100 microM 3-isobutyl-1-methylxanthine (IBMX), a phosphodiesterase inhibitor, significantly enhanced the acute insulin secretory response and also resulted in a biphasic secretory pattern that was sustained throughout the 60-min stimulation period. Insulin secretion stimulated by IBMX required a nonstimulatory level of glucose in the perifusing media, and, if this requirement was met, the immediate release of insulin was similar to that evoked by high glucose alone. High potassium (40 mM) also triggered a monophasic release of insulin. These studies demonstrate that glucose or high K+, which depolarizes the plasma membrane, and IBMX, an agent presumed to increase intracellular cyclic AMP levels, can signal the acute release of insulin from these beta cells. This cell line is a unique model system for studying the mechanism of insulin secretion.

Differential effects of microtubule-altering agents on beta-cells during development

The effect of microtubule-altering agents on the insulin secretory response to glucose during the perinatal period was investigated with an in vitro perifusion system. Rat pancreatic mince from day 17 of gestation (D17G) to day 6 postnatally (D6PN) were perifused for 60 min in basal glucose followed by 45 min with high glucose (3.5 mg/ml) or with high glucose plus 10 mM arginine (D17G). The two phases of insulin secretion in response to high glucose developed in an age-dependent and asynchronous manner. The first phase matured between D17G and D18G, and maturation of the second phase occurred subsequently. Vinblastine (VB) (20 or 100 microM) had a differential effect on the insulin secretory response. VB did not inhibit stimulated insulin release at D17G. This absence of an inhibitory effect of VB at D17G could not be explained by the absence of polymerized tubulin because microtubules were present in the control beta-cells and, in addition, VB treatment resulted in the formation of paracrystalline deposits. Subsequently in development, and with isolated islets of the adult, VB inhibited stimulated insulin release. Heavy water (deuterium oxide, D2O) inhibited stimulated insulin secretion at D17G but blocked completely insulin release from the near-term beta-cell. The inhibition of insulin secretion by D2O was rapidly reversed when water replaced D2O in the perifusion media. The results indicate that the maturation of the second phase of insulin secretion coincides with the ability of the microtubule-altering agents to modify the insulin secretory response. One possible explanation for these findings is that at D17G the microtubules are not coupled physicochemically to other molecules or structures necessary for their role in insulin secretion to be expressed fully.

Plasma exchange in Goodpasture's syndrome

The clinical course and levels of anti-glomerular basement membrane (GBM) antibody were compared in 20 patients with Goodpasture's syndrome treated with plasma exchange and immunosuppression (8 patients), immunosuppression alone (4 patients) or no specific therapy (8 patients). There was a more rapid fall in the level of anti-GBM antibody and pulmonary hemorrhage was less protracted in the 8 patients treated with plasma exchange and immunosuppression. In this group, 1 patient who presented with severe renal failure showed a marked improvement of renal function and there was no progression of disease in the 4 with milder renal involvement. 2 of the 4 patients treated with immunosuppression alone, and only 2 of the 8 patients who received no specific therapy, maintained normal renal function. In the group which received no specific therapy, 1 of the 6 patients who progressed to renal failure had mild renal involvement initially. There was a significant correlation between the level of anti-GBM antibody and the severity of the morphological changes seen at renal biopsy but not between the level of anti-GBM antibody and the severity of lung hemorrhage. The course and outcome of the disease in those patients not treated, or treated with immunosuppression alone, was better than that described in early reports of this disease, while those patients with plasma exchange and immunosuppression fared even better. An adequately stratified controlled trial of immunosuppression and plasma exchange versus immunosuppression alone is in order.

Serological complications of a major ABO incompatible bone marrow transplantation in a Polynesian with aplastic anemia

A 24-year-old, blood-group O Polynesian woman with multiple red blood cell antibodies received a group A, HLA-compatible, sex-matched bone marrow transplantation as treatment for severe aplastic anemia. High retransplantation titers of ABO isohemagglutinins were successfully reduced by repeated plasmaphereses. Despite gross in vitro incompatibility in the routine crossmatch, technetium-labelled red blood cell survival studies performed immediately prior to transplantation predicted that a small proportion of the donor erythrocytes would neutralize residual postplasmapheresis isoantibody. Donor marrow was subsequently infused without significant hemolysis. Although anti-A titers were low immediately posttransplantation, these rose progressively, approaching pretransplantation levels at the time of documented marrow engraftment at day 18. One week later the bone marrow graft was rejected. Retransplantation was successfully performed using marrow from an ABO compatible, sex-mismatched sibling donor. Radioisotopic studies were helpful in evaluating donor-recipient red blood cell incompatibility during the ABO incompatible transplantation, and again at retransplantation in the presence of circulating isoantibody to donor red blood cells. High levels of ABO isoagglutinins prior to plasmapheresis and rapidly rising titers posttransplantation may have predicted bone marrow graft rejection in this patient.

Preparation of leucocyte poor blood for transfusion

Three methods for the preparation of leucocyte poor red cells for transfusion have been evaluated. A new filtration (IMUGARD) method produced an easily prepared high quality leucocyte-poor preparation but which was not suitable for prolonged storage. A simple centrifugation method was suitable for the preparation of a sterile long life leucocyte-poor preparation and could be used for the majority of patients. A dextran sedimentation method was efficient in leucocyte removal but with the loss of a significant proportion of red cells.

Changes of blood oxygen affinity in different CPD solutions during liquid storage

Soft and hard-packed red blood cells in four different CPD anticoagulant-preservative solutions were stored with and without added glucose, adenine, and electrolytes. The hemoglobin-oxygen affinity of the red blood cell concentrates was tested over a six-week storage period. No single solution conferred better protection than any other against an expected increase in oxygen affinity due to loss of 2,3-DPG during storage. In all solutions, P50 at pH 7.4 decreased linearly when measured in a physiological system using CO2. After six weeks' storage at 4 C, the normal oxygen-binding properties of red blood cells could be restored in all instances following incubation for one hour in a rejuvenation solution. By contrast, red blood cell ATP levels were highest when resuspending solutions contained adenine and added glucose, but did not significantly compensate the allosteric role of 2,3-DPG in regulating oxygen affinity when the latter became depleted.

Improved survival from acute lymphoblastic leukemia in adolescents and adults

Nineteen adult patients with acute lymphoblastic leukemia were treated with combination chemotherapy to induce remission in the period from 1971 to 1979. Those patients achieving remission received intensive post-remission therapy with central nervous system (CNS) prophylaxis, followed by two-drug maintenance therapy, and reinduction courses of chemotherapy every six months. Remissions were achieved in 17 of the 19 patients (89%). Twelve patients (63%) are alive, 11 currently in complete remission. Two patients who experienced relapses in recent months have successfully undergone transplantation with allogeneic marrow from sex-matched, HLA-compatible sibling donors. The median survival and median duration rates of first remissions have not yet been reached, but to date are 36+ months and 29+ months, respectively with a predicted five-year survival rate of 61%. These results not only are significantly better than those achieved in the years 1968 to 1971 in our institution, but also are superior to others reported in the world medical literature. The combination of optimal treatment protocols with allogeneic marrow transplantation for patients with poor prognoses is expected to improve the survival of adult patients even further in the next decade.

Comparison of 7 and 12 day bone marrow CFUc culture in adult acute non lymphoblastic leukaemia

Bone marrows from 17 patients with acute nonlymphoblastic leukaemia (ANLL) were serially cultured on semisolid agar during periods of intensive remission induction chemotherapy and during remission. Of 12 patients achieving remission, six showed recovery of 7 and 12 day colony forming units (CFUc) culture to normal. However, in four of the six patients, recovery was short-lived with reappearance of typically leukaemic culture patterns while still in remission by bone marrow and peripheral blood criteria. In individual patients, serial 7 day cultures frequently showed persisting or recurring leukaemia-associated patterns while 12 day cultures were normal. This study confirms the heterogeneity observed in the cultural characteristics of the CFUc in acute non lymphoblastic leukaemia. Bone marrow cultures in patients with ANLL following intensive remission induction chemotherapy appear to provide a more reliable indication of persisting leukaemia or early relapse if they are interpreted earlier at 7 days.

Therapeutic plasmapheresis by continuous flow cnetrifugation

This report reviews the experience at Auckland Hospital with continuous flow centrifugation as a mean of carrying out therapeutic plasmapheresis. Over a three year period from August 1975, 26 patients, most with dysproteinaemias or Goodpasture's syndrome, were treated with a total of 260 therapeutic procedures.