Enhanced ability of the progenipoietin-1 to suppress apoptosis in human hematopoietic cells

Repopulating hematopoietic cell compartments after myeloablative chemotherapy remains a key factor in a successful chemotherapy program. Modified and chimeric cytokines have been developed to help reduce inflammation, fever and hospitalization time for patients. A chimeric cytokine, progenipoietin-1 (ProGP-1), containing the G-CSF and FL receptor agonists binds both the G-CSF receptor and FLT-3. It also stimulates the growth of dendritic cells, which play an important role in immunotherapy. While in vivo effects of ProGP-1 are well described, the mechanisms by which it stimulates growth are not well understood. We have investigated the effects of ProGP-1 on prevention of apoptosis in the human hematopoietic cell line OCI-AML.5. ProGP-1 promoted cellular proliferation better than G-CSF or FL separately but stimulated proliferation similar to their co-addition as demonstrated by growth curves and [3H]-thymidine incorporation. ProGP-1 prevented apoptosis to a greater degree than G-CSF or FL alone as determined by annexin V/propidium iodide binding and TUNEL assays. ProGP-1 promoted maintenance of the mitochondrial membrane potential better than G-CSF or FL alone. In addition, Pro-GP promoted a lower redox potential as higher levels of free radicals were detected after cytokine treatment than in cytokine-deprived cells implying increased respiration. These data indicate that ProGP-1 promotes the proliferation and prevents the apoptosis of human hematopoietic cells better than FL or G-CSF alone, and to a similar extent as their co-addition. Thus, ProGP-1 can be used to repopulate certain hematopoietic cells as a single entity rather than the introduction of two different cytokines.     

Slitlamp stretching of the corneal flap after laser in situ keratomileusis to reduce corneal striae

PURPOSE: To examine the efficacy of treating immediate postoperative corneal striae and poor flap alignment by stretching the corneal flap at the slitlamp with a cotton-tip applicator and compare the results using this technique with those using the conventional technique of refloating the flap with balanced salt solution (BSS(R)). SETTING: TLC Laser Eye Center, Garden City, New York, USA. METHODS: Charts of 7154 eyes having laser in situ keratomileusis (LASIK) were reviewed retrospectively. During the 11 months prior to January 1, 2000, 3516 eyes had LASIK. Patients with flap striae or a malpositioned flap at the immediate slitlamp evaluation were treated by refloating the flap (Group A). During the 11 months subsequent to January 1, 2000, 3638 eyes had LASIK. Patients with flap striae or a malpositioned flap at the immediate slitlamp evaluation were treated by flap stretching with a cotton-tip applicator (Group B). The number of eyes that required retreatment for flap striae was analyzed. RESULTS: Twenty-nine eyes in Group A (0.82%) required retreatment for visually significant flap striae after day 1, and 11 eyes in Group B (0.30%) required retreatment. A loss of best corrected visual acuity occurred in 3 Group A eyes and 2 Group B eyes. CONCLUSIONS: During the immediate postoperative period, stretching the flap with a cotton-tip applicator was a simple, safe, and effective technique for reducing visually significant flap striae. Unlike refloating the flap with BSS, flap stretching at the slitlamp does not require additional anesthesia, exposure time, or dehydration of the ocular surface.     

A successful strategy for preimplantation genetic diagnosis of myotonic dystrophy using multiplex fluorescent PCR

The most common form of inherited muscular dystrophy in adults is myotonic dystrophy (DM), an autosomal-dominant disease caused by the expansion of an unstable CTG repeat sequence in the 3' untranslated region of the myotonin protein kinase (DMPK) gene. Expanded (mutant) CTG repeat sequences are refractory to conventional PCR, but alleles with a number of repeats within the normal range can be readily amplified and detected. Preimplantation genetic diagnosis (PGD) of DM has been successfully applied. However, a misdiagnosis using the reported protocol was recently documented. Two new PGD protocols for DM have been developed which utilise multiplex fluorescent PCR. Ideally a linked polymorphic marker, APOC2, is amplified in addition to the normal DMPK alleles, thus providing a back-up diagnostic result. However, the two couples reported in the present study were not fully informative at the APOC2 locus and so an unlinked short tandem repeat (STR) marker, D21S1414, was substituted. The highly polymorphic nature of the D21S1414, DMPK and APOC2 loci means that a very simple genetic fingerprint can be generated by analyses of these loci. This allows most DNA contaminants to be detected. Contamination is a significant problem for PGD and is the primary reason for the inclusion of D21S1414 and APOC2 in this protocol. This paper reports the first clinical experience and pregnancies following PGD for DM using a multiplex fluorescent PCR protocol.     

Initial experience with an active-fixation defibrillation electrode and the presence of nonphysiological sensing

Nonphysiological sensing by a pacing and defibrillation electrode may result in inappropriate defibrillator discharges and/or inhibition of pacing. Active-fixation electrodes may be more likely to sense diaphragmatic myopotentials because of the protrusion of the screw for fixation. In addition, the movement of the fixation screw in an integrated bipolar lead system could also result in inappropriate sensing. This may be increasingly important in patients who are pacemaker dependent because the dynamic range of the autogain feature of these devices is much more narrow. Five of 15 consecutive patients who received a CPI model 0154 or 0155 active-fixation defibrillation electrode with an ICD system (CPI Ventak A V3DR model 1831 or CPI Ventak VR model 1774 defibrillator) are described. In 2 of the 15 patients, nonphysiological sensing appearing to be diaphragmatic myopotentials resulted in inappropriate defibrillator discharges. Both patients were pacemaker dependent. Changes in the sensitivity from nominal to less sensitive prevented inappropriate discharges. In one patient, discreet nonphysiological sensed events with the electrogram suggestive of ventricular activation was noted at the time of implantation. This was completely eliminated by redeployment of the active-fixation lead in the interventricular septum. In two other patients, discreet nonphysiological sensed events resulted in intermittent inhibition of ventricular pacing after implantation. These were still seen in the least sensitive autogain mode for ventricular amplitude. These were not seen on subsequent interrogation 1 month after implantation. Increased awareness of nonphysiological sensing is recommended. The CPI 0154 and 0155 leads seem to be particularly prone to this abnormality. Particular attention should be made when deploying an active-fixation screw for an integrated bipolar lead. This increased awareness is more important when a given individual is pacemaker dependent, which may warrant DFT testing in a least or less sensitive mode in these patients.     

Multiple clinical manifestation of HTLV1 infection in a single patient

HTLV-1 infection is endemic in the Caribbean and several publications have reported the clinical disease entities seen in this population of patients. This case report is an account of a patient admitted to Kingstown General Hospital, St Vincent and the Grenadines, who had severe infective dermatitis, tropical spastic paraparesis (TSP) and Non-Hodgkin's Lymphoma (NHL). As far as we are aware, all three diseases have not been described in a single patient.     

Spontaneous resolution of diffuse alveolar septal amyloidosis

Amyloidosis is a generic term for a heterogeneous group of disorders associated with deposition of protein in an abnormal fibrillar form. Amyloidosis can be hereditary or acquired, localised or systemic and potentially lethal or merely an incidental finding. We report a case of a male who was totally asymptomatic and was incidentally detected to have lung amyloidosis. He was not given any treatment but kept under observation., His chest radiograph (CXR) and high resolution computed tomograph (HRCT) of the chest cleared spontaneously after one year and the patient continues to remain asymptomatic even after two years.     

A case of Miller-Dieker syndrome in a family with neurofibromatosis type I

The Miller-Dieker syndrome (type I lissencephaly) is a neuronal migration disorder which is associated with microdeletions in the short arm of chromosome 17. Neurofibromatosis type I (NF1) is an autosomal dominant condition associated with mutations in the long arm of chromosome 17, and characterised by neurofibromas, café-au-lait spots and axillary freckling. The neonatal period for a female infant born at 39 weeks gestation by emergency Caesarean section was complicated by frequent epileptic seizures as well as hypotonia. A computed tomography scan revealed evidence of lissencephaly, and chromosomal analysis showed a microdeletion on the short arm of chromosome 17 (17p13.3), confirming the diagnosis as Miller-Dieker syndrome. The child died at the age of 4 years and examination of the brain confirmed lissencephaly with a thickened cortex, deficient white matter, and grey matter heteropias. The mother had café-au-lait spots, and axillary freckling. In addition, the mother’s and maternal grandmother’s genetic analysis showed identical mutations in the neurofibromatosis I gene on the long arm of chromosome 17, confirming the diagnosis of NF1. The child did not possess the mutation. This case illustrates a rare neuronal migration disorder appearing in a child from a family with a history of NF1. Received: 15 April 1999 / Revised, accepted: 30 July 1999