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At least 973 records · Page 54Linked to original sources
PubMed2005

Regional distribution and extent of perfusion abnormalities, and the lung to heart uptake ratios during exercise thallium-201 SPECT imaging in patients with cardiac syndrome X.

BACKGROUND: Cardiac syndrome X is defined as angina-like chest pain with transient ischemic ST-segment changes during exercise and angiographically normal epicardial coronary arteries. Studies with myocardial perfusion imaging in this syndrome have indicated that some patients, but not all, have an abnormality on perfusion scan. However, the impact of these perfusion abnormalities on pulmonary thallium uptake is not clear in this group of patients. OBJECTIVE: To evaluate the regional distribution and extent of perfusion abnormalities, and the lung to heart (L:H) uptake ratios using exercise thallium-201 single-photon emission computed tomography (TI-201 SPECT) in patients with cardiac syndrome X. METHODS: The study group consisted of 31 selected cardiac syndrome X patients with regional perfusion abnormalities during exercise TI-201 SPECT imaging. A control group included 26 healthy subjects with normal coronary angiograms, exercise testing and exercise TI-201 SPECT imaging. Exercise TI-201 SPECT results were analyzed with further estimation of the L:H ratios, number and localization of regional perfusion defects, and their mean extent scores expressed in pixels and in per cent of the left ventricular wall. Twenty-two patients with known coronary artery disease were also included in the analysis of the L:H ratios. RESULTS: Multiple perfusion defects were detected in 13 (42%) patients and perfusion defects of single localization were detected 18 (58%) patients. All patients had reversible perfusion abnormalities: 21 (67.7%) had anterior, 14 (45.2%) had inferior and 12 (38.7%) had lateral localization of perfusion defects. The analysis of the extent of the perfusion defects revealed that the mean scores of the extent of the single regional defects were 38.61+/-43.8 pixels and those of multiregional defects were 106.1+/-55.2 pixels, which corresponded to 6.05+/-1.8% and 16.6+/-5.4% of the left ventricular wall defects, respectively. Patients with cardiac syndrome X had a significantly higher L:H ratio during exercise than the healthy subjects (0.46+/-0.02 versus 0.34+/-0.03, P<0.01). In addition, L:H ratios were found to be higher in patients with multiple perfusion defects (0.50+/-0.02) than in patients who had only anterior (0.45+/-0.08) or inferior (0.43+/-0.02) perfusion defects (P<0.05 for both). There were no statistically significant differences in the rest L:H ratios between the study and control groups. Also, no significant differences were observed in exercise L:H ratios between the cardiac syndrome X patients and the patients with coronary artery disease (0.46+/-0.02 versus 0.49+/-0.03, P>0.05). CONCLUSIONS: The results suggest that multiple perfusion defects in multiple vascular regions are relatively common in cardiac syndrome X patients, with the majority of these patients having at least one abnormal perfusion bed. Patients with this syndrome who have perfusion abnormalities also had significantly higher L:H ratios during exercise than did the control patients. Increased exercise L:H ratios were more prominent in patients with multiple perfusion defects.

Adult↗
PubMed1998

Sequential transfer of free flap to two defects.

This case report describes the use of a single lateral arm flap sequentially transferred to two defects in a bilateral hand injury. We believe this is a novel approach in reconstructing defects in bilateral hands when a staged reconstruction is planned.

Adult↗
PubMed1986

Visual field defects for vergence eye movements and for stereomotion perception.

An objective visual field can be mapped in terms of stimulus-induced eye movement. The authors used the scleral coil technique to record vergence and conjugate eye movements while stimulating different visual field locations with a 3 X 3 deg target whose image vergence was oscillated. For each of three subjects tested there was a visual field location where vergence eye movements were much weaker than in a control location of equal retinal eccentricity. On the other hand, conjugate eye movements driven from these two locations by lateral motion were similar. Field defects for ocular vergence coincided with regions in which oscillating retinal disparity failed to produce a sensation of motion in depth, although visual responses to static disparity were normal, and psychophysical thresholds for lateral motion showed no defect with either binocular or monocular viewing. It was concluded, therefore, that the perceptual stereomotion scotomata were not due to a monocular loss, but to a defective binocular interaction between motion signals from the left and right eyes, and that this defective interaction was specific for opposed rather than parallel motion in the two eyes. Furthermore, the visual loss was specific for motion rather than for position. The correlation between the field defects for ocular vergence and stereomotion perception leads the authors to suggest that the same defect in binocular interaction is responsible for both the eye movement and sensory abnormalities. Two candidate hypotheses are proposed: one is framed in terms of a single population, and the other in terms of two populations of cortical neurons.

Blindness↗
PubMed2006

Subjective visual tilt and lateral instability after vestibular deafferentation.

CONCLUSION: Defective utricular function, reflected by deviation of the perceived visual horizontal or vertical, cannot by itself explain increased postural sway in the lateral direction for patients with unilateral vestibular deafferentation (uVD). OBJECTIVE: It is not known why some patients with chronic uVD report distressing unsteadiness while others do not. The objective of this study was to test the hypothesis that impaired utricular compensation, reflected by pathologic tilt in the subjective visual horizontal and vertical (SVH-V) test, would affect postural control in the lateral direction after uVD. PATIENTS AND METHODS: The SVH-V was tested in 28 patients 6 months after translabyrinthine surgery for unilateral vestibular schwannoma, and correlated with posturography results. RESULTS: No increase in lateral and anterior-posterior sway, or the quotients between them, or for Romberg quotients, was found with increasing SVH-V tilt.

Adult↗
PubMed1989

Surgical implications of atrial septal defect complicating aortic balloon valvuloplasty.

An 80-year-old man underwent percutaneous transluminal balloon valvuloplasty for critical aortic stenosis. The procedure was performed by the antegrade atrial transseptal approach and was complicated by a persistent atrial septal defect. Symptoms recurred 6 months later, restenosis of the aortic valve was confirmed, and the atrial septal defect yielded a substantially greater left-to-right shunt. This complication of percutaneous transluminal balloon valvuloplasty poses important problems in hemodynamic assessment and operative management of patients who undergo subsequent aortic valve replacement.

Aged↗
PubMed2003

Cesarean scar dehiscence and irregular uterine bleeding.

BACKGROUND: Abnormal uterine bleeding is a frequent symptom in gynecology, caused by functional as well as by anatomic genital tract abnormalities. CASE: An endocervical diverticulum was diagnosed in a patient with secondary infertility, intermenstrual bleeding, and a prior cesarean delivery. Dehiscence of the cesarean scar was visualized by ultrasound, hysterosalpingogram, and hysteroscopy. The defect was repaired and the bleeding stopped. A spontaneous pregnancy occurred but ended in premature delivery at 17 weeks' gestation. Recurrence of chronic bleeding led to a hysterectomy 6 months later. CONCLUSION: Uterine scar defects may be associated with intermenstrual bleeding in women with a previous cesarean delivery.

Adult↗
PubMed2001

Two-stage reconstruction of bilateral alveolar cleft using Y-shaped anterior-based tongue flap and iliac bone graft.

OBJECTIVE: When an alveolar cleft is too large to close with adjacent mucobuccal flaps or large secondary fistula following a primary bilateral palatoplasty exists, a one-stage procedure for bone grafting becomes challenging. In such a case, we have used the tongue flap to repair the fistula and cleft alveolus followed by bone grafting to the cleft defect performed several months later. The purpose of this article is to report on our experiences with the use of an anteriorly based Y-shaped tongue flap to fit the palatal and labial alveolar defects and on the ultimate result of the bone graft. PATIENTS: A series of 14 patients were treated with this approach from January 1994 to December 1998. The average age of the patients was 15.8 years (range 5 to 28 years). The mean period of follow-up following the second stage bone graft operation was 45.9 months (range 9 to 68 months). In 9 of the 14 patients, the long-fork type of a Y-shaped tongue flap was used for extended coverage of the labial-side alveolar defects with the palatal fistula; in the remaining patients, the short-forked design was used. RESULTS: All patients demonstrated a good clinical result after the initial repair of cleft alveolus and palatal fistula. There was no fistula recurrence, although partial necrosis of distal margin in long-forked tongue flap occurred in one patient. Furthermore, the bone graft, which was performed an average of 8 months after the tongue flap repair, was always successful. Occasionally, transferred tongue tissue bulging interfered with the hygienic care of nearby teeth; however, these problems could be solved with proper contour-plasty performed afterward. No donor site complications such as sensory disturbance, change in taste, limitations in tongue movement, normal speech impairments, or tongue disfigurement were encountered. CONCLUSION: This two-stage reconstruction of a bilateral cleft alveolus using a Y-shaped tongue flap and iliac bone graft was very successful. It may be indicated for a bilateral cleft alveolus patient in which the direct closure of the cleft defect with adjacent tissue or the buccal flap is not easy because of scarred fibrotic mucosa and accompanied residual palatal fistula.

Adolescent↗
PubMed1987

Effects of periosteal activation agent on bone repair and ingrowth.

A substance that activates the resting periosteum (PAA) was applied to the periosteal surface in two different healing models using the femurs of 2-kg male rabbits. The activation agent was applied to the periosteal surface over the sites of circular defects drilled through the lateral cortex in one model and over the sites of porous polyethylene implants placed in the lateral cortex and the medullary canal in the other model. Results failed to show that the agent either enhanced bone ingrowth into the porous implants or accelerated bony filling of the circular defects. However, there was indication of enhanced mineralization and periosteal callus formation as early as 24 h after application.

Animals↗
PubMed1991

Treatment of nonunion by percutaneous injection of bone marrow and demineralized bone matrix. An experimental study in dogs.

Successful treatment of nonunited fractures remains a major clinical challenge. Because bone marrow and demineralized bone matrix (DBM) are capable of stimulating osteogenesis, experiments were designed to test the effectiveness of bone marrow or DBM or both when injected percutaneously into a canine nonunion model. Six-millimeter segmental defects were created in the midtibial diaphysis of 24 adult mongrel dogs and held distracted by external fixation. For comparative purposes, a 0.5-mm osteotomy was created in five dogs. Five weeks later, the 6-mm defects were injected with either saline, autogeneic marrow, DBM powder, a composite of bone marrow and DBM, or treated by open grafting techniques with autogenic cancellous bone. Healing of the defect was evaluated roentgenographically, biomechanically (three-point bending), histologically, and biochemically 13 weeks postsurgery. Marrow and DBM stimulated defect healing. However, the combination of bone marrow with DBM produced a synergistic response in the defect, which was greater than the sum of either marrow or DBM alone. Healing in the composite-grafted dogs was comparable to those treated by standard cancellous bone grafting. These data suggest that percutaneous injection of bone marrow and DBM may be a potential alternative that offers numerous advantages over standard open grafting techniques in the treatment of fractures with nonunited defects.

Animals↗
PubMed2004

Tissue-engineered injectable bone regeneration for osseointegrated dental implants.

The present study investigated a correlation between osseointegration in dental implants and an injectable tissue-engineered bone, using mesenchymal stem cells (MSCs) and platelet-rich plasma (PRP). Initially, the teeth in the mandible region were extracted and the healing period was 1 month. Bone defects on both sides of the mandible were prepared with a trephine bar. The defects were implanted with graft materials as follows: PRP, dog MSCs (dMSCs), and PRP, autogenous particulate cancellous bone and marrow (PCBM), and control (defect only). Two months later, the animals were evaluated by histology, and at the same time dental implants were installed. Two months later, the animals were sacrificed and nondecalcified sections were evaluated histologically and histometrically. According to the histological observations, the dMSCs/PRP group had well-formed mature bone and neovascularization, compared with the control (defect only) and PRP groups, as was the same for the PCBM group. A higher marginal bone level was observed around implants with PRP, PCBM, and dMSCs/PRP compared with the control. Furthermore, the values describing the amount of bone-implant contact (BIC) at the bone/implant interface were significantly different between the PRP, PCBM, dMSCs/PRP, and control groups. Significant differences were also found between the dMSCs/PRP and control groups in bone density. The findings of this experimental study indicate that the use of a mixture of dMSCs/PRP results in good results such as the amount of BIC and bone density comparable with that achieved by PCBM.

Animals↗
PubMed1992

Generation and analysis of defective genomes of Autographa californica nuclear polyhedrosis virus.

We have generated defective genomes of Autographa californica nuclear polyhedrosis virus (AcNPV) by serial, undiluted passage in IPLB-SF-21 cell culture in an attempt to identify potential cis-acting sequences important for AcNPV DNA replication. Viral DNA isolated from some of the 81 serial passages was analyzed by pulsed-field gel electrophoresis, restriction endonuclease analysis, and Southern blot hybridization. AcNPV-defective genomes appeared to be generated through a series of successively smaller and transiently stable intermediates. Although the defective genomes at passages later than passage 65 (P65) were somewhat heterogeneous in size, those of the majority of the population had a mean size estimated to be 50 kb, or 40% of that of standard virus. Defective genomic DNA at P81 hybridized strongly only to a 2.8-kb region mapping within 85.0 to 87.2 map units of AcNPV DNA (most of HindIII-K and a small part of HindIII-B), suggesting that the majority of P81-defective genomes were missing most of the 128-kb wild-type DNA sequence, except for this small 2.8-kb fragment. Furthermore, our results indicated that the defective genomes of P81 were composed largely of reiterations of this sequence. We suggest that the 2.8-kb DNA segment retained by the defective AcNPV genomes of P81 contains an important cis-acting element(s) sufficient for viral DNA replication in AcNPV-infected cells.

Animals↗
PubMed1987

[Chronic glaucoma treated by trabeculoretraction. Medium-term study of perimetric changes].

Authors use the Octopus 2000 automatic perimeter to study the evolution of visual field defects of 37 glaucomatous eyes treated by argon laser trabeculoplasty and followed up for one year. In a first time, half inferior laser trabeculoplasty is performed; half superior complement is done three months later if visual field defects improve. Various visual fields are compared by statistic delta program. Three months after trabeculoplasty more than 85% of visual field loss decrease or are stabilized. The same results are found after one year, without modification of initial medication.

Adult↗
PubMed1992

Orbito-palpebral reconstruction in anophthalmos and severe congenital microphthalmos.

In patients with congenital anophthalmos and severe microphthalmos, a tiny orbit and socket exist with little eyelids, frequently preventing retention of a standard conformer or prosthesis. Socket expansion is sometimes impossible with microorbitism; the retention of a prosthesis is also difficult when malformations of the eyelids exist. The treatment of these difficult cases includes three stages. The first stage is orbital expansion that depends on the cephalometric studies of the patient: transverse osteotomy on the maxilla and the zygomatic bone with lateral bar by extracranial route, vertical osteotomy on the roof of the orbit by intracranial route. In some cases, the osteotomy includes expansion in the transverse and vertical diameter with bone grafts in the defects and on the lateral and superior rims. Simultaneously, socket expansion is performed by incision of the conjunctival sac circumferentially, with mucosal or split skin grafts on a conformer. The second stage includes eyelid reconstruction by different flaps. A third stage is frequently needed for correction of eyelid malposition on the prosthesis: ptosis, entropion surgery. Two cases of congenital anophthalmos are reported. Methods and indications of treatment are discussed.

Adolescent↗
PubMed1996

Cardiac function, metabolism and perfusion in Duchenne and Becker muscular dystrophy.

We studied 23 DMD and eight BMD patients using cardiac echo, 24 h ECG and positron emission tomography (PET) with the radiotracers N-13 ammonia and F-18 fluorine deoxyglucose. The ECG was abnormal in 23 cases with alterations in the PR and/or QT intervals, abnormal Q waves in the lateral leads and ST segment depression. Twenty-four hour ECG showed that patients were more likely to produce premature ventricular ectopic beats with advancing age and 17 patients had paroxysmal ST segment depression. LV function was normal or mildly reduced in 24 cardiac echoes. PET studies were visibly abnormal in 15 patients. Regional perfusion defects involving the apex, lateral or anterior left ventricular walls were present, nine cases demonstrated a corresponding increase in glucose metabolism. Three out of 15 demonstrated matched perfusion/metabolism defects. One BMD had severe LV dilation with globally poor perfusion and metabolism. The abnormalities seen with PET were confirmed with both quantitative and semi-quantitative analysis of radioactive counts. Similar results were obtained for both DMD and BMD, where both groups demonstrated significant regional perfusion/metabolism mismatches. We have shown a reduced uptake of N-13 ammonia which is indicative of a reduction in myocardial perfusion. The use of N-13 ammonia to measure perfusion has been validated in animal studies. PET with either N-13 ammonia- or oxygen labelled water can be used to measure myocardial perfusion. We chose N-13 ammonia as this was most readily available to us.

Adolescent↗
PubMed1995

Primary midline developmental field. I. Clinical and epidemiological characteristics.

Opitz [BD:OAS XXIX(1):3-37, 1993] has postulated that during early blastogenesis the entire embryo represents a single morphogenetic unit, the primary field. During this period, beginning gastrulation, the most important events are the formation of the midline and the mesoderm. Consequently, one could expect that dysmorphogenetic reactions of the primary field are likely to disturb more than one of the essential events of blastogenesis, such as fusion, lateralization, decussation, segmentation, morphogenetic movements, asymmetry formation, etc. I have used the 20,891 liveborn malformed infants identified by the Spanish Collaborative Study of Congenital Malformations (ECEMC) to analyze the concept of the primary field defect (DFD). The malformed children were separated into 4,679 children with only midline defects, 1,592 children with midline plus other non-midline anomalies, and 14,620 babies without midline defects. Sex, twinning, neonatal death, parental consanguinity, and other malformed first degree relatives in the family were analyzed in each group. Different defects were selected as indicators of specific morphogenetic events of blastogenesis. Cardiac and neural tube defect were selected as indicators of fusion anomalies; agenesis/hypoplasia of the corpus callosum were included as example of decussation defect; cyclopia as representation of the alteration of lateralization; vertebral defects as indicators of anomalies of segmentation; intestinal malrotation and omphalocele as representatives of the alteration of the morphogenetic movement; and, finally, infants with asplenia, polysplenia, dextrocardias, transposition of great vessels, visceral transposition, and situs inversus totalis were grouped to allow an analysis of alteration of the normal body asymmetry.(ABSTRACT TRUNCATED AT 250 WORDS)

Congenital Abnormalities↗
PubMed2001

Modified bilateral neurovascular cheek flaps: a new technique for reconstruction of extensive upper lip defects.

The authors present a modified bilateral neurovascular cheek flap as a new technique for extensive upper lip reconstruction. The technique is modified from the bilateral neurovascular cheek flap for lower lip reconstruction described by Vatanasapt and colleagues in 1987 by designing rectangular and triangular flaps in the cheek tissues lateral to the lip defect on both the skin and the mucosal sides. This method has the advantage of preserving neurovascular structures as well as the original position of the oral commissure. Five patients are presented with acceptable surgical results. The technique is a good choice for functional reconstruction of near-total or total upper lip defects.

Aged↗
PubMed1998

The distally based lateral adipofascial flap.

The distally based lateral adipofascial flap can be based either on the lowermost perforator or the anterior perforating branch of the peroneal artery avoiding sacrifice of the main peroneal artery. It has been used successfully to resurface soft tissue defects either on the lateral or medial aspect of the lower third of the leg in 13 cases. The size of these flaps varied from 2.0 cm x 5.0 cm to 4.5 cm x 15.0 cm in size. These cases had minimal donor site morbidity and had positive aesthetic results. The advantages were: 1. Choice of either the lowermost perforator or the anterior perforating branch giving a wide arc of rotation; 2. Preservation of the superficial peroneal nerve; 3. Primary closure of the donor site.

Adult↗
PubMed2001

[Is cancer a hereditary or a degenerative disease?].

All malignancies, whether they are solid tumors or leukemias, always originate from modifications of the genetic information of the cells. In most cases these changes occur in a single cell, which will then generate a whole series of malignant cells through cell division. In these cases the cancer is sporadic and therefore not hereditary. In a small percentage of the cases the DNA defects are inherited from one of the parents. All cells of the body will then carry this defect, but only a few tissues will become cancerous later in life based on this defect. These forms of cancer, such as some forms of breastca, colonca, thyroidca a.o. are hereditary. Nevertheless the malignant process will not be initiated in all individuals who carry these defects and the age at onset cannot be predicted with precision. In some malignancies, whether sporadic or hereditary, the first gene that carries a defect will be essential for normal cellular function. As a result, the malignant behavior of the cells becomes irreversible. Gradually, additional defects will accumulate in other genes in these cells leading to an increasing malignant behavior of the cancer. In other cases the consequences of the first defect remain limited but the accumulation of additional defects in other genes is facilitated resulting in an increased aggressive behavior of the cells. The environmental factors that cause or facilitate the occurrence of the first DNA defect in the cells, or that facilitate the initiation of hereditary cancers remain largely unknown. Chance plays of course an important role since we accumulate continuously defects in our DNA. Nevertheless evidence exists for the presence of components in our atmosphere, our food or beverages that facilitate the accumulation of defects in our DNA. The identification of these components provides an important starting point for improved prevention. In the mean time, making genetic tests available to individuals at risk for hereditary cancers remains an important, be it delicate task, since they can potentially influence their chances of survival. The improving insights into the mechanisms involved in the pathogenesis of cancers guarantees a better and more efficient treatment in the future.

Age of Onset↗