Band Insertion Research Articles

Commentary

In the article by Alva and associates, the authors report their institutional experience with double-chambered right ventricle over an 8-year period. This report serves to expand our knowledge on the morphologic nature of this entity. Their objective was to study the muscular division of the right ventricle by correlating morphologic, echocardiographic, and angiographic findings. Double-chambered right ventricle, the partitioning of the right ventricle into 2 chambers, has been recognized since at least 18671Peacock T. Malformation of the human heart.in: Churchill and Sons, London1967: 75-79Google Scholar and is produced by prominent anomalous muscle bundles within the right ventricular cavity. Although frequently associated with membranous ventricular septal defects,2Simpson W Sade R Crawford F Taylor A Fyfe D. Double-chambered right ventricle.Ann Thorac Surg. 1987; 44: 7-10Abstract Full Text PDF PubMed Scopus (26) Google Scholar other anatomic forms have also been reported.3Baumstark A Fellows K Rosenthal A. Combined double chambered right ventricle and discrete subaortic stenosis.Circulation. 1978; 57: 299-303Crossref PubMed Scopus (41) Google Scholar, 4Gallucci V Scalia D Thiene G Mazzuco A Valfre C. Double-chambered right ventricle: surgical experience and anatomical considerations.Thorac Cardiovasc Surg. 1980; 28: 13-17Crossref PubMed Scopus (17) Google Scholar, 5Rowland T Rosenthal A Castaneda A. Double chamber right ventricle: Experience with 17 cases.Am Heart J. 1985; 89: 455-462Abstract Full Text PDF Scopus (67) Google Scholar Most recently, my colleagues and I6Moran AM Hornberger LK Jonas RA Keane JF. Development of a double-chambered right ventricle after repair of tetralogy of Fallot.J Am Coll Cardiol. 1998; 31: 1127-1133Abstract Full Text Full Text PDF PubMed Scopus (31) Google Scholar reported our own institutional experience of the development of double-chambered right ventricle in postoperative patients with tetralogy of Fallot, with a minimal occurrence rate of 3.1%. An underlying anatomic substrate was recently suggested by Wong and colleagues.7Wong PC Sanders SP Jonas RA Colan SD Parness IA Geva T et al.Pulmonary valve–moderator band distance and association with development of double-chambered right ventricle.Am J Cardiol. 1991; 68: 1681-1686Abstract Full Text PDF PubMed Scopus (64) Google Scholar They described the presence of a displaced insertion of moderator band into the septal band. This pattern of insertion was recognized both in pathologic specimens and in clinical cases. The evaluation in human beings used 2-dimensional echocardiographic methods. This displacement of the moderator band was further quantified as the distance of the insertion point from the pulmonary valve indexed to the tricuspid valve. The report by Alva and colleagues furthers our understanding of this pathologic entity. They confirm the frequent association with membranous ventricular septal defects and even include a single patient after repair of tetralogy of Fallot. By evaluating several normal anatomic specimens, they highlight the variability in the presence of the moderator band (noting prominent septoparietal trabeculations without the presence of a discrete moderator band in 2). More important, they provide quantitative evidence of 2 distinct anatomic subtypes of double-chambered right ventricle, suggesting that these represent either displaced septoparietal trabeculations or moderator bands that undergo marked hypertrophy. Finally, they provide a quantitative method for assessing the position of such muscle bars relative to the long axis of the right ventricle using angiographic imaging. It is unfortunate that they were unable to attempt a similar analysis using echocardiography, since this is the initial imaging modality of choice in the current era. This inability is sure to reflect the retrospective nature of their study. Although this report increases our knowledge of this intriguing anatomic entity, several questions are left unanswered. The prospective application of previously described ratios (listed above) to identify at-risk patients is awaited. If successfully validated, this could lead to “prophylactic interventions” at the time of other cardiac operations. Clinically, the long-term follow-up of surgically treated patients warrants evaluation, because we6Moran AM Hornberger LK Jonas RA Keane JF. Development of a double-chambered right ventricle after repair of tetralogy of Fallot.J Am Coll Cardiol. 1998; 31: 1127-1133Abstract Full Text Full Text PDF PubMed Scopus (31) Google Scholar have previously reported recurrence of such obstructions. Finally, the stimulus to hypertrophy in such patients is as yet unknown and may, in part, reflect altered flow dynamics. Further work is required.

Effects of continuous infusion of PTH on experimental tooth movement in rats.

Development of new methods for accelerating orthodontic tooth movement has been strongly desired for shortening of the treatment period. The rate of orthodontic tooth movement is dependent on the rate of bone resorption occurring in the compressed periodontium in the direction of orthodontic force applied to the tooth. In the present study, we examined the effects of continuous infusion of parathyroid hormone (PTH) on tooth movement. Male rats weighing 350-400 g were treated with subcutaneous of vehicle or hPTH(1-84) at 1-10 micrograms/100 g of body weight/day. When the upper right first molar (M1) was moved mesially for 72 h by the insertion of an elastic band between the first and second molars, M1 movement was accelerated by PTH infusion at 10 micrograms. PTH infusion caused a 2- to 3-fold increase in the number of osteoclasts in the compressed periodontium of M1, indicating that such treatment accelerated tooth movement by enhancing bone resorptive activity induced in the compressed periodontium. When M1 was moved mesially by an orthodontic coil spring ligated between upper incisors and M1 for 12 days, PTH(1-84) infusion at 10 micrograms caused a 2-fold increase in the rate of M1 movement. PTH(1-34) infusion at 4 micrograms had an effect comparable to that of PTH(1-84). However, intermittent injection of PTH(1-34) did not accelerate M1 movement. PTH infusion for 13 days did not affect either bone mineral measurements or the serum calcium level. These findings suggest that continuous administration of PTH is applicable to accelerate orthodontic tooth movement.

Effects of morphine on the distribution of Fos protein in the trigeminal subnucleus caudalis neurons during experimental tooth movement of the rat molar

The present study was undertaken to disclose temporal changes in the distribution of Fos-like immunoreactive (-IR) neurons in the trigeminal subnucleus caudalis (SpVc), one of the important relay nuclei for processing the nociceptive information from the oro-facial regions, following induction of experimental tooth movement in rat upper molars. Furthermore, the effect of morphine and naloxone on the levels of Fos-IR neurons in the SpVc was examined. The experimental tooth movement was induced by insertion of an elastic rubber between the first and second upper molars. In normal animals, Fos-IR neurons were rarely observed in the SpVc. Immediately after insertion of the elastic band, the distribution of Fos-IR neurons was comparable to that observed in normal animals. The number of Fos-IR neurons increased significantly from 1 to 4 h following the induction of experimental tooth movement, reaching a maximum at 2 h, and then decreasing gradually. Most of the neurons were localized in the dorsomedial portion of the superficial layers of the ipsilateral SpVc near the obex, but a few were observed at the ventral portion of the SpVc. The neurons at the superficial layers and ventral portion of the contralateral SpVc also showed Fos-like immunoreactivity, but their numbers were significantly smaller than those on the ipsilateral side. Pretreatment with morphine (3 and 10 mg/kg, i.p.) significantly reduced the induction of Fos-IR neurons at the superficial layers of the ipsilateral SpVc in a dose-dependent manner, and its effect was antagonized by the subsequent treatment of naloxone (2 mg/kg, i.p.). Naloxone pretreatment enhanced the expression of Fos-IR neurons on the ipsilateral SpVc. The present results of a reduction of Fos-IR neurons by morphine pretreatment suggest that the induction of Fos-IR neurons may be due to the noxious stimulation caused by induction of experimental tooth movement.

Red blood cell membrane disorders.

The recent discovery of the specific molecular defects in many patients with hereditary spherocytosis and hereditary elliptocytosis/pyropoikilocytosis partially clarifies the molecular pathology of these diseases. HE and HPP are caused by defects in the horizontal interactions that hold the membrane skeleton together, particularly the critical spectrin self-association reaction. Single gene defects cause red cells to elongate as they circulate, by a unknown mechanism, and are clinically harmless. The combination of two defective genes or one severe alpha spectrin defect and a thalassaemia-like defect in the opposite allele (alphaLELY) results in fragile cells that fragment into bizarre shapes in the circulation, with haemolysis and sometimes life-threatening anaemia. A few of the alpha spectrin defects are common, suggesting they provide an advantage against malaria or some other threat. HS, in contrast, is nearly always caused by family-specific private mutations. These involve the five proteins that link the membrane skeleton to the overlying lipid bilayer: alpha and beta spectrin, ankyrin, band 3 and protein 4.2. Somehow, perhaps through loss of the anchorage band 3 provides its lipid neighbours (Peters et al, 1996), microvesiculation of the membrane surface ensues, leading to spherocytosis, splenic sequestration and haemolysis. Future research will need to focus on how each type of defect causes its associated disease, how the spleen aggravates membrane skeleton defects (a process termed 'conditioning'), how defective red, cells are recognized and removed in the spleen, and why patients with similar or even identical defects can have different clinical severity. Emphasis also needs to be given to improving diagnostic tests, particularly for HS, and exploring new options for therapy, like partial splenectomy, which can ameliorate symptoms while better protecting patients from bacterial sepsis and red cell parasites, and perhaps from atherosclerosis (Robinette & Franmeni, 1977) and venous thrombosis (Stewart et al, 1996).

Cellular roles in relapse processes of experimentally-moved rat molars.

This histological study was designed to clarify the relapse processes of rat molars following orthodontic tooth movement by the Waldo method. An elastic band was inserted between the upper first and second molars, and removed either 7 or 21 days later. The relapse processes of first molars were examined at 1 or 4 days after completing the 7-day-insertion and at 5 or 10 days after the end of the 21-day-insertion. At the end of the 7-day-insertion period, the mean interdental space was 158 microns, but decreased rapidly, reaching 44 microns by 1 day after removal, and 16 microns by day 4. In the periodontal ligament (PDL) compressed by elastic band insertion, partial hyalinization and/or mineralization occurred. The stretched PDL consisted of irregularly-distributed, thin principal fibres, approximately 2.4 microns in diameter. On days 1 and 4 after removal, osteoclasts, macrophage-like cells and fibroblast-like cells were localized around hyalinized tissues, but thick principal fibres, approximately 3.8 microns in diameter, were regularly distributed throughout the PDL proper. The mean interdental space after the 21-day-insertion was 536 microns, but this had decreased to 108 microns by day 5, and 71 microns by day 10. On day 5 after removal, numerous osteoclasts were evenly distributed in the compressed PDL, while thick principal fibres, approximately 3.5 microns, were present in the stretched PDL. These results suggest that, during relapse of experimentally-moved rat molars, (i) rapid remodelling of the PDL and surrounding alveolar bones is the main cause of tooth relapse and (ii) hyalinized and/or mineralized tissues occurred by compression are rapidly resorbed by osteoclasts, macrophage-like cells and fibroblast-like cells.

Development of a Double-Chambered Right Ventricle After Repair of Tetralogy of Fallot

Objectives. We sought to determine the frequency, etiology and progressive nature of midcavity obstruction in patients after primary repair of tetralogy of Fallot (TOF).Background. Midcavity obstruction (double-chambered right ventricle [DCRV]) represents a significant portion of reoperations in patients who have had TOF repair. This group is still poorly defined.Methods. A retrospective review of clinical, echocardiographic and catheterization data for all patients with TOF who later underwent reoperation for DCRV was performed.Results. Between 1973 and 1995, 552 children <2 years of age underwent primary TOF repair (median age 6.7 months). Long-term follow-up (median 50 months) was available in 308 children. Of these, 17 children subsequently developed DCRV requiring reoperation. The median age at initial operation was 7.9 months. During a median follow-up interval of 43.2 months, murmur intensity increased in all patients, and the average subpulmonary gradient at catheterization increased from 24 ± 10 to 80 ± 27 mm Hg in seven children (p = 0.002) and at Doppler echocardiography from 14 ± 16 to 89 ± 18 mm Hg in five children (p = 0.002). Before reoperation, 6 of the 17 children were symptomatic. During the operation (median age 55.4 months), obstruction was relieved by incision of hypertrophied anomalous muscle bundles in all 17 patients, with prominent fibrosis noted in 8 patients. Excessive septal and parietal hypertrophy was noted in one child. No new transannular patches were required. Recurrent obstruction has reappeared in 3 of these 17 children during follow-up.Conclusions. DCRV is a medium-term complication of TOF repair in infants, with a minimal incidence of 3.1% (95% CI 1.8% to 4.9%). The condition is progressive and is due to anomalous muscle bundle hypertrophy or fibrosis, or both, which may represent displaced insertion of a moderator band. Further reobstruction does occur; continued careful follow-up is therefore essential.

In vitro measurement of three-dimensional tooth movement following insertion and removal of an elastic band between rat molars using a time-lapse video and radiography.

Three-dimensional tooth movements in vitro were examined for 20 hours following insertion of an elastic band between the rat mandibular first and second molars and then for 10 hours following removal of the band using a time-lapse video in combination with radiography. The first molar moved in a mesiolingual direction and the second molar, in a distobuccal direction following insertion of the band. The most pronounced expansion in the interdental space occurred during the first hour following the insertion of the band. Following the removal of the band, the expanded interdental space began to close immediately, however, the teeth had not returned to their initial positions by the end of the experimental period. Two distinct peaks were observed in the rates of tooth movement, one immediately following the insertion of the band and the other following its removal. Radiographic observations showed that the first molar exhibited a mesial tipping movement while the second molar exhibited not only a distal tipping movement but also an upward movement following the insertion of the band ; relapsing movements were also observed following the removal of the band. These results suggest that the present in vitro tooth movements were mainly caused by the biomechanical responses of the periodontal ligament to orthodontic forces, and that our method is relatively simple, compared to in vivo experiments, and may be a useful tool for further studies on three-dimensional tooth movements under various experimental conditions.

Identification of an internal topogenic signal sequence in human Band 3, the erythrocyte anion exchanger.

The insertion of Band 3, the human erythrocyte anion exchanger, into microsomal membranes was studied in an in vitro reticulocyte lysate translation system. Band 3 consists of a 43-kDa amino-terminal cytosolic domain and a carboxyl-terminal 52-kDa membrane domain containing up to 14 transmembrane segments with a single N-glycosylation site at Asn-642. Insertion of truncated Band 3 molecules into microsomal membranes was assayed by glycosylation, resistance to alkaline extraction, and tryptic removal of the cytosolic domain. Truncations containing either the first four or the last eight putative transmembrane segments were stably integrated into microsomes showing that an intact membrane domain was not required for membrane integration. Furthermore, the extracytosolic domain following the seventh transmembrane segment was properly translocated across the microsomal membrane and glycosylated whether the seventh transmembrane segment was the first, last, or the only transmembrane segment in the construct. The ability of the entire membrane domain, the truncated domain beginning with the seventh transmembrane segment, or the seventh transmembrane segment to insert into microsomes was dependent on the presence of the signal recognition particle receptor. The seventh transmembrane segment in Band 3 therefore has the topogenic properties of an internal signal sequence.

Using Maekawa's chart to calculate finite length barrier insertion loss

This paper describes a simple model for the calculation of finite length barrier insertion loss. The model is based on the concept of minimum diffracted paths. It makes use of Maekawa's empirical curve to estimate the attenuation associated with each diffracted path. However, instead of summing the energy contributions of the diffracted waves as suggested by Maekawa ( Applied Acoustics, 1 (1968) 157-73), a new formulation of the phase relationships between the waves is developed to allow pressure summation. The result is a model which is simple to use and yet has accuracy substantially better than Maekawa's energy summation method, in predicting both narrow and octave band insertion loss of finite length barriers. Extensive model experiments are used to verify the model. It is believed that the model is both simple and accurate enough to replace Maekawa's energy summation method in engineering practice.

Evaluation of methods of claw finger correction using the finger dynamography technique

Finger dynamography is a bedside technique for evaluation of the moving abilities and working space of the hand. Various operative procedures used for correcting the claw finger deformity restore the functional abilities to a varying extent. The palmaris longus transfer with insertion into Al–A2 pulley appears to be a better procedure than lateral band insertion, extensor diversion or extensor many-tail procedures. The use of palmaris longus as a motor seems to have advantages over flexor digitorum superficialis transfer where removal of FDS as a motor produces local deficits.

Ionizing radiation target groups of band 3 inserted into egg lecithin liposomes as determined by Raman spectroscopy.

The purified integral membrane protein, band 3, from human erythrocytes was inserted into egg lecithin liposomes. The insertion of band 3 was determined from thermal transition data from the analysis of the C--H stretching region bands recorded at temperatures from 25 to -22 degrees C. Raman spectra show that band 3 considerably broadens and lowers the thermal transition of egg lecithin liposomes, suggesting the insertion of band 3. The band 3-inserted liposomes were irradiated with gamma-rays (40 Gy) and the radiation target groups were determined by the analysis of the structural sensitive Raman bands in the 1600-1700 cm-1 (amide I), 1200-1300 cm-1 (amide III) and 550-1030 cm-1 (side chain amino groups) regions. The radiation-sensitive groups as identified from Raman spectra in the region 550-1030 cm-1 are tyrosines and cysteines. The radiation-induced changes in the secondary structure were determined from amide I and III bands. Quantitative estimation using the curve fitting method shows that band 3 contains 44% total helix, 48% beta strand and 8% undefined plus turns (error +/- 4%). The secondary structure changes to 35% total helix, 42% total beta-strand and 23% turned and undefined upon irradiating band 3 containing liposomes. We suggest that ionizing radiation preferably damages tyrosine and cysteine side chain residues and reduces the amount of alpha-helical configuration of band 3.

The effect of local application of 1,25-dihydroxycholecalciferol on osteoclast numbers in orthodontically treated rats.

Orthodontic tooth movement requires remodeling of periodontal tissues, especially alveolar bone. 1,25-(OH)2D3, the active form of vitamin D3, is known to be a potent stimulator of osteoclastic bone resorption. The purpose of this study was to investigate the effect of local application of 1,25-(OH)2D3 on osteoclast numbers induced by experimental tooth movement. A piece of orthodontic elastic band was inserted between the first and second upper molars of male Wistar rats weighing about 200 g each. Twenty microL of 1,25-(OH)2D3 (10(-12)-10(-7) mol/L) was injected locally into the submucosal palatal area of the root bifurcation of the right first molar. The left side was injected with phosphate-buffered saline (PBS). The number of osteoclasts was counted in a 700 x 1050 microns 2 area of the interradicular septum. The local injection of 1,25-(OH)2D3 caused a dose-dependent increase in osteoclast number. The effect of 1,25-(OH)2D3 reached a response plateau at 10(-10) mol/L when greater than a three-fold rise in osteoclast number was attained compared with the PBS-treated controls. While the insertion of a piece of elastic band for three days induced a significant increase in osteoclasts in the alveolar bone, daily injections of 20 microL of 10(-10) mol/M 1,25-(OH)2D3 for three days markedly stimulated the numbers of osteoclasts induced by the insertion of an elastic band. 1,25-(OH)2D3 was apparently synergistic with mechanical stimuli, resulting in enhancement of the numbers of osteoclasts induced by mechanical stimuli alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Pulmonary valve-moderator band distance and association with development of double-chambered right ventricle

Double-chambered right ventricle (DCRV), a form of right ventricular outflow obstruction that sometimes accompanies a ventricular septal defect (VSD), is associated with superior and rightward displacement of the septal insertion of the moderator band. It was hypothesized that this superior displacement is present and identifiable by echocardiography in patients with a VSD even before right ventricular outflow tract obstruction develops. Eight patients who had a previous echocardiographic study showing a VSD alone were echocardiographically diagnosed as having DCRV. Their initial echocardiographic studies were reviewed, and superior displacement of the moderator band was quantified by measuring the distance between the pulmonary valve and moderator band, normalized to tricuspid anulus diameter. These measurements were compared with those from the initial studies of the following 3 other groups: (1) an age-matched group of 10 patients with no structural heart disease; (2) an age-matched group of 10 patients with a VSD who did not develop DCRV; and (3) a group (not age-matched) of 10 patients with VSD and DCRV in whom subpulmonary obstruction was present on the initial study. The 8 patients who eventually developed subpulmonary obstruction had significant superior displacement of the moderator band at the time of their initial echocardiogram compared with that of the 2 age-matched control groups (p < 0.01). In contrast, there was no significant difference in moderator band displacement between these patients and the 10 with DCRV who already had right ventricular outflow obstruction at their initial study (p = not significant). Superior displacement of the moderator band is quantifiable by 2-dimensional echocardiography and may help to predict which infants with a VSD are at risk to develop subpulmonary obstruction.

Scintigraphic Manifestation of Iliotibial Band Injury in an Endurance Athlete

The scintigraphic appearance of an overuse injury at the insertion of the iliotibial band is described. This injury was depicted on three-phase bone scintigraphy as focally increased radionuclide concentration in the anterolateral tibial condyle (lateral tibial tubercle) where the iliotibial band inserts. Overuse injuries involving the insertion of the iliotibial band are uncommon and are not to be confused with a stress fracture or other bony lesion involving the lateral tibial condyle.

Geometric Approaches to Solve the Chebyshev Traveling Salesman Problem

Abstract: Several heuristic procedures based on geometric concepts have been developed for the Chebyshev (or too) Traveling Salesman Problem (CTSP),which has numerous applications in materials handling and information storage-retrieval. The following study is concerned with evaluating the performance of geometric approaches as a function of the shape of the service region and the number of points to be sequenced. A new approach, the band insertion heuristic, is also introduced and compared with existing procedures. Trade-offs in tour quality and solution effort are the primary focus of the study, which is empirical in nature; however, the results generally apply to a wide range of configurations.

Model of Intestinal Continence Using an Implantable Pulse Generator and a Myoprosthetic Sphincter

Past attempts at artificial continence using a wide range of surgical procedures and devices have met with only limited success because of excessive rates of infection, rejection, incomplete continence, and technical difficulty. Presented here is a model of artificial continence using a lumen-occluding Teflon loop powered by the rectus abdominus muscle and activated by an implantable pulse generator. Eight female mongrel dogs underwent laparotomy with creation of a Brooke ileostomy and insertion of a hand-tooled Teflon band around the ileum. The free ends of the loop were sutured, under tension, to the posterior rectus sheath creating extrinsic compression of the bowel by the tightened loop. After denervation of the rectus, stimulating electrodes were implanted and connected to a transcutaneously activated pulse generator (Medtronic SE-4). Stimulation caused contraction of the muscle segment. As the free ends of the prosthetic sling approach each other, the occlusive band loosens, resulting in free drainage of intestinal contents and reduction in intraluminal pressure of the proximal ileum. Withdrawal of current allows for relaxation and return of the muscle to its resting length; this reoccludes the bowel. At 2 weeks, all dogs were continent to solid matter and all but two were continent to liquids. Two dogs developed wound infections requiring drainage. Signal attenuation across the skin resulted in total uncontrollable continence in two dogs because of an inability to transfer sufficient current to the muscle. Direct probe stimulation by an external pulse generator resulted in drainage in these dogs. Necropsy showed no evidence of bowel ischemia in any of the specimens examined at 2 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)

Vesicle-to-cell protein transfer: insertion of band 3, the erythrocyte anion transporter, into lymphoid cells.

Band 3, the erythrocyte anion transporter, transfers spontaneously between human red cells and model membranes. During incubation of intact erythrocytes with sonicated dimyristoylphosphatidylcholine vesicles, the transporter inserts in functional form and native orientation into the liposome bilayer, with the cytoplasmic segment of the protein contacting the lumen of the vesicle [Newton, A. C., Cook, S. L., & Huestis, W. H. (1983) Biochemistry 22, 6110-6117; Huestis, W. H., & Newton, A. C. (1986) J. Biol. Chem. 261, 16274-16278]. When band 3-vesicle complexes are incubated with erythrocytes whose native band 3 has been inhibited irreversibly, reverse transfer of the protein restores anion transport capacity to the cells [Newton, A. C., Cook, S. L., & Huestis, W. H. (1983) Biochemistry 22, 6110-6117]. Here we report the vesicle-mediated transfer of band 3 to human peripheral blood lymphocytes and to cultured murine lymphoma cells (BL/VL3). Subsequent to incubation with protein-vesicle complexes, both lymphoid cell types exhibit a 2-4-fold increase in the rate of chloride uptake. This enhanced permeability is inhibited greater than or equal to 98% by the exofacial band 3 inhibitor 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid, consistent with right-side-out insertion of functional band 3 into the lymphoid cell membrane.

Le lambeau tendineux triangulaire dorsal inversé, porte ouverte sur l'articulation interphalangienne proximale (IPP)

This dorsal approach allows for a large exposure and provides direct access to the PIP joint. A long triangular tendinous flap with a pedicle based on the insertion of the medial band in dissected from the extensor apparatus and lifted up, leaving the intact lateral bands to slip anteriorally, which exposes perfectly the PIP joint. After joint exposure is achieved and surgery accomplished, this flap is firmly sutured in place and the joint immediately allowed to move. Three cases are presented.

A multi-degree of freedom acoustic lining for noise suppression in broad air ducts

A combination multi-degree of freedom acoustic lining is designed. A given space volume (30 × 37 × 1000 cm3) is properly distributed in different levels. As a result 28-acoustic resonators of the Helmholtz type and two similar triangular chambers are obtained. These resonators are tuned to different frequencies, so that they cover a frequency range from 65 Hz to about 450 Hz.The measured third octave band insertion loss showed a wide band attenuation in the frequency range from 80 Hz to about 600 Hz. When the triangular chambers are filled with loose fibre (jute) as absorbent material, the attenuation of the lining extends to higher frequencies, up to about 2000 Hz. An average insertion loss of more than 20 dB is measured in a wide frequency range.

Leukemia with a novel 4q11q rearrangement

Translocation (4;11)(q21;q23) is characteristic of a distinct acute leukemic syndrome. We report an 8-wk-old male patient with the clinical features ascribed to t(4;11), but with an unusual chromosome rearrangement consisting of an insertion of the 11q23 band into the q21 region of chromosome #4.