Distal Piece Research Articles

A Clinical Case Report: Closed Extraction of a Broken Distal Piece of the Tibial Intramedullary Nail Remaining for 8 Years

Aim: Closed extraction of a broken distal piece of the intramedullary nail is very challenging. We herein report a case of the broken distal piece of the tibial intramedullary nail remaining for 8 years, which was successfully extracted by closed method using a self-made broken nail extractor.
 Case Presentation: A 51-year-old male patient was admitted to our hospital for extraction of the broken distal piece of the tibial intramedullary nail for 8 years. The preoperative X-ray films showed the broken intramedullary nail was cannulated and the outer diameter is 10 mm, larger than the isthmus of the medullary cavity.
 Results: After reaming with Φ 11 mm drill, the self-made broken nail extractor was inserted into the medullary cavity from the nail entry point and passed through the canal of the broken nail, and successfully pulled out the broken nail.
 Conclusion: Our technique is a simple reproducible alternative that has high extraction success rate for broken distal piece of cannulated intramedullary nails.

Self-Made Minimally Invasive Broken Nail Extractor for Distal Broken Segment of Cannulated Intramedullary Nails: One Case Application Report and Literature Review

Introduction: Successful minimally invasive extraction of a broken intramedullary distal piece of the nail is very challenging. We herein report a simple and reproducible technique of extraction of broken cannulated intramedullary nails using a self-made minimally invasive broken nail extractor. Case Presentation: We present a 48-year-old male patient who was admitted to our hospital for internal implant removal, whose right tibial fracture had healed, and a broken intramedullary nail was retained at the distal of the tibial for 12 years. The preoperative X-ray films showed the broken intramedullary nail was cannulated and the outer diameter is 10 mm, larger than the isthmus of the medullary cavity. Results: After reaming with Φ 11 mm drill, the self-made broken nail extractor was inserted into the medullary cavity from the nail entry point and passed through the canal of the broken nail, and successfully pulled out the broken nail. Conclusion: Our technique is a simple, reproducible alternative that has a high extraction success rate for the distal broken segments of cannulated intramedullary nails.

Gastro-retentive drug delivery systems: a review with focus on ϐloating drug delivery systems

Gastro-retentive drug delivery systems (GRDDS) attributes to gastric maintenance time combined with the medication discharge for expanded time has essentially improved patient consistency. Medications for which the chief fundamental site of ingestion is the stomach or the proximal piece of the small digestive tract or have the assimilation issue in the distal piece of the digestive system are reasonable for GRDDS. Orally sustaining or controlling the drug release combined with gastric retention property can avoid recurrent dosing in the case of drugs with short half-lives. GRDDS is also effective in locally treating gastric and duodenal ulcers, including oesophagitis and Helicobacter pylori infections. In this current survey, the physiology of the stomach alongside its motility design, typically called migrating motor complex (MMC), was discussed. Various approaches to GRDDS with a focus on floating drug delivery systems (FDDS) were reviewed. The vacillations in plasma drug focus are limited and portion subordinate unfriendly impacts can be forestalled by FDDS, particularly for the medications with a restricted restorative list. Slow arrival of the medication into the body by means of FDDS limits the counter movement prompting higher medication proficiency. Further, the Advantages, limitations, suitable drug candidates, factors affecting and Future challenges of FDDS were discussed.

Removal of Broken Intramedullary Femoral Nail with Broken Distal Locking Bolt – A Case Report

Non-union after closed femoral interlock nailing is an uncommon complication and occurs when a patient starts early weight-bearing, due to faulty surgical technique or after re-trauma. Removal of broken with broken locking bolt is a difficult and challenging procedure. The present case report deals with a case of the broken intramedullary nail with a broken distal locking bolt. A 30 years male patient was inserted interlocking nail for fracture shaft femur five years back. He presented with pain with instability and inability in weight-bearing after re-trauma. An X-ray revealed a broken nail with a broken distal locking bolt. The far fragment of the broken bolt was engaging bone and nail both and was the main obstacle. His nail with the broken bolt removed and re-nailing did in a single sitting. Steinmannpin (St.pin) was inserted through the distal piece of the nail to push the trapped small screw piece.

Rešavanje retko viđenog gubitka hemodijaliznog katetera tokom njegove zamene - prikaz slučaja

Introduction: In patients with end-stage renal disease (ESRD), permanent hemodialysis catheters are often used by performing percutaneous catheterization to create a permanent vascular access. To the best of our knowledge, no cases with accidental loss of catheter piece during hemodialysis catheter replacement or during its retrieval under scopy has been reported in the literature yet. Case report: It was decided to retrieve the right permanent dialysis catheter of a 54-year-old woman, who had received a temporary dialysis catheter due to the development of catheter site infection in her 3rd permanent catheter (the first two were changed due to thrombosis). Due to excess adhesion in the region, the retrieval of the catheter was complicated, only half of it (proximal piece after cutting into two) was removed, while the distal section slipped and migrated to the right subclavian vein, up to the right atrium. The diagnosis was confirmed by chest radiographs showing that the distal piece of the catheter piece was in the right subclavian vein and right atrium. The catheter piece was retrieved through a minor invasive procedure made possible by scopy without any further complications. Conclusion: Permanent dialysis catheters should ideally be placed under scopy. Also, when the retrieval of a catheter is planned, cutting from any part of the catheter should never be performed.

A single nucleotide polymorphism within Ninjurin 2 is associated with risk of multiple sclerosis

Multiple sclerosis (MS) is a devastating inflammatory disease of the central nervous system (CNS) associated with loss of myelin sheaths. The role of Schwan cells in the remyelination of MS lesions has been documented. However, the detailed steps of this process are unknown. Ninjurin 2 (NINJ2) encodes an adhesion protein with high expression in Schwann cells adjoining the distal piece of injured nerve. Based on the role of this protein in neurite outgrowth, it might participate in the process of nerve regeneration after nerve damage. In the present study, we genotyped two NINJ2 single nucleotide polymorphisms (SNPs) namely rs11833579 and rs3809263 in a population of Iranian patients with MS as well as healthy individuals. The frequency of T allele of the rs3809263 was significantly higher in MS patients compared with healthy subjects (OR (95% CI) = 1.33 (1.08-1.63), adjusted P value = 0.01). TT genotype of this SNP was associated with MS risk compared with CC genotype (OR (95% CI) = 2.22 (1.37-3.57), adjusted P value = 0.009). Moreover, the rs3809263 was associated with MS risk in recessive model (OR (95% CI) = 2.09 (1.33-3.31), adjusted P value = 0.003). There were no significant difference in the alleles and genotypes frequencies of rs11833579 between cases and controls. The current research suggests contribution of NINJ2 in the pathogenesis of MS and warrants further studies for elaboration of the underlying mechanism of such contribution.

Evaluation of the ulnar styloid base on outcome after plate-and-screw fixation of a distal radial fracture: Unrepaired fracture

Background: The impact of an unrepaired fracture of the ulnar styloid base on recuperation after inside obsession of a fracture of the distal piece of the sweep is unverifiable. We assessed a progression of patients with an inside settled fracture of the distal piece of the range to test the theory that there is no distinction in wrist movement or capacity scores between those with an untreated fracture of the ulnar styloid base and those with no ulnar fracture. Methods: Two partners of seventy-six coordinated patients, one with a fracture of the ulnar styloid base and the other with no ulnar fracture, were reflectively investigated by analyzing information assembled in a forthcoming investigation of plate-and-screw obsession of distal outspread fractures. Patients were coordinated for age, sex, AO fracture write, and damage component. The two partners were broke down for contrasts in movement, hold quality, torment, the Gartland and Werley score, the handicaps of the arm, shoulder and hand score, and the Short Form-36 score at six, twelve, and two years postoperatively. In a moment investigation, sixty-four patients with

A Novel Non-operative Protocol for the Acute Management of In-season Acromioclavicular Separations

Objectives:Traditional treatment of acromioclavicular (AC) sprains has been a sling with rest and rehabilitation. We have developed a protocol that uses a static scapular retraction brace (Figure 1) to reduce the displaced upper extremity back to the clavicle. We hypothesized that the brace in combination with oral and injected steroid and a rehabilitation protocol that emphasizes postural restoration, facilitates a more anatomic reduction of the AC joint that quickly eliminates discomfort, allows for more anatomic healing and a rapid return to normal activities in type 1, 2, and 3 AC separations.Methods:Data was prospectively collected and retrospectively reviewed on all collegiate football AC separations at an NCAA division I university. Data included treatment, the number of practices missed, the number of games missed, and time to full return to play. Inclusion criteria were all consecutive in-season Type I-III AC separations sustained during football activities that requiring medical attention. Exclusion criteria include fractures, glenohumeral dislocations, rotator cuff tears, nerve injuries, other concomitant shoulder injuries, and injuries sustained during the last game of the season. The end points measured were number of games missed and time to full return to play.Results:During seven football seasons (2008-2014), 56 acromioclavicular separations occurred. Fifty-two (52) AC separations are included in the current study. Full return to play ranged from 0-31 days, with an average 5.7 days to full return to play. On average, athletes missed 0.25 games (range 0-3 games). Quarterbacks missed the most time, and an injury to the quarterback’s throwing shoulder required the most time to return to full play (mean 26 days and 3 games). The return to play in our group of athletes was more rapid and than that reported in the literature.Conclusion:The unique aspect of this protocol is anatomic reduction of the AC joint with the use of a static, three-point brace to pull and rotate the entire forequarter back to the clavicle. It is common in fracture reduction to reduce the distal piece to the proximal segment to achieve anatomic restoration. This principle attempts to do the same. A secondary effect of the static reduction is the diminution of rotator cuff pain due to opening the subacromial space by scapular retraction, thus decreasing pressure on the contused supraspinatus tendon and allowing more rapid resolution of the inflammation. This study represents a specific non-operative protocol for the in-season management of AC injuries to quickly and safely return athletes to play.

Regeneration of the elbow joint in the developing chick embryo recapitulates development

Synovial joints are among the most important structures that give us complex motor abilities as humans. Degenerative joint diseases, such as arthritis, cause loss of normal joint functioning and affect over 40 million people in the USA and approximately 350 million people worldwide. Therapies based on regenerative medicine hold the promise of effectively repairing or replacing damaged joints permanently. Here, for the first time, we introduce a model for synovial joint regeneration utilizing the chick embryo. In this model, a block of tissue that contains the prospective elbow is excised, leaving a window with strips of anterior and posterior tissue intact (window excision, WE). In contrast, we also slice out the same area containing the elbow and the distal piece of the limb is pinned back onto the stump (slice excision, SE). Interestingly, when the elbow is removed via WE, regeneration of the joint takes place, whereas the elbow joint does not regenerate following SE. In order to investigate whether the regeneration response recapitulates the developmental program of forming joints, we used GDF-5 and Autotaxin (Atx) as joint tissue specific markers, and Sox-9 and Col-9 as cartilage markers for in situ hybridization on sections at different time points after WE and SE surgeries. Re-expression of GDF-5 and Atx is observed in the WE samples by 60h after surgery. In contrast, the majority of the samples that underwent SE surgery did not express GDF-5 and Atx. Also, in SE fusion of cartilage elements takes place and the joint interzone does not form. This is indicated by continuous Col-9 expression in SE limbs, whereas Col-9 is downregulated at the joint interzone in the regenerating WE samples. This order and pattern of gene expression observed in regenerates is similar to the development of a joint suggesting that regeneration recapitulates development at the molecular level. This model defines some of the conditions required for inducing joint regeneration in an otherwise nonregenerating environment. This knowledge can be useful for designing new therapeutic approaches for joint loss or for conditions affecting joint integrity in humans.

Comparison of Nitinol Urethral Stent Infections with Indwelling Catheter-Associated Urinary-Tract Infections

To determine the efficacy of intraurethral metal stents in preventing or eradicating urinary-tract infections (UTI) during the management of bladder outlet obstruction (BOO) by comparing the frequency and nature of the infections with indwelling-catheter-associated UTI. The SAS relative-risk test was used to compare the risks of UTI in 76 patients with temporary urethral stents, 60 patients with BOO who had never been catheterized nor stented, and 34 patients with a permanent indwelling urethral catheter (PIUC). Infection was assessed 1 month after placement of the devices. Scanning electron microscopy (SEM) of the proximal and distal pieces of the stents removed from five patients with and five patients without UTI was carried out in a search for predisposing changes on the surfaces. After insertion of the catheter, UTI developed in 79.4% of the patients who originally had sterile urine. However, after insertion of the stent, UTI developed in only 40.9% of the patients with sterile urine. In 21 (44.6%) of the catheterized patients who had infected urine, UTI was eradicated after stent insertion. The SEM analysis of the stents showed that a thick organic layer had formed only on the infected devices but with no sign of erosion. Urinary infection is a significant problem in patients with PIUC but is significantly less frequent and less severe in patients with urethral stents. This advantage of stents over the conventional urethral catheter, in addition to their obvious convenience for the patient, make them good alternatives to reduce the risk of UTI.

SINGLE DISTAL URETER FOR URETEROCYSTOPLASTY: A SAFE FIRST CHOICE TISSUE FOR BLADDER AUGMENTATION

Recently, the use of ureter for bladder augmentation has gained wide acceptance due to a lower complication rate compared to gastrointestinal segments. Unfortunately, the presence of a severely dilated urinary tract implicates loss of function of a renal unit which is often not demonstrated at diagnosis. Conversely, many patients present with 1 or both ureters mildly dilated because of vesicoureteral reflux or functional obstruction. In these cases the use of a single distal ureter seems to be a good option. We report our experience and long-term followup with this subset of patients. Between December 1994 and November 1998, 17 females and 5 males 1.5 to 15.7 years old (mean age 7.2) with a low capacity, poorly compliant bladder underwent ureterocystoplasty with a single distal dilated ureter. Diagnosis included myelomeningocele in 13 cases, central neurogenic bladder in 3, neurogenic nonneurogenic bladder in 2, congenital spinal cord injury in 2, sacral agenesis in 1 and giant sacral teratoma in 1. All but 2 patients complained of recurrent febrile urinary tract infections. Variable degrees of hydronephrosis were observed in all patients. Vesicoureteral reflux was detected in 14 patients and was bilateral in 3. Five patients presented with chronic renal failure. Before surgery 19 patients were on clean intermittent catheterization and prophylactic antibiotics. The segments of ureter used for augmentation ranged from 9 to 14 cm. long (mean 11) and from 0.8 to 2.5 cm. in diameter (mean 1.3). The more distal piece of the ureter was kept unopened to preserve vascular supply. Simultaneous procedures included transureteroureterostomy in all 22 patients, appendicovesicostomy in 10, bladder neck continence procedures in 4 and ureteroneocystostomy in 3. Clinical, radiological and urodynamic evaluation was done 6 months postoperatively and yearly thereafter. Followup ranged from 12 to 60 months (mean 22). Of the patients 19 are dry on clean intermittent catheterization at 4-hour intervals and 6 have had 9 symptomatic urinary tract infections. Hydronephrosis resolved in 14 patients, improved in 6 and remained unchanged in 2. On urodynamics median increase in capacity less than 30 cm. pressure was 177% (range 11% to 560%). When comparing capacity less than 30 cm. water to normal expected capacity for age and weight, 50% of the cases reached or exceeded theoretical capacity while the rest reached 63% to 89% (mean 76%). Long-term complications included persistent reflux in 1 case, deterioration of bladder function without clinical impairment in 1 and spontaneous perforation of the ureteral patch in 1 requiring colocystoplasty. Although increase in bladder capacity is not always optimal with the use of a distal dilated ureter, it is good enough to ensure a good clinical outcome and allow an adequate catheterization interval with a low complication rate in the long term, thus avoiding use of a piece of gut or stomach to perform bladder augmentation in nearly all patients.

Single distal ureter for ureterocystoplasty: a safe first choice tissue for bladder augmentation.

Recently, the use of ureter for bladder augmentation has gained wide acceptance due to a lower complication rate compared to gastrointestinal segments. Unfortunately, the presence of a severely dilated urinary tract implicates loss of function of a renal unit which is often not demonstrated at diagnosis. Conversely, many patients present with 1 or both ureters mildly dilated because of vesicoureteral reflux or functional obstruction. In these cases the use of a single distal ureter seems to be a good option. We report our experience and long-term followup with this subset of patients. Between December 1994 and November 1998, 17 females and 5 males 1.5 to 15.7 years old (mean age 7.2) with a low capacity, poorly compliant bladder underwent ureterocystoplasty with a single distal dilated ureter. Diagnosis included myelomeningocele in 13 cases, central neurogenic bladder in 3, neurogenic nonneurogenic bladder in 2, congenital spinal cord injury in 2, sacral agenesis in 1 and giant sacral teratoma in 1. All but 2 patients complained of recurrent febrile urinary tract infections. Variable degrees of hydronephrosis were observed in all patients. Vesicoureteral reflux was detected in 14 patients and was bilateral in 3. Five patients presented with chronic renal failure. Before surgery 19 patients were on clean intermittent catheterization and prophylactic antibiotics. The segments of ureter used for augmentation ranged from 9 to 14 cm. long (mean 11) and from 0.8 to 2.5 cm. in diameter (mean 1.3). The more distal piece of the ureter was kept unopened to preserve vascular supply. Simultaneous procedures included transureteroureterostomy in all 22 patients, appendicovesicostomy in 10, bladder neck continence procedures in 4 and ureteroneocystostomy in 3. Clinical, radiological and urodynamic evaluation was done 6 months postoperatively and yearly thereafter. Followup ranged from 12 to 60 months (mean 22). Of the patients 19 are dry on clean intermittent catheterization at 4-hour intervals and 6 have had 9 symptomatic urinary tract infections. Hydronephrosis resolved in 14 patients, improved in 6 and remained unchanged in 2. On urodynamics median increase in capacity less than 30 cm. pressure was 177% (range 11% to 560%). When comparing capacity less than 30 cm. water to normal expected capacity for age and weight, 50% of the cases reached or exceeded theoretical capacity while the rest reached 63% to 89% (mean 76%). Long-term complications included persistent reflux in 1 case, deterioration of bladder function without clinical impairment in 1 and spontaneous perforation of the ureteral patch in 1 requiring colocystoplasty. Although increase in bladder capacity is not always optimal with the use of a distal dilated ureter, it is good enough to ensure a good clinical outcome and allow an adequate catheterization interval with a low complication rate in the long term, thus avoiding use of a piece of gut or stomach to perform bladder augmentation in nearly all patients.

Experience with Bailey-Dubow rodding in children with osteogenesis imperfecta.

The current report presents our experience with the use of Bailey-Dubow elongation rods in children with osteogenesis imperfecta. 63 patients with osteogenesis imperfecta underwent a total of 186 primary intramedullary fixations with Bailey-Dubow rods during period 1984-1996. Most of them were inserted into the femur (54.3 %), followed by the tibia (38.2%) and the humerus (7.9%). Patients' age at operation ranged from 1-12 years and treatment-period varied from 1-10 years. Insertion into the femur showed the lowest complication rate (21.0%). Patients either suffered from knee-joint migration of the distal nail (3.9%), proximal nail migration (7.9%), detached T-pieces from the sleeve (7.9%) or chronical nail infection (1.0%). Complication rate after tibia rodding was markedly higher (52.1%). Knee joint migration appeared in 8.5% and the distal piece of the rod migrated proximally in 38.0%, in 31.0% accompanied by recurrent antecurve deformity. Growth arrest and no elongation occurred in 5.6%. Results after humerus operation were by far least satisfying. None of the nails elongated adequately. 8 of the 14 Bailey-Dubow rods (57.1 %) required reoperation caused by migration and chronic nail infection, whereas reoperation rates amounted to 17.8% after femur and 29.6% after tibia insertion. However, just one refracture happened after adequate trauma (road accident), so that an extraordinary success of fracture prevention has to be scored. We concluded that the use of Bailey-Dubow rods in early childhood can be recommended for the femur, whereas insertion into the tibia or humerus is associated with a considerable complication rate.

Apical and Distal Pieces of Aged Potato Tubers Respond Differently to Paclobutrazol

The influence of paclobutrazol, an inhibitor of GA synthesis, on kindertuber formation was studied using 13.5-month-old `Russet Burbank' potato (Solanum tuberosum) tubers. Suberized apical and distal tuber pieces of equal weight were sprayed daily with distilled water (control), 0.001 and 0.01 mg paclobutrazol/liter with or without 2.5 mg kinetin/liter, and 2.5 mg kinetin/liter alone. The tuber pieces were held in the dark (20C) and harvested 8, 16, and 22 days after the first treatment. Only sprouts developed from control apical piece eyes after 22 days. There was an average of 3.6 sprouts/eye, which, in total, weighed 735 mg. Sprouts (2.4/eye) from treated apical piece eyes averaged 46 mg. By 22 days, 0.001 mg paclobutrazol/liter plus kinetin applied to apical pieces resulted in the most kindertubers, 1.9/eye. The largest kindertubers (1.2 g) were produced from apical pieces treated with 0.001 mg paclobutrazol/liter. At each harvest and regardless of treatment, distal tuber pieces produced larger sprouts and more sprouts per eye than apical pieces. Kindertubers developed from distal piece eyes only with the paclobutrazol plus kinetin treatments. Distal eyes produced half as many kindertubers as apical eyes treated similarly. Apical pieces treated with kinetin alone produced fewer sprouts than control pieces, and fewer tubers than paclobutrazol-treated pieces. Sprout weight per eye of kinetin-treated apical pieces was one-third that produced by control pieces and 5.1-fold greater than that of paclobutrazol-treated pieces. A similar trend was observed with sprout weight from distal eyes. Results suggest lowered GA levels are involved in kindertuber formation on aged potato tubers, and GA content or metabolism of distal pieces is unlike that of apical pieces. Distal tuber pieces do not form kindertubers as readily as apical pieces.

On the failure of sutures of ureterovesical anastomosis

The indices of blood pressure in intramural vessels of the ureter before and after dressing, of vesical vessels are presented. The investigations are performed on 15 dogs in experiment and in 15 patients in resection of the urinary bladder with ureterocystoanastomosis and in 2 patients in ureterocutaneostomy as to the urinary bladder cancer. One patient died because of the failure of sutures of ureterocystoanastomosis as a result of ureter necrosis in suture, and one died after ureterocutaneostomy as a result of ureter distal piece necrosis. It is stated that hemocircular disorders occur in intramural vessels of a terminal part of the ureter after dressing of vesical vessels.

Proposition pour une arthroplastie digitale: Etude critique des premiers résultats

In view of the results of Swanson implants, particularly the long-term course of silicone implants, the authors studied and developed semi-constrained sliding arthroplasty designed for metacarpo-phalangeal and proximal interphalangeal joints. The preliminary study on bones and then on cadaver hands and finally on the knee of the rabbit allowed the design and experimentation of a prototype which led to the creation of a semi-constrained arthroplasty for which the elastic diaphyseal anchoring is ensured without cement and which possesses sliding surfaces composed of a metallic (proximal piece)--polyethylene (distal piece) interface. We therefore describe the principles of functioning of this arthroplasty, its technique of insertion, dorsal trans-tendon incision, its accessory (drill for diaphyseal preparations), its anatomical requirements (preservation of the palmar plate and lateral ligaments, bone section) and the postoperative course. To date, 52 arthroplasties have been inserted and we present the results of the first 36 cases for which the follow-up is equal to or a greater than one year (20 MP-16 PIP), indicating the technical modalities according to the various aetiologies (21 cases of rheumatoid arthritis--15 post-traumatic cases) and the complications. The average gain in mobility is 40 degrees with a mean range of movement of 64 degrees. In terms of pain, none of the arthroplasties were associated with pain apart from pain on cold in certain post-traumatic cases. The global and thumb-finger prehensile forces were evaluated to be an average of 90% in relation to the healthy side. Radiological assessment demonstrated fixation of the pieces in every case. Lastly, we discuss the outcome of this arthroplasty and its current indications in relation to the problems of instability essentially occurring in dislocated MP joints of rheumatoid arthritis.

Movement of choline acetyltransferase in axons disconnected from their cell bodies.

1. Phrenic nerves of rats were cut out and divided into two parts of equal length, one proximal and one distal. The activity of choline acetyltransferase of the two pieces was estimated. Four groups of rats were studied: (1) normal rats, and rats in which 3 days earlier, (2) the right nerve had been cut in the uppermost part of the thorax, (3) a ligature had been tied round the right nerve just above the diaphragm, and (4) these two procedures had been combined.2. In normal rats the activity of the enzyme was about the same in proximal and distal pieces. Ligation of the nerve caused an increase of the activity, of about 50%, in the distal but not in the proximal segment.3. After section of the nerve the activity below the section was 18% of normal in the proximal, and 9% in the distal piece.4. When the nerve was both cut and tied the activity decreased to the same level in both pieces, and this was about the level of the proximal piece after mere section of the nerve.5. It is concluded that choline acetyltransferase can move for some time along the axons to the nerve terminals even when the connexion with the soma has been interrupted.

MODIFICATION OF ABNORMAL GAMETIC RATIOS IN DROSOPHILA. I. EVIDENCE FOR AN INFLUENCE OF Y CHROMOSOMES AND MAJOR AUTOSOMES ON GAMETIC RATIOS FROM BAR-STONE TRANSLOCATION MALES

IF one considers the meiotic behavior of two pairs of non-homologous chromosomes, designating one pair A and A’ and the other pair B and B’, then it is expected that A will separate from A’ and B from B’ and that, following a random assortment of the two pairs of chromosomes, four gametic types (AB, A’B’, AB’ and A’B) will be produced with, under ordinary circumstances, equal frequency. NOVITSKI and I. SANDLER (1957) reported a case in Drosophila melanogaster in which they showed that, despite the absence of evidence for departures from regular separation and random assortment in their experiments, certain gametic types were, nonetheless, recovered appreciably more frequently than others. They studied the kinds of gametes produced by Drosophila males carrying the Bar translocation of STONE, T ( 1 ;4) Bs, where A or XD represents the large distal piece of a broken X chromosome attached to the centric piece of a broken fourth chromosome, and A’ or IV a normal fourth chromosome, and where B or Xp represents the proximal centric piece of the broken X chromosome, marked with the mutant Bar, and having the remaining acentric piece of the broken fourth chromosome attached to its free end, and B’ or Y a normal Y chromosome (Figure 1 ) . The relative frequencies of the four gametic types, XD + Xp, IV -F Y, XD + Y, and IV 4- Xp, observed in their experiments are given below in row I, and the relative rates of recovery of the members of each homologous pair of chromosomes are given in row 111.

The Lacinia in the Maxilla of the Hymenoptera.*

The maxilla of biting insects consists of six pieces. There is at the proximal end a two segmented cardo ( c ), which articulates the maxilla to the head capsule (Figs. 1 and 2). Attached to the distal end of the cardo there is in the cockroach (Fig. 1) a rhomboidal-shaped piece, the stipes ( s ). The stipes in the locust (Fig. 2) is also rhomboidal in outline but is limited in its articulation to the mesal portion of the cardo. There is borne at the distal end of the stipes in the cockroach a two-segmented, somewhat bent tongue-shaped piece, the galea, ( g ). The galea of the locust is also two-segmented but borne at the distal and lateral margin of the stipes. At the proximal end of the galea against the lateral margin of the stipes, there is a small sclerite, the palpifer ( p ), which bears the five segmented maxillary palpus. The proximal segment of the galea and the palpifer in the locust constitute the lateral margin of the stipes. There is borne at the distal end of the stipes on the mesal side another appendage, which bears three prominent teeth at its distal end. This is the lacinia ( la ). The arrangement of the parts in the maxillae of biting insects is for all practical purposes identical with the above description and the figures of the maxillae of the cockroach and the locust, showing two distal pieces, a lacinia on the mesal side and a galea on the lateral side, with a segmented maxillary palpus attached on or near the lateral margin at the proximal end of the galea, and is characteristic.

OSTEOMA OF THE OUTER SURFACE OF THE ULNA.

Patient. —J. S. H., aged 28, section laborer, when about 10 years of age noticed a small lump on the outer surface, near the lower end of the right ulna, which has slowly yet constantly grown until the present time. He does not remember any traumatism to this part at any time. Description of Tumor. —The tumor itself measures 7½ inches in circumference; its surface is rough and jagged, resembling the cauliflower somewhat in appearance. The radiograph (Fig. 1), which was taken by me before the operation, shows clearly the usual shortening of the shaft of the ulna and the drawing away of its articular surface from the wrist joint. It also shows the peculiar curving of the shafts of both the bones of the forearm, compensating, in part, for this development, and also the malposition of the distal extremity of the ulna. Since the operation the distal piece has