Which is the best position for the remote injection dome using the adjustable expander/prosthesis in breast reconstruction? A comparative study

Breast reconstruction using mammary implants is a routinely performed surgical procedure that gives good aesthetic results with a relatively simple operation for the patients. When an adjustable expander/prosthesis with remote dome is used for reconstruction, the device is filled through an injection dome connected to the implant through a filling tube. The injection dome is usually inserted into a subcutaneous pocket, either in the axillary area or, most frequently, in the lower lateral thoracic area. Sometimes, this location is not well tolerated by the patient because of pain or discomfort in the breast-thoracic area and can give problems related to the distance, which causes kinking of the filling tube. To avoid this inconvenience and because of frequent patient complaints, the authors decided 3 years ago to place the injection dome in a parasternal position and compare this location with the previously used lower lateral thoracic location. Two hundred sixty patients were divided into two groups (130 patients in each group) and evaluated. All patients underwent mammary reconstruction in the authors' department using Becker adjustable implants. In all patients, the injection microdome was used. In group A, the injection microdome was positioned in the lower lateral thoracic area; in group B, the injection microdome was positioned in a parasternal area. Both groups were compared, considering different features such as pain, discomfort, ease of injection, pain during puncture, aesthetic appearance, risk of kinking, and risk of upside-down rotation of the dome. Average follow-up was 1.6 years. Statistical analysis was performed using Pearson's chi-square test regarding the differences in frequency of two features-aesthetic appearance and pain during puncture-between the two groups. The comparisons regarding both aesthetic appearance and pain during puncture did show a significant difference between the two groups, with a value of p < 0.05 in both cases. In the present study, the results showed how the patients had less pain during puncture and a better aesthetic appearance when the microdome was located in the parasternal position instead of the lower lateral thoracic area. Advantages and disadvantages of the locations used are discussed in this article.     

The rigid transparent dome protector: a new dressing for free-tissue transfers and skin grafts

We have presented a transparent, inexpensive, rigid dome that allows a window to the wound, humidity chamber effect to continuously observe difficult skin-grafted wounds or free-tissue transfers allowing constant monitoring by visualization. The dome is inexpensive because it is simply a discarded breast implant package.     

Patellar mechanics during simulated kneeling in the natural and implanted knee

Kneeling is required during daily living for many patients after total knee replacement (TKR), yet many patients have reported that they cannot kneel due to pain, or avoid kneeling due to discomfort, which critically impacts quality of life and perceived success of the TKR procedure. The objective of this study was to evaluate the effect of component design on patellofemoral (PF) mechanics during a kneeling activity. A computational model to predict natural and implanted PF kinematics and bone strains after kneeling was developed and kinematics were validated with experimental cadaveric studies. PF joint kinematics and patellar bone strains were compared for implants with dome, medialized dome, and anatomic components. Due to the less conforming nature of the designs, change in sagittal plane tilt as a result of kneeling at 90° knee flexion was approximately twice as large for the medialized-dome and dome implants as the natural case or anatomic implant, which may result in additional stretching of the quadriceps. All implanted cases resulted in substantial increases in bone strains compared with the natural knee, but increased strains in different regions. The anatomic patella demonstrated increased strains inferiorly, while the dome and medialized dome showed increases centrally. An understanding of the effect of implant design on patellar mechanics during kneeling may ultimately provide guidance to component designs that reduces the likelihood of knee pain and patellar fracture during kneeling.     

Tissue expander injection dome leakage

Injection dome leakage was found to be the cause for partial disappearance of the saline solution injected into some tissue expanders. When the injection domes of 22 consecutively removed tissue expanders were checked, we found that the average leakage pressure of these was 32 mmHg, with a range of 8 to 110 mmHg. When the patients were lying on their expanders, the weight of the corresponding body part caused intraluminal pressures of up to 90 mmHg in their expanders. Following removal of the expanders, the total leakage was calculated quantitatively and found to be maximally over 50 percent of the injected volume in some instances. The leakage flow through the injection dome in seven consecutively removed expanders was checked at pressures of 25, 50, and 75 mmHg over 30 minutes and was found to be slow. The possibility of injection dome leakage should be kept in mind, however, as a potential complication under unfavorable conditions. At the same time, we want to emphasize that in most instances tissue expanders function quite well and in predictable ways.     

Differences in lectin binding patterns of normal human endometrium between proliferative and secretory phases

Summary The biological fate of a bovine collagen implant (Zyderm Collagen Implant ZCI), injected subcutaneously into rats, was studied by the immunoperoxidase technique using specific antibodies against the bovine implant and against types I, III, IV, V collagens, fibronectin and elastin. The implant remained in the animals until the end of the experiment (90 days), with no visible modification, as demonstrated by immunoperoxidase labelling and scanning electron microscopy. A slight inflammatory reaction was visible around the implant 24 h after injection and within the implant 3 days after injection. Fibroblast invasion began 7 days after injection. The chronology of the deposition in the implant of the host (rat) extracellular matrix components was as follows: by 24 h after injection, fibronectin was observed throughout the implant; types I and V collagens appeared on the 7th day, and, in contrast to surrounding connective tissue, type V collage labelling was obtained without acid pretreatment of the section. Types III and IV collagens were detected inside the implant only 30 days after injection. At the end of the experiment (90 days), there was abundant types I and V collagens after fibroblast migration, and abundant type IV collagen demonstrating an important vascularization. No elastic fibres could be detected inside the implant but they appeared as a dense network around the implant in host connective tissue.     

Importance of maintaining the basic stress pathway above the acetabular dome during acetabular reconstruction

The basic stress pathway above the acetabular dome is important for the maintenance of implant stability in press-fit acetabular reconstruction of total hip arthroplasty. However, information on the basic stress pathway and its impact factors remains unclear. The objective of this study was to investigate the effects of the orientations and positions of the acetabular component on the basic stress pathway. The basic stress pathway above the acetabular dome was defined as two parts: 3D basic trabecular bone stress distribution and quantified basic cortical bone stress level, using two subject-specific finite element normal hip models. The effects were then analysed by generating 32 reconstructed acetabular cases with different cup abduction and anteversion angles within a range of 35–50° and 10–25°, respectively, and 12 cases with different hip centre heights within a range of 0–15 mm above the acetabular dome. The 3D trabecular stress distribution decreased remarkably in all cases, while the 80% of the basic cortical bone stress level was maintained in cases when the acetabular component was positioned at 10° or 15° anteversion and 40° or 45° abduction angles. The basic stress pathway above the acetabular dome was disturbed when the superior displacement of the hip centre exceeded 5 mm above the anatomical hip centre. Positioning the acetabular component correctly contributes to maintain the stress balance between the acetabular cup and the bone during acetabular reconstruction, thus helping restore the normal hip biomechanics and preserve the stability of the implants.     

Estrus and pregnancy rates following synchronization with chronolone intravaginal sponge or norgestomet ear implant in cycling ewes

Two experiments were conducted to evaluate the efficacy of a 3-mg ear implant of norgestomet, left in situ for 10 days, in conjunction with a single injection of 1.5 mg norgestomet and 0.5 mg estradiol valerate (EV) for controlling fertile estrus in the ewe. This treatment regime was compared with a 20-mg cronolone impregnated, intravaginal sponge left in situ for 14 days (Experiment 1) and a modification of the cronolone-sponge-treatment to include a single injection of 1.5 mg norgestomet and 0.5 mg EV (Experiment 2). The percentage of ewes synchronized was not significantly affected by progestin treatment (Experiment 1-cronolone pessary alone, 96%; norgestomet implant and injection of norgestomet and EV, 92%; Experiment 2-cronolone pessary + injection of norgestomet and EV, 84%; Norgestomet implant + injection of norgestomet and EV, 96%). In Experiment 1, the first service pregnancy rate (pregnant of ewes mated) of 80% for cronolone-treated ewes was significantly higher than the 59% observed in norgestomet-treated ewes (P<.05). In Experiment 2, no significant differences were observed in pregnancy rates between the two treatment groups (Cronolone, 57%; Norgestomet, 65%).     

A Model of Flowering in Chrysanthemum

A mathematical model of flowering in Chrysanthemum morifoliumRamat. is described which may be used to predict quantitiessuch as the number of primordia initiated by the apex, plastochronduration and apical dome mass before, during and after the transformationof the apical meristem from vegetative to reproductive development.The model assumes that primordial initiation is regulated byan inhibitor present in the apical dome. Within each plastochronthe apical dome grows exponentially, and the inhibitor concentrationdeclines through chemical decay and dilution. When the inhibitorconcentration falls to a critical level a new primordium isinitiated. There is instantaneous production of inhibitor, anda decrease in dome mass corresponding to the mass of the newprimordium. The process continues until the apical dome attainsa particular mass when the first bract primordium is produced.Subsequent primordia compete with the apical dome for substrates,and the specific growth rate of the dome declines with successiveplastochrons. Eventually, the net mass of the dome starts todecline until it is entirely consumed in the production of floralprimordia. Chrysanthemum morifoliumRamat, flowering, primordial initiation     

Synchronization of estrus in beef heifers with a norgestomet implant and prostaglandin F2alpha

In a 5-year study (1973-1977), 281 cycling beef heifers were treated with a 7-day norgestomet (SC21009) ear implant and an intramuscular injection of prostaglandin F(2alpha) (PGF(2alpha)) at the time of implant removal or 24 hr before implant removal. Percentages of heifers in estrus by 36, 48, 60, 72, and 120 hr after implant removal were 32.4, 52.7, 71.6, 80.1, and 93.2, respectively. Onset of estrus occurred an average of 49.8 +/- 4.7 hr after treatment. Percentages of heifers in estrus 36 hr after treatment were 5.7 and 51.7 for those with a corpus luteum and those without a corpus luteum (or determined regressing by palpation) at implant removal, respectively. When PGF(2alpha) was injected 24 hr before implant removal, 55% of the heifers were in estrus by 36 hr after implant removal compared to 30% when PGF(2alpha) was injected at the time of implant removal; however, by 60 hr after implant removal the difference was 76% vs. 71%. First-service conception rates for synchronized and nonsynchronized heifers were 62.2% and 59.6%, respectively. During 1976 and 1977 heifers were checked for estrus every 4 hr and inseminated 2, 6, 10, 14, 18, 22, 26, or 30 hr after first detected to be in standing estrus. Conception rate was not significantly affected by time of insemination but tended to be higher for heifers bred 26 and 30 hr after first being detected in standing estrus (78.9% and 70.0% vs. average 59.2%). Treatment with a 7-day norgestomet implant plus a single injection of PGF(2alpha) 24 hr before or at implant removal appears to be a practical technique for synchronizing estrus in cycling heifers without affecting conception.     

Plasma hormone levels and reproductive behaviour in anoestrous ewes after treatment with progesterone and PMSG

Plasma progesterone and gonadotrophin levels were studied in anoestrous ewes treated during June or July with a subcutaneous progesterone implant and/or an injection of oestradiol or PMSG. Of 32 ewes treated with progesterone during July, 9 showed a gonadotrophin surge after removal of the implant, and 10 ewes showed oestrous behaviour during the following 4 days. Six ewes conceived at this induced oestrous. Progesterone treatment during June was much less effective, with only 2 of 19 treated ewes showing a gonadotrophin surg and oestrous behaviour. Administration of PMSG at the time of implant removal in the June experiment was followed by a gonadotrophin surge and oestrous behaviour in 18 of 19 ewes, and 15 ewes conceived at the induced oestrus. An injection of PMSG, without progesterone pretreatment, stimulated a gonadotrophin surge and ovulation, but did not result in oestrous behaviour. The treatments employed appeared to initiate cyclic ovarian activity in the July experiment, but not in the June experiment.     

Stereoselective behavior of a novel biodegradable racemic ketoprofen injectable implant in rats

The stereoselectivity of release of ketoprofen (KET) enantiomers from a biodegradable injectable implant containing racemic KET (rac-KET) was investigated in vivo. A pre-column chiral derivatization RP-HPLC method was employed to assay diastereoisomeric derivatives of R- and S-KET. The rac-KET injectable implant, once injected subcutaneously in rats, produced long-lasting plasma levels of S-KET, which were always greater than those of R-KET. The difference in enantiomer concentration was to be related to stereoselective release, due to stereoselective interaction between D,L-PLG in the implant and KET enantiomers, as well as the chiral inversion of KET in vivo. The rac-KET injectable implant provided the sustained release of S-KET with effective plasma levels maintained for about 8 wk after a single injection.     

Morphological changes in theSaimiri sciureus ovarian follicles as detected by laparoscopy

Over 600 laparoscopic examinations of the ovaries inSaimiri sciureus were made following an ovulation induction regime. Examinations were made 10 to 16 hours after the last injection and again 24 hours after the first examination. The preovulatory follicles had clear gelatinous domes and the indentation of the dome was found to be characteristic of post ovulation. Slight morphological changes noted over a 6 hour period of time made it easy to diagnose ovulation in this species.     

The prosicular stage of Rhabdopleura (Pterobranchia: Hemichordata)

After settling, the larva of Rhabdopleura surrounds itself with a collagenous dome. Later, the zooid breaks through the wall of the dome and builds the horizontal tube part of the coenecium on to the dome.
The dome is a layered structure, unknown in other parts of the coenecium. whereas the horizontal tube is made up of rings in the classical manner of the adult coenecium. The construction of these two parts is different. The techniques used to reinforce the horizontal tube show a marked similarity to the cortical bandages recently described in the fossil graptolites, and give support to the claim that they are ancestral to Rhabdopleura. There are two sorts of early horizontal tube, one is a straight tube, and the other is longer and coiled. The hole in the dome through which the zooid emerges to build the horizontal tube is probably produced by a chemical boring of the zooid, and supports the hypothesis that the zooids can bore holes in shells and corals.     

ON THE MECHANISM OF DECUSSATE PHYLLOTAXIS: BIOPHYSICAL STUDIES ON THE TUNICA LAYER OF VINCA MAJOR

Phyllotaxis theory typically assumes that an acropetal influence from recently formed leaves acts on the apical dome to initiate new leaves. Biophysical theory postulates that established plant organs elongate because their primary walls, particularly those in the organ surface layer, are transversely reinforced by cellulose to give the organ overall hoop reinforcement. These two postulates are combined here in a biophysical theory for phyllotaxis. The essential acropetal influence from young leaves is proposed to be the stretching of the adjacent dome tissue by the growth of leaf bases. Cytoskeletal responses on the dome produce reinforcement patterns which initiate new hoop reinforced leaves. Growth of these leaves remodels the dome for the next round of organs. Data pertinent to this theory are presented here for Vinca major. The surface (tunica) layer of the apical dome was isolated by paradermal cuts. Using polarized light, the cellulose alignment in this surface layer was determined, cell by cell, for various stages of the plastochron. The growing dome is typically elliptical, with the major axis shifting by 90° during each plastochron. The periphery of the dome always has cellulose oriented parallel to its margin; the central region, when the major axis is pronounced, has reinforcement normal to this axis. During the plastochron this reinforcement pattern is modified, by plausible biophysical mechanisms, to account for the three major activities of the dome: 1) production of a hoop-reinforced leaf at each end of the ellipse, 2) formation of a hoop-reinforced stem segment, 3) revision of dome structure to produce the same initial reinforcement pattern as at the start of the plastochron, but at 90°.     

Mouse bladder wall injection

Mouse bladder wall injection is a useful technique to orthotopically study bladder phenomena, including stem cell, smooth muscle, and cancer biology. Before starting injections, the surgical area must be cleaned with soap and water and antiseptic solution. Surgical equipment must be sterilized before use and between each animal. Each mouse is placed under inhaled isoflurane anesthesia (2-5% for induction, 1-3% for maintenance) and its bladder exposed by making a midline abdominal incision with scissors. If the bladder is full, it is partially decompressed by gentle squeezing between two fingers. The cell suspension of interest is intramurally injected into the wall of the bladder dome using a 29 or 30 gauge needle and 1 cc or smaller syringe. The wound is then closed using wound clips and the mouse allowed to recover on a warming pad. Bladder wall injection is a delicate microsurgical technique that can be mastered with practice.     

Synchronization of estrus and ovulation and associated endocrine changes in Bos indicus cows

The effects of 4 estrus synchronization treatments on intervals to and synchrony of estrus and ovulation, on timing of the preovulatory LH surge and associated changes in plasma progesterone, LH, FSH, and 17beta-estradiol (E(2)) were investigated in 48 Bos indicus cows. Treatment 1 consisted of 2 injections of PGF(2alpha) 14 d apart (n = 12); Treatment 2 of a subcutaneous 3-mg norgestomet implant and an intramuscular injection of 3 mg of norgestomet and 5 mg estradiol valerate, with the implant removed 10 d later (n = 12; norgestomet-estradiol); Treatment 3 of norgestomet-estradiol, with a subcutaneous injection of PMSG given at time of implant removal (Day 10; n = 12); and Treatment 4 of norgestomet implant (as for Treatments 2 and 3) inserted for 10 d, with an intramuscular injection of PGF(2alpha) given at the time of implant removal (n = 12). The experiment was conducted in 2 replicates (24 cows/replicate, 6 cows/group). Estrus, ovulation and timing of the preovulatory surge of LH varied less in cows treated with norgestomet-estradiol and PMSG than in cows in Treatments 1 and 4 (P < 0.008). Treatment with PMSG reduced variation in ovulation times and timing of the LH surge in cows treated with norgestomet-estradiol (P < 0.02). Concentrations of E(2) were higher in cows in Treatments 2 and 3 on the final day of treatment and at about 6 h post ovulation compared with cows in Treatments 1 and 4 (P < 0.05). Different methods for synchronizing estrus did not alter sequential endocrine and behavioral changes in relation to the timing of the LH peak, and the results were consistent with current recommendations for insemination times in Bos taurus cattle.     

Correction of experimentally produced vesicoureteric reflux in the piglet by intravesical injection of Teflon.

Vesicoureteric reflux was produced in eight piglets by opening their bladders and slitting the anterior intravesical wall of the ureter. Cystography confirmed the presence of bilateral reflux in six piglets and unilateral reflux in two. Six to eight weeks later the bladder was again opened and Teflon paste injected in the space behind the intravesical ureter, thereby creating a support for the submucosal ureter. Cystography four to six weeks after injection of Teflon paste showed absence of reflux in all animals. Intravenous pyelography showed obstruction at the vesicoureteric junction in only one of the 14 treated ureters and this was later confirmed at necropsy. Animals were followed up from one to six months and then were killed. Gross examination of the vesicoureteric region showed a well circumscribed subureteric Teflon mass of firm consistency, retaining its shape and position at the site of the injection. Histological examination showed encapsulation of the implant by a thin layer of fibrous tissue and a foreign body granulomatous reaction with histiocytes and giant cells within the implant. Hence it is technically feasible to correct experimentally produced vesicoureteric reflux in the piglet by intravesical injection of Teflon paste--a relatively inert material. It may now be possible to treat vesicoureteric reflux in man by endoscopic injection of Teflon behind the intravesical ureter.     

High-pressure injection of silicone gel into an axilla--a complication of closed compression capsulotomy of the breast. Case report.

A case is reported in which a closed compression capsulotomy for fibrous capsular contracture was followed by rupture of the implant bag with the immediate appearance of silicone gel in the axilla. A possible mechanism, analogous to that of high-pressure injection injuries of the hands, is hypothesized.     

THE SHOOT APICAL ONTOGENY OF THE PICEA ABIES SEEDLING. III. SOME AGE-RELATED ASPECTS OF MORPHOGENESIS

We have extended our previous analyses of growth in shoot apices of Picea abies seedlings. Quantification of apical dome volume changes, more detailed analysis of the subapical caulis profile, and of the vertical distance from the base of the dome to the nth primordium, all as functions of age, revealed the dynamics of various growth variables. As seedlings age from 10 to 136 days, apical dome volume increases about 30-fold, plastochron duration declines from 31 h to about 5 h, height of primordial internodes declines from near 10 μm, to only 3.5 μm, and the caulis assumes a distinct neck-and-shoulder profile. Relative volume growth rates for the apical dome as a whole are about twice the base-of-dome values and decline from 36% to 21% per day as age increases to 136 days. Relative growth rates (radial, vertical, and volume) in the caulis change in a complex manner with both plant age and internode number. We also computed the total volume of tissue generated by an apical dome per day including that part invested in increased dome volume. The investment (ϕ) ratio is greater than 20% in the 10-day dome, but declines rapidly to become negative after 136 days. The ϕ ratio controls apical dome volume and hence augurs future growth yield.     

The effect of eCG or estradiol at or after norgestomet removal on follicular dynamics, estrus and ovulation in early post-partum beef cows nursing calves

In post-partum anestrous beef cows suckling calves, neither the choice of hormonal regime to ensure the presence of a healthy dominant follicle at the end of a progestagen treatment nor the optimum hormone to induce estrus and ovulation is clear. Twenty-eight beef cows, in good body condition, 25-30 days post-partum, were assigned to one of four treatments: (i) 3mg norgestomet (N) implant with 5mg estradiol valerate (EDV) and 3mg N injection at the time of insertion (Crestar) for 5 days followed by 600 IU eCG at the time of implant removal; (ii) Crestar for 5 days as in (i) followed by 0.75 mg estradiol benzoate (EDB) 24h later; (iii) Crestar for 9 days followed by 600 IU eCG at the time of implant removal; and (iv) Crestar for 9 days followed by 0.75 mg EDB 24h later. Ovarian scanning was preformed from 4 days before implant insertion until ovulation and 4 days postovulation to detect the CL. Daily blood samples were collected from day 20 post-partum until second ovulation for FSH and E(2) assay. Data were analyzed using analysis of variance. There was no effect of the stage of follicle wave at the time of implant insertion on interval to new follicle wave emergence (range 1-7 days; mean 4.7 days). FSH concentrations were decreased to 5.9+/-2.0 and 7.7+/-1.1 ng/ml for pre- and post-selection cows 1 day after start of treatment; thereafter, they increased on Day 2 to 7.9+/-2.0 and 11.0+/-1.1 ng/ml and on Day 3 to 10.3+/-2.7 and 11.4+/-1.7 ng/ml for pre- and post-selection cows, respectively, despite high-estradiol concentrations at that time. There was no effect of treatment on the interval from implant removal to ovulation (3.2-4.0 days) or on the number of cows detected in estrus (26 of 27 cows). The size of the ovulatory follicle in cows given 0.75 mg EDB 24h post implant removal was decreased in animals at the pre-selection stage (12.2+/-0.1mm) of the follicle wave compared with those at the post-selection stage (15.3+/-0.9 mm) at implant removal. Cows given 600 IU eCG at the pre-selection phase of follicular growth had multiple ovulations (4.0+/-1.1). Cows given EDV at the start of a 5-day implant period had higher estradiol concentrations before and on the day of implant removal than those given EDV at the start of a 9-day implant period. The injection of 0.75 mg EDB 1 day after implant removal tended to increase concentrations of estradiol one day later. In conclusion, 5mg EDV and 3mg N at insertion of a 3mg N implant resulted in variable new follicle wave emergence 1-7 days later in post-partum beef cows nursing calves (22 of 27); both eCG and EDB were equally effective at inducing estrus after implant removal in cows in good BCS, but eCG resulted in a significant increase in ovulation rate in cows treated before dominant follicle selection.