Sponge Treatment Research Articles

Vaginal Histological Changes after Using Intravaginal Sponges for Oestrous Synchronization in Anoestrous Ewes

To characterize the histological and cytological vaginal changes generated by the use of intravaginal sponge (IS) applied in oestrous synchronization treatments in ewes during mid-non-breeding season. Thirty-five multiparous ewes were allocated to three experimental groups according to the moment in which the samples were taken: (i) ewes treated with IS containing 60 mg of medroxyprogesterone acetate for 14 days, sampled the day of IS removal (group ISR; n = 10), (ii) or after sponge removal at time of oestrus or 72 h after removal (group AR; n = 14) and (iii) ewes without sponge treatment that were sampled at the day of IS removal of the other groups (group CG; n = 11). Vaginal biopsies and cytological samples were taken from the anterior vaginal fornix area. The vagina of the CG group had a stratified squamous epithelium with a moderate degree of cellular infiltration with lymphocytes and plasma cells in the lamina propia. Treated ewes (ISR and AR) had epithelial hyperplasia and hypertrophy. ISR ewes had haemorrhage and perivascular infiltrate and an increased number of epithelial cells, neutrophils, macrophages and erythrocytes at IS removal. The use of IS generated histological and cytological alterations in the vaginal wall when used for oestrous synchronization in anoestrous ewes.

The Mechanical Properties of Compact Titanium Produced from Titanium Hydride Powders Using Self-Propagating High-Temperature Synthesis

The mechanical properties of titanium compacts from titanium hydride powders produced by conventional heat treatment of titanium sponge in hydrogen and by self-propagating high-temperature synthesis are compared. It is shown that the strength and plastic characteristics of titanium from powders hydrogenated by self-propagating high-temperature synthesis are not worse and sometimes even better than those of titanium produced in the same way from conventional hydride powders. It is determined that titanium sintered from powders hydrogenated by self-propagating high-temperature synthesis commonly contains more oxygen compared to titanium sintered from powders hydrogenated by heat treatment in hydrogen. However, titanium made of powders from self-propagating high-temperature synthesis contains a lower content of other impurities decreasing its plasticity. It is assumed that the yield stress, ultimate strength, and plastic characteristics of titanium sintered from powders produced by different methods are determined by the quantitative and qualitative composition of impurities.

Endoluminal Vacuum Therapy for Iatrogenic Perforation of the Proximal Oesophagus

Iatrogenic perforation of the upper gastrointestinal tract is one of the most serious complications of upper gastrointestinal endoscopy, with high rates of morbidity and mortality. Treatment is challenging because stent placement or surgical repair of the perforation in this area is often impossible. We report on two cases of iatrogenic perforations of the very proximal oesophagus and distal hypopharynx which could be successfully closed by using an endoluminal vacuum sponge treatment for 5 days. Thus, the endoluminal vacuum therapy may be a useful alternative to surgery in such cases of difficultly managable perforations of the upper oesophagus.

The timing of oestrus, the preovulatory LH surge and ovulation in Blanca Andaluza goats synchronised by intravaginal progestagen sponge treatment is modified by season but not by body condition score

The aim of this study was to determine whether a seasonal pattern of reproductive events is followed after synchronisation by intravaginal progestagen sponge treatment in female Blanca Andaluza goats, and whether the timing of these events is affected by body condition score (BCS). During seasonal anoestrus (March), and again during the breeding season (November), the same 32 does were distributed into four subgroups according to their BCS: ≤2.25, =2.50, =2.75, and ≥3.00 (n=8 in all cases). They were then synchronised using a commercial intravaginal sponge treatment. Every 4h over the 72h following sponge removal, oestrous activity, the LH concentration and each doe's number of follicles were followed by transrectal ultrasonography. The does synchronised during seasonal anoestrus produced more follicles than those synchronised during the breeding season (P<0.01). The time elapsed between sponge removal and the onset of oestrus, the LH surge and time of ovulation, was also shorter in these does (P<0.001). The BCS only modified the number of follicles present in the ovary just before ovulation; this number was significantly lower in the =2.50 BCS subgroup than in the other subgroups (P<0.05). The present results show that the time to ovulation, and all events around it, are modified by the season in which Blanca Andaluza does are synchronised, but not by BCS.

Transrectal negative pressure sponge treatment of full‐thickness rectal perforation

Transrectal negative pressure sponge treatment of full‐thickness rectal perforation

Blue-violet light-emitting diode irradiation in combination with hemostatic gelatin sponge (Spongel) application ameliorates immediate socket bleeding in patients taking warfarin

The control of bleeding after tooth extraction is a major concern in patients taking warfarin. Light-emitting diode (LED) irradiation with hemostatic gelatin sponge application was investigated. Patients who took warfarin and required tooth extraction were divided randomly into 3 groups. The first group was irradiated with blue-violet LED after tooth extraction. The second group was treated with a hemostatic gelatin sponge and LED irradiation. The third group was treated with only hemostatic gelatin sponges. Hemostasis was evaluated at 30 seconds after treatment. Less than 30% of the patients achieved hemostasis within 30 seconds in the hemostatic sponge group; approximately 50% of the patients in the simple LED irradiation group achieved hemostasis within 30 seconds; and 86.7% of the patients in the LED and hemostatic sponge combined group achieved hemostasis within 30 seconds, indicating that combined treatment with LED and hemostatic sponges provided a significantly higher hemostasis than in the hemostatic sponge group (P < .01). Blue-violet LED irradiation combined with hemostatic gelatin sponge treatment yielded hemostasis of the extraction socket within 30 seconds without suture in most cases.

Reproductive efficiency of Pelibuey and Romanov × Pelibuey ewes synchronized with synthetic progesterone and low doses of PMSG under a hot environment

Thirty-nine multiparous ewes (19 Pelibuey and 20 Romanov &amp;times; Pelibuey) treated with fluorogestone acetate impregnated intravaginal sponges were used to evaluate the effects of low pregnant mare serum gonadotropin (PMSG) doses and genotype on their reproductive efficiency under heat stress conditions. The sponge treatment lasted for 12 days, and 24 h before sponge removal, ewes of each genotype were injected with 140 or 280 IU of PMSG. Ewes showing estrus were naturally mated twice. Reproductive performance was not affected (P &amp;gt; 0.05) by the dose &amp;times; genotype interaction. All treated ewes presented estrus signs within a 48-h period after sponge removal. Shorter (P &amp;lt; 0.05) estrus interval and higher (P &amp;lt; 0.05) fecundity were observed in ewes treated with 280 IU of PMSG compared to those treated with 140 IU. Pelibuey ewes exhibited shorter (P&amp;nbsp;&amp;lt;&amp;nbsp;0.01) estrus interval and greater (P &amp;lt; 0.01) fertility as compared with Romanov &amp;times; Pelibuey ewes. The response to estrus, gestation length, prolificacy, and percentage of single and multiple lambing were not affected (P &amp;gt;&amp;nbsp; 0.05) by dose or genotype. In conclusion, under heat stress conditions, low PMSG doses as 140 or 280 IU can be used to successfully induce and/or synchronize the estrus in Pelibuey ewes and their crosses with Romanov, regardless of reduced fertility observed in crossed Pelibuey ewes. If a more predictable and compact estrus is required, administration of 280 IU of PMSG is recommended.

Novel Animal Model of Calvarial Defect

Recombinant human bone morphogenetic protein-2 (rhBMP-2) has been shown to be an effective therapy in the acute calvarial defect wound and in calvarial defects complicated by chronic scar. The authors compared the effectiveness of rhBMP-2 with the accepted standard of autologous graft for repair of irradiated calvarial defects. Nineteen adult New Zealand White rabbits underwent subtotal calvariectomy. Four days postoperatively, animals received 15 Gy to their wound. Six weeks postoperatively, scars were débrided and defects reconstructed in one of four groups: empty (n = 3), vehicle (buffer solution/absorbable collagen sponge; n = 3), cryopreserved autograft, (n = 3), or rhBMP-2 repair (rhBMP-2/absorbable collagen sponge, n = 10). Animals underwent computed tomography imaging at 0, 2, 4, and 6 weeks, followed by euthanization and histological analysis. Percent healing was determined and a 4 × 3 mixed model analysis of variance was performed on healing versus treatment group/postoperative time. According to radiopacity, rhBMP-2/sponge and autografts were statistically equivalent, with 99 and 89 percent healing at 6 weeks. Empty and vehicle treatment groups, with 35 and 34 percent healing, were inferior to the rhBMP-2/sponge and autograft groups (p < 0.05). Histologically, bone in the surgical control (autograft) group was less cellular and trabecular than bone formed after rhBMP-2/sponge treatment. rhBMP-2 therapy was as effective in reconstructing calvarial defects in the unfavorable irradiated wound as in the acute, favorable calvarial wound. Compared with cryopreserved autologous graft, rhBMP-2-regenerated bone resulted in equal defect coverage, similar thickness, and greater cellularity. Further studies are necessary to demonstrate the long-term viability and remodeling rhBMP-2/sponge-generated bone.

In vivo osteoinductivity of gelatin β-tri-calcium phosphate sponge and bone morphogenetic protein-2 on an equine third metacarpal bone defect

This study evaluated the therapeutic effects of a gelatin-β-TCP sponge (sponge) incorporating BMP-2 (BMP-2/sponge) on bone regeneration in equines. Six bone defects were created in third metacarpals of five thoroughbred horses, and a total of six treatments were applied in a randomized manner. The treatments were BMP-2/sponge, BMP-2/gelatin hydrogel sheet (sheet), free BMP-2, bFGF/sheet, plain sponge, and plain sheet. The defects were monitored for 16weeks by radiography and then examined by histological analysis. Radiographic evaluation scores of bone regeneration revealed significantly greater bone regeneration of defects treated with BMP-2/sponge than defects treated with plain sponge or BMP-2 sheet (P<0.05). In histological analysis, compact bone was observed over a wide area in the BMP-2/sponge treatment. We concluded that the treatment with BMP-2/sponge accelerated bone regeneration in the equines of this study.

Analysis of the effectiveness of basic fibroblast growth factor treatment on traumatic perforation of the tympanic membrane at different time points

ObjectiveThe aim of this study was to evaluate the effectiveness of basic fibroblast growth factor (bFGF) treatment on traumatic perforation of the tympanic membrane at different time points. Research DesignThis is a prospective clinical study. MethodsPatients with traumatic perforations of the tympanic membrane were given a treatment of gelatin sponge + bFGF at different time intervals of 3 days, 4 to 7 days, 8 to 15 days, and more than 4 weeks after the injury. Healing rate and time of perforation were also observed after 1 month. ResultsIn 147 ears, 144 (98.0%) were healed. The perforation healing rates were 98.6%, 97.6%, 96.3%, and 100%, respectively, at the following time intervals: within 3 days, 4 to 7 days, 8 to 14 days, and 2 to 4 weeks since the injury. This was quite true without any significant difference (P > .05). Meanwhile, in the small perforation healing of 120 ears, the average healing times from admission to perforation within 3 days, 4 to 7 days, and 8 to 14 days after the injury were 7.95 ± 2.07, 6.75 ± 2.67, and 4.18 ± 0.91 days, respectively. No significant difference was found among the 3 groups (P1 < .01). ConclusionTreating traumatic perforation of the tympanic membrane using the bFGF technique at different times of admissions is quite effective.

Characterization of Oestrous Induction Response, Oestrous Duration, Fecundity and Fertility in Awassi Ewes During the Non‐breeding Season Utilizing both CIDR and Intravaginal Sponge Treatments

The aim of this study was to investigate characterization of oestrous response, onset of induced oestrus, oestrous duration, fecundity and fertility in Awassi ewes treatment with intravaginal sponges and Controlled Intravaginal Drug Release (CIDR) devices in combination with pregnant mare serum gonadotropin (PMSG) under local environmental conditions during the non-breeding season. A total of 62 ewes were divided into three groups. Group CIDR (n = 20) was treated with CIDR devices for 12 days and 400 IU PMSG was injected upon removal of the CIDR. For ewes in Group Sponge (SP) (n = 24), 30 mg fluorogestone acetate was administered to the sheep for 12 days and 400 IU PMSG was injected upon withdrawal of the sponge. Group Control (CON) (n = 18) served as a control group and received no treatment. Adult, intact and sexually experienced Awassi rams were introduced to all groups at the time when the intravaginal devices were removed. There were no significant differences in terms of oestrous response (CIDR: 90%, SP: 87.5%), time to onset of oestrus and duration of induced oestrus between the CIDR and SP groups. The oestrous response of treatment groups was significantly greater (p < 0.05) than in the control ewes. There were no significant differences in pregnancy (CIDR: 70%, SP: 70.8%), lambing (CIDR: 85%, SP: 79.2%) and fecundity rates between ewes treated with CIDR and those treated with sponges. However, pregnancy and lambing rates were significantly (p < 0.05) higher in ewes treated with CIDR or sponges when compared with those in the control group. It was concluded that it is possible to induce fertile oestrus, successful pregnancy and lambing with the treatment of either CIDR or intravaginal sponge in combination with PMSG in Awassi ewes during the non-breeding season.

Endo‐sponge treatment of anastomotic leakage after ileo‐anal pouch anastomosis: report of two cases

The endo-sponge was used in two patients in the treatment of anastomotic leakage following ileo-anal J-pouch reconstruction. Recently, local vacuum sponge treatment has shown to be effective to treat contained anastomotic leakage after low anterior anastomosis in rectal cancer patients. Two patients (male, 18 years; female, 40 years) who underwent restorative proctocolectomy for ulcerative colitis developed localized anastomotic leakage without general peritonitis. This was endoscopically managed by transanal placement of an endo-sponge (B. Braun Medical B.V., Melsungen, Germany) after a diverting ileostomy was performed. The sponge was frequently replaced until resolution of the sinus was achieved in 35 and 56 days. Vacuum endo-sponge treatment can help anastomotic leakage after ileo-anal pouch surgery.

Ovsynch synchronization and fixed-time insemination in goats

This study assessed the efficacy of an Ovsynch protocol (vs. the classical cronolone containing vaginal sponge+eCG treatment) to generate fixed-time insemination in goats during the breeding season. Each regimen was applied to 24 Boer goat does. Onset and duration of estrus were determined with an aproned male and follicular development was monitored by ultrasonography. Ovulation and quality of the corpora lutea were established from progesterone concentrations. In 10-11 goats per group, LH concentrations were determined throughout the preovulatory period. Does were inseminated at pre-determined times (16 h after the second GnRH injection and 43 h after sponge removal). Estrus was identified in 96% of the Ovsynch-treated goats (at 49 h after prostaglandin injection) and in 100% of the goats synchronized with sponges (at 37 h after sponge removal). Low progesterone concentrations at the time of AI were observed in 21/24 and 24/24 goats synchronized by Ovsynch and sponges, respectively. Synchronization of the LH surge was tighter following Ovsynch compared to sponge treatment. Kidding rates (at 58 and 46% in the Ovsynch and sponge groups, respectively) and prolificacy (at 1.86 and 1.83 in the Ovsynch- and sponge-treated goats) were similar for both groups, as were the number of ovulations (2.9 and 3.3) and the proportion of does with premature corpus luteum regression (29 and 17%). When excluding does with premature luteal regression and those with low progesterone levels when receiving prostaglandins, kidding rate reached 87.5% (14/16) after Ovsynch. During the breeding season, the Ovsynch protocol may thus be an useful alternative to the sponge-eCG treatment.

Synchronization of follicular wave emergence in the seasonally anestrous ewe: The effects of estradiol with or without medroxyprogesterone acetate

Fertility is often lower in anestrous compared to cyclic ewes, after conventional estrus synchronization. We hypothesized that synchronization of ovarian follicular waves and ovulation could improve fertility at controlled breeding in anestrous ewes. Estradiol-17beta synchronizes follicular waves in cattle. The objectives of the present experiments were to study the effect of an estradiol injection, with or without a 12-d medroxyprogesterone acetate (MAP) sponge treatment, on synchronization of follicular waves and ovulation in anestrous ewes. Twenty ewes received sesame oil (n=8) or estradiol-17beta (350 microg; n=12). Eleven ewes received MAP sponges for 12d and were treated with oil (n=5) or estradiol-17beta (n=6) 6d before sponge removal. Saline (n=6) or eCG (n=6) was subsequently given to separate groups of ewes at sponge removal in the MAP/estradiol-17beta protocol. Estradiol treatment alone produced a peak in serum FSH concentrations (4.73+/-0.53 vs. 2.36+/-0.39 ng/mL for treatment vs. control; mean+/-S.E.M.) after a short-lived (6 h) suppression. Six of twelve ewes given estradiol missed a follicular wave around the time of estradiol injection. Medroxyprogesterone acetate-treated ewes given estradiol had more prolonged suppression of serum FSH concentrations (6-18 h) and a delay in the induced FSH peak (32.3+/-3.3 vs. 17.5+/-0.5 h). Wave emergence was delayed (5.7+/-0.3 vs. 1.4+/-0.7d from the time of estradiol injection), synchronized, and occurred at a predictable time (5-7 vs. 0-4d) compared to ewes given MAP alone. All ewes given eCG ovulated 3-4d after injection; this predictable time of ovulation may be efficacious for AI and embryo transfer.

Treatment of High-flow Priapism with Superselective Transcatheter Embolization in 27 Patients: A Multicenter Study

To evaluate the effectiveness and safety of treatment of high-flow priapism (HFP) with superselective transcatheter embolization at nine university hospitals. Between May 1994 and October 2006, 27 patients underwent superselective embolization of the cavernous artery for HFP. Trauma was apparent in 22 patients, there was self-administered intracavernosal injection for erectile dysfunction in two, and the remaining three did not recall any penile or perineal trauma. The embolic agents used were autologous blood clot (n = 12), gelatin sponge (n = 12), microcoils combined with gelatin sponge (n = 1), polyvinyl alcohol (n = 1), and N-butyl cyanoacrylate (n = 1). Recurrence of priapism and change in erectile function were evaluated during a mean follow-up of 13 months. Differences in results between patients treated with autologous blood clot versus gelatin sponge were statistically analyzed with use of the chi(2) test. In 24 of 27 patients (89%), a single embolization was sufficient for complete resolution of priapism. Repeat embolization was required in two patients (7%), and in the remaining patient (4%), shunt surgery was performed after embolization as a result of HFP coexisting with corporeal venoocclusive dysfunction. Eighteen of 23 patients (78%) who had premorbid normal erectile function showed maintained potency during the follow-up period. There was no significant difference affecting required repeat embolization (P = .537) and change in quality of erection (P = .615) during the follow-up period between the autologous blood clot and gelatin sponge treatment groups. Superselective transcatheter embolization in the treatment of HFP is effective and ensures a high level of preservation of premorbid erectile function.

Effects of Long and Short-Term Progestagen Treatments Combined with PMSG on Oestrus Synchronization and Fertility in Awassi Ewes during the Breeding Season

Synchronization of oestrus has been used to increase reproductive efficiency in most animals, including ewes. The aim of the present study was to compare the effect of the length of a progestagen treatment (12 d vs. 6 d) on synchronization efficiency (oestrus response, time to onset of oestrus and duration of oestrus) and fertility rate using fluorogestone acetate (FGA) progestagen sponge treatment with pregnant mare serum gonadotropin (PMSG) administration applied at different times of sponge removal. Ewes (n = 68) were divided into two groups; long term (LT, n = 33) and short term (ST, n = 35) groups treated with FGA progestagen sponges. At the end of intravaginal sponge treatment period the animals of each group were divided into the 3 subgroups in relation to time of PMSG (300 IU) treatment. PMSG treatment was applied 24 h before sponge removal, at sponge removal and 24 h after sponge removal for LT1 and ST1, LT2 and ST2, and LT3 and ST3, respectively. Each ewe was inseminated intra-cervically twice with skim cow milk-diluted semen (1000 × 106 motile cells/ml) 40 h and 60 h after sponge removal. Non-return rates (NRR-30) were monitored from 12 day after sponge removal to 30 day with the aid of teaser rams. Onsets of oestrus response and oestrus cessation were significantly different (P &lt; 0.05) between the ST and LT treatment groups. Synchronization of oestrus was tighter in LT than ST group. Except for oestrus cessation, other indicators studied were not different in the ST subgroups. In the ST subgroups the oestrus cessation of the ST1 (88.7 ± 15.4 h) was the shortest and differed from ST3 (120.0 ± 14.2 h) (P &lt; 0.05). No statistical difference was observed among all studied indicators for LT groups according to application time of PMSG (P &gt;). The NRR-30 and lambing rate of the ST and LT after timed AI were 35.7% and 31.0% and 32.1% and 28.6%, respectively (P &gt; 0.05).

Does injection of prostaglandin F 2α (PGF 2α) cause ovulation in anestrous Western White Face ewes?

In a previous study in our laboratory, treatment of non-prolific Western White Face (WWF) ewes with PGF 2α and intravaginal sponges containing medroxyprogesterone acetate (MAP) on ∼Day 8 of a cycle (Day 0 = first ovulation of the interovulatory interval) resulted in ovulations during the subsequent 6 days when MAP sponges were in place. Two experiments were performed on WWF ewes during anestrus to allow us to independently examine if such ovulations were due to the direct effects of PGF 2α on the ovary or to the effects of a rapid decrease in serum concentrations of progesterone at PGF 2α-induced luteolysis. Experiment 1: ewes fitted with MAP sponges for 6 days ( n = 12) were injected with PGF 2α ( n = 6; 15 mg im), or saline ( n = 6) on the day of sponge insertion. Experiment 2: ewes received progesterone-releasing subcutaneous implants ( n = 6) or empty implants ( n = 5) for 5 days. Six hours prior to implant removal, all ewes received a MAP sponge, which remained in place for 6 days. Ewes from both experiments underwent ovarian ultrasonography and blood sampling once daily for 6 days before and twice daily for 6 days after sponge insertion. Additional blood samples were collected every 4 h during sponge treatment. Experiment 1: 4–6 (67%) PGF 2α-treated ewes ovulated ∼1.5 days after PGF 2α injection; these ovulations were not preceded by estrus or a preovulatory surge release of LH, and resulted in transient corpora hemorrhagica (CH). The growth phase was longer ( P < 0.05) and the growth rate slower ( P < 0.05) in ovulating versus non-ovulating follicles in PGF 2α-treated ewes. Experiment 2: in ewes given progesterone implants, serum progesterone concentrations reached a peak (1.72 ng/mL; P < 0.001) on the day of implant removal and decreased to basal concentrations (<0.17 ng/mL; P < 0.001) within 24 h of implant removal. No ovulations occurred in either the treated or the control ewes. We concluded that ovulations occurring after PGF 2α injection, in the presence of a MAP sponge, could be due to a direct effect of PGF 2α at the ovarian level, rather than a sudden decline in circulating progesterone concentrations.

Changes in the aerobic vaginal bacterial mucous load and assessment of the susceptibility to antibiotics after treatment with intravaginal sponges in anestrous ewes

The aim of the study was to assess changes in the aerobic vaginal bacteria mucous load at different times following treatment with intravaginal sponges and evaluate the antibiotic susceptibility of bacteria in vitro. Intravaginal sponges impregnated with 60 mg medroxy-progesterone acetate were inserted in 22 Corriedale ewes for a period of 5 days ( n = 6), 9 days ( n = 8) or 13 days ( n = 8), respectively, during the non-breeding season. At sponge withdrawal, all ewes received 350 IU eCG im. Bacterial counts and antibiotic susceptibility studies were performed on the vaginal mucus samples obtained before the introduction of the sponges, at sponge withdrawal, 24 h following sponge withdrawal, and on the day of estrus in the three treatment groups. Nine additional ewes without pretreatment with intravaginal sponges (controls) were induced into estrus by means of the ram effect and their vaginal bacterial load was assessed at estrus. The total numbers of aerobic bacteria in the vaginal flow were not different between the groups at any point in time. The mean colony forming units (×10 3 ml −1) were 1.0 ± 0.2 on the day of intravaginal sponge insertion, increased to 320.4 ± 76.1 ( P < 0.05) at sponge withdrawal, decreased 24 h later to 38.2 ± 17.9 and decreased sharply ( P < 0 05) to 1.2 ± 0.4 at the day of estrus. The controls recorded 10.9 ± 5.7 colony forming units (×10 3 ml −1) on the day of estrus which was not significantly different from the treated ewes. Qualitative features of the bacterial load (with respect to antibiotic resistance) changed with time, with increased numbers resistant to ampicillin and amoxycillin. There were no samples with resistant bacteria to cephalothin and gentamycin at any point in time. It was concluded that the use of intravaginal sponges increased bacterial flora in the vaginal mucus to the same degree despite being inserted for different periods. The different intervals of intravaginal sponge treatment did not affect the ability of the ewe to clear the bacteria reaching pre-insertion numbers by the day of estrus. Cephalothin and gentamycin seem to be the most effective antibiotic to prevent bacterial growth.

Micro-fibre pollination bags and high viability Pinus patula pollen enhance cone survival and seed set during controlled pollination

The influence of four types of isolation material and pollen viability on cone survival and seed set during controlled pollination of Pinus patula Scheide et Deppe was investigated. Very low cone-survival figures for controlled pollination of P. patula are reported by the forestry industry in South Africa. The reported studies were conducted over two pollination seasons in 1997 and 1998 and the effect of treatments was monitored during the cone development period (22 months) and was extended to a cone-analysis study after harvest. Cone-survival 20 months after pollination varied between 36% and 46% for micro-fibre isolation material compared to 19% to 32% for polythene. Developed seed yields also improved when micro-fibre material was used, with white micro-fibre (98) yielding best results compared to green micro-fibre (64), polythene (67) and sponge (56). Relative humidity (RH) inside the micro- fibre bags was up to 20% below ambient during daytime hours, while the polythene and sponge treatments maintained increased levels of relative humidity, 40-50% higher than ambient. All bag types displayed increased temperatures over ambient, with the sponge treatment reaching temperatures as much as 10 °C higher than ambient. The use of high viability pollen increased cone survival at harvest by 23% and mean number of developed seeds by 21 seeds per cone. The type of isolation material used during controlled pollination has a major impact on cone survival and seed set, while the role of pollen viability and self-pollination in successful controlled pollination was demonstrated.

THE OPTIMAL CROSSLINKING CONDITION OF COLLAGEN SPONGES AS A SCAFFOLD MATRIX FOR TISSUE ENGINEERING

Implanted collagen sponge acts as scaffold matrix as well as as carrier of growth factors. To control bioabsorbability of collagen sponge without impairing original biocompatibility, dehydrothermal crosslinking are now applied. The aim of this study was to determine the optimal condition of dehydrotheaml treatment of collagen sponge by means of evaluation of cell acceptability in vivo and in vitro. The collagen sponge was made from pepsin processed porcine atelo-collagen with freezedry-method The obtained sponges were thermally crosslinked at 140 degrees centigrade in vacuo for 1 to 48 hr. For in vivo cell infiltration test, collagen sponges were implanted subcutaneously into mice to evaluate cell acceptability of sponges as a function of crosslinking time. For in vitro initial cell attachment test, murine fibro-blasts were seeded onto the collagen sponges and cultured. After 6 hr agitation culture, DNA was extracted from the sponges with infiltrated fibroblast and then chromatically quantified. The cells lined on the implanted sponge surface and partially infiltrated into the sponge. The center portion of the implanted sponge into mice remained relatively acellular. Cell infiltration was dependent on the crosslinking times of sponges. In contrast, fibroblast was infiltrated into the center portion of sponges after 6 hr agitation culture. Among the sponges crosslinked for 1 to 48 hr, those that had received a 12 hr crosslinking treatment showed the most suitable biocompatibility for both in vivo and in vitro cell infiltration.