Critical role of the long non-coding RNAs (lncRNAs) in radiotherapy (RT)-resistance of gastrointestinal (GI) cancer: Is there a way to defeat this resistance?

Radiotherapy (RT) is a frequently used treatment for cervical cancer, effectively decreasing the likelihood of the disease returning in the same area and extending the lifespan of individuals with cervical cancer. Nevertheless, the primary reason for treatment failure in cancer patients is the cancer cells' resistance to radiation therapy (RT). Long non-coding RNAs (LncRNAs) are a subset of RNA molecules that do not code for proteins and are longer than 200 nucleotides. They have a significant impact on the regulation of gastrointestinal (GI) cancers biological processes. Recent research has shown that lncRNAs have a significant impact in controlling the responsiveness of GI cancer to radiation. This review provides a concise overview of the composition and operation of lncRNAs as well as the intricate molecular process behind radiosensitivity in GI cancer. Additionally, it compiles a comprehensive list of lncRNAs that are linked to radiosensitivity in such cancers. Furthermore, it delves into the potential practical implementation of these lncRNAs in modulating radiosensitivity in GI cancer.

CARDIOPROTECTIVE EFFECT OF DICHLOROMETHANE VALERIAN (VALERIANA OFFICINALIS) EXTRACT ON ISCHEMIA-REPERFUSION-INDUCED CARDIAC INJURIES IN RATS

Background

Valepotriate is an active ingredient of valerian (Valeriana officinalis) with strong antioxidant activity that is effective for numerous cardiovascular diseases.

Objective

The aim of this study was to investigate the effect of an active ingredient of V. officinalis extract on ischemia-reperfusion-induced cardiac injuries in male rats.

Methods

Thirty-two male rats were subjected to ischemia for 40 minutes and reperfusion for five days. The rats were divided into 4 groups of 8 each; group 1 (control) was given normal saline, and groups 2-4 were gavaged with 0.2, 0.1, 0.05 mg/kg of valepotriate extract, respectively, and received extract (0.2 mg/kg ip) two weeks before ischemia induction.

Results

Dichloromethane V. officinalis (valepotriate) extract exerted a protective effect against ischemia-reperfusion-induced injuries. So that infarct size and number of ventricular arrhythmia and ventricular escape beats decreased compared to the control group. Moreover, ST segment amplitude, QTC interval, and heart rate decreased in the injured hearts and serum levels of antioxidant enzymes glutathione peroxidase, catalase, and superoxide dismutase increased. Biochemical markers malondialdehyde and lactate dehydrogenase also decreased on day 5 after the onset of reperfusion.

Conclusion

V. officinalis extract may have a protective effect against myocardial ischemia-reperfusion by producing antioxidant effects.

P-388 Isolation and characterization of human uterine fluid lavage-derived extracellular vesicles by three different methods for optimal embryo transfer timing discovery

Study question

What is the suitable method for isolating extracellular vesicles (EVs) from a small volume of Uterine Fluid Lavage (UFL)?

Summary answer

It seems that the qEV column can help in faster, precise, and gentle isolation of EVs from small amounts of UFL.

What is known already

Several studies have discovered that existing EVs in the UFL, which are informative carriers, reflect cytological and molecular conditions of the uterine environment. The relative amounts of the EV components are different in various physiological situations. So, they are the ideal source for precise molecular analysis of the uterine condition to identify the Window of Implantation (WOI) for appropriate embryo transfer (ET) timing. There is limited information describing the most efficient method for EV isolation from a low-volume sample of biological fluids. In particular, EV separation from some biological fluids such as UFL is more complicated because of the viscosity.

Study design, size, duration

The study was conducted in two steps; first, the pre-implantation UFL sampling effect was studied on the implantation and clinical pregnancy rates. UFLs were obtained from 20 IVF Frozen Embryo Transfer (FET) patients as the case group. The control group consisted of 20 FET patients without lavage. In the second step, UFLs (n = 30) were collected and pooled. The EVs were extracted by ultracentrifugation (UC), Sucrose cushion (Suc), and Size-exclusion chromatography (by the qEV column) methods.

Participants/materials, setting, methods

First, UFL was collected two days before frozen blastocyst ET from the case group using an intrauterine insemination catheter attached to a syringe. Then, patients were compared with control at the seventh week. Second, EVs were extracted from pooled UFL samples and characterized by Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM), and Western Blot (WB). Albumin contamination was detected by SDS-PAGE. Total RNA was extracted, and Real-time PCR was performed for six housekeeping genes.

Main results and the role of chance

A comparison between case and control groups indicated no significant difference for implantation and clinical pregnancy rates. Moreover, we have confirmed the presence of EVs in UFL that were successfully isolated, by the UC, Suc, the qEV methods. The SEM images showed that the collected vesicles were morphologically spherical. The DLS analysis revealed that the intensity peak of isolated particles with the UC and Suc methods were 281 nm and 216 nm, respectively. Extracted EVs using the qEV technique were smaller and homogenized in size, with an intensity peak of 67.7 nm. SDS-PAGE of EVs showed a weaker albumin band in the qEV column (with a 100 kDa filter) method than the UC, Suc, and qEV column (with a 30 kDa filter) methods. Although, their quantification showed no significant differences. WB analysis indicated common EV markers (D81, CD9, CD63, and TSG101) showed better expression using the qEV extraction technique. But CD9 and TSG101 had lower expression levels in EVs isolated using Suc and UC, respectively. Calnexin was not detected in the isolated EVs. The GAPDH, 18SrRNA, ACTIN, GUSB, HMBS, and YWHAZ genes were detected by real-time PCR in all three EV extraction methods. The 18SrRNA gene showed better CT values.

Limitations, reasons for caution

Uterine fluid samples collection from qualified study groups and the patient’s follow-up for ensuring successful implantation and clinical pregnancy are time-consuming. The low volume of uterine fluid lavage sample and consequently the low number of extracellular vesicles inside it was also the limitation of this study.

Wider implications of the findings

Endometrial receptivity assay is difficult to study non-invasively. Herein, endometrial secretome EVs as a minimally invasive source for uterine environment molecular assessment is presented. High-throughput analysis of EV components can offer biomarkers for individual determination of ET timing, providing an additional method to use with transvaginal-ultrasonography for assessing endometrial receptivity.

Trial registration number

not applicable

Investigation of the Effect of PEG Detoxification on Diphtheria Vaccine

Immunization has been considered a successful global health program that saves many persons' lives each year. The vaccines reduce the risk of getting the disease by building immunity in the body. Therefore, the constant availability of essential vaccines is an important factor in community health. One of the most important vaccines is the diphtheria vaccine, which is usually used as Multivalent diphtheria-tetanus-pertussis (DTP) combination vaccines. The production of this vaccine takes about 45 days, from the initial bacterial culture to the end of toxin production. However, the production of this vaccine can be optimized in case the production stages are carried out under normal conditions. In this study, a significant amount of impurities was removed after washing with phosphate buffer saline, and the toxin was then purified by Sephadex G-50. In this method, the toxin was concentrated to be stored in a smaller space (this removes the concerns for the provision of a suitable space). Another problem with the diphtheria vaccine is that it is reversible after detoxification of the toxin using formaldehyde. For this reason, it is suggested to use MPEG for detoxification, which will produce more stable covalent bonds between PEG and the first type of amine groups in the toxin chain. Tests were performed to evaluate factors, such as in vivo cytotoxicity, lack of edemas formation, the neutralizing activity of serum from guinea pigs immunized with the diphtheria toxoid inactivated with MPEG, and the immunogenic activity of the purified and modified toxin. Comparison of this PEG detoxification toxoid with the standard toxoid produced in Razi Vaccine and Serum Institution, Karaj, Iran, showed that washing with PBS and purification with Sephadex G-50 was an efficient method. The stability and reversibility of the toxoid approved by MPEG were acceptable. Therefore, the results of animal tests showed that the obtained product was stable and caused no wound or necrosis in the tested animals.

The synergy between miR-486-5p and tamoxifen causes profound cell death of tamoxifen-resistant breast cancer cells

Breast cancer (BC) is the most common type of malignancy in women. A subset of breast cancers show resistance to endocrine-based therapies. The estrogen receptor (ER) plays a critical role in developing hormone-dependent BC. Loss of ER contributes to resistance to tamoxifen therapy and may contribute to mortality. Thus, it is crucial to overcome this problem. Here, using luciferase reporter assays, qRT-PCR, and Western blot analyses, we demonstrate that the microRNA miR-486-5p targets HMGA1 mRNA, decreasing its mRNA and protein levels in ER-positive (ER+) BC cells. Consistently, miR-486-5p is significantly downregulated, whereas HMGA1 is considerably upregulated in ER+ BC samples. Remarkably, while both miR-486-5p and tamoxifen individually cause G2/M cell cycle arrest, combination treatment synergistically causes profound cell death, specifically in tamoxifen-resistant ER+ cells but not in tamoxifen-sensitive ER+ cells. Combined treatment with miR-486-5p and tamoxifen also additively reduces cell migration, invasion, colony formation, mammary spheroid formation and a CD24^-CD44⁺ cell population, representing decreased cancer stemness. However, these phenomena are independent of the tamoxifen responsiveness of the ER+ BC cells. Thus, miR-486-5p and tamoxifen exhibit additive and synergistic tumor-suppressive effects, most importantly causing profound cell death specifically in tamoxifen-resistant BC cells. Therefore, our work suggests that combining miR-486-5p replacement therapy with tamoxifen treatment is a promising strategy to treat endocrine therapy-resistant BC.

Proteome Analysis of Toxic Fractions of Iranian Cobra (Naja naja Oxiana) Snake Venom Using Two-Dimensional Electrophoresis and Mass Spectrometry

Snake venoms are mostly composed of various proteins and peptides with toxicity and pharmacological effects depending on their geographical sources. Naja naja oxiana is one of the most medically important venomous snakes in Iran and Central Asia. The bite of this type of snake can cause severe pain and swelling, as well as neurotoxicity. Without medical treatment, symptoms quickly worsen and death can occur soon. A detailed understanding of venom components can provide new insight into the production of antivenom against toxic agents instead of crude venom. Specific antibodies against toxic fractions are of utmost importance in neutralizing crude venom. Therefore, the proteome profile of these fractions of Naja naja oxidana venom was analyzed using fractionation by gel filtration, two-dimensional electrophoresis, mass spectrometry, and data mining. Base on the results, in total, 32 spots were detected and categorized into three protein families, namely three-finger toxin (3FTx), phospholipase, and Cysteine-rich secretory proteins (CRISP). These proteins consist of more than 70% crude venom all with a molecular weight below 25 kDa. The 3FTx as a highly diverse constituent in the venom of Naja species was in large quantity in this district. Short-chain neurotoxins, including short neurotoxin, cytotoxin, and muscarinic toxin-like protein, were in abundance, respectively. In conclusion, the recognition of toxic fractions of Naja naja oxiana in this region could be of great help in the production of an effective antivenom against similar compositions. It can also help the medical care department to find out the clinical sign of cobra venom. To the best of our knowledge, this was the first study to report the proteomic of toxic fractions of Naja naja oxiana in Iran.

Using Apelin and exercise to protect the cardiac cells: synergic effect in ischemia reperfusion injuries treatment in rats

AIM

Apelin is an active endogenous peptide, which affects blood vessels. Also exercise increases angiogenesis after myocardial infarction and exerts cardio protective effects. The aim of the present study was to investigate the effect of Apelin and aerobic exercise on reducing the severity of Ischemia-reperfusion injury in rats.

METHODS

The rats were divided into the following 4 groups 8 weeks before surgery (Langendorff model of perfusion): I) Ischemia-reperfusion (I/R), II: Exercise Ischemia- reperfusion (EX+I/R), III: Apelin+Ischemia-reperfusion (APE+I/R) (Apelin 10 nmol/kg/day, i.p), and IV: Exercise+Apelin+Ischemia-reperfusion (EX+APE+I/R). Exercise was performed on a treadmill 8 weeks before the surgery at a speed of 17 m/min for 10 to 50 min/day. The ventricular function was evaluated after I/R injury, histopathological and immunohistopathology indices were then measured at the scar tissue.

RESULTS

The results of H(et)E, Masson's trichrome staining indicated that APE+EX pre-treatment reduced cardiac fibrosis and the percentage of collagen deposition. It also enhanced the microvessels density (MVD) and decreased the number of inflammatory cells and apoptosis rate.

CONCLUSION

According to our study, Apelin and exercise preconditioning had anti-fibrotic and anti-apoptotic effects on the ischemia-reperfusion myocardium cells, which could lead to the protection of cardiac cells (Tab. 5, Fig. 3, Ref. 33).

Using Apelin and exercise to protect the cardiac cells: synergic effect in ischemia reperfusion injuries treatment in rats

AIM

Apelin is an active endogenous peptide, which affects blood vessels. Also exercise increases angiogenesis after myocardial infarction and exerts cardio protective effects. The aim of the present study was to investigate the effect of Apelin and aerobic exercise on reducing the severity of Ischemia-reperfusion injury in rats.

METHODS

The rats were divided into the following 4 groups 8 weeks before surgery (Langendorff model of perfusion): I) Ischemia-reperfusion (I/R), II: Exercise Ischemia- reperfusion (EX+I/R), III: Apelin+Ischemia-reperfusion (APE+I/R) (Apelin 10 nmol/kg/day, i.p), and IV: Exercise+Apelin+Ischemia-reperfusion (EX+APE+I/R). Exercise was performed on a treadmill 8 weeks before the surgery at a speed of 17 m/min for 10 to 50 min/day. The ventricular function was evaluated after I/R injury, histopathological and immunohistopathology indices were then measured at the scar tissue.

RESULTS

The results of H(et)E, Masson's trichrome staining indicated that APE+EX pre-treatment reduced cardiac fibrosis and the percentage of collagen deposition. It also enhanced the microvessels density (MVD) and decreased the number of inflammatory cells and apoptosis rate.

CONCLUSION

According to our study, Apelin and exercise preconditioning had anti-fibrotic and anti-apoptotic effects on the ischemia-reperfusion myocardium cells, which could lead to the protection of cardiac cells (Tab. 5, Fig. 3, Ref. 33).

Effect of sequential therapy on treatment of Helicobacter pylori infection in children

BACKGROUND

Helicobacter pylori infection which plays a major role in the etiology of chronic gastritis and duodenal ulcers in children and adults is one of the commonest chronic infection worldwide. Cure of the infection leads to healing of gastric inflammation and prevention of peptic ulcer.

OBJECTIVE

The aim of this study was to evaluate the efficacy of the sequential therapy for treatment of Helicobacter pylori infection.

MATERIALS AND METHODS

In this study, 40 children with symptoms of H. Pylori that the infection was proved by endoscopy and biopsy and rapid urease test (UBT) were enrolled, and received sequential therapy (Lansoprazol, Amoxicillin) for 5 days and (Lansoprazol, Metronidazole and Clarithromycin) for next 5 days. The eradication rate of therapy was evaluated by stool antigen test 6 weeks after completion of therapy. This study was carried out in Pediatric Gastroenterology Clinic of Shiraz University of Medical Sciences, Shiraz, Iran. This study was approved by ethic committee of Shiraz University of Medical Sciences.

RESULTS

Forty children with mean age of (10.8±4 years) were evaluated. The most common symptom on first admission was epigastric pain (82.5%), with mean duration of symptoms (16±14.5 month). The most common endoscopic findings was redness and erosion of the antrum (55%) and the most pathologic findings was chronic gastritis (77.5%). The most drug adverse effect was nausea (22.5%). The eradication rate of sequential therapy was 82.5%.

CONCLUSION

Eradication rate of sequential therapy was 82.5% among our cases.

A genetic programming predictive model for parametric study of factors affecting strength of geopolymers

Genetic programming to present a predictive model for parametric analysis of the factors affecting compressive strength of geopolymers.

An inset CT specimen for evaluating fracture in small samples of material

In evaluations on the fracture behavior of hard tissues and many biomaterials, the volume of material available to study is not always sufficient to apply a standard method of practice. In the present study an inset Compact Tension (inset CT) specimen is described, which uses a small cube of material (approximately 2×2×2mm(3)) that is molded within a secondary material to form the compact tension geometry. A generalized equation describing the Mode I stress intensity was developed for the specimen using the solutions from a finite element model that was defined over permissible crack lengths, variations in specimen geometry, and a range in elastic properties of the inset and mold materials. A validation of the generalized equation was performed using estimates for the fracture toughness of a commercial dental composite via the "inset CT" specimen and the standard geometry defined by ASTM E399 (2006). Results showed that the average fracture toughness obtained from the new specimen (1.23±0.02MPam(0.5)) was within 2% of that from the standard. Applications of the inset CT specimen are presented for experimental evaluations on the crack growth resistance of dental enamel and root dentin, including their fracture resistance curves. Potential errors in adopting this specimen are then discussed, including the effects of debonding between the inset and molding material on the estimated stress intensity distribution. Results of the investigation show that the inset CT specimen offers a viable approach for studying the fracture behavior of small volumes of structural materials.

Aging and the reduction in fracture toughness of human dentin

An evaluation of the crack growth resistance of human coronal dentin was performed on tissue obtained from patients between ages 18 and 83. Stable crack extension was achieved over clinically relevant lengths (0< or = a < or =1mm) under Mode I quasi-static loading and perpendicular to the nominal tubule direction. Results distinguished that human dentin exhibits an increase in crack growth resistance with extension (i.e. rising R-curve) and that there is a significant reduction in both the initiation (K(o)) and plateau (K(p)) components of toughness with patient age. In the young dentin (18< or =age< or =35) there was a 25% increase in the crack growth resistance from the onset of extension (K(o)=1.34 MPa m(0.5)) to the maximum or "plateau" toughness (K(p)=1.65 MPa m(0.5)). In comparison, the crack growth resistance of the old dentin (55< or =age) increased with extension by less than 10% from K(o)=1.08 MPa m(0.5) to K(p)=1.17 MPa m(0.5). In young dentin toughening was achieved by a combination of inelastic deformation of the mineralized collagen matrix and microcracking of the peritubular cuffs. These mechanisms facilitated further toughening via the development of unbroken ligaments of tissue and posterior crack-bridging. Microstructural changes with aging decreased the capacity for near-tip inelastic deformation and microcracking of the tubules, which in turn suppressed the formation of unbroken ligaments and the degree of extrinsic toughening.

Effect of the degree of fragmentation on embryo survival after freeze-thawing

PURPOSE

To determine if the degree of fragmentation of embryos prior to freezing correlate in a negative manner with survival after thawing.

METHODS

A retrospective review of frozen embryos thawed for purposes of embryo transfer was done. Survival and transferability rates were determined according to degree of fragmentation.

RESULTS

The chance that an embryo with < 25% fragmentation was deemed good enough for transfer upon thawing was 63.6% compared to 52.8% for embryos > 25% (p < .05).

CONCLUSIONS

Though more fragmented embryos have a lower survival rate after freeze thawing, about 50% of embryos with > 25% fragmentation will still survive the thaw and be able to be transferred.

Ectopic pregnancy is not more likely following fresh vs frozen embryo transfer

PURPOSE

To determine if the risk of ectopic pregnancy is greater following frozen vs fresh embryo transfer (ET).

METHODS

Retrospective review of pregnancy outcome from January 1, 1997 to November 30, 2003. Cryopreservation was used as a simple freezing method and one-step removal of cryoprotectant. The cycles consisted mostly of graduated estradiol and progesterone supplementation.

RESULTS

The ectopic pregnancy rate in 1,445 clinical pregnancies from fresh ET was 2.6% vs 2.0% of 975 clinical pregnancies resulting from frozen ET.

CONCLUSION

In contrast to the conclusions of two previous studies, the present study evaluating twice as many clinical pregnancies than the two aforementioned studies combined failed to show any greater risk of ectopic pregnancy when transfers were performed on day 3.

Non-homogeneous hyperechogenic echo pattern three days after frozen embryo transfer is associated with lower pregnancy rates

OBJECTIVE

To evaluate the association of mid-luteal phase echo patterns and pregnancy rates (PRs) following frozen embryo transfer (ET).

METHODS

Sonographic evaluation of endometrial echo patterns was performed three days after ET in the first frozen ET cycle of women < 40 years of age who used their own oocytes as well as all donor oocyte recipients.

RESULTS

The distribution of echo patterns and clinical PRs were similar in women using their own eggs and women who used donor oocytes; therefore all data was combined. The clinical PR was 49.5% with a hyperechogenic echo pattern vs 38.8% with a non-hyperechogenic pattern, p = .007.

CONCLUSION

A larger study of frozen ET and mid-luteal echo pattern now demonstrates conclusions similar to the data from fresh ET in hyperstimulated in vitro fertilization (IVF)-ET cycles in that failure to attain a hyperechogenic echo pattern three days after ET is associated with lower pregnancy rates.

Possible mechanism(s) for relaxant effects of Foeniculum vulgare on guinea pig tracheal chains

In a previous study the relaxant (bronchodilatory) effect of Foeniculum vulgare on isolated guinea pig tracheal chains was demonstrated. To study mechanisms responsible for this effect the present study evaluated the inhibitory effect of this plant on contracted tracheal chains of guinea pig. The relaxant effects of aqueous and ethanol extracts and an essential oil from Foeniculum vulgare were compared to negative controls (saline for aqueous extract and essential oil and ethanol for ethanol extract) and a positive control (diltiazem) using isolated tracheal chains of the guinea pig precontracted by 10 microM methacholine (group 1) and 60 mM KCl (group 2, n = 7 for each group). In the group 1, experiments diltiazem, ethanol extract, and essential oil from Foeniculum vulgare showed a significant relaxant effect on methacholine induced contraction of tracheal chains compared to those of negative controls (p < 0.05 to p < 0.001). In addition the effect of the ethanol extract was significantly greater than that of diltiazem (p < 0.001). However, the aqueous extract did not show any relaxant effect in group 1. In the group 2 experiments, only diltiazem showed a significant relaxant effect on KCl induced contraction of tracheal chains (p < 0.001). The relaxant effects of ethanol extracts and essential oil obtained in the group 2 experiments were significantly lower than those in group 1 (p < 0.05 to p < 0.001). These results confirm the bronchodilatory effects of ethanol extract and essential oil from Foeniculum vulgare. However with regard to the effect of KCl on calcium channels, the results indicated that the inhibitory effect of ethanol extracts and essential oil from Foeniculum vulgare on calcium channels is not contributing to their relaxant (bronchodilatory) effects on guinea pig tracheal chains. However the results suggest a potassium channel opening effect for this plant, which may contribute on its relaxant effect on guinea pig tracheal chains.

Neither sildenafil nor vaginal estradiol improves endometrial thickness in women with thin endometria after taking oral estradiol in graduating dosages

PURPOSE

To determine if sildenafil improves endometrial thickness better than vaginal estradiol (E2) in women with a history of thin endometria.

METHODS

Women failing to attain an 8 mm endometrial thickness on either the oocyte retrieval cycle or their first frozen embryo transfer (ET) despite an oral graduated E2 regimen were treated again with graduated oral E2 and were also randomly assigned to vaginal sildenafil or vaginal E2 therapy. Endometrial thickness was compared between the groups.

RESULTS

Neither vaginal E2 nor sildenafil significantly improved endometrial thickness or blood flow in the subsequent frozen ET-cycle.

CONCLUSIONS

These data fail to corroborate previous claims that 25 mg sildenafil four times daily intravaginally can improve endometrial thickness.

The importance of number of blastomeres when embryos are transferred in the absence of controlled ovarian hyperstimulation

PURPOSE

To determine if the previous findings that transferring embryos with a higher number of blastomeres results in higher pregnancy rates following fresh but not frozen embryo transfer (ET) was related to the use of controlled ovarian hyperstimulation (COH) in the former but not in the latter.

METHODS

Retrospective review of pregnancy and implantation rates following fresh embryo transfer of donor egg recipient cycles (where no COH is used) vs frozen ETs during the same time period according to whether there was at least one embryo with eight blastomeres transferred or not.

RESULTS

Significantly higher pregnancy rates with an 8-cell ET in donor oocyte recipient cycles but not frozen ETs.

CONCLUSIONS

A less favorable uterine environment caused by the use of high dose gonadotropin is not responsible for the once again observed difference in higher pregnancy rates with higher blastomere number in fresh vs frozen ET. However, an effect of the gonadotropin releasing hormone analogue was not ruled out by this study.

Live birth after posthumous testicular sperm aspiration and intracytoplasmic sperm injection with cryopreserved sperm: case report

PURPOSE

To determine if a viable pregnancy is possible after aspiration of sperm from the testes of a man several hours after his death.

METHOD

Following cryopreservation of the aspirated sperm, in vitro fertilization (IVF)-embryo transfer (ET) with intracytoplasmic sperm injection (ICSI) was used. The sperm selected were either those with motility or plumper non-motile sperm.

RESULTS

Fertilization of oocytes and ET occurred following all five IVF-ET cycles. A clinical pregnancy was achieved in cycle 1 with non-motile sperm and a viable pregnancy resulted from cycle 5 with ICSI performed with viable sperm.

CONCLUSION

Viable pregnancies following IVF-ET and ICSI are possible even when using testicular sperm obtained posthumously.

Insecticide-treated plastic tarpaulins for control of malaria vectors in refugee camps

Spraying of canvas tents with residual pyrethroid insecticide is an established method of malaria vector control in tented refugee camps. In recent years, plastic sheeting (polythene tarpaulins) has replaced canvas as the utilitarian shelter material for displaced populations in complex emergencies. Advances in technology enable polythene sheeting to be impregnated with pyrethroid during manufacture. The efficacy of such material against mosquitoes when erected as shelters under typical refugee camp conditions is unknown. Tests were undertaken with free-flying mosquitoes on entomological study platforms in an Afghan refugee camp to compare the insecticidal efficacy of plastic tarpaulin sprayed with deltamethrin on its inner surface (target dose 30 mg/m2), tarpaulin impregnated with deltamethrin (initially > or = 30 mg/m2) during manufacture, and a tent made from the factory impregnated tarpaulin material. Preliminary tests done in the laboratory with Anopheles stephensi Liston (Diptera: Culicidae) showed that 1-min exposure to factory-impregnated tarpaulins would give 100% mortality even after outdoor weathering in a temperate climate for 12 weeks. Outdoor platform tests with the erected materials (baited with human subjects) produced mosquito mortality rates between 86-100% for sprayed or factory-impregnated tarpaulins and tents (average approximately 40 anophelines and approximately 200 culicines/per platform/night), whereas control mortality (with untreated tarpaulin) was no more than 5%. Fewer than 20% of mosquitoes blood-fed on human subjects under either insecticide-treated or non-treated shelters. The tarpaulin shelter was a poor barrier to host-seeking mosquitoes and treatment with insecticide did not reduce the proportion blood-feeding. Even so, the deployment of insecticide-impregnated tarpaulins in refugee camps, if used by the majority of refugees, has the potential to control malaria by killing high proportions of mosquitoes and so reducing the average life expectancy of vectors (greatly reducing vectorial capacity), rather than by directly protecting refugees from mosquito bites. Mass coverage with deltamethrin-sprayed or impregnated tarpaulins or tents has strong potential for preventing malaria in displaced populations affected by conflict.

Marked improvement in clinical pregnancy rates following in vitro fertilization-embryo transfer seen when transfer technique and catheter were changed

PURPOSE

To compare in vitro fertilization (IVF) outcome with two different embryo transfer (ET) catheters: the Frydman and Wallace catheters.

METHODS

Retrospective review of outcome of IVF cycles where there was at least one embryo that had assisted hatching prior to transfer at 72 hours according to which catheter was used.

RESULTS

Pregnancy rate 17.6% per transfer with Frydman (FET-SET) vs 44.2% for fresh ETs and 15.4% and 43.2% for frozen ETs. The implantation rates for fresh ETs were 7.6% vs 20.0% for fresh and 5.7 vs 21.1% for frozen ETs.

CONCLUSION

The soft Wallace catheter is superior to the stiffer Frydman catheter when transferring embryos subjected to assisted embryo hatching.

Cumulative pregnancy rates after four embryo transfers of either fresh or frozen embryos

PURPOSE

To evaluate in the modern era of in vitro fertilization (IVF) cumulative probability of pregnancy for the first four embryo transfers (ET) irrespective of whether the embryos were fresh or frozen.

METHODS

Retrospective review over a 2 1/2 year period. Cumulative probability of pregnancy for four consecutive cycles of either fresh or frozen ETs divided into four age groups.

RESULTS

The cumulative clinical and viable pregnancy rates after four ETs were 92% and 88%; 87% and 82%; 83% and 69%; and 68% and 52% for age groups <30, 30-34, 35-39, and 40-44. The cumulative rates decline with age.

CONCLUSIONS

Pregnancy rates per transfer for the first four ETs regardless of age are similar even in IVF centers that emphasize frozen ETs.

Pregnancy rates (prs) according to embryo cell number at time of embryo transfer (ET)

PURPOSE

To evaluate pregnancy and implantation rates following fresh and frozen embryo transfer (ET) according to blastomere number.

METHODS

A retrospective study from 1/1/97 to 9/30/98 including all cycles with ETs irrespective of age.

RESULTS

65% of fresh transfers had at least one 8-cell embryo vs only 39.6% for frozen ET. The clinical pregnancy and implantation rates were higher when one 8-cell embryo was transferred (64% and 24%) vs a 5-7 cell embryo (41% and 14.5%) for fresh transfers. There was less of a difference with frozen ETs (46% and 19% for 8-cell vs 38% and 17% for 5-7 cell).

CONCLUSIONS

Since mostly only 8-cell embryos at day 3 reach the blastocyst stage, these data raise questions as to whether the quest to attain the highest pregnancy rate per transfer through blastocyst transfer, may be at the expense of overall pregnancy rate (fresh and frozen) from a given oocyte harvest.

Fresh embryo transfer is more effective than frozen for donor oocyte recipients but not for donors

BACKGROUND

Recipients of donor oocytes need to be synchronized to the donor's cycle if fresh embryos are to be transferred on the cycle of oocyte retrieval. It would be much easier to merely retrieve the oocytes from the donor, fertilize the oocytes with the recipient's male partner's spermatozoa, cryopreserve the embryos, then transfer on an oestrogen/progesterone treatment programme.

METHODS

The IVF outcomes of all patients enrolled in a shared oocyte programme from January 1997 to June 1999 were reviewed. Pregnancy and implantation rates were computed and statistically analysed.

RESULTS

There was a significantly higher clinical pregnancy rate for recipients who had a fresh embryo transfer compared with recipients whose first embryo transfer consisted of frozen/thawed embryos (63.4 versus 43.6%).

CONCLUSIONS

Conception is more likely after fresh than frozen embryo transfer with recipients but is similar to donor conception rates. If a uterine defect, per se, even without the use of the controlled ovarian stimulation regimen, could explain the difference between fresh pregnancy and implantation rates in donors versus recipients, then these same differences would have been seen when comparing frozen transfers, but they were, in fact, similar.

The presence of small uterine fibroids not distorting the endometrial cavity does not adversely affect conception outcome following embryo transfer in older recipients

PURPOSE

To determine if uterine fibroids have a negative impact in older patients having embryo transfer (ET).

METHODS

Comparison of clinical and viable pregnancy rates, implantation rates, and spontaneous abortion rates in older (>35) oocyte or embryo recipients with uterine leiomyomata compared to comparable patients without fibroids.

RESULTS

The clinical pregnancy rate per transfer was 56% in the fibroid group vs 64% for the controls. Implantation rates were also very similar (33 vs 32%7). There were no spontaneous abortion or preterm deliveries <32 weeks in the fibroid group and the average term of pregnancies was also similar.

CONCLUSION

Small fibroids not distorting the uterine cavity do not seem to negatively affect conception outcome even in older women.

Successful pregnancy following in vitro fertilization-embryo transfer despite imminent ovarian failure

There have been previously published several anecdotal cases of women in apparent or imminent ovarian failure who subsequently ovulated and became pregnant. Many of these women had been treated with estrogen. A series of cases were reported where women with hypergonadotropic hypogonadism who failed to stimulate despite gonadotropin therapy were able to ovulate when treated with pharmacologic doses of estrogen alone or in combination with human menopausal gonadotropins. Presented herein is a case of a woman with imminent ovarian failure with tubal disease who failed to stimulate with gonadotropins alone but was successful with estrogen and gonadotropins. We believe this is the first successful case of hypergonadotropic hypogonadism to conceive by in vitro fertilization.

A study to determine if certain sonographic uterine parameters are associated with multiple gestation

The objective was to determine if lower uterine artery vascular impedance is associated with a greater likelihood of multiple gestation. Color Doppler parameters of pulsatility index, resistance index, endometrial thickness and echo patterns were measured in oocyte/retrieval cycles on days of human chorionic gonadotropin injection, oocyte retrieval, and mid-luteal phase in cycles where at least 3 embryos were transferred. Comparisons of these parameters were made in patients with single versus multiple gestations. There was no association between uterine environment as measured by vascular impedance and endometrial thickness and number of embryos implanted. Thus, a more ideal uterine environment, at least as determined by these sonographic parameters, does not seem to facilitate multiple embryo implantations.

No evidence of increased uterine vascular impedance with patient ageing following IVF

A study was conducted to determine if uterine vascular impedance increases with advancing age in women undergoing ovarian stimulation for IVF. A group of 162 women who had undergone conventional IVF and embryo transfer was subdivided into three subgroups by age: 30-34 years (n = 49), 35-39 years (n = 79) and 40-44 years (n = 34). The pulsatility index (PI) and resistance index (RI) of the right and left uterine arteries were measured at baseline, on the day of oocyte retrieval, and at the mid-luteal phase. There were no differences in the average PI or RI by age at any phase of the cycle. In all age groups, the luteal phase values of PI and RI were lower than those observed earlier in the cycle. Endometrial thickness was not associated with age. There was no significant correlation between PI, RI and serum oestradiol and progesterone concentrations at any phase of the cycle. Ovarian response, as measured by average number of oocytes retrieved, decreased significantly with age. Thus, reduced pregnancy rates in older women undergoing ovarian stimulation are more likely to occur because of oocyte quality and quantity rather than uterine senescence. If future studies determine that the use of ovarian stimulation does decrease implantation rates more in older versus younger women, a mechanism other than increased uterine vascular impedance must be sought.

Hyperreactio luteinalis despite the absence of a corpus luteum and suppressed serum follicle stimulating concentrations in a triplet pregnancy

Hyperreactio luteinalis is characterized by moderate to marked cystic enlargement of the ovaries related to multiple theca lutein cysts and is associated with very high sex steroid concentrations. It is a rare condition especially in the first trimester. The case described below is believed to be the only case of hyperreactio luteinalis reported following frozen embryo transfer. This case provides an opportunity to gain further insight into the mechanism responsible for this unusual condition. The 30 year old woman demonstrated a slightly elevated LH/FSH ratio (5 and 3 mIU/ml respectively) and normal baseline androgen concentrations. Two years following oocyte retrieval she had a second frozen embryo transfer. The ovaries were normal size when the embryos were transferred and androgens were still normal. The ovaries did not begin to enlarge until 51 days from transfer. A dichorionic intrauterine pregnancy with monozygotic twins in the left gestational sac was seen. Eventually, 86 days from transfer, the ovaries enlarged to 145x103x116 mm right; and 83x95x117 mm left. Serum oestradiol was 30 078 pg/ml, beta-human chorionic gonadotrophin (HCG) 239 920 mIU/ml, serum progesterone >160 ng/ml, total testosterone 2254 ng/dl, free testosterone 42.3 pg/ml and androstenedione 7328 ng/dl. Throughout the first trimester, serum FSH was <1 mIU/ml. Thus, neither FSH nor a corpus luteum is necessary to initiate this syndrome.

Sperm extracted and cryopreserved from testes several hours after death results in pregnancy following frozen embryo transfer: case report

A 38-year-old male died suddenly on his honeymoon. Sperm was extracted from his testes 3 h following his death and cryopreserved. His wife had in vitro fertilization (IVF) and the eggs were inseminated by intracytoplasmic sperm injection (ICSI). None of the sperm were motile. Selection was based on softness and pliability. There were 4 embryos formed that cleaved, but only 2 were transferred on the retrieval cycle. The wife failed to conceive, but then had a second transfer of the 2 cryopreserved embryos. She achieved a chemical pregnancy with the beta-human chorionic gonadotropin level attaining a maximum level of 107 mIU/mL (rising from 19 mIU/mL). Though this retrieval cycle did not result in a successful pregnancy the achievement of a clinical pregnancy following frozen embryo transfer at least provides cautious optimism for other cases with similar conditions.