Response of Human Malignant Glioma Cells to Asymmetric Bipolar Electrical Impulses

Electric and electromagnetic pulses have been shown to enhance the endocytosis rate, with all-or-nothing responses beyond a field strength threshold and linear responses as a function of field strength and treatment duration utilizing bipolar symmetrical and monopolar pulses, respectively. Malignant glioma (MG) is resistant to chemotherapy. The present study looked for a new electrical impulse that can aid electrochemotherapy to deliver anticancer drugs while using less electrical energy. Bipolar asymmetric electric pulses were applied to U251MG cells suspended in physiologically conductive media in the presence of molecular probes, including Bleomycin. The delivered electric pulses with a pulse duration range of 180-500 µs and a frequency range of 100-400 Hz had a low field intensity ranging from 1.5 V/cm to 7.3 V/cm. Spectrophotometric and spectrofluorometric measurements were used to investigate the impact of these variables on cancer cell survival and the molecular probe uptake induced by the electric pulses. An all-or-nothing response was observed above a specified threshold of electric field intensity of 4 V/cm. This threshold was unaffected by changes in repetition frequency or pulse duration. It was not a temperature effect that caused the molecular probe uptake to increase. When bipolar asymmetric electric pulses were applied just before electroporation, the effectiveness of the cytotoxic impact of bleomycin was increased from 80%, when employing electroporation pulses alone, to 100%.

Complications and mortality associated with olecranon fractures in the elderly: a retrospective cohort comparison from a large level one trauma centre

BACKGROUND

Olecranon fractures in the elderly have an increasing incidence. This retrospective study aims to identify the complications and survivorship of these patients.

METHODS

All patients >70 years old treated for an olecranon fracture at our institution were identified between 2007 and 2019. Loss of reduction and/or metalwork loosening was recorded. Also noted were wound healing problems, deep/superficial infections, and any subsequent treatment including return to surgery and/or removal of metalwork.

RESULTS

From a total of 177 cases, 28 presented with concomitant fractures (16%), half of which were hip fractures. The largest treatment group underwent tension band wiring (n = 82, 46%, mean age 80.8 yrs). Twenty-one of these suffered failure of fixation (26%), all requiring return to surgery. The second largest treatment group underwent plating (n = 50 28%, mean age 80.1 yrs). Four of these suffered failure of fixation (8%), all requiring return to surgery. Forty-four patients were treated non-operatively (25%, mean age 83.8 yrs). Two patients suffered other complications (4.5%). Overall 1 year survivorship was 0.82.

DISCUSSION

Olecranon fractures in the elderly have higher than expected 1 year mortality rates. Operative management results in high complication rates, often requiring return to surgery for metalwork problems. Significant consideration of treatment options is required in this cohort.

Estimation of cancer risks during mammography procedure in Saudi Arabia

The aims of the present work were to quantify radiation doses arises from patients' exposure in mammographic X-ray imaging procedures and to estimate the radiation induced cancer risk. Sixty patients were evaluated using a calibrated digital mammography unit at King Khaled Hospital and Prince Sultan Center, Alkharj, Saudi Arabia. The average patient age (years) was 44.4 ± 10 (26–69). The average and range of exposure parameters were 29.1 ± 1.9 (24.0–33.0) and 78.4 ± 17.5 (28.0–173.0) for X-ray tube potential (kVp) and current multiplied by the exposure time (s) (mAs), respectively. The MGD (mGy) per single projection for craniocaudal (CC), Medio lateral oblique (MLO) and lateromedial (LM) was 1.02 ± 0.2 (0.4–1.8), 1.1 ± 0.3 (0.5–1.8), 1.1 ± 0.3 (0.5–1.9) per procedure, in that order. The average cancer risk per projection is 177 per million procedures. The cancer risk is significant during multiple image acquisition. The study revealed that 80% of the procedures with normal findings. However, precise justification is required especially for young patients.

Connexin-43 and aquaporin-4 are markers of ageing-related tau astrogliopathy (ARTAG)-related astroglial response

AIMS

Ageing-related tau astrogliopathy (ARTAG) appears in subependymal, subpial, perivascular, white matter (WM) and grey matter (GM) locations. Physical effects, blood-brain barrier dysfunction and blood- or vessel-related factors have been considered as aetiology. As connexin-43 (Cx43) and aquaporin-4 (AQP4) are related to these, we hypothesized that their immunoreactivity (IR) varies with ARTAG in a location-specific manner.

METHODS

We performed a morphometric immunohistochemical study measuring the densities of IR of Cx43, AQP4, AT8 (phospho-tau) and glial fibrillar acidic protein (GFAP). We analysed the amygdala and hippocampus in age-matched cases with (n = 19) and without (n = 20) ARTAG in each of the locations it aggregates.

RESULTS

We show a dramatic increase (>6-fold; P < 0.01) of Cx43 density of IR in ARTAG cases correlating strongly with AT8 density of IR, irrespective of the presence of neuronal tau pathology or reactive gliosis measured by GFAP density of IR, in the GM. In contrast, AQP4 density of IR was increased only in the WM and GM, and was associated with increased AT8 density of IR only in WM and perivascular areas.

DISCUSSION

Our study reveals distinctive astroglial responses in each of the locations associated with ARTAG. Our observations support the concept that factors related to brain-fluid interfaces and water-ion imbalances most likely play a role in the generation of ARTAG. As Cx43 is crucial for maintaining neuronal homeostasis, the ARTAG-dependent increase of Cx43 density of IR suggests that the development of ARTAG in the GM most likely indicates an early response to the degeneration of neurons.

Novel conformation-selective alpha-synuclein antibodies raised against different in vitro fibril forms show distinct patterns of Lewy pathology in Parkinson's disease

AIMS

The aim of this study was to test the hypothesis that different conformations of misfolded α-synuclein (α-syn) are present in Parkinson's disease (PD) brain.

METHODS

Using two previously characterized conformations of α-syn fibrils, we generated new conformation-selective α-syn monoclonal antibodies (mAbs). We then interrogated multiple brain regions in a well-characterized autopsy cohort of PD patients (n = 49) with these mAbs, Syn7015 and Syn9029.

RESULTS

Syn7015 detects Lewy bodies (LBs) and Lewy neurites (LNs) formed by pathological α-syn in all brain regions tested, and is particularly sensitive to LNs and small Lewy dots, inclusions believed to form early in the disease. Further, we observed colocalization between Syn7015 and an early marker of α-syn pathology formation, phospho-Ser129-α-syn, and a lack of extensive colocalization with markers of more mature pathology. In comparison, Syn9029 detects Lewy pathology in all regions examined, but indicates significantly fewer LNs than Syn7015. In addition, colocalization of Syn9029 with later markers of α-syn pathology maturation (ubiquitin and P62) suggests that the pathology detected by Syn9029 is older. Semiquantitative scoring of both LN and LB pathology in nine brain regions further established this trend, with Syn7015 LN scores consistently higher than Syn9029 LN scores.

CONCLUSIONS

Our data indicate that different conformations of α-syn pathology are present in PD brain and correspond to different stages of maturity for Lewy pathology. Regional analysis of Syn7015 and Syn9029 immunostaining also provides support for the Braak hypothesis that α-syn pathology advances through the brain.

Cognitive impairment in relation to depression, anxiety and virological response in hepatitis C patients in Egypt

OBJECTIVE

Cognitive impairment commonly occurs in hepatitis C virus (HCV) patients. The objective of this study was to estimate the prevalence and sociodemographic and clinical correlates of cognitive impairment in HCV patients before and after 12 weeks of interferon treatment in comparison with a control group.

METHODS

Hundred and sixteen consecutive HCV patients were included in the study and divided into treated and untreated groups. All patients were assessed using sociodemographic and clinical questionnaire, Montreal Cognitive Assessment Scale (MOCA) and Hospital Anxiety and Depression Scale (HADS) before and after 12 weeks of treatment or observation.

RESULTS

Thirty-eight percent of treated patients showed cognitive impairment at baseline, which increased to 69% after 12 weeks of interferon treatment. This cognitive impairment was reflected in the total MOCA score and in visuo-constructional skills, attention, concentration, working memory, language, and short-term memory, which was not shown by untreated group after 12 weeks of observation. Cognitive impairment was associated with low education, but not with depression, anxiety, or virological response.

CONCLUSIONS

Cognitive impairment is common in HCV patients and increases significantly after interferon treatment. It is not related to depression or anxiety in HCV patients. Future research should focus on prevention, treatment and outcome of cognitive impairment in HCV patients, particularly those receiving interferon therapy.

Ultrasound-guided spinal anaesthesia in obstetrics: is there an advantage over the landmark technique in patients with easily palpable spines?

BACKGROUND

Data are scarce on the advantage of ultrasound-guided spinal anaesthesia in patients with easily identifiable bony landmarks. In this study, we compared the use of ultrasound to the landmark method in patients with no anticipated technical difficulty, presenting for caesarean delivery under spinal anaesthesia.

METHODS

A total of 150 pregnant women were recruited in this randomized, controlled study. Ultrasound examination and spinal anaesthesia were performed by three anaesthetists with experience in ultrasound-guided neuraxial block. Patients were randomized to either the Ultrasound Group (n=75) or the Landmark Group (n=75). In both groups the level of L3-4 or L4-5 was identified by ultrasound (transverse and longitudinal approach) or palpation. The primary outcome was the procedure time, measured from the time of skin puncture by the introducer to the time of viewing cerebrospinal fluid at the hub of the spinal needle. Secondary outcomes were the number of skin punctures, number of passes, and incidence of successful spinal blockade.

RESULTS

The average procedure time, number of skin punctures and needle passes, were similar in both groups. The number of patients with successful spinal anaesthesia after one puncture was not statistically different between the groups.

CONCLUSION

The present results indicate that when performed by anaesthetists experienced in both ultrasound and landmark techniques, the use of ultrasound does not appear to increase the success rate of spinal anaesthesia, or reduce the procedure time or number of attempts in obstetric patients with easily palpable spines.

Ozonation as a clean technology for fresh produce industry and environment: sanitizer efficiency and wastewater quality

AIMS

Inactivating microbial contaminants in fresh produce commonly uses chlorine washing. The effectiveness of ozone was explored as an alternative to chlorine in produce washing for ensuring microbial safety while maximizing water reusability.

METHODS AND RESULTS

An ozone washing system was designed to permit continuous addition of contaminated produce and the reuse of washing water. The effectiveness of ozonation (<2 mg l(-1) ) was determined using Bacillus subtilis spores as a stricter measure of efficiency with processing time of 10 min. As a comparison, chlorine (c. 100 mg l(-1) ) was tested in parallel. Water quality characteristics, including chemical oxygen demand, total suspended solids, disinfectants concentration and microbial reduction were measured. Ozonation showed an average of 1·56 log reduction of B. subtilis spores on lettuce, while chlorination achieved a 1·30 log reduction. The effluents after ozonation demonstrated improved water quality, both in physicochemical quality and microbial quality compared to chlorination.

CONCLUSION

Aqueous ozone treatment is effective against microbial contaminants on fresh produce and enables extended use of washing water.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results provide significant data about ozone disinfection efficacy and its impact on the water reusability, which can facilitate the ozone utilization in the fresh produce production as an environmental friendly alternative.

Failures of the Dual Articular knee prosthesis due to fracture of the polyethylene post

The Dual Articular (DA) total knee replacement was designed for revision and complex primary knee arthroplasty. A number of these knees failed due to fracture of the polyethylene post. We aimed to identify the proportion of DA prostheses that failed in this manner in our hospital. The hospital database was interrogated to identify all patients undergoing revision total knee replacement under the care of one surgeon from 1995 to 2007. Case notes were then reviewed to collect information about the history surrounding the knee surgery, and determine the patient's weight at the time of surgery. Telephone follow-up was carried out to obtain complete contemporary data. Forty-eight prostheses were implanted into 39 patients (21 male, 18 female). Thirty-two of the prostheses were DA and of these, 7 underwent arthroscopy or arthrotomy to reveal a fracture of the polyethylene post (22%). T-tests showed no statistical difference in age (p=0.73) or weight (p=0.79) between the group of DA patients with fractured posts and those without. Six of the 7 fractures were in male patients (Chi-squared; p=0.01). Patients complained of pain, clicking and instability at a mean of 7 years post-surgery. Sixteen DA2000 prostheses were implanted, but none of these had failed due to a fractured polyethylene post. A high proportion of DA prostheses failed due to post fracture. We recommend that patients with DA prostheses be kept under review to detect failures early. Pain, clicking and instability should be investigated with arthroscopy and the tibial insert exchanged as appropriate.

The effect of androgen deprivation therapy on CD4/CD8 T cells in HIV-negative patients receiving definitive 3D radiation treatment for their prostate carcinoma: Final report of a prospective study

11056

Background: CD4 and CD8 T cells play critical roles in human immunity. The aim of this prospective study is to explore the correlation of the absolute CD4/CD8 T cell counts and total testosterone in patients receiving androgen deprivation therapy (ADT) with goserelin acetate and definitive radiation treatment (RT) for their prostate cancer. Methods: Thirty-four HIV-negative patients were included in this study between June 2006 and January 2007. All patients had a baseline total testosterone level (T), PSA, CD4 and CD8 T cell counts. CD4/8 T cells count was measured using flow cytometry. All patients received 6 months of ADT prior to (baseline) and during RT to the prostate. Subsequent blood samples were taken at 2, 8, 12 and 24 months. Blood samples were taken between 8–10 am to control for diurnal variations in CD4/CD8 T cell counts and T levels. To study the correlation of T with CD4/8 T cell changes, the Spearman correlation coefficient was calculated. The study was approved by the appropriate Ethics Committee. Results: Median age for the study patients was 68 years. At baseline, median testosterone level was 350 ng/dL, median CD4 T cell count was 1055 mm3, and median CD8 T cell count was 644 mm3. None of the patients received anti-androgens. At two months, testosterone was at the castrate and subnormal levels in 85% and 100% of the patients, respectively. The lower testosterone levels resulted in significant reduction of CD4 and CD8 T cell counts at 2, 8, 12 and 24 months compared to baseline counts. This effect was more pronounced for CD4 T cells at all time points (p=<0.02). At 24 months, when total testosterone levels were increasing, CD4 and CD8 T cell counts were also following these upward trends. The seen correlation between lower testosterone and decline in CD4 and CD8 T cells was only statistically significant in older patients (>65 years) and was not associated with significant decline in total white blood cell counts. Conclusions: CD4/CD8 T cell counts are sensitive to changes in total testosterone levels. Lower testosterone levels negatively affecting CD4/CD8 T cells counts at all study time points. Since CD4/CD8 T cells play major roles in cellular immunity, further studies are warranted

No significant financial relationships to disclose.

Evaluation of a Photographic Chondropathy Score (PCS) for pathological samples in a study of inflammation in tibiofemoral osteoarthritis

OBJECTIVE

Severity of structural change in knee osteoarthritis (OA) can be measured radiologically, macroscopically or microscopically. Existing methods have limitations for use in laboratory studies. We have developed a Photographic Chondropathy Score (PCS) for use with pathological samples. We have compared the ability of the different severity measures to distinguish between samples obtained at total knee replacement surgery or postmortem (PM), and to detect associations between structural severity and synovitis.

METHOD

Tibial plateaux and femoral condyles were collected from 84 patients undergoing surgery or PM. Each sample was photographed and scored. Limits of agreement and repeatability coefficients were calculated for PCS. Scores for radiological joint space narrowing (JSN) and osteophytes, histological cartilage changes (Mankin), and synovitis were assigned. Data were analysed using Mann-Whitney U tests, Spearman's correlation coefficient or logistic regression.

RESULTS

A total of 116 knees were analysed from 84 patients. Both medial tibial plateaux and total joint PCS showed good repeatability, internal consistency and reliability between observers. PCS, radiographic and Mankin's scores were all modestly positively correlated (r values 0.28-0.55). PCS and Mankin scores were greater in surgical than PM samples. Synovial inflammation was associated with higher PCS and radiological JSN scores (r values 0.43-0.48), irrespective of diagnosis.

CONCLUSION

Macroscopic, microscopic and radiographical severity scores are complementary measures of structural severity in knee OA. Synovial inflammation was associated with increased OA structural severity, suggesting a possible role of chronic synovitis in cartilage damage.

An overview of transmissible spongiform encephalopathies

Transmissible spongiform encephalopathies (TSEs) are fatal neurodegenerative disorders of humans and animals associated with an accumulation of abnormal isoforms of prion protein (PrP) in nerve cells. The pathogenesis of TSEs involves conformational conversions of normal cellular PrP (PrPc) to abnormal isoforms of PrP (PrPSc). While the protein-only hypothesis has been widely accepted as a causal mechanism of prion diseases, evidence from more recent research suggests a possible involvement of other cellular component(s) or as yet undefined infectious agent(s) in PrP pathogenesis. Although the underlying mechanisms of PrP strain variation and the determinants of interspecies transmissibility have not been fully elucidated, biochemical and molecular findings indicate that bovine spongiform encephalopathy in cattle and new-variant Creutzfeldt–Jakob disease in humans are caused by indistinguishable etiological agent(s). Cumulative evidence suggests that there may be risks of humans acquiring TSEs via a variety of exposures to infected material. The development of highly precise ligands is warranted to detect and differentiate strains, allelic variants and infectious isoforms of these PrPs. This article describes the general features of TSEs and PrP, the current understanding of their pathogenesis, recent advances in prion disease diagnostics, and PrP inactivation.

Stroke register: experience from the eastern province of Saudi Arabia

A stroke registry was established in the Eastern Province of Saudi Arabia with an estimated population of 750,000 inhabitants of whom 545,000 are Saudi citizens. The register started in July 1989 and ended in July 1993. The Gulf war led to its interruption from August 1990 to August 1991. Four hundred eighty-eight cases (314 males, 174 females) of first-ever strokes affecting Saudi nationals were registered over the 3-year period. The crude incidence rate for first-ever strokes was 29.8/100,000/year (95% CI: 25.2-34.3/100,000 year). When standardized to the 1976 US population, it rose up to 125.8/100,000/year. Ischemic strokes (69%) predominated as in other studies but subarachnoid hemorrhage (SAH) was extremely rare (1.4%). The important risk factors were: systemic hypertension (38%), diabetes mellitus (37%), heart disease (27%), smoking (19%) and family history of stroke (14%). Previous transient ischemic attacks (3%) and carotid bruits (1%) were uncommon. The 30-day case fatality rate was 15%. The study showed that the age-adjusted stroke incidence rate for Saudis in this region is lower than the rates reported in developed countries but within the range reported worldwide. The pattern of stroke in Saudi Arabia is not different from that reported in other communities with the exception of the low incidence of SAH. The risk factors are similar to findings in other studies except for the high frequency of diabetes mellitus in our cases. The lower mortality rate was probably due to the younger age of the population and the availability of free medical services for management of cases.

Batch-by-batch analysis of topographic changes induced by sutured and sutureless clear corneal incisions

PURPOSE

To evaluate the effect of a suture on surgically induced corneal topographic changes in 5.0 mm clear corneal incisions.

SETTING

University Eye Hospital, Vienna, Austria.

METHODS

Thirty-seven eyes that had cataract surgery were included in the prospective study. A 5.0 mm long and 0.3 mm deep precut was followed by preparation of a corneal tunnel. After phacoemulsification and intraocular lens implantation, the self-sealing wound was left unsutured in 19 eyes; one radial 11-0 nylon suture was applied in 18 eyes. Using a TMS-1 videokeratoscope, corneal topography was measured preoperatively and at 1 week and 1 and 3 months postoperatively. The topographic data were evaluated by statistical batch-by-batch analysis. Each topographic image was cut into 178 fields in eight concentric rings. The refractive values of these fields were stored in a database. Differences between the four readings of each patient were calculated and the mean differences of the 178 fields in each group were transformed into color-coded maps. The significance of topographical changes and group comparisons of induced changes were computed by Wilcoxon tests.

RESULTS

Both groups exhibited significant temporal flattening and vertical steepening. The unsutured eyes also displayed significant nasal flattening. Sutureless 5.0 mm clear corneal incisions induced significantly more vertical steepening and nasal flattening than sutured incisions.

CONCLUSION

Application of one radial 11-0 nylon suture in 5.0 mm temporal clear corneal incisions significantly reduced shape changes in the nasal corneal region.

Fate-map analysis of the epiblast of the dasyurid marsupial Sminthopsis macroura (Gould)

Allocation of cells in the marsupial epiblast to embryonic and extra-embryonic domains has to date been studied only histologically. An unresolved issue in marsupial embryology has been the existence of a medullary plate. We re-examined the hypotheses that the medullary plate, or neurectoderm, arises before notochord formation and that the integumentary ectoderm is segregated from the ectoderm after the formation of the medullary plate. By marking epiblast cells in 65 Day-8 embryos of the dasyurid marsupial Sminthopsis macroura, with the lipophilic cell-surface marker, DiI, we demonstrated that the so-called medullary plate contains progenitors of the integumentary ectoderm of the neck, chest, limbs and flank of the embryo. Thus, cell-allocation processes in the epiblast must have segregated the entire complement of embryonic ectoderm in one event, not separate events. It is concluded that the embryonic structure called 'medullary plate' in marsupial embryos is misnamed since, in fact, it consists of both integumentary ectoderm and neurectoderm.

The type and differentiation of cells in vitro from unilaminar and bilaminar blastocysts of two marsupials, Antechinus stuartii and Sminthopsis macroura

The type and ability to differentiate in vitro of cells found in blastocysts of two marsupials were examined. Thirteen unilaminar blastocysts on Day 7 to Day 12 of gestation and 24 bilaminar blastocysts on Day 16 and Day 18 of gestation were collected from 11 brown antechinus, Antechinus stuartii. A total of of 77 unilaminar blastocysts on Day 5 and Day 6 of gestation and a total of 61 bilaminar blastocysts on Day 6 and Day 7 of gestation were collected from 40 stripe-faced dunnarts, Sminthopsis macroura. Pluriblast and trophoblast cells, confined to separate hemispheres, were found in unilaminar and bilaminar blastocysts, establishing that the blastocyst epithelium was not a protoderm. Hypoblast cells were found only in bilaminar blastocysts. Pluriblast and hypoblast cells did not differentiate or proliferate in up to eight weeks in culture. A small number of trophoblast cells transformed to a multinucleate state but the remainder did not proliferate or differentiate further. The presence of murine leukaemia inhibitory factor or medium conditioned by exposure to marsupial fibroblast feeder layer was not required for the maintenance of an undifferentiated state. Differentiation, proliferation and attachment of cells were not influenced by the presence of the yolk mass or the egg coats in culture. The time taken for attachment of dissociated cells varied significantly between cultures with no substrate and with collagen, fibronectin or laminin (P = 0.001, ANOVA) but did not vary significantly between substrates. The substrates did not influence the state of differentiation of the cells.

The clinicopathological features of bladder carcinoma among Saudis in Riyadh Central Hospital

In a retrospective study, the records of 54 Saudi patients constituting 35.2% of the total number of patients with bladder carcinoma presenting to Riyadh Central Hospital over a seven year period (1985G to 1992G) were reviewed. Eighty-one percent of the patients were habitants of the Central Province of Saudi Arabia. Their mean age was 60 +/- 14.8 years. Male to female ratio was 5:1; gross hematuria was the main presenting symptom, occurring in 90% of patients. Twenty-four patients presented six months or more after the onset of symptoms. Upper tract deterioration was noted in 50% of cases at the time of initial presentation. A total of 76.9% of bladder tumors were transitional cell carcinoma, 19.2% were squamous cell carcinoma and 3.8% were poorly differentiated. Only 29% were superficial tumors while 71% were at least muscle-invading at presentation. The majority of tumors were of high grade. This study shows that high grade muscle-invading transitional cell carcinoma is the most frequent histological pattern of bladder tumor in Riyadh Central Hospital. Delay in patient presentation associated with a tendency for invasion of bladder tumor in this region resulted in a high percentage of incurable disease.

Embryonic development in culture of the marsupials Antechinus stuartii (Macleay) and Sminthopsis macroura (Spencer) during preimplantation stages

Forty-nine blastocysts from 11 brown antechinus, Antechinus stuartii, and 96 blastocysts from 17 stripe-faced dunnarts, Sminthopsis macroura, were used to develop a culture system for embryos during preimplantation stages. Blastocysts of brown antechinus were collected on Days 6-9 for unilaminar stages, Days 16-21 for bilaminar stages and Days 20 and 21 for trilaminar stages. Blastocysts of stripe-faced dunnarts were collected on Day 6 for unilaminar stages, Days 6-8 for bilaminar stages and Day 8 for trilaminar stages. Culture media were Dulbecco's modified Eagle's medium (DMEM) with 4.5% glucose and Whittingham's T6 medium both of which were supplemented with 5, 10, 12.5 and 20% fetal calf serum (FCS). Antechinus serum (5%) and bovine serum albumin (0.1%, 0.2%) were also added to some media. Human amniotic fluid (HAF) and Monomed media were also tested. Blastocysts were cultured at 35 degrees C in 5% CO2 in air. DMEM + 10% FCS and HAF supported normal development for the longest periods and over the greatest range of stages. Developmental failure of blastocysts in vitro during expansion of the unilaminar blastocyst and formation of the bilaminar blastocyst suggests that these stages may be dependent on uterine signals. When cultured in DMEM + 10% FCS, the rate of development of bilaminar and trilaminar blastocysts into organogenesis was 4 h slower than in vivo in the stripe-faced dunnart and about 6 h slower than in vivo in the brown antechinus. Embryos of stripe-faced dunnarts were cultured to within 18 h of birth.

Common features and surgical interference in a prevalent oral cancer in Saudi Arabia (a preliminary report)

Oral carcinoma is the third most common malignant neoplasm in the Western region of Saudi Arabia. Its specific pathological features and possible aetiological factors contributing to its high incidence are discussed. The role of 'Shamma', which is a quid used by many local inhabitants, is also discussed. Our experience with the first four cases treated by surgery is presented. Recommendations are made for the early diagnosis and detection of oral carcinoma in this region.