Compound heterozygous variants in NBAS as a cause of atypical osteogenesis imperfecta

BACKGROUND

Osteogenesis imperfecta (OI), the commonest inherited bone fragility disorder, affects 1 in 15,000 live births resulting in frequent fractures and reduced mobility, with significant impact on quality of life. Early diagnosis is important, as therapeutic advances can lead to improved clinical outcome and patient benefit.

REPORT

Whole exome sequencing in patients with OI identified, in two patients with a multi-system phenotype, compound heterozygous variants in NBAS (neuroblastoma amplified sequence). Patient 1: NBAS c.5741G>A p.(Arg1914His); c.3010C>T p.(Arg1004*) in a 10-year old boy with significant short stature, bone fragility requiring treatment with bisphosphonates, developmental delay and immunodeficiency. Patient 2: NBAS c.5741G>A p.(Arg1914His); c.2032C>T p.(Gln678*) in a 5-year old boy with similar presenting features, bone fragility, mild developmental delay, abnormal liver function tests and immunodeficiency.

DISCUSSION

Homozygous missense NBAS variants cause SOPH syndrome (short stature; optic atrophy; Pelger-Huet anomaly), the same missense variant was found in our patients on one allele and a nonsense variant in the other allele. Recent literature suggests a multi-system phenotype. In this study, patient fibroblasts have shown reduced collagen expression, compared to control cells and RNAseq studies, in bone cells show that NBAS is expressed in osteoblasts and osteocytes of rodents and primates. These findings provide proof-of-concept that NBAS mutations have mechanistic effects in bone, and that NBAS variants are a novel cause of bone fragility, which is distinguishable from 'Classical' OI.

CONCLUSIONS

Here we report on variants in NBAS, as a cause of bone fragility in humans, and expand the phenotypic spectrum associated with NBAS. We explore the mechanism underlying NBAS and the striking skeletal phenotype in our patients.

Case study of copper poisoning in a British dairy herd

Following the initial diagnosis of chronic copper poisoning (CCP), the copper (Cu) status of a British dairy herd was investigated. Eight fatal cases of CCP were identified over a 17-month period, from December 1999 to May 2001, involving seven Jersey cows and one Holstein-Friesian; seven cows were dry when CCP occurred. Case diagnostic criteria were necrotising hepatopathy associated with abnormally high liver and kidney Cu concentrations. Analysis of the ration for the high-yielding Jersey cow group revealed about 50 mg Cu/kg dry matter intake (DMI). Risk factors predisposing to fatal CCP were Jersey breed, previous high yield, first two weeks of the dry period and moderately high dietary Cu (greater than 40 mg Cu/kg DMI).

Haemoperitoneum associated with ovulation in women with bleeding disorders: the case for conservative management and the role of the contraceptive pill

Haemoperitoneum secondary to ruptured corpus luteum is a rare complication for women on anticoagulants and with certain congenital bleeding disorders. A surgical approach is often taken, leading to oophorectomy in many cases. We describe three patients presenting with haemoperitoneum in association with factor VII deficiency, factor X deficiency and sitosterolaemia. In two of the patients, recurrent episodes occurred prior to introduction of the oral contraceptive pill. Conservative management with blood product and factor concentrate support was successful in avoiding surgery in three of the five episodes of bleeding. These cases demonstrate that preservation of ovarian function is possible with a conservative approach and recurrent episodes may be prevented by suppression of ovulation.

Prevalence of faecal excretion of verocytotoxigenic Escherichia coli 0157 in cattle in England and Wales

During the decade to 1999, the incidence of human infections with the zoonotic pathogen verocytotoxin-producing Escherichia coli O157 (VTEC O157) increased in England and Wales. This paper describes the results of a survey of 75 farms to determine the prevalence of faecal excretion of VTEC O157 by cattle, its primary reservoir host, in England and Wales. Faecal samples were collected from 4663 cattle between June and December 1999. The prevalence of excretion by individual cattle was 4.2 per cent (95 per cent confidence interval [CI] 2.0 to 6.4) and 10.3 per cent (95 per cent CI 5.8 to 14.8) among animals in infected herds. The within-herd prevalence on positive farms ranged from 1.1 to 51.4 per cent. At least one positive animal was identified on 29 (38.7 per cent; 95 per cent CI 28.1 to 50.4) of the farms, including dairy, suckler and fattening herds. The prevalence of excretion was least in the calves under two months of age, peaked in the calves aged between two and six months and declined thereafter. The phage types identified most widely were 4, 34 and 2, which were each found on six of the 29 positive farms.

Kikuchi-Fujimoto disease: a rare but important cause of lymphadenopathy

Cervical lymphadenopathy is a common problem in children. Kikuchi-Fujimoto disease (histiocytic necrotizing lymphadenitis) is a rare condition that causes persistent lymphadenopathy and has a characteristic histological appearance. Kikuchi-Fujimoto disease is well recognized in Japan, where it was first described, but descriptions in the paediatric literature are sparse. Paediatricians may therefore be unaware of this rare but important condition. The case is described of a 14-y-old girl suffering from fatigue, weight loss, night sweats and lymphadenopathy. The predominance of systemic symptoms prompted an extensive investigation. The diagnosis of Kikuchi-Fujimoto disease was made after direct histological examination of a lymph node biopsy. The case illustrates the clinical features of this little-known condition and highlights the potential confusion with other diagnoses. The pathological features are discussed and the literature reviewed.

CONCLUSION

Kikuchi-Fujimoto disease should be considered in cases of persistent lymphadenopathy. An early biopsy can be instrumental in preventing unnecessary investigations and potentially harmful treatments.

Hormonal regulation of oxytocin-induced prostaglandin F(2alpha) secretion by the bovine and ovine uterus in vivo

In long-term ovariectomized ewes and cows, endometrial oxytocin receptors rest at relatively high levels but oxytocin is unable to induce prostaglandin F(2alpha) release. A series of studies were carried out to investigate the roles of physiological levels of progesterone and estradiol in "activating" these receptors in terms of permitting oxytocin-induced prostaglandin F(2alpha) release. In long-term ovariectomized cows, treatment with progesterone, but not estradiol, resulted in the induction of responsiveness to oxytocin. This responsiveness appeared within 2 d of progesterone treatment, reached a maximum by 6 d and was maintained to Day 18. In ovariectomized ewes, while estradiol treatment did induce temporary responsiveness to oxytocin after 3 d of treatment, treatment with progesterone was required to induce sustained responsiveness that appeared by Day 9 of treatment and was maintained to Day 12. Measurement of endometrial receptors for oxytocin revealed a significant decline in oxytocin receptors by Day 6 of progesterone treatment when responsiveness to oxytocin was maximal, demonstrating that receptor concentrations were not a limiting factor. The most likely mechanism by which progesterone treatment induces responsiveness to oxytocin may be through the up regulation of post receptor signaling pathways and/or enzymes involved in prostaglandin synthesis.

The marginal seal of Class II restorations: flowable composite resin compared to injectable glass ionomer

The objective of this study was to investigate the effect of a flowable composite resin (Tetric Flow) versus an injectable glass ionomer (Fuji II LC) on microleakage at the cavosurface margin of the proximal box of Class II restorations in permanent teeth in-vitro. Thirty caries and restoration-free human bicuspids were prepared with mesial and distal slot preparations and were filled either with a bonding agent (Optibond) plus a flowable composite resin (Tetric Flow), Group I; bonding agent (Optibond) plus a flowable glass ionomer (Fuji II LC), Group II; or a flowable glass ionomer (Fuji II LC) with no bonding agent, Group III. All specimens were then immersed in a 2% solution of basic fuschin dye for 24 hours to allow for dye penetration into possible existing gaps. These teeth were then carefully sectioned mesially/distally into two pieces using an Isomet saw. The teeth were then studied under a binocular microscope to measure depths of dye penetrations as an indication of marginal microleakage at the gingival cavosurface margin and scored as follows: 0 = no dye penetration, 1 = dye penetration into enamel only, 2 = dye penetration into enamel and dentin, 3 = dye penetration into the pulp. The specimens were also evaluated using a SEM. The results showed that there were statistically significant differences between Groups I (Tetric Flow) and (Fuji II LC plus bonding agent), II in favor of Group I; between Groups I and (Fuji II LC with no bonding agent), III in favor of Group I; as well as Groups II and III in favor of Group II (Fuji II LC plus bonding agent). Group I (bonding agent plus flowable composite resin) showed significantly less microleakage. Group II (bonding agent plus flowable glass ionomer) demonstrated a bond that existed between the bonding agent and the glass ionomer but microleakage within microgaps of the glass ionomer itself Group III (flowable glass ionomer plus no bonding agent) demonstrated significant microleakage between the glass ionomer and tooth structure, microgaps within the glass ionomer, and lack of retention of the restoration. It appears that the use of a flowable composite resin (Tetric Flow) plus a bonding agent (Optibond) in the proximal box of a Class II restoration in permanent teeth will significantly reduce the microleakage at the cavosurface margin when compared with an injectable glass ionomer (Fuji II LC) with or without a bonding agent (Optibond).

Laparoscopic staging of malignant disease

The earliest applications of laparoscopy were for diagnostic procedures. The goal was to make a diagnosis while sparing the patient a major, and often futile, operation. However, the view was limited and it was not possible to palpate organs or masses. The recent development of advanced laparoscopic techniques and ultrasound have improved our view and restored our "sense of touch". These innovations bring the goal of minimally invasive diagnosis and staging closer to reality. This paper reviews the current literature on the laparoscopic staging of cancer with an emphasis on patient selection, diagnostic accuracy, and the reduction in morbidity which can be achieved.

Advanced laparoscopy: "the next generation". The adrenal, kidney, spleen, pancreas, and liver

Following the rapid acceptance of laparoscopic cholecystectomy, a few adventurous surgeons "dared to boldly go where no one had gone before." They sought to achieve the same reduction in morbidity while accomplishing the same surgical goals. This paper will briefly review the current status of minimal access surgery for the solid organs of the abdomen. It will focus on the indications, risks, limitations, and on the balance between the trauma of access and the trauma of the procedure itself. As new techniques and equipment emerge and experience and data are accumulated, this balance may shift. Some of these procedures are in their infancy while others are rapidly becoming the new "Gold Standard".

Effects of arterial infusions of adrenalin and acetylcholine on luteal secretion of progesterone and oxytocin in goats

The effects of close intra-arterial infusion of acetylcholine and adrenalin on ovarian secretion of progesterone and oxytocin were examined on Day 10 of the estrous cycle in goats (estrus = Day 0). Acetylcholine (15 micrograms/min) was without effect, but adrenalin (10 micrograms/min) significantly (P < 0.001) raised both progesterone and oxytocin concentrations in ovarian vein plasma. These results show that luteal hormone secretion is enhanced in the goat by beta-adrenergic stimulation and suggest that, as in the sheep and cow, there may be neuroendocrine involvement in the regulation of caprine luteal function.

Role of early luteal phase progesterone in control of the timing of the luteolytic signal in cows

The effects of the pattern and concentration of early luteal phase progesterone on subsequent prostaglandin F2 alpha release in response to exogenous oxytocin was investigated during simulated luteal phases in ovariectomized cows treated with progesterone and oestradiol in patterns designed to simulate the range of luteal phase concentrations that occur naturally. In the first experiment, three groups of four cows received different concentrations of early luteal phase progesterone to determine the effective concentration in terms of cycle control. The results show that a plasma progesterone concentration early in the luteal phase as low as 0.6 ng ml-1 was sufficient to affect the timing of the subsequent luteolytic signal. In the second experiment, an early (day 1), a normal (day 4) or a late (day 7) postovulatory increase in progesterone was recreated in three groups of four cows. Responsiveness to oxytocin in the early progesterone group developed 3 days earlier than in the normal progesterone group, demonstrating the ability of early progesterone to advance the luteolytic signal. However, in the late progesterone group, there was no delay in the development of responsiveness to oxytocin compared with the normal progesterone group, demonstrating that the luteolytic signal is programmed to occur by a given time, irrespective of the early progesterone pattern. This demonstrates that a factor other than the timing of the early luteal phase progesterone increase ultimately must control the timing of luteolysis in cows.

Effect of adrenalin and propranolol on progesterone and oxytocin secretion in vivo during the caprine estrous cycle

The effects of jugular infusions of adrenalin and the beta-adrenergic receptor antagonist propranolol on plasma concentrations of progesterone and oxytocin were examined at 2 different stages of the caprine estrous cycle. Adrenalin (25 micrograms.kg-1h-1) significantly (P < 0.05) increased oxytocin secretion on Day 3 and Day 10 of the cycle (estrus = Day 0); progesterone concentrations were significantly (P < 0.05) elevated on Day 10 alone. Propranolol had no effect on progesterone secretion yet significantly (P < 0.05) reduced oxytocin concentrations on Day 3. These results suggest that there may be neuroendocrine involvement in the regulation of luteal oxytocin secretion in the goat.

Telementoring. A practical option in surgical training

BACKGROUND

Telemedicine offers significant advantages in bringing consulting support to distant colleagues. There is a shortage of surgeons trained in performing advanced laparoscopic operations.

AIM

Our aim was to evaluate the role of telementoring in the training of advanced laparoscopic surgical procedures.

METHODS

Student surgeons received a uniform training format to enhance their laparoscopic skills and intracorporeal suturing techniques and specific procedural training in laparoscopic colonic resections and Nissen fundoplication. Subsequently, operating rooms were equipped with three cameras. Telestrator (teleguidance device), instant replay (to critique errors), and CD-ROM programs (to provide information of reference) were used as intraoperative educational assistance tools. In phase I, four colonic resections were performed with the mentor in the operating room (group A) and four colonic resections were performed with the mentor on the hospital grounds, but not in the operating room (group B). The voice and video signals were received at the mentor's location, using coaxial cable. In phase II, two Nissen fundoplications were performed with the mentors in the operating room (group C) and two Nissen fundoplications were performed with the mentors positioned five miles away from the operating room (group D), using currently existing land lines at the T-1 level.

RESULTS

There were no differences in the performances of the surgeons and outcome of the operations between groups A & B and C & D. It was possible to tackle the intraoperative problems effectively.

CONCLUSIONS

The telementoring concept is potentially a safe and cost-effective option for advanced training in laparoscopic operations. Further investigation is necessary before routine transcontinental patient applications are attempted.

Regulation of oxytocin, oestradiol and progesterone receptor concentrations in different uterine regions by oestradiol, progesterone and oxytocin in ovariectomized ewes

The regulation of oxytocin, oestradiol and progesterone receptors in different uterine cell types was studied in ovariectomized ewes. Animals were pretreated with a progestogen sponge for 10 days followed by 2 days of high-dose oestradiol to simulate oestrus. They then received either low-dose oestradiol (Group E), low-dose oestradiol plus progesterone (Group P) or low-dose oestradiol, progesterone and oxytocin (via osmotic minipump; Group OT). Animals (three to six per time-point) were killed following ovariectomy (Group OVX), at oestrus (Group O) or following 8, 10, 12 or 14 days of E, P or OT treatment. In a final group, oxytocin was withdrawn on day 12 and ewes were killed on day 14 (Group OTW). Oxytocin receptor concentrations and localization in the endometrium and myometrium were measured by radioreceptor assay, in situ hybridization and autoradiography with the iodinated oxytocin receptor antagonist d(CH2)5[Tyr(Me)2,Thr4,Tyr-NH2(9)]-vasotocin. Oestradiol and progesterone receptors were localized by immunocytochemistry. Oxytocin receptors were present in the luminal epithelium and superficial glands of ovariectomized ewes. In Group O, endometrial oxytocin receptor concentrations were high (1346 +/- 379 fmol [3H]oxytocin bound mg protein-1) and receptors were also located in the deep glands and caruncular stroma in a pattern resembling that found at natural oestrus. Continuing low-dose oestradiol was unable to sustain high endometrial oxytocin receptor concentrations with values decreasing significantly to 140 +/- 20 fmol mg protein-1 (P < 0.01), localized to the luminal epithelium and caruncular stroma but not the glands. Progesterone treatment initially abolished all oxytocin receptors with none present on days 8 or 10. They reappeared in the luminal epithelium only between days 12 and 14 to give an overall concentration of 306 +/- 50 fmol mg protein-1. Oxytocin treatment caused a small increase in oxytocin receptor concentration in the luminal epithelium on days 8 and 10 (20 +/- 4 in Group P and 107 +/- 35 fmol mg protein-1 in Group OT, P < 0.01) but the rise on day 14 was not affected (267 +/- 82 in Group OT and 411 +/- 120 fmol mg protein-1 in Group OTW). In contrast, oestradiol treatment was able to sustain myometrial oxytocin receptors (635 +/- 277 fmol mg protein-1 in Group O and 255 +/- 36 in Group E) and there was no increase over time in Groups P, OT and OTW with values of 61 +/- 18, 88 +/- 53 and 114 +/- 76 fmol mg protein-1 respectively (combined values for days 8-14). Oestradiol receptor concentrations were high in all uterine regions in Group O. This pattern and concentration was maintained in Group E. In all progesterone-treated ewes, oestradiol receptor concentrations were lower in all regions at all time-points. The only time-related change occurred in the luminal epithelium in which oestradiol receptors were undetectable on day 8 but developed by day 10 of progesterone treatment. Progesterone receptors were present at moderate concentrations in the deep glands, caruncular stroma, deep stroma and myometrium in Group O. Oestradiol increased progesterone receptors in the luminal epithelium, superficial glands, deep stroma and myometrium. Progesterone caused the loss of its own receptor from the luminal epithelium and superficial glands and decreased its receptor concentration in the deep stroma and myometrium at all time-points. There was a time-related loss of progesterone receptors from the deep glands of progesterone-treated ewes between days 8 and 14. These results show differences in the regulation of receptors between uterine regions. In particular loss of the negative inhibition by progesterone on the oxytocin receptor by day 14 occurred only in the luminal epithelium, but is unlikely to be a direct effect of progesterone as no progesterone receptors were present on luminal epithelial cells between days 8 and 14.

The effect of oxytocin and oestradiol on the action of conceptus secretory protein in progesterone-treated ovariectomized ewes

In intact cyclic ewes intrauterine infusion of conceptus secretory proteins results in the suppression of both endometrial oxytocin receptor concentrations and oxytocin-induced prostaglandin F2 alpha release. However, similar infusion in progesterone-treated ovariectomized ewes, while suppressing endometrial oxytocin receptors, does not fully inhibit oxytocin-induced prostaglandin F2 alpha release. To examine whether this anomaly resulted from an inadequate simulation of the luteal phase in the ovariectomized ewe treated with progesterone alone, the effects of additional treatment with two other ovarian hormones, oestradiol-17 beta and oxytocin, was investigated. Rather than permitting conceptus secretory protein to successfully inhibit oxytocin-induced prostaglandin F2 alpha release, treatment with oestradiol-17 beta in addition to progesterone actually resulted in an advancement in the timing of release. However, treatment with oxytocin, alone or in combination with oestradiol, permitted the full inhibition of oxytocin-induced prostaglandin F2 alpha release. To confirm that this effect did not result from the action of oxytocin alone, independently of the action of conceptus secretory protein, a second experiment was undertaken using a similar protocol but without the infusion of conceptus secretory protein. In this situation, oxytocin-induced prostaglandin F2 alpha release was only partially inhibited suggesting that both luteal oxytocin and conceptus secretory proteins are necessary to facilitate the full inhibition of luteolysis during early pregnancy in the ewe.

Endoscopic surgery teleconferencing

Modern telecommunication allowing the transmission of digitalized voice and images through telephone lines has expanded to medicine. The Integrated Digital Network System (ISDN) can be used to transmit 128 kbit/sec (ISDN-2) to 2 Mbit/sec (ISDN-30). Together with smart compression techniques a teleconferencing system can be implemented to transmit images of an endoscopic operation. In this paper 2 such experiments are described. In the first experiment a laparoscopic cholecystectomy performed in the Netherlands is followed at the same time by surgeons in Hawaii through ISDN-2 lines. In the second experiment a laparoscopic hernia repair was followed in Orlando during a congress using ISDN-6 lines. The images sent over the ISDN-2 lines are rather blurry with rapid movement. The images over the ISDN-6 lines were more acceptable. Data compression and decompression results in a time delay of approximately 1 second, which seems not disturbing during the connection. The cost of communication is comparable to telephone communication, which makes this form of telecommunication feasible in surgical practice.

Local action of trophoblast interferons in suppression of the development of oxytocin and oestradiol receptors in ovine endometrium

Luteolysis in sheep is associated with uterine secretion of pulses of prostaglandin F2 alpha (PGF2 alpha) due to the action of luteal oxytocin on endometrial oxytocin receptors. For pregnancy to become established inhibition of oxytocin receptors is important as an antiluteolytic mechanism. The maternal recognition of pregnancy in cattle and sheep involves production, by the trophoblast, of a type 1 interferon (IFN-tau) that suppresses uterine development of oxytocin receptors and the generation of luteolytic episodes of PGF2 alpha. The action of IFN-tau in surgically prepared unilaterally pregnant ewes was investigated. Finn-Dorset ewes were anaesthetized on day 6 or 7 of the oestrous cycle and one uterine horn was surgically isolated at the uterine bifurcation from the body of the uterus. Ewes were mated at the subsequent oestrus either by a fertile or by a vasectomized ram and killed on day 13 or 16 after mating. On day 16, in the non-pregnant ewes, there was no measurable uterine IFN-tau but there were high concentrations of oxytocin receptors in both horns. In the pregnant ewes on day 16 after mating, the oxytocin receptor concentration was 45 +/- 11 fmol mg-1 protein in the pregnant horn and 585 +/- 131 fmol mg-1 in the non-pregnant horn. Antiviral activity was 5.8 x 10(7) +/- 5.2 x 10(7) U ml-1 in the pregnant horn and 2.9 x 10(3) +/- 1.2 x 10(3) U ml-1 in the non-pregnant horn. Thus, 16 days after mating, the pregnant horn exhibited high antiviral activity but oxytocin receptors were suppressed, while in the same endocrine environment (characteristic of pregnancy) there were low IFN-tau and high oxytocin receptor concentrations in the isolated horn equivalent to those expected at the onset of luteolysis. In situ hybridization to ovine mRNA encoding the oxytocin receptor and autoradiographic studies using the 125I-labelled oxytocin antagonist d(CH2)5[Tyr(Me)2,Thr4,Tyr-NH2(9)]-vasotocin both showed that the large amount of oxytocin receptor message and binding sites in the endometrium of the isolated horn were localized in the luminal epithelium. Immunocytochemical studies showed that there was a suppression of oestradiol receptors in the pregnant horn but high concentrations equivalent to those at oestrus were present in the isolated horn. The content of progesterone receptors was low in the stromal tissue only in both horns, a pattern of localization similar to that seen in the late luteal phase and in early pregnancy.(ABSTRACT TRUNCATED AT 400 WORDS)

Teleconferencing bridges two oceans and shrinks the surgical world

Endoscopic surgery has led to changes in surgical practice which may rival the introduction of anesthesia and antibiotics in significance. As a result, an exciting synergy has rapidly emerged between technology and clinical practice. However, questions of training, credentialing, and patient safety have been raised as traditional procedures have been adapted to the minimally invasive approach and new ones are described. Many surgeons have been reluctant to venture beyond laparoscopic cholecystectomy. Halting first efforts at advanced procedures may prolong operative times, increase risk, and raise costs. Older methods of surgical education are not adequate to meet the current need (Fig. 1).

Laparoscopic or open inguinal herniorrhaphy? A randomized prospective trial

OBJECTIVE

To determine whether transabdominal preperitoneal laparoscopic hernia repair can equal or surpass an established open method at an acceptable cost.

DESIGN

A randomized, prospective comparison with a follow-up of 7 to 18 months (median, 10 months; planned, 5 years).

SETTING

Health maintenance organization hospital.

PATIENTS

One hundred patients between 20 and 70 years of age were randomized. No patient withdrew from the study after randomization.

INTERVENTIONS

Transabdominal preperitoneal laparoscopic and open tension-free repairs using a polypropylene mesh.

MAIN OUTCOME MEASURES

Operative and discharge times, costs, recovery, and morbidity. "Return to work" was supplemented by a performance assessment using a panel of exercises.

RESULTS

Operative and hospitalization times were not significantly different between the two types of repair. Patients with laparoscopic unilateral repairs returned to work faster (9 vs 17 days). At 1 week postoperatively, performance of straight-leg raises correlated well with time to return to work for patients with strenuous jobs. The laparoscopic repair was more expensive than the open approach ($3093 vs $2494).

CONCLUSIONS

Laparoscopic transabdominal preperitoneal hernia repair can be accomplished with operative and hospitalization times and a short-term recurrence rate similar to those of an established open technique. Perioperative exercise testing may be an important adjunct to return to work in the comparison of methods.

The direct influence of the embryo on uterine PGF2 alpha and PGE2 production in sheep

In unilateral pregnant ewes, obtained by surgically transecting one uterine horn to isolate it from the rest of the pregnant uterus, the isolated horn develops endometrial oxytocin receptors by day 16 despite being in a hormonal environment equivalent of that of a pregnant ewe. This study examines uterine prostaglandin production in these animals. On day 16 of pregnancy, ewes were anaesthetized and a uterine vein draining each horn and the jugular vein cannulated. Venous blood samples were taken at 10 min intervals for 1 h before and 1 h after an i.v. injection of oxytocin (1 microgram). Uterine vein samples were assayed for PGF2 alpha and PGE2 and jugular blood samples assayed for 13,14-dihydro,15-keto-PGF2 alpha. All ewes showed high plasma concentrations of 13,14-dihydro,15-keto-PGF2 alpha after the oxytocin injection. PGF2 alpha increased in the uterine vein draining the nonpregnant transected horn of a unilaterally pregnant ewe following oxytocin treatment, whereas there was no increase in concentration in plasma draining the pregnant horn. Basal plasma PGF2 alpha concentrations from the uterine vein draining the pregnant horn were significantly higher than concentrations obtained from the uterine vein of the transected horn while PGE2 concentrations did not vary between the two horns. After oxytocin injection, there was a significant increase in plasma PGE2 concentration in venous blood collected from both sides.(ABSTRACT TRUNCATED AT 250 WORDS)

Ultrasonic dissection

Following its development for cataract surgery, and gaining widespread use in neurosurgery and liver resection, ultrasonic dissection has been adapted for laparoscopic use. The turbulence, heat, and pressure generated by imploding bubbles disrupts tissues high in water content. This phenomenon is called cavitation and is the principal means by which ultrasonic dissection is accomplished. A randomized, prospective trial demonstrated the utility of the device for laparoscopic cholecystectomy. It was particularly effective in the presence of acute periportal inflammation or fat. Additional experience with a wide range of laparoscopic procedures is being accumulated by several investigators around the world. The laparoscopic use of ultrasonic dissection will be most valuable whenever selective, precise, and, therefore, safe dissection is desired.

Insensitivity of dispersed caprine luteal cells to β-adrenergic agonists and other putative transmitter substances

Adrenaline (10(-6)-10(-4)M), serotonin (10(-6)-10(-4)M), and several other potential steroidogenic agonists failed to enhance either basal or LH-stimulated progesterone production from dispersed caprine luteal cells from Day 10 of the estrous cycle. The caprine corpus luteum (CL) would appear to be more refractory to exogenous stimulation than either the ovine or bovine CL.

Pulsatile release of oxytocin after suppression of prostaglandin synthesis in hysterectomised ewes

On days 13 and 14 after oestrus (day 0) oxytocin and 13,14-dihydro-15-keto-prostaglandin (PG)F2 alpha (PGFM) concentrations were measured in jugular plasma of hysterectomised sheep with or without systemic treatment with the PG cyclo-oxygenase inhibitor indomethacin (4 mg kg-1 three times a day on days 12, 13 and 14 subcutaneously. Pulsatile increases of oxytocin were observed in both untreated and treated sheep with mean (+/- SD) peak heights of 18.4 +/- 9.6 pg ml-1 (n = 11) and 23.5 +/- 9.4 pg ml-1 (n = 8), respectively; these means were not significantly different. Plasma concentrations of PGFM remained consistently low in both groups (under 100 pg ml-1) with no significant peaks observed. The data suggest that PGF2 alpha may not be the only stimulus for the release of luteal oxytocin, or that there may be a contribution by the posterior pituitary to oxytocin secretion during the luteal phase of the ovine oestrous cycle.

Direct stimulation of bovine ovarian progesterone secretion by low concentrations of alpha-interferon

The ruminant conceptus secretes proteins during early pregnancy which maintain the corpus luteum. These trophoblast proteins are related to the alpha II-interferons and prevent luteolysis indirectly by disrupting the secretion of endometrial prostaglandin. Although trophoblast interferons appear to be largely confined to the uterine lumen, it remains possible that they also act peripherally. This report describes in vitro studies which suggest that interferon may influence hormone secretion by the ovary directly. The study employed i) a well defined serum-free culture model in which bovine granulosa cells secrete the luteal hormones progesterone and oxytocin, and ii) serum-free and serum-supplemented cultures of cells from early CL. Dose-response experiments were performed using bovine recombinant alpha-interferon (brIFN). Progesterone and oxytocin secretions were measured over 4-5 days of culture and DNA content was also determined. Low concentrations of brIFN (10(-15) mol/l to 10(-11) mol/l) stimulated progesterone secretion by granulosa cells by up to three fold, without significantly affecting oxytocin concentrations or culture DNA content. Concentrations of 10(-10) mol/l to 10(-1) mol/l suppressed progesterone secretion in a log dose-related manner (r = 0.97) with evidence of toxicity (lower oxytocin concentrations and significantly reduced DNA compared with controls). Progesterone secretion by luteal cells in serum-free culture was stimulated in the presence of 10(-15) mol/l brIFN, whilst high concentrations again caused inhibition. The data show that ovarian cells can respond directly to low concentrations of interferon-like proteins.(ABSTRACT TRUNCATED AT 250 WORDS)

The ultrasonic dissector facilitates laparoscopic cholecystectomy

The ultrasonic dissector disrupts tissues in proportion to their fluid content by ultrasonically induced cavitational forces. Since sturdy tissues are spared, the instrument tends to follow tissue planes and to dissect fat and other soft tissues selectively. We performed a prospective, randomized, controlled trial in 73 patients comparing the safety and efficacy of a prototype ultrasonic dissector with that of electrosurgery and laser during laparoscopic cholecystectomy. Randomization was as follows: ultrasonic dissector, 37 patients; electrosurgery, 21 patients; and laser, 15 patients. The results were not different with respect to patient characteristics, amount of blood loss, technical difficulties, length of hospital stay, or return to work. Subjectively, the ultrasonic dissector was thought to be of special value in isolating the hilar structures, particularly when they were edematous or embedded in fat. The ultrasonic dissector disintegrated the fat, which was rapidly cleared up the suction channel, allowing the cystic duct and artery to be bared with less risk of injury. We concluded that the ultrasonic dissector has unique attributes that contribute to the ease and safety of laparoscopic cholecystectomy.

Repair and regeneration: experimental aspects of spinal cord disease

Regeneration of spinal cord neurons after injury depends on first, the presence of trophic factor(s) which prevent death, induce growth and maintain the viability of the neurone and second, the regenerating neurites must overcome glial scars, extracellular matrices and white matter barriers to reinnervate their target. Attempts at promoting regeneration by using grafts of prosthetic material, Schwann cells and neural tissue have largely been unsuccessful. Although growth could be induced, penetration of regenerating neurites through damaged areas of the spinal cord has been limited. There is as yet very little beneficial functional recovery.

The effects of adrenaline and atropine on oxytocin-induced estrus in the goat

Oxytocin-induced luteolysis in goats was associated with significant increases in peripheral plasma concentrations of 13,14-dihydro-15-keto-prostaglandin (PG) F(2alpha) (PGFM). This effect was not inhibited by concomitant administration of adrenaline (1 mg), although increases of PGFM were both delayed and diminished. Administration of atropine, a muscarinic cholinergic antagonist, inhibited the effect of oxytocin in three out of five goats. In these animals, increases in PGFM were inhibited.

Effect of oxytocin on plasma concentrations of 13,14-dihydro-15-keto-prostaglandin F2 alpha during the oestrous cycle and early pregnancy in the goat

The effect of subcutaneous oxytocin on plasma concentrations of 13,14-dihydro-15-keto-prostaglandin (PG) F2 alpha (PGFM) was examined in the goat at various periods during the oestrous cycle and early pregnancy. 100 i.u. oxytocin was administered daily for 4 day, the dose being divided and given at 0900 and 2100 h; PGFM concentrations were assessed after the first treatment of each day. On days 3-6 (oestrus, day 0) PGFM concentrations increased significantly (P less than 0.001) within 15 minutes and both non-pregnant and mated goats exhibited oestrus behaviour by day 7. Significant (P less than 0.01) increases in PGFM were also produced on days 7-10, in both non-pregnant and pregnant goats, but the responses diminished from day 7 to day 10; only one goat (non-pregnant) came into oestrus. There was a marked difference in response between groups, however, during days 12-15. In non-pregnant goats significant (P less than 0.05) increases in PGFM were detected on days 13-15, but in pregnant animals oxytocin was without effect. Similarly, oxytocin did not increase PGFM concentrations on days 17-20 of pregnancy. However, uterine responsiveness reappeared in pregnant goats with significant (P less than 0.01) increases in PGFM on days 24 and 25.

Multiplication and Virulence in Plant Tissues of Escherichia coli Clones Producing Pectate Lyase Isozymes PLb and PLe at High Levels and of an Erwinia chrysanthemi Mutant Deficient in PLe

The phytopathogenic enterobacterium Erwinia chrysanthemi strain EC16 produces four isozymes of pectate lyase (PL), an extracellular enzyme that macerates parenchymatous plant tissues and kills plant cells. A 1.8-kilobase Eco RI DNA fragment containing the entire pelE gene was deleted from the E. chrysanthemi chromosome by marker exchange of a cloned fragment that had been modified in vitro. The resulting mutant, UM1001, produced the isozymes PLa, PLb, and PLc, but not PLe. Mutant UM1001 was compared with wild-type E. chrysanthemi , with Escherichia coli JA221, and with JA221 containing expression vectors with cloned pel genes producing high levels of PLe (pPEL748) or PLb (pPEL343) for the ability to multiply and cause symptoms in intact potato tubers. Tubers were injected with less than 100 bacteria per inoculation site and incubated aerobically or anaerobically. While maceration occurred only in anaerobically incubated tubers, all of the bacteria, including nonpectolytic E. coli controls, multiplied substantially under all conditions. E. coli JA221(pPEL748) caused significantly more maceration than E. coli JA221(pPEL343) or wild-type E. chrysanthemi. Mutant UM1001 caused significantly less maceration than the wild-type E. chrysanthemi. The results establish the importance of PLe in the pectolytic arsenal of E. chrysanthemi by demonstrating that production of PLe can enable E. coli to aggressively macerate tuber tissue and that deletion of pelE significantly diminishes the virulence of E. chrysanthemi.

Responses of Rj(1) and rj(1) Soybean Isolines to Inoculation with Bradyrhizobium japonicum

We evaluated the symbiotic phenotypes of nodulation-restrictive and normal soybean isolines by inoculating Clark (genotypically Rj(1)Rj(1)) and mutant Clark-rj(1) (genotypically rj(1)rj(1)) seedlings in plastic growth pouches. Nodules first appeared on Clark seedlings inoculated with Bradyrhizobium japonicum USDA 94 after 6 days. The mean number of nodules per plant was 13.9 +/- 0.8 after 24 days. In contrast, Clark-rj(1) seedlings first nodulated at 12 days, and the mean number of nodules per plant was only 1.7 +/- 0.3 at 24 days. Segments from infectible zones of primary roots, i.e. near the position occupied by the root tip at the time of inoculation, were sectioned serially. Clark roots contained cortical cell divisions and a few infection threads in question mark-shaped root hairs by 2 days after inoculation. Typical nodules developed soon thereafter. Analogous serially sectioned segments from Clark-rj(1) roots lacked these responses. This prompted us to section nodules and adjacent tissues from other parts of Clark and Clark-rj(1) roots. Clark roots contained cortical cell divisions, many associated with infected root hairs. Cortical cell divisions occasionally were present in Clark-rj(1), and a few infection threads were visible in surface cells. The presence of infection threads within Clark-rj(1) nodules was confirmed by transmission electron microscopy. Thus, although B. japonicum USDA 94 fails to elicit the wild-type spectrum of responses in the infectible zones of primary roots, it can infect Clark-rj(1) via infection threads.

Rickets in premature infants fed different formulas

To study the role of formula as a cause of rickets, we randomly assigned 46 very-low-birth-weight (VLBW) infants (less than or equal to 1,500 gm) to one of three groups receiving either Isomil, a soy isolate formula, Similac with Iron, a common milk-based formula, or Similac 24 LBW, a hypercaloric milk-based formula designed for low-birth-weight infants during the first three to four months of life. Postnatal changes in serum calcium, phosphorus, alkaline phosphatase, and albumin were monitored during this study. Radiologic diagnosis of rickets was made in 60% of infants fed Isomil and 5% fed Similac with Iron. Significantly low levels of serum phosphorus and high levels of serum alkaline phosphatase were also seen in infants fed Isomil. The exact cause of the biochemical changes and the high incidence of rickets among infants fed Isomil is not clear. Poor solubility and possibly the decreased bioavailability of minerals in soy isolate formula may be important. We conclude that rickets occurs with high frequency among VLBW infants fed soy isolate, but not milk-based formulas. We suggest that prolonged feeding of soy isolate formulas should be avoided in VLBW infants.

The preoperative detection of axillary lymph node metastases in breast cancer by isotope imaging

Axillary lymphoscintigraphy using 99Tcm-labelled liposomes was carried out in 40 patients with breast cancer as a part of pretreatment staging in an attempt to improve the accuracy of axillary evaluation. Patients were injected interstitially in the periareolar region of each breast with 250–300 μCi of 99Tcm-labelled liposomes. Subsequently the patients were imaged with a gamma-camera using computerized data processing. Interpretation of images was based on prior experimental data; a diminished uptake of isotope by the primary regional lymph node (PRLN) and the group of axillary regional lymph nodes (RLN) draining the tumour, when compared to the control side, was considered to be abnormal and to suggest node metastases. An equal or enhanced uptake by the PRLN or RLN draining the tumour, when compared to the control side, was considered normal, indicating an absence of lymph node metastases. Eighteen patients (45 per cent) had abnormal scans and 14 patients (35 per cent) had normal scans. Eight patients (20 per cent) had technically unsatisfactory images where axillary nodes could not be identified. Twenty-two patients of the 32 with evaluable scans had correlation of preoperative images with postsurgical axillary lymph node histopathology. One patient out of 12 with an abnormal scan had normal lymph nodes on serial sectioning, and 2 patients out of 10 with normal scans had lymph node metastases. Eight of the 32 patients (25 per cent) with evaluable images had enhanced uptake of isotope by the PRLN and RLN draining the tumour. In 3 of these cases a marked reactive hyperplasia only was shown on histopathological examination, in 2 cases the reactive hyperplasia was associated with lymph node metastases, accounting for the 2 false negative interpretations. This preliminary study suggests that axillary lymphoscintigraphy may be of value in preoperative staging in breast cancer. Long term studies are needed to evaluate the prognostic potential of such a test as a measure of macrophage function. Further studies, by blind replication, are required to evaluate the accuracy of axillary lymph node imaging.

Traumatic diaphragmatic hernia

The records of 36 patients with traumatic diaphragmatic hernia (TDH) were reviewed. In 14, acute hernias were diagnosed, but the diagnosis was made one month to 15 years after injury in 22 patients with chronic hernia. Seven acute TDHs were due to blunt and seven to penetrating trauma. Four chronic TDHs were due to blunt and 18 to penetrating trauma. Chest pain, abdominal pain, or dyspnea occurred in each acute case and in 18 of 22 chronic cases. Plain chest roentgenograms were abnormal in 33 of 36 cases. Pleural effusion or abnormal diaphragmatic contour were common abnormal findings. Supradiaphragmatic bowel, pathognomonic of TDH, was evident in seven acute and eight chronic hernias. Celiotomy was routinely employed in acute hernias, celiotomy or thoracotomy in chronic hernias. There were three deaths, two with associated CNS injury and one with chronic pulmonary disease.