ARS Presidential Address: Estrogen therapy: a causal role in endometrial cancer?

Publicity associated with recent reports of a greater frequency of adenocarcinoma of the endometrium among women who take exogenous estrogens has created confusion among physicians and fear among patients. An objective review of available data on estrogen effects and current epidemiologic evidence suggests that estrogen may play an indirect role in the development of endometrial carcinoma. Until definitive data are available, physicians should exercise caution in prescribing estrogens, monitoring the status of the endometrium at regular intervals by sampling and pathologic analysis.     

Cyclic changes of cervical mucus enzymes related to the time of ovulation. I. Alkaline phosphatase

The concentration of alkaline phosphatase in cervical mucus was serially determined during a menstrual cycle in five normal ovulatory women and correlated with the time of ovulation as monitored by the basal body temperature and radioimmunoassay of serum lutenizing hormone (LH), progesterone, and estradiol. The activity of alkaline phosphatase decreased significantly at midcycle just prior to the LH surge and began to rise after ovulation. Self-detection of cervical mucus alkaline phosphatase may provide a practical method of ovulation prediction.     

Effects of elevated concentrations of prostaglandin F2 alpha on pregnancy rates in progestogen supplemented cattle

An experiment was performed to determine the effect of elevated prostaglandin F2 alpha (PGF2 alpha) on pregnancy rates of progestogen-treated bred cows in the presence or absence of luteal tissue. Ninety-one beef cows were bred (Day 0) and assigned randomly to receive either 3 mL saline (CON), 15 mg PGF2 alpha, or 15 mg PGF2 alpha + lutectomy (P + L) administered intramuscularly (i.m.) at 8 h intervals on either Days 5-8, 10-13, or 15-18 postbreeding. Lutectomies were performed by transrectal digital pressure before initiation of treatment on Day 5, 10, or 15 for the respective treatment groups. All cows were fed 4 mg/day of melengesterol acetate from two days prior to initiation of treatment until Day 30 postbreeding. Mean concentrations of 13,14-dihydro-15-keto-PGF2 alpha (PGFM) were increased in cows administered PGF2 alpha and P + L treatments (398 +/- 23 and 413 +/- 22 pg/ml, respectively; p < 0.01) compared to the CON group (80 +/- 29 pg/ml) regardless of treatment group. Mean concentrations of oxytocin (OT) were increased in cows given PGF2 alpha on Day 10 and 15 (p < or = 0.0001) and tended to be increased on d 5 when compared to CON and P + L treatment groups on Day 5. Pregnancy rates were reduced (p < or = 0.03) in the PGF2 alpha treatment group (23%) and by Day 5-8 compared to CON (72%). Lutectomy tended to improve pregnancy rate in P + L (5-8; 55%) compared to PGF2 alpha (5-8; p = 0.1). Pregnancy rates tended (p < or = 0.07) to increase in the PGF2 alpha treatment groups on Days 5-8 treatment (23%, 50%, and 60% for Days 5-8, 10-13, and 15-18, respectively). The later the treatments were initiated pregnancy rates did not differ between treatments given on Days 10-13 and 15-18. In conclusion, the most susceptible period of embryonic growth to the negative effects of PGF2 alpha was during morula to blastocyst development. Removal of luteal tissue diminishes the negative effects of PGF2 alpha through interruption of the luteal oxytocin-uterine PGF2 alpha feedback loop.     

Effect of the extramitochondrial adenine nucleotide pool size on oxidative phosphorylation in isolated rat liver mitochondria

We report a long-term follow-up of abduction-extension osteotomy of the first metacarpal, performed for painful trapeziometacarpal osteoarthritis. Of a consecutive series of 50 operations, 41 thumbs (82%) were reviewed at a mean follow-up of 6.8 years. Good or excellent pain relief was achieved in 80%, and 93% considered that surgery had improved hand function, while 82% had normal grip and pinch strength, with restoration of thumb abduction. Metacarpal osteotomy was equally successful in relieving symptoms of those with early (grade 2) and moderate (grade 3) degenerative changes. This simple procedure provides lasting pain relief, corrects adduction contracture and restores grip and pinch strength, giving good results with few complications.     

Endotoxin release and cytokine production in acute and chronic meningococcaemia

Muscle activity produces an electrical signal termed the myo-electric signal (MES). The MES is a useful clinical tool, used in diagnostics and rehabilitation. This signal is typically stored in 2 bytes as 12-bit data, sampled at 3 kHz, resulting in a 6 kbyte s-1 storage requirement. Processing MES data requires large bit manipulations and heavy memory storage requirements. Adaptive differential pulse code modulation (ADPCM) is a popular and successful compression technique for speech. Its application to MES would reduce 12-bit data to a 4-bit representation, providing a 3:1 compression. As, in most practical applications, memory is organised in bytes, the realisable compression is 4:1, as pairs of data can be stored in a single byte. The performance of the ADPCM compression technique, using a real-time system at 1 kHz, 2 kHz and 4 kHz sampling rates, is evaluated. The data used include MES from both isometric and dynamic contractions. The percent residual difference (PRD) between an unprocessed and processed MES is used as a performance measure. Errors in computed parameters, such as median frequency and variance, which are used in clinical diagnostics, and waveform features employed in prosthetic control are also used to evaluate the system. The results of the study demonstrate that the ADPCM compression technique is an excellent solution for relieving the data storage requirements of MES both in isometric and dynamic situations.     

Acidosis in cattle: a review

Acute and chronic acidosis, conditions that follow ingestion of excessive amounts of readily fermented carbohydrate, are prominent production problems for ruminants fed diets rich in concentrate. Often occurring during adaptation to concentrate-rich diets in feedyards, chronic acidosis may continue during the feeding period. With acute acidosis, ruminal acidity and osmolality increase markedly as acids and glucose accumulate; these can damage the ruminal and intestinal wall, decrease blood pH, and cause dehydration that proves fatal. Laminitis, polioencephalomalacia, and liver abscesses often accompany acidosis. Even after animals recover from a bout of acidosis, nutrient absorption may be retarded. With chronic acidosis, feed intake typically is reduced but variable, and performance is depressed, probably due to hypertonicity of digesta. Acidosis control measures include feed additives that inhibit microbial strains that produce lactate, that stimulate activity of lactate-using bacteria or starch-engulfing ruminal protozoa, and that reduce meal size. Inoculation with microbial strains capable of preventing glucose or lactate accumulation or metabolizing lactate at a low pH should help prevent acidosis. Feeding higher amounts of dietary roughage, processing grains less thoroughly, and limiting the quantity of feed should reduce the incidence of acidosis, but these practices often depress performance and economic efficiency. Continued research concerning grain processing, dietary cation-anion balance, narrow-spectrum antibiotics, glucose or lactate utilizing microbes, and feeding management (limit or program feeding) should yield new methods for reducing the incidence of acute and chronic acidosis.     

Bowel endometriosis. Eight cases of colorectal resection

Colo-rectal endometriosis requiring colon resection are reported in 8 patients to illustrated the diagnostic and therapeutic problems encountered in the management of this uncommon localisation. Pericatamenial or catamenial bowel symptoms associated with pelvic genital involvement were encountered in all cases. Clinical examination, barium enema and colonoscopy are essential to guide surgical management looking for multiple localisations. However their diagnostic value is low as endometriosis rarely involves the mucosa. Endosonography appears to be very promising in evaluating the depth of infiltration of the bowel. The treatment of bowel endometriosis is controversial and varies greatly according to the patient's complaints and clinical data. The indications and limits of all treatment modalities including abstention, medical, and surgical treatment are discussed. From the cases reported we conclude that symptomatic bowel endometriosis should be fully excised whenever possible, and the surgical procedure should be adapted to the depth of infiltration. A full thickness excision or bowel resection is mandatory in patients with deep muscularis involvement. These procedures, which are often difficult due to extensive fibrosis and adhesions, may be achieved by laparoscopy in selected patients.