Ankle fractures in diabetic neuropathic arthropathy

Between 2000 and 2006 we performed salvage tibiotalar arthrodesis in 17 diabetic patients (17 ankles) with grossly unstable ankles caused by bimalleolar fractures complicated by Charcot neuro-arthropathy. There were ten women and seven men with a mean age of 61.6 years (57 to 69). A crossed-screw technique was used. Two screws were used in eight patients and three screws in nine. Additional graft from the malleoli was used in all patients. The mean follow-up was 26 months (12 to 48) and the mean time to union was 5.8 months (4 to 8). A stable ankle was achieved in 14 patients (82.4%), nine of whom had bony fusion and five had a stiff fibrous union. The results were significantly better in underweight patients, in those in whom surgery had been performed three to six months after the onset of acute Charcot arthropathy, in those who had received anti-resorptive medication during the acute stage, in those without extensive peripheral neuropathy, and in those with adequate peripheral oxygen saturation (> 95%). The arthrodesis failed because of avascular necrosis of the talus in only three patients (17.6%), who developed grossly unstable, ulcerated hindfeet, and required below-knee amputation.

Histological, histochemical and electron microscopic changes of the placenta induced by maternal exposure to hyperthermia in the rat

Both clinical and experimental investigations have shown that maternal hyperthermia during critical stages of embryo development can induce malformations in the offspring. Studies of the effect of heat stress on the placental functions are limited to the ewes, but that on microscopic structure is unknown. In the present study, rats were exposed to 41 or 42 degrees C for 1 h on gestation day (GD) 9. The controls were sham treated. Fetuses and placentas were collected on GD 20. Intrauterine growth retardation (IUGR) and several craniofacial malformations were observed in the fetuses of the heat-treated group. The placentas of the 42 degrees C group were significantly lighter in weight than those of the control. Light microscopy (LM) revealed thickening, hyalinization and occasional lymphocytic infiltration of the decidua basalis. Giant cells were prominent and glycogen cells had degenerated, leaving behind large cysts in the basal (spongy) zone. Best's carmine stain with or without diastase indicated the reduction in number and degeneration of glycogen cells and cyst formation. The labyrinthine zone was relatively thin in comparison to that of the controls. Perivascular fibrosis and paucity of vascularization were other features of the placentas of the hyperthermia group. Electron microscopy (EM) revealed lipid droplet accumulation in the trophoblast, the presence of myelin bodies and an increased production of collagen in the basal zone. Perivascular fibrosis appeared to have contributed to placental barrier thickening. EM also revealed accumulation of glycogen and lipid droplets in the trophoblasts and fibrin secretion into the extracellular space of the labyrinthine zone. These data suggest that placental pathology possibly contributes to fetal growth retardation in maternally heat-stressed rat fetuses.

First-trimester embryo size discordance: a predictor of premature birth following multifetal pregnancy reduction

OBJECTIVE

We have previously reported a correlation between the starting number of embryos for multifetal pregnancy reduction (MFPR) and discordance in size during the first trimester. Here we evaluated the correlation between the degree of discordance and length of gestation in the remaining fetuses.

DESIGN

Observational clinical series.

SETTING

Academic medical center with a single physician who performs a large number of MFPRs.

PATIENT(S)

Analysis of 252 consecutive MFPRs from a 2.5-year period (1996-1998).

INTERVENTION(S)

MFPR for patients with multifetal pregnancies.

MAIN OUTCOME MEASURE(S)

We evaluated the correlation between the degree of discordance in embryo size, as measured by the greatest difference in crown-rump length (CRL) (delta max), and the length of gestation.

RESULT(S)

Embryo size discordance was related to length of gestation of the remaining fetuses after MFPR. Of 72 patients with a delta max >5 mm, the rate of severe premature birth (delivery at <28 weeks' gestation) was 9.7%, compared with 1.7% for patients with a delta max <5 mm (P<.01). Of patients with severe premature birth, 70% had delta max >5 mm, compared with less than 30% in patients who delivered after 28 weeks (P<.05).

CONCLUSION(S)

Variations in embryo growth patterns in multifetal pregnancies may be observed even in the first trimester, which may be predictive of late pregnancy outcomes. With a delta max > or =5 mm, there is a significant increase in the risk of severe premature birth (delivery at <28 weeks).

Improvement in outcomes of multifetal pregnancy reduction with increased experience

OBJECTIVE

This study was undertaken to evaluate a decade of data on multifetal pregnancy reductions at centers with extensive experiences.

STUDY DESIGN

A total of 3513 completed cases from 11 centers in 5 countries were analyzed according to year (before 1990, 1991-1994, and 1995-1998), starting and finishing numbers of embryos or fetuses, and outcomes.

RESULTS

With increasing experience there has been a considerable improvement in outcomes, with decreases in rates of both pregnancy loss and prematurity. Overall loss rates in the last few years were correlated strongly with starting and finishing numbers (starting number > or =6, 15.4%; starting number 5, 11.4%; starting number 4, 7.3%; starting number 3, 4.5%; starting number 2, 6.2%: finishing number 3, 18.4%; finishing number 2, 6.0%; finishing number 1, 6.7%). Birth weight discordance between surviving twins was increased with greater starting number. The proportion of cases with starting number > or =5 diminished from 23.4% to 15.9% to 12.2%. The proportion of patients >40 years old increased in the last 6 years to 9.3%. Gestational age at delivery did not vary with increasing maternal age but was inversely correlated with starting number.

CONCLUSION

Multifetal pregnancy reduction outcomes at our centers for both losses and early prematurity have improved considerably with experience. Reductions from triplets to twins and now from quadruplets to twins carry outcomes as good as those of unreduced twin gestations. Patient demographic characteristics continues to change as more older women use assisted reproductive technologies. In terms of losses, prematurity, and growth, higher starting numbers carry worse outcomes.

Fiscal impact of a potential legislative ban on second trimester elective terminations for prenatally diagnosed abnormalities

This study was designed to determine the fiscal impact of a theoretical legislative ban on elective terminations for prenatally diagnosed abnormalities at Hutzel Hospital/Wayne State University. A fiscal comparison was completed for patients who had second trimester elective terminations for prenatally diagnosed abnormalities versus not allowing the procedure. An eight-year database of genetics cases and hospital and physician cost estimates for performing elective terminations for prenatally diagnosed abnormalities, and published reports of the average lifetime costs per selected birth defects, were used to calculate the net cost. The estimated lifetime cost for an average cohort year of a legislative ban on elective terminations for prenatally diagnosed abnormalities was found to be at least $8.5 million for patients treated at Hutzel Hospital. Extrapolated, a similar ban on second trimester elective terminations would have a net cost of $74 million in Michigan and $2 billion annually in the United States.

Selective termination for structural, chromosomal, and mendelian anomalies: international experience

OBJECTIVE

Our purpose was to evaluate the outcomes of selective termination for fetal anomalies at 8 centers with the largest known experiences worldwide.

STUDY DESIGN

Outcomes in 402 cases of selective termination in pregnancies with dizygotic twins from 8 centers in 4 countries were analyzed by year, gestational age at procedure, and indication. Reductions of fetuses were as follows: 2 to 1, n = 345; 3 to 2, 39; >/=4 to 2 or 3, n = 18. Potassium chloride was used in all procedures.

RESULTS

Selective termination resulted in delivery of a viable infant or infants in >90% of cases. Loss up to 24 weeks occurred in 7.1% of cases in which the final result was a singleton fetus and in 13.0% of cases in which the final result was twins. Loss was 6.6% as a result of structural abnormalities, 7.0% for chromosomal abnormalities, and 10% for mendelian abnormalities (difference not statistically significant). Loss rates for procedures were as follows: 9-12 weeks, 5.4%; 13-18 weeks, 8.7%; 19-24 weeks, 6.8%; and >/=25 weeks, 9.1% (difference not statistically significant). Mean gestational age at delivery was 35.7 weeks. No differences were seen in outcomes by maternal age. The rate of very early premature deliveries has fallen in recent years. There were no known cases of disseminated intravascular coagulation or serious maternal complications.

CONCLUSION

(1) Selective termination, in the most experienced hands, can be technically performed in all 3 trimesters with good outcomes in >90% of cases. (2) The previously observed increase in second- versus first-trimester losses has diminished. (3) Third-trimester procedures, where legal, can be performed with a good outcome for the surviving fetus.

Presence of RNase A causes aberrant DNA band shifts

RNase A, which is routinely added during DNA purification to reduce contaminating RNA, causes shifting of DNA bands in agarose gels. DNA band sizes on agarose gels increase as much as 10%-20% when RNase A is present. The low concentrations of RNase A typically used to purify DNA cause shifting of select DNA bands, in contrast to higher concentrations of RNase A where all band are shifted and smeared. The binding of RNase A to the DNA is specific and the degree of the shift varies; not all DNA bands are retarded, and the deviation is more pronounced in certain buffers. Other proteins, such as bovine serum albumin or proteinase K, do not induce DNA band shift, suggesting the interaction is specific. The binding of RNase A to DNA is reversible. The formation of RNase:DNA complexes may affect experiments involving DNA:protein interactions such as gel shift, footprinting and filter binding assays. Researchers performing DNA characterization from miniprep protocols should be aware that RNase may cause the apparent sizes of DNA fragments to be altered and obscure the presence of very small cloned fragments.

Parthenogenetic activation of in vitro matured bovine oocytes

Bovine germinal vesicle oocytes were collected from 2- to 4-mm follicles. Oocytes were matured in medium 199 containing 10% bovine follicular fluid, FSH, and estradiol. Matured oocytes were cocultured for 2 to 24 h with dead bovine sperm in either Tyrode's medium without albumin or with 40% follicular fluid. After removal of sperm, oocytes were cultured an additional 48 to 72 h in synthetic oviduct fluid or medium 199 containing 10% follicular fluid without hormones. Oocyte activation rates (pronucleus to 8 cells), after exposure to dead sperm for 2, 4, 6, 12, or 24 h, in protein-free Tyrode's medium before embryo culture in synthetic oviductal fluid were 11, 17, 41, and 41%. Activation rates were decreased to 3, 9, 8, 27, and 34% for these same times by the addition of estrual follicular fluid to the protein-free Tyrode's medium. Substitution of bovine serum albumin for follicular fluid in the Tyrode's medium resulted in 47% oocyte activation. Activation depended on time and composition of media, occurred with high frequency with matured bovine oocytes under common in vitro culture conditions, and decreased in the presence of bovine follicular fluid. Therefore, because cleavage is not a sufficient measure of embryo quality, parthenogenetic controls must be run.

Inhibitory effect of bovine follicular fluid on in vitro maturation of bovine oocytes

To investigate its inhibitory properties, bovine follicular fluid was collected at different stages of the estrous cycle from small, medium, and large follicles. Follicular fluids were incubated with germinal vesicle stage, bovine oocytes aspirated from small follicles. Nuclear maturation was determined at 24 h. Bovine follicular fluid inhibited the spontaneous maturation of bovine oocytes. The inhibition was reversed when follicular fluid was removed from oocyte cultures by 24 h. Follicular fluid varied in its ability to inhibit germinal vesicle breakdown according to follicle size and estrual stage. Follicular fluid from both small and medium follicles at estrus had the greatest ability to prevent germinal vesicle breakdown but became less potent postestrus. Follicular fluid from large follicles at estrus had less ability to inhibit germinal vesicle breakdown than fluid from small and medium follicles. Strong germinal vesicle breakdown inhibiting activity was present in large, probably atretic follicles at late metestrus, early diestrus, and mid diestrus. However, follicular fluid from large follicles had less germinal vesicle breakdown inhibiting activity at proestrus than follicular fluid from large follicles at late metestrus, early diestrus, and mid diestrus. This proestrual activity was similar to that in Graafian follicles at estrus.

Ergonomic deficiencies: III. Root causes and their correction

This is Part III of a three-part series that examines various aspects of ergonomic deficiencies at work. Part I examined pain at work and the association between such pain or discomfort and a poorly designed workplace or poorly structured job. Part II considered causes of ergonomic deficiencies and their identification and assessment through the use of checklists. Part III demonstrates that treating the symptoms or apparent proximate causes does not assure correction of the root causes, and suggests strategies for correcting ergonomic deficiencies.

Ergonomic deficiencies: II. Probable causes

This is Part II of a three-part series that examines various aspects of ergonomic deficiencies at work. Part I examined pain at work and the association between such pain or discomfort and a poorly designed workplace or poorly structured job. Part II considers causes of ergonomic deficiencies and their identification and assessment through the use of checklists. Part III demonstrates that treating the symptoms or apparent proximate causes does not assure correction of the root causes, and suggests strategies for correcting ergonomic deficiencies.

Ergonomic deficiencies: I. Pain at work

This is Part I of a three-part series that examines various aspects of ergonomic deficiencies at work. This paper deals with pain at work and the association between such pain or discomfort and a poorly designed workplace or poorly structured job. Neglect of ergonomic principles brings inefficiency and pain to the workplace. An ergonomically deficient workplace may not cause immediate pain, because the human body has a great capacity for adapting to a poorly designed workplace or structured job. However, in time, the compounding effect of job and/or workplace deficiencies will surpass the body's coping mechanisms, causing the inevitable: physical symptoms, emotional stress, low productivity, and poor quality of work.

Control of manual lifting hazards: III. Preemployment screening

In the control of manual lifting hazards an alternative to job redesign is preemployment screening and selection. With a screening procedure, lifting stresses can be controlled by effecting a match between job demands and human work capacity. This is predicated on the principle that jobs cannot be redesigned or changed to lower their demands. Accordingly, the hazard control strategy becomes one of selecting only those individuals with the capacity to perform the given job without excessive risk. An integrative screening program suited for physically demanding jobs is presented. Prerequisites for implementation of the program include (1) step testing at submaximal levels; (2) strength testing using three standard postures (arms, back and legs); and (3) determination of job demands expressed in terms of work output and strength requirements. The criteria for screening are based on the level of utilization of each of the principal determinants of human work capacity (energy expenditure, heart rate, and strength capability).

Control of manual lifting hazards: II. Job redesign

Job content and workplace components can be altered to assure that lifting stresses remain within the acceptable limits defined for the industrial population-at-large. The plan for redesign advocates (1) maintaining the weight handled within the recommended limits; (2) modifying the workplace to enhance postural stability and to avoid handling weights and excessive physical loading; and (3) increasing available job time by reducing frequency of lifts and/or introducing appropriate rest periods. Limits recommended by the National Institute for Occupational Safety and Health on acceptable loads are reviewed.

Optimum design of containers for manual material handling tasks

The container in manual material handling represents the point of interface between the worker and his task as well as with the surrounding environment. It is at this point that many of the well known handling hazards occur which manifest themselves in stresses and strains that are transmitted to the body via the musculo-skeletal system. If a substantial number of handling hazards is to be controlled or eliminated at the source, containers designed in accordance with principles of biomechanics and related recommendations provide a logical starting point. The container characteristics to be considered in the design process are weight (and its distribution), shape, stiffness, and availability of coupling devices. This paper presents several examples which outline and detail a number of problems associated with the design of containers involved in manual tasks. Application of basic mechanics, coupled with the use of optimization techniques, is presented as the approach for dealing with the hazards and problems of containers.