Shouldered plates and shats in tension and torsion

Room-temperature and frozen-stress photoelastic tests have been carried out to determine the magnitude, position, and extent of the stress concentrations which occur in the blending radii at the junctions of sections of different widths in symmetrical plates subjected to direct loads.

An empirical equation has been derived from the flat-plate tests which is also applicable to shafts in tension.

Other published data are consisent with the predictions of the empirical equations.

Stress concentration factors for shafts in torsion are lower than in tension.

A randomized trial comparing the efficacy of four treatment regimens for uncomplicated falciparum malaria in Assam state, India

A four-arm drug sensitivity study compared chloroquine, sulfadoxine-pyrimethamine (SP), mefloquine and mefloquine-artesunate in Sonitpur and Karbi Anglong districts in Assam state, India. Two criteria were used to ascertain outcome: success of clinical treatment and parasitologic cure. In Sonitpur, at 14 days, there were 36/56 early and late treatment failures plus late parasitologic failures to chloroquine and 16/56 for SP. In Karbi Anglong, combined treatment failure at 14 days was 16/56 to chloroquine and 8/60 to SP. Mefloquine and mefloquine-artesunate demonstrated 93.9% and 93.6% sustained responses respectively at 42 days. High failure rates to both chloroquine and SP preclude the use of these drugs as first-line treatment for uncomplicated falciparum malaria in this region. A mefloquine-artesunate combination presents an effective alternative utilizing the currently recommended higher dose of mefloquine.

A prospective, pilot study of early corticosteroid cessation in high-immunologic-risk patients: the Cincinnati experience

BACKGROUND

The first prospective trial of steroid withdrawal dedicated to high-immunologic-risk patients is reported herein.

METHODS

Twenty-five patients were enrolled prospectively in an IRB-approved HIPAA-compliant protocol. Immunosuppression included corticosteroid withdrawal (CSWD) at 7 days, tacrolimus (target trough level 4 to 8 ng/mL), sirolimus (target trough level 8 to 12 ng/mL), and Mycophenolate Mofetil (2 g/d). Induction with daclizumab (2 mg/kg) on posttransplant days (PTD) 0 and 14 was administered to the first 10 patients. The protocol for the next 15 patients was modified because of high acute rejection rates to include received T-cell-depleting antibody induction therapy with thymoglobulin (1.5 mg/kg) on PTDs 0 and 2 followed by daclizumab on Postoperative day (POD) 14. Recipient inclusion criteria included: (1) repeat transplant recipients; or (2) patients with a peak PRA > or =25%. All rejection episodes were diagnosed by biopsy and graded using Banff '97 criteria.

RESULTS

Twenty-five patients were enrolled and median follow-up was 402 days. Forty percent of recipients were black, 68% of patients were repeat transplant recipients, 68% received deceased donor kidneys, and 36% had a peak flow PRA >25%. Overall acute rejection, graft survival, and patient survival rates of 40%, 88%, and 96%, respectively, were observed for the duration of the study. Acute rejection occurred in 6 of 10 patients (60%) with daclizumab induction; however, acute rejection rates fell to 27% when thymoglobulin was introduced (P = .1).

CONCLUSIONS

This study supports our previous observations in a multivariate analysis of early CSWD patients, wherein polyclonal antibody induction therapy reduced acute rejection. High-immunologic-risk patients may be able to undergo early CSWD with acceptable rates of acute rejection.

Corticosteroid avoidance ameliorates lymphocele formation and wound healing complications associated with sirolimus therapy

INTRODUCTION

Sirolimus (RAPA) and corticosteroids (CS) both inhibit wound healing. To evaluate the possibility that RAPA and CS have additive effects on wound healing, we evaluated the effects of corticosteroid avoidance (CSAV) on wound healing complications in patients treated with RAPA.

METHODS

One hundred nine patients treated with a CSAV regimen (no pretransplantation or posttransplantation CS) were compared with a historical control group (n = 72) that received cyclosporine (CsA), mycophenolate mofetil (MMF), and CS. The CSAV group received low-dose CsA, MMF, RAPA, and thymoglobulin induction. Complications were classified as follows: wound healing complications (WHC) or infectious wound complications (IWC). WHC included lymphocele, hernia, dehiscence, diastasis, and skin edge separation. IWC included wound abscess and empiric antibiotic therapy for wound erythema.

RESULTS

The CSAV group was largely CS-free: 11% of patients received CS for rejection, 12% of patients received CS for recurrent disease, and 85% of patients are currently off CS. The CSAV group had a significantly lower incidence of WHC (13.7% vs 28%; P = .03) and lymphoceles (5.5% vs 16%; P = .02) than the control group. There was no difference in the incidence of IWC between the 2 groups. Patients who received CSAV were 18% less likely (P = .57) to develop any type of complication, 41% less likely (P = .20) to develop a WHC, and 71% less likely (P = .018) to develop a lymphocele.

CONCLUSIONS

CSAV in a RAPA-based regimen results in a marked reduction in WHC and lymphoceles. Therefore, CSAV provides a promising approach for addressing WHC associated with RAPA therapy.

Body Weight Alterations Under Early Corticosteroid Withdrawal and Chronic Corticosteroid Therapy With Modern Immunosuppression

Weight gain is a well-known complication of corticosteroid maintenance therapy. The purpose of our study was to compare patterns of weight gain under chronic corticosteroid therapy (CCST) to those observed under early corticosteroid withdrawal (CSWD) in renal transplant recipients.

METHODS

Renal transplant recipients who underwent early CSWD in IRB-approved prospective trials were compared to a historical control group of patients receiving CCST who were matched for age, sex, and race.

RESULTS

One hundred sixty-nine patients with early CSWD were compared to 132 patients who received CCST. Mean population weight gain was significantly higher in CCST patients at 12 months (5.52 kg vs 3.05 kg, P < .05) posttransplant. Caucasian CSWD patients demonstrated a greater reduction in weight gain with CSWD than African Americans (mean weight decrease 2.9 vs 1.9 kg/patient, P < .05). Patients who were overweight (body mass index [BMI] 25-30) or obese (BMI > 30) demonstrated a greater reduction in weight gain with CSWD at 1 year (mean reduction in weight gain with CSWD 5.3 kg/patient and 4.4 kg/patient) than did patients of normal weight (BMI < 25; 0.1 kg/patient, P < .01 and <.05 versus BMI < 25).

CONCLUSIONS

Early CSWD patients gain significantly less weight than CCST patients following transplantation. Marked variations in the effect of early CSWD on weight gain may be observed due to race and pretransplant BMI. Caucasians and overweight patients demonstrate greater benefits from CSWD than African Americans and patients with normal BMI.

Global Cardiovascular Risk Under Early Corticosteroid Cessation Decreases Progressively in the First Year Following Renal Transplantation

A primary reason to eliminate corticosteroids from immunosuppressive regimens in solid organ transplant recipients is improved cardiovascular risk profiles. Although a number of studies have documented that corticosteroid withdrawal (CSWD) regimens reduce hypertension, hyperlipidemia, diabetes, and weight gain, global assessments of cardiovascular risk under CSWD have not been reported. The purpose of this study was to document cardiovascular risk under CSWD using a global risk assessment by Framingham risk assessment.

METHODS

Framingham global cardiovascular risk assessments were performed at baseline and 3, 6, and 12 months posttransplant on patients enrolled in prospective, IRB-approved early (<7 days of corticosteroids) CSWD trials. Framingham score was based on age, sex, presence of diabetes, HDL and total cholesterol, and systolic blood pressure. All patients were nonsmokers. Left ventricular hypertrophy assessment by EKG criteria was not available at all time points and therefore were not included.

RESULTS

One hundred eighty-three patients were included in the analysis. Fourteen percent of patients had evidence of coronary heart disease (prior MI, CABG, PTCA, or significant cardiovascular disease as evidenced by angiography) prior to transplant. Complete information was available for 160 patients at baseline, 132 at 1, 3, and 6 months, and 93 at 12 months posttransplant. Mean 10-year risk (expressed as percent) for developing coronary heart disease decreased over time: 8.03 at baseline, 8.31 at 3 months, 7.40 at 6 months, and 7.20 at 12 months, indicating that global cardiovascular risk fell at 1 year posttransplant by about 10% in renal transplant recipients undergoing early CSWD.

CONCLUSIONS

Estimation of cardiovascular risk by Framingham risk factor assessment allows incorporation of several cardiovascular risk factors into a single estimate, thereby accounting for differential effects of each individual factor on global cardiovascular risk. This experience indicates that global cardiovascular risk decreases by approximately 10% at 1 year posttransplant in renal transplant recipients who undergo early corticosteroid withdrawal (CSWD).

African American Renal Transplant Recipients Benefit From Early Corticosteroid Withdrawal Under Modern Immunosuppression

African Americans have historically been considered high-risk renal transplant recipients due to increased rejection rates and reduced long-term graft survival. Modern immunosuppression has reduced rejections and improved graft survival in African Americans and may allow successful corticosteroid withdrawal. Outcomes in 56 African Americans were compared to 56 non-African Americans enrolled in early withdrawal protocols. Results are reported as African American versus non-African American. Acute rejection at 1 year was 23% and 18% (P = NS), while patient and graft survival was 96% versus 98% and 91% versus 91% (P = NS), respectively. In conclusion, early withdrawal in African Americans is associated with acceptable rejection rates and excellent patient and graft survival, indicating that the risks and benefits of early withdrawal are similar between African Americans and non-African Americans. Additional followup is needed to determine long-term renal function, graft survival, and cardiovascular risk in African Americans with early steroid withdrawal.

Nonmetro elders better off than metro elders on some measures, not on others

The author examines characteristics of the nonmetropolitan elderly in the United States. "A larger share of the nonmetro population was age 60 and older (18 percent) in 1996 than the metro population (15 percent). At ages 75 and older, half of all elderly persons are living alone. This is associated with a greater likelihood of being poor: 42 percent of nonmetro persons age 75 and older were poor or near-poor, compared with 28 percent of their metro counterparts."

Morphologic effects of fast neutrons or photons on the canine kidney

Thirty-nine adult male Beagles received either fast neutron or photon irradiation to the right thorax to determine the relative biological effectiveness of fast neutrons on normal pulmonary tissue. The right anterior abdomen, including the cranial half of the right kidney, was included in the field of irradiation. Twenty-four dogs (six/group) received fast neutrons with an average energy of 15 MeV to total doses of 1000, 1500, 2250, or 3375 cGy in four fractions per week for 6 weeks. Fifteen dogs received 3000, 4500, or 6750 cGy of photons (five/group) in an identical fractionation pattern. All 12 neutron irradiated dogs receiving 3375 and 2250 cGy and 1 of 6 receiving 1500 cGy, developed clinical and clinical pathologic signs of hepatic, pancreatic, and gastrointestinal disturbances, but no signs of renal injury were seen. These 13 dogs died or were euthanatized 47-367 days after irradiation. Only 1 of 5 dogs receiving 6750 cGy of photons developed similar signs and died 708 days post-irradiation. The remaining 11 neutron irradiated dogs and 14 photon irradiated dogs eventually died of other causes. All 39 dogs were necropsied and their kidneys were compared to each other and to control dogs. Radiation induced lesions included hemorrhages, necrosis and disappearance of tubular epithelia, glomerulosclerosis, atrophy and fibrosis. These lesions were associated with degenerative and occlusive vascular changes and were much more severe in the neutron irradiated dogs. The relative biologic effectiveness of fast neutrons for canine kidney assessed by gross and microscopic pathology is approximately 4.5 (6750/1500).

Does Electricity Speed Healing of Nonunion Fractures?

Traditionally, surgeons have performed bone-graft surgery on athletes (and others) with traumatic nonunion fractures; nowadays, they may be likely to prescribe electric bone-growth stimulators. But physicians have yet to agree on the usefulness of those devices.

CT-assisted assessment of bladder and rectum dose in gynecological implants

Eight patients who received gynecological implants with Fletcher-Suit type applicators were involved in this study. An orthogonal pair of films and computed tomographic scans were obtained for each patient. In the CT study, judicious use of contrast materials and selective window and level settings permitted clear delineation of the bladder and the rectum boundaries relative to the implanted applicators. In comparison to reference organ doses derived from the orthogonal film pair method, the maximum organ doses estimated from the CT-assisted evaluation were considerably higher, by approximately twofold on the average. The differences between the values estimated from the two methods vary from patient to patient, being highly dependent on the individual anatomy and the geometry of the implanted sources. These preliminary results point to the inaccuracy of the conventional method of estimating organ doses. CT-assisted evaluation may be necessary to accurately calculate organ doses in gynecological applications.

Paraaortic lymph node irradiation in cervical carcinoma without prior lymphadenectomy

A study of complications associated with paraaortic irradiation was undertaken in patients with uterine cervical cancer who had not undergone prior lymphadenectomy. Between 1975 and 1984, 29 highly selected patients received paraaortic irradiation as part of their definitive treatment for cervical carcinoma. Paraaortic fields were irradiated to a total dose of 4,200-5,000 rad (42-50 Gy), in fractions of 150-180 rad (1.5-1.8 Gy). An anteroposterior-posteroanterior technique was generally used. All fields were treated every day. There were no instances of small-bowel obstruction or other major complications, surgical procedures, or deaths caused by paraaortic irradiation. Eleven patients (38%) have no evidence of recurrent disease 23-120 months after completion of therapy. Paraaortic irradiation was well tolerated in this patient group without prior staging lymphadenectomy. Thus, in selected patients and with appropriate techniques, paraaortic irradiation for cervical carcinoma may be used with relative safety.

Upper Body Exercise: 'Jarming' Instead of Jogging

Once-enthusiastic joggers unlace their running shoes. Entrepreneurs promote armchair exercise. Epidemiologists advocate mild exercise. What do these trends have in common? They may be tied to a trend toward upper body exercise.

Judo: A Sport Fit for Everybody?

After a century-long tradition as an Eastern sport, judo has begun to attract some nontraditional Western fitness buffs. The reason: Judo may offer certain fitness benefits and present a low risk of serious injury compared with other contact sports.

On the Rebound: A Fitness Love Affair

Rebounders-the minitrampolines used for jogging or exercise routines-have sparked mixed feelings. Some exercise enthusiasts love them, many researchers don't. It is the story of a fitness fad trying to achieve respectability.

Of Magic, Miracles, and Exercise Myths

Exercise physiologist James S. Skinner, PhD, scrutinizes some popular exercise myths end speculates about why they endure. His comments are enlightening, entertaining, and even a bit philosophical.

Does Sports Medicine Fit in the New Health Care Market?

Physicians are being forced to compete for their share of a changing health care market. Two traditional concerns of sports medicine-fitness and preventive care-may help some physicians keep their practice healthy.

Out-of-wedlock births, premarital pregnancies and their effect on family formation and dissolution

The persistent rise in the proportion of firstborn babies conceived out of wedlock, which characterized the period from the 1950s to the early 1970s, has apparently abated, according to data analyzed from the June 1980 and June 1982 Current Population Surveys (CPS). Although the proportion increased from 16 percent of firstborn children among women 15 years and older in the 1950-1954 period to 34 percent in the 1970-1974 period, it subsequently declined to 31 percent in 1975-1979, and has remained at that level. Since 1970, approximately 68 percent of firstborn children among teenage women have been conceived outside of marriage, four times the level recorded during the same period among women aged 20 and older. In addition, more than 90 percent of firstborn babies among black teenagers have been conceived out of wedlock, compared with about 60 percent among white teenagers. Among women aged 20 and older, about 50 percent of firstborn babies of black mothers and approximately 13 percent of firstborn babies of white mothers have been conceived outside of marriage. Despite the recent overall stability in the proportion of first babies conceived out of wedlock, a notable decline has occurred in the likelihood of mothers to marry before the birth of the child. Between the 1950-1954 and the 1970-1974 periods, about 50 percent of all women who had an out-of-wedlock pregnancy married before the birth; this proportion has since fallen below 40 percent.(ABSTRACT TRUNCATED AT 250 WORDS)

Pathologic effects of fractionated fast neutrons or photons on the pancreas, pylorus and duodenum of dogs

Thirty-nine adult male Beagles received either fast neutron or photon irradiation to the right thorax to determine the relative biological effectiveness (RBE) of fast neutrons on normal pulmonary tissue. The right anterior abdomen was included in the field of radiation. Twenty-four dogs (six/group) received fast neutrons with an average energy of 15 MeV to total doses of 1000, 1500, 2250 or 3375 rad in four fractions per week for six weeks. Fifteen dogs received 3000, 4500 or 6750 rad of photons (five/group) in an identical fractionation pattern. All neutron irradiated dogs receiving 3375 and 2250 rad and one receiving 1500 rad developed clinical signs of pancreatic, hepatic and gastrointestinal disturbances. The liver enzymes of these dogs became elevated and they died or were euthanatized in extremis 47-367 days after irradiation. Only one 6750 rad photon dog developed similar signs and died 708 days post-irradiation. Five neutron and 10 photon exposed dogs died of other causes. Neutron-induced lesions in the stomach and duodenum included hemorrhages, erosions, ulcerations and fibrosis. Ulcers perforated the GI tract of five dogs. Pancreatic lesions included degranulation and necrosis of acinar cells, fibrosis ans atrophy. Islet cells were not obviously damaged. All lesions were associated with degenerative and occlusive vascular changes. The RBE of fast neutrons, assessed by clinical signs, gross and microscopic pathology, is approximately 3-4.5 for pancreas and about 4.5 for pylorus and duodenum.

Assessing cohort birth expectations data from the Current Population Survey, 1971-1981

Data from the fertility supplements to the Current Population Survey from 1971 to 1981 indicate that in the aggregate, the lifetime birth expectations of married women 18 to 39 years old in 1971 will closely approximate their completed cohort fertility. During this period, the youngest group of women, 18 to 24 years old, delayed their childbearing; their short-term expectations (1971-76) were not realized, but they made up enough births in the latter half of the decade to enable them to attain their lifetime birth expectations. In retrospect, the "failure" of birth expectations data to predict the "period" fertility downswing in the 1970s resulted not from poor predictions of married women, but rather from unanticipated marital and subsequent childbearing patterns of women who were single at the beginning of the decade. The authors conclude that birth expectations are useful predictors of completed cohort fertility, if adjustments are made to incorporate changes in the proportions married within the birth cohort.

RTOG Phase I study on fast neutron teletherapy for squamous cell carcinoma of the esophagus

From August, 1977, through January, 1981, the Radiation Therapy Oncology Group sponsored a Phase I study (RTOG 77-09) on the use of fast neutrons for treating inoperable squamous cell carcinomas of the esophagus. A total of 39 evaluable patients were treated with curative intent using either fast neutrons alone or in combination with low LET irradiation as part of a mixed beam fractionation scheme. Actuarial survival curves are presented for both the "neutrons alone" and the "mixed beam" treatment groups. There was no significant survival difference between these groups of patients. The projected survival at two years is less than 10%, which is comparable with megavoltage photon results for an unselected series of patients. The size of the primary lesion and the initial Karnofsky performance status were found to be the most important prognostic indications for prolonged survival. Sixteen of 39 patients were felt to have achieved local clearance of their tumor at some time during their follow-up with the median time until a local recurrence being 17 months. Treatment related complications and patterns of metastatic spread are discussed. In general, it appeared that the response of large tumors to neutron irradiation resulted in necrosis and fistula formation. In many cases this was accompanied by persistent/recurrent tumor within the high dose radiation volume.

Neoplasia in fast neutron-irradiated beagles

One hundred fifty-one beagle dogs were irradiated with either photons or fast neutrons (15 MeV) to one of three dose-limiting normal tissues--spinal cord, lung, or brain. The radiation was given in four fractions per week for 5 weeks (spinal cord), 6 weeks (lung), or 7 weeks (brain) to total doses encompassing those given clinically for cancer management. To date, no nonirradiated dogs or photon-irradiated dogs have developed any neoplasms. Seven dogs receiving fast neutrons have developed 9 neoplasms within the irradiated field. Of the neutron-irradiated dogs at risk, the incidence of neoplasia was 15%. The latent period for radiation-induced cancers has varied from 1 to 4 1/2 years at this time in the study.

Treatment experience: locally advanced sarcomas with 15 MeV fast neutrons

Experience with ten evaluable osseous sarcomas and ten evaluable advanced soft tissue sarcomas treated with neutrons of a mean neutron energy of 15 MeV are described. Neutron irradiation with or without conventional megavoltage radiotherapy is an effective modality in the treatment of these patients. No correlation between response rate and grade or whether fast neutrons alone or combined with megavoltage radiotherapy was noted. Those patients receiving a neutron dose of 2195 neutron plus gamma rads or greater all had a complete response.