Colony housing promotes structural and functional changes during surgically induced osteoarthritis in rats.

Objective: The aim of the study was to investigate how social housing with high locomotion activity affects experimental osteoarthritis (OA) in rats. Design: Rats were housed either conventionally in type IV cages in pairs or in rat colony cages (RCC) on 4 levels interconnected by jump holes or staircase in groups of 48. OA was induced by anterior cruciate ligament transection and resection of the medial meniscus (ACLT + tMx), medial meniscal tear (MMT) or destabilization of the medial meniscus (DMM). Functional changes were characterized by continues tracking of individual activity and catwalk gait analysis. Cartilage volume and bone structure were investigated at week 20 after surgery by histology and micro-CT. Results: In the RCC, healthy rats changed cage levels 82 ± 15 times daily, reduced by 30% after ACLT + tMx (p < 0.0001). In both housing systems, the order of severity of the investigated models was ACLT + tMx > MMT > DMM in all outcome measures. Compared to Type IV, RCC housed rats developed stronger gait disturbance symptoms (ACLT + tMx; 95%CI = -15-2; p < 0.004), the cartilage volume was reduced (ACLT + tMx: 95%CI = -0.1-0.5; p < 0.0001), serum levels of the cartilage remodeling marker AGNx1 were higher (MMT; 95%CI = -53-(-6); p = 0.001), bone was denser with increased volume (ACLT + tMx; 95%CI = 0.8-7.5; p = 0.004) and joints were less flexible (ACLT + tMx; 95%CI = 3.6-14; p < 0.0001). Conclusion: Housing rats in an environment allowing increased locomotion and socialization promotes structural and functional alterations during joint instability-induced OA. This increases the assay window, improves the relevance for the human disease and enables to discriminate the models in structural and behavioral parameters.

Antibiotic treatment of zebrafish mycobacteriosis: tolerance and efficacy of treatments with tigecycline and clarithromycin.

Zebrafish (Danio rerio) are a popular model organism used in a growing number of research fields. Maintaining healthy, disease-free laboratory fish is important for the integrity of many of these studies. Mycobacteriosis is a chronic bacterial infection caused by several Mycobacterium spp. and is the second most common disease found in laboratory zebrafish. Current mycobacteriosis control measures recommend the removal of infected fish and in severe outbreaks, depopulation. These measures can be effective, but less disruptive measures should be assessed for controlling mycobacteriosis, particularly when valuable and rare lines of fish are affected. Here, the in vivo efficacy of two drug candidates, tigecycline (1 µg g-1 ) and clarithromycin (4 µg g-1 ), was tested in adult zebrafish experimentally infected with Mycobacterium chelonae. We assessed both short (14 day)- and long-term (30 day) treatments and evaluated fecundity and pathological endpoints. Fecundity and histology results show that zebrafish tolerated antibiotics. Antibiotic treatments did not significantly impact the prevalence of acid-fast granulomas; however, the severity of infections (acid-fast granuloma intensity) was significantly decreased following treatments.

Should duplex ultrasonography be performed for surveillance of femoropopliteal and femorotibial arterial prosthetic bypasses?

Duplex ultrasonography (DU) has been shown to be beneficial for surveillance of lower extremity vein bypasses. However, DU as part of surveillance program for prosthetic grafts is not widely accepted. The purpose of this report was to determine if DU could reliably detect failing prosthetic infrainguinal arterial bypasses and if there were differences in predictability between femoropopliteal (FP) and femorotibial (FT) prosthetic grafts. Between January 1992 and December 1997, 89 infrainguinal grafts in 66 patients were entered into our postoperative prosthetic graft surveillance protocol, which included clinical evaluation, segmental pressures, pulse volume recordings, and DU performed every 3 months. Patients with follow-up of less than 3 months were excluded unless the graft thrombosed. An abnormal DU considered predictive of graft failure included (1) peak systolic velocity (PSV) > 300 cms/sec at inflow or outflow arteries, in the graft or at an anastomosis (unless an adjunctive arteriovenous fistula had been performed); (2) adjacent PSV ratio > 3.0; (3) uniform PSVs < 45 cms/sec; or (4) monophasic signals throughout the graft. DU was considered to have correctly diagnosed a failing graft if a stenosis > 75% the luminal diameter of the graft, at an anastomosis, or in an inflow/outflow artery was confirmed by operative or arteriographic findings or if the graft thrombosed after an abnormal DU but before intervention. Our results support the routine use of DU as a part of a graft surveillance protocol for femorotibial, but not femoropopliteal, prosthetic grafts.

Age-specific distribution of serum prostate-specific antigen in a community-based study of African-American men.

OBJECTIVES: Previous studies have observed higher age-specific serum prostate-specific antigen (PSA) values in African-American (AA) men without prostate cancer compared to white men, leading some to recommend race-specific PSA reference ranges for the early detection of prostate cancer. The primary objective of the Flint Men's Health Study was to determine age-specific PSA reference values in a community-based sample of AA men, aged 40 to 79 years. METHODS: A probability sample of 943 AA men was selected from households in Genesee County, Michigan. Men without a prior history of prostate cancer/surgery were invited to participate in a prostate cancer screening protocol, consisting of measurement of serum total PSA, free/total PSA ratio, and digital rectal examination. Sextant biopsies were recommended, based on total PSA greater than 4.0 ng/mL and/or an abnormal digital rectal examination. RESULTS: From the sample of 943 men, 732 were eligible, 432 had blood drawn for PSA testing, and 374 completed all phases of the clinical examination. The 95th percentile PSA values were estimated to range from 2.36 ng/mL for men in the fifth decade to 5.59 ng/mL for men in the eighth decade. The 95th percentile values for age-specific PSA were comparable to those observed in a similar study of white men in Olmsted County, Minnesota. The median and 5th percentile values for free/total PSA did not vary significantly across age. CONCLUSIONS: The minor differences in PSA reference ranges between AA and white men may not be of sufficient magnitude to recommend the use of race-specific PSA reference ranges for screening.

Potential selection bias in a community-based study of PSA levels in African-American men.

The first phase of the Flint Men's Health Study (FMHS) in Michigan was a community-based epidemiologic study of prostate cancer and benign prostatic hyperplasia (BPH) in African-Americans aged 40 to 79 years. An objective of the FMHS was to determine age-specified prostate specific antigen (PSA) reference ranges in a random population sample of African-American men without clinically evident prostate cancer. The FMHS study protocol included an initial in-home epidemiologic interview followed by PSA testing and a urologic examination of eligible subjects. Since the participation rate in the PSA phase of the study was under 60%, it was important to determine whether selectivity in participation biased the FMHS results for age-specific PSA distributions. Logistic regression analyses were used to investigate selectivity in the sample of subjects who participated in the PSA testing and urologic examination. Younger men, with current urologic symptoms, and with a family history of prostate cancer were more likely to participate in the PSA testing and urologic examination. Linear regression analysis indicated that greater participation by African-American men without clinically evident prostate cancer but with obstructive or irritative lower urinary tract symptoms or a family history of prostate cancer did not bias the estimated age-specific reference ranges for total PSA concentrations and free-to-total PSA ratios.

Five-step protocol for carotid endarterectomy in the managed health care era.

BACKGROUND: We developed a protocol combining 5 cost-effective strategies to determine whether elective carotid endarterectomy (CEA) could be performed safely without adversely affecting well-established low morbidity and mortality rates and with significant hospital cost savings. METHODS: Between April 1, 1995, and December 31, 1996, 109 of 141 patients were prospectively enrolled as candidates into a 5-step CEA protocol: (1) duplex ultrasonography (DU) performed at an accredited vascular laboratory as the sole diagnostic carotid preoperative study, (2) admission the day of operation, (3) cervical block anesthesia to eliminate intraoperative electroencephalogram monitoring, (4) transfer from the recovery room after a 4-hour observation period to the vascular ward, and (5) discharge the first postoperative morning. The other 32 patients were excluded from analysis; 16 patients were treated by vascular surgeons not participating in the protocol, 9 were treated concomitantly for other medical problems, and 7 were admitted emergently. RESULTS: One patient died of carotid hemorrhage the first postoperative morning, and one had an intraoperative embolic stroke for a combined mortality-stroke rate of 1.8% (2 of 109). Of the 109 patients, 70% (76) underwent operation using DU as the sole diagnostic study, 95% (104) were admitted the day of operation, 76% (83) had cervical block anesthesia, 59% (64) were transferred to the floor the day of operation, and 83% (90) were discharged the morning after operation. None of the 109 patients were adversely affected by these 5 cost-saving strategies except potentially the patient who bled the first postoperative morning. The predicted charges of a patient treated with a perioperative protocol that many vascular surgeons currently use (preoperative arteriography, general anesthesia with intraoperative electroencephalogram monitoring, overnight intensive care unit stay, discharge on postoperative day 2) was $16,073 compared with $10,437 for a patient who completed all 5 steps of the protocol detailed above. CONCLUSIONS: On the basis of these results documenting significant cost savings and acceptably low morbidity and mortality rates, this 5-step protocol may be considered the standard for performing CEA in this era of cost containment. These results may be compared with endovascular intervention, which has recently been proposed as a less expensive technique to treat carotid disease.

Is balloon angioplasty indicated for "short" stenoses of failing vein grafts?

Previous reports have suggested "short" focal stenoses in peripheral vein grafts (PVGs), namely less than 2 cm long, can be successfully balloon dilated with good long-term patency rates. We questioned if enthusiasm for balloon angioplasty of these lesions in failing PVGs is warranted. Between August 1, 1993 and December 31, 1996, we performed balloon angioplasty of "short" stenoses in 19 PVGs in 16 patients. Bypasses included seven femoropopliteal, six femorotibial, and six popliteal-tibial or -pedal PVGs. All bypasses were originally performed for limb salvage. Single lesions were present in 13 grafts and two lesions in six grafts. Ten lesions were located at an anastomosis, 10 were located in the body of the graft, and five were peri-anastomotic. Fifteen procedures were performed percutaneously. Four angioplasties were performed using an open surgical approach because a percutaneous attempt failed in one case and three grafts were either in situ or tunneled subcutaneously making them easy to expose. Completion arteriogram documented excellent initial results in all 19 grafts. Cumulative one-year primary patency rate was 39%. The assisted primary patency rate at one year was 73%. Only five grafts remained patent 7-20 months (mean, 10 months) during follow-up without requiring further revision. One patient died with a patent graft 23 months post-balloon angioplasty. Complications included two hematomas following a percutaneous approach that required surgical repair. These results when compared to publications detailing patency following surgical revision suggest that balloon angioplasty of "short" stenoses less than 2 cm long in PVGs may be better treated by surgical revision. We reserve balloon angioplasty for "short" lesions when surgical revision is associated with inordinate difficulty such as a scarred groin wound in an obese patient.

Selective use of duplex ultrasound to replace preoperative arteriography for failing arterial vein grafts.

PURPOSE: In an effort to minimize costs and patient discomfort, we determined whether duplex ultrasound (DU) could selectively replace preoperative arteriography performed in the radiology suite to diagnose failing arterial bypass grafts (FABs) constructed of autogenous vein. METHODS: Between January 1, 1994, and December 31, 1996, we treated 106 FABs. Graft revision solely on the basis of DU was performed only if a focal stenosis was clearly identified in the graft (peak systolic velocity [PSV] > 300 cm/sec, ratio of adjacent PSVs > 3.0) or in inflow or outflow arteries (resulting in uniform graft PSVs < 45 cm/sec). Intraoperative arteriograms were frequently obtained to confirm DU findings. Preoperative arteriograms were obtained if DU revealed multiple or ill-defined stenoses, diffuse inflow or outflow arterial disease, uniformly low PSVs without an identifiable lesion, or equivocal stenosis despite clinical evidence of an FAB. RESULTS: Seventy-three (69%) FABs with 81 lesions were revised on the basis of DU only. Of 76 stenotic lesions, an intraoperative arteriogram or surgical findings confirmed a diameter stenosis of 75% to 99% in 69 grafts (91%) and stenosis of 50% to 74% in three grafts (4%). DU incorrectly identified the site of stenosis or underdiagnosed the extent of disease in four grafts (5%). DU correctly identified the site of missed arteriovenous fistulas in five grafts. The 73 FABs were treated with intraoperative balloon angioplasty (30 grafts), patch angioplasty (20), interposition or jump grafts (12), ligation of arteriovenous fistula (3), a new bypass graft (1), or a combination of these interventions (7). A significant change in intraoperative strategy potentially could have been avoided if a preoperative arteriogram had been obtained in three of the 73 FABs (4.1%). CONCLUSIONS: DU can reliably be used to revise FABs and avoid the morbidity, discomfort, and cost of confirmatory arteriography in two thirds of cases.

A two-step intervention of increase mammography among women aged 65 and older.

OBJECTIVES: This study evaluated a two-step intervention for mammography screening among older women. METHODS: Four hundred and sixty women, identified from physician practices, were randomized to a control or a two-step intervention (physician letter and peer counseling call) group. Women in the intervention group who obtained a mammogram received a grocery coupon. RESULTS: Over the 12 months of the study, more women in the intervention group than in the control group obtained mammograms (38% vs 16%). The most dramatic difference was in the higher odds that women in the intervention group would obtain a mammogram within 2 months (odds ratio = 10.5). CONCLUSIONS: The intervention significantly increased screening mammography. Future efforts must be multifaceted and incorporate the unique concerns of older women.

Girl Talk: development of an intervention for prevention of HIV/AIDS and other sexually transmitted diseases in adolescent females.

The number of adolescent females between the ages of 13 and 19 who are contracting sexually transmitted diseases (STDs) is rising at an alarming rate. Although the issue of STDs has been overshadowed by continued public debate over adolescent pregnancy and childbearing, it demands attention. Particularly concerning is the fact that STDs increase the likelihood of transmitting HIV (N.E. MacDonald et al., 1990). To offset the growing incidences of STDs among female adolescents, gender-specific interventions are needed. Following is a description of the theoretical underpinnings that informed and guided the development of a gender-specific intervention titled Girl Talk. A two-stage creation and review process was used to design this 2.5-hr, four-session intervention. An overview of the quasi-experimental design that compared a nonequivalent comparison and two intervention groups (peer led and adult led) is presented. Baseline characteristics of the three groups are reported. Also described is how participant feedback and a design content analysis are used to evaluate the appropriateness of the intervention for adolescent females.

Duplex ultrasonography to diagnose failing arterial prosthetic grafts.

BACKGROUND: Although several reports have documented the usefulness of a surveillance program with duplex ultrasonography (DU) to diagnose failing autologous vein bypasses, the effectiveness of DU to detect failing arterial prosthetic grafts has not been confirmed. We attempted to determine whether our program, which included DU and other noninvasive techniques (NonDU), was useful for this purpose. METHODS: Between July 1, 1991, and September 30, 1994, 85 prosthetic bypasses in 59 patients performed for lower extremity ischemia were entered into a graft surveillance protocol. There were 35 femoropopliteal, 16 femorotibial, 15 iliofemoral, 13 axillofemoral, and 6 femorofemoral bypasses. Both DU and NonDU were performed 1 week and every 3 months after the initial bypass or after graft revision. NonDU criteria of a failing graft included changes in symptoms or pulses, decreased ankle/brachial index greater than 0.15, or diminution of ankle pulse volume recordings greater than 50%. Normal grafts were bypasses that had less than 50% stenosis documented by arteriography or remained patent. Problem grafts were those that required revision or thrombosed before intervention. Follow-up of patient grafts ranged between 3 and 36 months (mean, 11 months). RESULTS: DU predicted 17 (81%) of 21 problem grafts versus only 5 (24%) diagnosed by NonDU (p = 0.001). Lesions associated with these 21 grafts were perianastomotic in 10 cases, in adjacent inflow or outflow arteries in 8 cases, and intrinsic to the graft in 3 cases. The likelihood of a graft thrombosing in the presence of a normal test was 7% (4 of 58) for DU compared with 21% (16 of 76) for NonDU (p = 0.04). CONCLUSIONS: DU is more sensitive than NonDU in predicting failure of prosthetic grafts. This study suggests that DU should routinely be performed as part of a surveillance program for peripheral arterial prosthetic bypasses.

Venous aneurysms: surgical indications and review of the literature.

BACKGROUND: During the last 20 years we diagnosed five cases of venous aneurysm of the jugular (n = 4) and basilic (n = 1) veins. The purpose of this report was to determine the natural history and indications for surgery of venous aneurysms. METHODS: Our five cases were included in an English-language literature review performed through August 1993. RESULTS: In our series two aneurysms (one external jugular vein, one basilic vein) were excised for cosmetic reasons. Three internal jugular vein aneurysms were followed up for up to 4 years without complications with serial color duplex ultrasonography. Of 32 patients with abdominal venous aneurysms (18 portal, seven inferior vena cava, four superior mesenteric, two splenic, one internal iliac), 13 (41%) had major complications including five deaths. Of 31 patients with deep venous aneurysms of the extremity (29 popliteal, two common femoral), 22 (71%) had deep vein thrombosis or pulmonary embolism and in 17 recurrent deep vein thrombosis or pulmonary embolism developed when patients were treated with anticoagulation alone. CONCLUSIONS: Prophylactic surgery is cautiously recommended for low-risk patients with venous aneurysms of the abdomen and strongly recommended for most patients with lower extremity deep venous aneurysms. Other venous aneurysms should be excised only if they are symptomatic, enlarging, or disfiguring.

Successful preservation of an infected common femoral vein to common femoral vein crossover prosthetic graft.

We used selective graft preservation to treat an infected anastomosis of a functioning common femoral vein to common femoral vein crossover PTFE bypass performed for iliac vein occlusion. The graft was successfully salvaged by operative debridement and placement of a rectus abdominis muscle flap. With the growing interest in venous reconstructive surgery, bypass infections may be seen more frequently. This case illustrates that selective preservation of infected prosthetic grafts anastomosed to a peripheral vein may be a simple and improved method to treat these complications.

Deep femoral artery pseudoaneurysm caused by acute trunk and hip torsion.

Spontaneous pseudoaneurysm is extremely uncommon. Apparently the first case of a deep femoral artery pseudoaneurysm, caused by acute trunk and hip torsion during a golf swing, is reported. The lesion was documented by computed tomography, arteriography and surgical investigation. The present report is aimed at making known the possibility of such a complication following this and similar types of physical activity in order to enable prompt assessment and treatment of the lesion.

Evaluation of the p-nitro-alpha-acetylamino-beta-hydroxypropiophenone differential test for identification of Mycobacterium tuberculosis complex.

The p-nitro-alpha-acetylamino-beta-hydroxypropiophenone (NAP) differential test for the identification of Mycobacterium tuberculosis recovered from clinical specimens was evaluated by two laboratories and found to be a rapid and accurate procedure with a specificity exceeding 99%.