Anesthesia for endovascular repair of abdominal and thoracic aortic aneurysms: a review article

Open repair of abdominal aortic aneurysms (AAA) and thoracic aortic aneurysms (TAA) are associated with significant morbidity and mortality. Endovascular aortic aneurysm repair (EVAAR) using a stent graft is a new alternative to traditional open repair. There are various types of anesthesia which can be utilized for EVAAR; specifically general endotracheal anesthesia, regional anesthesia, and monitored anesthesia care (MAC) with local anesthetic infiltrated at the incision site. Choice of anesthetic technique may be dependent upon a patient's co-existing diseases. We have prepared a review article discussing the various types of anesthesia available for this procedure, including the specifics of each technique and pros and cons of each option. The most often utilized technique appears to be general anesthesia, often times related to surgeon unfamiliarity with the EVAAR procedure. Regional techniques, including continuous epidural or continuous spinal anesthesia are utilized in some cases with very good results. This technique can provide more hemodynamic stability and better pain control than general alternative, MAC with local, is an extremely safe and effective technique for the EVAAR procedure, especially in patients with severe co-existing diseases. In addition, this technique also minimalizes sedation and post-operative analgesic requirements, decreases cardiopulmonary complications, and decreases overall hospital stay, thereby reducing cost.

Choosing identity-release sperm donors: the parents' perspective 13-18 years later

BACKGROUND

A growing number of donor insemination (DI) programmes offer 'open-identity' sperm donors, who are willing to have their identity released to adult offspring. We report findings from parents who chose such donors and whose children are now adolescents.

METHODS

Using mail-back questionnaires, parents from 45 households (40% headed by lesbian couples, 38% by single women, 22% by heterosexual couples) reported their experience with using an open-identity donor and disclosure about it, as well as their child's plans for donor identity-release(sm).

RESULTS

Almost no parents regretted using an open-identity donor. Almost all parents had told their child about his or her DI conception early on and reported a neutral to moderately positive impact. Finally, of those who had told, almost all expected their child to obtain the donor's identity. We also discuss differences found between birth mothers and co-parents and among single women, lesbian couples, and heterosexual couples.

CONCLUSIONS

Families were relatively open and positive about their use of DI and that their child could obtain the donor's identity. Disclosure did not appear to have a negative impact on the families, regardless of parental sexual orientation and relationship status.

Chest radiographic appearances in severely burned adults. A comparison of early radiographic and extravascular lung thermal volume changes

Chest radiographs (CXRs) have previously been used as a diagnostic tool to detect changes in lung water. In this study CXR changes in severely burned adults, in the absence of an inhalation injury, preceded detectable increases in extravascular lung thermal volume (ELTV) by 3 to 5 days. The hypothesis that early CXR density changes in burned patients have an infectious cause, not related to changes in ELTV, was tested. Blood cultures, CXRs, and ELTV were evaluated during the first 15 days after injury in severely burned adults who had no identified inhalation injury. Chest radiographs were scored daily on a 1 to 5 scale, with 1 = normal, 2 = peribronchial cuffing, 3 = mild interstitial infiltrates, 4 = severe interstitial infiltrates, and 5 = alveolar infiltrates. In all patients, except those who were septic, increases in their CXR density scores correlated well with increases in ELTV. The ELTV/CXR score ratios for septic burn patients on days 1 to 6 postburn was 1.7 +/- 0.2 compared with 4.2 +/- 0.4, (means +/- SEM) for nonseptic (P < .001), whereas the ELTV/CXR score ratios for septic and nonseptic patients, 7 to 15 days postburn, were 3.8 +/- 0.4 and 3.4 +/- 0.5, respectively. We suggest that before any measurable change in ELTV early increases in CXR density scores in burned patients without a concomitant inhalation injury are caused by intraalveolar pneumonitis or hyaline membrane atelectasis and not increased ELTV.

Primary lymphoma of the liver: a case report and review

The case of a previously healthy man who developed primary non-Hodgkin's lymphoma of the liver is presented. Biopsy confirmed that the tumour was of the diffuse large cell type and was of apparent T-cell origin. The diagnosis of these rare tumours is suggested by the presence of a hepatic mass without lymphadenopathy, splenomegaly or bone marrow involvement, as well as normal carcinoembryonic antigen and alpha-fetoprotein levels. However, histological examination of tissue is essential to confirm the diagnosis. The response to treatment varies, but surgical resection and/or chemotherapy can result in prolonged remissions. The literature on this topic is briefly reviewed.

Inclusion of older women in randomized clinical trials: factors associated with taking study medication in the fracture intervention trial

OBJECTIVES

The purpose of this study is to describe the early study medication discontinuation (SMD) experience during the first year of follow-up in a randomized clinical trial in older women and to determine the associations between various baseline characteristics and risk of SMD. DESIGH, SETTING, AND PARTICIPANTS: The authors studied 6,459 postmenopausal women aged 55 to 80 from 11 clinical settings during their first year of participation in the Fracture Intervention Trial (FIT). This trial was designed to test the efficacy of alendronate (Fosamax) on fracture prevention among women with low bone mass.

RESULTS

Study medication discontinuation was greatest in the first month post-randomization (2.2%) and declined thereafter. Cumulative rates of study medication discontinuation were 4.8% (n = 311) at 3 months and 11.1% (n = 717) at 12 months. SMD was not associated with age, marital status, alcohol consumption, regular exercise, past estrogen replacement therapy use, bone mineral density, or personal or maternal fracture history. After adjusting for covariates and markers of comorbidity, the strongest predictor of SMD was fair-to-poor self-rated health (relative risk (RR) 2.10; 95% confidence interval (CI) 1.47, 2.99). Having four or more depressive symptoms was also a significant predictor and had a risk associated with SMD (RR vs none 1.34; 95% CI 1.05, 1.71) similar to that seen for individuals with good self-rated health (RR 1.49; 95% CI 1.16, 1.91).

CONCLUSIONS

Results from this cohort emphasize that clinical trials in older women with multiple concomitant conditions can achieve high levels of adherence. Thought should be given to measuring self-rated health and depressive symptoms before randomization to help identify individuals to be targeted for special assistance programs that focus on encouraging adherence.

Infant sleep position practices 2 years into the "back to sleep" campaign

Since the 1992 American Academy of Pediatrics (AAP) recommendation to put babies to sleep in the nonprone position and the subsequent 1994 "Back to Sleep" campaign, the U.S. rate of sudden infant death syndrome (SIDS) has decreased more than 40%. This study reports sleep position practices in the greater Philadelphia area during 1996 and 1997. Four hundred and ten parents of infants 6 months of age or less answered a questionnaire by interview in Philadelphia clinics and private pediatric offices from December 1995 through February 1997. Sleep position practices and other SIDS risk factors were measured among demographic groups and compared with reported rates in a similar population from 1993 and 1994. Data were analyzed by Chi square after analysis of correlation coefficients. Significance is reported at p < 0.05. Seventy-two percent of all infants surveyed slept nonprone (NP) compared to 31.8% in 1993 and 59.1% in 1994. The population was 61% African-American (AA), 62% clinic patients. The breast feeding rate was 31%, maternal smoking 17%, and cosleeping 46%. AA infants (67% vs. 82%), infants receiving care at a clinic (66% vs. 84%), and infants > 3 months old (65% vs. 76%) are less likely to be placed nonprone. Most parents who place infants on their back report it was recommended by a medical professional (56%). The majority of those placing infants prone do so because their infant is more comfortable or sleeps better (65%), although 73% said their physician/nurse discussed sleep position with them. Nonprone sleeping continues to increase since the initiation of the "Back to Sleep" campaign. Disparity between some demographic groups persists. An excessive number of African-American families and clinic families still choose a prone sleep position. Many who do so cite increased infant comfort, despite knowledge of the AAP recommendation.

Detection of hypoxia in human squamous cell carcinoma by EF5 binding

Localization and quantitation of 2-nitroimidazole drug binding in low pO2 tumors is a technique that can allow the assessment of hypoxia as a predictive assay. EF5 [2-(2-nitro-1H-imidazol-1-yl)-N-(2,2,3,3,3-pentafluoropropyl) acetamide] is such a drug, and it has been shown to be predictive of radiation response in rodent tumors. Using fluorescence immunohistochemical techniques, we provide data on the presence, distribution, and levels of EF5 binding as a surrogate for hypoxia in human head and neck and uterine cervix squamous cell cancers (SCCs). Six patients with SCC were studied. Four patients had head and neck tumors, and two had uterine cervix cancers. The incubation of fresh tissue cubes in EF3 under hypoxic conditions ("reference binding") demonstrated that all tumors were capable of binding drug, and that this binding varied by a factor of 2.9-fold (174.5-516.1) on an absolute fluorescence scale. In the five patients treated at the lowest drug doses (9 mg/kg), in situ binding was quantitatable. For all six patients, the maximum rate of in situ binding varied by a factor of 6.7 between the lowest and highest binding tumor (24.8-160.3) on an absolute fluorescence scale. In tumors with high binding regions, intratumoral heterogeneity was large, extending from minimal fluorescence (<1%) up to 88.6% of reference binding. In tumors with minimal binding, there was little intratumoral heterogeneity. These studies demonstrate substantial heterogeneity of in situ binding between and within individual squamous cell tumors.

Transport of thiamine in human intestine: mechanism and regulation in intestinal epithelial cell model Caco-2

The present study examined the intestinal uptake of thiamine (vitamin B(1)) using the human-derived intestinal epithelial cells Caco-2 as an in vitro model system. Thiamine uptake was found to be 1) temperature and energy dependent and occurred with minimal metabolic alteration; 2) pH sensitive; 3) Na(+) independent; 4) saturable as a function of concentration with an apparent Michaelis-Menten constant of 3.18 +/- 0.56 microM and maximal velocity of 13.37 +/- 0.94 pmol. mg protein(-1). 3 min(-1); 5) inhibited by the thiamine structural analogs amprolium and oxythiamine, but not by unrelated organic cations tetraethylammonium, N-methylnicotinamide, and choline; and 6) inhibited in a competitive manner by amiloride with an inhibition constant of 0.2 mM. The role of specific protein kinase-mediated pathways in the regulation of thiamine uptake by Caco-2 cells was also examined using specific modulators of these pathways. The results showed possible involvement of a Ca(2+)/calmodulin (CaM)-mediated pathway in the regulation of thiamine uptake. No role for protein kinase C- and protein tyrosine kinase-mediated pathways in the regulation of thiamine uptake was evident. These results demonstrate the involvement of a carrier-mediated system for thiamine uptake by Caco-2 intestinal epithelial cells. This system is Na(+) independent and is different from the transport systems of organic cations. Furthermore, a CaM-mediated pathway appears to play a role in regulating thiamine uptake in these cells.

Chronic pain in the dental patient

This article reviews the pathophysiology and mediators of pain, and addresses the different subtypes of dental pain. An overview of pharmacotherapy is presented. Contributing factors to chronic pain syndromes are reviewed. Alternative methods of pain management are discussed.

Acute lymphoblastic leukemia with multiple cytogenetic abnormalities secondary to treatment of Ewing's sarcoma

We report the case of a 22-year-old man with Ewing's sarcoma who attained a complete remission (CR) after combination radiotherapy and chemotherapy. Secondary acute lymphoblastic leukemia with multiple cytogenetic abnormalities involving chromosome 5 and 7 developed 16 years later. The patient underwent induction chemotherapy and entered a CR. Peripheral blood stem cell transplantation from a matched sibling was performed successfully and he is in complete remission of both ALL and Ewing's sarcoma.

Time course of word identification and semantic integration in spoken language

The minimum duration signal necessary to identify a set of spoken words was established by the gating technique; most words could be identified before their acoustic offset. Gated words were used as congruous and incongruous sentence completions, and isolation points established in the gating experiment were compared with the time course of semantic integration evident in event-related brain potentials. Differential N400 responses to contextually appropriate and inappropriate words were observed about 200 ms before the isolation point. Semantic processing was evident before the acoustic signal was sufficient to identify the words uniquely. Results indicate that semantic integration can begin to operate with only partial, incomplete information about word identity. Influences of semantic constraint, word frequency, and rate of presentation are described.

Assessment of infant cardiopulmonary resuscitation rescue breathing technique: relationship of infant and caregiver facial measurements

OBJECTIVE

Although a few infants ever require resuscitation, pediatric cardiopulmonary resuscitation (CPR) is performed most commonly under 1 year of age. American Heart Association guidelines for pediatric basic life support recommend that the caregiver place his/her mouth over the infant's mouth and nose to create a seal. The way CPR is currently taught encourages parents to attempt to seal the nose and open the mouth of the infant for rescue breathing. Recent studies suggest some parents may have trouble sealing an infant's nose and open mouth, but their study participant numbers were small. The aim of this report is to estimate, among a large cohort, the ability of caregivers to create a seal to their infants for the provision of rescue breathing according to current guidelines.

METHODS

Infants up to 1 year of age (n = 281) and their caregivers were enrolled from Philadelphia pediatric offices. Facial measurements of the infants were obtained to estimate the length needed to seal the nose and open mouth, and the nose and closed mouth. Mouth widths of the caregivers were compared with their infant's nose and mouth lengths. One-way analysis of variance with Tukey's postmortem analysis and ordinary least squares means regression were used for univariate analysis with analysis of covariance used to control for the effects of multiple variables when necessary. Infant measurements were stratified into 3-month age quadrants to compare against matched adult caregiver measurements.

RESULTS

Most caregivers (n = 270) were female. Females had smaller mouth widths than males (4.9 +/- 0.5 cm vs 5.2 +/- 0.5 cm). Infant nose and mouth length increased during the first year of life, with the largest increase between 0 to 3 months and 3 to 6 months (4.2 +/- 0.4 cm to 4.7 +/- 0.4 cm). As infant age and face length increased, a progressively higher rate of adult females were estimated not to be able to cover their infant's nose and open mouth, with the greatest increase again between 0 to 3 months (9%) and 3 to 6 months (40%). All female caregivers except 1 were predicted to be able to seal their infant's nose and closed mouth by our measurements.

CONCLUSIONS

Infant face length grows rapidly during the first year of life with the most rapid growth occurring during the first 6 months. As early as 3 to 6 months of infant age, many adult caregivers' facial measurements, especially female, predict that they may not be able to form a seal for mouth-to-nose and open-mouth infant rescue breathing. By related measurements, nearly 100% of caregivers should be able to seal their infant's nose and closed mouth. If facial measurement predictions correlate with functional inability to seal an infant's nose and open mouth, infant CPR rescue breathing instruction will need to emphasize head position and creation of a seal over the mouth and nose without teaching that the mouth be open. pediatric basic life support, infant CPR, rescue breathing, sudden infant death syndrome, acute life-threatening episode.

Biotin uptake by human colonic epithelial NCM460 cells: a carrier-mediated process shared with pantothenic acid

Previous studies showed that the normal microflora of the large intestine synthesizes biotin and that the colon is capable of absorbing intraluminally introduced free biotin. Nothing, however, is known about the mechanism of biotin absorption in the large intestine and its regulation. To address these issues, we used the human-derived, nontransformed colonic epithelial cell line NCM460. The initial rate of biotin uptake was found to be 1) temperature and energy dependent, 2) Na+ dependent (coupling ratio of 1:1), 3) saturable as a function of concentration [apparent Michaelis constant (Km) of 19.7 microM], 4) inhibited by structural analogs with a free carboxyl group at the valeric acid moiety, and 5) competitively inhibited by the vitamin pantothenic acid (inhibition constant of 14.4 microM). Pretreatment with the protein kinase C (PKC) activators phorbol 12-myristate 13-acetate (PMA) and 1, 2-dioctanoyl-sn-glycerol significantly inhibited biotin uptake. In contrast, pretreatment with the PKC inhibitors staurosporine and chelerythrine led to a slight, but significant, increase in biotin uptake. The effect of PMA was mediated via a marked decrease in maximal uptake velocity and a slight increase in apparent Km. Pretreatment of cells with modulators of the protein kinase A-mediated pathway, on the other hand, showed no significant effect on biotin uptake. These results demonstrate, for the first time, the functional existence of a Na+-dependent, specialized carrier-mediated system for biotin uptake in colonic epithelial cells. This system is shared with pantothenic acid and appears to be under the regulation of an intracellular PKC-mediated pathway.

Arterial occlusions as a presenting feature of acute promyelocytic leukemia

Arterial thrombosis as a presentation of acute promyelocytic leukemia is uncommon. The authors report a patient who presented with a clot in the left external iliac artery and pulmonary emboli. The literature is reviewed.

Dysplastic nitrergic neurons in the rectum of a patient with rectal ectasia

We present a histochemical study of resected colon from a 13-year-old boy diagnosed with rectal ectasia. Laminar preparations and sectioned tissue of rectum were assayed histochemically for nitric oxide (NO) synthase activity by reducing nitro blue tetrazolium salt in the presence of the cofactor NADPH. Tissue preparations displayed intensely labelled neurons and fibers throughout the gut wall. Laminar preparations of Meissner's plexus showed a hyperplasia of ganglia and NO-related neurons throughout the length of the resected rectum compared with normal bowel. Sectioned tissue of the Auerbach's plexus demonstrated a normal number of ganglia and NO-related neurons. As well, the ectatic bowel showed a proliferation of nerve fibers in keeping with the degree of circular smooth muscle hypertrophy. This proliferation may represent a reactive phenomenon secondary to the functional obstruction. The NO histochemical technique may form the basis of further investigations in defining the cause of this functional obstruction.

Minimum urine flow rate during water deprivation: importance of the nonurea versus total osmolality in the inner medulla

Antidiuretic hormone leads to an increase in the permeability for water and urea in the inner medullary collecting duct. Hence, urea may not be an "effective" osmole in the inner medulla during maximal renal water conservation. Accordingly, the purpose of this study was to evaluate whether differences in the rate of urea excretion would influence maximum renal water conservation in humans. In water-deprived rats, the concentration of urea and total osmolality were somewhat higher in the urine exiting the inner medullary collecting duct than in interstitial fluid obtained from the entire papillary tip. Nevertheless, the "nonurea" (total osmolality minus urea in millimolar terms) osmolality was virtually identical in both locations. Chronically fasted human subjects that were water-deprived for 16 h had a lower rate of urea excretion (71 +/- 7 versus 225 +/- 14 mumol/min) and a somewhat lower urine osmolality (745 +/- 53 versus 918 +/- 20 mosmol/kg H2O). Nevertheless, they had identical urine flow rates (0.5 +/- 0.01 and 0.5 +/- 0.02 ml/min, respectively), and their nonurea osmolality also was similar (587 +/- 25 and 475 +/- 14 mosmol/kg H2O, respectively) to the water-deprived normal subjects. The composition of their urine differed in that the principal nonurea osmoles became NH4+ and beta-hydroxybutyrate rather than Na and C1. During water deprivation in normal subjects, the ingestion of urea caused a twofold rise in urine flow rate, a fall in the nonurea osmolality, and a rise in the rate of excretion of nonurea osmoles. The nonurea osmolality of the urine, and presumably the medullary interstitial fluid as well, was inversely related to the urea excretion rate. In chronic fasting, the nature, but not the quantity, of nonurea osmoles changed. The similar minimum urine volume was predictable from an analysis based on nonurea osmole considerations.

Lower diagnostic accuracy of thallium-201 SPECT myocardial perfusion imaging in women: an effect of smaller chamber size

OBJECTIVES

We attempted to formally compare the diagnostic accuracy of thallium-201 single-photon emission computed tomographic (SPECT) myocardial perfusion imaging in men and women and the effect of chamber size on accuracy.

BACKGROUND

The diagnostic accuracy of conventional exercise testing has been shown to be lower in women. Less is known about the relative accuracy of perfusion imaging. Because of smaller body size, women have a smaller heart size than men, a factor that may reduce accuracy.

METHODS

We identified 323 patients undergoing thallium-201 SPECT myocardial perfusion imaging who either had < 5% probability of coronary artery disease (CAD) by Bayesian analysis or who underwent cardiac catheterization within 60 days of stress testing. Patients with documented history of infarction, coronary artery bypass grafting, pathologic Q waves on the electrocardiogram, left bundle branch block or nonischemic cardiomyopathy were not included. We performed strict quantitative analysis, and receiver operating characteristic (ROC) curves were generated and the area under the curve was calculated for men and women. A size index was generated from the number of short-axis slices and average radius of each slice, and the group was classified as having a large or a small chamber size. The ROC areas of men and women with a large and a small chamber size were then compared.

RESULTS

Diagnostic accuracy was lower in women than in men (ROC are 0.82 vs. 0.93, p < 0.05) despite similar values for peak heart rate and rate-pressure product and similar severity of CAD. There was a greater difference in accuracy between patients with a large versus a small chamber size (ROC area 0.94 vs. 0.73, p < 0.01) despite similar levels of exercise and severity of CAD. When we compared men and women in groups stratified by chamber size, we could not detect a significant difference between ROC area values of men and women (large: 0.94 men, 0.93 women, p = 0.77, power to detect difference in area of 0.15 = 91%; small: 0.79 men, 0.72 women, p = 0.58, power to detect difference in area of 0.15 = 35%).

CONCLUSIONS

The diagnostic accuracy of thallium SPECT myocardial perfusion imaging is lower in women than in men. Most of the difference appears to be due to smaller left ventricular chamber size in women, although a small residual gender effect in smaller heart sizes cannot be entirely excluded. It is proposed that the most likely cause for this difference is the relatively greater effect of imaging blurring on smaller hearts.

The relationship of thoracic lymphadenopathy to pulmonary interstitial disease in diffuse and limited systemic sclerosis: CT findings

OBJECTIVE

Mediastinal lymphadenopathy is frequently associated with interstitial lung disease (ILD) in patients with systemic sclerosis (SSc). This study compared the extent of lymphadenopathy in diffuse and limited SSc with the presence and type of ILD found on CT scans.

SUBJECTS AND METHODS

Seventy-three patients with diffuse and limited SSc underwent thoracic CT. The presence of lymphadenopathy was correlated with the frequency and type of ILD.

RESULTS

Fifty-eight percent (18/31) of patients with diffuse cutaneous SSc and 40% (17/42) of patients with limited cutaneous SSc had lymphadenopathy. A significant relationship was found between lymphadenopathy and the presence of interstitial disease (p = .0002). Seventy-two percent (18/25) of patients with a ground-glass parenchymal pattern of interstitial disease and 74% (14/19) of patients with a honeycomb pattern had lymphadenopathy.

CONCLUSION

Lymphadenopathy is prevalent in patients with SSc and ILD regardless of clinical subtype or interstitial pattern. Lymphadenopathy appears to increase as a function of the profusion rather than the morphology of ILD.

Evaluating a change in practice: femoral sheath removal by registered nurses

A descriptive study was conducted to assess whether there was a difference in patient outcomes when femoral venous and arterial sheaths were removed post percutaneous transluminal coronary angioplasty (PTCA) by MDs as compared to RNs. In addition, the impact on nursing practice of nurses assuming this new task was examined. A chart review revealed a greater occurrence of bleeding in patients whose sheaths had been removed by MDs rather than by RNs (chi square; p < 0.01). Patients received analgesics and anxiolytics pre-sheath removal more frequently when nurses removed femoral sheaths (p < 0.01). Forty-two percent of RNs were not satisfied with the change in practice, and 46% were satisfied. Further research is needed to evaluate patient satisfaction with pain and anxiety management at the time of sheath removal.

Randomized trial of interferon maintenance in multiple myeloma: a study of the National Cancer Institute of Canada Clinical Trials Group

PURPOSE

To determine whether interferon maintenance therapy improves overall survival and response duration in patients with multiple myeloma who have responded to induction therapy with melphalan and prednisone.

PATIENTS AND METHODS

In a multicenter trial, patients with symptomatic clinical stage I and stage II and III multiple myeloma were registered at diagnosis and those who responded to melphalan-prednisone (MP) were randomized either to receive interferon (2 mU/m2) subcutaneously three times per week or no maintenance. MP was discontinued in both groups once a stable response plateau of the monoclonal protein was reached. Interferon was continued until relapse, and then was restarted on subsequent response to MP. Interferon toxicity was recorded using a self-report diary. Survival and response duration were calculated using life-table methods, and were adjusted in the analysis for imbalances in baseline prognostic factors.

RESULTS

Four hundred two patients were registered and 176 responders were randomized (85 to interferon and 91 to control). At a median follow-up time of 43 months, the median survival duration was 43 months for interferon and 35 months for control (P = .16), but when adjusted for chance imbalances in baseline prognostic factors (mainly performance status), the median survival duration was 44 months and 33 months for interferon and control, respectively (P = .049). Progression-free survival from randomization to first relapse also favored interferon (unadjusted P < .002; adjusted P < .003). Interferon toxicity caused 58% of patients to reduce their dose, of which 84% were able to return to the initial dose; 14% had to discontinue interferon treatment.

CONCLUSION

Interferon maintenance therapy improves progression-free and overall survival of patients with multiple myeloma who respond to melphalan and prednisone. Toxicity is substantial and must be weighed by patients against the potential benefits in response duration and survival.

Testicular fate after incarcerated hernia repair and/or orchiopexy performed in patients under 6 months of age

This study assessed testicular viability after 476 inguinal procedures performed in 338 infants under 6 months of age, between 1974 and 1993. One hundred twenty-one elective hernia repairs (contralateral explorations) were compared with 355 hernia repairs complicated by incarceration and/or orchiopexy. Clinical examination of 323 testes in the early postoperative period showed 20 atrophic testes. Since January 1994, 71 of the 338 patients have had testicular measurements obtained through ultrasonography (US). An additional 13 atrophic testes were found during US examination. Of these, nine were believed to be normal during early postoperative examination. Assuming that US examination will confirm atrophy in the 20 atrophic testes noted early in the postoperative clinical evaluation, and that all other testes not yet scanned are found to be normal, the minimal atrophy rate (MAR) would be 9.3% (33 of 355). Neither operative nor early postoperative testicular assessment correlates with ultimate testicular survival. Testicular pathology may become more evident after puberty, and the real incidence of atrophy may increase.

Lids, lacrimals, and lashes

The eyelids and lashes serve to protect the globe from foreign bodies and injuries, and the lacrimal system protects the eyes through lubrication of the corneal and conjunctival surfaces. This article discusses trauma, infection, inflammation, anatomic abnormalities, and tumors that may result in serious complications interfering with normal eye function.

Gastrointestinal mucormycosis causing an acute abdomen in the immunocompromised pediatric patient--three cases

Mucormycosis is an infection caused by a ubiquitous fungus in immunocompromised individuals. Typically, it invades blood vessels, producing thrombosis and tissue infarction. This infection spans all pediatric age groups and can lead to hollow viscus perforation and bowel obstruction. A 30-month old male with large cell anaplastic lymphoma had a bowel obstruction. During emergency laparotomy, an ileoileal intussusception was identified, which required resection and anastomosis. In the pathological specimen, fungi of the Mucorales order were found to be associated with tissue necrosis. On the eighth day of life, a premature infant had abdominal distension secondary to bowel perforation. Partial gastric resection and multiple intestinal stomas were performed. Death occurred soon after, secondary to multiorgan failure. The autopsy and surgical specimens showed widespread mucormycosis. An adolescent had meningococcemia-induced septic shock. During recovery, hemorrhagic colitis developed, which led to perforation. The subtotal colectomy specimen showed widespread mucormycosis. The laparotomy findings are typical (black necrotic tissue involving the bowel), and when seen in the immunocompromised patient, should make one suspect gastrointestinal mucormycosis. Aggressive surgical debridement of devitalized tissue augmented by intravenous antifungal medication is the mainstay of treatment.

Distribution of nitric oxide synthase activity in arterioles and venules of rat and human intestine

NO is produced within peripheral blood vessels through the action of the differentially distributed constitutive and inducible NO synthase isoforms in the vessel wall. As in other sites in the periphery, NO exerts local vasodilatory actions in the gastrointestinal microvasculature and is proposed to play a role in enteric vasomotor regulation. Using NO synthase histochemistry and endothelial cell immunohistochemistry, we provide the first anatomic evidence of NO synthesis in both endothelial and smooth muscle cells of submucosal blood vessels in the rat and human intestine. The findings of this study indicate that 1) as in the periphery, both the endothelial and vascular smooth muscle cells of the microvessels irrigating the rat and human intestinal wall possess NO synthesis potential, 2) NO synthase activity is predominantly localized to discrete subcellular patches, and 3) the source of NO within the vascular wall, either intimal or medial, should be a consideration in future studies in terms of the relative contribution of these sources of vasomotor tone in the rat and human gut wall.

MR imaging: its role in detecting occult fractures

Magnetic resonance (MR) studies were performed on 30 consecutive patients who continued to be symptomatic despite negative or inconclusive findings on radiographs and other imaging studies including radionuclide bone scans, computed tomography, and/or polytomography. There were 9 men and 21 women, 20-92 years old (mean age 63 years) whose MR studies were done 3-72 h after frank trauma in 22 cases and in another 8 after 1-4 weeks of increasing pain subsequently attributed to trauma or unaccustomed effort. MR studies were performed using 0.5-T (Phillips) or 1.5-T (Phillips, GE) superconductive magnets. Results indicated that: (1) MR images allowed identification of acute fractures in an emergency room setting, as well as subtle subacute or chronic fractures in the context of strong clinical suspicions despite negative or inconclusive radiographs and other subsequently indecisive imaging studies. (2) MR imaging is the most sensitive way of documenting the earliest changes in traumatized osseous and soft tissue structures simultaneously.

Photoregulation of alpha-chymotrypsin activity in organic media: effects of bioimprinting

alpha-Chymotrypsin exhibits photoswitchable activities in an organic solvent after covalent modification of the protein backbone with thiophenefulgide active ester (2). The thiophenefulgide-modified alpha-chymotrypsin exhibits reversible photoisomerizable properties between states (3)-E and (3)-C. The modified alpha-chymotrypsin, where nine lysine residues are substituted by thiophenefulgide units, retains 60% of the activity of the native enzyme. The activities of thiophenefulgide-modified alpha-chymotrypsin toward esterification of N-acetyl-L-phenylalanine (4) by ethanol in cyclohexane are controlled by the configuration of the attached photoisomerizable component and by prior bioimprinting of the protein backbone with the reaction substrate (4). The esterification of (4) in cyclohexane using bioimprinted (3)-C is two-fold faster than in the presence of (3)-E. In the presence of a nonbioimprinted enzyme, esterification of (4) by (3)-C is five-fold faster than with (3)-E. The activity of bioimprinted (3)-E toward esterification of (4) is 4.5-fold higher than that of nonbioimprinted (3)-E. Switchable cyclic esterification of (4) is accomplished by sequential photoisomerization of the thiophenefulgide-modified alpha-chymotrypsin between states (3)-C and (3)-E.

Leukocyte involvement in cerebral infarct generation after ischemia and reperfusion

White blood cell involvement in the generation of cerebral infarcts was evaluated following ischemia and reperfusion injury in the rat. Control and leukopenic rats (induced by vinblastine, WBC counts < 1500/mm3) were compared in a global forebrain ischemic model after 1 h of ischemia and 1 h 15 min of reperfusion. Cerebral infarcts were defined on coronal brain sections using Triphenyl tetrazolium chloride (TTC) staining. Electroencephalographic activity (EEG) and somatosensory evoked potentials (SSEP) were also compared. Results indicate that the area infarcted in leukopenic rats was significantly less than infarcts generated in corresponding controls (21 +/- 16% vs. 70 +/- 16%). In addition, EEG was preserved in all leukopenic animals when compared to controls, both during ischemia and after reperfusion. The cortical peak component of the SSEP was also better preserved in the leukopenic animals both during ischemia and at 60 min of reperfusion. These results indicate white blood cell participation in the generation of cerebral damage in a model of global forebrain ischemia and reperfusion as indicated by TTC staining of cerebral infarcts.

Online repositioning during treatment of the prostate: a study of potential limits and gains

PURPOSE

With on-line portal imaging devices and image registration tools, the verification of radiation field position prior to each treatment becomes technically feasible. In this paper, we analyze the impact of pre-treatment verification and field position adjustment on target coverage and normal tissue sparing.

METHODS AND MATERIALS

Port films were compared with corresponding simulation films to determine the magnitude of setup variations in patients treated for prostate cancer. From these data, an analytic function was determined between geometric coverage of the target and field margin size. A paradigm for on-line patient repositioning was employed to generate a new relationship between margin and target coverage. Margins were selected for the situations of normal treatment and on-line repositioning to ensure target coverage. Dose-volume histograms were generated for a typical prostate treatment using these margins.

RESULTS

On-line repositioning, when setup errors exceed 1 cm, results in a 6 mm reduction in margin, suggesting that 10% of the volume of bladder and rectum may be spared of high dose.

CONCLUSION

The use of on-line imaging and image registration to guide adjustment of patient setup may lead to a reduction in the volume of normal tissues irradiated, and possibly improve the probability of complication-free survival in future treatments.

Effect of subcutaneous recombinant human erythropoietin in cancer patients receiving radiotherapy: preliminary results of a randomized, open-labeled, phase II trial

PURPOSE

To determine the efficacy and safety of subcutaneous administration of recombinant human erythropoietin (r-HuEPO) at a dose of 200 units/kg/day to cancer patients undergoing radiotherapy.

METHODS AND MATERIALS

This is a randomized, open-labeled, Phase II study. Only patients receiving radiotherapy +/- chemotherapy are included. Eligibility is restricted to patients with lung cancer, carcinoma of the uterine cervix, prostatic adenocarcinoma, or adenocarcinoma of the breast. Patients in the control and treatment arms receive radiotherapy with similar policies, and their doses of radiotherapy and treatment volumes are determined by the site and stage of the disease. Patients in the "treatment arm" receive 200 units/kg/day of r-HuEPO, subcutaneously, five times a week with iron (Fe SO4, 325 mg. p.o., t.i.d.) supplements. Complete blood counts are obtained weekly. Quality of life is assessed weekly by the patients themselves by a few simple entries on an analog scale.

RESULTS

Twenty-six patients have been entered in the study so far. Twelve patients were placed in the control arm and 14 in the treatment arm. Pre-randomization demographic and laboratory mean values in both arms were comparable, with none of 16 parameters compared reaching statistical significance. Our results can be summarized as follows: (a) Mean hemoglobin, hematocrit, and red blood cell values increased gradually in the treatment arm patients. Week-by-week comparison showed that mean values for these three parameters were significantly higher in the treatment arm than in the control arm. For example, the p values for the differences in hemoglobin mean values for weeks 1-6 were 0.015, 0.002, 0.003, 0.0002, 0.0006, and 0.007, respectively. Similar trends were observed for red blood cells and the hematocrit values. (b) No significant toxicity has been encountered. (c) No significant differences in the mean values of white blood cells and platelet counts were seen between the two arms. The values of these two parameters declined over the course of radiotherapy. (d) The mean weekly increase in hemoglobin levels in the treatment arm was 0.43 gm/dl.

CONCLUSION

(a) The safety and efficacy of r-HuEPO, with 200 units/kg/day of subcutaneous administration, have been confirmed in our study group. (b) However, the rate of increase in hemoglobin levels is not very rapid with the doses used. (c) Dose escalation studies are needed for determination of the feasibility of improving hemoglobin levels by about 1 gm/dl/week. (d) The question whether improvement in hemoglobin with r-HuEPO therapy can improve outcome by improving tumor oxygenation needs to be studied in carcinoma of the uterine cervix and squamous cell carcinoma of the head and neck.

Evidence supporting the superiority of intraperitoneal cisplatin compared to intraperitoneal carboplatin for salvage therapy of small-volume residual ovarian cancer

PURPOSE

To examine the relative efficacy of cisplatin-based intraperitoneal (IP) therapy versus carboplatin-based IP therapy as salvage treatment of small-volume residual ovarian cancer.

PATIENTS AND METHODS

We retrospectively examined the surgically defined response rates of patients with ovarian cancer treated at the Memorial Sloan-Kettering Cancer Center on four organoplatinum-based salvage IP trials (cisplatin/etoposide, cisplatin/cytarabine, carboplatin/etoposide, carboplatin/etoposide + recombinant human erythropoietin). Additional criteria for inclusion in this analysis were: (a) small-volume residual disease (microscopic disease only or largest residual tumor mass < or = 0.5 cm) when IP therapy was initiated; (b) prior response to organoplatinum-based systemic therapy; (c) laparotomy evaluation for response to the IP salvage program.

RESULTS

The surgically documented complete response rate for patients with microscopic disease treated with cisplatin-based or carboplatin-based therapy was 46% (6/13) versus 38% (6/16), respectively (P > 0.25). In contrast, the surgically documented overall and complete response rates for patients with small-volume macroscopic disease treated with cisplatin or carboplatin were 71% (12/17) versus 32% (6/19) (P < 0.05, chi 2 test with Yates' correction), and 41% (6/17) versus 11% (2/19) (p < 0.1), respectively.

CONCLUSION

In agreement with experimental data demonstrating that the concentration of platinum within tumor is higher following equimolar doses of cisplatin, compared to carboplatin, we have observed, in this retrospective analysis, a higher surgically documented response rate for patients with small-volume residual macroscopic ovarian cancer receiving salvage cisplatin-based IP therapy. While a randomized trial will be required to definitively address the question of the relative effectiveness of the two commercially available organoplatinum agents for IP treatment of ovarian cancer, our data suggest that cisplatin is the superior agent for regional therapy in this disease.

Mitomycin-C plus a 3-day continuous intravenous infusion of 5-fluorouracil: an inactive salvage regimen for platinum-resistant ovarian carcinoma

In a Phase II trial, patients with refractory ovarian cancer were given 10 mg/m2 mitomycin-C i.v. every 8 weeks and 1000 mg/m2/day 5-fluorouracil for 3 consecutive days by continuous intravenous infusion repeated every 4 weeks. Sixteen heavily pretreated patients with platinum-resistant disease were treated and no major responses were observed. Only 2 patients required subsequent dose reduction for myelotoxicity. No sign of gastrointestinal toxicity was seen. This regimen is inactive as salvage treatment for refractory ovarian cancer.

Diethyldithiocarbamate chemoprotection of carboplatin--induced hematological toxicity

Carboplatin therapy has a more favorable toxicity profile than cisplatin and, given in appropriate doses, is equivalent in efficacy to cisplatin for suboptimal ovarian cancer. However myelosuppression frequently curtails therapy with carboplatin. Diethyldithiocarbamate (DDTC) is a thiol compound and heavy-metal-chelating agent that has been shown to protect against carboplatin-induced bone marrow suppression in animal models. This pilot study was undertaken to evaluate the ability of DDTC to ameliorate the degree and/or duration of myelosuppression from carboplatin chemotherapy in patients with relapsed ovarian cancer. Ten patients who had previously demonstrated a response to platinum-based chemotherapy, were treated with single-agent intravenous carboplatin 400 mg/m2 administered over 30-60 min every 4 weeks. Patients received their first cycle of carboplatin without DDTC, and their second cycle with DDTC. DDTC at 600 mg/m2 was infused over 3 h commencing 30 min prior to carboplatin and was well tolerated. Treatment with DDTC did not decrease the degree of leukopenia or thrombocytopenia associated with carboplatin chemotherapy, nor did it decrease the duration of myelosuppression. This clinical study demonstrates no evidence of a bone-marrow-protective effect for this dose and schedule of DDTC in patients receiving carboplatin chemotherapy.