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1.
Br J Surg ; 108(10): 1207-1215, 2021 10 23.
Article in English | MEDLINE | ID: mdl-34095952

ABSTRACT

BACKGROUND: Long-term survival outcomes of trimodal therapy (TMT; chemoradiation plus surgery) and bimodal therapy (BMT; chemoradiation) have seldom been analysed. In a selective-surgery paradigm, the benefit of TMT in patients with a complete clinical response is controversial. Factors associated with survival in patients with a clinical complete response to chemoradiation were evaluated. METHODS: Patients with stage II-III oesophageal squamous cell carcinoma treated with TMT or BMT from 2002 to 2017 were evaluated. The BMT group consisted of patients who were otherwise eligible for surgery but underwent chemoradiation alone followed by observation. This group included patients who later had salvage oesophagectomy. Survival was evaluated and compared between TMT and BMT groups. Elastic net regularization was performed to select co-variables for Cox multivariable survival analysis in patients with a clinical complete response. RESULTS: Of 143 patients, 60 (41.9 per cent) underwent TMT and 83 (58.0 per cent) BMT. Patients who underwent TMT had longer median overall survival than those who had BMT (77 versus 33 months; P = 0.019). For patients with a clinical complete response, TMT achieved longer median overall survival than BMT (123 versus 55 months; P = 0.04). BMT had a high locoregional recurrence rate (48 versus 6 per cent; P < 0.001); 26 of 29 patients with locoregional recurrence in the BMT groupunderwent salvage resection. Cox multivariable analysis demonstrated that upper-mid oesophageal tumour location (hazard ratio (HR) 2.04; P = 0.024) and tumour length (HR 1.18; P = 0.046) were associated with worse survival. Although TMT was not associated with survival, it was a predictor of reduced recurrence (HR 0.28; P = 0.028). The maximum standardized uptake value after chemoradiation also predicted recurrence (HR 1.33; P < 0.001). CONCLUSION: In patients who achieve a clinical complete response, TMT reduces locoregional recurrence but may not prolong survival. The differences in survival outcomes may be due to patient selection; therefore, a selective-surgery strategy in oesophageal squamous cell carcinoma is a reasonable approach.


Subject(s)
Esophageal Neoplasms/therapy , Esophageal Squamous Cell Carcinoma/therapy , Aged , Chemoradiotherapy, Adjuvant , Disease-Free Survival , Esophageal Neoplasms/mortality , Esophageal Neoplasms/pathology , Esophageal Neoplasms/surgery , Esophageal Squamous Cell Carcinoma/mortality , Esophageal Squamous Cell Carcinoma/pathology , Esophageal Squamous Cell Carcinoma/surgery , Esophagectomy , Female , Humans , Male , Middle Aged , Neoadjuvant Therapy , Neoplasm Metastasis , Neoplasm Recurrence, Local , Neoplasm Staging , Proportional Hazards Models , Salvage Therapy
2.
Dis Esophagus ; 33(3)2020 Mar 16.
Article in English | MEDLINE | ID: mdl-31313820

ABSTRACT

The survival advantage associated with the addition of surgical therapy in esophageal squamous cell carcinoma (ESCC) patients who demonstrate a complete clinical response to chemoradiotherapy is unclear, and many institutions have adopted an organ-preserving strategy of selective surgery in this population. We sought to characterize our institutional experience of salvage esophagectomy (for failure of definitive bimodality therapy) and planned esophagectomy (as a component of trimodality therapy) by retrospectively analyzing patients with ESCC of the thoracic esophagus and GEJ who underwent esophagectomy following chemoradiotherapy between 2004 and 2016. Of 76 patients who met inclusion criteria, 46.1% (35) underwent salvage esophagectomy. Major postoperative complications (major cardiovascular and pulmonary events, anastomotic leak [grade ≥ 2], and 90-day mortality) were frequent and occurred in 52.6% of the cohort (planned resection: 36.6% [15/41]; salvage esophagectomy: 71.4% [25/35]). Observed rates of 30- and 90-day mortality for the entire cohort were 7.9% (planned: 7.3% [3/41]; salvage: 8.6% [3/35]) and 13.2% (planned: 9.8% [4/41]; salvage: 17.1% [6/35]), respectively. In summary, esophagectomy following chemoradiotherapy for ESCC at our institution has been associated with frequent postoperative morbidity and considerable rates of mortality in both planned and salvage settings. Although a selective approach to surgery may permit organ preservation in many patients with ESCC, these results highlight that salvage esophagectomy for failure of definitive-intent treatment of ESCC may also constitute a difficult clinical undertaking in some cases.


Subject(s)
Chemoradiotherapy , Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Esophagectomy , Postoperative Complications , Chemoradiotherapy/adverse effects , Chemoradiotherapy/methods , Combined Modality Therapy/methods , Combined Modality Therapy/statistics & numerical data , Esophageal Neoplasms/mortality , Esophageal Neoplasms/pathology , Esophageal Neoplasms/surgery , Esophageal Squamous Cell Carcinoma/mortality , Esophageal Squamous Cell Carcinoma/pathology , Esophageal Squamous Cell Carcinoma/surgery , Esophagectomy/adverse effects , Esophagectomy/methods , Female , Humans , Male , Middle Aged , Neoplasm Staging , Outcome and Process Assessment, Health Care , Postoperative Complications/diagnosis , Postoperative Complications/epidemiology , Salvage Therapy/methods , Salvage Therapy/statistics & numerical data
4.
Ann Oncol ; 24(11): 2844-9, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23975663

ABSTRACT

BACKGROUND: The contribution of induction chemotherapy (IC) before preoperative chemoradiation for esophageal cancer (EC) is not known. We hypothesized that IC would increase the rate of pathologic complete response (pathCR). METHODS: Trimodality-eligibile patients were randomized to receive no IC (Arm A) or IC (oxaliplatin/FU; Arm B) before oxaliplatin/FU/radiation. Surgery was attempted ∼5-6 weeks after chemoradiation. The pathCR rate, post-surgery 30-day mortality, overall survival (OS), and toxic effects were assessed. Bayesian methods and Fisher's exact test were used. RESULTS: One hundred twenty-six patients were randomized dynamically to balance the two arms for histology, baseline stage, gender, race, and age. Fifty-five patients in Arm A and 54 in Arm B underwent surgery. The median actuarial OS for all patients (54 deaths) was 45.62 months [95% confidence interval (CI), 27.63-NA], with median OS 45.62 months (95% CI 25.56-NA) in Arm A and 43.68 months (95% CI 27.63-NA) in Arm B (P = 0.69). The pathCR rate in Arm A was 13% (7 of 55) and 26% (14 of 54) in Arm B (two-sided Fisher's exact test, P = 0.094). Safety was similar in both arms. CONCLUSIONS: These data suggest that IC produces non-significant increase in the pathCR rate and does not prolong OS. Further development of IC before chemoradiation may not be beneficial. Clinical trial no.: NCT 00525915 (www.clinicaltrials.gov).


Subject(s)
Chemoradiotherapy , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/radiotherapy , Induction Chemotherapy , Adult , Aged , Bayes Theorem , Cisplatin/administration & dosage , Combined Modality Therapy , Esophageal Neoplasms/mortality , Esophageal Neoplasms/pathology , Esophageal Neoplasms/surgery , Female , Fluorouracil/administration & dosage , Follow-Up Studies , Humans , Male , Middle Aged , Organoplatinum Compounds/administration & dosage , Oxaliplatin , Preoperative Period , Remission Induction
5.
Ann Oncol ; 24(1): 67-74, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23002278

ABSTRACT

BACKGROUND: The purpose of this study was to evaluate the actuarial risk of local and regional failure in patients with completely resected non-small-cell lung cancer (NSCLC), and to assess surgical and pathological factors affecting this risk. PATIENTS AND METHODS: Between January 1998 and December 2009, 1402 consecutive stage I-III (N0-N1) NSCLC patients underwent complete resection without adjuvant radiation therapy. The median follow-up was 42 months. RESULTS: Local-regional recurrence was identified in 9% of patients, with local failure alone in 3% of patients, regional failure alone in 4% of patients, and both local and regional failure simultaneously in 2% of patients. Patients who had local failure were found to be at increased risk of mortality. By multivariate analyses, three variables were shown to be independently significant risk factors for local [surgical procedure (single/multiple wedges+segmentectomy versus lobectomy+bilobectomy+pneumonectomy), tumor size>2.7 cm, and visceral pleural invasion] and regional (pathologic N1 stage, visceral pleural invasion, and lymphovascular space invasion, LVI) recurrence, respectively. CONCLUSION: Patients with N0-N1 disease have low rates of locoregional recurrence after surgical resection. However, several prognostic factors can be identified that increase this risk and identify patients who may benefit from adjuvant treatment.


Subject(s)
Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/pathology , Neoplasm Recurrence, Local , Patient Selection , Adult , Aged , Aged, 80 and over , Area Under Curve , Carcinoma, Non-Small-Cell Lung/radiotherapy , Carcinoma, Non-Small-Cell Lung/surgery , Female , Humans , Lung Neoplasms/radiotherapy , Lung Neoplasms/surgery , Male , Middle Aged , ROC Curve , Risk Factors
6.
Ann Oncol ; 24(5): 1262-6, 2013 May.
Article in English | MEDLINE | ID: mdl-23247658

ABSTRACT

BACKGROUND: Chemoradiation followed by surgery is the preferred treatment of localized gastroesophageal cancer (GEC). Surgery causes considerable life-altering consequences and achievement of clinical complete response (clinCR; defined as postchemoradiation [but presurgery] endoscopic biopsy negative for cancer and positron emission tomographic (PET) scan showing physiologic uptake) is an enticement to avoid/delay surgery. We examined the association between clinCR and pathologic complete response (pathCR). PATIENTS AND METHODS: Two hundred eighty-four patients with GEC underwent chemoradiation and esophagectomy. The chi-square test, Fisher exact test, t-test, Kaplan-Meier method, and log-rank test were used. RESULTS: Of 284 patients, 218 (77%) achieved clinCR. However, only 67 (31%) of the 218 achieved pathCR. The sensitivity of clinCR for pathCR was 97.1% (67/69), but the specificity was low (29.8%; 64/215). Of the 66 patients who had less than a clinCR, only 2 (3%) had a pathCR. Thus, the rate of pathCR was significantly different in patients with clinCR than in those with less than a clinCR (P < 0.001). CONCLUSIONS: clinCR is not highly associated with pathCR; the specificity of clinCR for pathCR is too low to be used for clinical decision making on delaying/avoiding surgery. Surgery-eligible GEC patients should be encouraged to undergo surgery following chemoradiation despite achieving a clinCR.


Subject(s)
Chemoradiotherapy , Esophageal Neoplasms/therapy , Stomach Neoplasms/therapy , Cohort Studies , Combined Modality Therapy , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/radiotherapy , Esophageal Neoplasms/surgery , Female , Humans , Male , Middle Aged , Positron-Emission Tomography , Remission Induction , Retrospective Studies , Stomach Neoplasms/drug therapy , Stomach Neoplasms/radiotherapy , Stomach Neoplasms/surgery , Treatment Outcome
7.
Ann Oncol ; 23(10): 2638-2642, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22831985

ABSTRACT

BACKGROUND: Approximately 25% of patients with esophageal cancer (EC) who undergo preoperative chemoradiation, achieve a pathologic complete response (pathCR). We hypothesized that a model based on clinical parameters could predict pathCR with a high (≥60%) probability. PATIENTS AND METHODS: We analyzed 322 patients with EC who underwent preoperative chemoradiation. All the patients had baseline and postchemoradiation positron emission tomography (PET) and pre- and postchemoradiation endoscopic biopsy. Logistic regression models were used for analysis, and cross-validation via the bootstrap method was carried out to test the model. RESULTS: The 70 (21.7%) patients who achieved a pathCR lived longer (median overall survival [OS], 79.76 months) than the 252 patients who did not achieve a pathCR (median OS, 39.73 months; OS, P = 0.004; disease-free survival, P = 0.003). In a logistic regression analysis, the following parameters contributed to the prediction model: postchemoradiation PET, postchemoradiation biopsy, sex, histologic tumor grade, and baseline (EUS)T stage. The area under the receiver-operating characteristic curve was 0.72 (95% confidence interval [CI] 0.662-0.787); after the bootstrap validation with 200 repetitions, the bias-corrected AU-ROC was 0.70 (95% CI 0.643-0.728). CONCLUSION: Our data suggest that the logistic regression model can predict pathCR with a high probability. This clinical model could complement others (biomarkers) to predict pathCR.


Subject(s)
Esophageal Neoplasms/pathology , Combined Modality Therapy , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/radiotherapy , Humans , Multivariate Analysis , Survival Analysis
8.
Dis Esophagus ; 25(7): 614-22, 2012.
Article in English | MEDLINE | ID: mdl-22150920

ABSTRACT

High body mass index (H-BMI; ≥25 kg/m(2) ) is common in US adults. In a small cohort of esophageal cancer (EC) patients treated with surgery, H-BMI and diagnosis of early stage EC appeared associated. We evaluated a much larger cohort of EC patients. From a prospectively maintained database, we analyzed 925 EC patients who had surgery with or without adjunctive therapy. Various statistical methods were used. Among 925 patients, 69% had H-BMI, and 31% had normal body mass index (<25 kg/m(2) ; N-BMI). H-BMI was associated with men (P<0.001), Caucasians (P=0.064; trend), lower esophageal localization (P<0.001), adenocarcinoma histology (P<0.001), low baseline cT-stage (P=0.003), low baseline overall clinical stage (P=0.003), coronary artery disease (P=0.036), and diabetes (P<0.001). N-BMI was associated with weight loss (P<0.001), alcohol abuse (P=0.056; trend), ever/current smoking (P=0.014), and baseline cN+ (P=0.018). H-BMI patients with cT1 tumors (n=110) had significantly higher rates of gastresophageal reflux disease symptoms (P<0.001), gastresophageal reflux disease history (P<0.001), and Barrett's esophagus history (P<0.001) compared with H-BMI patients with cT2 tumors (n=114). Median survival of N-BMI patients was 36.66 months compared with 53.20 months for H-BMI patients (P=0.005). In multivariate analysis, older age (P<0.001), squamous histology (P=0.002), smoking (P=0.040), weight loss (P=0.002), high baseline stage (P<0.001), high number of ypN+ (P=0.005), high surgical stage (P<0.001), and American Society of Anesthesia scores, three out of four (P<0.001) were independent prognosticators for poor overall survival. We were able to perform propensity-based analysis of surgical complications between H-BMI and N-BMI patients. A comparison of fully matched 376 patients (188 with H-BMI and 188 with N-BMI) found no significant differences in the rate of complications between the two groups. This larger data set confirms that a fraction of H-BMI patients with antecedent history is diagnosed with early baseline EC. Upon validation of our data in an independent cohort, refinements in surveillance of symptomatic H-BMI patients are warranted and could be implemented. Our data also suggest that H-BMI patients do not experience higher rate of surgical complications compared with N-BMI patients.


Subject(s)
Adenocarcinoma/diagnosis , Carcinoma, Squamous Cell/diagnosis , Esophageal Neoplasms/diagnosis , Overweight/complications , Adenocarcinoma/complications , Adenocarcinoma/pathology , Age Factors , Aged , Body Mass Index , Carcinoma, Squamous Cell/complications , Carcinoma, Squamous Cell/pathology , Cohort Studies , Esophageal Neoplasms/complications , Esophageal Neoplasms/pathology , Esophageal Squamous Cell Carcinoma , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Neoplasm Staging , Obesity/complications , Retrospective Studies , Sex Factors , Survival Rate , Time Factors
9.
Neurotoxicol Teratol ; 2009 Feb 05.
Article in English | MEDLINE | ID: mdl-19201157

ABSTRACT

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

10.
J Hand Microsurg ; 1(1): 3-6, 2009 Jun.
Article in English | MEDLINE | ID: mdl-23129924

ABSTRACT

BACKGROUND: Non-suturing alternatives to expedite a microanastomoses while still insuring maximum patency rates to date have best been achieved using everting ring-pin devices. Although these so-called couplers have heretofore primarily been used for the venous microanastomosis during free flap transfers, they have also had limited value for their arterial counterpart. METHODS: Applications for use of the microanastomotic coupler has been extended to repair solitary arterial injuries in the distal upper extremity. Over the past year, 4 patients specifically with hand or forearm arterial injuries alone, had rapid coupling of the injured vessels. RESULTS: Direct end-to-end repair of all hand or forearm arterial injuries using a microanastomotic coupler was possible in 3 of four cases. Because of the greater extent of injury, the exception required an interposition vein graft; but that too was coupled to each end of the divided artery in end-to-end fashion. In no case was there any compromise of vascular patency. CONCLUSION: Although hand perfusion in no individual in this series was ever at jeopardy because of persistent collaterals, this demonstration of the efficiency and efficacy of this device may justify future use for critical limb revascularisation.

12.
Dis Esophagus ; 19(3): 152-7, 2006.
Article in English | MEDLINE | ID: mdl-16722991

ABSTRACT

The purpose of this study was to identify gender-dependent differences in presentation at baseline and therapy outcome in esophageal carcinoma patients treated with preoperative chemoradiotherapy (CTRT). We stratified patients according to gender and statistically compared pretreatment clinical stage, post-CTRT effect on carcinoma in the resected specimen, overall survival (OS), and patterns of failure. Of the 235 patients who underwent preoperative CTRT, 203 were men and 32 were women. Carcinomas in women correlated significantly with clinical stage II classification (78%vs. 55%) while cancers in men correlated significantly with clinical stage III classification (39%vs. 16%; P = 0.02). Carcinomas in women also correlated significantly with lower clinical N classification; more women had cN0 (52%) compared to men (28%; P = 0.01). Similarly, in the surgical specimens, more women had pN0 (78%) compared to men (64%; P = 0.06). At a median follow-up of 37 months, 10% more women than men remain alive (63%vs. 53%; P = 0.3). Distant metastases-free survival time was longer for women than men. Our results suggest that localized esophageal carcinoma is diagnosed in more advanced stages in men than in women. The reasons for these differences remain unclear and further expansion of these observations and study of biologic differences that might exist are warranted.


Subject(s)
Chemotherapy, Adjuvant , Esophageal Neoplasms/epidemiology , Esophageal Neoplasms/therapy , Neoadjuvant Therapy , Radiotherapy, Adjuvant , Disease Progression , Disease-Free Survival , Esophageal Neoplasms/diagnosis , Esophageal Neoplasms/pathology , Female , Humans , Male , Neoplasm Recurrence, Local/epidemiology , Neoplasm Staging , Prognosis , Retrospective Studies , Sex Factors , Treatment Outcome
13.
World J Surg ; 25(5): 562-6, 2001 May.
Article in English | MEDLINE | ID: mdl-11369980

ABSTRACT

Duodenal leiomyomas are rare neoplasms and when present are usually asymptomatic. There are, however, isolated case reports of such leiomyomas giving rise to complications including gastrointestinal hemorrhage and obstruction. The purpose of this study was to review the surgical experience with duodenal leiomyomas at a large tertiary referral center. A retrospective review was performed of all patients with histologically proven duodenal leiomyomas encountered from 1975 to 1995. Twelve patients with surgically treated duodenal leiomyomas were identified. There were eight men and four women with a mean age of 57 years (range 20-73 years) at diagnosis. Anemia was the presenting sign in 10 patients (83%). The mean hemoglobin level at presentation was 10.8 +/- 2.67 g/dl. Other presenting signs included melena (n = 5) and epigastric tenderness (n = 4). No patient had obstructive symptoms. Upper endoscopy visualized the lesion in 9 of 10 patients, but endoscopic biopsy provided an accurate histologic diagnosis in only two of six patients biopsied. All resected specimens underwent frozen section and permanent histopathologic analysis. Local excision was performed in eight patients, as benignancy was anticipated at surgical exploration and frozen section findings. Two patients underwent segmental duodenal resection with primary end-to-end anastomosis, and two patients underwent a Whipple procedure. There was no perioperative mortality. Morbidity was minimal. There was no tumor recurrence during a median follow-up of 8.4 years. Gastrointestinal blood loss is the most common complication of duodenal leiomyomas requiring surgical intervention. Small symptomatic leiomyomas with benign features may be safely treated with local excision.


Subject(s)
Duodenal Neoplasms/surgery , Leiomyoma/surgery , Adult , Aged , Anemia/etiology , Duodenal Neoplasms/complications , Duodenal Neoplasms/diagnostic imaging , Female , Humans , Leiomyoma/complications , Leiomyoma/diagnostic imaging , Male , Middle Aged , Radiography , Retrospective Studies
14.
Ann Plast Surg ; 47(6): 647-51, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11756836

ABSTRACT

Many methods have been used to measure experimental flap survival in animal models. These have previously included planimetry, computer programs, and (routinely by the authors) the simple measurement of the weight of a template traced according to the dimensions of a given flap. To test the validity of their method, an alternative technique was developed by the authors' biostatiticians. Initially, in a study of rat transverse rectus abdominis musculocutaneous (TRAM) flaps, all templates were also scanned electronically to form bitmaps. Using commonly available software programs, each bitmap was colorized corresponding to viable and nonviable areas of the flaps. A summation of individual pixels by color could then be used to calculate the percentage of flap survival. A comparison of both methodologies in 64 rat TRAM flaps found that the survival rate was slightly greater overall when a computer analysis had been performed (3.1 +/- 1.7%), but this was not a significant difference (p = 0.479). Thus, the previous standard method was proven reliable, but just as precise calculations are now possible using the convenience of any personal computer.


Subject(s)
Mathematical Computing , Rectus Abdominis/transplantation , Animals , Graft Survival , Models, Animal , Organ Size , Rats , Rats, Sprague-Dawley , Rectus Abdominis/anatomy & histology , Software , Surgical Flaps
15.
Neurotoxicol Teratol ; 22(4): 521-31, 2000.
Article in English | MEDLINE | ID: mdl-10974590

ABSTRACT

Visual thresholds for luminance increments were obtained behaviorally and electrophysiologically from rats exposed to a polychlorinated biphenyl (PCB) during development. Male Long-Evans rats exposed to 0, 0.25, or 1.0 microg/kg/day of 3,3',4,4', 5-pentachlorobiphenyl (PCB 126) through gestation and weaning were trained as adults to perform a signal detection task. Estimates of threshold were derived from psychometric functions for each animal relating the proportion of hits to signal intensity. Thresholds derived under three luminance conditions did not differ significantly among the PCB-treated groups. After behavioral testing was completed, flash-evoked potentials were recorded from dark-adapted awake animals. Peak amplitudes increased linearly over approximately 3 log units of intensity. Extrapolations to 0 amplitude along the linear portion of the amplitude-log intensity functions produced estimates of absolute threshold of -5.44 to -5.53 log cd/m(2)-s. Waveforms recorded from awake animals had a large late negative component that was absent in previously reported anesthetized preparations. Developmental exposure to PCB 126 had no significant effect on absolute threshold or peak amplitudes and latencies.


Subject(s)
Behavior, Animal/drug effects , Polychlorinated Biphenyls/pharmacology , Prenatal Exposure Delayed Effects , Visual Perception/drug effects , Animals , Dose-Response Relationship, Drug , Electrophysiology , Evoked Potentials, Visual/drug effects , Female , Male , Photic Stimulation , Pregnancy , Psychomotor Performance/drug effects , Rats , Rats, Long-Evans , Sensory Thresholds/drug effects , Thyroid Gland/drug effects , Thyroid Gland/metabolism , Thyroxine/blood , Thyroxine/drug effects , Wakefulness
16.
Environ Health Perspect ; 108 Suppl 3: 405-8, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10852836

ABSTRACT

Attention deficit hyperactivity disorder (ADHD) is a disability that affects between 3 and 7% of children, with a significant number of individuals continuing to be affected into adolescence and adulthood. ADHD is characterized in part by an inability to organize complex sequences of behavior, to persist in the face of distracting stimuli, and to respond appropriately to the consequences of past behavior. There are some parallels between the features of ADHD and the behavior of monkeys exposed developmentally to lead or polychlorinated biphenyls (PCBs), as evidenced by research from our laboratory. Both lead and PCB exposure produce deficits on discrimination reversal and spatial delayed alternation performance; treated monkeys exhibit deficits in their ability to change an already established response strategy and inhibit inappropriate responses. Monkeys exposed developmentally to lead or PCBs also perform differently from control monkeys on a fixed interval schedule of reinforcement, which requires the temporal organization of behavior using only internal cues. Whereas the etiology of ADHD is multifactorial, the possibility that neurotoxic agents in the environment contribute to the incidence of ADHD warrants attention.


Subject(s)
Attention Deficit Disorder with Hyperactivity/etiology , Haplorhini/physiology , Neurotoxins/adverse effects , Animals , Behavior, Animal/drug effects , Discrimination Learning , Disease Models, Animal , Environmental Pollutants/adverse effects , Humans , Polychlorinated Biphenyls/adverse effects
17.
Environ Health Perspect ; 108 Suppl 3: 535-44, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10852852

ABSTRACT

This paper summarizes the deliberations of a work group charged with addressing specific questions relevant to risk estimation in developmental neurotoxicology. We focused on eight questions. a) Does it make sense to think about discrete windows of vulnerability in the development of the nervous system? If it does, which time periods are of greatest importance? b) Are there cascades of developmental disorders in the nervous system? For example, are there critical points that determine the course of development that can lead to differences in vulnerabilities at later times? c) Can information on critical windows suggest the most susceptible subgroups of children (i.e., age groups, socioeconomic status, geographic areas, race, etc.)? d) What are the gaps in existing data for the nervous system or end points of exposure to it? e) What are the best ways to examine exposure-response relationships and estimate exposures in vulnerable life stages? f) What other exposures that affect development at certain ages may interact with exposures of concern? g) How well do laboratory animal data predict human response? h) How can all of this information be used to improve risk assessment and public health (risk management)? In addressing these questions, we provide a brief overview of brain development from conception through adolescence and emphasize vulnerability to toxic insult throughout this period. Methodological issues focus on major variables that influence exposure or its detection through disruptions of behavior, neuroanatomy, or neurochemical end points. Supportive evidence from studies of major neurotoxicants is provided.


Subject(s)
Brain/drug effects , Brain/growth & development , Developmental Disabilities/diagnosis , Xenobiotics/adverse effects , Adolescent , Brain/embryology , Child , Child, Preschool , Embryonic and Fetal Development , Humans , Infant , Infant, Newborn , Neuronal Plasticity , Neurons/drug effects , Neurons/physiology , Neurotoxins/adverse effects , Public Health , Risk Assessment , Time Factors
18.
J Surg Oncol ; 73(4): 224-7, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10797336

ABSTRACT

BACKGROUND AND OBJECTIVES: Postoperative wound seromas are a frequent and troublesome occurrence after mastectomy. Recent reports have suggested the efficacy of topical sclerosants at reducing their formation. METHODS: A prospective, randomized, double-blinded trial was performed to examine the effect of intraoperatively administered topical tetracycline on the occurrence of postoperative mastectomy seromas. Thirty-two women were randomized to the control arm (normal saline) and 30 women to the tetracycline arm. In the treatment group, 100 ml (2 g) of tetracycline solution was administered topically to the chest wall and skin flaps prior to skin closure. The control group received an equal volume of normal saline. Patients were monitored for the development of postoperative wound seroma. RESULTS: There were no significant differences between groups regarding total volume of closed suction drainage, numbers of patients leaving hospital with drains in place, or duration of catheter drainage. Seroma formation 2 weeks postoperatively was greater in the tetracycline group than the control group (53% vs. 22%, P = 0.01). There were no differences between groups regarding the degree of postoperative pain, wound infection, or seroma formation 1 month postoperatively. CONCLUSIONS: Topical tetracycline is not effective at preventing post-mastectomy wound seromas.


Subject(s)
Intraoperative Care , Mastectomy, Modified Radical , Protein Synthesis Inhibitors/therapeutic use , Sclerosing Solutions/therapeutic use , Sclerotherapy , Tetracycline/therapeutic use , Administration, Topical , Breast Neoplasms/surgery , Carcinoma, Ductal, Breast/surgery , Carcinoma, Intraductal, Noninfiltrating/surgery , Catheterization/instrumentation , Chi-Square Distribution , Double-Blind Method , Drainage/instrumentation , Exudates and Transudates , Female , Follow-Up Studies , Humans , Mastectomy, Modified Radical/adverse effects , Pain, Postoperative/etiology , Prospective Studies , Protein Synthesis Inhibitors/administration & dosage , Sclerosing Solutions/administration & dosage , Sodium Chloride , Suction , Surgical Wound Infection/etiology , Tetracycline/administration & dosage
20.
Neurotoxicology ; 21(6): 1039-44, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11233750

ABSTRACT

The Faroe Islands study is a prospective study designed to assess the neurological and behavioral consequences of in utero exposure to methylmercury (meHg). Maternal exposure to meHg was through consumption of fish and intermittent higher-level exposure through pilot whale meat, while consumption of pilot whale blubber resulted in maternal exposure to PCBs. Analysis of the neurobehavioral domains affected revealed impairment in attention, memory, and auditory processing, impairment in primary auditory function, and to a lesser extent motor impairment. For four of the eight endpoints affected by meHg exposure atp < .10, impairment was also correlated (p < .10) with in utero PCB exposure as measured by cord tissue PCB levels. Further analyses provide evidence for an independent effect of PCBs and meHg on these endpoints. Cross-sectional studies in a smaller number of children in the Amazon and Madeira by the same group of investigators, in which average meHg maternal hair levels were about twice as high those in the Faroe Islands, identified auditory, visual, and/or motor deficits, with little or no evidence of deficits in attention or memory. However, the results of the cross-sectional studies must be interpreted with caution, due to limited statistical power as well as a lack of opportunity to correlate effects to in utero exposure.


Subject(s)
Methylmercury Compounds/toxicity , Neurotoxicity Syndromes/physiopathology , Animals , Brazil/epidemiology , Denmark/epidemiology , Environmental Exposure , Humans , Longitudinal Studies , Mediterranean Islands/epidemiology , Neurotoxicity Syndromes/epidemiology , Neurotoxicity Syndromes/psychology , Polychlorinated Biphenyls/toxicity
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