General ecological models for human subsistence, health and poverty.

The world's rural poor rely heavily on their immediate natural environment for subsistence and suffer high rates of morbidity and mortality from infectious diseases. We present a general framework for modelling subsistence and health of the rural poor by coupling simple dynamic models of population ecology with those for economic growth. The models show that feedbacks between the biological and economic systems can lead to a state of persistent poverty.

Poverty, disease, and the ecology of complex systems.

Understanding why some human populations remain persistently poor remains a significant challenge for both the social and natural sciences. The extremely poor are generally reliant on their immediate natural resource base for subsistence and suffer high rates of mortality due to parasitic and infectious diseases. Economists have developed a range of models to explain persistent poverty, often characterized as poverty traps, but these rarely account for complex biophysical processes.

Disease ecology, biodiversity, and the latitudinal gradient in income.

While most of the world is thought to be on long-term economic growth paths, more than one-sixth of the world is roughly as poor today as their ancestors were hundreds of years ago. The majority of the extremely poor live in the tropics. The latitudinal gradient in income is highly suggestive of underlying biophysical drivers, of which disease conditions are an especially salient example.

Poverty trap formed by the ecology of infectious diseases.

While most of the world has enjoyed exponential economic growth, more than one-sixth of the world is today roughly as poor as their ancestors were many generations ago. Widely accepted general explanations for the persistence of such poverty have been elusive and are needed by the international development community. Building on a well-established model of human infectious diseases, we show how formally integrating simple economic and disease ecology models can naturally give rise to poverty traps, where initial economic and epidemiological conditions determine the long-term trajectory of the health and economic development of a society.

Does failure to visualize a sentinel node on preoperative lymphoscintigraphy predict a greater likelihood of axillary lymph node positivity?

Background: Sentinel lymph node (SLN) mapping has become the standard of care for axillary staging in women with early-stage breast cancer. The purpose of the study was to investigate the hypothesis that nonvisualization of SLN on lymphoscintigraphy (LSG) predicts a subset of patients at risk of having a substantial burden of axillary tumor as evidenced by higher rate of lymph node involvement.

Study Design: We retrospectively reviewed the records of 1,500 patients who underwent dual-tracer SLN mapping for breast cancer between 1999 and 2004.

Predictors of residual invasive disease after core needle biopsy diagnosis of ductal carcinoma in situ.

Core needle biopsy (CNB) is used to sample both mammographically and ultrasound detected breast lesions. A diagnosis of ductal carcinoma in situ (DCIS) by CNB does not ensure the absence of invasive cancer upon surgical excision and as a result an upstaged patient may need to undergo additional surgery for axillary nodal evaluation. This study evaluates the accuracy of CNB in excluding invasive disease and the preoperative features that predict upstaging of DCIS to invasive breast cancer.

Placement technique and the early complications of balloon breast brachytherapy: Magee-Womens Hospital experience.

Backgrounds And Objectives: Open (OT) and percutaneous closed (PCT) techniques have been described for placement of the MammoSite catheter to deliver accelerated partial breast brachytherapy. We report early complications of both techniques.

Methods: A total of 125 patients underwent catheter placement for MammoSite high-dose rate brachytherapy, with 108 patients successfully completing treatment.

Is routine sentinel lymph node biopsy indicated in women undergoing contralateral prophylactic mastectomy? Magee-Womens Hospital experience.

Introduction: The routine use of sentinel node biopsy (SLNB) at the time of prophylactic mastectomy remains controversial. This retrospective study was undertaken to determine if SLNB is justified in patients undergoing CPM.

Methods: Between 1999 and 2004, 155 patients underwent contralateral prophylactic mastectomy (CPM) at the Magee-Womens Hospital of University of Pittsburgh Medical Center.

Preemptive analgesia with bupivacaine for segmental mastectomy.

Background And Objectives: Preemptive analgesia is the concept of providing analgesia before surgical incision, resulting in less postoperative pain. The purpose of this study is to determine if preemptive and/or postoperative local anesthetic infiltration of bupivacaine in patients undergoing segmental mastectomy results in less postoperative pain compared with patients receiving placebo.

Methods: In this prospective, double-blinded study, 120 patients were randomized into 4 groups: group 1, preincisional (10 mL) and postoperative (10 mL) wound infiltration of 0.

Higher disease prevalence can induce greater sociality: a game theoretic coevolutionary model.

There is growing evidence that communicable diseases constitute a strong selective force on the evolution of social systems. It has been suggested that infectious diseases may determine upper limits of host sociality by, for example, inducing territoriality or early juvenile dispersal. Here we use game theory to model the evolution of host sociality in the context of communicable diseases.

Selective intraoperative consultation for the evaluation of sentinel lymph nodes in breast cancer.

Background: Routine intraoperative evaluation of sentinel lymph nodes (SLNs) in breast cancer suffers from lack of sensitivity and consumes both time and resources. Failure to perform immediate consultation requires node-positive patients to return for delayed dissection.

Methods: We sought to determine whether selective use of intraoperative pathology consultation (IOC), based on the surgeon's clinical suspicion for metastases, would be accurate, avoid unnecessary consultations, and have a similar rate of delayed axillary dissection.