RADIOACTIVE IRON AND ITS METABOLISM IN ANEMIA : ITS ABSORPTION,TRANSPORTATION, AND UTILIZATION

Artificially produced radioactive iron is an extremely sensitive agent for use in following iron in the course of its changes in body metabolism, lending itself to studies of absorption, transport, exchange, mobilization, and excretion. The need of the body for iron in some manner determines the absorption of this element. In the normal dog when there is no need for the element, it is absorbed in negligible amounts. In the anemic animal iron is quite promptly assimilated. The plasma is clearly the means of transport of iron from the gastrointestinal tract to its point of mobilization for fabrication into hemoglobin. The speed of absorption and transfer of iron to the red cell is spectacular. The importance of the liver and bone marrow in iron metabolism is confirmed.     

The influence of aorta-aneurysm geometry upon stress in the aneurysm wall

Finite element analysis (FEA), a computer-based method for solving complex structural problems, was used to determine the wall stress distribution in three cases of model infrarenal abdominal aortic aneurysms representing common problems in determining risk of aneurysm rupture. The point of maximum circumferential wall stress in a spherical model aneurysm was located near the junction of the aneurysm and the nondilated aorta, while maximum longitudinal wall stress was located at the point of maximum diameter of the aneurysm. FEA showed that cylindrically shaped constant thickness model aneurysms had a higher maximum circumferential stress (sigma c = 11.9 X 10(5) dyn/cm2) and a comparable maximum longitudinal wall stress (sigma L = 6.6 X 10(5) dyn/cm2) when compared with spherical model aneurysms of the same diameter (sigma c = 8.1 X 10(5) dyn/cm2 and sigma L = 6.2 X 10(5) dyn/cm2). Analysis of the aorta to aneurysm diameter ratio (A:a gradient) indicated that aortic size is important in determining aneurysm wall stress and that the relationship between aortic size and wall stress is dependent upon aneurysm wall thickness. We conclude that the ability of the aneurysm wall to withstand stress in the longitudinal as well as the circumferential direction is an important factor determining aneurysm rupture. Finally, this investigation showed that FEA is a versatile tool for use in studying the mechanics of vascular structures, making it potentially more useful than size alone in estimating the clinical significance of abdominal aortic aneurysms.     

Early Data from the First Population-Wide Breast Cancer-Specific Registry in Hong Kong

Background

Current measures for breast cancer prevention and options for treatment adopted in Hong Kong are mainly based on research data and clinical evidence from overseas. It is essential to establish a cancer-specific registry to monitor the status of breast cancer in Hong Kong.

Objectives

We summarized the current status of breast cancer in Hong Kong based on the data collected from Hong Kong Breast Cancer Registry (HKBCR).

Methods

Prevalent and newly diagnosed breast cancers (including in situ and invasive breast cancers) were registered in the HKBCR. Information on patient demographics, risk factors, medical information, and survival were analyzed and reported in this study.

Results

Data of 2,330 breast cancer patients were analyzed. We observed an earlier median age at diagnosis in Hong Kong than those reported in other countries. Distribution of cancer stage was: stage 0 (11.4%), stage I (31.4%), stage II (41%), stage III (12.5%), stage IV (0.8%), and unclassified (2.9%). The percentages of patients who received surgery, chemotherapy, radiation therapy, and endocrine therapy were 98.7, 67.9, 64.8, and 64.1%, respectively. At a median follow-up of 1.2?years, locoregional recurrence was recorded at 2%, distant recurrence at 2.8%, and breast-cancer–related mortality at 0.3%.

Conclusions

The HKBCR serves as a surveillance program to monitor disease and treatment patterns. It is pivotal to support research for more effective breast cancer prevention and treatment strategies in Hong Kong.     

Clinical value of carcinoembryonic antigen: diagnosis, prognosis, and follow-up of patients with cancer.

Plasma carcinoembryonic antigen (CEA) in nanograms per milliliter was assayed in 149 patients with benign and 567 patients with malignant disease. Elevated CEA level (greater than 5.0) was a good indicator of malignant disease but a poor screening test for cancer because of the high false-negative rate. Degree of elevation of plasma CEA level correlated with incidence of metastatic disease in patients with colorectal, gastric, and breast carcinomas, but no correlation was seen between CEA levels and status of lymph nodes in patients with localized disease. Patients with localized colorectal cancer, but elevated CEA levels before resection, had a 2.1-fold increase in the incidence of recurrence; however, this added to the prognostic value of Dukes' staging only when the CEA level remained elevated postoperatively. In 87% of patients with colorectal cancer, the CEA level was elevated at the time of recurrence, but a therapeutic value of reexploration for unexplained CEA level elevation was not confirmed.     

Tim-3 mediates T cell trogocytosis to limit antitumor immunity

T cell immunoglobulin mucin domain-containing protein 3 (Tim-3) negatively regulates innate and adaptive immunity in cancer. To identify the mechanisms of Tim-3 in cancer immunity, we evaluated the effects of Tim-3 blockade in human and mouse melanoma. Here, we show that human programmed cell death 1–positive (PD-1⁺) Tim-3⁺CD8⁺ tumor-infiltrating lymphocytes (TILs) upregulate phosphatidylserine (PS), a receptor for Tim-3, and acquire cell surface myeloid markers from antigen-presenting cells (APCs) through transfer of membrane fragments called trogocytosis. Tim-3 blockade acted on Tim-3⁺ APCs in a PS-dependent fashion to disrupt the trogocytosis of activated tumor antigen–specific CD8⁺ T cells and PD-1⁺Tim-3⁺ CD8⁺ TILs isolated from patients with melanoma. Tim-3 and PD-1 blockades cooperated to disrupt trogocytosis of CD8⁺ TILs in 2 melanoma mouse models, decreasing tumor burden and prolonging survival. Deleting Tim-3 in dendritic cells but not in CD8⁺ T cells impeded the trogocytosis of CD8⁺ TILs in vivo. Trogocytosed CD8⁺ T cells presented tumor peptide–major histocompatibility complexes and became the target of fratricide T cell killing, which was reversed by Tim-3 blockade. Our findings have uncovered a mechanism Tim-3 uses to limit antitumor immunity.     

Pretest and change score intercorrelations in the validation of behavioral measures of openness

Two behavioral measures of openness (a miniature situations test and a structured self-disclosure interview), two self-report measures of openness (the Dogmatism Scale and the Experience Inventory), and the Ego-strength Scale were administered to 50 Ss on two different occasions spaced several weeks apart. One of the behavioral measures, the miniature situations test, correlated positively with the other measures of openness on the pretest. With regard to change scores across the two sessions, the behavioral measures correlated positively with each other and negatively with the self-report measures of openness and with the Ego-strength Scale. These results were interpreted as supporting the theoretical supposition that behavioral measures are most suitable for the measurement of short-term change in openness.     

Treatment Options for Patellofemoral Arthritis

Purpose of ReviewTo present a synthesis of recent literature regarding the treatment of patellofemoral arthritisRecent FindingsRisk factors of PFJ OA include patella malalignment or maltracking, injury to supportive structures including the MPFL, dysfunction of hamstring and quadriceps coordination, lower limb alignment, trochlear dysplasia, patellar trauma, or ACL surgery. Special physical exam maneuvers include patellar grind test, apprehension test, and lateral patellar tilt angle. Radiographs that should be obtained first-line include weight bearing bilateral AP, lateral, and Merchant views. CT and MRI are used to assess trochlear dysplasia, excessive patellar height, and TT-TG distance. Non-operative management options discussed include non-pharmacologic treatment (patient education, self-management, physical therapy, weight loss), ESWT, cold therapy, taping, bracing, and orthotics. Pharmacologic management options discussed include NSAIDs, acetaminophen, oral narcotics, and duloxetine. Injection therapies include glucocorticoids, hyaluronic acid, PRP, and other regenerative therapies (BMAC, adipose, or mesenchymal stem cells). Other treatment options include radiofrequency ablation and botulinum toxin. The algorithm for the surgical treatment of PFJ OA can begin with arthroscopic assessment of the PF articular cartilage to address mechanical symptoms and to evaluate/treat lateral soft tissue with or without overhanging lateral osteophytes. If patients fail to have symptomatic improvement, a TTO can be considered in those patients less than 50 years of age or active patients >50 years old. In patients with severe PFJ OA, refractory to the above treatments, PFA should be considered. While early PFA design and technique were less than encouraging, more recent implant design and surgical technique have demonstrated robust results in the literature.SummaryPatellofemoral osteoarthritis is a challenging orthopedic problem to treat, in that it can often affect younger patients, with otherwise well-functioning knees. It is a unique entity compared to TF OA with distinct epidemiology, biomechanics and risk factors and treatment options.     

Management of biliary obstruction in patients with unresectable carcinoma of the pancreas.

Clinical and pathologic data from 73 patients with unresectable carcinoma of the pancreas treated from 1980 to 1987 were reviewed to evaluate the efficacy of biliary enteric bypass and percutaneous transhepatic biliary drainage (PTBD) in the treatment of malignant biliary obstruction. Fifty-two patients underwent biliary enteric bypass with no operative deaths and with a 15% operative morbidity. These patients had a median postoperative hospitalization of 12 days. Four patients (8%) eventually developed recurrent jaundice, and three of these were successfully treated with PTBD. The median survival for these 52 patients was 7 months. Twenty-one patients underwent PTBD with an 81% technical-success rate. These patients had a 33% early complication rate and a 33% in-hospital mortality. The median hospitalization was 13 days postdrainage. Of the 14 patients surviving the initial hospitalization, 86% developed late complications requiring 16 hospital admissions and ten emergency room visits for a total of 155 days of hospitalization. The median survival for those patients undergoing PTBD was 4 months from the time of diagnosis and 2 months from the time of catheter drainage. Surgical bypass offers excellent palliation for malignant biliary obstruction with extremely low morbidity and mortality in properly selected patients; PTBD is useful in the treatment of those patients with extensive disease, who are poor surgical candidates, or who have failed previous surgical drainage. There is a role for both of these palliative procedures in the management of patients with biliary obstruction from pancreatic cancer.     

Primary and staged transposition arteriovenous fistulas

BACKGROUND: The use of catheters or prosthetic grafts for vascular access has significantly higher mortality and morbidity risks, in addition to higher costs, than arteriovenous fistulas (AVF). Many patients have a difficult access extremity due to complex medical illnesses, previous vascular access procedures, intravenous catheters, diabetes, vascular disease, female sex, age, and other complicating factors. Transposition AVFs (AVF-T) have been used for these individuals to avoid catheters and grafts. We report our experience with primary and staged basilic vein AVF-Ts and staged brachial vein AVF-Ts. METHODS: From our database of consecutive vascular access operations, we reviewed patients from May 2003 to September 2006 for all upper extremity AVF-Ts. A primary AVF-T was used when the basilic vein was continuous with a minimum diameter of 4 mm and of adequate length. When the basilic vein was 2.5 to 4 mm, the procedure was staged. The proximal radial artery was used for inflow, if possible. When the basilic vein was not suitable, a radial vein or brachial vein anastomosis was performed as the first stage of a planned brachial vein AVF-T. The second stage operations of staged AVF-Ts were generally done 4 to 6 weeks after the primary AVF construction. All patients were evaluated with preoperative ultrasound imaging by the operating surgeon. RESULTS: From a database of 412 consecutive vascular access patients, 78 upper extremity transposition procedures were identified. Of these, 57 patients (73.1%) were women, 44 (56.4%) were diabetic, and 46 (59.0%) had previous access surgery. Fifty-eight operations were staged procedures. The basilic vein was used in 68 AVF-T, the brachial vein in six, and cephalic vein in four. The anastomosis was based on the proximal radial artery in 60 patients. Mean follow-up was 18 months (range, 3-48 months). Primary patency, primary assisted patency, and cumulative patency were 45.7%, 93.5%, and 96.0% at 12 months and 27.6%, 86.5%, and 88.9% at 24 months, respectively. No prosthetic grafts were used in the study period. CONCLUSION: Both primary and staged AVF-T procedures were successfully used in patients with difficult access extremities. AVF-Ts were durable, although many required an interventional procedure for maturation or maintenance. Cumulative (secondary) patency was 96.0% at 12 months and 88.9% at 24 months. The absence of an adequate basilic vein does not preclude the use of a staged AVF-T because the brachial vein offers a suitable alternative.