Large-area periodically-poled lithium niobate wafer stacks optimized for high-energy narrowband terahertz generation

Periodically-poled lithium niobate (PPLN) sources consisting of custom-built stacks of large-area wafers provide a unique opportunity to systematically study the multi-cycle terahertz (THz) generation mechanism as they are assembled layer-by-layer. Here we investigate and optimize the THz emission from PPLN wafer stacks as a function of wafer number, pump fluence, pulse duration and chirp, wafer separation, and pump focusing. Using 135 µm-thick, 2"-diameter wafers we generate high-energy, narrowband THz pulses with central frequencies up to 0.39 THz, directly suitable for THz-driven particle acceleration applications. We explore the multi-cycle pulse build-up with increasing wafer numbers using electro-optic sampling measurements, achieving THz conversion efficiencies up to 0.17%, while demonstrating unique control over the pulse length and bandwidth these sources offer. Guided by simulations, observed frequency-dependence on both stack-mounting and pump focusing conditions have been attributed to inter-wafer etalon and Gouy phase-shifts respectively, revealing subtle features that are critical to the understanding and performance of PPLN wafer-stack sources for optimal narrowband THz generation.

EPIC: an evaluation of the psychological impact of early-phase clinical trials in cancer patients

Background

Anxiety and depression in patients with cancer is associated with decreased quality of life and increased morbidity and mortality. However, these are often overlooked and untreated. Early-phase clinical trials (EPCTs) recruit patients with advanced cancers who frequently lack future treatment options, which may lead to increased anxiety and depression. Despite this, EPCTs do not routinely consider psychological screening for patients.

Patients and methods

This prospective observational study explored levels of anxiety and depression alongside impact of trial participation in the context of EPCTs. The Hospital Anxiety and Depression Scale and the Brief Illness Perceptions Questionnaire were completed at the point of EPCT consent, the end of screening and at pre-specified time points thereafter.

Results

Sixty-four patients (median age 56 years; median Eastern Cooperative Oncology Group performance status 1) were recruited. At consent, 57 patients returned questionnaires; 39% reported clinically relevant levels of anxiety whilst 18% reported clinically relevant levels of depression. Sixty-three percent of patients experiencing psychological distress had never previously reported this. Males were more likely to be depressed (P = 0.037) and females were more likely to be anxious (P = 0.011). Changes in anxiety or depression were observed after trial enrolment on an individual level, but not significant on a population level.

Conclusions

Patients on EPCTs are at an increased risk of anxiety and depression but may not seek relevant support. Sites offering EPCTs should consider including psychological screening to encourage a more holistic approach to cancer care and consider the sex of individuals when tailoring psychological support to meet specific needs.

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Early-phase cancer trial patients have an increased risk of anxiety and depression.

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Patients at risk were not seeking support for anxiety and depression.

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Male patients were more likely to be depressed; female patients were more likely to be anxious.

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This work highlights the need to screen for psychological symptoms in patients entering early-phase trials.

A phase I study of binimetinib (MEK 162), a MEK inhibitor, plus carboplatin and pemetrexed chemotherapy in non-squamous non-small cell lung cancer

INTRODUCTION

MEK inhibition is a potential therapeutic strategy in non-small cell lung cancer (NSCLC). This phase I study evaluates the MEK inhibitor binimetinib plus carboplatin and pemetrexed in stage IV non-squamous NSCLC patients (NCT02185690).

METHODS

A standard 3 + 3 dose-escalation design was used. Binimetinib 30 mg BID (dose level 1 [DL1]) or 45 mg BID (dose level 2 [DL2]) was given with standard doses of carboplatin and pemetrexed using an intermittent dosing schedule. The primary outcome was determination of the recommended phase II dose (RP2D) and safety of binimetinib. Secondary outcomes included efficacy, pharmacokinetics, and an exploratory analysis of response based on mutation subtype.

RESULTS

Thirteen patients (6 DL1, 7 DL2) were enrolled: 7 KRAS, 5 EGFR, and 1 NRAS mutation. The RP2D was binimetinib 30 mg BID. Eight patients (61.5%) had grade 3/4 adverse events, with dose limiting toxicities in 2 patients at DL2. Twelve patients were evaluated for response, with an investigator-assessed objective response rate (ORR) of 50% (95% CI 21.1%-78.9%; ORR 33.3% by independent-review, IR), and disease control rate 83.3% (95% CI 51.6%-97.9%). Median progression free survival (PFS) was 4.5 months (95% CI 2.6 months-NA), with a 6-month and 12-month PFS rate of 38.5% (95% CI 19.3%-76.5%) and 25.6% (95% CI 8.9%-73.6%), respectively. In an exploratory analysis, KRAS/NRAS-mutated patients had an ORR of 62.5% (ORR 37.5% by IR) vs. 25% in KRAS/NRAS wild-type patients. In MAP2K1-mutated patients, the ORR was 42.8%.

CONCLUSION

The addition of binimetinib to carboplatin and pemetrexed appears to have manageable toxicity with evidence of activity in advanced non-squamous NSCLC.

A randomized trial of the electronic Lung Cancer Symptom Scale for quality-of-life assessment in patients with advanced non-small-cell lung cancer

Introduction

Improving health-related quality of life (hrqol) is a key goal of systemic therapy in advanced lung cancer, although routine assessment remains challenging. We analyzed the impact of a real-time electronic hrqol tool, the electronic Lung Cancer Symptom Scale (elcss-ql), on palliative care (pc) referral rates, patterns of chemotherapy treatment, and use of other supportive interventions in patients with advanced non-small-cell lung cancer (nsclc) receiving first-line chemotherapy.

Methods

Patients with advanced nsclc starting first-line chemotherapy were randomized to their oncologist receiving or not receiving their elcss-ql data before each clinic visit. Patients completed the elcss-ql at baseline, before each chemotherapy cycle, and at subsequent follow-up visits until disease progression. Prospective data about the pc referral rate, hrqol, and use of other supportive interventions were collected.

Results

For the 95 patients with advanced nsclc who participated, oncologists received real-time elcss-ql data for 44 (elcss-ql arm) and standard clinical assessment alone for 51 (standard arm). The primary endpoint, the pc referral rate, was numerically higher, but statistically similar, for patients in the elcss-ql and standard arms. The hrqol scores over time were not significantly different between the two study arms.

Conclusions

The elcss-ql is feasible as a tool for use in routine clinical practice, although no statistically significant effect of its use was demonstrated in our study. Improving access to supportive care through the collection of patient-reported outcomes and hrqol should be an important component of care for patients with advanced lung cancer.

Observation of the Δg mechanism resulting from the ultrafast spin dynamics that follow the photolysis of coenzyme B12

Throughout nature, both free radicals and transient radical reaction intermediates are vital to many biological functions. Coenzyme B₁₂ is a case in point. This organometallic cofactor generates a radical pair upon activation in its dependent enzymes by substrate binding and following photolysis. The resulting cob(ii)alamin/5'-deoxyadenosyl radical pair has unusual magnetic properties that present a challenge to detailed investigation at ambient temperatures. Here, we use femtosecond transient absorption spectroscopy adapted for magnetic field exposure to reveal that the spin dynamics of the B₁₂ radical pair are sufficiently fast for magnetic field effects to be observed on the ultrafast reaction kinetics. Moreover, the large difference in g-values between the radicals of the pair means that effects of the Δg mechanism are observed for the first time for a radical pair system exposed to magnetic fields below 1 T. Spin dynamic simulations allow a value of the cob(ii)alamin radical g-value (2.105) at ambient temperature to be extracted and, because the spin dynamic time scale is faster than the diffusional rotation of the cob(ii)alamin radical, the observed value corresponds to the anisotropic g_|| value for this radical.

Demonstration of sub-luminal propagation of single-cycle terahertz pulses for particle acceleration

The sub-luminal phase velocity of electromagnetic waves in free space is generally unobtainable, being closely linked to forbidden faster than light group velocities. The requirement of sub-luminal phase-velocity in laser-driven particle acceleration schemes imposes a limit on the total acceleration achievable in free space, and necessitates the use of dispersive structures or waveguides for extending the field-particle interaction. We demonstrate a travelling source approach that overcomes the sub-luminal propagation limits. The approach exploits ultrafast optical sources with slow group velocity propagation, and a group-to-phase front conversion through nonlinear optical interaction. The concept is demonstrated with two terahertz generation processes, nonlinear optical rectification and current-surge rectification. We report measurements of longitudinally polarised single-cycle electric fields with phase and group velocity between 0.77c and 1.75c. The ability to scale to multi-megavolt-per-metre field strengths is demonstrated. Our approach paves the way towards the realisation of cheap and compact particle accelerators with femtosecond scale control of particles.Controlled generation of terahertz radiation with subluminal phase velocities is a key issue in laser-driven particle acceleration. Here, the authors demonstrate a travelling-source approach utilizing the group-to-phase front conversion to overcome the sub-luminal propagation limit.

Is chemotherapy always required for cancer in pregnancy? An observational study

BACKGROUND

Cancer in pregnancy is relatively rare, but the incidence is increasing. Several studies show that cytotoxic agents are safe to use in pregnancy from the second trimester onwards.

AIMS

This study assesses the maternal and foetal outcomes of cancers diagnosed during pregnancy. In particular, it focuses on a subset of women who elected to defer systemic chemotherapy until after delivery. This study examines if all cancers need to be treated during pregnancy or if, in certain cases, treatment can be safely deferred until after full-term delivery.

METHODS

This is a retrospective observational study of women diagnosed with cancer during pregnancy in an Irish cancer centre over a 27-year period. All women diagnosed with cancer during pregnancy who were referred to the medical oncology department for consideration of chemotherapy were included in this study. Medical and pharmacy records were extensively reviewed.

RESULTS

Twenty-five women were diagnosed with cancer in pregnancy and referred to medical oncology for consideration of systemic chemotherapy. Sixteen women (64%) commenced chemotherapy during pregnancy, seven women (28%) did not receive chemotherapy while pregnant, but commenced treatment immediately after delivery, and two (8%) did not receive any systemic chemotherapy at all. Of the seven women who commenced chemotherapy after delivery, six (85.7%) were diagnosed before 30/40 gestation. There were three cases of Hodgkin's lymphoma, two breast cancers and one ovarian cancer. After a median follow-up of 12 years, all six mothers remain disease-free.

CONCLUSIONS

This study identified a select cohort of patients that did not receive chemotherapy during pregnancy. There were no adverse outcomes to mothers due to delayed treatment.

Electronic Structure of a Mixed-Metal Fluoride-Centered Triangle Complex: A Potential Qubit Component

A novel fluoride-centered triangular-bridged carboxylate complex, [Ni2Cr(μ3-F)(O2C(t)Bu)6(HO2C(t)Bu)3] (1), is reported. Simple postsynthetic substitution of the terminal pivalic acids in 1 with pyridine and 4-methylpyridine led to the isolation of [Ni2Cr(μ3-F)(O2C(t)Bu)6(C5H5N)3] (2) and [Ni2Cr(μ3-F)(O2C(t)Bu)6((4-CH3)C5H4N)3] (3). Structural and magnetic characterizations carried out on the series reveal a dominating antiferromagnetic interaction between the nickel and chromium centers leading to an S = (1)/2 ground state with a very unusual value of geff = 2.48.

Role of misalignment-induced angular chirp in the electro-optic detection of THz waves

A general description of electro-optic detection including non-collinear phase matching and finite transverse beam profiles is presented. It is shown theoretically and experimentally that non-collinear phase matching in ZnTe (and similar materials) produces an angular chirp in the χ(2)-generated optical signal. Due to this, in non-collinear THz and probe arrangements such as single-shot THz measurements or through accidental misalignment, measurement of an undistorted THz signal is critically dependent on having sufficient angular acceptance in the optical probe path. The associated spatial walk-off can also preclude the phase retardation approximation used in THz-TDS. The rate of misalignment-induced chirping in commonly used ZnTe and GaP schemes is tabulated, allowing ready analysis of a detection system.

Dynamics in next-generation solar cells: time-resolved surface photovoltage measurements of quantum dots chemically linked to ZnO (101̄0)

The charge dynamics at the surface of the transparent conducting oxide and photoanode material ZnO are investigated in the presence and absence of light-harvesting colloidal quantum dots (QDs). The time-resolved change in surface potential upon photoexcitation has been measured in the m-plane ZnO (101̄0) using a laser pump-synchrotron X-ray probe methodology. By varying the oxygen annealing conditions, and hence the oxygen vacancy concentration of the sample, we find that dark carrier lifetimes at the ZnO surface vary from hundreds of μs to ms timescales, i.e. a persistent photoconductivity (PPC) is observed. The highly-controlled nature of our experiments under ultra-high vacuum (UHV), and the use of band-gap and sub-band-gap photoexcitation, allow us to demonstrate that defect states ca. 340 meV above the valence band edge are directly associated with the PPC, and that the PPC mediated by these defects dominates over the oxygen photodesorption mechanism. These observations are consistent with the hypothesis that ionized oxygen vacancy states are responsible for the PPC in ZnO. The effect of chemically linking two colloidal QD systems (type I PbS and type II CdS–ZnSe) to the surface has also been investigated. Upon deposition of the QDs onto the surface, the dark carrier lifetime and the surface photovoltage are reduced, suggesting a direct injection of charge carriers into the ZnO conduction band. The results are discussed in the context of the development of next-generation solar cells.

Episodic gross hematuria in association with allergy symptoms in a child

BACKGROUND

A relationship between allergy and the development of various renal diseases has been postulated, but never proven.

MATERIALS AND METHODS

We present the case of a child with idiopathic episodic gross hematuria. The child also has significant environmental allergies, and his episodes of hematuria coincide with flares of his allergic symptoms. The available literature on hematuria and allergy was reviewed in order to further explore the potential role that allergy may play in the pathogenesis of genitourinary tract disease.

CONCLUSIONS

This case, as well as others reported in the literature, suggest that allergy should be considered as a possible diagnosis in children with otherwise unexplained hematuria.

Complementary/alternative medicine in the treatment of asthma

OBJECTIVE

This review will familiarize clinical allergists/immunologists with the common forms of complementary/alternative medicine (CAM) that are being used frequently by their patients. It reviews reasons that patients seek alternative health care therapies and the most common illnesses that are treated with this form of medicine. Cultural differences in CAM are also reviewed. The article focuses on specific therapies used to treat asthma and reviews the efficacy of these therapies based on the available scientific literature. The reader will also learn about views of other physicians on CAM and how this topic is being addressed in US medical schools.

DATA SOURCES

Computer-assisted MEDLINE searches for articles on "complementary/alternative medicine" or "herbal therapy" and "asthma" or "atopy."

STUDY SELECTION

Pertinent abstracts and articles in the above areas were selected. Articles selected for detailed review included review articles of the subjects along with randomized, double-blind placebo-controlled studies in animals and humans.

RESULTS

Complementary/alternative medicine is commonly used by patients with chronic conditions including asthma. One-third of the US population has tried CAM. The literature supporting the efficacy of these therapies is lacking. Some reports elucidate the mechanism of action of certain herbal therapies that could possibly be helpful in the treatment of allergic diseases. There are, however, few well-controlled studies that support the efficacy of CAM in the treatment and clinical improvement of human subjects with asthma or atopic disorders.

CONCLUSION

Available scientific evidence does not support a role for CAM in the treatment of asthma. The studies in the literature often have significant design flaws that weaken the conclusions such as insufficient numbers of patients, lack of proper controls, and inadequate blinding. Further studies are needed to prove or disprove the efficacy of CAM. Physicians often find CAM intimidating because they are unaware of the clinical evidence and feel uncomfortable advising their patients on its efficacy. There is definitely a need for more education among physicians in this area. It is also important that physicians inquire and discuss the use of CAM with their patients since the majority of patients are using some form of CAM.

Emergency physician attitudes concerning intervention for alcohol abuse/dependence delivered in the emergency department: a brief report

Emergency Medicine (EM) physicians frequently see patients with alcohol abuse or dependence (AA/AD). Brief interventions delivered in the Emergency Department (ED) have been advocated for these patients, however, little is known regarding EM physician willingness to support such interventions. We conducted a study to determine EM physicians' attitudes toward the use of interventions for AA/AD in the ED. All members of the Michigan College of Emergency Physicians (n = 569) were mailed a survey to assess their attitudes toward the use of intervention for AA/AD in the ED. Of the 257 respondents (45.9%), a total of 76% agreed that AA/AD is a treatable illness and only 15% would not agree to support of ED interventions. Both supporters and non-supporters thought that the lack of sufficient time was an impediment to treating AA/AD in the ED. Our study suggests that the majority of ED physicians would support the implementation of brief intervention for AA/AD in the ED.

Impact of changes in asthma severity on health-related quality of life in pediatric and adult asthma patients: results from the asthma outcomes monitoring system

The goals of asthma treatment have broadened beyond managing traditional clinical markers of disease severity, and now include a focus on benefits of treatment in terms that are most meaningful to patients. Measurement of both generic and disease-specific health-related quality of life (HQL) is advocated because each provides complementary information about how the condition affects everyday functioning and well-being and whether treatments have their intended effects. The purpose of this study was to determine the impact of changes in asthma severity (defined using NHLBI/NAEPP severity staging) on patient-assessed HQL. Two hundred and thirty-three pediatric asthma patients and 269 adult asthma patients were evaluated in a one-year observational study. Analyses were performed to compare the generic and asthma-specific scores for patients whose asthma severity improved, stayed the same, or worsened over one year. The asthma-specific scales are sensitive to changes in disease severity. Of the generic scales, those tapping areas of physical health are more affected than the mental/emotional scales. This confirms that HQL measures are responsive to changes in asthma severity. They complement traditional clinical markers used to evaluate changes in a patient's disease state and thus give the physician another useful tool in following the clinical progress of the child with asthma.

Low level CD20 expression on T cell malignancies

Although initially thought to be a B lineage restricted antigen, low "density" or antibody binding capacity (ABC) CD20 has recently been detected on subset(s) of normal T lymphocytes (Hultin et al.: Cytometry 14:196-204, 1993). We report low ABC CD20 expression in three (two children, one adult) cases of T-acute lymphoblastic leukemia (T-ALL). CD20 and other pertinent antigens were detected using a direct dual color method with a Becton Dickinson FACScan flow cytometer and Simulset software. Only one cell population based on light scatter was noted in each case that immunophenotypically represented almost a pure population of malignant cells expressing T lymphocyte antigens (for example, CD7 98%, 92%, and 100%, respectively). A total of 95%, 87%, and 79% of the cells from the three cases expressed CD20 with an unusual low ABC compared to the customary "bright" CD20 expression on normal B lymphocytes. Other B lymphocyte associated antigens, such as CD19, CD22, Dr, and immunoglobulin light chains, were negative. Eleven other T lymphocytic malignancies from 1991 to 1993 were CD20 negative, including three other case of T-ALL (one adult and two children). One unusual case of intestinal small lymphocytic non-Hodgkin's lymphoma with a natural killer/T lymphocytic immunophenotype not described in this report appeared to be CD20"dim"+. Low ABC CD20 expression by T lymphocytic malignancies may provide a more unique immunophenotypic "fingerprint" to help support the diagnosis of T cell neoplasia vs. normal/reactive T cells (for example, low ABC CD20 cells represent only 2.4 +/- 1.5% of normal peripheral blood lymphocytes). This characteristic might also facilitate monitoring patients for residual or recurrent disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Orbital lymphoma associated with acquired immune deficiency syndrome (AIDS)

A new case of AIDS-associated, small noncleaved cell (Burkitt's) lymphoma that presented as an orbital mass is described. Extraocular muscle involvement was documented by computed tomography and confirmed by orbital biopsy. Extensive abdominal involvement was subsequently diagnosed and this caused the patient's death only 15 days after the initial consultation and orbital biopsy. A literature review discloses only eight previous case reports of AIDS-associated non-Hodgkin's lymphoma (NHL) involving the orbit: two cases of Burkitt's type and six cases of large cell immunoblastic type. Three additional cases of orbital NHL can be found among larger series of AIDS cases. Affected patients are uniformly young adult males with a history of homosexuality and/or IV drug abuse. Variations in clinical presentation are discussed. Although the morphology of the histopathologic specimen in our case was consistent with a high-grade, small noncleaved cell NHL, flow cytometry revealed an atypical immunophenotype for Burkitt's lymphoma in that CD20 and immunoglobulin light chain antigens were not expressed. Morphologic classification and immunophenotypic characteristics of AIDS-associated NHLs are discussed.

Comparison of type I and type II Chlamydia psittaci strains infecting koalas (Phascolarctos cinereus)

The native Australian marsupial Phascolarctos cinereus, otherwise known as the koala, is prone to infection by the obligate intracellular parasite Chlamydia psittaci, which causes ocular 'pink eye' and urogenital 'dirty tail' diseases. Several chlamydial DNA probes to both chromosomal and plasmid sequences were used to type by Southern blot analysis 51 samples taken from wild and captive koalas from habitats on the eastern seaboard of Australia as far apart as Queensland and Victoria. Two types of C. psittaci were observed and called types I and II. Type II was found more frequently than type I and occurred in both ocular and urogenital samples, while type I showed a strong but not absolute preference for ocular sites. Cross-hybridization analyses indicated that type I and type II had about 10% DNA sequence identity to each other. DNA analyses showed that type II was very closely related to some ovine and bovine chlamydiae but type I could not be related to any other C. psittaci strain available. Light and electron microscopic analyses of infected BGM monolayers revealed that the two strains were similar in morphological characteristics. The type I strain was considerably more infectious than the type II strain in BGM cells and in the yolk sacs of embryonated eggs. A PCR based assay detected both type I and type II koala chlamydiae in samples that had been negative by Southern blot and tissue culture and provided the first evidence that both types can occur simultaneously at the one site of infection.

Recurrence of hepatitis B and delta hepatitis after orthotopic liver transplantation

The clinical course of 10 liver transplant recipients who had hepatitis B virus (HBV) and five recipients with HBV and D (delta) infection before transplantation is described. Six patients who underwent eight transplants died. The estimated one and two year survival rates in patients with HBV only before transplantation were 74% and 67% respectively. The estimated one and two year survival in patients with HBV and HDV infection beforehand was 100%. Graft infection by HBV occurred in 8 of 10 patients infected with HBV only; and in 4 of 5 patients with previous HBV and HDV infection. There was a widely variable time from transplantation to the appearance of HBV markers in liver or serum, ranging from 6-331 days. Hepatitis D antigen (HDAg) appeared in three grafts very rapidly after transplantation at 4, 8, and 37 days respectively. Graft infection by HBV was accompanied by significant liver injury in six allografts in five recipients. In particular, there was a striking morphological appearance in five infected livers in which the hepatocytes became progressively enlarged and distorted as they accumulated huge amounts of hepatitis B surface and core antigens (HBsAg, HBcAg). These features were accompanied by pericellular fibrosis and cholestasis but little associated inflammation. This syndrome carried a poor prognosis. A gradual progression to cirrhosis occurred in one additional liver. Finally, recurrent HBV infection was a principal or a contributing factor in all deaths. The presence of HBcAg and inflammation in he native liver increased the risk of HBV induced tissue damaged in the graft whereas HDV infection in the host liver seemed to reduce the risk of significant HBV induced tissue damage in the allograft. These data suggest that post transplant HBV infection is accompanied by a variety of changes in the liver allograft, some of which are unique to the transplanted liver and may result in impaired allograft function.

A new approach for assessing the dietary exposure to food additives

By analyzing composite samples of brand name foods, a new method called the Dietary Exposure Assessment Method (DEAM), if found to be feasible, may provide useful estimates of daily intake of food additives for major portions of the U.S. population.

Detection of estrogen receptor in paraffin-embedded sections of breast carcinoma by immunohistochemistry and in situ hybridization

Biopsy specimens of small breast carcinomas are often insufficient for both diagnosis and the biochemical determination of estrogen receptor (ER) protein. Recent reports from various laboratories have shown the utility of immunohistochemical detection of ER protein in paraffin-embedded tissue sections. We used immunohistochemical (IHC) staining with the Abbott ER antibody (H222) and in situ hybridization (ISH) analysis with a 35S-labeled and a biotinylated oligonucleotide probe to detect ER protein and messenger RNA (mRNA) in tissue sections of 53 breast carcinomas. The dextran-coated charcoal (DCC) assay of these same cases revealed positive receptor levels in 31 of 53 cases, whereas the IHC method was positive in 33 of 53 cases. ISH for detection of ER mRNA was more sensitive than IHC or the biochemical assay for estrogen binding proteins, as the isotopic probe detected ER mRNA in 47 of 53 cases, whereas the biotinylated probe detected ER mRNA in 46 of 53 cases. These results indicate that ER protein can be readily detected in enzyme-treated paraffin tissue sections and that the IHC detection of ER protein correlates highly with the DCC assay. ISH with isotopic and biotinylated probes detects ER mRNA in most cases found to be positive for ER protein and also in many cases without detectable ER protein. Although detection of ER protein in paraffin sections correlates highly with the biochemical assay in this report and in other reported studies, the clinical significance of increased sensitivity by ISH is unknown and must await clinical correlative follow-up studies.

Crohn's-like lymphoid reaction and colorectal carcinoma: a potential histologic prognosticator

A distinctive Crohn's disease-like reaction (CLR) consisting of discrete lymphoid aggregates, some with germinal centers, and surrounding stellate fibrosis is commonly found around colorectal adenocarcinomas in the absence of clinical or pathologic evidence of prior Crohn's disease. Most lymphoid aggregates are located one or more millimeters beyond the advancing tumor fronts, mainly in muscularis propria and pericolic adipose tissue. The intensity of this reaction was graded as absent, mild, or intense for 100 consecutive colorectal carcinomas. These tumors also were evaluated for invasion beyond muscularis propria, lymphoid infiltrates at the tumor margin, and nodal metastases. The degree of CLR was correlated with survival. Results indicated that CLR is more likely to occur in transmurally invasive carcinomas than in those confined to the colonic wall, especially in the right side. An intense CLR is associated with an intense lymphoid infiltrate at the tumor edge, a lower incidence of nodal metastases, and a statistically significant increase in 10-yr survival. These results suggest that the Crohn's-like reaction around colorectal carcinomas may be a favorable host response, similar to lymphocytic infiltrates at the advancing tumor edge. Analysis of more cases should clarify whether this CLR is independent of other variables.

Pneumonia associated with infection with pneumocystis, respiratory syncytial virus, chlamydia, mycoplasma, and cytomegalovirus in children in Papua New Guinea

Paired serum samples were collected from 94 children with pneumonia admitted to Goroka Hospital, Papua New Guinea. All but three of the children were aged 1-24 months. Only nine children were malnourished, with weight for age less than 70% of the Harvard median (three had weight for age less than 60% of the Harvard median). Pneumocystis carinii antigen was detected in the serum of 23 children. Twenty two children had serological evidence of recent infection with respiratory syncytial virus. Five children were probably infected with Chlamydia trachomatis at the time of the study, and there was less convincing serological evidence of current infection in a further 11 children. Five children showed a fourfold rise in antibody to Mycoplasma pneumoniae. Although only one child showed a fourfold rise in antibody to cytomegalovirus, 86 children had this antibody. No child showed a fourfold rise in antibody to Ureaplasma urealyticum or Legionella pneumophila. P carinii, respiratory syncytial virus, C trachomatis, M pneumoniae, and cytomegalovirus may be important causes of pneumonia in children in developing countries.

Morton's neuroma: a microscopic evaluation

Microscopic evaluation of the interdigital neuroma is described in 24 nerves which were evaluated at six cross-section areas for size of the nerve and width of the perineural along with the fascicle diameter and the size and number of blood vessels inside each fascicle. A relationship was noted between the level of the distal edge of the intermetatarsal ligament. Cross-section that was taken at that area showed changes distally in nerve diameter, fascicle number and size, blood vessel number and size, and perineural width. These changes are consistent with the interdigital neuroma as an entrapment condition.

Chlorhexidine as an effective agent against Chlamydia trachomatis in vitro and in vivo

In a small field trial, chlorhexidine (50 micrograms/ml) was as effective against clinical trachoma as topical tetracyclines or oral co-trimoxazole; in vitro, 2.5 micrograms/ml was chlamydicidal.