"Put the what, where? Cut here?!" challenges to coordinating attention in robot-assisted surgery: a microanalytic pilot study

INTRODUCTION

During robot-assisted surgery (RAS), changes to the operating room configuration pose challenges to communication by limiting team members' ability to see one another or use gesture. Referencing (the act of pointing out an object or area in order to coordinate action around it), may be susceptible to miscommunication due to these constraints.

OBJECTIVES

Explore the use of microanalysis to describe and evaluate communicative efficiency in RAS through examination of referencing in surgical tasks.

METHODS

All communications during ten robot-assisted pelvic surgeries (radical cystectomies and prostatectomies) were fully transcribed. Forty-six referencing events were identified within these and subjected to a process of microanalysis. Microanalysis employs detailed transcription of speech and gesture along with their relative timing/sequencing to describe and analyse interactions. A descriptive taxonomy for referencing strategies was developed with categories including references reliant exclusively on speech (anatomic terms/directional language and context dependent words (CD)); references reliant exclusively on gesture or available aspects of the environment (point/show, camera focus/movement in the visual field and functional movement); and references reliant on the integrated use of speech and gesture/environmental support (integrated communication (IC)). Frequency of utilisation and number/percent 'miscommunication', were collated within each category when miscommunication was defined as any reference met with incorrect or no identification of the target.

RESULTS

IC and CD were the most frequently used strategies (45% and 26%, respectively, p≤0.01). Miscommunication was encountered in 22% of references. The use of IC resulted in the fewest miscommunications, while CD was associated with the most miscommunications (42%). Microanalysis provided insight into the causes and nature of successful referencing and miscommunication.

CONCLUSIONS

In RAS, surgeons complete referencing tasks in a variety of ways. IC may provide an effective means of referencing, while other strategies may not be adequately supported by the environment.

Defining "early dementia" and monitoring intervention: what measures are useful in family caregiving?

Measures of cognition are often used to define and measure the progress of dementia and outcomes of intervention. This paper examines whether measures of psychosocial disability used with those of cognition are more useful than measures of cognition alone, particularly in early dementia. A measure of cognition and two instruments of caregiver burden, used as routine clinical outcome measures of three types of Old Age Psychiatry dementia services, were examined. All cases with dementia in a memory clinic (MC; n = 149), a community mental health service for older people (CMHT; n = 120) and a specialist dementia day hospital (DH; n = 118), in one NHS district were followed up at 12 months. Measures of cognition (MMSE), behaviour, caregiver coping (Problem Checklist; PC) and caregiver mood (Hospital Anxiety and Depression Scale; HAD) were taken at baseline (MC, n = 48; CMHT, n = 113; DH, n = 55) and at follow-up (MC, n = 35; CMHT, n = 34; DH, n = 23). At baseline, all three groups had an average MMSE score of "mild impairment" but measures of behaviour and caregiver burden showed subtle between-group differences. At the 12-month follow-up, cognition remained stable in all groups, but the frequency of day-to-day problems increased and caregiver mood deteriorated in families receiving DH support. The use of psychosocial measures of disability in conjunction with those of cognition, are important in the definition and longitudinal measurement of intervention and support in early dementia.

Is transcutaneous electrical nerve stimulation an effective analgesia during colonoscopy?

OBJECTIVES

To evaluate the efficacy of transcutaneous electrical nerve stimulation (TENS) as analgesia during colonoscopy.

DESIGN

In a randomised controlled trial, patients undergoing diagnostic colonoscopy were assigned to one of three groups: standard medication only (midazolam); active TENS plus standard medication; or non-functioning TENS and standard medication. Efficacy of TENS was determined using numerical rating scores for pain and the post-procedural evaluation questionnaire.

SETTING

Patients undergoing diagnostic colonoscopy in a teaching hospital.

MAIN OUTCOME

There was no statistically significant differences between the three groups. However in the active TENS group there was a greater variation in "physical discomfort" and "psychological distress", suggesting TENS may be effective in subgroup of patients.

How much gin in the tonic? The problems of writing a provincial medical history,

This paper describes the problems and resources involved in writing a Canadian provincial medical history, (Manitoba Medicine: A Brief History). The first decision was whether it should be a scholarly or a popular history; The authors' background, and the realities of publishing dictated the latter. Resources available were local and easily accessible: archives and records, the Manitoba medical journals, a series of local medical journals (almost continuous for a century), and the Manitoba medical biographies, books variable in length, and content, but relating to a wide variety of physicians. Such a paper leads to a question- "Is local history merely trivial?" The answer to such a question is "no."

Arrowroot as a treatment for diarrhoea in irritable bowel syndrome patients: a pilot study

OBJECTIVES

Arrowroot is an old-fashioned remedy for diarrhoea, but no clinical studies have been done to evaluate its effectiveness. The aim of this pilot study was to assess its efficacy as a treatment for diarrhoea in 11 patients, all of whom had irritable bowel syndrome with diarrhoea as a feature.

METHODS

The patients were interviewed and a questionnaire completed on entry into the trial. They then took 10 mL arrowroot powder three times a day for one month and discontinued the treatment for the subsequent month. Questionnaires were completed after one month on treatment and at the end of the trial after one month off treatment.

RESULTS

Arrowroot reduced diarrhoea and had a long-term effect on constipation. It also eased abdominal pain.

CONCLUSION

Arrowroot is an effective treatment for diarrhoea. Its action could be explained by several theories which relate to an increase in faecal bulk and thus a more efficient bowel action. The number of patients was small, and further studies are needed to substantiate preliminary results.

The effects of migration on ulcerative colitis: a three-year prospective study among Europeans and first- and second- generation South Asians in Leicester (1991-1994)

OBJECTIVE

Our aim was to measure prospectively the incidence of ulcerative colitis in Leicester City and to compare this with a previous retrospective study in the same area. We also sought to compare the incidence and disease extent in the European community with that of the South Asian community and to compare the disease extent between first- and second-generation South Asian migrants.

METHODS

A 3-yr prospective study of ulcerative colitis in the city of Leicester took place from October 1, 1991 to September 30, 1994 and included all cases resident in Leicester City and diagnosed as having ulcerative colitis, regardless of the extent and severity of the disease.

RESULTS

Extensive colitis was commoner in second-generation migrants than in the first generation (chi2 = 4.3, p = 0.04) and was comparable to the European community. The annual average incidence of ulcerative colitis was 9.1/10(5) population/yr (95% confidence interval [CI] 7.1-11.3), which is similar to the previous retrospective study. However, the annual average incidence of ulcerative colitis in the European population was 7.0/10(5) population/yr (95% CI 5-9.5), whereas that of the South Asian population was 17.2/10(5) population/yr (95% CI 11.8-24.3), confirming that the risk of ulcerative colitis in this particular community is exceptionally high.

CONCLUSIONS

These early results suggest that the disease pattern follows that of the indigenous population after only one generation and requires monitoring over the next decade. The incidence of ulcerative colitis in the South Asian population is high and continuing to rise.

The effects of migration on ulcerative colitis: a three-year prospective study among Europeans and first- and second- generation South Asians in Leicester (1991-1994)

OBJECTIVE

Our aim was to measure prospectively the incidence of ulcerative colitis in Leicester City and to compare this with a previous retrospective study in the same area. We also sought to compare the incidence and disease extent in the European community with that of the South Asian community and to compare the disease extent between first- and second-generation South Asian migrants.

METHODS

A 3-yr prospective study of ulcerative colitis in the city of Leicester took place from October 1, 1991 to September 30, 1994 and included all cases resident in Leicester City and diagnosed as having ulcerative colitis, regardless of the extent and severity of the disease.

RESULTS

Extensive colitis was commoner in second-generation migrants than in the first generation (chi2 = 4.3, p = 0.04) and was comparable to the European community. The annual average incidence of ulcerative colitis was 9.1/10(5) population/yr (95% confidence interval [CI] 7.1-11.3), which is similar to the previous retrospective study. However, the annual average incidence of ulcerative colitis in the European population was 7.0/10(5) population/yr (95% CI 5-9.5), whereas that of the South Asian population was 17.2/10(5) population/yr (95% CI 11.8-24.3), confirming that the risk of ulcerative colitis in this particular community is exceptionally high.

CONCLUSIONS

These early results suggest that the disease pattern follows that of the indigenous population after only one generation and requires monitoring over the next decade. The incidence of ulcerative colitis in the South Asian population is high and continuing to rise.

Screening for osteoporosis in Crohn's disease. A detailed evaluation of calcaneal ultrasound

OBJECTIVES

To compare calcaneal broadband ultrasonic attenuation (BUA) and velocity of sound (VOS) in patients with Crohn's disease with an age-matched control population. The validity of BUA as a screening tool for osteoporosis was evaluated and the relationship between BUA and previous fracture studied.

DESIGN

Cross-sectional study.

BACKGROUND

Since patients with Crohn's disease are at risk of osteoporosis and premature fracture, routine assessment of bone mineral density (BMD) is recommended. Quantitative ultrasound of the calcaneum is an inexpensive and radiation-free means of assessing bone density which also provides information on bone microstructure.

METHODS

BUA (dB/MHz) and VOS (m/s) were measured at the calcaneum (CUBAclinical, McCue Ultrasonics, Winchester, UK) and compared with bone mineral density at the hip and lumbar spine measured by dual-energy X-ray absorptiometry (DEXA); 100 patients (42 men) with Crohn's disease and 52 age-matched healthy controls (23 men) were studied.

RESULTS

BUA was significantly reduced in patients with Crohn's disease compared with age-matched controls [76.53 dB/MHz (+/-17.3) vs 87.29 dB/MHz (+/-17.9), difference in means = 10.76, 95% CI -16.67, -4.85, P = 0.0004] and was significantly associated with BMD at the spine (r = 0.49, 95% CI 0.32, 0.63, P< 0.0001) and femoral neck (r = 0.54, 95% CI 0.38, 0.67, P < 0.0001). In the diagnosis of osteoporosis (t score <-2.5) BUA had a sensitivity of 66.7% at the femoral neck, with a specificity of 85.6%; sensitivity of BUA at the spine was 75% with specificity 89%.

CONCLUSION

Patients with Crohn's disease have reduced BUA compared with an age-matched control population. Calcaneal BUA is significantly associated with BMD at the hip and spine but the correlation is insufficient to recommend ultrasound as a screening tool for DEXA.

The role of acupuncture in the treatment of irritable bowel syndrome: a pilot study

BACKGROUND/AIMS

The aim of this pilot study was to investigate the potential value of acupuncture in the treatment of irritable bowel syndrome (IBS).

METHODOLOGY

The study was an open design study of 7 patients with established irritable bowel syndrome in which assessment was by a diary card.

RESULTS

The results showed a significant improvement both in general well-being and in symptoms of bloating.

CONCLUSIONS

Acupuncture seems to be effective in the treatment of irritable bowel syndrome and merits further study.

Ability of aberrant crypt foci characteristics to predict colonic tumor incidence in rats fed cholic acid

Aberrant crypt foci (ACF) are putative preneoplastic lesions of colon cancer which are being utilized currently as a biological end point to evaluate the induction and modulation of colon carcinogenesis. In several previous short-term studies, the unexpected reduction of ACF by the reported colonic tumor promoter cholic acid (CHA) emphasized the need for a systematic evaluation of the growth of ACF in response to a tumor promoter. The present study was conducted to determine if any characteristic(s) of ACF at various early stages of carcinogenesis would predict resulting tumor incidence in rats fed CHA. Male Sprague-Dawley rats received two injections of azoxymethane (20 mg/kg) and were fed either the AIN-76 diet or AIN-76 plus 0.2% CHA. The number, crypt multiplicity (number of crypts/focus), and size (area) of ACF were measured after 2, 8, 14, and 18 weeks in 5 rats/group. The number of ACF was lower (P < 0.033) in animals fed CHA at all time points. Average crypt multiplicity of ACF was greater (P = 0.045) from CHA-fed animals after 8 weeks compared to animals fed the AIN-76 diet. The average size of ACF was smaller in CHA-fed animals after 2 weeks and then tended to be larger than the sizes of the ACF from animals fed the AIN-76 diet. All remaining animals were killed after 18 weeks. Tumor incidence was higher (P < 0.001) in the CHA-fed group (63.2%) compared to the control diet group (29.4%). CHA-fed rats also had a higher number of tumors/tumor-bearing rat compared to control diet rats (1.96 versus 1.13). The main finding of this study is that the number of ACF at early time points did not predict tumor incidence. Crypt multiplicity was a consistent predictor of tumor outcome and should be measured in future studies using ACF as a biological end point. The CHA diet appears to provide a unique tumor-modulating environment that selectively enhances the growth of a smaller number of ACF leading to an increased number of tumors compared to a control diet. The mechanism(s) by which CHA mediates this effect warrants further investigation.

Will a tumor metastasize? Quantitate, semi-quantitate or pseudo-quantitate? A brief review of the microscopic prediction of tumor metastasis

This review examines ways in which histopathologists can attempt to predict whether a neoplasm will metastasize by microscopic examination of surgically removed samples of human neoplasms. These include qualitative description, semi-quantitative analysis of differentiation and proliferation, or of the nature of the edge of the neoplasm, and quantitative analysis of mitotic counts. More recently measurement of DNA content, analysis of DNA turnover, measurement of proliferation antigens, measurement of nucleolar organizing areas, counting nucleoli, morphometry of nuclei and identification of genetic change have become possible. There is no test capable of uniform accurate prediction of prognosis. In certain types of neoplasms in individual sites useful prognostic information can be obtained either by rigorous semi-quantitative microscopic analysis or by quantitative microscopical analysis. There is still doubt as to whether newer quantitative techniques will perform uniformly better than older semi-quantitative techniques. The simple subjective statement "high-grade malignancy, average malignancy, low malignancy" is better than elaborate non-reproducible pseudo-quantitation.

"Not on the outward appearance .... but on the heart." Matthew Baillie and cardiology

The work of Matthew Baillie (1761-1823), pathologist and physician, is presented with particular relation to the cardiovascular system. Baillie wrote the first systematic textbook of morbid anatomy in the English (or any other) language, and commissioned a book of elegant and accurate illustrations by William Clift (1775-1849). Baillie laid down the anatomical groundwork on which the subsequent generation of physicians built an accurate knowledge of cardiovascular disease. His textbook was widely translated, and influenced medical students and physicians over the first half of the 19th century. His influence on morbid anatomy was similar to that of Vesalius on the science of normal anatomy.

How malignant is malignant? A brief review of the microscopic assessment of human neoplasms, and the prediction of whether they will metastasize and kill

This review examines ways in which histopathologists can attempt to predict the degree of malignancy from the microscopic examination of surgically removed samples of human neoplasms. These include mitotic counts, measurement of DNA content, analysis of DNA turnover, measurement of proliferation antigens, measurement of nucleolar organizing areas, counting nucleoli, morphometry of nuclei, identification of genetic change, measurement of lysis of basement membrane, and measurement of invasion in vitro. The latter two are not currently of practical value. Of the rest none is uniformly capable of predicting the degree of malignancy of a human neoplasm. After further refinement and control measurement of several such parameters may however contribute more to the prediction of malignancy than present subjective assessments.

Neoplastic invasion in experimental carcinoma of the colon: abnormal differentiation and release of mucus

Carcinomas of the colon were induced in F344 rats with dimethylhydrazine (20 mg/kg for 12 weeks). The invasive edges of the lesions were examined with the electron microscope. As in human colorectal cancer, the invasive edges show neoplastic cells with abnormal differentiation of apical cytoplasmic rootlets and processes at the basal or invasive edge of the cell, 'apical reversal'. Mucous carcinoma cells release material into the interstitial connective tissue matrix. The features may contribute to the complex phenomenon of neoplastic invasion.

Morphogenesis as a parallel of invasion: the epithelial-mesenchymal boundary and basal lamina in foetal rat colon

In order to determine whether neoplastic invasion, as it occurs in colonic carcinoma, represents a recapitulation of embryonic events, the development of the crypts and basal lamina of the rat colon was examined in foetuses between 16 and 21 days gestation by light and transmission electron microscopy, autoradiography and morphometric techniques. The thickness of the basal lamina increased from days 16 to 18 of gestation. On days 19 and 20 the basal lamina was found to be significantly thicker in the intercryptal areas than at the base of the crypt. This difference disappeared at 21 days gestation. It was also demonstrated that cell migration and renewal occur in the same manner in the foetal colon as in the adult colon. These features do not resemble closely those seen in neoplastic invasion.

Mechanisms of invasion and lymphatic penetration in human colorectal cancer

The invasive areas in 24 unselected human colorectal cancers were examined by light and electron microscopy and it was shown that the invasive process involves tubes of cells rather than single cells, that degenerative changes take place in specialized cells ahead of the invasive cancer cells and that the endothelium of the lymphatic vessels disintegrates, leaving gaps in the endothelial lining.

A morphometric study of invasion and metastasis in human colorectal carcinoma

The cell nuclei within primary and nodal secondaries of colorectal carcinomas were analysed morphometrically in order to identify a primary subpopulation with similar characteristics to cells involved in lymphatic metastasis. No significant difference in nuclear area was seen between cell populations of the primary and secondary. However, a regional variation in mean nuclear area was present, suggesting a relationship between cells at the invasion front and in early nodal metastasis. This subpopulation differed from the cell populations of the primary and more advanced secondaries. These results are consistent with the existence of a morphometrically identifiable metastatic subpopulation within the invasion front of colorectal carcinoma.

Lymphatic metastasis and its treatment

The treatment of lymphatic metastasis depends on an understanding of its basic biology. We are still uncertain as to how human cancer cells enter lymphatic vessels and as to what reactions if any in the draining lymph node inhibit metastasis. We are uncertain as to whether lymphatic metastasis is an indicator or a governor of rapid dissemination, and poor prognosis. We are uncertain as to whether it is worth attempting to treat lymphatic metastases by means supplementary to those used in treating systemic tumour dissemination. It may be possible to obtain local cure of a local lesion by local lymphatic therapy and to concentrate therapy locally by intralymphatic infusion of a chemotherapeutic agent or encapsulation in liposomes. This is at best accessory to obtaining systemic cure of systemically disseminated neoplasm. Optimal results could be expected from appropriate combinations of local and systemic immunotherapy, chemotherapy and radiotherapy, after appropriate surgical reduction in tumour bulk.

Heterogeneity in a colonic carcinoid tumor

This report describes a colonic carcinoid tumor in which three, and possibly four, distinct cell types are distinguishable on the basis of their ultrastructure and granule morphology. These cell types closely resemble the normal endocrine cells of the large bowel, both in appearances and in relative frequency. The mixed composition of this tumor may have arisen either by parallel differentiation of distinct cell types, or by sequential maturation of one cell type.

Isolated granulocytic sarcoma: report of a case and review of the literature

Granulocytic sarcoma (GS) is an extramedullary tumor composed of granulocytic precursor cells. The tumor usually develops during the course of myelogenous leukemia or myeloproliferative disorders and may represent the initial manifestation of leukemia. Rarely, GS is recognized as an isolated tumor without any evidence of leukemia. However, in such cases, leukemia generally develops within 1 to 2 years of the diagnosis of GS. We are reporting a case of a 45-year-old woman who was diagnosed as having an isolated GS of the right breast in August 1980. She was treated with a partial mastectomy followed by 1 year of combination chemotherapy as used in the cases of acute myeloblastic leukemia and has remained free of disease to the present time. That is, she has not developed leukemia or recurrence of GS for 64 months. Based on this experience and on the review of the literature, we recommend that all cases of GS be treated with combination chemotherapy as in cases of acute myeloblastic leukemias.

The invasive edge: invasion in colorectal cancer

Primary human colorectal carcinomas which had already metastasized to the draining lymph nodes have been studied by transmission electron microscopy and tissue culture. The invasive edges were identified by examining mirror-image blocks for light and electron microscopy. In the invasive edge there are single cells and small clusters of cells which have ultrastructural features suggestive of active cell movement; clusters of cells are found in the lymphatic trunks and in the subcapsular sinus of draining lymph nodes. Small clusters of cells survive in short-term culture; some of these cells are actively motile. These findings support the view that there is a sub-population of motile and invasive cells at the edge of human colorectal cancers.

Primary lymphoma of the central nervous system: Manitoba experience and literature review

We describe eight cases of primary cerebral lymphoma seen in Manitoba from 1980 to 1985. The clinical presentation is similar to other primary brain tumors. The diagnosis should be considered when single or multiple, often deep lesions, show dense enhancement on computerized tomographic (CT) scan, but are avascular at angiography. These tumors are histologically indistinguishable from non-Hodgkins lymphomas arising outside the CNS. The prognosis is poor. However, radiotherapy with or without surgery may offer significant palliation. Although there is no consensus on the value of chemotherapy, corticosteroids alone or multiagent chemotherapy have shown promise in a few cases. For these reasons, histologic diagnosis should be sought in all cases and surgery, radiotherapy, and chemotherapy should be considered, as prolonged survival is possible.

Lymph node metastasis and cell movement: ultrastructural studies on the rat 13762 mammary carcinoma and Walker carcinoma

The aim of this study was to determine whether tumor cells move actively through the linings of lymph node sinuses. Using 13762 carcinoma in F344 rats, and Walker carcinoma in Wistar rats, 20 X 10(6) tumor cells were injected into the footpad, and the ipsilateral popliteal lymph node examined by transmission electron microscopy. The same tumors were examined by making standard cell spots on plastic or glass surfaces, and examining these by phase and reflection contrast microscopy, fluorescent microscopy after anti-actin and phallacidin staining and transmission electron microscopy. The 13762 cells do not migrate through the lining of the lymph node sinusoid, nor move actively in vitro. Ultrastructural appearances of the Walker rat carcinoma cells suggest that they move actively through the sinus lining. After 24 h in vitro the Walker rat carcinoma cells in the centre of the spot are adherent to the surface. There is some movement of the edge of the sheet, and individual tumor cells at the edge of the sheet move actively and independently. We conclude that the Walker rat carcinoma invades the lining of the lymph node sinusoid by active cell movement, and the 13762 carcinoma does not.

The myths and realities of civil defence

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Experimental lymphatic metastasis

A model of lymphatic metastasis of cancer has been established by injecting tumour cells into the rat footpad and examining the draining popliteal lymph node. The node can probably destroy only a few tumour cells; thereafter metastasis is progressive and lethal. The tumour cells penetrate the lymphatic endothelium, in the footpad either by moving singly between intact endothelial cells, by destroying the endothelium, or by passing in clumps between the endothelial cells. Tumour cells may then be obtained from the lymph by cannulation of the lymphatic trunk. These experiments pose the question: is local lymphatic chemotherapy useful in treating lymphatic metastasis?

Indomethacin treatment in small versus large premature infants with ductus arteriosus. Comparison of plasma indomethacin concentration and clinical response

An analysis of clinical response and plasma indomethacin concentration was performed on 10 small (less than or equal to 1000 g) and 12 large (greater than 1000 g) premature infants who had symptomatic ductus arteriosus and required intravenous indomethacin therapy (0.3 mg/kg per day). The postnatal age, daily fluid intake, and cardiopulmonary status of the two groups at time of study were comparable, The small premature infants had a significantly lower peak plasma indomethacin concentration and lower concentration in the first four hours after infusion, and lower plasma concentration X time integral than that of the larger premature infants. There was a significant difference between the groups in proportion of response (2/10 vs 9/12) after one dose of indomethacin; this difference was not seen after two to three doses. The results of the study suggest that small premature infants do respond to indomethacin treatment, but compared to the larger infants may require repeated doses.

Invasion and metastasis

Malignant tumours cause sickness and death largely because they invade and metastasize. Such spread is made possible by many cellular properties, including the ability of neoplastic cells to move and to release degradative enzymes. These properties enable tumour cells to break free of the primary tumour, penetrate blood or lymphatic vessels and, after being transported to distant sites, pass out of the vessels to establish new tumours. Not all cells in a tumour, however, are able to metastasize, so the process tends to select for greater malignancy in the secondary tumour. The heterogeneity of tumours probably accounts for the difficulty of providing effective treatment, in that the various subpopulations of cells arising from each tumour vary in their responses to chemotherapeutic agents. We do not yet understand the process sufficiently to treat cancer patients by interfering selectively with the metastatic mechanisms.

Lymphatic metastasis; lymphangiochemotherapy of mammary cancer: ascitic form of rat mammary adenocarcinoma 13762

When 5 million cells of the ascitic form of the RMT 13762 are injected into syngeneic F344 rat footpads there is consistent metastasis to the popliteal node more rapidly than when the solid form is used. A greater number of tumor cells escapes from the footpad to the draining node via the afferent lymph than with the solid tumor. Local intralymphatic injection of 5FU produces cure or retardation of nodal metastasis in a significant number of animals (p less than 0.002).

Lymphatic metastasis

Lymphatic metastasis is an important mechanism in the spread of human cancer. During its course, tumor cells first penetrate the basement of membrane of the epithelium, in which they arise, and then the underlying connective tissue, carried partly by hydrostatic pressure. They enter the lymphatic partly by active movement, pass up the lymphatic trunk; they then settle and proliferate in the subcapsular sinus, penetrate its endothelium and proliferate and destroy the node. There are varied forms of immune response in the node and in human nodes often a complex fibrous and vascular response. The degree of lymphocytic response may be important for prognosis. The nodal reaction may be stimulated by release of antigens from the tumor. One of the most studied animal models of lymphatic metastasis is that which occurs in the politeal node after injection of tumor into the footpad. This model has been used to show that tumor cells enter lymphatics through gaps in endothelium, probably between endothelial cells, and that lymph nodes can destroy small numbers of tumor cells. Local immunotherapy and chemotherapy can sterilize a lymph node of tumor cells; the modes of treatment used have included intralymphatic injection and encapsulation of chemotherapeutic agents in liposomes. Prior radiotherapy may accelerate metastasis possibly by making tumor cells shed into lymphatic vessels. Lymph nodes are rather poor barriers to tumor cells. The prognostic significance of lymph node metastasis varies within tumor type; if hematogenous metastasis is early, then the presence of lymph node metastasis is of lesser prognostic significance. Lymph nodes can probably destroy only small numbers of tumor cells. Tumor cell heterogeneity is of importance in many aspects of metastasis; while clonal variation may be of importance in determining lymph node metastasis, it is not yet clear how important this is, nor whether specific clones metastasize specifically to lymph nodes. Lymphography is well established in diagnosis of lymphatic metastasis. A recent interesting development has been to inject antibodies labeled with a radioactive label, and image the label in lymph nodes with a gamma-camera. If anti-tumor antibodies are used in this way it may be possible to detect lymph node metastasis. Within the expanding field of tumor metastasis, lymphatic metastasis needs much more attention, particularly in relation to the diagnosis and treatment of the lymphatic spread of human cancer.

Grain dust and alveolar macrophages: an experimental study of the effects of grain dust on the mouse lung

Exposure of mice to grain dust in a dusting chamber for 2-80 days led to a pulmonary macrophage response but no interstitial pulmonary damage. The macrophages contained prominent paracrystalline cytoplasmic inclusions.

Improved lung compliance following indomethacin therapy in premature infants with persistent ductus arteriosus

In the course of a double-blind controlled study of intravenous indomethacin therapy in premature infants with patent ducts arteriosus (PDA), dynamic lung compliance (CL) was determined in 11 infants (six control, five indomethacin) who were not on assisted ventilation during the study period. The clinical, biochemical and laboratory data before the study were comparable between the groups. Following therapy with indomethacin there was a significant decrease in left atrial/aortic root ratio (LA/Ao), left ventricular end-diastolic dimension (LVEDD) on echocardiogram, and an increase in tidal volume (VT) and CL. In the control group, these variables did not change significantly. The improved lung compliance following early indomethacin closure of PDA may alter the clinical course and outcome of these premature infants.

Upper airways obstruction. Presentation with systemic hypertension

Of 14 patients whose final diagnosis was upper airways obstruction associated with heart failure, 3 presented with systemic hypertension (up to 200/100 mmHg). In 2 the hypertension was so severe that at first it had to be considered as a possible cause of the presenting symptoms. The subsequent history indicated that it was an effect of the upper airways obstruction with heart failure.

Lymphatic metastasis of mammary adenocarcinoma. An experimental study in the rat with a brief review of the literature

When 5 million cells of the solid form 13762 rat mammary carcinoma are implanted into the footpad of syngeneic rats there is consistent (approximately 100%) metastasis to the draining popliteal node and thence up the lymphatic chain to the lungs. With the transmission electron microscope tumor cells are seen to penetrate gaps in the lymphatic endothelium, probably but not certainly, between endothelial cells. There is neither widespread patency nor significant destruction of lymphatic endothelium. The tumor cells penetrate in groups and lie in the lymphatic in groups with some evidence of acinar differentiation. Tumor cells lodge in groups in the subcapsular sinus and progressively pass down the radial sinusoids and destroy the node; as they grow there is extensive differentiation into adenocarcinoma. The draining lymph obtained by cannulation does not contain an increase in total cells. A few tumor cells are present mostly in clumps. Recruitment is continuous but not progressively increasing. Any theories on neoplastic invasion and metastasis must take into consideration possible aggregation of some tumor cell types in groups. The literature on experimental lymphatic metastasis is reviewed briefly.

Intravenous indomethacin therapy in premature infants with persistent ductus arteriosus--a double-blind controlled study

A double-blind controlled trial of intravenous indomethacin therapy was performed using a group of 55 premature infants (27 placebo, 28 indomethacin) with a significant persistent ductus arteriosus. Indomethacin administration at a mean postnatal age of 8.9 days was followed by a significant effect on PDA in 89%; 75% of successes were attributable to indomethacin and 25% to spontaneous effects, an improvement by indomethacin of 86% in infants not undergoing spontaneous improvement. The short-term side effects of indomethacin were transient; urinary output and serum sodium concentration decreased and serum potassium concentration increased. Indomethacin administration was associated with a decreased need for assisted ventilation and a decreased need for surgical closure of PDA. There was no significant difference between the placebo and indomethacin groups in mortality and bronchopulmonary dysplasia morbidity. The infants who developed BPD had higher RDS scores and lower PO2 values, requiring higher FIO2s within four hours of birth than those who did not develop BPD, indicating a more severe underlying pulmonary disability present birth.

Sarcoid macrophage giant cells. Ultrastructure and lysozyme content

Examination of the sarcoid granuloma by electron microscopic and electron microscopic immunocytochemical techniques shows that the sarcoid macrophage giant cell is rich in lysozyme, present within the centre of the syncytium in dense granules approximately 200 nm in diameter. The ultrastructure of the syncytium is that of an actively secretory cell, suggesting that the sarcoid macrophage giant cell actively produces as well as stores lysozyme, rather than being a fusion product of mononuclear cells which produce lysozyme, or being a site of storage of ingested lysozyme.

Lymphatic metastasis: invasion of lymphatic vessels and efflux of tumour cells in the afferent popliteal lymph as seen in the Walker rat carcinoma

When twenty million Walker rat carcinoma cells are injected into the footpad of albino outbred rats, there is progressive metastasis to the draining popliteal and thence para-aortic lymph nodes. The lymphatic duct efferent from the footpad and afferent to the popliteal node has been cannulated; it has been shown that there is a continuous and progressively increasing output of tumour cells, small and large lymphocytes, macrophages and polymorphs from the footpad. About 20 per cent of the cells are tumour cells. The number of tumour cells in the popliteal and para-aortic nodes has been counted using a Coulter counter and subsequent differential counting of stained smears; the nodes contain a progressively increasing number of both tumour cells and lymphoreticular cells. The early accumulation of tumour cells in the para-aortic nodes makes it evident that tumour cells pass rapidly through the primary node. Examination of the simulated primary tumour by transmission electron microscopy suggests that tumour cells move actively toward lymphatics and protrude cytoplasmic processes through gaps in the endothelium. The endothelial cell then degenerates in close proximity to tumour cell processes. This leaves gaps through which tumour cells may pass and ultimately results in lymphatics with large defects in their walls.

Pharmacokinetics of intravenously administered indomethacin in premature infants

We studied the pharmacokinetics of indomethacin (0.3 mg/kg) given intravenously in 17 premature infants to promote closure of persistent ductus arteriosus. The decay of indomethacin generally showed an initial rapid distribution (alpha) phase followed by a slower elimination (beta) phase. The mean half-life of elimination (20.7 +/- 8 hours) was three times longer, and the mean clearance rate (13 +/0 9.5 ml/kg/hour) was seven times less than that reported in adults. The indomethacin clearance rate was linearly correlated with postnatal age (r = 0.71, P < 0.01). There was strong evidence of later re-entry of indomethacin into the plasma, suggesting that enterohepatic recirculation may be common in premature infants and may contribute to the relatively long half-life of elimination. Our data do not clarify the question of target concentration or minimal exposure time above which permanent closure may occur, but the group of infants who had permanent PDA closure after only one dose (8/17) had a significantly higher plasma indomethacin concentration time integral than the group (9/17) who needed more than one dose (P < 0.01). A 24-hour dosage interval was often sufficient when an iv indomethacin bolus of 0.3 mg/kg was used but, below the age of nonresponsiveness to indomethacin, a shorter interval may be preferable as postnatal age increases.

Lysozyme production by a granuloma in vivo: output in blood and lymph in relation to ultrastructure and immunochemistry

The output of lysozyme into the venous and lymphatic drainage of a B.C.G. experimental granuloma has been studied. There is a massive output of lysozyme by both routes maximal in the lymph at 28 days, and in the serum at 35 days after induction of the granuloma. There is no similar excretion of acid phosphatase. The lactic dehydrogenase level both in blood draining the granuloma and blood draining the normal limb is elevated but not in precise synchrony with lysozyme output. Macrophages in the granuloma show ultrastructural features suggestive of secretion of dense granules, by appearance of electron dense material in the Golgi zone, and condensation therefrom. Granules are discharged on to the surface of lipid droplets, presumably representing attempted phagocytosis, but are not discharged elsewhere on the cell surface. Granules are released by cell disintegration both of macrophages and polymorphs. Lysozyme was demonstrated immunocytochemically in macrophage granules. The macrophages in the granuloma are biosynthetically active as shown by uptake of tritiated tyrosine. The findings support the view that granulomas export lysozyme and that this is due partly to exocytosis of material by macrophages on to the surface of lipid globules and partly to cell disintegration.

Endocardial cushion defect associated with cor triatriatum sinistrum or supravalve mitral ring

Clinical and angiographic or autopsy data, or both, on three children with a subdivided left atrium (cor triatriatum) and an associated endocardial cushion defect are reviewed. (One child had ostium primum defect, and two had complete atrioventricular [A-V] canal.) A fourth patient demonstrates the difficulties in differentiating subdivided left atrium from supravalve mitral stenosis in the presence of an endocardial cushion defect. The clinical findings are greatly influenced by the endocardial cushion defect. A pressure gradient between the pulmonary wedge and (left or right) ventricular end-diastolic pressures in patients with an endocardial cushion defect indicates pulmonary venous obstruction and should alert one to the possibility of these combined lesions. The exact diagnosis is made with injections of angiographic contrast medium into the proximal and distal left atrial chambers, to documented the respective relations of the pulmonary veins, left atrial appendage and A-V valves to these atrial chambers. All three patients with an endocardial cushion defect and a subdivided left atrium had an associated patent ductus arteriosus. The common association of subdivided left atrium with intracardiac, pulmonary venous and aortic anomalies is again demonstrated.