Apparent Increase In Frequency Research Articles

Complications of Otitis Media and Sinusitis Caused by Streptococcus anginosus Group Organisms in Children.

The Streptococcus anginosus group (SAG, S. anginosus, S. intermedius and S. constellatus) are often associated with severe disease and abscess formation. In our institution, we observed an apparent increase in frequency of intraorbital and intracranial infections resulting from SAG at Texas Children's Hospital. We undertook a retrospective review to describe the frequency and clinical features of these infections. We reviewed the database of the microbiology laboratory at Texas Children's Hospital from 2011 to 2018 for SAG-positive cultures. Cases included were those associated with (1) either otitis media or sinusitis and (2) Pott's puffy tumor, orbital abscesses, mastoiditis, epidural abscesses, subdural empyema, brain parenchymal abscesses or dural enhancement by imaging. The number of overall diagnoses were determined using diagnostic codes and used to estimate the proportion of disease caused by SAG. Ninety-five cases were identified meeting inclusion criteria. The median age of patients was 11.4 years, and 75.8% were previously healthy. S. intermedius was most commonly isolated (80%) followed by S. constellatus (12.6%) and S. anginosus (7.4%); 50.5% of cases were polymicrobial. Among polymicrobial cases, Staphylococcus aureus was most frequently isolated. All patients underwent surgical intervention. 8.4% of patients experienced persistent neurologic deficits. We observed a significant increase in disease incidence during the study period; in addition, the overall proportion of all intracranial infections caused by SAG increased. Complications of otitis media and sinusitis caused by SAG are associated with substantial morbidity. These infections are becoming increasingly common at our center although the precise reason for this temporal trend is unclear.

Recent massive coral mortality events in the South China Sea: Was global warming and ENSO variability responsible?

The key to predicting the possible response(s) of coral reefs to hypothesized future global warming is the knowledge of their response(s) to previous extreme climatic events. We obtained 80 high-precision U/Th ages for 78 dead massive Porites colonies from the Nansha Islands, South China Sea, with an aim to understand the long-term history, frequency, timing and causes of local coral mortality. Our results reveal a number of significant episodes of coral mortality since 1860AD, with an apparent increase in frequency and severity since 1930AD, and more recently since 1970, especially when only synchronized mortality events found to have occurred on both reefs were compared. The synchronized mortality events centered around 1865–1875, 1895–1900, 1910–1920, 1930–1945, 1970–1985 and 1990–2005AD, which imply regional common causes, were found to correlate well with the warm phases of the El Niño Southern Oscillation (ENSO) (i.e. El Niño years, e.g. some recent ones during 1972–1973, 1982–1983, 1991–1994, 1997–1998AD) on inter-annual time scale, as well as with positive phases of the Pacific Decadal Oscillation (PDO) or its sharp phase transitions on inter-decadal time scale. Synchronized coral mortality was absent during prolonged negative PDO phases, e.g. during 1950–1970AD. Overall, the data shows that immediately before, and at the time of, modern local ecological monitoring, the region's coral communities had already experienced several recent episodes of stress. The increased frequency distribution of mortality ages since 1930AD and more recently since 1970AD appears to coincide with progressively warmer sea-surface temperatures, both regionally and globally. Our data highlight the vulnerability of local coral communities in the face of present and predicted future warming.

An Application of Reverse Quasi Steady State Approximation over SERCA

Many cell types encode signals in the frequency component of calcium oscillations. In non-excitable cells calcium oscillations are induced by calcium influx from inositol trisphosphate receptors (IP3R) or/and ryanodine receptors (RyR). The frequency of Calcium oscillations induced in such cases is primarily by the way intracellular stores like endoplasmic reticulum, sarco-endoplasmic reticulum are refilled. Sarco-endoplasmic reticulum calcium ATPase (SERCA) is the major pathway by which this refilling process is effected. Most of the mathematical models proposed thus far used Michaelis-Menten kinetics to formulate SERCA pump. In this paper more emphasis has been given over the mathematical formulation of SERCA pump. In particular reverse quasi steady-state approximation (rQSSA) is used to formulate SERCA pump. Comprehensive comparative analysis is performed with the previous SERCA pump formulation. An apparent increase in frequency and amplitude of calcium oscillation is observed. Keywords - SERCA, Michelis-Menten, rQSSA, Enzyme Kinetics.

Identification and Measurement of Summer Dormancy in Temperate Perennial Grasses

ABSTRACTThere is an apparent increase in frequency of prolonged droughts in regions with Mediterranean climates. This has rekindled interest in the summer dormancy trait for improving drought resistance of temperate perennial pasture grasses. In orchardgrass (Dactylis glomerata L.), tall fescue [Lolium arundinaceum (Schreb.) Darbysh.], and phalaris (Phalaris aquatica L.), identification of the three common drought resistance traits of vascular plants, dehydration avoidance (or delay), dehydration tolerance, and summer dormancy, is often confused. Summer dormancy, the least common of these traits, is found in cool‐season grasses from semiarid and arid Mediterranean climates and provides an enhanced level of drought resistance. It is best measured in field‐grown plants previously exposed to low winter temperatures and short photoperiods. Those perennial grasses not exhibiting summer dormancy survive drought by avoiding and/or tolerating dehydration and express this as a response to water deficit irrespective of the season. Here we review three summer water‐supply environments, full irrigation, midsummer storm, and summer drought, for their precision and repeatability in measuring dormancy. Full irrigation and midsummer storm can be recommended, but measurement of dormancy under prolonged drought caused inconsistencies.

Human Health in a Changing Climate: Past, Present, and Future

TM4-O-01 Session Title: Climate Change and Human Health Climate has changed more rapidly over the past decade or so than was foreseen in previous modelled forecasts. Some of the phenomena (eg, melting glaciers and changes to rainfall regimens) previously assumed to lie decades ahead now appear to be underway. The recent apparent increase in frequency and intensity of some extreme weather events portend significant risks to human well-being and accord with the expectation that climate will become. Interest in the relationship between climate and health has a long history. In the fifth century BC, Hippocrates related epidemics to seasonal weather changes. In 1877, severe drought affected India, China, and other areas, causing over 20 million estimated deaths from famine and disease. However, the health impacts of human-induced global climate change seem likely to occur on a different spatial scale and with different temporal dynamics from those of natural climate variability. This emerging “global” environmental hazard poses important conceptual and methodologic challenges to epidemiologists, in identifying, forecasting, and proposing ways of ameliorating the health risks of climate change. Recent evidence indicates that more variable with global warming. Such extreme events are illustrated by 1) Hurricane Katrina in 2005, which killed over 1000 people, displaced over a million people, and spread oil, toxins, and microorganisms throughout the U.S. Gulf Coast, and 2) the 2003 heat wave that killed 35,000 people in western Europe alone and caused severe economic losses. Other recent weather disasters (eg, floods in Central Europe in 2002 and 2005) and record high temperatures in many parts of the world (eg, severe heat waves in Australia in 2004 and 2005) may have incorporated an increasing influence of climate change. Further, other evidence indicates that the transmission of infectious diseases (eg, malaria, schistosomiasis, and Lyme disease) may have increased in some parts of the world in association with warming. While developed countries may find it difficult to cope with the impacts of occasional extreme manifestations of climate change, developing countries face more difficulties in defining, assessing and, in particular, adapting to these changes. In light of these emerging trends, more investment in research and policy development is needed in relation to both mitigation and adaptation. The former is essential to minimize future health (and other) impacts, and the latter is essential to reduce the risk of health impacts, which cannot be avoided in the near to medium term. To engage in this now-important topic area, epidemiologists will need to generate skills and methods in 1) interdisciplinary research (including in connection with some unfamiliar earth-system science topics); 2) assessing causal relationships within a system-change context; and 3) scenario-based risk assessment of future health risks. The formal evaluation of community-based adaptive (coping) strategies will also be important.

Species and Mating-Type Distribution of Tapesia yallundae and T. acuformis and Occurrence of Apothecia in the U.S. Pacific Northwest

ABSTRACT Eyespot of wheat is caused by the discomycete fungi Tapesia yallundae and T. acuformis. T. yallundae is considered the most important causal agent of the disease in this region but no apothecia of either species have been found in the U.S. Pacific Northwest (PNW). Two compatible isolates of T. yallundae from the PNW were used to inoculate a field plot in the fall of 1998 and apothecia developed in the spring and fall of 2000 on standing wheat stubble. In the spring of 2000, wheat stubble from eight naturally infected fields was examined for the presence of apothecia of T. yallundae and T. acuformis. Apothecia of T. acuformis were found in two fields but no apothecia of T. yallundae were found. This is the first report of apothecia of the eyespot pathogens occurring in the PNW. Species and mating-type distribution of T. yallundae and T. acuformis in the PNW were determined from 817 isolates collected from diseased wheat over 3 years at spatial scales ranging from within fields to across states. In all, 460 isolates were identified as T. yallundae and 357 isolates were identified as T. acuformis with MAT1-1/MAT1-2 ratios not significantly different from 1:1 based on chi(2) tests at most scales tested. The apparent increase in frequency of T. acuformis from previous surveys may indicate a shift in the predominant species causing eyespot. The occurrence of apothecia under field conditions, along with the widespread distribution of mating types of both species, suggests that sexual reproduction may be occurring in both species.

Attributable risk of H. pylori in peptic ulcer disease: does declining prevalence of infection in general population explain increasing frequency of non-H. pylori ulcers?

Recent reports in the United States have found that fewer peptic ulcers are due to Helicobacter pylori than previously believed. The aim of this study is to determine if the declining prevalence of H. pylori infection in the general population can account for the apparent increase in the frequency of non-H. pylori ulcers. A total of 396 patients with peptic ulcer or ulcer scar were enrolled in this study. The pre-1950 population consisted of 149 patients with gastric ulcers and with 44 duodenal ulcers. The post-1950 population consisted of 96 patients with gastric ulcers and 107 with duodenal ulcers. The frequency of H. pylori-negative gastric ulcers was 5.4% in patients born before 1950 and 4.2% in patients born after 1950, and the frequency of H. pylori-negative duodenal ulcers was 0% and 1.9%, respectively. There are no statistical differences between the two populations in gastric and duodenal ulcers. H. pylori seropositivity was 74.9% in asymptomatic volunteers born before 1950 and 20.7% in those born after 1950 (P < 0.01) in the general population. The attributable risk of H. pylori infection in peptic ulcer diseases was not affected by the prevalence of H. pylori infection in the general population in Japan. This suggests that the apparent increase in frequency of non-H. pylori ulcers in the United States is not simply due to the declining prevalence of infection. Other explanations for non-H. pylori ulcers should be sought.

Prophylactic Oophorectomy: Reducing the U.S. Death Rate from Epithelial Ovarian Cancer. A Continuing Debate

The Oncologist 1996;1:326-330 Correspondence: M. Steven Piver, M.D., Department of Gynecologic Oncology, Gilda Radner Familial Ovarian Cancer Registry, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA. Telephone: 716-845-3110; Fax: 716-845-7608. Received August 1, 1996; accepted for publication August 27, 1996. ©AlphaMed Press 1083-7159/96/$5.00/0 If instead of the title “Prophylactic Oophorectomy: Reducing the U.S. Death Rate from Epithelial Ovarian Cancer,” the title were “Drug X Reducing the U.S. Death Rate from Epithelial Ovarian Cancer,” there would be great media and medical attention worldwide to such a report. Correctly so. Regrettably, there probably is no new Drug X in the foreseeable future that will significantly reduce the death rate from ovarian cancer, be it Taxol®, taxotere, topotecan, gemcitabine, or liposomal doxorubicin—although each may result in significant responses and some prolongation of median survival. Epithelial ovarian cancer is a much more complex disease than anyone envisioned, when it was believed that extensive debulking surgery and the newest cytotoxic chemotherapy would radically reduce the death rate from ovarian cancer in the United States. Over 20 years after the first patient was treated with cisplatin for epithelial ovarian cancer, the annual death rate from ovarian cancer continued to increase. Just in the past decade, the number of women in the United States dying from ovarian cancer has increased 18% (Fig. 1) [1]. Although ovarian cancer is estimated to account for 26,700 cases and 14,800 deaths in 1996, it is a low-prevalence disease in comparison with breast cancer, which in 1996 is estimated to account for 185,700 cases and 44,560 deaths. Inexplicably, similar to breast cancer, the lifetime risk for ovarian cancer in the United States continues to increase. The most recent Surveillance, Epidemiology and End Results (SEER) calculations of lifetime risk for ovarian cancer are that 1 in 55 women will develop ovarian cancer over their lifetime, or 1.8%, up from the 1970 figures of 1 in 70, or 1.4% [2]. The 1.8% baseline lifetime risk for the general population is used to estimate the lifetime risk of known ovarian cancer risk factors (Table 1). Even utilizing what are now believed to be two of the most effective cytotoxic drugs against stage III and IV epithelial ovarian cancer, Taxol® and cisplatin, researchers reported that this resulted in an increase in the median disease-free survival of only five months, as compared with those women allocated to receive cisplatin and cyclophosphamide (median diseasefree survival of 18 and 12.9 months, respectively), felt then to be the standard therapy [3]. Patients treated with Taxol® and cisplatin survived a median of 14 months longer than those

Australian Case-Control Study of Adverse Reactions to Japanese Encephalitis Vaccine.

Background: Japanese encephalitis (JE) is widely distributed in Asia and is the world's most common aborviral encephalitis. An effective vaccine against JE has been used in Asia for decades without reports of serious adverse reactions. Since 1989, an apparent increase in frequency of allergic reactions to JE vaccine has been reported from a number of nonendemic countries, including Australia. The objective of this study was to evaluate possible risk factors for allergic reactions associated with Japanese encephalitis (JE) vaccine. Methods: A case-control study was carried out in Australia. Subjects were persons who had developed an allergic reaction (rash and/or edema) that had occurred within 1 week of a dose of Biken JE vaccine. All cases had been reported to the Australian Adverse Reactions Advisory Committee, and all could be accessed for purposes of this study. Three matched controls were recruited for each of five cases. Participants completed a questionnaire and had venous blood drawn. Results: Cases were significantly less likely than controls to give a history of contact with dogs (Fisher's exact test p =.03); were more likely than controls to have received other immunizations in the 1-9 days prior to, rather than on the same day, as the JE vaccine (chi-square test for independence p =.015); and were more likely than controls to have consumed more than usual quantities of alcohol in the 48 hours following the last dose of JE vaccine (Fisher's exact test p =.034). Conclusions: We recommend, where possible, that JE vaccine be administered concurrently with other vaccines, that recipients be advised to avoid more than usual alcohol intake after receiving JE vaccine, and that active surveillance of adverse events associated with JE vaccine be conducted.

A Population-Based Clinical Trial with the SPf66 Synthetic Plasmodium falciparum Malaria Vaccine in Venezuela

A phase III malaria vaccine trial in 13 villages in an endemic area, South Venezuela, compared incidence rates of Plasmodium falciparum and Plasmodium vivax infections in 1422 vaccinated and 938 nonvaccinated subjects over 18 months. The SPf66 vaccine was given in three doses, on days 0, 20, and 112. Vaccination was complete in 976 subjects (68.7%). Minor side effects requiring no treatment were reported by 123 (12.6%), with an apparent increase in frequency from the first to the third vaccine dose. No autoimmune evidence was observed in a sample of subjects. Antibodies against SPf66 were present at low titers in 24.7% of tested subjects before vaccination, increasing to 53.6% after the second dose and to 73.6% after the third dose; 26.4% of subjects initially seronegative never seroconverted. The SPf66 malaria vaccine showed a protective efficacy of 55% (95% confidence interval, 21%-75%) against P. falciparum and of 41% (19%-57%) against P. vivax malaria.

Low-Dose Aspirin Therapy for Chronic Stable Angina

To evaluate the efficacy of low-dose aspirin in the primary prevention of myocardial infarction among patients with chronic stable angina. A randomized, double-blind, trial. The study included 333 men with baseline chronic stable angina but with no previous history of myocardial infarction, stroke, or transient ischemic attack who were enrolled in the Physicians' Health Study, a trial of aspirin among 22,071 male physicians. Patients were randomly assigned to receive alternate-day aspirin therapy (325 mg) or placebo and were followed for an average of 60.2 months for the occurrence of myocardial infarction, stroke, or cardiovascular death. During follow-up, 27 patients had confirmed myocardial infarctions; 7 were among the 178 patients with chronic stable angina who received aspirin therapy and 20 were among the 155 patients who received placebo (relative risk, 0.30; 95% CI, 0.14 to 0.63; P = 0.003). While simultaneously controlling for other cardiovascular risk factors in a proportional hazards model, an overall 87% risk reduction was calculated (relative risk, 0.13; CI, 0.04 to 0.42; P less than 0.001). For the subgroup of patients with chronic stable angina but no previous coronary bypass surgery or coronary angioplasty, an almost identical reduction in the risk for myocardial infarction was found (relative risk, 0.14; CI, 0.04 to 0.56; P = 0.006). Of 13 strokes, 11 occurred in the aspirin group and 2 in the placebo group (relative risk, 5.4; CI, 1.3 to 22.1; P = 0.02). No stroke was fatal, but 4 produced some long-term impairment of function. One stroke, in the aspirin group, was hemorrhagic. Our data indicated that alternate-day aspirin therapy greatly reduced the risk for first myocardial infarction among patients with chronic stable angina, a group of patients at high risk for cardiovascular death (P less than 0.001). Although our results for stroke were based on small numbers, they suggested an apparent increase in frequency of stroke with aspirin therapy; this finding requires confirmation in randomized trials of adequate sample size.

Interaction of Granulocytopenia and Construction Activity as Risk Factors for Nosocomial Invasive Filamentous Fungal Disease in Patients with Hematologic Disorders

A clinicoepidemiologic study was undertaken to investigate an apparent increase in frequency of nosocomial invasive filamentous fungal disease (NIFFD) in adult patients with acute leukemia hospitalized during a period of hospital construction, and to determine if a relationship existed between the construction activity and the acquisition of NIFFD. The first study goal, to determine the incidence of NIFFD before and during construction, was approached by calculation of incidence rates of NIFFD in patients with acute leukemia, comparing 1982 and 1983 (a baseline period free of construction) to 1986 (a year when construction activity was at its peak). The second study goal, to identify risk factors for the development of NIFFD, was accomplished by reviewing the autopsy records of all patients with underlying hematologic disorders accompanied by granulocytopenia who died in our hospital from 1982 through 1986. Patients with and without autopsy evidence of NIFFD were then compared by univariate and multivariate (logistic regression) analysis to identify potential risk factors for the acquisition of NIFFD. The incidence of NIFFD in patients with acute leukemia hospitalized during the period of hospital construction was significantly increased when compared to a baseline period without construction (11 per 139 versus 4 per 333, p less than .001). Review of all granulocytopenic patients autopsied over the five-year interval 1982 through 1986 revealed duration of granulocytopenia and hospitalization during construction to be risk factors for NIFFD by univariate analysis (p less than .005). Logistic regression showed duration of granulocytopenia to be highly significant independent risk factor (p less than .01) and construction activity to be a probable independent risk factor (p = .09).(ABSTRACT TRUNCATED AT 250 WORDS)

Some endocrine changes associated with the post-partum period of the suckling beef cow.

Seven Hereford cows with single calves were bled by jugular venepuncture, daily from parturition until 63-79 days post partum; 6 of the cows were also bled through jugular cannulae every 15 min for 8 h every 10 days. The average post-partum interval to first oestrus was 59.8 +/- 3.7 days for 5 of the cows. In cows returning to oestrus, plasma concentrations of progesterone were low until 55.5 +/- 3.0 days post partum, rose to exceed 0.5 ng/ml plasma for 4.0 +/- 0.4 days, declined for 5.0 +/- 0.5 days and then rose again to normal luteal-phase levels. First oestrus preceded the initial rise in progesterone in 1 cow and followed it is 4. Ovarian palpation revealed considerable follicular development before the initial rise in progesterone, but no clearly discernable corpus luteum until normal luteal-phase progesterone levels were detected. Plasma concentrations of oestradiol-17 beta fell after parturition and, although very variable, showed no apparent trend thereafter. Plasma concentrations of LH varied in an episodic manner, with an apparent increase in frequency and magnitude of peaks up to 10-33 days before the first elevation in plasma progesterone. Subsequently there was little change, except for a decline in peak LH concentrations after the initial elevation in plasma progesterone.

Pituitary adenomas in childhood and adolescence.

This report describes a group of 25 children and adolescents with biopsy-proven pituitary adenomas. They were found in 33% of patients encountered in our recent study of 74 parasellar tumor detected in patients under 20 years old. Earlier detection accounts for this apparent increase in frequency. This interpretation is supported by the rarity of signs of intracranial hypertension at presentation, as well as decreased incidence and severity of visual failure. More than 70% of patients have evidence of pituitary hypersecretion at presentation. Increased awareness of these endocrinological signs as well as improved hormonal assays facilitate both diagnosis and management. Hypopituitarism is rare; the important exception is suppression of gonadotrophic function that is known to occur early in the natural history of intrasellar pituitary adenomas. The low incidence of suprasellar and extrasellar extension is documented by both radiographic and operative findings. Transsphenoidal resection was employed in 92% of patients, with an estimated total resection in 73% of cases. Follow-up studies show a high quality of survival; no patient has severe neurological deficit and less than half of them require replacement therapy. The recurrence rate is 8%. Our findings do not support a previous report that pituitary adenomas in this age group are frequently extrasellar and invasive.

Breast milk leukocytes

The apparent increase in frequency of neonatal necrotizing enterocolitis1 and the recognition that the gastrointestinal tract is often the portal of entry in neonatal sepsis2 has renewed interest in breast milk as a source of newborn immunity. Attention has recently focussed on milk leukocytes. The purpose of this commentary is to summarize the available information on this subject and to examine the implications that this knowledge may have on the possible use of human milk-feeding to protect the newborn from infection. Human colostrum and early milk contain 1 to 2 x 106 leukocytes; 80% to 90% of these are monocytic phagocytes and the remainder are lymphocytes.3,4

The Diagnosis and Management of Pulmonary Embolism and Infarction

Pulmonary embolism and infarction is a relatively common disorder of serious significance which is commonly mistaken for many other pulmonary conditions. Its recognition and treatment should be of great interest to all physicians, particularly those specializing in diseases of the chest. It should be recognized promptly to initiate treatment and to try to prevent recurrences. Incidence During recent years there has been a marked apparent increase in frequency which is probably due to an increased alertness of this condition on the part of physicians in general. It was formerly believed that pulmonary embolism and infarction was commonly seen only in patients who had recently undergone operation or delivery. Now we know that it is much more commonly encountered in the practice of internal medicine, particularly in patients with cardiovascular diseases. Although pulmonary embolism has always been common, previously It was diagnosed as all sorts of things, notably pneumonia and pleurisy, and was commonly unrecognized during life. However, during recent years we have come to appreciate its frequency and significance, and the diagnosis can be readily made if the condition is thought of. The incidence is variously reported and is found in about 14 per cent of all carefully performed autopsies.’ It appears sooner or later in a large percentage of cardiac patients, being found In 48 per cent of one series who died of congestive heart failure.2 Sixty per cent of all cases occur in medical patients and at least half of these are found In persons with heart disease. Only about 40 per cent occur in surgical and obstetrical patients.’ A representative figure for a general hospital Is about 0.6 per cent of all medical admissions and about 0.25 per cent of all surgical admissions.3 Pulmonary embolism and infarction account for 5 to 10 per cent of all post-operative deaths.2 Our experience with patients confined to bed because of pulmonary tuberculosis has shown that this is a relatively infrequent complication. The sex distribution is about evenly divided between the two sexes. Pulmonary embolism and Infarction occur much more commonly in older patients, but is a fairly frequent complication in middle-aged or young adults with heart failure. Eighty-five per cent of the cases occur In persons over 40, and at least half are over 50.� It is rare before the age of 20.

Multiple birth frequency according to parity and maternal age.

SUMMARYThe Author has examined the published statistics of multiple births in England and Wales 1938-45, in Italy 1948-49 and in New York 1936-37, to see to what extent the apparent increase in frequency of twin births as parity increases amongst mothers of a quinquennial age-group is exaggerated by the mere fact of grouping. He concludes that the effect of the 5 year grouping on the rates is small, and that the data from the three countries indicate that at certain ages the probability that a birth will be multiple tends to increase with the order of the birth.

TUMORS OF THE SPINAL CORD IN CHILDREN

The view that neoplasms of the spinal cord in children are rare is not supported by statistics. Forty years ago Schlesinger, 1 in a series of 251 tumors of the spinal cord disclosed at autopsy, found that 24 per cent were in children under 15 years of age. Stookey, in 165 cases in which the diagnosis was verified at the Neurological Institute between 1910 and 1926, found only 8 of the tumors in children under 12. However, it must be added that 2 of the 8 children were operated on before 1922, while in the remaining 6 the condition occurred during the next four years. The apparent increase in frequency is probably explained by the progress made during that period in the recognition of tumors of the spinal cord at this particular clinic. Unfortunately this progress has not obtained generally, as in many cases the lesions are still doubtless overlooked