THE DISTRIBUTION OF FRIEDL?NDER'S BACILLI OF DIFFERENT TYPES

In a study of the distribution of the specific types of Friedländer''s bacillus, it is shown that: (1) Of 80 strains 52 per cent belong to Type A, 15 per cent to Type B, 9 per cent to Type C, and 24 per cent to Group X. (2) Type A contains for the most part strains derived from diseases of man and more than 70 per cent are associated with pneumonia in man. (3) Type B includes the greatest number of strains from animal sources, while the heterogeneous strains comprising Group X come from the greatest variety of diseases. It was demonstrated that in a patient suffering with pneumonia due to Friedländer''s bacillus (Type A), a specific precipitin reaction of the urine occurred in the corresponding (Type A) immune serum. A study of the sugar fermentation reactions of Friedländer''s bacillus shows that (1) there is no correlation between serological type and fermentative activity; (2) the fermentation reactions are variable and therefore not reliable for distinguishing Friedländer''s bacillus from closely allied organisms; (3) the strains of Group X show the greatest variation in fermentation, and (4) of 15 strains unable to ferment lactose, 13 belong to Type A.     

THE INFLUENCE OF CHOLINE,CYSTINE, AND OF α-TOCOPHEROL UPON THE OCCURRENCE OF CEROID PIGMENT IN DIETARY CIRRHOSIS OF RATS

1. Five per cent l-cystine in a stock or low protein diet produces ceroid deposits in rat liver. This effect of l-cystine is much greater in low protein than in stock diets. 2. One per cent choline has an inhibiting effect on deposition of liver ceroid resulting from a low protein diet containing excess cystine. 3. The occurrence of ceroid pigment in the livers of rats on a low protein diet, with or without the addition of excess l-cystine, is transiently inhibited by the administration of α-tocopherol. Five per cent cod liver oil in the diet did not prevent this effect of α-tocopherol. 4. On low protein, vitamin E-deficient diets, there occurs after 4 months, a rapid and progressive weight loss. This does not happen when α-tocopherol is added to the diet.     

IMMUNOLOGICAL RELATIONSHIPS OF CELL CONSTITUENTS OF ENCAPSULATUS PNEUMONI? (FRIEDL?NDER'S BACILLUS)

1. The soluble specific substance of Friedländer''s bacillus is non-antigenic when dissociated from the cell. It is different for each type and it is highly reactive in the corresponding anti-S serum. 2. The nucleoprotein is antigenic, induces the species or protein antibody which reacts with capsule-free cells and protein derived from all types. Antiprotein sera do not react with either the encapsulated cell or the polysaccharide derived from it, and they offer no protection against infection. 3. Anti-R and antiprotein sera are identical in their behavior. 4. The carbohydrate of Friedländer''s bacillus is demonstrable in filtrates of actively growing cultures and in the blood and urine of infected animals. 5. The protein is demonstrable in filtrates of only old, disintegrating cultures.     

DOES THE INGESTION OF ALCOHOL INFLUENCE THE DEVELOPMENT OF ARTERIOSCLEROSIS IN FOWLS?

The effect of alcohol ingestion upon the development of naturally occurring and stilbestrol-induced arteriosclerosis was studied in the domestic fowl. In two experiments, a 15 per cent ethyl alcohol solution was used for drinking purposes, and in a third experiment wine containing 12 per cent of it was administered. The caloric intake of both food and alcohol was carefully controlled by pair-feeding, a glucose solution being used for drinking purposes to equalize the caloric intakes of the control birds with those of the alcohol-treated birds. A total of 224 cockrels was studied, and the period of observation for each experiment lasted 12 months. The degree of arteriosclerosis in the thoracic and abdominal aortas was determined in the gross and microscopically, and the degree of lipide infiltration was determined microscopically. The gross grading of arteriosclerotic lesions agreed closely with the microscopic analysis of intimal thickening and lipide infiltration of the arterial wall. The gross gradings were subjected to a critical statistical analysis which allowed precise statements to be made on the probability that a real effect would be overlooked. This analysis yielded no evidence that alcohol or the wine used had affected the degree of gross arteriosclerosis or lipide infiltration.     

A STUDY OF THE PROTEOLYTIC FERMENTS OF THE LARGE LYMPHOCYTES IN A CASE OF ACUTE LEUK?MIA

The leucocytes of the blood of normal individuals and of patients showing a marked polymorphonuclear leucocytosis contain enzymes capable of digesting coagulated blood serum in neutral, alkaline or acid solutions. The cells in pus that is composed principally of polymorphonuclear leucocytes and the leucocytes of the circulating blood in myelogeneous leukæmia contain similar proteolytic enzymes, which act best when the reaction is alkaline. The leucocytes of the circulating blood and of the enlarged lymph nodes from a case of large cell, acute, lymphatic leukæmia contain proteolytic enzymes that act qualitatively in much the same way as the leucocytes of pus and as the white corpuscles of the blood in myelogenous leukæmia. These large lymphocytes in acute lymphatic leukæmia can be differentiated biologically from the small lymphocytes in chronic lymphatic leukæmia which possess no proteolytic enzymes, and from the large endothelioid cells of the hyperplastic lymph glands which are proteolytic only in the presence of acid. These results seem to show that the large cells of the so-called acute lymphatic leukæmia are not true lymphocytes, but are nearly related to the granular myelocytes and should probably be considered as the forerunners to these cells.     

THE R?LE OF THE THEBESIAN VESSELS IN THE CIRCULATION OF THE HEART

In summary, evidence has been presented to show a direct connection other than through the capillaries between the coronary arteries and the chambers of the heart. This connection was shown by perfusion, injections and serial sections to be through the Thebesian veins. Communications between the larger coronary veins and the Thebesian veins were also demonstrated by the same methods. Serial sections through Thebesian veins have shown capillaries draining directly into them. Under certain conditions it has been shown that as much as 90 per cent of the arterial flow may escape via the Thebesian vessels. Lastly, in the event of gradual closure of the orifices of the coronary arteries, the Thebesian vessels can supply the heart muscle with sufficient blood to enable it to maintain an efficient circulation.     

THE RAT AS A CARRIER OF SPIROCH?TA ICTEROH?MORRHAGI?, THE CAUSATIVE AGENT OF WEIL'S DISEASE (SPIROCH?TOSIS ICTEROH?MORRHAGICA)

1. On the basis of these findings, we conclude that the extermination of rats and field mice is a highly important prophylactic measure against Weil''s disease. 2. The chemical composition of soil and water plays animportant part in the development of Spirochœta icterohœmorrhagiœ, and consequently in the spread of the disease of which it is the causative agent.     

THE USE OF THE FINAL HYDROGEN ION CONCENTRATION IN DIFFERENTIATION OF STREPTOCOCCUS H?MOLYTICUS OF HUMAN AND BOVINE TYPES

1. Under the conditions of these experiments, there appears to be a distinct and constant difference in the final hydrogen ion concentration of Streptococcus hæmolyticus from human and bovine sources. 2. Of 124 strains of Streptococcus hæmolyticus from known human origin, 116 reached a final hydrogen ion concentration of from pH 5.0 to 5.3. Only 8 reached a pH more acid than 5.0 and none more acid than pH 4.8. 3. Of 45 strains of Streptococcus hæmolyticus from bovine sources, including 26 strains isolated from milk and the udder of cows, and 19 from cream cheese, 40 reached a final hydrogen ion concentration of pH 4.3 to 4.5. Of the remaining 5 which reached a pH of 5.0 to 5.2, two were of known human type and three of uncertain diagnosis. 4. A rapid and practical application of this method is proposed as a presumptive test in the differentiation of human and bovine types of Streptococcus hæmolyticus.     

心衰,何病因?肺栓,是否溶?阿斯,谁之过?

正[病例简介]男,17岁。因胸闷1月余,加重伴发热、咯血2周。明显喘憋、下肢水肿5d入院。患者1月余前无明显诱因出现轻度胸闷、气短,登楼时明显,无其他伴随症状。2周前洗冷水澡后出现发热,体温最高达38.5℃,伴咽痛、咳嗽、咯痰,偶有痰中带血,在当地县医院摄X线胸片示:两肺纹理增多,心影增大,肺淤血?心脏超声示:全心增大,左室舒张功能受损,二尖瓣、三尖瓣、肺动脉瓣反流。心电图示:窦性心动过速,V_(1-3),导联r波纤细且上升不良。     

THE ACUTE EFFECTS OF VARIOUS TYPES OF STRETCHING STATIC,DYNAMIC, BALLISTIC,AND NO STRETCH OF THE ILIOPSOAS ON 40‐YARD SPRINT TIMES IN RECREATIONAL RUNNERS

Background and Purpose:

The potential adverse effects of static stretching on athletic performance are well documented, but still appears to be controversial, especially as they relates to sprinting. The prevalence of this practice is demonstrated by the number of competitive and recreational athletes who regularly engage in stretching immediately prior to sprinting with the mindset of optimizing their performance. The purpose of this study was to examine the effects of acute static, dynamic, and ballistic stretching, and no stretching of the iliopsoas muscle on 40‐yard sprint times in 18‐37 year‐old non‐competitive, recreational runners.

Methods:

Twenty‐five healthy recreational runners (16 male and 9 female) between the ages of 24 and 35 (Mean = 26.76 yrs., SD = 2.42 yrs.) completed this study. A repeated measures design was used, which consisted of running a 40‐yard sprint trial immediately following each of 4 different stretching conditions aimed at the iliopsoas muscle and lasting 1 minute each. The 4 conditions were completed in a randomized order within a 2‐week time period, allowing 48‐72 hours between each condition. Prior to each 40‐yard sprint trial, a 5‐minute walking warm‐up was performed at 3.5 mph on a treadmill. The subject then ran a baseline 40‐yard sprint. After a 10‐minute self‐paced walk, each subject performed one of the 4 stretching conditions (ballistic, dynamic, static, and no stretch) and then immediately ran a timed 40‐yard sprint.

Results:

There was a significant interaction between stretching conditions and their effects on sprint times, F(3,72) = 9.422, p<.0005. To break down this interaction, simple main effects were performed with 2 repeated measures ANOVAs and 4 paired t‐tests using a Bonferroni corrected alpha (α = .0083). There were no significant differences between the 4 pre‐condition times, p = 0.103 (Greenhouse‐Geisser) or the post‐condition times, p = 0.029. In the no stretch condition, subjects improved significantly from pre‐ to post‐ sprint times (p<0.0005). There were no statistically significant differences in pre‐ and post‐stretch condition sprint times among the static (p = 0.804), ballistic (p = 0.217), and dynamic (p = 0.022) stretching conditions.

Conclusions:

Sprint performance may show greatest improvement without stretching and through the use of a walking generalized warmup on a treadmill. These findings have clinically meaningful implications for runners who include iliopsoas muscle stretching as a component of the warm‐up.

Level of Evidence:

Level 2     

BACTERIAL VARIATION IN CULTURES OF FRIEDL?NDER'S BACILLUS

1. Under proper conditions mass R cultures of Friedländer''s bacillus may give rise to a number of variants which are dissimilar in colony appearance and morphology. Three such forms have been described. In two varieties, differences have been observed not only in colony formation and morphology, but also in cultural and antigenic characters. 2. None of the methods employed were adequate to cause reversion of any of the R variants to the S type. Growth of the R2 variant in its own antiserum, however, induced a change to the R1 form. 3. R forms of Friedländer''s bacillus may be derived from S strains by aging or by growth in anti-S serum of the homologous type. 4. R strains may be isolated in culture directly from infection. In the cases where R forms were found, S cells were also present, and the pathological condition was of a chronic nature.     

A COMPARATIVE STUDY OF EXPERIMENTAL PROPHYLACTIC INOCULATION AGAINST LEPTOSPIRA ICTEROH?MORRHAGI?

Guinea pigs were inoculated with suspensions of Leptospira icterohæmorrhagiæ obtained from pure cultures of several different strains, in order to determine whether or not an active immunity against a subsequent infection with virulent organisms would develop in the vaccinated animals. The experiments were so arranged as to make possible a determination of the existence of immunity against homologous strains as well as against the strains not employed as vaccine, and a brief quantitive estimation of the degree and duration of the immunity in relation to the quantities of the vaccines inoculated. Following the general rule of prophylactic inoculations with various pathogenic organisms, the inoculations were repeated subcutaneously on three consecutive occasions at intervals of 5 days. With respect to the amounts of vaccine, the experiments were divided into three groups for each vaccine, one group receiving three doses of 0.5 cc., the second three of 0.05 cc., and the third three of 0.005 cc. Four different strains were employed as vaccines, American Strain 1, American Strain 2, and one each of the Japanese and the European strains. The determination of the development, degree, and duration of the immunity was made by inoculating intraperitoneally several minimum lethal doses of each of the five following strains: American Strains 1, 2, and 3, the Japanese, and the European strains. The virulence of the different strains varied considerably, the strongest being the Japanese strain, which killed the guinea pig in a dose of 0.00001 cc., and the weakest American Strain 3, the minimum lethal dose of which was as large as 0.01 cc. The vaccinated guinea pigs were tested for immunity at the end of 2, 4, and 8 weeks after the last inoculation. The results obtained show that three successive inoculations of 0.5 cc. of the emulsions of killed cultures of Leptospira icterohæmorrhagiæ into guinea pigs rendered them completely resistant to a subsequent infection with the virulent cultures of both homologous and heterologous strains. With 0.05 cc. the protection was not so general, the animals succumbing to an experimental infection with some heterologous strains while resisting the homologous and other heterologous strains. The animals which were vaccinated with 0.005 cc. survived the infection experiments with the homologous strains in the case of American Strain 1 and the Japanese strain, but they were not protected against any other strains. The vaccines of other strains were unable to immunize the guinea pigs so highly even against their homologous strains, when the amount of each inoculation was only 0.005 cc., but 0.05 cc. conferred complete protection against the same strains. It may be concluded, therefore, that when a sufficient quantity of killed cultures of Leptospira icterohæmorrhagiæ is given, the guinea pigs will become immune to all strains of the same organism, but that smaller quantities may protect them against homologous but not against heterologous strains. A close analysis reveals the existence of group or type affinities among different strains which can be brought '' out by immunizing the animals with smaller quantities of killed cultures. In the present series of experiments American Strains 1 and 3 form one group, American Strain 2 and the European strain another, and the Japanese strain a third, which is also closely allied to the first group. In order to insure universal immunity it is wise to employ as many group or type cultures as possible in the preparation of vaccines, a polyvalent vaccine being recommended. It is not improbable that the strain recently encountered in Lorient, France, is an unusually deviated type of Leptospira icterohæmorrhagiæ, and that if successfully cultivated and used as vaccine in sufficient amount it might protect the animals against other strains of the same organism. The active immunity induced in the vaccinated guinea pigs was found to persist for at least 8 weeks after the last inoculation. It will no doubt last for a much longer period.     

THE BEHAVIOR OF BACILLUS LEPR? IN COLD-BLOODED ANIMALS

Before proceeding to a discussion of the experiments upon cold-blooded animals, it is necessary to review briefly some of the work recently done with the bacillus of leprosy. The appearance of the bacillus in man and its behavior under artificial cultivation, and in the tissues of lower animals, should be considered in order that comparisons may be drawn. In their studies with the organism under cultivation, Duval and Gurd pointed out that the long, slender, and beaded appearance of the leprosy bacillus described by Hansen, in 1872, is lost when removed for several generations from the parent stem, and under artificial cultivation the organism becomes unbeaded, short, and coccoid. Duval also noted that these changes in morphology were always followed by rapid multiplication of the organism. Duval argues, a priori, that the bacillus is not in a favorable environment in the human tissues. If these deductions are correct, the morphology of the leprosy bacillus should vary according to the resistance offered by the tissues of different animals. The resistance of the human host to the leprosy bacillus becomes more evident in the light of the clinical aspect of the disease. The long period of incubation, the duration of the disease, and the disappearance of the bacilli preceding the healing of the infected foci show that the resistance offered to the bacillus by the human tissues is not to be overestimated. This opinion is confirmed when the behavior of the leprosy bacillus under cultivation and in the tissues of various mammals is compared. When cats, rabbits, bats, guinea pigs, and rats are inoculated either below the skin or into the peritoneal cavity with large quantities of Bacillus lepræ, a slight local reaction follows within twenty-four to forty-eight hours, but no definite lesions are produced and the bacilli soon disappear. The resistance of some animals to Bacillus lepræ is well illustrated by two cats which were inoculated subcutaneously and intraperitoneally with a heavy suspension of Bacillus lepræ. These animals were killed and examined three days later, but the bacilli were not demonstrable from the regions about the sites of inoculation. Pigeons are likewise refractory. It is impossible to cause a local reaction in these birds, and the injected bacilli disappear rapidly. Hence, probably no multiplication takes place in them. Goats, young pigs, and white and dancing mice are in a degree susceptible to injections, and though undoubted lesions are produced, and multiplication of the bacilli occurs, the lesions and bacilli disappear after a limited time. Acid-fast bacilli which are recovered from the lesions are long, slim, and beaded, though the organisms used in the inoculations were short, unbeaded, and coccoid. Monkeys inoculated with cultures of the short unbeaded forms react promptly. The lesions resulting, though confined in most instances to the site of inoculation, occasionally appear at distant points. The number of bacilli present in the nodules and their arrangement within typical lepra cells show that multiplication has taken place. The organism has, however, changed from the short coccoid form to the long, slender, beaded form. Though the lesions induced and the bacilli present are in every way similar to those found in man, their tendency to disappear gradually after a quiescent stage clearly denotes that the tissues of the monkey, although less refractory than the tissues of the animals previously mentioned, still offer resistance to invasion. While mammals react but poorly to inoculations of the leprosy bacillus, this reaction manifests itself in various ways in different species. For example, while multiplication of the organism with the production of lesions occurs in some species, in others that are more refractory, the injected bacilli assume the involuted or beaded forms and do not multiply or produce lesions; in others, still more resistant to the action of the leprosy bacillus, the organisms quickly undergo granular metamorphosis and disappear. Furthermore, in some species the lesions are, in most instances, limited to the site of inoculation, and though presenting all the characteristics of the lesion in man, the nodules and the bacilli disappear after a variable time. This behavior of the leprosy bacillus can be accounted for only by the degree of resistance offered by the tissues of the individual host. Since the morphology of the organism invariably changes from the short coccoid to the large beaded form when placed in insusceptible animals, and conversely, from the long beaded forms to the short coccoid forms when placed in susceptible animals, the deduction can be drawn that the organism varies in morphology and rapidity of growth according to the susceptibility of the host. Examples of similar behavior of Bacillus lepræ in the human subject are known to all investigators of leprosy. Ulcers and nodular areas often heal, and the bacilli disappear with little or no treatment. It is true that while older lesions are healing, new ones are constantly appearing, yet the duration of the disease and its undoubted tendency towards healing shows that conditions in the human subject are variable, and suggests that the organism has its natural habitat in some other host. The experiments presented here serve to show that the bacillus of leprosy meets but little or no resistance in the tissues of cold-blooded animals, multiplies in their tissues, and may be harbored by them without apparent discomfort or external evidence of the disease. That no appreciable resistance is offered to the multiplication of the leprosy bacillus by many species of cold-blooded animals is shown by the fact that aside from the trauma produced by the inoculation and the slight initial reaction of the tissues, the organism continues to grow profusely, and to invade the tissues without further reaction. Quite the opposite condition occurs in mammals: in some of these the leprosy bacillus degenerates into a granular mass shortly after inoculation; in others that are less refractory, typical lesions appear, but they seldom extend from the point of inoculation; and while the bacilli multiply slowly, they do not infiltrate the tissues, but disappear after a short time, the lesions healing. That multiplication of Bacillus lepræ occurs in the tissues of cold-blooded animals is shown by the fact that while animals examined a few days after inoculation show but a few scattered organisms, those killed at longer intervals show a proportional increase in the number of bacilli. Furthermore, the few bacilli found at the early-period are extracellular and scattered, while after longer periods they tend to be massed and enclosed in large lepra cells. The supposition that these lepra cells are phagocytes has naturally arisen. Duval holds that they are not phagocytes in the true sense of the term, that the bacilli penetrate the cells rather than that the cells engulf them, after which, finding conditions for growth favorable, they multiply without causing serious injury to the cell. The size of the cell depends upon the size of the colony within. The experimental work bears out this view since the decrease in number of the organisms observed in animals killed shortly after inoculation depends not upon phagocytic action nor upon cells which appear later when active lesions are established. In early lesions, the lepra cells are smaller, barely measuring twenty to thirty microns in diameter, and contain but few bacilli; whereas in older ones, they attain a diameter of 100 microns or even more, and contain enormous numbers of bacilli. Were this increase in size due to phagocytic action, some cells would be found in which the limit of their capacity had been reached; and they would either contain a mass of dead and disintegrated bacteria or would themselves show evidence of disintegration. On the contrary, the bacilli, though they occupy most of the cell, show no signs of disintegration, and the nucleus and the cytoplasm of the cell retain normal staining properties. That the invasion and multiplication of the bacilli cause an irritation is evident by the amitotic divisions of the nucleus which occur in the larger cells. The absence of external evidence of invasion by Bacillus lepræ in cold-blooded animals, and the apparent lack of discomfort caused by the presence of the organism within their tissues, are points which should be remembered in considering the sources from which leprosy may be transmitted. In not a single instance in the numerous experiments presented here would it have been possible, from any external sign, to suspect that the animals were harboring multitudes of leprosy bacilli. While the evidence in support of the opinion that leprosy may be transmitted from man to man appears sufficiently strong to warrant this belief, the number of cases in which infection can be actually traced to this source is small. Since leprosy is known to be prevalent where fish and sea-food are plentiful, and since the experiments here recorded prove that fish can be infected by being fed cultures of Bacillus lepræ, or nodules from human lepers, or bits of fish previously infected with the leprosy organism, account should be taken of the possibility that leprosy, in certain localities, may arise from this source of infection. The question as to how and from what source leprosy bacilli enter the human body may be still regarded as an open one. Isolated examples of direct infection of healthy human beings from lepers have been reported by Arning and Nonne, by Manson, and others. The notion that the agency of infection is already infected human beings, that is lepers, is at the foundation of the modern practice of the isolation and segregation of lepers, which would seem to have brought about a definite decrease in the prevalence of the disease. It is an acknowledged fact, however, that the lepers confined in institutions practically never cause infection of nurses, etc. Some other factor than the human agency may therefore be considered as affecting this issue. It is well known that Jonathan Hutchinson has brought forward the idea that fish are the source of the infection, basing the view on the high prevalence of the disease along the coast countries of Norway and Sweden, and in the Pacific Islands, and in the countries bordering the Mediterranean and Black Seas, in all of which fish furnish the chief food material. No convincing proof was ever adduced in support of this contention. But now that it has been shown that the leprosy bacillus survives and multiplies in cold-blooded animals, at least at room temperature in a warm climate, and since methods have been devised for cultivating and identifying the leprosy bacillus, the question has been opened up to accurate investigation. Duval has shown that the leprosy bacillus in cultures grows better at room temperature than at 37° C., so that growth in cold-blooded animals kept at room temperature is perhaps in some way connected with this phenomenon. What must now be ascertained, in order to test the Hutchinsonian theory more accurately is whether such growth takes place at a temperature corresponding with the average mean temperature of such a body of water as the North Sea and that of the fiords of Norway. Since cold-blooded animals possess the same temperature as their surroundings, they would be suitable media for the cultivation of leprosy bacilli at those temperatures. For the waters of the Mediterranean Sea and the tropical Pacific Ocean, this consideration would count less. But the theory will stand or fall according as it can account for the whole, and not only for a part, of the phenomena to be explained. As the length and shape of the bacilli and the number of chromatin masses are constant for a given species of cold- or warm-blooded animals, which features are governed by the resistance of the individual species, the following conclusions seem justified: that the morphology and rapid multiplication of the leprosy bacillus in cultures and in some species of cold-blooded animals indicate that Bacillus lepræ under natural conditions is short, coccoid, and un-beaded, and that the long, slender, beaded variety which occurs in the mammalian species is atypical and the product of an unfavorable environment.     

THE R?LE OF THE RETICULO-ENDOTHELIAL SYSTEM IN IMMUNITY : I. THE R?LE OF THE RETICULO-ENDOTHELIAL SYSTEM IN THE PRODUCTION OF DIPHTHERIA ANTITOXIN.

1. Following massive doses of India ink injected intravenously into guinea pigs before a subcutaneous injection of diphtheria toxin-antitoxin mixture, no antitoxin was found in the blood serum for 3 weeks, as indicated by intracutaneous tests, whereas an appreciable amount could be detected in non-blocked, immunized control animals. 2. During the 4th week following immunization, the titer of the serum of blocked animals equaled that of non-blocked controls within the limits of the intracutaneous test dose. 3. The smaller doses of India ink used in these experiments, given before immunization, had no stimulating effect on the production of diphtheria antitoxin but, on the contrary, also inhibited the appearance of this antibody, although to a less extent.     

THE PROPHYLAXIS OF WEIL'S DISEASE (SPIROCH?TOSIS ICTEROH?MORRHAGICA)

We have already described briefly the portals of entry and of excretion of the pathogenic spirochetes. We may mention here that we have twice prevented epidemics by disinfection of the ground and the removal of the inundated water in certain places in coal mines. In one mine 19 out of 50 workmen, and in another 9 out of 30 workmen came down with Weil''s disease in about 2 weeks. We have already pointed out that the period during which the pathogenic spirochetes are excreted in the urine continues, as a rule, for 40 days, and that we must, therefore, apply disinfection for at least 40 days after the first appearance of the disease. Lately we have found that in 21 cases out of 24 the spirochetes were excreted in the urine for 40 days, in one case until the 42nd day, in one case until the 45th day, and in still another case until the 63rd day. Another important fact concerning the prophylaxis which has been brought out is that both house and ditch rats (brown) carry virulent Spirochæta icterohamorrhagæ, the causal spirochete of Weil''s disease, in their kidneys. Miyajima has reported that field rats have the pathogenic organisms in their kidneys; he will report these findings in detail later. The spirochetes which he described are less virulent than ours. On his advice we have carefully examined house and ditch rats in the city and rats in the coal mines of Kyushu, where Weil''s disease prevails, and found that 39.5 per cent carried highly virulent pathogenic spirochetes in their kidneys, thus confirming Miyajima''s experiments. The kidneys were examined microscopically under the dark-field microscope, and in the cases in which we did not find the pathogenic spirochete, we made inoculations into guinea pigs. Thus we found Spirochæta icterohæmorrhagiæ microscopically in the kidneys or in the urine in 32.4 per cent, and by means of inoculation in 7 per cent, making a total of 39.5 per cent carrying the pathogenic organisms, out of a total number of 86 rats examined. In some instances, rats were made to bite guinea pigs and in two instances caused Weil''s disease. Among fifty-five patients in our clinic, twelve were cooks; and in Europe many cases arise among butchers—indicating the relation of the disease to rats. Moreover, during the present year we observed two patients who acquired Weil''s disease, one in 1 week, the other 8 to 9 days after they had been bitten by rats. These facts point to a relation between Weil''s disease and rats. The infection is transmitted probably from rats to man by means of the urine of the rats, directly or indirectly. On the injection of 0.1 gm. of rat urine which contains Spirochæta icterohæmorrhagiæ into the peritoneal cavity of guinea pigs, the infection arises, while the injection of the liver or the blood of the rats into guinea pigs does not produce the typical disease. The finding that the kidneys of rats contain the pathogenic organisms of the disease is important from the point of view of prophylaxis. The large number of rats in the trenches of the European battle-fields suggests the possibility that many cases of Weil''s disease may arise. We shall report on this point in more detail later.     

COMPARISON OF TRUNK AND LOWER EXTREMITY MUSCLE ACTIVITY AMONG FOUR STATIONARY EQUIPMENT DEVICES: UPRIGHT BIKE,RECUMBENT BIKE,TREADMILL, AND ELLIPTIGO?

Background

Stationary equipment devices are often used to improve fitness. The ElliptiGO® was recently developed that blends the elements of an elliptical trainer and bicycle, allowing reciprocal lower limb pedaling in an upright position. However, it is unknown whether the muscle activity used for the ElliptiGO® is similar to walking or cycling. To date, there is no information comparing muscle activity for exercise on the treadmill, stationary upright and recumbent bikes, and the ElliptiGO®.

Purpose/Hypothesis

The purpose of this study was to assess trunk and lower extremity muscle activity among treadmill walking, cycling (recumbent and upright) and the ElliptiGO® cycling. It was hypothesized that the ElliptiGO® and treadmill would elicit similar electromyographic muscle activity responses compared to the stationary bike and recumbent bike during an exercise session.

Study Design

Cohort, repeated measures

Methods

Twelve recreationally active volunteers participated in the study and were assigned a random order of exercise for each of the four devices (ElliptiGO®, stationary upright cycle ergometer, recumbent ergometer, and a treadmill). Two-dimensional video was used to monitor the start and stop of exercise and surface electromyography (SEMG) were used to assess muscle activity during two minutes of cycling or treadmill walking at 40-50% heart rate reserve (HRR). Eight muscles on the dominant limb were used for analysis: gluteus maximus (Gmax), gluteus medius (Gmed), biceps femoris (BF), lateral head of the gastrocnemius (LG), tibialis anterior (TA), rectus femoris (RF). Two trunk muscles were assessed on the same side; lumbar erector spinae at L3-4 level (LES) and rectus abdominus (RA). Maximal voluntary isometric contractions (MVIC) were determined for each muscle and SEMG data were expressed as %MVIC in order to normalize outputs.

Results

The %MVIC for RF during ElliptiGO® cycling was higher than recumbent cycling. The LG muscle activity was highest during upright cycling. The TA was higher during walking compared to recumbent cycling and ElliptiGO® cycling. No differences were found among the the LES and remaining lower limb musculature across devices.

Conclusion

ElliptiGO® cycling was found to elicit sufficient muscle activity to provide a strengthening stimulus for the RF muscle. The LES, RA, Gmax, Gmed, and BF activity were similar across all devices and ranged from low to moderate strength levels of muscle activation. The information gained from this study may assist clinicians in developing low to moderate strengthening exercise protocols when using these four devices.

Level of evidence

3