A CONTRIBUTION TO THE EPIDEMIOLOGY OF LOBAR PNEUMONIA

1. Pneumococci of Type I and Type II are responsible for the majority of the cases of lobar pneumonia. 2. Among the pneumococci found in the mouths of healthy individuals, Type IV predominates, Type III is fairly frequent, and atypical organisms of Type II are occasionally encountered. Organisms of these types give rise to a minority of cases of lobar pneumonia. 3. Healthy persons intimately associated with cases of lobar pneumonia may harbor in their mouth secretions the highly parasitic pneumococci of Types I and II. 4. Occasionally a carrier of Type I or Type II pneumococcus is encountered in whom it is impossible to trace any contact with an infected patient. 5. Convalescents from lobar pneumonia may carry for a considerable period of time the type of pneumococcus with which they were infected.     

FURTHER STUDIES ON THE EPIDEMIOLOGY OF LOBAR PNEUMONIA

1. Pneumococci of Type I and Type II are responsible for the majority of the cases of lobar pneumonia. 2. Among the pneumococci found in the mouths of healthy individuals Type IV predominates, Type III is frequent, and atypical organisms of Type II are occasionally found. 3. Healthy persons intimately associated with cases of lobar pneumonia may harbor in their mouth secretions the highly parasitic pneumococcus of Types I and II. 4. Occasionally a carrier of Type I or Type II pneumococcus is encountered in whom it is impossible to trace any contact with an infected patient. 5. From the dust of homes where cases of pneumonia due to Types I and II have occurred, pneumococci of the same type may be recovered.     

THE OCCURRENCE OF CARRIERS OF DISEASE-PRODUCING TYPES OF PNEUMOCOCCUS

Lobar pneumonia in 75 per cent of instances is due to specific types of pneumococci possessed of a high degree of pathogenicity. Although pneumococci occur in the mouths of 60 per cent of normal individuals, such organisms are readily distinguishable from the highly parasitic types of pneumococcus responsible for the severe forms of lobar pneumonia, a convincing proof that infection in this disease is, in the majority of instances, not autogenic in nature, but is derived from some extraneous source. In a high percentage of instances healthy persons intimately associated with cases of lobar pneumonia harbor the disease-producing types of pneumococcus. In every such instance the pneumococcus isolated has corresponded in type with that of the infected individual. Convalescents from pneumonia carry for a considerable length of time the type of pneumococcus with which they have been infected. The existence of the carrier state among healthy persons and among those recently recovered from pneumonia establishes a basis for understanding the mechanism by means of which lobar pneumonia spreads and maintains its high incidence from year to year.     

A FURTHER STUDY ON THE BIOLOGIC CLASSIFICATION OF PNEUMOCOCCI

1. At least three subgroups of Pneumococcus Type II may be recognized by specific immune reactions. They have been called Subgroups II A, II B, and II X. 2. That the organisms of these three subgroups are biologically related to Pneumococcus Type II is shown by the following facts: (a) Agglutination with Antipneumococcus Serum II. (b) Protection with Antipneumococcus Serum II, except Subgroup II X. (c) Absorption of Antipneumococcus Serum II with typical Type II pneumococcus removes the antibodies for all subgroups, (d) Absorption of Antipneumococcus Serum II with a member of Subgroups II A or II B removes only the antibodies for the homologous subgroup. Absorption of Antipneumococcus Serum II with any given member of Subgroup II X removes the antibodies for that particular strain only. 3. That the three subgroups, although biologically related to Pneumococcus Type II, possess, nevertheless, specific differential characterswhich separate them one from another, is evidenced by thefollowing facts: (a) The organisms of any subgroup are not agglutinated bythe antisera of the other two subgroups. (b) They are not protected against by the sera of the other subgroups. (c) They do not absorb from Antipneumococcus Serum II the specific immune bodies of the other subgroups. 4. Subgroups II A and II B are characterized by immunity reactions identical within the respective group. 5. Subgroup II X consists of heterogeneous strains which do not cross in their immunity reaction with each other or with Subgroups II A or II B.     

THE OXYGEN OF THE ARTERIAL AND VENOUS BLOOD IN PNEUMONIA AND ITS RELATION TO CYANOSIS

1. A simple method for arterial puncture is given which does no permanent injury to the artery. Arterial and venous punctures have been done on 33 cases of pneumonia and five normal subjects, and the blood thus obtained has been studied with reference to the oxygen capacity and arterial and venous unsaturation. 2. In five normal subjects the mean arterial unsaturation was 5 per cent of the total oxygen capacity; the mean venous unsaturation was 26.8 per cent. 3. In the pneumonia cases the arterial oxygen unsaturation varied over a wide range. The arterial unsaturation varied from 0.0 to 68.2 per cent, the venous from 14.4 to 85.5 per cent. In the fatal cases as opposed to the non-fatal cases of pneumonia, the mean arterial oxygen unsaturation was 32 per cent as against 13.9 per cent. As a rule, an arterial unsaturation of over 20 per cent was associated with a fatal outcome. Similarly, the mean venous oxygen unsaturation was 57 per cent in the fatal cases and 36.3 per cent in the non-fatal cases. 4. In five cases in which no cyanosis was observed at any time the mean arterial oxygen unsaturation was 5.4 per cent, the mean venous oxygen unsaturation 31.5 per cent. In cases which showed cyanosis of varying degree during the course of the illness, the mean arterial unsaturation was 24.7 per cent, and the mean venous unsaturation 44.5 per cent. Cases without cyanosis have an arterial unsaturation close to the normal. 5. There is a definite relation between the degree of cyanosis and the per cent of arterial unsaturation. With increasing cyanosis the arterial unsaturation becomes greater. The venous unsaturation varies similarly. 6. In individual cases with marked cyanosis associated with high arterial unsaturation, the clinical improvement of the patient and the diminution of the cyanosis are accompanied by a similar diminution in the arterial and venous unsaturation. Conversely, an increase of cyanosis is accompanied by an increase in arterial unsaturation. It is evident that the cyanosis of pneumonia patients is due to the incomplete saturation of venous blood with oxygen in the lungs, and that the various shades of blue observed in the distal parts are caused by an admixture of reduced hemoglobin and oxyhemoglobin in the superficial capillaries. 7. No unusually low total oxygen capacities were observed, even in fatal cases with intense cyanosis. On the contrary, in these cases the total oxygen capacity was unusually high, pointing toward a concentration of the blood. Again in only one case was there any marked fall in the oxygen capacity during the illness. Therefore, methemoglobin formation, in these cases, can hardly have occurred to such an extent as to be an important factor in the production of cyanosis. Of the 33 cases studied, however, only seven were lobar pneumonia, the rest being of types ordinarily unusual, which have accompanied the recent influenza epidemic; and of the seven, not all were in all respects typically lobar. The possibility still remains, therefore, that in typical lobar pneumonia caused by the pneumococcus methemoglobin may play a part in the cyanosis. 8. The oxygen consumption, i.e. difference between arterial and venous contents, was within normal limits, indicating that the cardiac output was not diminished in the cases (chiefly post influenza) of pneumonia studied.     

THE OCCURRENCE AND VIRULENCE OF PNEUMOCOCCI IN THE CIRCULATING BLOOD DURING LOBAR PNEUMONIA AND THE SUSCEPTIBILITY OF PNEUMOCOCCUS STRAINS TO UNIVALENT ANTIPNEUMOCOCCUS SERUM

Studies of the bacteriology of the blood were made in thirty-seven cases of lobar pneumonia. The pneumococcus was isolated from the blood in approximately 50 per cent. of the cases studied. The course of infection in individuals with pneumococcus in the blood was more severe than in those in which no organism could be cultivated from the blood. 77 per cent. of the patients with positive blood cultures died, and 79 per cent. of patients with negative blood cultures recovered. In fatal instances of pneumonia, where the pneumococcus was found in the blood, the number of organisms per cubic centimeter of blood was very high in the last stage of the disease. In individuals dying of pneumonia without blood infection, the disease was characterized by a rapid spread of the local process in the lungs. It is not unlikely that the symptoms of collapse, developing on the fifth or sixth day of lobar pneumonia, are often the expression of serious invasion of the blood by the pneumococcus. In other instances, they mark an extension of the local process in the lungs. Strains of pneumococcus isolated from the blood of patients with lobar pneumonia were usually of high animal virulence. In a few instances where the organism isolated from the blood was of low virulence for animals, the patients recovered. The protective power of a univalent antipneumococcus serum was tested against nineteen strains of typical pneumococcus and against four strains of closely allied organisms. The serum manifested some degree of protection against twelve out of nineteen strains of typical pneumococci. No protection was observed against the atypical organisms. In eight instances the degree of protection obtained was high, in three low, and in one there occurred only a prolongation of the period of life of the inoculated animal.     

Use of pooled sodium acetate acetic acid formalin-preserved fecal specimens for the detection of intestinal parasites

This study aimed at comparing detection of intestinal parasites from single unpreserved stool sample vs. sodium acetate acetic acid formalin (SAF)-preserved pooled samples, and stained with chlorazol black dye in routine practice. Unpreserved samples were collected from 120 patients and represented as Group I. Other three SAF-preserved samples were collected from the same patients over a 6-day period and represented as Groups IIa, IIb, and IIc. The latter groups were equally subdivided into two subgroups. The first subgroup of each of the three samples was examined individually, whereas the second subgroup of each were pooled and examined as a single specimen. All groups were examined by the routine diagnostic techniques; however, in group II when the diagnosis was uncertain, the chlorazol black dye staining procedure was carried out. Results demonstrated that out of 74 patients who continued the study, 12 cases (16%) were positive in group I, compared with 29 (39%) in the subgroups examined individually, and 27 (36%) in the pooled subgroups. Therefore, pooling of preserved fecal samples is an efficient and economical procedure for the detection of parasites. Furthermore, the chlorazol black dye was simple and effective in detecting the nuclear details of different parasites.     

THE SPECIFIC POLYSACCHARIDE CONTENT OF PNEUMONIC SPUTA

1. The average specific polysaccharide content of rusty or bloody sputa in Type III was 91 times greater than the average for Types I, II, VII, and VIII pneumonia. 2. Those Type III sputums which were classified as reticulated contained an average S concentration of 1,360 mg. per cent or 170 times more than the amount found in other types. 3. Those Type III sputa which were classified as non-reticulated contained an average S concentration of 45 mg. per cent or 5.5 times more than the amount found in other types. 4. The amount of specific polysaccharide in the sputa of patients with Type III pneumonia furnishes an index to the severity of the disease and an aid in prognosis.     

Risk Factors of Adverse Presentation as the First Arrhythmia in Wolff‐Parkinson‐White Syndrome

Background: The aim of the study was the evaluation of the predictors of adverse presentation as first arrhythmia in Wolff‐Parkinson‐White syndrome; they usually affect young patients with septal or multiple accessory pathways (AP). Methods: Our population comprised 645 patients with a preexcitation syndrome. Among them, adverse presentation (sudden death, hemodynamically not tolerated atrial fibrillation [AF]) occurred in 60 (9%) (group I). Their clinical and electrophysiological features were compared to group II patients, which consisted of 75 patients with syncope (IIa), 287 with reentrant tachycardia (RT) (IIb), 211 asymptomatic patients (IIc), and 12 with well‐tolerated AF. Results: Sixteen group I patients had triggering factors. Group I patients were older (40 ± 18.5) than group II (34 ± 16) (P = 0.02). Male gender was as frequent in both groups (63%, 59%). Free wall left AP was more frequent in group I (65%) than in group II (37%) (P < 0.001), septal AP less frequent (27% vs 47%) (P = 0.004), multiple APs exceptional. RT was more frequent in group I (57%) than in group IIc (12%) (P < 0.001), less frequent than in group IIb (90.5%) (P < 0.001). AF was more frequent in group I (85%) than in group IIc (22%), or IIb (19%) (P < 0.001). Maximal rate through AP was higher in group I than in group II (P < 0.001). Conclusions: Adverse presentation in WPW may affect patients older than 35 years of both sexes, with a single free wall lateral AP. All could have been identified by an electrophysiological study. (PACE 2010; 33:1074–1081)     

VARIETIES OF PNEUMOCOCCUS AND THEIR RELATION TO LOBAR PNEUMONIA

A study of pneumococci isolated from individuals suffering from lobar pneumonia has shown that the majority of these organisms fall into definite biological groups. These groups have been arbitrarily numbered from I to IV. The first three groups consist of organisms which within the group are closely related to each other by certain immunological reactions; i. e., protection and agglutination. Extensive study has failed to reveal crossing in either of these reactions between members of separate groups. The fourth group is formed of a series of independent varieties which cannot be definitely related to one another by the immune reactions employed. Up to the present time we have observed no tendency of these organisms to lose their specific characters, nor have we observed a change of one type into another. These groups vary in their pathogenicity for human beings, and in the order of their virulence are as follows: group III, group II, group I, group IV. The degree of protective power developed in the sera of animals immunized against members of the different groups varies inversely with the virulence and with the amount of capsular development. This, however, applies only to tests of passive immunity. The highly virulent groups give as good active immunity as those of lower virulence, if not better. In view of these constant differential characters of the pneumococcus, it was deemed advisable to study the pneumococci occurring in normal sputum. It has been commonly assumed that infection in pneumonia is autogenic, and occurs from the invasion of the lungs by a pneumococcus habitually carried in the mouth. If this is so, we should find the same types in the normal mouth as occur during the disease. Examination of a series of normal individuals showed this not to be the case. In no instance was an organism found which could be grouped with any of the fixed types of pneumococcus. All exhibited the same characters as those organisms obtained from lobar pneumonia which belong to group IV. Inasmuch as organisms belonging to this group are of low virulence, and are responsible in our experience for only 20 per cent. of the cases of pneumonia, it is at once manifest that the majority and more virulent cases of pneumonia are due to organisms which are not found in normal mouths. To gain further evidence of this difference, a study has been made of convalescents from pneumonia who had been infected by typical organisms. During the period of recovery these typical organisms are supplanted by the type which occurs in normal mouths. The period of disappearance of the typical varieties has varied. The shortest time in which disappearance has occurred has been twelve days, and the longest period in which typical organisms have been carried has been ninety days. In the latter instance the patient was lost sight of, so that he may well have carried the virulent form for a longer period of time. In general, when typical organisms persist for a long time, there is delay in the healing of the lung lesion. If recovery is prompt, as a rule the virulent types disappear rapidly. We have said that the virulent types do not occur in normal mouths. There are exceptions to this observation. In a number of instances organisms belonging to the typical groups have been isolated from the mouth sputum of healthy individuals. So far this has occurred only in individuals intimately in contact with cases of lobar pneumonia. Wherever typical organisms have been obtained under such circumstances, the type has always corresponded to that with which the case of pneumonia was infected. Such individuals, therefore, become infected with virulent types of pneumococcus by contact, and may be regarded as healthy carriers of disease-producing types. This study makes it probable that the majority of cases of pneumonia are dependent upon either direct or indirect contact with a previous case. Mere infection of the mouth by virulent types is by no means sufficient to cause the disease. In order to invade the lungs, these virulent types must find the circumstances favorable, or a suitable condition must arise during the period when they are harbored in the mouth. Comparative study of certain strains of pneumococci received from South Africa suggests that new groups of parasitic organisms develop only during the period of high racial susceptibility. A like condition of affairs is brought about when a group of hitherto unexposed individuals is brought into contact with an infectious microörganism. The development of racial immunity soon limits the number of new types which may arise. The suggestion is made that strictly parasitic races of microorganisms are pure lines and have established themselves as parasites during a period of high racial susceptibility.     

CUTANEOUS REACTIONS IN PNEUMONIA. THE DEVELOPMENT OF ANTIBODIES FOLLOWING THE INTRADERMAL INJECTION OF TYPE-SPECIFIC POLYSACCHARIDE

The majority of patients convalescent from pneumonia due to Types I, II and III Pneumococcus develop at the time of recovery circulating antibodies for the homologous type of organisms. At the same time an immediate wheal and erythema reaction followed the intradermal injection of the homologous type-specific polysaccharide in 100 per cent of Type I patients, 58.8 per cent of Type II patients, and 44 per cent of Type III patients. In a group of 18 patients repeatedly tested with the type-specific polysaccharides, 10 developed in the second or third week of convalescence circulating antibodies for one or more heterologous types. In none of 21 control patients was this phenomenon observed. It is suggested that the development of circulating antibodies for heterologous types of Pneumococcus was associated with the previous intradermal injections of the type-specific polysaccharides.     

STUDIES ON MENINGOCOCCUS INFECTION : VII. THE STUDY OF AN ISOLATED EPIDEMIC

The investigation of this isolated epidemic of meningococcus meningitis at a C.C.C. camp gave an opportunity to examine the carrier state in contacts carrying what were presumably virulent epidemic strains of organisms. With the aid of Miller''s technique for the enhancement of the demonstrable virulence of meningococci for mice, it proved possible to test the virulence of the carrier strains from Camp Rusk. These results were consistent despite the interval of from 3 to 4 weeks which intervened between the isolation of the strains and the virulence titrations. Type I strains were found to have a high virulence, while the virulence of Type II strains was moderately high but definitely less than that of the Type I, and atypical strains and strains of N. catarrhalis isolated from carriers showed a very low virulence. The question of the precise nature of the carrier state was investigated. No evidence has been obtained yet as to the existence of a relationship between pharyngitis, coryza or upper respiratory disease and the presence and degree of the carrier state. This is unlike the situation with regard to pneumococcus carriers. On the other hand, it has proved possible to demonstrate reactions within the body to the meningococci in the nasopharynx, consisting of the formation of agglutinins and protective antibodies in the blood serum. 32.3 per cent of Type I and 60 per cent of Type II carrier sera showed moderate or good agglutinins for homologous organisms and 80 per cent of Type I and 40 per cent of Type II sera showed moderate or good protective antibodies against virulent homologous strains. No idea could be obtained as to the relationship of the presence or absence and the degree of serological reaction and the duration of the carrier state.     

Synthesis of cyanopyridine and pyrimidine analogues as new anti-inflammatory and antimicrobial agents

A new series of substituted benzylidene acetophenone (Ia-Ih), 2-amino-4, 6- substituted diphenylpyridine-3-carbonitrile (IIa-IIh) and 4, 6-substituted diphenylpyrimidin-2-amine (IIId-IIIg) were synthesized and evaluated for anti-inflammatory and antimicrobial activities. Four compounds (Ie, If, IIh and IIId) have shown good anti-inflammatory activity when compared to standard drug indomethacin. Two compound (Ie and IIh) displayed significant activity against gram -ve bacteria (E. Coli) and three compounds (IId, IIf and IIIh) displayed good activity against gram +ve bacteria (S. aureus) on comparison with the standard drug ofloxacin.     

STUDIES ON MENINGOCOCCUS INFECTION : X. A FURTHER NOTE ON THE PRESENCE OF MENINGOCOCCUS PRECIPITINOGENS IN THE CEREBROSPINAL FLUID

Precipitin tests have been carried out on spinal fluid from cases of meningococcal and other forms of meningitis, with monovalent anti-meningococcus horse serum of high titer. Using such a test it has been possible within 2 hours to diagnose and type cases of Type I and Type II meningococcal meningitis. In a certain number of cases fluids which were negative when first drawn became positive after standing for 1 or 2 days at 37°C. or room temperature. In 9.5 per cent of all Type I cases the fluids did not become positive. Fluids from cases due to atypical meningococci may react with the type serum of the group to which they belong (i.e., Types II* and VII, which belong to group II, with Type II serum) but do not in every case. Fluids from forms of meningitis other than meningococcal give no reaction. The use of concentrated sera is not advantageous at present, owing to the heterologous reactions which occur.     

Serum and lipoprotein apolipoprotein B levels in normal subjects and patients with hyperlipoproteinaemia.

Apolipoprotein B (apo B) levels were measured by radioimmunoassay in the serum and lipoproteins from normal subjects and patients with hyperlipoproteinaemia. The total serum apo B concentration in normal subjects was 0.91 +/- 0.16 g/l (mean +/- S.D.); in type IIa hyperlipoproteinaemia it was 2.24 +/- 0.61 g/l; in type IIb, 3.05 +/- 1.24 g/l; in type IV, 2.24 +/- 0.99 g/l; and in type V, 1.30 +/- 0.16 g/l. In normal subjects 5.6 +/- 2.1% (mean +/- S.D.) of total apo B was present in very low density lipoproteins (VLDL) and 93 +/- 9% in low density lipoproteins (LDL). Corresponding values for type IIa were 3.8 +/- 1.9% and 93 +/- 3%, for type IIb, 9.9 +/- 7.5% and 91 +/- 1%, for type IV, 16.9 +/- 9.5% and 81 +/- 9%, and for type V, 38.4 +/- 11.0% and 52 +/- 8%. The ratio of cholesterol to apo B in serum was decreased in types IIa, IIb and IV, and increased in type V whereas the ratio of triglyceride to apo B in serum was decreased in type IIa, normal in type IIb and increased in types IV and V. The ratio of cholesterol to apo B in VLDL was increased in types IIa, IIb and V, but normal in type IV, whereas in LDL, this ratio was normal in types IIa and V but reduced in types IIb and IV. The ratio of triglycerides to apo B in VLDL was normal in types IIa, IIb and IV but raised in type V. In LDL, this ratio was increased in types IIb and IV but normal in types IIa and V.     

Implications of decreased serum adiponectin for type IIb hyperlipidaemia and increased cholesterol levels of very-low-density lipoprotein in type II diabetic patients

The present study was performed to investigate the relevance of cholesterol levels of plasma lipoproteins [HDL (high-density lipoprotein), LDL (low-density lipoprotein), IDL (immediate-density lipoprotein), VLDL (very-LDL) and chylomicrons] determined by a novel HPLC method, with adiponectin, which is decreased in Type II diabetes and assumed to be involved in dysregulated metabolism and atherogenesis. Type II diabetic patients who were not treated with insulin, statins and fibrates were enrolled. Study subjects included Type II diabetic patients with normolipidaemia (DM-NL; n=15), type 4 hyperlipidaemia (DM-T4HL; n=13), Type IIa hyperlipidaemia (DM-T2aHL; n=15) and Type IIb hyperlipidaemia (DM-T2bHL; n=13). Fasting blood samples were collected. The serum adiponectin level was lower in DM-T2bHL than in any of the other groups. Cholesterol levels of each lipoprotein fraction, serum triacylglycerol (triglyceride), remnant-like particle-cholesterol, fasting plasma glucose, HbA1c (glycated haemoglobin), age, gender difference and BMI (body mass index) were incorporated into a stepwise regression analysis as independent variables. VLDL-cholesterol correlated inversely with adiponectin independently of age, BMI, gender difference and glycaemic control. Although the mechanisms remain to be explored, serum adiponectin was reduced particularly in Type II diabetics with type IIb hyperlipidaemia and correlated inversely with VLDL-cholesterol. Measuring VLDL-cholesterol may be helpful for understanding the pathological features of diabetic dyslipidaemia.     

Gastric adenoma with atypical appearance: findings on double-contrast barium study with histopathologic correlation

BACKGROUND: To describe the radiologic findings of nonpolypoid gastric adenomas and to correlate them with pathologic findings. METHODS: During a 9-year period, we reviewed 49 pure gastric adenomas in 43 patients with positive radiologic findings. Of these adenomas, seven with atypical polypoid appearance were retrospectively included in the study. We reviewed these findings with double-contrast barium study and correlated them with the pathologic findings. RESULTS: Of seven nonpolypoid adenomas, four were depressed and three were flat at pathologic examination. All were diagnosed as early gastric carcinoma (five as type IIc, one as type IIb, one as type IIa + IIc) in upper gastrointestinal series. Three were located in the gastric angle, two in the lower body, and two in the antrum. Size ranged from 10 mm to approximately 25 mm (mean = 15 mm). Six lesions had nodular surface and five had convergency of the mucosal folds. A shallow depressed area was seen in six lesions. CONCLUSIONS: A considerable proportion of gastric adenomas presents as a depressed or flat lesion on double-contrast barium study because of histologic characteristics of decreased subjacent mucosa. Because the nonpolypoid adenoma has a greater potentional for malignancy, more precaution is needed during the follow-up of this uncommon lesion.     

The metabolism of low density lipoprotein in endogenous hypertriglyceridaemia.

The metabolism of low density lipoprotein (LDL) was studied in eighteen hypertriglyceridaemic patients by injecting autologous radioiodinated LDL. Over 95% of the label was bound to the protein moiety of LDL and therefore the metabolic data reflect the fate and distribution of LDL apoprotein (apo B). The hypertriglyceridaemic subjects included ten with Type V, five with Type IV, two with Type III and one with Type IIb hyperlipoproteinaemia. For comparison identical studies were carried out in seven normal subjects and five patients with heterozygous familial hyperbetalipoproteinaemia (Type IIa). The groups differed considerably in mean LDL-cholesterol concentration. The patients with Type V lipoprotein pattern had significantly lower LDL-cholesterol concentration (mean 0.754 g/1) than the normal group (mean 1.237 g/1). Raised LDL-cholesterol levels were observed in all patients with heterozygous familial hyperbetalipoproteinaemia. The synthetic rate of LDL-apoprotein was found to be similar in all three groups (hypertriglyceridaemic, normal and hypercholesterolaemic). The highest synthetic rate was observed in the patient with Type IIb pattern. However, the fractional catabolic rate (FCR) of LDL-apoprotein differed significantly. The highest mean FCR was found in the Type V group (0.65 +/- 0.17 day-1) compared with 0.41 +/- 0.09 day-1 in the normal group and 0.185 +/- 0.05 day-1 in the Type IIa group. A strong inverse correlation was found between FCR and LDL apoprotein concentration in the whole series (r = -0.90, p less than 0.001) as well as within the Type V group (r = -0.87, p less than 0.01). These data indicate that the low plasma levels of LDL frequently observed in patients with very high plasma triglyceride levels are due to a high removal rate of LDL in these patients rather than to abnormal LDL synthesis.     

STUDIES ON CYANOSIS : I. PRIMARY CAUSES OF CYANOSIS.

1. Oleate hemoglobin agar is a good selective culture medium for Bacillus influenzæ. 2. Bacillus influenzæ has been cultivated from the mouth of 93 per cent of cases of influenza and bronchopneumonia. 3. Bacillus influenzæ was present at the time of this study in the mouths of 43 per cent of normal individuals. 4. The types of pneumococci found associated with the complicating bronchopneumonias of influenza are the types which are usually found in normal mouths.     

MR及动态增强对复发性鼻咽纤维血管瘤的诊断价值

目的评价复发性鼻咽纤维血管瘤的常规MR及动态增强表现,分析其累及的解剖结构,初步探讨复发原因。方法回顾性分析18例经手术病理证实的复发性鼻咽纤维血管瘤的MRI及动态增强表现。18例均行常规MRI平扫检查,15例同时行普通MR增强扫描,7例同时行MR动态增强扫描并后处理得到时间-信号强度变化(TIC)曲线。结果分期及部位:18例术前Ⅱb期4例,Ⅱc期9例,Ⅲa期4例,Ⅲb期1例,均累及翼腭窝和腭动脉供血区,13例累及颈内动脉分支供血区;复发后Ⅱa期5例,Ⅱb期4例,Ⅱc期9例,均累及翼腭窝。MR平扫示术前肿瘤横轴长度大于纵轴,形态不规则、边界模糊,T_1WI、T_2WI信号混杂;复发后瘤体形态较规整,呈圆形或卵圆形,边界清楚,信号混杂程度较术前轻。MR普通及动态增强示术前肿瘤明显欠均匀强化,复发后亦呈明显强化,但较术前均匀,7例TIC曲线整体呈速升-缓降型。结论MR及动态增强对复发性鼻咽纤维血管瘤的定位和定性诊断具有重要价值。