Tom D. Y. Chin

Developmental Changes in Myocardial Contractile Reserve in the Lamb

ABSTRACT: We have assessed serial changes in myocardial contractility and reserve in the normal lamb over the first month of life using an in vivo adaptation of the endsystolic pressure-volume relationship. Via a left thoracotomy, we insert a catheter tip pressure transducer into the left ventricle, affix an echo transducer onto the left ventricular epicardium, place an electromagnetic flow transducer around the pulmonary artery, and insert catheters for monitoring and infusions. We measure contractility by generating left ventricular wall stress-volume index (the cube of dimension) curves, at the same time increasing afterload by infusing phenylephrine. The slope of the endsystolic wall stress-volume index relationship is our index of contractility. Weekly studies were performed at rest and during isoproterenol infusion in 12 animals, and after propranolol administration in four. The data showed a progressive decrease in resting contractility but no change in maximal contractility during isoproterenol infusion over the 4 wk. Taking each week separately, the average increase in contractility during isoproterenol infusion was small at 1 wk (13%), moderate at 2 and 3 wk (24 and 26%, respectively), and large at 4 wk (79%). β-Adrenergic blockade with propranolol caused a significant decrease in contractility in three of four animals studied at 1 wk, in only one of four animals at 2 wk, and in none of four animals at 3 or 4 wk. Thus, the newborn lamb shows a limited reserve in contractility that increases progressively with age; the limited reserve appears secondary to a high resting β-adrenergic state.

Epidemic erythema infectiosum.

ERYTHEMA infectiosum is an apparently benign exanthematous disease commonly occurring in somewhat localized epidemics during the winter and spring months. The viral etiology has been assumed but ne...

Association of cervical cytomegaloviruses with venereal disease.

Abstract Parity, race, and use of oral contraceptive agents were not related to recovery of cytomegalovirus (CMV) from the cervix of 196 nonpregnant women, but CMV antibody was more prevalent among black women. Of 120 women examined because of suspected venereal disease, 16 (13.3 per cent) had cervical CMV infection, and seven (5.8 per cent) had cervical herpesvirus infection. Neither virus wag recovered from 76 women having routine examinations. CMV isolation and antibody were significantly more prevalent among those with documented past or active gonococcal infection, but CMV isolation did not correlate with the actual presence of Neisseria gonorrhoeae in the cervical secretions at the time of sampling. The study suggests, but does not prove, an association between cervical CMV infection and venereal disease in this population. (N Engl J Med 288:932–934, 1973)

Prevalence of aneuploidy, overexpressed ER, and overexpressed EGFR in random breast aspirates of women at high and low risk for breast cancer

SummaryBreast tissue biomarkers which accurately predict breast cancer development within a 10 year period in high risk women are needed but currently not available.We initiated this study to determine 1) the prevalence of one or more breast tissue abnormalities in a group of women at high risk for breast cancer, and 2) if the prevalence of biomarker abnormalities is greater in high risk than in low risk women. Eligible high risk women were those with a first degree relative with breast cancer, prior breast cancer, or precancerous mastopathy. Low risk women were those without these or other major identifiable risk factors. Ductal cells were obtained via random fine needle aspirations and cytologically classified. Biomarkers included DNA ploidy, estrogen receptor (ER), and epidermal growth factor receptor (EGFR).The prevalence of DNA aneuploidy was 30%, overexpression of ER 10%, and overexpression of EGFR 35%, in the 206 high risk women whose median 10 year Gail risk (projected probability) of developing breast cancer was 4.5%. The prevalence of aneuploidy and overexpressed EGFR was significantly higher in the high risk women than in the 25 low risk controls (p < 0.002), whose median 10 year Gail risk was 0.7%. The difference in the prevalence of ER overexpression between high and low risk groups was not statistically significant (p = 0.095). This may be due to the low prevalence of overexpressed ER and the small number of controls. A significant difference was noted in the prevalence of one or more abnormal biomarkers between the high risk and low risk women (p < 0.001).A large prospective trial is needed to determine if one or more of these biomarkers, is predictive of breast cancer development.

Epidemic Infection with Coxsackie Virus Group B, Type 5

A SEPTIC meningitis was a term coined in 1924 by Wallgren,1 who believed that he was describing a distinct etiologic entity. Since that time, aseptic meningitis has been shown to be due to varied c...

Brain Cancer in a Residential Area Bordering on an Oil Refinery

Both in response to community concerns about brain cancer related to an oil refinery and in order to more fully understand the etiology of primary site brain cancer (glioma), a highly focused cancer cluster investigation was conducted. The components included: (1) a literature review of occupational exposures in the petroleum refining and petrochemical industries, (2) comparisons between observed and expected cases, (3) comparisons between mean age at diagnosis and median survival time and (4) interviews concerning exposures of cases. Evidence from the literature review revealed little, if any, effect of petroleum refinery or petrochemical exposure on the risk for brain cancer. There was no statistically significant increase in the number of brain cancer cases in the community (observed = 12, expected = 9.46, standardized mortality ratio = 1.27). There was no statistically significant decrease in mean age at diagnosis or median survival time among those most exposed. Reports of exposure from the case interviews were highest for eating processed meats (98.5%), dental X-rays (96.6%), dog ownership (91.2%) and swimming (80.3%). There were no major occupational exposures identified. It seems unlikely that petrochemicals are involved in any significant way in the etiology of most brain cancers (gliomas). A follow-up case-control study should focus primarily on those risk factors mentioned frequently by the cases.

Previous and simultaneous cancers in patients with leukemia

Abstract In a 5-yr leukemia surveillance program in the Kansas City area, 31 of 455 leukemic adults were observed with a past or concurrent history of another malignancy. The frequency of occurrence of nonhematologic malignancies in these 31 patients did not represent any increase over that expected in a general population. After the onset of leukemia, particularly CLL, there may possibly be an increased risk of developing another primary malignancy. To further determine a susceptible population, future studies should concentrate on the patients immune capabilities and histocompatibility status. Investigators should always consider the sequence of cancer occurrence in analyzing any data.

Ecological and epidemiological studies of histoplasmosis in the United States of America.

Histoplasmosis is a disease that is transmitted from nature to man. The causative agent,Histoplasma capsulatum, grows freely in the soil and the infection is spread by inhalation of the infectious spores. The infection is highly endemic in the central United States. Soil contaminated with fecal droppings of chickens, starlings, blackbirds, and other avian species is a principal source of infection.

Epidemiologic studies of type B influenza in 1961-1962.

DURING the winter of 1961-1962 influenza outbreaks were reported in several states of the Middle West. Etiologic studies on several of the outbreaks incriminated Type B influenza virus as the primary causative agent. This virus was isolated from pharyngeal washings of patients in Jefferson City, Potosi, Marshall, and Kansas City, Mo.; Kansas City, Kans.; Lawrence, Kans.; Hazleton, Iowa; and Grand Tower in southern Illinois. Intensive epidemiologic studies were carried out on the sharply localized outbreaks in Potosi, Mo., and Hazleton, Iowa. This report will describe some of the observations made on these two outbreaks. Particular reference will be made to the occurrence of the infection among school children and the spread of the infection to their family contacts.

Paralytic Disease Due to Infection with Echo Virus Type 9

DURING the past two years infections with ECHO virus Type 9 have been widespread in the United States. In 1957 they appeared in epidemics in Minnesota1 and in Wisconsin.2 Their prevalence in the Bo...