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Biomedical subjects

M Kaplan

Publications and source records attributed to M Kaplan.

At least 271 records · Page 15Linked to original sources
PubMed1985

Larval and adult visual pigments of the zebrafish, Brachydanio rerio.

Photoreceptors of adult and larval zebrafish were assayed by microspectrophotometry to characterize their visual pigments, and to determine when the visual pigments first appear during development. Short single cone outer segments contained a pigment with a lambdamax near 417 nm. Long single cones and long members of double cone outer segments contained a pigment with a lambdamax near 480 nm. Short members of double cone outer segments contained a pigment with a lambdamax near 556 nm. Rod outer segments contained a rhodopsin with a lambdamax near 501 nm. All four visual pigment types found in adult photoreceptors were present in the earliest measurable larval photoreceptors.

Aging↗
PubMed1985

Serologic diagnosis of toxoplasmosis with emphasis on the detection of Toxoplasma-specific immunoglobulin M antibodies.

Commercially available kits were used for the detection of Toxoplasma-specific IgM antibodies. False positive IgM results were observed in whole sera containing Toxoplasma-specific antibodies together with rheumatoid factor when tested by immunofluorescence (IFA). False negative IgM results occurred in whole sera containing competing levels of Toxoplasma-specific IgG antibodies, as indicated by the IFA:IgM-M ratio. False positive and false negative IgM results often occurred when whole sera were tested. These false reactions were eliminated by fractioning IgM from IgG using the Isolab's IgM Isolation System. All five sera in this study with an IFA titer to Toxoplasma of greater than or equal to 1:16,384 also contained Toxoplasma-specific IgM antibodies. This suggests that sera with high titers to Toxoplasma should be tested for Toxoplasma-specific IgM antibodies.

Antibody Specificity↗
PubMed1985

Evaluation of testing modalities for peripheral neuropathy in lepromatous Hansen's disease.

To assess methods for detecting peripheral neuropathy, 28 previously untreated patients with lepromatous Hansen's disease underwent upper extremity manual muscle testing, sensory testing by using monofilaments, and electrophysiological nerve conduction studies (motor and sensory) at their initial examination. All but three patients demonstrated some abnormality identified by at least one of the testing procedures. Sensory testing with monofilaments located the greatest number of abnormalities found in 24 of the 28 patients. Next, electrophysiological testing demonstrated neuropathy in 21 of the 28 patients tested; 20 of these patients had sensory abnormalities and 20 had motor irregularities. The least sensitive method was manual muscle testing, which detected abnormalities in only 12 patients. Furthermore, sensory testing with monofilaments revealed peripheral neuropathy in 5 patients whose electrophysiological studies showed normal sensory patterns, and electrophysiological testing detected abnormalities in 1 patient whose sensory monofilament examination was normal. The results of this study support the usefulness of all three testing modalities.

Adult↗
PubMed1985

Controlled trial of dexamethasone in respirator-dependent infants with bronchopulmonary dysplasia.

A randomized trial was conducted of dexamethasone therapy in infants with bronchopulmonary dysplasia who were dependent on respirators and were not progressing clinically despite conventional treatment. Babies were admitted to the study if they had a roentgenogram and clinical diagnosis of bronchopulmonary dysplasia, were 2 to 6 weeks in age, weighed less than 1,500 g, had made no progress in weaning for the preceding five days, and were free of sepsis, patent ductus arteriosus, and congenital heart disease, and had had no intravenous fat for at least 24 hours. After parental consent was obtained, infants were randomly assigned to control or treatment groups. The study hypothesis was that with steroid treatment, babies could be weaned from the respirator within 72 hours and would show a significant improvement in lung compliance within that time. Sequential analysis exceeded criterion (P less than .05) when seven consecutive untied pairs showed weaning with dexamethasone and failure to wean in control infants. Pulmonary compliance improved by 64% in the treated group and 5% in the control group (P less than .01). No significant intergroup differences were noted in mortality, length of hospital stay, sepsis, hypertension, hyperglycemia, or electrolyte abnormalities. Study design permits the conclusion that dexamethasone can produce substantial short-term improvement in lung function, often permitting rapid weaning from the respirator, but long-term efficacy and safety must be demonstrated by further investigations.

Bronchopulmonary Dysplasia↗
PubMed1984

Frequent detection and isolation of cytopathic retroviruses (HTLV-III) from patients with AIDS and at risk for AIDS.

Peripheral blood lymphocytes from patients with the acquired immunodeficiency syndrome (AIDS) or with signs or symptoms that frequently precede AIDS (pre-AIDS) were grown in vitro with added T-cell growth factor and assayed for the expression and release of human T-lymphotropic retroviruses (HTLV). Retroviruses belonging to the HTLV family and collectively designated HTLV-III were isolated from a total of 48 subjects including 18 of 21 patients wih pre-AIDS, three of four clinically normal mothers of juveniles with AIDS, 26 of 72 adult and juvenile patients with AIDS, and from one of 22 normal male homosexual subjects. No HTLV-III was detected in or isolated from 115 normal heterosexual subjects. The number of HTLV-III isolates reported here underestimates the true prevalence of the virus since many specimens were received in unsatisfactory condition. Other data show that serum samples from a high proportion of AIDS patients contain antibodies to HTLV-III. That these new isolates are members of the HTLV family but differ from the previous isolates known as HTLV-I and HTLV-II is indicated by their morphological, biological, and immunological characteristics. These results and those reported elsewhere in this issue suggest that HTLV-III may be the primary cause of AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1984

Acute fatty liver of pregnancy. Survival with early cesarean section.

We have cared for two women with acute fatty liver of pregnancy in the past two years. Both patients survived as did three of babies. This compares with published mortality rates of up to 85% with this condition. Both patients presented with symptoms and signs of impending liver failure during the third trimester of pregnancy. Both patients were jaundiced, had elevated aminotransferases, leukocytosis, hepatic encephalopathy, and disseminated intravascular coagulation. The diagnosis was confirmed by liver biopsy in both. We attribute the unusually good outcome of these women and their children to early recognition of their disorder and prompt delivery once the diagnosis was considered.

Acute Disease↗
PubMed1984

Boar sperm cytoplasmic droplets: their ultrastructure, their numbers in the epididymis and at ejaculation and their removal during isolation of sperm plasma membranes.

Cytoplasmic droplets of the boar are progressively lost from the flagellum of boar spermatozoa during epididymal transit, at ejaculation and during the nitrogen cavitation technique for isolation of plasma membranes. Apparently very fragile, these structures are broken up in the fluids of the reproductive tract and in the buffer used during the nitrogen cavitation procedure. The maximal potential contamination of cytoplasmic droplet internal vesicular membranes in plasma membrane fractions was determined to be 2.2% of the entire membrane surface area collected. The highly sensitive silver-stained, two-dimensional (2-D) polyacrylamide (PAGE) gels of boar sperm plasma membranes did not reveal cytoplasmic droplet, internal membrane, marker polypeptides, further demonstrating the high purity of plasma membrane preparations. In addition, freeze-fracture demonstrates that the internal membranes of the cytoplasmic droplet show few intramembranous particles and these may contribute little protein to plasma membrane preparations. The presence of two forms of vesicular elements in boar sperm cytoplasmic droplets (typical vesicles and collapsed vesicles) is described.

Animals↗
PubMed1984

Improved prognosis in severely hypothermic newborn infants treated by rapid rewarming.

We introduced a rapid rewarming technique as part of standard therapy in 16 newborn infants with effects of severe environmental hypothermia. On admission, mean rectal temperature was 31.0 +/- 2.7 degrees C, mean gestational age was 33.4 +/- 4.5 weeks, and mean birth weight was 1.76 +/- 0.71 kg. Thirteen infants were admitted within 30 hours of delivery, and the remainder at 2 to 3 weeks of age. Infants were rewarmed under a radiant warmer. The mean time required to reach a rectal temperature of 36.5 degrees C was 3.96 +/- 2.37 hours. Major medical entities encountered included thrombocytopenia (eight patients), metabolic acidosis (eight), respiratory distress (eight), renal failure (six), apnea (four), patent ductus arteriosus (four), seizures (four), intracranial hemorrhage (three), infection (three), and necrotizing enterocolitis (two). No complications could be attributed to the rapid rewarming technique. Of three infants who died, all weighed less than 1.25 kg at birth. This 81% survival is in contrast to the high mortality (25% to 50%) noted previously among infants treated by gradual rewarming.

Apnea↗
PubMed1984

Evaluation of a gastric tube with esophageal balloon for neonatal use.

A gastric tube with esophageal balloon was designed for neonatal use. The response of the balloon was evaluated. In vitro studies involved comparisons of pressure changes (delta P) in a flask, as measured directly, or as transferred via the balloon. Values for delta P ranged frm 5 cmH2O to 40 cmH2O, and frequencies from 10 to 1620 cycles per minute. The volume of air within the balloon was varied from 0.1 to 0.4 ml. At each combination of pressure, frequency and balloon volume, the balloon transmitted an accurate, if minimally lower delta P, than that imposed. In a rabbit, intraesophageal delta Ps measured via the balloon were compared with intrapleural delta Ps, measured via a chest tube. The frequency rates and delta Ps achieved were similar to those encountered in the clinical situation. The delta s measured via the balloon were frequently equal to or sometimes minimally lower than the actual pleural pressure changes. The prototype meets recommended dimensions for esophageal balloon use in the neonate and allows for accurate routine measurements for calculation of pulmonary function. The device is now available commercially.

Animals↗
PubMed1984

Induction of immune alterations and successful renal transplantation with a simplified method of donor-specific blood transfusion.

We developed a new and simplified donor-specific blood transfusion (DSBT) protocol for prospective kidney transplant recipients from one-haplotype-mismatched related donors. Prospective kidney donors gave 450 ml of blood in a quad-pack unit, and the blood was stored in a blood bank. Twenty-five patients were transfused with 100 ml of the respective donor's whole blood at 1, 8, and 15 days after its storage. After DSBT, only three (12%) developed donor-specific lymphocytotoxic antibodies. Following DSBT, donor-specific mixed lymphocyte culture (MLC) was significantly suppressed, without any accelerated (secondary-type) response in early MLC. In addition, sera obtained after DSBT also suppressed donor-specific MLC significantly. Sixteen recipients subsequently received a kidney transplant from the donor, and all had functioning grafts at three months, but one lost the graft thereafter (graft survival rate: 94% at 12 months). This study indicates that (1) 100 ml of stored whole-blood DSBT three times at weekly intervals is a practical, less immunizing, and effective approach to enhance graft survival in recipients of a one-haplotype-mismatched graft; and (2) immune consequences of DSBT include induction of donor-specific cellular and humoral adaptive responses that might be conducive to successful graft outcome.

Adolescent↗
PubMed1984

A randomized trial of A.C.T. (asthma care training) for kids.

A randomized control trial of a curriculum, A.C.T. (Asthma Care Training) for Kids, was conducted. Seventy-six children between the ages of 8 and 12 years, whose asthma required treatment with medications at least 25% of the days per month, were randomly assigned to control and experimental groups. The control group received 4 1/2 hours of lecture presentations on asthma and its management. The experimental groups (consisting of four to seven children and their parents) received five 1-hour sessions comprising "the treatment." Children and their parents were interviewed before the sessions and 3, 6, and 12 months after the completion of the experimental treatment. Use of emergency rooms and hospitals was determined by reviewing the records of these patients (all members of the Los Angeles Kaiser Permanente health care system) for the period of 1 year before and 1 year after the treatment. Results include (1) equivalent increases in knowledge and changes in beliefs in both groups, (2) significant changes in the self-reported compliance behaviors of the experimental group only, and (3) significant reductions in emergency room visits and days of hospitalization among those receiving the experimental treatment, compared with the control group. These changes represent an estimated savings of approximately $180 per child per year for those in the experimental group.

Asthma↗
PubMed1983

Fasting and the precipitation of labor. The Yom Kippur effect.

We analyzed the effect of a 24-hour total food and water fast on the spontaneous onset of labor by studying the effect of the fast of Yom Kippur on Jewish pregnant women in Jerusalem. The mean baseline number of deliveries for our study period was 11.9 and 12.0 for 1981 and 1982, respectively. The number of deliveries on Yom Kippur was not significantly different from the mean. However, the number of deliveries for the 24-hour period after termination of the fast was 22 and 26 for 1981 and 1982, respectively. This difference attained statistical significance. While the clinical implications are not yet clear, a special risk may exist for women with a tendency toward early delivery should they undertake a 24-hour fast.

Fasting↗
PubMed1983

Early cardiac evaluation of thoracically conjoined twins.

Thoracopagus conjoined twins were delivered at 31 weeks gestation by cesarean section. Although there was a single heart, the possibility of salvaging one twin only was contemplated. Echocardiography revealed an A-V canal and suspected transposition of the great vessels. To determine the possibility of surgery, cardiac catheterization was performed to rule out other congenital cardiac malformations incompatible with life, and also to delineate the exact anatomy of the great vessels of the heart. Unfortunately, complex congenital abnormalities were found, thus excluding the possibility of surgery. Newly delivered conjoined twins should be regarded as potentially correctable and should be promptly investigated while they are yet in good clinical condition.

Female↗