Pisum lipoxygenase genes

The copy number, genomic arrangement and linkage relationships of two classes of lipoxygenase gene have been investigated in Pisum(pea) lines. Each of the two classes contained two to three members in P. sativum lines. RFLPs associated with genomic fragments containing the 5' sequences of one gene class permitted its correlation in genetical analyses with a lipoxygenase locus on linkage group 4, which was previously identified through polypeptide variation. Genetical analyses of RFLPs associated with other fragments identified by low- and medium-stringency hybridization to lipoxygenase cDNAs indicate the existence of other unlinked lipoxygenase gene loci.

A developmentally regulated early-embryogenesis protein in pea (Pisum sativum L.) is related to the heat-shock protein (HSP70) gene family

A cDNA clone, pCD7, was shown to hybrid-select from developing seeds of Pisum sativum L. an mRNA that translated into a polypeptide of apparent Mr 90 000. The translation product was observed only in the earliest stages of embryogenesis and was detected at a developmental stage when virtually all the cotyledon cells are mitotic. Sequence analysis of pCD7 showed it to correspond to a member of the 70 000-Mr heat-shock protein (HSP70) gene family. Transcripts corresponding to pCD7 were detected in different P. sativum organs, with roots apparently showing lower levels of pCD7-homologous RNA than other organs. Hybridizations to P. sativum DNA identified polymorphisms in the genomic DNA corresponding to pCD7 and the segregation of these in selected crosses indicated the existence of at least two genetic loci, one of which mapped to an existing linkage group.

Radiation regression patterns in treated retinoblastoma: 7 to 21 years later

A retrospective review of cases on file at the Ophthalmic Oncology Center of The New York Hospital-Cornell Medical Center, New York was performed in order to examine the appearance of radiation regression patterns 7 or more years after successful treatment of retinoblastoma with external beam radiotherapy. Forty-eight patients were found to have 89 tumors in 57 eyes which were treated solely with external beam radiation; they were followed for a minimum of 7 years and had sufficient information available for analysis. All but five of the patients had bilateral retinoblastoma. Seventy-four of the 89 tumors continued to be ophthalmoscopically visible after 7 or more years. Taking into account those that did change between the time of first evaluation (usually at the completion of treatment) and final evaluation (7 or more years after treatment), the number of Type I regressions increased by 10.1%, Type IIs decreased by 19.1%, Type IIIs fell by 7.8%, Type IVs rose by 10.1%, and the number of tumors that disappeared increased by 6.8%. Type II remained the most common regression throughout the follow-up. The regression with the greatest potential for change was the Type II regression. The pretreatment volume of the tumor correlated with long-term radiation regression patterns. The smallest tumors (mean size 1.1 dd [disc diameter] or less in size) completely disappeared, while the largest (mean 9.9 dd) became Type I regressions.

Is perinatal care in southwestern Ontario regionalized?

OBJECTIVE

To determine whether perinatal care in southwestern Ontario is regionalized, to identify trends over time in referral patterns, to quantify trends in perinatal death rates and to identify trends in perinatal death rates that give evidence of regionalization.

DESIGN

Cohort study.

SETTING

Thirty-two hospitals in southwestern Ontario (1 level III, 1 modified level III and 30 level II or I).

PATIENTS

All pregnant women admitted to the hospitals and their infants.

MAIN OUTCOME MEASURES

Antenatal and neonatal transfer status, live-born with discharge home alive from hospital of birth, stillborn, and live-born with death before discharge.

RESULTS

Between 1982 and 1985 the antenatal transfer rate increased from 2.2% to 2.8% (p less than 0.003). The proportion of births of infants weighing 500 to 1499 g increased from 49% to 69% at the level III hospital. The neonatal transfer rate increased from 26.2% to 47.9% (p less than 0.05) for infants in this birth-weight category and decreased from 10.2% to 7.1% (p less than 0.03) for infants weighing 1500 to 2499 g. The death rate among infants of low birth weight was lowest among those born at the level III centre and decreased at all centres between 1982 and 1985.

CONCLUSIONS

Perinatal care in southwestern Ontario is regionalized and not centralized; regionalization in southwestern Ontario increased between 1982 and 1985.

A copia-like element in Pisum demonstrates the uses of dispersed repeated sequences in genetic analysis

A DNA sequence between two legumin genes in Pisum is a member of the copia-like class of retrotransposons and represents one member of a polymorphic and heterogeneous dispersed repeated sequence family in Pisum. This sequence can be exploited in genetic studies either by RFLP analysis where several markers can be scored together, or the segregation of individual elements can be followed after PCR amplification of specific members.

Chemotaxis of bacteria in glass capillary arrays. Escherichia coli, motility, microchannel plate, and light scattering

Random and directed motility of bacterial populations were assayed by monitoring the flux of bacteria through a microchannel plate (a porous glass plate comprising a fused array of capillary tubes) separating two identical stirred chambers. Cells, washed free of growth medium by a new filtration method, were added to one chamber at a low density. Their number in the other chamber was determined from the amount of light scattered from a beam of a laser diode and recorded on a strip chart. Diffusion coefficients were computed from fluxes observed in the absence of chemical gradients, and chemotaxis drift velocities were computed from fluxes observed in their presence. Cells migrated through tubes of diam 10 microns more rapidly than through tubes of diam 50 microns, suggesting that the straight segments of their tracks were aligned with the axes of the smaller tubes. Mutants that are motile but nonchemotactic could be selected because they move through the microchannel plate in the face of an adverse gradient. Weak chemotactic responses were assessed from ratios of fluxes observed in paired experiments in which the sign of the gradient of attractant was reversed. Studies were made of wild-type Escherichia coli and mutants that are nonmotile, tumblely, smooth-swimming, aspartate-blind, or defective in methylation and demethylation. Chemotaxis drift velocities for the latter mutants (cheRcheB) were quite small.

Trace anesthetic gases during xenon arc photocoagulation for retinoblastoma

In pediatric ocular examinations, administration of continuous-flow anesthetic gases containing nitrous oxide, halothane, and oxygen enables the physician to do safe, controlled, reproducible examinations. We did a study in which the levels of waste anesthetic gases were measured during xenon arc photocoagulation procedures used for retinoblastoma. Waste nitrous oxide and halothane gases measured during these procedures significantly exceeded the levels recommended by the National Institute of Safety and Health. These high levels are of particular importance because of the physician's proximity to the patient during the procedure. The high levels of waste gases may have immediate deleterious effects on the physician's functioning capacity and may also pose long-term health hazards for the physician and operating room personnel.

Injection therapy for impotence

Injection of vasoactive drugs is an effective form of treatment for selected patients with impotence from virtually all causes. The two most commonly employed drugs in the United States are either papaverine alone or various combinations of papaverine and phentolamine. Patients with organic and mixed impotence are best suited for injection treatment, but selected patients with psychogenic impotence also benefit from therapy. After the patient is selected for injection therapy, he undergoes a series of trial injections in the physician's office. The incidence of priapism will be minimized if the initially administered doses are low and the patient is titrated to an appropriate dose level. Uncontrolled trials have revealed that injection treatment produces a satisfactory erection in 65 to 100 per cent of patients for a follow-up period of as long as 2 years with minimal side effects, but the dropout rate is high. If priapism does occur, it almost always responds readily to treatment with aspiration, low doses of an alpha-adrenergic agent, or both. The other common side effects are bruising or ecchymosis and nodule formation at the injection site. This latter complication has not been noted to cause significant abnormal penile curavature necessitating cessation of the program.

The effect of gabaculine on tetrapyrrole biosynthesis and heterotrophic growth in Cyanidium caldarium

Pigment synthesis in four strains of the unicellular red alga Cyanidium caldarium with different pigment-synthesizing patterns was inhibited in the presence of gabaculine (3-amino-2,3-dihydrobenzoic acid). Parallel inhibition of light-induced chlorophyll and phycocyanin synthesis was observed in strain III-D-2, which only synthesizes pigments in the light. Similar parallel inhibition was observed in the dark in mutant CPD, which is able to synthesize chlorophyll and phycocyanin in the absence of light. Inhibition of pigment synthesis in all strains was overcome by addition of 5-aminolaevulinic acid. Inhibition of phycocyanin synthesis in mutant GGB (unable to synthesize chlorophyll) and inhibition of chlorophyll synthesis in mutant III-C (unable to synthesize phycocyanin) were also observed. Gabaculine also inhibited the heterotrophic growth of C. caldarium in the dark. However, inhibition was overcome after an extended lag period, following which cell growth proceeded at a similar rate to that of control cells not exposed to gabaculine. Heterotrophic growth in cells pre-exposed to gabaculine was not inhibited by subsequent exposure. Possible mechanisms for this adaptation are discussed.

Diagnosis of Meleney's synergistic gangrene

A retrospective and comparative study of 127 case reports of Meleney's postoperative progressive synergistic gangrene and of 62 examples of postoperative amoebic skin gangrene, showed that these two entities were clinically indistinguishable and that therefore a purely clinical diagnosis of Meleney's gangrene could not be made. Furthermore, a critical appraisal of the bacteriological data indicated that a certain diagnosis of Meleney's gangrene cannot be provided by the clinical bacteriologist. Finally, the histological features were entirely non-specific thus precluding a definitive diagnosis by the histopathologist. If Meleney's entity cannot be diagnosed its existence becomes debatable. The alternative diagnosis of cutaneous amoebiasis is advanced for consideration. Several of the outstanding features of Meleney's progressive gangrene, hitherto unexplained, are better understood if Entamoeba histolytica is accepted as the prime cause rather than bacteria.

Cassava is not a goitrogen in mice

To examine the effect of cassava on the thyroid function of mice, we fed fresh cassava root to mice and compared this diet with low iodine diet and Purina. Cassava provided a low iodine intake and increased urine thiocyanate excretion and serum thiocyanate levels. Mice on cassava lost weight. The thyroid glands of mice on cassava were not enlarged, even when normalized for body weight. The 4- and 24-hr thyroid uptakes of mice on cassava were similar to those of mice on low iodine diets. Protein-bound [125I]iodine at 24 hr was high in mice on either the cassava or low iodine diets. The thyroid iodide trap (T/M) was similar in mice on cassava and low iodine diets. When thiocyanate was added in vitro to the incubation medium, T/M was reduced in all groups of mice; under these conditions, thiocyanate caused a dose-related inhibition of T/M. The serum thyroxine (T4) and triiodothyronine (T3) concentrations of mice on cassava were reduced compared with mice on Purina diet. Thyroid T4 and T3 contents of mice on cassava were relatively low compared with mice on Purina diet. Hepatic T3 content and T4 5'-monodeiodination in liver homogenates were reduced in mice on cassava compared with other groups. The data show that cassava does not cause goiter in mice. The thiocyanate formed from ingestation of cassava is insufficient to inhibit thyroid iodide transport or organification of iodide. The cassava diet leads to rapid turnover of hormonal iodine because it is a low iodine diet. It also impairs 5'-monodeiodination of T4 which may be related to nutritional deficiency. These data in mice do not support the concept that cassava per se has goitrogenic action in man.

Cutaneous amoebiasis: case report

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The prevalence of antibodies to Rickettsia rickettsii in an area endemic for Rocky Mountain spotted fever

A study of Rickettsia rickettsii was conducted in Rowan, Cabarrus, and Granville counties, North Carolina in an attempt to define the prevalence of endemic infection in this area. Serum samples were obtained from 1,976 healthy persons and tested by indirect hemagglutination for detectable antibodies to R. rickettsii. Of this group, 568 (28.7%) had detectable antibody (greater than or equal to 1:8), 80 (4%) had titers greater than or equal to 1:64, and 1,408 (70%) had no detectable antibody (less than or equal 1:8). Indirect immunofluorescence testing for antibody was also performed for 315 (15%) of the serum samples, of which 301 (95%) had undetectable titers and 14 (5%) had detectable titers ranging from 1:8 to greater than or equal to 1:64. Serological reactivity by indirect hemagglutination was detected in persons in the absence of known Rocky Mountain spotted fever. The study failed to show a good correlation of either the height of the geometric mean titer or percentage of seropositive persons with the previously determined age-related rates of acquisition of the disease. These data suggest that the antibodies measured may not be specific for R. rickettsii or that the antibody levels wane with time or both. It is probable that unrecognized infection occurs, but the true incidence or prevalence cannot be determined by available serological tests.

Epidemiology of Rocky Mountain spotted fever as determined by active surveillance

Prospective, active surveillance for Rocky Mountain Spotted fever (RMSF) was undertaken in two North Carolina counties for the years 1979-1981. Appropriate age, sex, and geographically matched controls were compared with the serologically confirmed cases of disease. Patients who were suspected of having infection, but were shown not to have RMSF, were also compared with the serologically proven cases. Ninety-eight cases were identified, and three of these patients died. The mean annual incidence of RMSF in these two counties was 14.59 cases/100,000 population. Identified cases occurred between the months of March and September. The overall mean annual incidence for men was 19.65/100,000 and for women 10.3/100,000. The study suggests that persons contracting RMSF are exposed to the vectors at their residences, which tend to be detached dwellings in woody, brushy areas. Children are more likely than adults both to be seen by physicians early in the illness and to be checked for ticks. Eighty-four percent of patients with serologically confirmed cases developed a rash. The epidemiology of RMSF in these two endemic counties is described.

Gastric sarcoidosis

Two cases of gastric sarcoidosis are reported. Both patients presented with a history suggestive of peptic ulceration and the diagnosis of sarcoidosis was made after operation.

Attrition in maintenance therapy for recurrent depression. A preliminary report

All maintenance treatment programs are complicated by the issue of patient noncompliance. This report investigates factors contributing to noncompliance during a 2-year study designed to evaluate the efficacy of long-term antidepressant medication in patients with recurrent unipolar depression. Only 21 of 51 patients (49%) who entered maintenance treatment successfully completed this phase of the study. Fifteen patients (8 completers and 7 dropouts) were randomly selected for an interview which focused on their previous psychiatric treatment history and attitudes towards the maintenance treatment program. In addition, these patients also completed a comprehensive personality battery. Results indicate that, while both groups had similar attitudes about the treatment program, they differed significantly along personality and psychiatric treatment history variables. Dropouts scored higher than completers on a measure of hysterical personality style. They were also more likely to have received psychotherapy in previous treatment experiences and to rate it as beneficial, while completers consistently rated prior treatment, which did not include antidepressant medication, as being of no benefit whatsoever. In order to enhance patient compliance, it is important to obtain information early in treatment about patients' treatment histories and their expectations about effective treatment for depression.

Detection of Rickettsia rickettsii antibodies in human sera by crossed immunoelectrophoresis

To identify Rickettsia rickettsii antigens of immunological importance, we examined sera from patients with serologically confirmed cases of Rocky Mountain spotted fever by crossed immunoelectrophoresis for antibodies to antigens extracted from the R strain of R. rickettsii with the detergent Triton X-100. Sixteen antigens were identified in the detergent extract by crossed immunoelectrophoresis with a hyperimmune rabbit serum raised against whole rickettsiae. When the rabbit antiserum was placed in the reference gel and patient sera were placed in the intermediate gel, antibodies to one or more antigens were detected in 61 of 71 North Carolina sera, all of 7 Oklahoma sera, and 9 of 10 Montana sera obtained from 1 day to 40 years after onset of Rocky Mountain spotted fever. Antibodies to antigens 1 and 16 were found as early as 1 day after onset of illness, and antibody to 16 was found in 20 of 29 sera obtained within the first 7 days of illness. Antibodies to antigens 2 and 3 generally did not appear until the third week of illness but were found in six of seven serum samples collected 4 to 40 years after onset of Rocky Mountain spotted fever. Antibodies to R. rickettsii antigens 1, 7, 8, and 16 were found in sera from patients with illnesses caused by other etiological agents. Four of the Oklahoma and Montana sera from Rocky Mountain spotted fever patients, but none of the North Carolina sera, had antibodies to antigen 12. Sera containing antibodies against antigens 3 and 14 prevented death of mice challenged with two 50% lethal doses of R. rickettsii.

Changes in plasma progesterone concentrations in mares treated with cloprostenol and human chorionic gonadotropin and inseminated during estrus

Daily changes in the plasma progesterone concentrations were determined in eight mares treated with intramuscular injections of 250 mug cloprostenol, a prostaglandin analogue, followed five days later by 2500 I.U. human chorionic gonadotropin. A second cloprostenol injection was given 14 days after the first; the mares were then inseminated on the third and fifth day of the subsequent estrus and a second injection of human chorionic gonadotropin was administered on the fifth day. The onset of estrus following the second cloprostenol treatment was synchronized beginning three to four days after treatment in all eight mares. All eight ovulated, five mares conceived and only four foaled. Evaluation of the progesterone profiles provided reliable indicators of luteolysis, ovulation and luteal function. Decreasing plasma progesterone concentrations were associated with cloprostenol induced luteolysis or preceded spontaneous onset of estrus. The plasma progesterone concentrations increased consistently after ovulation, and in the pregnant mares, the progesterone concentrations remained high during the first month after insemination.

Radical versus modified radical mastectomy for breast cancer

A prospective randomised trial (534 patients, 1969-75) was designed to determine whether radical mastectomy conferred advantages over modified radical mastectomy for breast cancer in terms of total survival, local recurrence, distant metastasis, and disease-free interval. The results showed no significant difference in outcome as regards these variables between the two treatments.

Acute pancreatitis associated with campylobacter infection

We report a case of acute pancreatitis associated with campylobacter infection. The patient presented with clinical symptoms and signs which suggested acute appendicitis. However, she was found to have acute pancreatitis with an acute campylobacter infection. Recent reports have shown that campylobacter is pathogenic in the biliary tract, and we suggest that it may also be responsible for some cases of acute pancreatitis in the absence of biliary disease.

Complications of anterior resection of the rectum using the EEA stapling device

Fifty patients had anterior resection of the rectum performed with end-to-end anastomosis using the EEA stapling device. The instrument certainly facilitated low anastomoses, but anastomotic dehiscence occurred in 3 cases, stenosis in 2, wound sepsis in 10, some degree os incontinence (usually only temporary) in 7 and anal fissure in 4 cases.

Benign and malignant struma ovarii

Three cases of struma ovarii are reported, two of which were benign, and one which was malignant. Immunoperoxidase studies confirmed that the tumors secreted triiodothyronine and thyroxine, but no carcinoembryonic antigen nor alpha-fetoprotein. In the case of the malignant struma ovarii, the patient's thyroid was histologically normal, and thus the possibility of a metastasis to the ovary from a primary thyroid carcinoma was excluded.

Anatomy of the retina of the mink (Mustela vison)

The retina of the normal pigmented mink has been studied by light and electron microscopy. This retina resembles the typical vertebrate retinia in its patterns of lamination and synaptic interconnectivity. Rod and cone outer segments and receptor spherule and pedicle endings are found. At least two different types of horizontal cell processes are seen with the electron microscope, suggestive of rabbit A and B types. Ribbon and conventional synapses are found in both plexiform layers; conventional synapses are also present in the inner nuclear layer. Quantitative studies of the inner plexiform layer revealed amacrine:bipolar synapse ratios (3.3:1) similar to those of the cat and monkey. Other quantitative parameters also resembled those previously reported for species with retinas that predominantly contain concentric-type receptive fields.

Rayleigh-gans-born light scattering by ensembles of randomly oriented anisotropic particles

A formula for the electromagnetic scattering amplitude is presented. Using the Rayleigh-Gans-Born approximation, we apply it to the alculation of Stokes matrices for ensembles of randomly oriented anisotropic particles. Two types of anisotropy are treated in detail: particles of any shape with a variable scalar refractive index n(r)delta(ij) and spherical particles with a constant tensor refractive index n(ij). For a monodisperse ensemble of the second type, we describe a method of extracting from data a shape parameter gamma. One may be able to generalize this method to yield structural information for a wider class of ensembles.