Biomedical subjects
M Katz
Publications and source records attributed to M Katz.
Pseudotumour cerebri in SLE.
A 29 year-old woman with SLE was admitted to our department due to severe remitting headaches. Following investigation a high degree of intra cranial pressure was determined. Several years ago a similar finding was diagnosed, and the disease was brought into remission by the administration of periodical pulses of high dose intravenous immunoglobulins. Benign intracranial hypertension (BIH) is an uncommon presentation of neuro-psychiatric SLE. In this patient several risk factors of BIH (obesity, steroid therapy, and SLE) assembled and elicited a severe presentation of the disorder which became more resistant to therapy. Several pathogenic pathways tie BIH with SLE as thrombotic obliteration of cerebral arteriolar and venous systems and immune complex deposition within the arachnoid villi (that are responsible for CSF absorption). As shown in this care report of BIH, clinical findings do not always parallel various imaging techniques as MRI and CT brain scans.
Peripheral capillaroscopic findings and blood rheology during normal pregnancy.
Peripheral capillary microscopy and blood rheology where used to investigate circulatory changes during normal pregnancy. The first part of the investigation was designed as a cross-sectional study in which capillary morphology and blood flow in the first (n = 24) and third trimester (n = 15) of pregnancy was compared with non-pregnant controls (n = 15). In the second part a longitudinal comparison of capillaroscopic and hemorheological findings throughout pregnancy was performed in 12 women with four measurements at 10-week intervals. In addition, in this group hemorheological measurements were carried out. Both the cross-sectional as well as the longitudinal group showed a significant increase in capillary blood flow velocity which was already present in the first trimester. Throughout pregnancy a gradual enlargement of the pericapillar papilla was seen, reflecting water retention in the interstitial tissue. At low shear rates a significant increase in viscosity was found at the end of pregnancy both in whole blood and at a standardized hematocrit of 45%. Capillaroscopy appears to be an appropriate method to study circulatory changes throughout pregnancy and its value as a diagnostic tool to detect early pathological developments is the objective of a future investigation.
Breech presentation and cesarean section in term nulliparous women.
OBJECTIVE: To examine pregnancy outcome in nulliparous women with single term breech presentation. METHODS: Two departments of Obstetrics and Gynecology at the same hospital used different approaches to deliver nulliparous women with singleton breech presentation at term. One department (A) delivered by trial of labor and the other (B) delivered by elective cesarean section. Prospectively and blinded to obstetric condition, parturients were assigned to either department in a systematic alternate fashion. The study period covered 8 years (1985-1992). The pregnancy outcome parameters examined were: Apgar score, intra- and post-partum death and maternal and neonatal morbidity. Neonatal morbidity was classified in three major categories: non-neurological trauma, neurological signs and respiratory problems. RESULTS: The study included 264 women of whom 135 delivered in department A and 129 in department B. Department A had 35 vaginal and 100 cesarean births and department B 10 vaginal and 119 cesarean births. There was no intra-partum death and the only post-partum death occurred among vaginal deliveries. The Apgar score was significantly worse at 1 and 5 min in vaginally delivered babies of department B. Neonatal morbidity was significantly more frequent after vaginal births (P < 0.01). Maternal morbidity was significantly higher following cesarean sections (P < 0.01). Babies of vaginal deliveries had significantly higher non-neurological trauma (P < 0.01) and pathological neurological signs (P < 0.01) than those delivered by the abdominal route. CONCLUSION: The level of risk for mother and child in the nulliparous with term singleton breech, suggests cesarean section as the preferred route of delivery.
Hyperemesis gravidarum: epidemiologic features, complications and outcome.
During the period of 4 years between 1985 and 1988, 190 patients suffering from hyperemesis gravidarum (HG) were hospitalized at the Soroka Medical Center. From the 190 patients, 164 were followed up throughout their pregnancies and delivered at our Medical Center. The epidemiology of HG as well as the incidence of maternal complications and pregnancy outcome were analyzed and compared with 209 controls. The incidence of HG in our patient population was 6.3/1000 live births. The patients in the study group had fewer pregnancies and deliveries and more spontaneous abortions in the past than in the control population. Premature contractions and vaginal bleeding during the first trimester were more common among women with HG. Other complications of pregnancy were no more common than among controls. Women with HG in their current pregnancy had a lower incidence of spontaneous abortions (3.1%) as compared with previously reported rates in the general population (15%). Perinatal outcome was no different in women with HG than in the controls. Women with severe HG did not have statistically significant differences in the incidence of pregnancy complications and their pregnancy outcome was the same as in those without severe HG.
Chronic obstructive pulmonary disease in patients undergoing coronary artery bypass grafting.
The purpose of this study was to evaluate the effect of chronic obstructive pulmonary disease on patients undergoing coronary artery bypass grafting. Between June 1991 and June 1993, 651 patients underwent coronary artery bypass grafting: 37 patients (group I) had significant chronic obstructive pulmonary disease. These patients were compared with 37 matched control subjects (group II). Comparison of the groups was made with regard to postoperative morbidity and mortality. Quality of life of survivors was compared at the last follow-up. More patients in group I had preoperative arrhythmias (8 versus 1, p = 0.014). Group I patients had lower values of forced expiratory volume in 1 second (1.366 +/- 0.032 L versus 2.335 +/- 0.49 L, p < 0.0001), lower oxygen tension (63.5 +/- 8.2 versus 79.1 +/- 13.4 mm Hg, p = 0.001), and higher carbon dioxide tension (44.8 +/- 6.5 mm Hg versus 39.7 +/- 3.6 mm Hg, p = 0.001). After operation patients in group I had a longer hospital stay (8.1 +/- 3.6 days versus 6.6 +/- 1.7 days, p = 0.0236) and longer intensive care unit stay (2.64 +/- 0.9 days versus 1.23 +/- 0.49 days, p = 0.0001). More patients in group I required prolonged intubation (7 versus 1, p = 0.0278) and reintubation (5 versus 1, p = 0.088). More patients in group I had significant arrhythmias (27 versus 9, p < 0.0001). During a 16-month follow-up period, five patients in group I died, whereas none in group II died (p = 0.0271). Four deaths were related to arrhythmias. More group I patients were not functionally improved by the operation (17 versus 3, p = 0.0056). The results of coronary artery bypass grafting in patients with significant chronic obstructive pulmonary disease were not favorable in midterm follow-up. A major cause for morbidity and mortality was postoperative arrhythmias.
Prospects for funding of research in the twilight of our century.
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Cardiogenic cerebral emboli: diagnosis and treatment.
New technology has made it possible to identify cardiogenic cerebral emboli more easily and reliably. In recent years echocardiography, and in particular transesophageal echocardiography, has become the gold standard for the identification of cardiogenic sources of emboli, whereas transcranial Doppler is an important technique for the detection of cerebral emboli. Treatment strategies are better established and more accurate, if more complex, since the completion of large randomized trials. For primary prevention of stroke in elderly patients with nonvalvular atrial fibrillation, warfarin is generally indicated, yet in patients aged 60-75 years with no risk factors, aspirin may be sufficient. Warfarin is hazardous in older high-risk patients even at the 'low intensity' of the anticoagulation regimen; even lower doses are therefore being tested. Heparin and aspirin are indicated for short-term treatment of acute myocardial infarction, whereas for long-term treatment aspirin is still the drug of choice. However, if mobile left ventricular thrombi are present, warfarin is superior and new studies have shown its effectiveness for all myocardial infarction survivors. Combined treatment of warfarin and aspirin appears to be most effective in patients with mechanical prosthetic valves.
Clinical, ultrasound and hormonal markers of androgenicity in acne vulgaris.
Androgenic stimulation of sebaceous glands is an important factor in the development of acne. We examined 36 females (aged 14-34 years), selected because none had received oral contraceptives, anti-androgen therapy, or systemic antibiotics during the previous year, or isotretinoin therapy, prior to their participation in the study. Subjects were divided into groups on the basis of acne severity, as follows: physiological, mild and moderate. Only two patients had polycystic ovaries on ultrasound examination. Seven patients had irregular menses; none had evidence of hirsutism. We found that the severity of acne, based on the acne grade, was highly correlated with the inflammatory lesion count, and less correlated with the sebum excretion rate. Either acne grade or inflammatory lesion count could be related to some of the five androgenic hormone determinants; free testosterone (TESTOS), delta 4 androstenedione (DELTA 4), sex hormone binding globulin (SHBG), dehydroepiandrostenedione sulphate (DHEAS) and dihydrotestosterone (DHT). Multiple linear regression analysis determined the best model for predicting ACNE scores as involving DELTA 4 and DHEAS (positive effects), and SHBG (negative effect), P < 0.005, R2 = 0.36). In none of the patients were the levels of DHEAS or SHBG outside the normal range. The findings in the two patients with polycystic ovaries did not differ significantly from those in the remainder of the patients.
Downregulation of calcitonin receptor mRNA expression by calcitonin during human osteoclast-like cell differentiation.
Calcitonin inhibits both osteoclast formation and bone resorption, and is a primary treatment for patients with hypercalcemia and increased bone turnover. However, the clinical utility of calcitonin is limited because patients become refractory to calcitonin after several days (the calcitonin "escape phenomenon"). The molecular basis for calcitonin "escape" is unclear. To determine the regulatory mechanisms controlling calcitonin receptor (CTR) expression in osteoclasts and their precursors, we treated immature mononuclear precursors for human osteoclast-like multinucleated cells (MNC) formed in vitro with 1,25-(OH)2D3, to induce their differentiation to committed mononuclear precursors, and mature multinucleated osteoclasts, and used reverse transcriptase (RT)-PCR to assess expression of CTR mRNA in both committed mononuclear precursors and MNC. The PCR fragment produced was cloned and sequenced to confirm that it was derived from CTR mRNA. CTR mRNA expression was detected in mononuclear MNC precursors after 7 d of 1,25-(OH)2D3 treatment. It was also present in osteoclast-like MNC and highly purified giant cells from osteoclastomas, but not in monocytes or macrophage polykaryons formed in vitro. Calcitonin markedly decreased CTR but not actin mRNA expression in giant cells and MNC after 12 h, and removal of calcitonin restored CTR mRNA expression. Similarly, calcitonin decreased calcitonin-induced adenylate cyclase activity. These data suggest: (a) downregulation of CTR gene expression by calcitonin may in part explain the calcitonin "escape phenomenon"; and (b) expression of CTR mRNA occurs in mononuclear osteoclast precursors within 7 d after exposure to 1,25-(OH)2D3.
HIV seroprevalence and risk behaviors among lesbians and bisexual women in San Francisco and Berkeley, California.
Few data are available on human immunodeficiency virus (HIV) infection and risk behaviors among lesbians and bisexual women. A total of 498 lesbians and bisexual women was sampled from public venues in San Francisco and Berkeley, Calif, during 1993. The overall HIV seroprevalence was 1.2%. Ten percent of participants reported injecting drugs since 1978. Forty percent of the participants reported unprotected vaginal or anal sex with men during the past 3 years, including unprotected sex with gay and bisexual men and male injection drug users. The high rates of injection drug use and unsafe sexual behaviors suggest that lesbians and bisexual women frequenting public venues in San Francisco and Berkeley are at risk for HIV infection.
Radiative lifetimes of excitons in quantum wires.
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Seroprevalence of HIV and risk behaviors among young homosexual and bisexual men. The San Francisco/Berkeley Young Men's Survey.
OBJECTIVE: To estimate the prevalence of human immunodeficiency virus (HIV) infection and risk behaviors among young homosexual and bisexual men sampled from public venues in San Francisco and Berkeley, Calif. DESIGN: A survey of 425 young homosexual and bisexual men sampled from 26 locations during 1992 and 1993. Participants were interviewed and blood specimens were drawn and tested for HIV, level of CD4+ T lymphocytes, and markers of hepatitis B and syphilis. SETTING: Public venues in San Francisco and Berkeley, including street corners and sidewalks, dance clubs, bars, and parks. POPULATION STUDIED: Homosexual and bisexual men aged 17 to 22 years. MAIN OUTCOME MEASURES: Prevalence of HIV infection and risk behaviors. RESULTS: The HIV seroprevalence was 9.4% (95% confidence interval, 6.8% to 12.6%). The prevalence of markers for hepatitis B was 19.8% (95% confidence interval, 16.1% to 23.9%), and that for syphilis was 1.0% (95% confidence interval, 0.3% to 2.4%). The HIV seroprevalence was significantly higher among African Americans (21.2%) than among other racial/ethnic groups (P = .002). Approximately one third (32.7%) of the participants reported unprotected anal intercourse, and 11.8% reported injecting drug use in the previous 6 months. At the time of interview, 70.0% of the HIV-infected men did not know that they were HIV seropositive, and only 22.5% were receiving medical care for HIV infection. CONCLUSIONS: The prevalence of HIV infection is high among this young population of homosexual and bisexual men, particularly among young African-American men. The high rates of HIV-related risk behaviors suggest a considerable risk for HIV transmission in this population. Prevention programs and health services need to be tailored to address the needs of a new generation of homosexual and bisexual men.
Spontaneous abortion--high risk factor for neural tube defects in subsequent pregnancy.
An increased spontaneous abortion rate has been observed in pregnancies preceding that of fetuses or newborn infants with neural tube defects (NTDs). There are 2 suggested explanations for this observation. One is that a trophoblastic cell rest, remaining from a previous aborted pregnancy, interferes with normal embryogenesis. The second is that the previous lost fetus was affected with NTD. We studied the obstetric history of mothers of newborn infants with NTDs compared to those with other birth defects, in low and high risk groups for NTD (Jew and Bedouins). A significantly higher spontaneous abortion rate (48%) in the preceding pregnancy was found in the NTD group compared to the group with other birth defects (20%). This was especially remarkable for spina bifida cases in the Jewish study population. A significantly higher rate of preceding spontaneous abortion was also found in congenital heart defects (CHD) when compared to other congenital malformations. A hypothesis based on the multifactorial threshold model is put forward to explain these findings. Based on the realization that spontaneous abortion constitutes a high risk factor for NTD and possibly also CHD, we recommend a delay of subsequent pregnancy and periconceptional treatment with folic acid following spontaneous abortion.
The impact of fetal screening on indications for cystourethrography in infants.
To evaluate cystourethrography in the era of fetal screening, we evaluated retrospectively the clinical and imaging findings of all children up to the age of 1 year who underwent a cystourethrogram in a 5-year period (1987-1992). There were 292 children, 64 neonates (< 1 month, 51 boys, 13 girls) and 228 infants (1 month-1 year, 111 boys, 117 girls). Hydronephrosis detected prenatally and confirmed after birth by US was the indication for cystourethrography in 88 children (72 boys, 16 girls). This 4.5 to 1, male to female ratio is very unusual compared to children with urinary tract infection, the great majority of whom are girls. The findings based on imaging studies in these 88 children with hydronephrosis included 31 with vesicoureteral reflux (VUR) (in 4 this was secondary), 23 with obstruction at the ureteropelvic junction (UPJ), 13 with multicystic dysplastic kidney, 2 with obstruction at the ureterovesical junction, 1 with ectopic ureterocele and 1 with posterior urethral valves, both the latter without reflux. Eleven children had normal postnatal studies and six children were lost to follow-up. Urinary tract infection (UTI) was the indication in 163 children (62 boys, 101 girls). Forty-one children were examined for other causes. Although most cases of hydronephrosis were detected on fetal screening, UTI was still the most common indication for cystourethrography and some significant abnormalities were found in these symptomatic children.
Data shows medical nutrition therapy is cost-effective.
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Intrapartum fetal pulse oximetry: fetal oxygen saturation trends during labor and relation to delivery outcome.
OBJECTIVES: Our purpose was to study fetal arterial oxygen saturation trends by continuous pulse oximetry during labor in subjects with normal and abnormal delivery outcomes. STUDY DESIGN: Continuous fetal arterial oxygen saturation was measured during labor with a noninvasive reflectance pulse oximeter designed for fetal application. Averaged arterial oxygen saturation values were compared between stage 1 and stage 2 of labor, with stage 1 further subdivided into early (< or = 4 cm), middle (5 to 7 cm), and late (8 to 10 cm) phases. Delivery outcome was considered to be abnormal for any of the following conditions: gestational age < 37 weeks, maternal oxygen administration, delivery by cesarean section, 5-minute Apgar score < 7, umbilical artery pH < 7.10, birth weight < 2500 gm, or newborn intensive care unit admission. RESULTS: A total of 291 subjects were studied: 142 in Provo, 90 in Nijmegen and 59 in San Francisco. Subjects with delivery complications (n = 125) were evaluated separately from those with normal delivery outcomes (n = 160). Fetal arterial oxygen saturation was 58% +/- 10% (mean +/- SD) during the cumulative period of study for the normal-outcome group. A significant decrease (paired t test, p < 0.001) in fetal arterial oxygen saturation occurred from stage 1 (59% +/- 10%) to stage 2 (53% +/- 10%) labor. When stage 1 was subdivided into early (< or = 4 cm), middle (5 to 7 cm), and late (8 to 10 cm) phases, a gradual decreasing trend in fetal arterial oxygen saturation was observed: 62% +/- 9%, 60% +/- 11%, and 58% +/- 10%. CONCLUSIONS: With the use of reflectance pulse oximetry, a statistically significant decrease in fetal arterial oxygen saturation was observed during labor in women with normal and abnormal delivery outcomes.
Intussusception: a repeat delayed gas enema increases the nonoperative reduction rate.
The operative rate in intussusception has been significantly reduced by (1) expansion of the indications for attempted enema reduction of intussusception to include all children except those with peritonitis or septicaemia and (2) use of the gas (oxygen) enema rather than barium. This prospective study looked at the value of performing a delayed repeat gas enema in children in whom only partial reduction was achieved during the first enema, and who remained clinically stable. Twenty-one patients (of 156 with proven intussusception) had a repeat delayed gas enema, 30 minutes or more after the first attempt at reduction. This was successful in over 50%, reducing the number of patients requiring surgery at our institution by 24% and saving approximately five children a year from surgery.