Diltiazem compared with hydrochlorothiazide in the treatment of mild-to-moderate essential hypertension

The efficacy of diltiazem (DTZ) (Tilazem; Parke-Davis) 90-180 mg twice daily was compared with that of hydrochlorothiazide (HCT) 25-50 mg once daily in the monotherapy of mild-to-moderate essential hypertension using a double-blind, double-dummy technique. Twenty-nine patients were randomly assigned to two groups and after a 4-week placebo period treated with HCT 25 mg once daily or DTZ 90 mg twice daily for 12 weeks. Dosage was doubled at week 8 in non-responders. Cross-over of therapy took place after a 4-week placebo washout. Both drugs effectively reduced raised arterial pressures with little change in pulse rate. HCT caused a slight elevation of the mean serum urate level. The study confirms that diltiazem offers an effective well-tolerated monotherapy for essential hypertension.     

Insulin-like growth factor I is required for the anabolic actions of parathyroid hormone on mouse bone.

Parathyroid hormone (PTH) is a potent anabolic agent for bone, but the mechanism(s) by which it works remains imperfectly understood. Previous studies have indicated that PTH stimulates insulin-like growth factor (IGF) I production, but it remains uncertain whether IGF-I mediates some or all of the skeletal actions of PTH. To address this question, we examined the skeletal response to PTH in IGF-I-deficient (knockout [k/o]) mice. These mice and their normal littermates (NLMs) were given daily injections of PTH (80 microg/kg) or vehicle for 2 weeks after which their tibias were examined for fat-free weight (FFW), bone mineral content, bone structure, and bone formation rate (BFR), and their femurs were assessed for mRNA levels of osteoblast differentiation markers. In wild-type mice, PTH increased FFW, periosteal BFR, and cortical thickness (C.Th) of the proximal tibia while reducing trabecular bone volume (BV); these responses were not seen in the k/o mice. The k/o mice had normal mRNA levels of the PTH receptor and increased mRNA levels of the IGF-I receptor but markedly reduced basal mRNA levels of the osteoblast markers. Surprisingly, these mRNAs in the k/o bones increased several-fold more in response to PTH than the mRNAs in the bones from their wild-type littermates. These results indicate that IGF-I is required for the anabolic actions of PTH on bone formation, but the defect lies distal to the initial response of the osteoblast to PTH.     

Case report 496

The opinions or assertions contained herein are the private views of the authors and are not to be construed as reflecting the views of The Department of the Army or the Department of Defense     

Recurrence of ovarian and uterine neoplasms: diagnosis with transrectal US

Twenty-one patients with clinically suspected recurrence of ovarian (n = 3) or uterine (n = 18) carcinoma were examined with suprapubic ultrasound (US) and transrectal US with high-frequency linear probes. The examinations were performed 3, 6, 9, and 15 months after surgery and radiation therapy. Eight patients underwent radiation therapy before surgery and ten after surgery; three underwent only surgery. Criteria for recurrence included increased anteroposterior diameter of the vaginal cuff (greater than 2.2 cm); structural alterations or presence of a mass in the vaginal cuff; and infiltration of the rectovaginal septum, bladder, and parametria. Transrectal US findings were true positive for recurrence in nine cases, true negative in ten, and false positive in two. US findings were true positive in three cases, true negative in seven, false positive in two, and false negative in three. In six cases results from US were technically poor, and no diagnosis could be made. Transrectal US was highly sensitive in detection of pelvic recurrent carcinomas, while US had little diagnostic value. The authors believe transrectal US can replace US in the evaluation of patients at risk for recurrent pelvic neoplasm.     

Neuropeptide Y: localization in the central nervous system and neuroendocrine functions

Neuropeptide Y (NPY) is a 36-amino acid peptide first isolated and characterized from porcine brain extracts. A number of immunocytochemical investigations have been conducted to determine the localization of NPY-containing neurons in various animal species including both vertebrates and invertebrates. These studies have established the widespread distribution of NPY in the brain and in sympathetic neurons. In the rat brain, a high density of immunoreactive cell bodies and fibers is observed in the cortex, caudate putamen and hippocampus. In the diencephalon, NPY-containing perikarya are mainly located in the arcuate nucleus of the hypothalamus; numerous fibers innervate the paraventricular and suprachiasmatic nuclei of the hypothalamus, as well as the paraventricular nucleus of the thalamus and the periaqueductal gray. At the electron microscope level, using the pre- and post-embedding immunoperoxidase techniques, NPY-like immunoreactivity has been observed in neuronal cell body dendrites and axonal processes. In nerve terminals of the hypothalamus, the product of the immunoreaction is associated with large dense core vesicles. In lower vertebrates, including amphibians and fish, neurons originating from the diencephalic (or telencephalic) region innervate the intermediate lobe of the pituitary where a dense network of immunoreactive fibers has been detected. At the ultrastructural level, positive endings have been observed in direct contact with pituitary melanotrophs of frog and dogfish. These anatomical data suggest that NPY can act both as a neurotransmitter (or neuromodulator) and as a hypophysiotropic neurohormone. In the rat a few NPY-containing fibers are found in the internal zone of the median eminence and high concentrations of NPY-like immunoreactivity are detected in the hypothalamo-hypophyseal portal blood, suggesting that NPY may affect anterior pituitary hormone secretion. Intrajugular injection of NPY causes a marked inhibition of LH release but does not significantly affect other pituitary hormones. Passive immunoneutralization of endogenous NPY by specific NPY antibodies induces stimulation of LH release in female rats, suggesting that NPY could affect LH secretion at the pituitary level. However, NPY has no effect on LH release from cultured pituitary cells or hemipituitaries. In addition, autoradiographic studies show that sites for 125I-labeled Bolton-Hunter NPY or 125I-labeled PYY (2 specific ligands of NPY receptors) are not present in the adenohypophysis, while moderate concentrations of these binding sites are found in the neural lobe of the pituitary. It thus appears that the inhibitory effect of NPY on LH secretion must be mediated at the hypothalamic level.(ABSTRACT TRUNCATED AT 400 WORDS)     

Blister Beetle Dermatosis in Hawaii Caused by Thelyphassa apicata (Fairmaire)

Members of the family Oedemeridae are known as false blister beetles. Although they have a worldwide distribution, oedemerid blister beetle dermatosis has been described only in the Pacific basin and the Caribbean. We report a case of the disorder in the Hawaiian Islands caused by Thelyphassa apicata (Fairmaire). To our knowledge this is the first case report described in that locale, and the first caused by this species.     

Transvaginal and transabdominal sonography: prospective comparison

Transvaginal (TV) and transabdominal (TA) sonography were compared in a prospective study. A total of 230 examinations (126 pelvic, 104 pregnancy) were performed on 215 patients, ranging in age from 14 to 80 years. The improved anatomic detail on TV scans yielded new information in 138 (60%) examinations and better visualization of pelvic structures in 51 (22%) examinations. There was no important difference in diagnostic information provided by the two imaging modalities in 36 (16%) cases, and TV images were worse in five (2%). The clinical diagnosis was altered on the basis of TV sonographic findings in 54 (24%) cases and confirmed with certainty in 166 (72%). Diagnostic problems posed by TA scanning were not resolved by TV scanning in ten (4%) instances. Statistical analysis indicated that TV scanning was significantly better than TA scanning in the visualization of gestational sac contents (P less than .005), detection of fetal heart motion (P less than .001), and evaluation of the endometrial canal in the retroverted or retroflexed uterus (P less than .001). TV scanning was significantly better than TA scanning in visualization of the ovaries in patients with uterine leiomyomas (P less than .005) but not significantly better in peri- and postmenopausal patients (P greater than .05).