Neurofibromas of the head and neck

Twenty patients with neurofibromas of the head and neck have been observed for periods ranging from ten to 25 years. Seventeen patients had classical von Recklinghausen's disease. Of these, ten showed recurrence or appearance of new lesions after surgical resection, whether it was done during childhood or adulthood. While there is no known means of curing or even arresting neurofibromatosis, it is desirable to remove, as completely as possible, tumors which are deforming or symptomatic. Subsequent operations are often necessary to keep pace with the growth of the tumors. However, surgical resection, incomplete and imperfect as it may be, is extremely useful in improving the appearance, comfort and quality of life of these unfortunate patients.     

Hypercalcemia in squamous cell carcinoma of the head and neck

In a consecutive series of 771 patients with pathologically verified squamous cell carcinoma of the head and neck, 28 patients (3.6%) had hypercalcemia (greater than 11.0 mg/dl) during the course of their disease. The buccal mucosa (16/205, 7.8%) and tongue (8/148, 5.4%) were the most frequent primary sites. Most of the patients were stage IV patients with recurrence and advanced disease. The prognosis was poor with a median survival of only 6 weeks. The possible etiology of their hypercalcemia included humoral factors, bone metastases and independent primary lung cancer. The treatment of hypercalcemia was evaluated in 22 patients. Success was noted in all patients initially receiving chemotherapy (10 cases) or radiotherapy (3 cases) with or without saline hydration plus furosemide diuretics. However, the response rate in patients (9 cases) initially receiving hydration plus furosemide diuretics alone was 22% (2/9), with 4 of 7 failure cases later responding to chemotherapy. It is suggested that hypercalcemia be treated with chemotherapy or radiotherapy quickly, along with hydration plus diuretics. Also, the serum calcium level must be checked in patients with advanced buccal or tongue cancer.     

Modified and complete neck dissection in the treatment of squamous cell carcinoma of the head and neck

The relative merits and indications for complete or modified dissection of the neck are straightforward. Which operation is selected centers on the perception of the value of the preservation or the risk with the loss of one or more of three structures: the spinal accessory nerve, the internal jugular vein and the sternocleidomastoid muscle. If these were the only issues, the choice of operation would be easy. Unfortunately, some of the most contentious issues in treatment of metastasis to the neck have been linked with the concept of the modified neck dissection. Such issues as combined multimodality therapy, preoperative and postoperative radiation therapy or surgical treatment alone, prophylactic dissection and bilateral simultaneous dissection of the neck are rightly or wrongly tied in with the type of dissection of the neck. More information, such as the certainty of the real risk factors in the neck with metastatic disease, the real value, if any, of adjunctive combined therapy and basic information about the role of the nodes in the neck, is necessary before the debate on the modified versus the radical dissection of the neck will end.     

Uncoupling of excitation from contraction in uterine smooth muscle in near-term ewes

We infused forskolin in 30% ethanol or 30% ethanol systemically in seven chronically catheterized near-term sheep to determine the response of ovine uterine musculature to cyclic adenosine monophosphate stimulation. Maternal and fetal arterial pressure, fetal venous pressure, intrauterine pressure, and uterine electromyogram activity were monitored continuously. Prostaglandin E2 was infused at a delivery rate that caused a minimal 5 mm Hg increase in intrauterine pressure with definite contraction-like pressure spikes and associated uterine electromyogram activity. Forskolin (10 mg in 30% ethanol) or ethanol (vehicle) was then infused for 20 minutes. The prostaglandin E2 challenge was repeated 3 minutes later and again every 30 minutes over a 2 1/2-hour period. Data were analyzed by repeated measures analysis of variance. Infusion of ethanol (n = 2) had no apparent effect on either the intrauterine pressure or the uterine electromyogram response to prostaglandin E2 challenge. Forskolin infusion (n = 5) caused an attenuation of the intrauterine pressure response to prostaglandin E2 for 93 minutes. This effect was greatest 33 minutes after the infusion ended when the integrated pressure signal was 37% of the initial prostaglandin E2 response. The forskolin infusion had no effect on uterine electromyogram response to prostaglandin E2. We conclude that forskolin causes an uncoupling of excitation from contraction in the intact near-term ovine uterus.     

Femoral head preservation in non-united femoral neck fracture and head osteonecrosis in Cushing's disease.

There have been few reports associating avascular necrosis of bone with Cushing's disease. Patients with Cushing's disease and avascular necrosis of the femoral head usually receive total hip arthroplasty. However, hip prosthetic replacement in younger patients has been criticized due to a high incidence of component loosening. We report a case of successful femoral head preservation in non-united femoral neck fracture and head osteonecrosis in a 14-year-old girl with Cushing's disease (adrenocorticotropic hormone-secreting pituitary adenoma) who developed avascular necrosis of the right femoral head and pathologic fracture of the right femoral neck 2 years after the onset of hypercortisolism. Subtrochanteric valgus osteotomy was performed to preserve the femoral head after successful transsphenoidal surgery to remove pituitary microadenoma. At follow-up 10 years after the osteotomy, the femoral head had revascularized and the femoral neck fracture were united with much improvement of hip function. Dual energy X-ray absorptiometry scan of the right hip showed +0.86 SD from the normal bone densitometry. Aggressive femoral head preservation may be an effective alternative to treat this rare situation in a teenager.     

Action of galanin on smooth muscle strips isolated from rat and human uterus

OBJECTIVE: Galanin (Gal), a 29 amino-acid, peptide was isolated from porcine intestine extracts. Gal and its receptors are widely distributed in central and peripheral nervous systems, urogenital and gastrointestinal tracts of several mammalian species including the human. The study was undertaken to characterise the effects of Gal on uterus smooth muscle. MATERIAL AND METHODS: Smooth muscle strips were isolated from human uterus excised in perimenopausal age because of fibroids and prolapse. Another strips were taken from the uterus of a pregnant female rat a week before delivery. Muscle strips were suspended in the organ bath. Their spontaneous contractions and responses to Gal and oxytocin were recorded isometricaly. The changes in frequency and amplitude of smooth muscle contraction were analysed. RESULTS: Characteristics of smooth muscle stripes isolated from human uterus did not changed in the presence of Gal in concentration of 300 nM. Spontaneous contractions of smooth muscle stripes from the uterus of pregnant female rat were not affected in the presence of Gal in the concentration showed above, furthermore Gal did not alter contractions provoked by oxytocin. CONCLUSIONS: Gal has no influence on uterus smooth muscle function within perimenopausal age and the second half of pregnancy. The study does not exclude possibilities of Gal influence in other sex hormones profiles e.g. in young women or during labour.     

Neuropeptides in the regulation of female genital smooth muscle contractility

The mammalian female genital tract is innervated with nerve fibers containing vasoactive intestinal polypeptide (VIP), substance P, enkephalins and somatostatin. The effect of these peptides has been studied by in vitro tension recordings on smooth muscle preparations from the uterine body, cervix and Fallopian tube of eighteen women. Substance P (10(5) - 10(6) mol/l) had a dose-dependent stimulatory effect. VIP displayed a dose-dependently inhibitory effect on the substance P evoked contractions. Somatostatin, met-enkephalin and leu-enkephalin had neither stimulatory nor inhibitory effect. The findings suggest that substance P and VIP may participate in a dual nervous control of genital smooth muscle contractions.     

Three-dimensional structure of the smooth muscle in the term-pregnant human uterus

Objective: To identify the structural elements and describe the three-dimensional microanatomy of the term-pregnant human uterus.Methods: Biopsy specimens were taken from the funduses and the lower uterine segments of two term-pregnant uteri. Tissue was sectioned serially and stained with Masson trichrome. Microscope images were captured with a digital camera, aligned, and computer-processed. Computer-assisted three-dimensional reconstruction of structures was performed.Results: Five structures were identified: 1) fasciculus—the macroscopic organization of myocytes and connective tissue, 2) cylindric bundle—300 ± 100-μm diameter cylinder of densely packed myocytes, 3) sheet-like bundle—densely packed sheet of myocytes, 4) fiber bundle—a loosely packed bundle of small numbers of myocytes, and 5) communicating bridge—a large cylindric bundle that bridges adjacent fasciculi. The cylindric bundles merged, dichotomized, and intertwined with each other and with sheet-like bundles. Essentially all myocytes except those in fiber bundles were contiguous.Conclusion: The microanatomy of the term-pregnant human uterus contains clearly defined structural elements. These structures merge with each other and potentially form an interlacing network, connecting the vast majority of the myocytes of the uterus in a contiguous pathway.     

The significance of smooth muscle bundles in the endocervical submucosa

In approximately 25% of uterine cervices there are bundles of smooth muscle in the immediate submucosa of the endocervix usually in the region of the transformation zone. They are morphologically and immunohistochemically different from the inherent muscle deeper in the cervix in that they have more cytoplasm, are arranged in bundles not separated by collagen, and do not contain oestrogen or progesterone receptors. They are more commonly found during the reproductive years becoming less common after the menopause, but there is no association with parity, the use of exogenous steroids, uterine fibromyomas or uterine prolapse. At present it can only be concluded that their presence represents a morphological variation.     

Fine structure and innervation of smooth muscle in the monkey oviduct.

The smooth muscle of the monkey oviduct is similar to that described for other species and organs. Cell-to-cell contacts, in the form of simple appositions, were numerous. The adrenergic nerve supply was sparse, and close contacts between nerve and muscle were extremely rare. There was no difference in the density of innervation between the isthmus and ampulla. The rabbit appeared to have a greater denisty of innervation than the monkey.     

Non-selective cationic channels (NSCC) in smooth muscle cells from human umbilical arteries

The aim of our work was to investigate the presence of non-selective cation channels (NSCC) in freshly isolated smooth muscle cells from the human umbilical artery (HUA), one of the vessels involved in fetal-placental circulation. We studied the electrophysiological properties of NSCC using the patch-clamp technique in whole-cell configuration, and their possible role in the contractile state of intact vessels' rings. Recording with a high intracellular Cs(+) solution and a near physiological extracellular saline solution, we found a Gd(3+)-sensitive current (IC(50) = 1.05 microM) with a linear current-voltage relationship showing a reversal potential (E(rev)) of -2.1 +/- 1.2 mV (n =15 cells). La(3+) (100 microM) and Mg(2+) (5 mM) also blocked this current. In such conditions, inward currents were carried by Na(+) and Ca(2+); hence, a Na(+)-free solution inhibited only inward current (-67.3 +/- 11.4%, at -40 mV, n = 7, p < 0.05) and a Ca(2+)-Na(+)-free solution decreased the current even further with respect to values obtained in Na(+)-free solution (-69.8 +/- 8.8% at -40 mV, n = 9, p < 0.05). The permeability ratios (P(X)/P(Cs(+))) for monovalent and divalent cations were 1, 0.9, 0.7, 0.7, 0.7, and 0.5 where X = Cs(+), Na(+), Li(+), Ca(2+), Ba(2+) and Tris(+), respectively. In intact tissue, a 0 Ca(2+) extracellular solution, Gd(3+) (100-250 microM), La(3+) (200 microM) and Mg(2+) (5 mM) induced vasorelaxation in non-stimulated HUA rings.     

Histologic and chemical studies of the smooth muscle in the human cervix and uterus

This study compared chemical and histological measurements of the amount of smooth muscle in the human cervix to determine the extent of correlation of the 2 types of quantifications. Macroscopically normal uteri and cervical specimens from 31 nonpregnant women, aged 21-55 years, were studied. Histological estimates were made of muscle amount, and chemical measurements of actomyosin were made. It was seen that the mean muscle content of the cervix increased from the lower to the upward part. The smallest amount (6.4%) was in the lower cervix; midcervix muscle content increased to 18%; and upper was 28.8%. Chemically, the mean actomyosin content of the uterus was significantly greater than that of the cervix (7.54 vs. 3.72 mg/gm) (P=.01). The 2 types of measurements were correlated in their ability to quantitate muscle mass and amount in the human cervix.     

Resistance artery smooth muscle function in pregnancy and preeclampsia.

OBJECTIVE: The purpose of this study was to investigate whether the altered vascular resistance in pregnancy and preeclampsia results from alterations in intrinsic vascular smooth muscle properties or from external influences on vascular smooth muscle function. STUDY DESIGN: We studied subcutaneous resistance arteries from women with preeclampsia, from normal pregnant women, and from nonpregnant women, that were obtained during cesarean delivery or gynecologic surgical procedures, in a pressure myograph. Arteries were denervated, and smooth muscle cells were loaded with calcium indicator fura-2. Contractile properties were tested in physiologic saline solution and during potassium- and norepinephrine-induced constriction at various pressures. In addition, endothelial function was assessed. Intracellular calcium and tone were measured continuously. RESULTS: No significant differences in basal tone, constrictor, and myogenic responses were found between groups. Contractile element calcium sensitivity was significantly increased in women with preeclampsia. Norepinephrine caused an increase in calcium sensitivity in all groups. CONCLUSION: Vascular smooth muscle calcium sensitivity is increased in preeclampsia.