Re-operation due to severe late-onset persisting groin pain following anterior inguinal hernia repair with mesh.

OBJECTIVES: Mild pain lasting for a few days is common following mesh inguinal hernia repair. In some patients however, severe groin pain may appear months or even years postoperatively. The aim of this study was to report our experience of late-onset persisting severe postoperative groin pain occurring years after mesh hernioplasty. METHODS: In a 9-year period, 1,633 patients (1,073 men), median age 63 years (range 19-88), underwent mesh groin hernia repair. Between 1.5 and 4 years postoperatively, six patients (0.35%) presented with severe chronic groin pain unrelieved by conservative measures and surgical exploration was essential. The patients' records were retrospectively reviewed for the purpose of this study. RESULTS: Ilioinguinal nerve entrapment was detected in four patients. The meshes appeared to be indistinguishable from the nerve and were removed along with the stuck nerve. New meshes were properly inserted. Mesh fixation on the periostium of the pubic tubercle by a staple was found in the other two patients. The staples were removed from the periostium in both patients. Neither hernia recurrence nor chronic groin pain was persisting in all six patients during a follow-up of 6-44 months postoperatively. CONCLUSION: From the results of this study, it appears that ilioinguinal nerve entrapment and/or mesh fixation on the periostium of the pubic tubercle are the causes of late-onset severe chronic pain after inguinal mesh hernioplasty. Mesh removal, along with the stuck ilioinguinal nerve and staple detachment from the periostium, are the gold-standard techniques if conservative measures fail to reduce pain.

Surgical treatment of acetabular posterior wall fractures.

This is an analysis of 52 fractures of the posterior wall of the acetabulum treated operatively and reviewed 2-15 years after injury. In 48 cases the fracture was associated with posterior dislocation of the hip, which was treated by closed reduction soon after the injury. In all but two of the cases there was a displaced single or comminuted fragment resulting in a large defect in the posterior acetabular wall; they were treated by open reduction and internal fixation to restore joint congruity and stability. In the remaining two cases, the fragment was small but trapped in the joint and was excised. A strict correlation was found between accurate reduction of the fracture and the clinical and radiological results, which were excellent or very good in 85 per cent and 87.5 per cent of the patients, respectively. Surgical and late complications were peroneal palsy in four patients, ectopic ossification restricting hip movement in two cases, aseptic necrosis in three, and osteoarthritis in another three cases.

Two distinct types of intraneuronal neurofibrillary tangles highlighted by polarized light after silver impregnation with a modified Bielschowsky method.

Neurofibrillary tangles (NFTs) are one of the morphological hallmarks of Alzheimer's disease. The birefringency and dichroism of NFTs following congo red staining have long been known. Herein, we report the observation that a subset of NFTs show distinct birefringency induced by a modified Bielschowsky silver impregnation method. Birefringency of NFTs could not be elicited after silver impregnation with one other version of the Bielschowsky method or with the Bodian technique. To our knowledge, these properties of NFTs after metal impregnation have not been previously documented.

Permanent alterations in the hypothalamic-pituitary-thyroid axis in the rat following phenytoin exposure in utero.

Phenytoin exposure in utero results in permanent alterations of the hypothalamic-pituitary-thyroid axis in the rat. The DPH exposed animals have decreased weight gain, thyroxine and triiodothyronine concentrations. In addition, they have blunted thyroid-stimulating hormone responses to thyrotropin-releasing hormone, propylthiouracil challenge or thyroidectomy. The diminished pituitary response in these animals is similar to that reported in neonatal thyrotoxicosis in the rat. This may be due, in part, to structural similarities between phenytoin and the thyroid hormone.

Dilantin and salicylate effects on hepatic thyroxine bio-availability and dialyzable thyroxine.

Earlier studies have shown that drugs such as dilantin inhibit T4 binding by thyroid hormone binding globulin (TBG) and cause a displacement of T4 from TBG to prealbumin with no change in the albumin-bound T4 fraction. Since recent studies have shown albumin-bound T4 is freely transported into liver, the present studies are designed to investigate drug effects on T4 transport in liver. The effect of salicylate and diphenylhydantoin (Dilantin) on T4 in human serum were examined both in vitro by using equilibrium dialysis and in vivo in the rat liver by using a tissue sampling single injection technique. Serum was obtained from 6 healthy normal volunteers and was made either 0 or 0.5 mM Dilantin and either 0 or 10 mM sodium salicylate. The portal vein injection vehicle contained 125I-T4/3H-water (highly diffusible internal reference) mixed with either a) Ringer's (0.1 g/dl albumin), b) 5% T4 antiserum, or c) 80% human serum. The free dialyzable fraction in vitro was raised by 40 and 125% after the addition of Dilantin and salicylate respectively. However, the percent of total T4 that was transported into liver on one pass, 17 +/- 1%, was not different in the control, the salicylate treated, or the Dilantin-treated sera. Therefore, in contrast to the in vitro dialyzable measurement of free T4, which is elevated by toxic concentrations of Dilantin or salicylate, the bio-available fraction of T4 as determined by the single pass perfusion technique, is unchanged in rat liver in vivo. These drug-induced changes in free T4 in vitro and bio-available T4 in vivo are similar to the ones reported previously in non-thyroidal illness.

Ultrastructural evidence that insoluble microtubules are components of the neurofibrillary tangle.

The ultrastructure of Alzheimer's neurofibrillary tangles is heterogeneous and includes abnormal paired helical filaments (PHF) and various other insoluble structures. Insoluble non-PHF components isolated from neurofibrillary tangles were examined by electron microscopy. Comparison of these fractions with normal assembled neurofilaments and normal brain microtubules revealed scattered profiles which were morphologically (not chemically) identical to structures present in the microtubule, but not in the neurofilament preparations. These results support the notion that insoluble microtubules contribute to the make up of the neurofibrillary tangle. Based on these findings, preliminary experiments were conducted which suggest that non-enzymatic glycosylation may be a pathway leading to insolubility of the microtubules.

Effects of phenobarbital on hypothalamic-pituitary-thyroid axis in the rat.

It has been reported that phenobarbital (PB) increases the peripheral clearance of T4 and T3 and decreases serum T4 and T3 concentrations in the rat, but serum TSH remains unchanged. To explore a possible direct effect of PB on TSH secretion at the hypothalamic-pituitary level, adult male rats were given PB 100 mg/kg or vehicle IP for 10 days. No difference in their thyroid weights was observed. In the PB-treated group serum T4 was decreased (PB, 3 +/- 0.2 micrograms/dl vs. control, 3.8 +/- 0.1 micrograms/dl, mean +/- SE, p less than .002), as was serum T3 (PB, 51 +/- 6 ng/dl vs. control, 70 +/- 5 ng/dl, p less than .05), but serum TSH remained unchanged. Pituitary TSH and hypothalamic TRH contents also were unchanged. Further studies were carried out similarly in the thyroidectomized hypothyroid rat to eliminate the effect of PB on serum T4 and T3 levels. PB or vehicle were started two days after thyroidectomy. By postoperative day 12, TSH levels in the PB-treated rats were lower than in the controls (PB, 697 +/- 62 microU/ml vs. control, 891 +/- 53 microU/ml, p less than .05). Pituitary TSH and hypothalamic TRH contents again were similar in both groups. When TRH (500 ng/kg body weight, IV) was given, the increment in serum TSH at 10 minutes was significantly lower in the PB group (PB, 53 +/- 26 microU/ml vs. control, 131 +/- 18 microU/ml, p less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Somatostatin is a regulator of thyrotropin secretion in the perinatal rat.

The perinatal rat exhibits low serum TSH levels in the presence of very low concentrations of T3 and T4. We had reported previously that this animal does not require endogenous TRH for TSH release. We investigated here whether the inhibitory hormone somatostatin (SS) has a role in maintaining the low TSH secretory set-point. To study the effect of SS in the immature model, we passively immunized pregnant rats with SS antiserum to neutralize endogenous SS. Acute iv administration of 0.3 ml SS antiserum to pregnant rats (day 20 of pregnancy) resulted in a significant serum TSH elevation in both mother and fetus 60 min after injection compared to the control values [maternal TSH, 62 +/- 6 muU/ml vs. control, 43 +/- 4 (mean +/- SE; P less than 0.05); fetal TSH, 95 +/- 8 vs. control, 66 +/- 6 (P less than 0.02)]. The binding capacity of the AS in the fetal serum far exceeded the circulating SS in the fetus. Similar results were obtained when neonates 5 and 10 days of age were injected with 0.1 ml AS, ip. Further experiments were done with the use of synthetic SS. Acute iv injection of synthetic synthetic SS (1 microgram) to pregnant rats made hypothyroid by feeding of a low iodine-propylthiouracil diet for the last week of gestation suppressed the elevated serum TSH level in both mother and fetus 15 min after the injection [maternal TSH, 102 +/- 11 vs. control, 163 +/- 22 (P less than 0.05); fetal TSH, 99 +/- 9 vs. control, 143 +/- 13 (P less than 0.02)]. Similar results were obtained when hypothyroid neonates 5 and 10 days of age were injected with 1 microgram SS, ip. These findings suggest that there is similarity in the effects of SS on TSH secretion (suppression) in mother, fetus, and neonate and dependence of the perinatal TSH on SS, in contrast to TRH. It is, then, likely that TSH secretion in the perinatal rat is under the inhibitory influence of endogenous SS.

Thyrotropin releasing hormone biosynthesis in neonatal rat pancreas.

We studied the in vitro synthesis of thyrotropin releasing hormone (TRH) by pancreatic cells, using [14C]histidine incorporation and radioimmunoassay. Neonatal pancreases were incubated in Krebs-Ringer-bicarbonate buffer, pH 7.4, at 37 degrees C, under 95% O2-5% CO2. [14C]histidine was added and its incorporation into the tissue proteins was followed up to 4 hours. The methanolic pancreatic extracts obtained were subjected to Sephadex G-200 chromatography. Two peaks of [14C] radioactivity were eluted, one small (20% of total radioactivity) with the void volume and one large in a position identical to synthetic TRH. Both radioactive peaks corresponded to immunoreactive TRH peaks present in the same samples. In pulse-chase experiments, excess cold histidine was used and samples taken showed again similar radioactive peaks with an initial increase and a later decrease in the size of the small peak. We conclude that the neonatal rat pancreas actively synthesizes TRH and/or a higher molecular weight TRH-like protein, which may represent a TRH precursor.

Regulation versus modulation in GnRH receptor function.

Serum luteinizing hormone (LH) concentration after exposure to gonadotropin-releasing hormone (GnRH) indicates that an instantaneous increase occurs in the rate of release of LH directly from the anterior pituitary, as measured dynamically during superfusion in vitro. On the other hand, estradiol-17 beta (E2) alone shows no such instantaneous effect on LH release rate (at least for the first four hours), in either physiologic or pharmacologic concentrations. At the same time, brief (ten to 30 minute) exposure of isolated anterior pituitary plasma membranes to physiologic concentrations of E2 significantly alters the binding of a fully biologically active 125I-GnRH to its plasma membrane receptor protein. In order to characterize the effect of E2 on GnRH binding further, we preincubated dispersed bovine anterior pituitary cells for six hours in the presence or absence of physiologic concentrations of E2 (10(-10)M). Following preincubation in the presence of E2, the cell suspension was incubated for 30 minutes with physiologic concentrations (5 X 10(-11) - 5 X 10(-10)M) of a fully biologically active 125I-GnRH. The treatment, at least, doubled the number of biologically important high affinity GnRH binding sites (Kd's = 7.5 X -10(-11) - 4.5 X 10(-10)M), and changed the binding capacity of some of the binding sites up to three fold, which altered the cooperativity of GnRH-receptor interaction. Thus, the interaction of E2 with GnRH at the level of GnRH receptor is mandatory for the short-term pituitary effect of E2 on LH release in vitro and in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)

Localization of putative gonadotrophin releasing hormone receptor protein in the anterior pituitary.

Specific binding of a fully biologically active 125I-gonadotrophin releasing hormone (GnRH) to isolated anterior pituitary cells is time dependent, saturable and the concentration dependent binding curves exhibit positive cooperativity. Binding to intact or solubilized plasma membranes and an affinity purified GnRH receptor protein reveals in all instances multiple high affinity binding sites. Thus, GnRH receptor protein appears to be an intrinsic constituent of the cell membrane, and perhaps, other membranous organelles. To investigate the latter, the binding of 125I-GnRH to various subcellular fractions was studied and its affinity and time requirements determined. GnRH binding to plasma membranes and secretory granules was to multiple high affinity sites, while that to nuclei and microsomes was to a single high affinity site. Binding was 1.83 +/- 0.07, 0.78 +/- 0.04, 0.31 +/- 0.03 and 0.27 +/- 0.03 fmol micrograms-1 protein for isolated plasma membranes, secretory granules, microsomes and nuclei, respectively, after 30 min incubation with 10(-9) M GnRH. The magnitude of binding to microsomes did not change during the incubation period. It did not show any decrease (p greater than 0.05) in isolated nuclei and plasma membranes, except for the 24 h time period, when a significant drop (p less than 0.001) was seen. Binding to the secretory granule fraction culminated at 15 min and then decreased (p less than 0.001) steadily to a non-detectable level at 24 h. Thus GnRH receptor protein or its portion may be an integral part of some membranous particles in the anterior pituitary cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of diphenylhydantoin on hypothalamic-pituitary-thyroid function in the rat.

Chronic diphenylhydantoin (DPH) administration (5 mg x 100 g body wt-1 x day-1) to the normal rat is associated with a decrease in the serum thyroxine (T4) and triiodothyronine (T3) concentrations without an appropriate rise in the serum thyrotropin (TSH) concentration, suggesting a possible direct effect of DPH on TSH secretion. To further study this possibility, DPH was administered chronically to thyroidectomized, hypothyroid rats. In the hypothyroid rats treated chronically with DPH, serum TSH did not increase, pituitary TSH content was significantly decreased, and the serum TSH response to thyrotropin-releasing hormone (TRH) was decreased compared to that of diluent-treated, hypothyroid rats. Hypothalamic TRH content was similar in DPH and diluent-treated rats. These findings suggest that DPH suppresses pituitary TSH secretion, probably as a thyroid hormone agonist. The effect of a single large dose of DPH (20 mg/100 g body wt) administered to thyroidectomized rats also decreased serum tSH but, in contrast to the findings in chronically treated rats, hypothalamic TRH and pituitary TSH content and the serum TSH responses to TRH were increased. These differences may be due to the acute inhibitory effect of a large dose of DPH on hypothalamic TRH release. Furthermore, because the effect of thyroid hormone on regulating pituitary TSH synthesis and release is dose and time dependent, the effect of DPH as a thyroid hormone agonist on pituitary TSH dynamics may also be variable.

Iodide-induced hypothyroidism: a potential hazard during perinatal life.

The administration of iodide to pregnant and nursing rats induces hypothyroidism in the term fetus and neonatal rat through age 10 days as indicated by an increase in the serum concentration of thyroid-stimulating hormone and a decrease in the serum of thyroxine and triiodothyronine. Thyroid function returned to normal from age 18 through 60 days in spite of continued iodide administration, strongly suggesting that resistance to the inhibitory effect of iodide on thyroid hormone synthesis is developed at approximately 18 days of age. This perinatal rat model can be used to study the mechanisms responsible for iodide-induced hypothyroidism and goiter in human newborns whose mothers received iodide-containing medications during pregnancy.

Thyrotropin-releasing hormone is not required for thyrotropin secretion in the perinatal rat.

To determine the role of thyrotropin-releasing hormone (TRH) in the regulation of thyroid-stimulating hormone (TSH) secretion in the perinatal period, a physiological approach of neutralizing circulating TRH in the fetal and early neonatal rat was employed. TRH-antiserum (TRH-AS) raised in rabbits and administered daily to low iodine-propylthiouracil (LID-PTU)-fed pregnant rats from days 12 to 19 of gestation markedly impaired the rise in serum TSH to LID-PTU when compared with normal rabbit serum-treated controls. In contrast, fetal serum TSH was unaffected by TRH-AS. The binding capacity of TRH-AS in the fetal serum (111 ng/ml) far exceeded circulating TRH in the fetus. Similarly, acute TRH-AS administration to the pregnant rat fed LID-PTU markedly decreased the serum TSH concentration in the mother, but not in the fetus, 60 min after TRH-AS administration. Chronic TRH-AS administration to neonatal rats whose nursing mothers were fed LID-PTU was in-effective in decreasing the elevated serum TSH in the neonate through day 8 of life, whereas a slight but significant decrease in serum TSH was observed on day 10. Chronic daily TRH-AS administration to neonatal rats through day 10 of life had no effect on the later development of the hypothalamic-pituitary-thyroid axis. These findings suggest that TRH does not participate in TSH regulation during the perinatal life in the rat and that thyroid hormones are probably the main regulators of TSH secretion during this period. Placental TRH is not important in regulating TSH secretion in the fetal rat. Furthermore, TRH "deprivation" during neonatal life does not prevent normal later development of the hypothalamic-pituitary-thyroid axis.