Persistent left superior vena cava: An anatomical variation.

The persistent left superior vena cava (LSVC) is a common anomaly of congenital heart disease. The presence of LSVC is commonly associated with other congenital cardiac anomalies such as atrial septal defect, tetralogy of fallot, aortic coarctation, ventricular septal defect and very rarely it occurs as an isolated finding. During a routine dissection for undergraduate students, a persistent LSVC along with variation in anterior cardiac vein and right septal pouch (RSP) was observed in heart of an approximately 48-year-old male cadaver. The persistent LSVC was draining into the right atrium via coronary sinus. The persistent LSVC is usually insignificant haemodynamically as commonly it drains into right atrium via coronary sinus, but incidental finding of LSVC is important to surgeons, interventional nephrologists and radiologists before placement of central venous access device. The insertion of central venous catheter via left internal jugular vein is difficult in presence of persistent LSVC. The right superior vena cava was normal. An anterior cardiac vein joined with the right marginal vein to form a common vein. The common vein opened into the right atrium. We also observed a RSP attached to the limbus fossa ovalis inferiorly which is a kangaroo pouch-like structure. A septal pouch is potential site predispose to thrombus formation and is more common on left side. In this case report we discuss embryology, clinical significance and review of literature related to persistent LSVC, anterior cardiac vein and SP.

Standardization of the technique of silicon injection of human cadaveric heads for opacification of cerebral vasculature in Indian conditions.

A surgeon's understanding of the surgical anatomy can be greatly enhanced by the dissection of preserved cadaveric specimens. A reliable and inexpensive biological model for testing and standardization of dye injection concentrations is proposed utilizing the goat's head as a biological model. The first phase was concerned with standardization of the dye by titrating its concentration and injecting various amounts into cerebral vessels of a goat's head until an optimal concentration had been ascertained. In the second phase, this optimum concentration of the dye was injected into four human cadaveric heads following the same technique standardized using the goat's head. Upon dissecting the four cadaveric human heads which were injected with silicon dyes and preserved in 10% formalin, the vessels were all well-opacified and the brain was of near normal consistency and good for dissection, without showing any features of putrefaction. The goat model, having similar color, texture, and the handling as the cadaveric head, offers an opportunity to test indigenously manufactured polymerizing dyes in the future. This biological model, therefore, has the potential to considerably reduce the cost of cadaver preparation.

Identification of groupers based on pyloric caeca differentiation.

The examination of nine species of groupers present in south-east Indian waters has indicated that the pyloric caeca number, pattern and colouration are reliable and useful characters for identification. Three distinct morphotypes of pyloric caeca were observed in this study.

Morphological and morphometrical maturation of ventral cochlear nucleus in human foetus.

Auditory impulses perceived by the hair cells of the organ of corti are relayed in the cochlear nucleus, the first relay station in the brainstem, by the cochlear nerve. The human foetus is well known to respond to sound during the last trimester of gestation. On the contrary, studies conducted in rat, cat and mouse have shown that these mammals have an immature auditory system at the time of birth. There are very few reports available regarding the morphological and functional maturation of the cochlear nucleus in human. Although the human cochlear nucleus neurons attain adult morphological characters by mid-gestation, there are hardly any studies discussing the functional maturation of the cochlear nucleus. Hence the present study was aimed at observing the morphological as well as functional maturation of the human foetal cochlear nuclei at various gestational ages. Morphological maturation was observed qualitatively while stereological estimation of the volume of well defined ventral cochlear nucleus (VCN) was calculated by the Cavalieri principle; neuronal count and density was estimated by dissector principle. The functional maturation was assessed by observing the expression of synaptophysin, a synaptic marker, at different gestational ages and by the presence of parvalbumin, a calcium binding functional neuronal marker by immunohistochemistry. Neurons showed coarse Nissl's substance and well developed cell processes and gradual increase in cell size by the 24th-30th gestational week. Synaptophysin labeling in the complete cochlear nucleus was observed at 20 weeks of gestation. Adult pattern of synaptophysin labeling was observed finally at37weeks of gestation. Earliest presence of parvalbumin expression was detected at 16 weeks of gestation and a distinct adult pattern was seen at 37 weeks of gestation. This study concluded that morphological and functional maturation of the human cochlear nuclei occurs simultaneously during mid-gestation which represents the critical period of development and continues up to term.

Chronic co-administration of nalbuphine attenuates the development of opioid dependence.

Nalbuphine is an agonist of κ-opioid receptors and a partial agonist of µ-opioid receptors, which can stimulate κ-receptors and antagonize the acute rewarding effects of morphine. It is widely used either as an analgesic or as an adjuvant with morphine. This present study aimed to compare the acute and chronic effects of nalbuphine on the naloxone-precipitated opiate-withdrawal in rats. Male adult Wistar albino rats (150-175 g, n = 160) were made physically dependent by administrating increasing dose of morphine (5-25 mg/kg; i.p.). Motor activity was measured for 25 min at five-minute intervals on days 0, 1, 3, 5, and 6 using Activity Monitor (Coulbourn Instruments, Inc. USA) and True-scan software. The withdrawal was precipitated with intraperitoneal injections of naloxone (1 mg/kg) 4 h after the last injection of morphine. Somatic signs of withdrawal were scored using the global Gellert-Holtzman rating scale. Nalbuphine was co-administered acutely and chronically at various doses (0.1, 0.3, 1.0, and 3.0 mg/kg; i.p.) with morphine. In general, the opiate-dependent rats showed a significant increase in motor activity and Gellert-Holtzman score. Animals co-administered with chronic doses of nalbuphine showed a significant decrease in motor activity and naloxone-precipitated opiate withdrawal, but acute nalbuphine treatment did not attenuate the development of opioid dependence. These findings suggest that nalbuphine could be used as an effective pharmacological adjunct in the treatment of opioid addiction.

Fluoride-associated ultrastructural changes and apoptosis in human renal tubule: a pilot study.

The susceptibility of the kidneys to fluoride toxicity can largely be attributed to its anatomy and function. As the filtrate moves along the complex tubular structure of each nephron, it is concentrated in the proximal and distal tubules and collecting duct. It has been frequently observed that the children suffering from renal impairments also have some symptoms of dental and skeletal fluorosis. The findings suggest that fluoride somehow interferes with renal anatomy and physiology, which may lead to renal pathogenesis. The aim of this study was to evaluate the fluoride-associated nephrotoxicity. A total of 156 patients with childhood nephrotic syndrome were screened and it was observed that 32 of them had significantly high levels ( p ≤ 0.05) of fluoride in urine (4.01 ± 1.83 ppm) and serum (0.1 ± 0.013 ppm). On the basis of urinary fluoride concentration, patients were divided into two groups, namely group 1 (G-1) ( n = 32) containing normal urine fluoride (0.61 ± 0.17 ppm) and group 2 (G-2) ( n = 32) having high urine fluoride concentration (4.01 ± 1.83 ppm). Age-matched healthy subjects ( n = 33) having normal levels of urinary fluoride (0.56 ± 0.15 ppm) were included in the study as control (group 0 (G-0)). Kidney biopsies were taken from G-1 and G-2 only, who were subjected to ultrastructural (transmission electron microscopy) and apoptotic (terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling) analysis. Various subcellular ultrastructural changes including nuclear disintegration, chromosome condensation, cytoplasmic ground substance lysis, and endoplasmic reticulum blebbing were observed. Increased levels of apoptosis were observed in high fluoride group (G-2) compared to normal fluoride group (G-1). Various degrees of fluoride-associated damages to the architecture of tubular epithelia, such as cell swelling and lysis, cytoplasmic vacuolation, nuclear condensation, apoptosis, and necrosis, were observed.

Comparison of unbiased stereological estimation of total number of cresyl violet stained neurons and parvalbumin positive neurons in the adult human spiral ganglion.

Estimation of total number of neurons in the spiral ganglion (SG) at various ages and their functional status is important as these neurons are constantly exposed to noise and other environmental factors that may lead to neuronal loss with aging due to excitotoxic damage. Parvalbumin (PV) is a calcium-binding protein (CBP), found in highly metabolically active neurons. It helps in buffering cytosolic calcium, which is essential for neurotransmitter release. The neurons in the adult human SG express PV more strongly than other CBPs like calbindin and calretinin. These CBPs can be used as signatures to recognise neurons. In the present study, we quantified the number of neurons expressing PV by unbiased stereology and compared it to the number of neurons stained by cresyl violet (CV), which is a Nissl stain, in the adult human SG. Five adult human cadaveric temporal bones were obtained from the forensic science mortuary, after due clearance from the institute ethics committee. Independent CV stained and PV immunostained sections were used to estimate the total number of neurons (optical fractionator), with StereoInvestigator (SI) software. The estimated total number of SG neurons was 27,485±3251 and 26,705±1823 in the PV and CV stained sections, respectively. There was no significant difference between the estimates (p=0.552). Therefore, CV staining is simpler and more cost effective when estimating neuronal number. Although PV stains spiral ganglion neurons (SGNs) with a greater intensity and provides a functional status, its tedious protocol limits its use for quantification.

An Evaluation of the Surgical Trauma to Intracochlear Structures After Insertion of Cochlear Implant Electrode Arrays: A Comparison by Round Window and Antero-Inferior Cochleostomy Techniques.

To evaluate the extent of intracochlear damage by histologic assessment of cadaveric temporal bones after insertion of cochlear implants by: round window approach and cochleostomy approach. Cochlear implantation was performed by transmastoid facial recess approach in 10 human cadaveric temporal bones. In 5 temporal bones, electrode insertion was acheieved by round window approach and in the remaining 5 bones, by cochleostomy approach. The bones were fixed, decalcified, sectioned and studied histologically. Grading of insertion trauma was assessed. In the round window insertion group, 2 bones had to be excluded from the study: one was damaged during handling with electrode extrusion and another bone did not show any demonstrable identifiable cochlear structure. Out of the 3 temporal bones, a total of 35 sections were examined: 24 demonstrated normal cochlea, 4 had basilar membrane bulging and 7 had fracture of bony spiral lamina. In the cochleostomy group, histology of 2 bones had to be discarded due to lack of any identifiable inner ear structures. Out of the 3 bones studied, 18 sections were examined: only 3 were normal, 4 sections had some bulge in spiral lamina and 11 had fracture of bony spiral lamina. The fracture of spiral lamina and bulge of basement membrane proportion is relatively higher if we perform cochleostomy as compared to round window approach. Therefore, round window insertion is relatively less traumatic as compared to cochleostomy. However, our sample size was very small and a study with a larger sample is required to further validate these findings.

Growth and refinement of excitatory synapses in the human auditory cortex.

We had earlier demonstrated a neurofilament-rich plexus of axons in the presumptive human auditory cortex during fetal development which became adult-like during infancy. To elucidate the origin of these axons, we studied the expression of the vesicular glutamate transporters (VGLUT) 1 and 2 in the human auditory cortex at different stages of development. While VGLUT-1 expression predominates in intrinsic and cortico-cortical synapses, VGLUT-2 expression predominates in thalamocortical synapses. Levels of VGLUT-2 mRNA were higher in the auditory cortex before birth compared to postnatal development. In contrast, levels of VGLUT-1 mRNA were low before birth and increased during postnatal development to peak during childhood and then began to decrease in adolescence. Both VGLUT-1 and VGLUT-2 proteins were present in the human auditory cortex as early as 15GW. Further, immunohistochemistry revealed that the supra- and infragranular layers were more immunoreactive for VGLUT-1 compared to that in Layer IV at 34GW and this pattern was maintained until adulthood. As for VGLUT-1 mRNA, VGLUT-1 synapses increased in density between prenatal development and childhood in the human auditory cortex after which they appeared to undergo attrition or pruning. The adult pattern of VGLUT-2 immunoreactivity (a dense band of VGLUT-2-positive terminals in Layer IV) also began to appear in the presumptive Heschl's gyrus at 34GW. The density of VGLUT-2-positive puncta in Layer IV increased between prenatal development and adolescence, followed by a decrease in adulthood, suggesting that thalamic axons which innervate the human auditory cortex undergo pruning comparatively late in development.

Preoperative chemotherapy and radiotherapy for esophageal carcinoma.

From October 1986 to January 1991, 47 patients with esophageal cancer (29 squamous, 18 adenocarcinoma) were treated with simultaneous radiotherapy (3000 or 3600 cGy) and chemotherapy (infusional 5-fluorouracil, cisplatin) delivered during a 5-week period. This treatment was well tolerated; 44 patients (94%) completed a full course of therapy, 40 (85%) had relief from dysphagia, and 21 (45%) noted either weight gain or no net weight loss. One patient (2%) died of complications (tracheoesophageal fistula, perforated ulcer) during chemotherapy and radiotherapy. The remaining 46 patients were referred for operation. Six refused because of excellent relief of their dysphagia, and one was denied operation. Thirty-nine patients went to operation, and 34 (83%) had lesions that were resectable. Eight of the 39 surgically treated patients (21%) had no evidence of residual tumor identified in the resected specimens. One of these complete responders died 7 weeks postoperatively after multiple complications (3% operative mortality rate). Three of the remaining seven have also died since the operation, one of recurrent cancer and two with no known recurrent disease. Actuarial survival in this present series was significantly better than that of our 1980 to 1985 historical control patients (p less than 0.005). There was no difference between patients with squamous carcinoma and those with adenocarcinoma with regard to the prevalence of complete response or long-term survival. Survival of the seven patients who did not undergo operation was comparable with that of the 34 patients in whom esophagectomy was performed. This study suggests that combined preoperative chemotherapy plus radiotherapy for esophageal cancer is well tolerated, provides excellent palliation of symptoms, allows for a high rate of resectability, is equally effective for squamous carcinoma and adenocarcinoma, and provides encouraging early results with regard to long-term survival. The data also call into question the role of esophagectomy, particularly in patients who have a complete response to preoperative therapy.

Multimodality therapy for adenocarcinoma of the esophagus.

Few reports exist detailing results of multimodality treatment for adenocarcinoma of the esophagus. We have treated 28 such patients using a preoperative regimen consisting of two courses of cisplatin and 5-fluorouracil with radiation (either 3,000 or 3,600 cGy). There were 25 men and 3 women (mean age, 62.9 years; range, 35 to 86 years), and 16 patients were known to have Barrett's esophagus. Dysphagia was present for a mean of 2.7 months, and the average weight loss was 6.5 kg. Tumors ranged from 2 to 10 cm in length (mean, 5.2 +/- 1.8 cm) with American Joint Committee on Cancer clinical stage I in 2 patients, stage II in 19 patients, and stage III in 7. Dysphagia improved in 23 patients (82%), and in 8 (29%) no tumor was detected during radiologic and endoscopic staging after neoadjuvant therapy. Four patients refused operation. Esophagectomy via standard Ivor Lewis approach was accomplished in 20 of 24 patients (87%) undergoing operation. There were no operative deaths, and mean hospital stay was 15.5 +/- 11.6 days. Four patients (17%) were complete responders with no tumor in the resected specimen. Actuarial survival in the 28 patients at 1, 2, and 3 years is 71%, 28%, and 20% respectively. Of the 20 esophagectomy patients, 6 are alive with no evidence of disease at 10, 50, 54, 70, 77, and 84 months. Three of these were complete responders. Only 1 of the 8 patients no undergoing resection is alive at 16 months with no evidence of disease after further radiotherapy and chemotherapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Estimated spectrum of a 4-MV therapeutic beam.

We have made a comparative investigation of the estimated spectra obtained by the Laplace transform analysis of the transmitted exposure data measured in an absorption study of a 4-MV x-ray beam. Four transform pair models currently used with this method have been evaluated. It has been determined that the Archer-Wagner model provides a valid representation of the measured transmission data and yields an estimated spectrum which most closely resembles a Monte Carlo spectrum calculated for a 4-MV therapeutic x-ray beam available from a typical medical accelerator.

Effects of prenatal nicotine exposure on the morphogenesis of somatosensory cortex.

Human reports as well as animal studies have recorded accelerated motor activity, learning, and memory deficits in offsprings of mothers exposed to nicotine during pregnancy. Morphological correlation of these neurobehavioural defects has not been done to date. Here, the cerebral cortex has been evaluated after prenatal nicotine exposure. Groups of pregnant rats were injected IP with nicotine at 2.5 mg/kg/day dosage from gestational day (GD) 6 to term. Morphology of the somatosensory cortex was analysed and compared with that of the control group up to postnatal day (PND) 40. A significant reduction in body weight and brain weight on PND 10 and 20, respectively was observed in nicotine exposed group as compared to age matched controls. Morphometric analysis of the somatosensory cortex showed a reduction in cortical thickness up to PND 20 and decreased cell size at PND 10, 20, and 40 in nicotine-exposed brains. Neuronal density of Layer 5 of somatosensory cortex was greater at PND 20 and 40 in the experimental group. Golgi staining of large pyramidal neurons of Layer 5 showed significantly decreased dendritic branching and increased dendritic spine density in the experimental group at all ages studied. Irregular arrangement of cisternae of rough endoplasmic reticulum, paucity of free ribosomes, and frequent cytoplasmic vacuoles were noted by electron microscopy in many neurons up to PND 40. A large number of electron dense cells were observed in nicotine exposed brains at all the time intervals studied. The morphological features of somatosensory cortex observed after prenatal nicotine administration suggest that the drug delays neuronal maturation and affects intracytoplasmic membrane systems.

Effects of gestational nicotine exposure on hippocampal morphology.

Morphology of the dentate gyrus and Ammon's horn of the hippocampus was observed postnatally in Wistar rats exposed to prenatal nicotine. Pregnant Wistar rats were injected with nicotine (2.5 mg/kg/ day) from gestational day (GD) 6 to term and pups were delivered at term normally. The brains of nicotine-exposed pups at postnatal day (PND) 40 were dissected and processed for araldite embedding. Semithin (0.5 microm) toluidine blue-stained sections of the dentate gyrus, CA3, and CA1 regions of the hippocampus were studied for morphological details. Morphometric analysis showed a significant reduction in the neuronal area of nicotine-exposed brains in all three regions studied. Distal dendritic arbor was significantly less and spine density was more in the granule cells, terminal and basal dendrites of the pyramidal neurons of CA3 and CA1 regions of the hippocampus in the experimental group. CA3 pyramidal neurons showed significantly less apical dendritic thorny excrescence after gestational nicotine exposure. Ultrastructurally the granule cells and the pyramidal neurons of the CA3 and CA1 regions showed increase in free ribosomes and dilatation of rough endoplasmic reticulum (RER) and Golgi apparatus cisternae in the nicotine-treated group. The morphological changes in the hippocampus following prenatal nicotine exposure, as observed in the present study, may contribute to the behavioural abnormalities.

Anomalous cutaneous branch of median nerve in arm: a report of anatomical variation with clinical implications.

The objective of the study was to observe and document the variation on the subject of branches of the median nerve. This report will assist clinicians and surgeons by considering anatomical variation associated with the median nerve in interpreting atypical clinical presentations. The arm and forearm region of a 55 year embalmed male cadaver during educational gross anatomy dissection. We found that an anomalous cutaneous branch arising from the median nerve in the right arm which was passing deep to the tendon of the biceps brachii. Later it enters the cubital fossa and then it is accompanied by the superficial vein of the forearm. The other limb of the cadaver did not show any such variation. No other neural, arterial or muscular variation was observed in either of the limbs. A rare anatomical variation in which the anomalous cutaneous branch arising from the median nerve in the right arm which is later accompanied by a superficial vein in the forearm. Such knowledge is advantageous in nerve grafting and neurophysiological evaluation for diagnosing peripheral neuropathies.

Effect of prenatal loud music and noise on total number of neurons and glia, neuronal nuclear area and volume of chick brainstem auditory nuclei, field L and hippocampus: a stereological investigation.

The present study explores whether prenatal patterned and unpatterned sound of high sound pressure level (110 dB) has any differential effect on the morphology of brainstem auditory nuclei, field L (auditory cortex analog) and hippocampus in chicks (Gallus domesticus). The total number of neurons and glia, mean neuronal nuclear area and total volume of the brainstem auditory nuclei, field L and hippocampus of post-hatch day 1 chicks were determined in serial, cresyl violet-stained sections, using stereology software. All regions studied showed a significantly increased total volume with increase in total neuron number and mean neuronal nuclear area in the patterned music stimulated group as compared to control. Contrastingly the unpatterned noise stimulated group showed an attenuated volume with reduction in the total neuron number. The mean neuronal nuclear area was significantly reduced in the auditory nuclei and hippocampus but increased in the field L. Glial cell number was significantly increased in both experimental groups, being highest in the noise group. The brainstem auditory nuclei and field L showed an increase in glia to neuron ratio in the experimental groups as compared to control. In the hippocampus the ratio remained unaltered between control and music groups, but was higher in the noise group. It is thus evident that though the sound pressure level in both experimental groups was the same there were differential changes in the morphological parameters of the brain regions studied, indicating that the characteristics of the sound had a role in mediating these effects.

Ectopic supernumerary tooth on the inferior nasal concha.

Variations regarding the location of an ectopic tooth in the human nasal cavity, although rare, are documented in the literature, but presence of an ectopic tooth on the inferior nasal concha (INC) has not been reported. We observed an anomalous tooth projecting from the posterior margin of the right INC in two adult female skulls. A small quadrangular tooth projected beyond the posterior margin of the hard palate in one of the skulls and a medium sized conical tooth was observed in the other skull. The affected INC in both skulls were located more inferiorly compared to the opposite side and were in close approximation with the hard palate. No similar findings were noted on the contralateral side nor were there any associated congenital or iatrogenic deformity. The phylogenetic, ontogenetic, and clinical importance of this variant is described. Knowledge of such an anomaly is of paramount importance to otorhinolaryngologists, reconstructive and dental surgeons, and radiologists for identification of such rarities encountered during invasive or non-invasive procedures.