Incidence, and gender, age and ethnic distribution of sarcomas in the republic of suriname from 1980 to 2008.

OBJECTIVE: We report on the incidence and the gender, age, and ethnic distribution of sarcomas diagnosed between 1980 and 2008 in the multi-ethnic Republic of Suriname. METHODS: Total and average yearly number of cases, crude rates, as well as relevant population data were derived from the records of the Pathologic Anatomy Laboratory and the General Bureau of Statistics, respectively, and stratified according to gender, age groups 0-19, 20-49 and 50+ years, and the largest ethnic groups (Hindustani, Creole, Javanese and Maroons). RESULTS: Between 1980 and 2008, 258 sarcomas were diagnosed in Suriname, ie at a frequency of nine per year and an annual rate of two per 100 000. Overall, there was 0.9 male per female, two to four cases per year in each age group, and one to three patients in each ethnic group. Soft-tissue sarcomas comprised approximately 80% of overall cases, with a male/female ratio that was approximately 0.5; almost 90% of patients were older than 20 years; more than one-third was Creole. Leiomyosarcoma, fibrosarcoma and liposarcoma were most frequently encountered (90 cases), particularly above 20 years of age, while leiomyosarcomas seemed, additionally, more common in women and Creoles or Maroons. The most numerous bone tumours were primitive neuroectodermal tumour/Ewing tumour and osteosarcoma (37 cases). They were more common in males, the youngest age group, and Hindustanis and Creoles. CONCLUSIONS: The incidence of sarcomas in Suriname, and their gender, age and ethnic distribution in general, seemed comparable with international data. The main exception might be leiomyosarcoma which might have a predilection for Afro-Surinamese.

Safety and efficacy of percutaneous nephrolithotomy for the treatment of paediatric urolithiasis.

INTRODUCTION: Paediatric percutaneous nephrolithotomy (PCNL) has revolutionised the treatment of paediatric nephrolithiasis. Paediatric PCNL has been performed using both adult and paediatric instruments. Stone clearance rates and complications vary according to the technique used and surgeon experience. We present our experience with PCNL using adult instruments and a 28Fr access tract for large renal calculi in children under 18 years. METHODS: All patients undergoing PCNL at our institution between 2000 and 2009 were reviewed. Demographics, surgical details and post-operative follow-up information were obtained to identify stone clearance rates and complications. RESULTS: PCNL was performed in 32 renal units in 31 patients (mean age: 10.8 years). The mean stone diameter was 19mm (range: 5-40mm). Twenty-six cases required single puncture and six required multiple tracts. Overall, 11 staghorn stones, 10 multiple calyceal stones and 11 single stones were treated. Twenty-seven patients (84%) were completely stone free following initial PCNL. Two cases had extracorporeal shock wave lithotripsy for residual fragments, giving an overall stone free rate of 91% following treatment. There was no significant bleeding or sepsis encountered either during the operation or in the post-operative setting. No patient required or received a blood transfusion. CONCLUSIONS: Paediatric PCNL can be performed safely with minimal morbidity using adult instruments for large stone burden, enabling rapid and complete stone clearance.

Substance use among university students at the St Augustine Campus of The University of the West Indies / Uso de sustancias entre los estudiantes universitarios en el Campus de Saint Augustine de la Universidad de West Indies

OBJECTIVE: Substance use and abuse is a well known public health risk that peaks in persons between 18 and 25 years of age and is prevalent among university students. While this has been repeatedly documented in developed nations, there have been limited studies in the English-speaking Caribbean. This study therefore sought to assess the prevalence of alcohol, tobacco and marijuana use among university students in the English-speaking Caribbean and any associated risk factors. METHODS: The study was designed as a descriptive, cross-sectional study to assess substance use in full-time, undergraduate students of The University of the West Indies (UWI), Trinidad and Tobago, over a six-month period. Questionnaires were distributed and students asked to self-report on their use of alcohol, tobacco and marijuana during the preceding six months. RESULTS: The six-month prevalence rate for alcohol was 70% and 28% of students were identified as regular users. Binge drinking was estimated at 31%. Muslims were least likely to have used alcohol when compared to other religious groupings. The prevalence rate for tobacco and marijuana was 17% and 13%, respectively. Ten per cent used all three substances. The use ofall three substances was associated with multiple problems. CONCLUSION: We conclude that substance use is common among many students of the UWI but generally lower than reports from other regions of the world. Despite this, substance use is associated with a number ofproblems and immediate educational interventions may be necessary to assist students in making informed and responsible choices.

OBJETIVO: El uso y abuso de sustancias es un riesgo bien conocido de la salud pública, que alcanza sus niveles más altos en personas entre los 18 y 25 años de edad, y es prevaleciente entre estudiantes universitarios. Si bien este fenómeno ha sido documentado una y otra vez en países desarrollados, los estudios en el Caribe anglófono han sido limitados. Por lo tanto, este estudio se propuso evaluar la prevalencia del uso del alcohol, el tabaco, y la marihuana, entre los estudiantes universitarios del Caribe angloparlante, y cualquier factor de riesgo asociado. MÉTODOS: El estudio se diseñó como un estudio descriptivo transversal para evaluar el uso de sustancias en estudiantes de pregrado a tiempo completo en la Universidad de West Indies (UWI), Trinidad y Tobago, por un periodo de seis meses. Se distribuyeron encuestas y se les pidió a los estudiantes entregar auto-reportes sobre el uso que habían hecho del alcohol, el tabaco y la marihuana en los seis meses precedentes. RESULTADOS: La tasa de prevalencia de seis meses para el alcohol fue del 70% y 28% de los estudiantes fueron identificados como usuarios regulares. El consumo de alcohol en forma de borracheras deliberadas se estimó en un 31%. Los musulmanes fueron los menos propensos al consumo de alcohol, en comparación con los restantes grupos religiosos. La tasa de prevalência para el tabaco y la marihuana fue de 17% y 13% respectivamente. El diez por ciento hacía uso de las tres sustancias. El uso de las tres sustancias estaba asociado a múltiples problemas. CONCLUSIÓN: Concluimos que el uso de sustancias es común entre muchos estudiantes de UWI, pero de modo general se halla por debajo de lo que se reporta desde otras regiones del mundo. No obstante, el uso de sustancias se encuentra asociado con un número de problemas, y puede que se requieran intervenciones educacionales inmediatas para ayudar a los estudiantes, de modo que estos puedan tomar decisiones responsables e informadas.

One to 2-year surveillance intervals reduce risk of colorectal cancer in families with Lynch syndrome.

BACKGROUND & AIMS: Two percent to 4% of all cases of colorectal cancer (CRC) are associated with Lynch syndrome. Dominant clustering of CRC (non-Lynch syndrome) accounts for 1%-3% of the cases. Because carcinogenesis is accelerated in Lynch syndrome, an intensive colonoscopic surveillance program has been recommended since 1995. The aim of the study was to evaluate the effectiveness of this program. METHODS: The study included 205 Lynch syndrome families with identified mutations in one of the mismatch repair genes (745 mutation carriers). We also analyzed data from non-Lynch syndrome families (46 families, 344 relatives). Patients were observed from January 1, 1995, until January 1, 2009. End points of the study were CRC or date of the last colonoscopy. RESULTS: After a mean follow-up of 7.2 years, 33 patients developed CRC under surveillance. The cumulative risk of CRC was 6% after the 10-year follow-up period. The risk of CRC was higher in carriers older than 40 years and in carriers of MLH1 and MSH2 mutations. After a mean follow-up of 7.0 years, 6 cases of CRC were detected among non-Lynch syndrome families. The risk of CRC was significantly higher among families with Lynch syndrome, compared with those without. CONCLUSIONS: With surveillance intervals of 1-2 years, members of families with Lynch syndrome have a lower risk of developing CRC than with surveillance intervals of 2-3 years. Because of the low risk of CRC in non-Lynch syndrome families, a less intensive surveillance protocol can be recommended.

On-the-fly cross flow laser guided separation of aerosol particles based on size, refractive index and density-theoretical analysis.

Laser separation of particles is achieved using forces resulting from the momentum exchange between particles and photons constituting the laser radiation. Particles can experience different optical forces depending on their size and/or optical properties, such as refractive index. Thus, particles can move at different speeds in the presence of an optical force, leading to spatial separations. In this paper, we present a theoretical analysis on laser separation of non-absorbing aerosol particles moving at speeds (1-10 cm/sec) which are several orders of magnitude greater than typical particle speeds used in previous studies in liquid medium. The calculations are presented for particle deflection by a loosely focused Gaussian 1064 nm laser, which simultaneously holds and deflects particles entrained in flow perpendicular to their direction of travel. The gradient force holds the particles against the viscous drag for a short period of time. The scattering force simultaneously pushes the particles, perpendicular to the flow, during this period. Our calculations show particle deflections of over 2500 µm for 15 µm aerosol particles, and a separation of over 1500 µm between 5 µm and 10 µm particles when the laser is operated at 10 W. We show that a separation of about 421 µm can be achieved between two particles of the same size (10 µm) but having a refractive index difference of 0.1. Density based separations are also possible. Two 10 µm particles with a density difference of 600 kg/m3 can be separated by 193 µm. Examples are shown for separation distances between polystyrene, poly(methylmethacrylate), silica and water particles. These large laser guided deflections represent a novel achievement for optical separation in the gas phase.

Substance use among university students at the St Augustine campus of the University of the West Indies.

OBJECTIVE: Substance use and abuse is a well known public health risk that peaks in persons between 18 and 25 years of age and is prevalent among university students. While this has been repeatedly documented in developed nations, there have been limited studies in the English-speaking Caribbean. This study therefore sought to assess the prevalence of alcohol, tobacco and marijuana use among university students in the English-speaking Caribbean and any associated risk factors. METHODS: The study was designed as a descriptive, cross-sectional study to assess substance use in full-time, undergraduate students of The University of the West Indies (UWI), Trinidad and Tobago, over a six-month period. Questionnaires were distributed and students asked to self-report on their use of alcohol, tobacco and marijuana during the preceding six months. RESULTS: The six-month prevalence rate for alcohol was 70% and 28% of students were identified as regular users. Binge drinking was estimated at 31%. Muslims were least likely to have used alcohol when compared to other religious groupings. The prevalence rate for tobacco and marijuana was 17% and 13%, respectively Ten per cent used all three substances. The use of all three substances was associated with multiple problems. CONCLUSION: We conclude that substance use is common among many students of the UWI but generally lower than reports from other regions of the world. Despite this, substance use is associated with a number of problems and immediate educational interventions may be necessary to assist students in making informed and responsible choices.

Uro-genital bleeding in pre-menarcheal girls: dilemmas of child abuse.

Uro-genital bleeding in pre-menarcheal girls always raises concerns regarding child abuse. There are serious social issues involved; however, before labeling it as sexual abuse, all efforts must be made to rule out an organic pathology. We recently encountered two young girls of Afro-Caribbean origin who presented with vaginal bleeding with concerns from referring physicians about child/sexual abuse. On examination both had a rare condition of urethral prolapse. One of them underwent four-quadrant excision and the other was treated conservatively with urethral catherization.

Pure esophageal atresia with no gap and associated intra-abdominal calcification.

Pure esophageal atresia (PEA) is characterized by a long gap in between the two pouches. Primary anastomosis is usually not feasible and various techniques have been described in the literature to bridge this gap. We describe a case of PEA where there was no gap externally in between the two pouches and associated intra-abdominal calcification.

"Total Gastric Dissociation (TGD)" in difficult clinical situations.

BACKGROUND: Since the first report by Bianchi in 1997, TOGD has been found to be safe and effective in patients with gastro-oesophageal reflux (GOR) with neurological impairment. This paper explores the versatility of total gastric dissociation (TGD) in difficult clinical situations. METHODS: The medical records of 11 neurologically normal children treated with TGD and gastrostomy after failure of conventional procedures between 1999 and 2004 were reviewed with respect to demographic data, initial diagnosis, previous operations, postoperative complications, feeding pattern, and follow-up. RESULTS: There were 7 males and 4 females. The mean age at operation was 52.7 months (24 to 72 m). The indications were severe colo-oesophageal reflux in 3; 1 post-fundoplication necrotic stomach; 1 gastric remnant after subtotal gastrectomy for bleeding; 1 microgastria; 2 with severe oesophageal obstruction following repeated failed repair of congenital stenosis of the oesophagus and after fundoplication; 1 congenital short oesophagus with left-sided congenital diaphragmatic hernia; and 2 with severe dysfunctional oesophagus following repair of congenital tracheo-oesophageal cleft. Full oral or gastrostomy feeding was established by the 5th postoperative day. The average follow-up was 47.2 months (24-72 months). There were 4 late deaths in the group: 2 with respiratory failure, 1 with sepsis secondary to peritonitis (small bowel herniation into the thorax) and 1 with pneumococcal infection. Seven patients are alive and thriving with markedly reduced episodes of chest infections and hospitalizations. CONCLUSIONS: In this study TGD presented with no peri-operative morbidity and mortality and had good long-term results. The procedure offers a safe alternative for neurologically normal children after the failure of conventional surgical procedures.

Efficacy and safety of the first parenteral selective COX-2 inhibitor, parecoxib sodium, in adult patients with postoperative pain.

Parecoxib, a prodrug of valdecoxib, a selective COX-2 inhibitor, has been recently introduced for the treatment of moderate to severe postoperative pain. This prospective, open, multicentric study enrolled 260 patients undergoing orthopaedic, gynaecological, dental and general surgery. Postoperatively, patients were treated with parecoxib, 40 mg IM/IV. There was a statistically significant decrease in the mean pain intensity score (p<0.05). At the end of 24 hours, 89.6% of total cases had a very good to total relief of pain. The mean duration of analgesia was 19.26 hours and mean time of onset of analgesia was 16.25 minutes ranging from 11-20 minutes. The laboratory values were within normal limits. The drug was well tolerated. There was no report of any hypersensitivity reaction. This study suggests that parecoxib, in a dose of 40 mg IM/IV, is an effective and safe option for the management of postoperative pain.

Epigastric heteropagus twins--a report of four cases.

Asymmetrical conjoined twinning is an extremely rare congenital anomaly constituting only 1%-2% of all conjoined twins. In epigastric heteropagus twins (EHT), the dependent portion (parasite) is smaller than the host (autosite). The embryopathy is related to incomplete cleavage of the embryo at 2 weeks of gestation. However, some form of ischaemic insult in early gestation leads to selective atrophy of the cranial part of one of the monozygous twins. We report our experience with four cases of EHT and a review of the literature with a discussion of possible embryopathy.

Incarcerated diaphragmatic hernia secondary to plication for eventration of diaphragm.

Diaphragmatic plication is the procedure of choice for congenital diaphragmatic eventration. In the absence of complications, most newborns with eventration do well after plication and have normal long-term respiratory functions. However complications are rare. Recurrence, ipsilateral pneumothorax and rupture of the diaphragm have been reported in literature. We report a case of incarcerated diaphragmatic hernia in a two-year-old child who had undergone plication for eventration of the diaphragm at six months of age.

Synapse formation is arrested in retinal photoreceptors of the zebrafish nrc mutant.

We describe the effects of a recessive mutation on visual behavior, the electroretinogram (ERG), and photoreceptor structure in zebrafish. At 6 d post-fertilization (dpf), no optokinetic reflex could be elicited in no optokinetic response c (nrc) mutant animals under any test condition. The animals exhibited ERG responses at 5-7 dpf that were markedly abnormal and could be categorized into two groups. The first showed an initial negative a-wave followed by a delayed positive b-wave of small amplitude. Often a second ERG-like response was recorded after the initial b-wave. The second group showed only a large negative a-wave; an initial b-wave was not evident. In most recordings additional oscillatory waves varying in number, amplitude, and time course were observed. Multiple responses at the cessation of long-duration flashes were also observed. Light and electron microscopy revealed that the cone photoreceptor pedicles of nrc fish were highly abnormal. Although the appropriate number of synaptic ribbons formed in these terminals, they "floated" in the terminal, unassociated with postsynaptic processes or arciform densities. The few processes invaginating the nrc pedicles resembled those of horizontal cells. Invaginating bipolar cell processes were rare, but basal contacts were observed on pedicle surfaces. The severity of the mutation did not change between 6 and 8 dpf, showing that there is neither a delay in development nor a degeneration of the terminals; rather, nrc pedicle development appears arrested. Bipolar cell terminals in the inner plexiform layer made normal ribbon synapses; thus, the mutation appears to affect only the outer retina.

Neonatal Hirschsprung's disease.

Since the classic description of this disease by Harold Hirschsprung's. In 1886 just over a century ago, there has been a marked evolution in the diagnostic modalities, understanding of the pathophysiology, unraveling of genetic association and the treatment approach of this disease. Recent research on the molecular biology of the disease has bestowed us with a clearer understanding of the pathogenesis of the disease. Genetic deletions have been identified which explain the familial incidence of 3.6%-7.8%, and in some kindreds the inheritance rate approaches 50%. Improvement in the diagnostic approaches has evolved from full thickness rectal biopsy (under GA) to suction rectal biopsy. The development of the histochemical staining for acetylcholinesterase, allows rapid identification in the lamina propria of hypertrophied extrinsic nerve fibers which have proliferated in the absence of intrinsic ganglion cells. Frozen sections now permit screening for normal ganglia in the myenteric plexus from seromuscular biopsies during the definitive pull-through procedures or leveling colostomy. This service, however, requires significant infrastructure and an expert pathologist, not widely available. Hirschsprung's disease (HD) variants like intestinal neuronal dysplasia(IND), hypoganglionosis are better identified and treated with availability of histochemical staining. The three-stage procedure till date remains the gold standard; however, increasingly, the world over, two stage and even single stage procedures are being tried. In the era of minimally invasive surgery, perineal pull through procedure has been attempted with or without laparoscopic assistance.

Tuning of photoreceptor spectral sensitivity in fireflies (Coleoptera: Lampyridae).

Sexual communication between male and female fireflies involves the visual detection of species-specific bioluminescent signals. Firefly species vary spectrally in both their emitted light and in the sensitivity of the eye, depending on the time when each is active. Tuning of spectral sensitivity in three firefly species that occupy different photic niches was investigated using light and electron microscopy, microspectrophotometry, and intracellular recording to characterize the location and spectral absorption of the screening pigments that filter incoming light, the visual pigments that receive this filtered light, and the visual spectral sensitivity. Twilight-active species had similar pink screening pigments, but the visual pigment of Photinus pyralis peaked near 545 nm, while that of P. scintillans had a lambdamax near 557 nm. The night-active Photuris versicolo, had a yellow screening pigment that was uniquely localized, while its visual pigment was similar to that of P. pyralis. These results show that both screening and visual pigments vary among species. Modeling of spectral tuning indicates that the combination of screening and visual pigments found in the retina of each species provides the best possible match of sensitivity to bioluminescent emission. This combination also produced model sensitivity spectra that closely resemble sensitivities measured either with electroretinographic or intracellular techniques. Vision in both species of Photinus appears to be evolutionarily tuned for maximum discrimination of conspecific signals from spectrally broader backgrounds. Ph. versicolor, on the other hand, appears to have a visual system that offers a compromise between maximum sensitivity to, and maximum discrimination of, their signals.

A case of Fournier gangrene complicating idiopathic nephrotic syndrome of childhood.

A 10-year-old boy presenting with steroid resistant nephrotic syndrome developed Fournier gangrene of the scrotum. Antimicrobial drug therapy, intravenous albumin, excision of necrotic scrotum and left orchidectomy followed by skin grafting 3 weeks later led to an excellent cosmetic and medical result. Six months later he remains nephrotic on diuretic and angiotensin converting enzyme inhibitor medication.

Total colonic aganglionosis: diagnosis and management in a 12-year-old boy.

Total colonic aganglionosis (TCA) is an unusual form of Hirschsprung's disease, and most of these present within the first few weeks and nearly all by the end of the first year of life. Very few cases presenting in older childhood or adulthood have been reported. Without a high index of suspicion these cases can easily be missed and, therefore, patients undergo repeated laparotomies for subacute intestinal obstruction without relief of symptoms. The diagnosis is suspected on operative findings and confirmed by histological evaluation of seromuscular biopsy specimens. Proper diagnosis will prevent loss of bowel length caused by inadvertent resection and will help in performing an optimal procedure to treat these patients. Discussed herein is another case of TCA in a 12-year-old boy with review of relevant literature.

Surgical aspects of chronic constipation in children.

Chronic constipation accounts for 3% of paediatric visits. These patients can be broadly classified into three groups: (a) medical group (60-70%), (b) surgical group (20-25%), (c) refractory constipation group (5-10%). The first two groups can be managed by dietary adjustments and surgery respectively. The recognition and management of refractory constipation is a slower process and needs close scrutiny and perseverance before a definite therapeutic option could be decided.

Neurogenic bladder: urodynamic and surgical aspects.

Children with spina bifida often have vesico-urethral dysfunction manifesting either as upper urinary tract deterioration or voiding dysfunction, chiefly incontinence. Surgery of the back and presence of or increase in hydrocephalus may contribute to neuro-urologic worsening; secondary cord tethering and syrinx or hydromyelia may be additional factors coming into play later in life. Urodynamic assessment using simple modalities like uroflowmetry, external sphincter EMG, residual urine volume and cystometry provide data useful to classify patients according to detrusor and sphincter activity. Besides diagnosis, urodynamic studies are useful in guiding therapy of children with vesico-urethral dysfunction, and for their follow-up to detect sub-clinical deterioration. They also help to prognosticate risk of upper tract deterioration and the possible success of measures to contain incontinence. Urodynamic data in thirty one patients with spinal dysraphism who presented to us with urologic symptoms were analysed. Twenty-three children had hyper-reflexic bladders while in the other 8 the bladder was areflexic. 13 children showed upper tract dilatation. The leak point volume was significantly lower in this group of patients compared to those who did not show upper tract dilatation. Our results are comparable to earlier similar studies.