Correction to: Hypoparathyroidism After Total Thyroidectomy: Importance of the Intraoperative Management of the Parathyroid Glands.

In the original version of the article, the last three column headings in Table 3 were mislabeled. The original article has been corrected. Following is the corrected table.

Hypoparathyroidism After Total Thyroidectomy: Importance of the Intraoperative Management of the Parathyroid Glands.

BACKGROUND: Total thyroidectomy is the most common surgical procedure for the treatment of thyroid diseases. Postoperative hypocalcemia/hypoparathyroidism is the most frequent complication after total thyroidectomy. The aim of this study was to evaluate the rate of postoperative hypocalcemia and permanent hypoparathyroidism after total thyroidectomy in order to identify potential risk factors and to evaluate the impact of parathyroid autotransplantation. PATIENTS AND METHODS: We performed a retrospective analysis of 1018 patients who underwent total thyroidectomy at our institution between 2000 and 2016. Medical records were reviewed to analyze patient features, clinical presentation, management and postoperative complications. Descriptive and inferential statistics were employed based on the natural scaling of each included variable. Statistical significance was set at p ≤ 0.05. RESULTS: Mean ± SD age was 46.79 ± 15.9 years; 112 (11.7%) were males and 844 (88.3%) females. A total of 642 (67.2%) patients underwent surgery for malignant disease. The rate of postoperative hypocalcemia, transient, protracted and permanent hypoparathyroidism was 32.8%, 14.43%, 18.4% and 3.9%, respectively. Permanent hypoparathyroidism was significantly associated with the number of parathyroid glands remaining in situ (4 glands: 2.5%, 3 glands: 3.8%, 1-2 glands: 13.3%; p ˂ 0.0001) [OR for 1-2 glands in situ = 5.32, CI 95% 2.61-10.82]. Other risk factors related to permanent hypoparathyroidism were obesity (OR 3.56, CI 95% 1.79-7.07), concomitant level VI lymph node dissection (OR 3.04, CI 95% 1.46-6.37) and incidental parathyroidectomy without autotransplantation (OR 3.6, CI 95% 1.85-7.02). CONCLUSIONS: Identification and in situ preservation of at least three parathyroid glands were associated with a lower rate of postoperative hypocalcemia (30.4%) and permanent postoperative hypoparathyroidism (2.79%).

Medical Utilisation at a Major Sporting Event ­ a descriptive & epidemiological analysis

Background: Medical utilisation and contacts at amateur/international sporting events is an accepted phenomenon, as evidenced by mandatory medical coverage requirements for major events. There is little data however, on the volume and type of contacts expected outside of elite sport. This may lead to inefficient resource allocation and pose challenges to organisers in planning and delivery of medical services. In addition, data on contacts may assist in targeted preventative strategies. Objectives: We aimed to measure resource utilisation at the largest international aquatic sporting event in the hemisphere. We also aimed to measure epidemiological data including the type, location, sporting discipline and outcomes of medical contacts during the event. Methods: This was a prospective observational study conducted under the auspices of the organising committee of the XXX Confederation Centroamericana y del Caribe de Natacion (CCCAN) championships held in Trinidad & Tobago. Anonymised data was collected from event medical contact records, screening and voluntarily reported contacts by team medical staff (for individuals who did not visit event medical staff). We excluded contacts by spectators. Data was collected over a 12 day competition period. Descriptive analysis was undertaken using Microsoft Excel. Injury incidence rate (IR; number of injuries per 1000 athlete-days) and injury incidence proportion (IP; injuries per 100 athletes) were calculated. Results: There was a total of 5037 athlete/official days. There were 110 medical contacts for the event, with 80 occurring in athletes (72.7%). A significant number of non-sport related contacts was observed (60% of total) with a high number of complaints related to exhaustion and inadequate hydration. This was independent of country of origin. Acute gastroenteritis, ear and sinus infections were within expected frequencies. No EMS usage was necessary, and hospital transfers were for diagnostics in all cases. Open water swimming was associated with the most contacts, followed by water polo and swimming. Two-thirds of hospital transfers were for water polo associated injury. There were a total of 54 sport related contacts in 3956 athlete days (IR 13.65 injuries per 1000 athlete-days with an injury incidence proportion, IP; of 6.5 per 100 athletes). Conclusions: Planning for aquatic events must take into consideration non-sport as well as competition related complaints. This study gives important information on medical utilisation for future event planning.

Does pre-existing medical conditions and pre-competition screening identify athletes at risk of medical intervention in competitive Open Water swimming?

Background: Open water swimming is one of the fastest growing mass participation sports worldwide. Analysis of triathlon deaths and cardiac arrests have shown that 75% of these occur in the swimming leg. Less than half had autopsy evidence of cardiac disease, and swimming ability or medical conditions do not appear responsible. Mandatory pre-competition clinical screening has been traditionally promoted in open water swimming to identify athletes at risk of illness or death during competition. The variable nature of this screening however, may not be useful in identifying at risk individuals. Objectives: We aimed to determine whether the presence of pre-existing medical conditions or abnormalities discovered on clinical screening [blood pressure (BP), heart rate (HR), auscultation of heart and lungs and apical palpation] predicted either failure to complete the race or the need for medical contact. Methods: We collected screening and competition data from participants in the two largest regional Open Water competitions in 2017 ­ including international (CCCAN) and mixed ability (ASATT Maracas) athletes. Anonymised data on event medical contacts, failure to finish and screening were analysed, with descriptive results and risk ratios calculated using MedCalc statistical software. Age adjusted values for BP and HR outside the 90th centile was considered abnormal. Results: Overall, 410 athletes participated for which data was available for 400 (mean age 17.9 years, range 7-79; 58% male). There were 30 medical contacts, of which 22 were unable to complete the race. There was no significant sex difference in those unable to complete. The majority of contacts was for the 10k race (60%) with the 5k (23%) the next most common. The most common reason for non-completion was exhaustion. Three scratched due to illness on competition day. 21 athletes were asthmatic, and 2 had cardiac murmurs, however all completed their respective races and none required any medical contact. Asthma (RR 0.3, p=0.39), abnormal physiological measurements (RR 1.32, p=0.84) and other medical conditions (RR 0.94, p=0.96) did not appear predictive. Current illness was the only significant predictor of failure to complete or medical contact. (RR 6.67; 95% CI 2.36 -18.84), however a larger sample may be necessary to show significance. Conclusions: There is much variability in pre-competition screening for Open Water swimming, as with other sports. Intuitively, only current illness predicts failure to complete/medical contact, although it is unclear whether this can be used as a surrogate for athletes at risk of more serious sequelae. Pre-existing medical conditions such as asthma do not appear to be contributory to non-completion, nor does moderately abnormal physiological measurements. Given that cardiac arrythmias or structural abnormalities are implicated in some deaths during open water swimming, adding resting electrocardiography and possible echocardiography to pre-participation medical examination may be reasonable, however the effectiveness of this strategy is disputed. There appears to be little benefit in clinical screening immediately prior to competition, with a more thorough, structured pre-training examination likely to be superior.

An accurate and efficient bayesian method for automatic segmentation of brain MRI.

Automatic three-dimensional (3-D) segmentation of the brain from magnetic resonance (MR) scans is a challenging problem that has received an enormous amount of attention lately. Of the techniques reported in the literature, very few are fully automatic. In this paper, we present an efficient and accurate, fully automatic 3-D segmentation procedure for brain MR scans. It has several salient features; namely, the following. 1) Instead of a single multiplicative bias field that affects all tissue intensities, separate parametric smooth models are used for the intensity of each class. 2) A brain atlas is used in conjunction with a robust registration procedure to find a nonrigid transformation that maps the standard brain to the specimen to be segmented. This transformation is then used to: segment the brain from nonbrain tissue; compute prior probabilities for each class at each voxel location and find an appropriate automatic initialization. 3) Finally, a novel algorithm is presented which is a variant of the expectation-maximization procedure, that incorporates a fast and accurate way to find optimal segmentations, given the intensity models along with the spatial coherence assumption. Experimental results with both synthetic and real data are included, as well as comparisons of the performance of our algorithm with that of other published methods.

Tumores del sistema nervioso central. Revisión de cuatro años. (912 casos de autopsias) en el Hospital México / Central nervous system tumor. Review of four years. (912 cases of autopsies) in the Hospital Mexico

En general no existen datos de la frecuencia y características patológicas de los tumores primarios del sistema nervioso en Costa Rica. Se revisaron 912 autpsias, de 19 (2.08 por ciento) tumores un 79 por ciento fueron mujeres y 21 por ciento varones, con promedio de edad de 49.8 años. Los tipos de tumores más frecuentes fueron meningioma (37 por ciento) y glioblastoma (26 por ciento) siendo ambos mas comunes en mujeres.

Do the four clades of the mtDNA haplogroup L2 evolve at different rates?

Forty-seven mtDNAs collected in the Dominican Republic and belonging to the African-specific haplogroup L2 were studied by high-resolution RFLP and control-region sequence analyses. Four sets of diagnostic markers that subdivide L2 into four clades (L2a-L2d) were identified, and a survey of published African data sets appears to indicate that these clades encompass all L2 mtDNAs and harbor very different geographic/ethnic distributions. One mtDNA from each of the four clades was completely sequenced by means of a new sequencing protocol that minimizes time and expense. The phylogeny of the L2 complete sequences showed that the two mtDNAs from L2b and L2d seem disproportionately derived, compared with those from L2a and L2c. This result is not consistent with a simple model of neutral evolution with a uniform molecular clock. The pattern of nonsynonymous versus synonymous substitutions hints at a role for selection in the evolution of human mtDNA. Regardless of whether selection is shaping the evolution of modern human mtDNAs, the population screening of L2 mtDNAs for the mutations identified by our complete sequence study should allow the identification of marker motifs of younger age with more restricted geographic distributions, thus providing new clues about African prehistory and the origin and relationships of African ethnic groups.

MtDNA from extinct Tainos and the peopling of the Caribbean.

Tainos and Caribs were the inhabitants of the Caribbean when Columbus reached the Americas; both human groups became extinct soon after contact, decimated by the Spaniards and the diseases they brought. Samples belonging to pre-Columbian Taino Indians from the La Caleta site (Dominican Republic) have been analyzed, in order to ascertain the genetic affinities of these groups in relation to present-day Amerinds, and to reconstruct the genetic and demographic events that took place during the peopling of the Caribbean. Twenty-seven bone samples were extracted and analyzed for mtDNA variation. The four major Amerindian mtDNA lineages were screened through amplification of the specific marker regions and restriction enzymatic digestion, when needed. The HVRI of the control region was amplified with four sets of overlapping primers and sequenced in 19 of the samples. Both restriction enzyme and sequencing results suggest that only two (C and D) of the major mtDNA lineages were present in the sample: 18 individuals (75%) belonged to the C haplogroup, and 6 (25%) to the D haplogroup. Sequences display specific substitutions that are known to correlate with each haplogroup, a fact that helped to reject the possibility of European DNA contamination. A low rate of Taq misincorporations due to template damage was estimated from the cloning and sequencing of different PCR products of one of the samples. High frequencies of C and D haplogroups are more common in South American populations, a fact that points to that sub-continent as the homeland of the Taino ancestors, as previously suggested by linguistic and archaeological evidence. Sequence and haplogroup data show that the Tainos had a substantially reduced mtDNA diversity, which is indicative of an important founder effect during the colonization of the Caribbean Islands, assumed to have been a linear migratory movement from mainland South America following the chain configuration of the Antilles.

First European exposure to syphilis: the Dominican Republic at the time of Columbian contact.

Recognition of syphilis in Europe in the late 15th century and its prior absence suggest New World origin. Skeletal populations were examined from sites with documented Columbian contact in the Dominican Republic. Examination of 536 skeletal remains revealed periosteal reaction characteristic of treponemal disease in 6%-14% of the afflicted population. Findings were identical to that previously noted in confirmed syphilis-affected populations and distinctive from those associated with yaws and bejel: it was a low population frequency phenomenon, affecting an average of 1.7-2.6 bone groups, often asymmetric and sparing hands and feet, but associated with significant tibial remodeling. While findings diagnostic of syphilis have been reported in the New World, actual demonstration of syphilis in areas where Columbus actually had contact was missing, until now. The evidence is consistent with this site as the point of initial contact of syphilis and of its subsequent spread from the New World to the Old.

[3H]Spermine binding to synaptosomal membranes from the chick retina.

The binding of [3H]spermine to synaptosomal membranes from chick retina was examined. Saturable specific binding of [3H]spermine to synaptosomal membranes from plexiform layers of retina (P1 and P2) has been characterized, and found to concentrate in the inner plexiform layer compared to the outer plexiform layer (Bmax=9.3 and 37 pmol/mg protein for P1 and P2, respectively). Kinetics of specific [3H]spermine binding yield a sigmoidal saturation curve, indicating positive cooperativity (nH: 2.4 and 3.2 for P1 and P2, respectively) with high affinity: Kapp=61 and 67 nM for P1 and P2. The time required to attain equilibrium at room temperature was less than 5 min in both fractions. Dose-response curves for spermine, spermidine, and diethylene-triamine (DET) show different potencies for inhibiting [3HDET. Our results support a role for polyamines (PA) as neurotransmitters or neuromodulators in the vertebrate retina.

Toxic effects of acetylcholinesterase on neuronal and glial-like cells in vitro.

Acetylcholinesterase (AChE), the enzyme involved in the hydrolysis of the neurotransmitter acetylcholine, has been implicated in non-cholinergic actions which may play a role in neurodegenerative diseases such as Alzheimer's disease. To study the potential cytotoxicity of brain AChE, the effects of affinity purified AChE were analyzed on neuronal (Neuro 2a) and glial-like (B12) cells. LDH release and MTT reduction assays showed that AChE was toxic; the toxicity was dependent on the enzyme concentration, time of incubation and cellular density. The toxic effect of AChE was not related to its catalytic activity, since the anti-cholinesterase drug BW284C51 and heat inactivation were unable to block the effects of the enzyme. When cells were incubated at 4 degrees C, toxicity was completely blocked, in contrast to cells incubated at 37 degrees C. The presence of serum in the culture medium inhibited the toxic effects of AChE. Cytoplasmic shrinkage, condensation and fragmentation of nucleus as well as DNA strand breaks detected with the TUNEL technique indicated that apoptotic cell death is involved in the effect of AChE. Considering that we have previously shown that AChE promotes the assembly of beta-amyloid peptide into neurotoxic amyloid fibrils, it is conceivable that the neurotoxicity of AChE shown here may play a role in the neuronal degeneration observed in Alzheimer's disease.

Responses induced by tacrine in neuronal and non-neuronal cell lines.

Alzheimer's disease (AD) is associated with a reduction in cholinergic activity as a result of specific neuronal loss. Current potential treatments for the disease include both cholinomimetic drugs and anticholinesterase inhibitors. One of the drugs approved by the FDA is tacrine (9-amine-1,2,3,4 tetrahydroacridine; THA), a strong acetylcholinesterase (AChE) inhibitor. We have studied the effects of tacrine on glial and neuronal cells in culture assessing cell survival and viability and morphology. Lactate dehydrogenase (LDH) activity and methylthiazol-diphenyl-tetrazolium (MTT) reduction were used as toxicity indicators. We found that tacrine toxicity on rat B12 glial cells and mouse Neuro 2A cells was strongly dependent on its concentration (up to 500 microM) and time of exposure. The toxic effect was not prevented by serum factors nor by bovine serum albumin. Fluorescein-conjugated phalloidin was used to examine the arrangement of actin filaments at substrate adhesion regions and cell-cell contacts. Primary events following exposure to tacrine included changes in cell morphology, disappearance of actin filament bundles, and disruption of focal adhesion contacts. At concentrations between 10 and 50 microM, tacrine induced neurite outgrowth in Neuro 2A cells, an effect that was not observed in B12 cells, suggesting that certain tacrine effects could be specific for neuronal cells. Although similar trends of response were observed for both cell types, some differences between undifferentiated and differentiated cells were apparent.

Stable complexes involving acetylcholinesterase and amyloid-beta peptide change the biochemical properties of the enzyme and increase the neurotoxicity of Alzheimer's fibrils.

Brain acetylcholinesterase (AChE) forms stable complexes with amyloid-beta peptide (Abeta) during its assembly into filaments, in agreement with its colocalization with the Abeta deposits of Alzheimer's brain. The association of the enzyme with nascent Abeta aggregates occurs as early as after 30 min of incubation. Analysis of the catalytic activity of the AChE incorporated into these complexes shows an anomalous behavior reminiscent of the AChE associated with senile plaques, which includes a resistance to low pH, high substrate concentrations, and lower sensitivity to AChE inhibitors. Furthermore, the toxicity of the AChE-amyloid complexes is higher than that of the Abeta aggregates alone. Thus, in addition to its possible role as a heterogeneous nucleator during amyloid formation, AChE, by forming such stable complexes, may increase the neurotoxicity of Abeta fibrils and thus may determine the selective neuronal loss observed in Alzheimer's brain.

Lomefloxacino vs. trimetoprim/sulfametoxazol en el tratamiento de la prostatitis bacteriana crónica / Lomefloxacine vs. trimethoprim-sulfametoxazole in the treatment of chronic bacterial prostatitis

Se realizó un estudio multicéntrico, prospectivo y comparativo con distribución al azar para comparar la eficacia y la seguridad de lomefloxacino (LMF) con la de trimetoprim/sulfametoxazol (TMP/SMX) en el tratamiento de la prostatitis bacteriana crónica. El estudio se efectuó en tres centros hospitalarios, y abarcó a un total de 30 pacientes adultos del sexo masculino con diagnósticos clínicos y bacteriológico confirmados. Los pacientes se distribuyeron al azar para recibir LMF a la dosis de 400 mg una vez al día (n = 15), o TMP/SMX a la de 160/800 mg dos veces al día (n = 15) durante seis semanas. Se valoraron los aspectos de seguridad y eficacia antes del tratamiento, durante el mismo y una vez terminado éste mediante cultivos de orina pruebas de laboratorio y valoración clínica, incluso hasta dos y cuatro meses después del tratamiento. Se logró erradicación bacteriológica en 92.3 por ciento de los pacientes tratados. con LMF y en 84.6 por ciento de los que recibieron TMP/SMX (p> 0.05). Se logró un buen resultado clínico en 100 por ciento de los pacientes que recibieron LMF o TMP/SMX. Ambas evaluaciones se realizaron cinco a nueve días después de terminar el tratamiento. Los agentes patógenos que con mayor frecuencia se aislaron fueron Escherichia coli (43.3 por ciento), estafilococo coagulasa negativo (20 por ciento), Staphylococcus saprophiticus (13.3 por ciento) y Enterococcus sp. (13.3 por ciento). Los efectos adversos se consideraron leves, y los experimentaron un paciente que recibió LMF y dos que tomaron TMP/SMX

Monitoring the effacement of the uterine cervix by transperineal sonography: a new perspective.

The objective of this study is to monitor the process of effacement of the uterine cervix and demonstrate that transperineal sonography is the appropriate technique for this purpose. Eighty-six patients with normal, term pregnancies were studied at the beginning of labor. Transperineal sonography was performed in transverse and longitudinal planes. After the initial examination, patients were reexamined several times during a 1 to 4 hour period. We observed a progressive shortening of the canal and the synchronous opening of a funnel-shaped internal cervical os. When the funneling process reached the lower end of the cervix, both orifices fused, completing the process of effacement. The dilatation of the external os, which remained stationary during initial phase, increases very quickly once the effacement has been completed. Transperineal sonography efficiently imaged the changes described here.

[Anticoagulation in hemodialysis with a single dose of low molecular weight heparin]. / Anticoagulación en hemodiálisis con dosis única de heparina de bajo peso molecular.

The aim of this work was to compare the benefits and problems of low molecular weight heparin use in chronic hemodialysis, compared to conventional heparin. We studied 35 patients that received low molecular weight heparin (Enoxaparine, molecular weight 4000) during 115 consecutive hemodialysis procedures and conventional heparin during the subsequent 35 procedures. We assess the heparin dose, partial thromboplastin time before dialysis and at 3 and 120 min during the procedure, arterio-venous fistula compression time, clot formation in the circuit and residual volume of filters. Median total dose of conventional heparin was 6289 U (range 3000-10000) compared to 5555 U (range 2000-8000) of low molecular weight heparin. When the dose was calculated per kg of body weight, it was lower for low molecular weight heparin than for conventional heparin (87.8 U (range 33-100) vs 100 U (range 50-176)). Partial thromboplastin time achieved was lower with low molecular weight heparin, compared with conventional heparin, at 3 (64.26 vs 125.2 sec) and 120 min (39.1 vs 84.45 sec). Clot formation, arteriovenous fistula compression time and residual volume of filters were similar for both types of heparin. It is concluded that a single dose of low molecular weight heparin simplifies anticoagulation during hemodialysis, modifies less the partial thromboplastin time and does not alter filter re-utilization.

Investigacion sobre toxicidad hepatica de medicacion antituberculosa / Study of the hepatic toxicity of antituberculouis drugs treatment

El presente trabajo fue realizado en el hospital San Gabriel entre enero a marzo de 1990, con 47 pacientes que fueron estudiados durante su tratamiento en diferentes etapas, y muestra el grado de tolerancia hepatica a medicamentos que deben ser utilizados por largo tiempo y que de acuerdo a reaccion individual es imprevisible el grado de toxicidad que pueda esperarse. Los resultados son alentadores porque no se tuvieron que lamentar grados extremos de toxicidad y solo en tres casos, la suspension temporal del tratamiento

[The evaluation of 1-hydroxypyrene as a bioindicator of industrial exposure to polycyclic aromatic hydrocarbons]. / Evaluación del 1-hidroxipireno como bioindicador de la exposición industrial a los hidrocarburos aromáticos policíclicos.

One hundred and twenty-two workers (16 from a coke production plant, 106 from a graphite electrode manufacturing plant) agreed to participate in this study designed to evaluate the relationship between the exposure to polycyclic aromatic hydrocarbons (PAHS) and the urinary excretion of 1-hydroxypyrene (1-HOP), the main metabolite of pyrene. The results show that the concentration of pyrene in air is highly correlated with total PAHS amount (r = 0.083, p < 0.001), with a the correlation coefficient between 1-HOP and total PAHS of r = 0.72 (p < 0.001). The biological half life of the 1-HOP was determined (18 hrs) and the non interference of smoking habits in relation to 1-HOP urinary was established, concluding that 1-HOP is a suitable bioindicator of the occupational exposure to PAHS.

Transperineal sonography in second trimester to term pregnancy and early labor.

We studied the diagnostic potential of transperineal sonography in 184 pregnant women from midtrimester to term pregnancies and at early labor. In 65 patients in false labor, we established cervical effacement and dilatation. We confirmed the clinical diagnosis of premature rupture of the membranes (PROM) in 27 cases and assessed the placental relationship with the internal cervical os in 20 patients. In 61 women in early labor we measured cervical dilatation, and in 11 patients we looked for details of fetal anatomy. Adequate diagnostic information was obtained in 180 cases (97%). Our results and data from the literature suggest that transperineal sonography is the imaging technique of choice in the situations we studied.