Enamel and dentin mineralization in familial hypophosphatemic rickets: a micro-CT study

Objectives:

The aim of the present study was to analyse the mineralization pattern of enamel and dentin in patients affected by X-linked hypophosphatemic rickets (XLHR) using micro-CT (µCT), and to associate enamel and dentin mineralization in primary and permanent teeth with tooth position, gender and the presence/absence of this disease.

Methods:

19 teeth were collected from 5 individuals from the same family, 1 non-affected by XLHR and 4 affected by XLHR. Gender, age, tooth position (anterior/posterior) and tooth type (deciduous/permanent) were recorded for each patient. Following collection, teeth were placed in 0.1% thymol solution until µCT scan. Projection images were reconstructed and analysed. A plot profile describing the greyscale distance relationship in µCT images was achieved through a line bisecting each tooth in a region with the presence of enamel and dentin. The enamel and dentin mineralization densities were measured and compared. Univariate ANOVA and post hoc Tukey tests were used for all comparisons.

Results:

Teeth of all affected patients presented dentin with a different mineralization pattern compared with the teeth of healthy patients with dentin defects observed next to the pulp chambers. Highly significant differences were found for gray values between anterior and posterior teeth (p < 0.05), affected and non-affected (p < 0.05), as well as when position and disease status were considered (p < 0.05).

Conclusions:

In conclusion, the mineralization patterns of dentin differed when comparing teeth from patients with and without FHR, mainly next to pulp chambers where areas with porosity and consequently lower mineral density and dentin defects were found.     

Assessment of a Polyester-Covered Nitinol Stent in the Canine Aorta and Iliac Arteries

Purpose: To evaluate the patency and healing characteristics of a woven polyester fabric-covered stent in the canine model. Methods: Twenty-four self-expanding covered stents were placed in the infrarenal aorta and bilateral common iliac arteries of eight dogs and evaluated at 1 (n = 2), 3 (n = 2), and 6 (n = 4) months. Stent assessment was done using angiography prior to euthanasia, and light and scanning electron microscopy. Results: Angiographically, just prior to euthanasia, 8 of 8 aortic and 14 of 16 iliac endovascular covered stents were patent. Histologically, the stented regions showed complete endothelialization 6 months after graft implantation. A neointima had formed inside the stented vessel regions resulting in complete encasement of the fabric-covered stent by 3 months after graft implantation. Medial compression with smooth muscle cell atrophy was present in all stented regions. Explanted stent wires, examined by scanning electron microscopy, showed pitting but no cracks or breakage. Conclusion: The covered stent demonstrated predictable healing and is effective in preventing stenosis in vessels 10.0 mm or greater in diameter but does not completely preclude stenosis in vessels 6.0 mm or less in diameter.     

Aortic Branch Artery Pseudoaneurysms Associated with Intramural Hematoma: When and How to Do Endovascular Embolization

Purpose

To describe when and how to perform endovascular embolization of aortic branch artery pseudoaneurysms associated with type A and type B intramural hematoma (IMH) involving the descending thoracic and abdominal aorta (DeBakey I and III) that increased significantly in size during follow-up.

Materials and Methods

Sixty-one patients (39 men; mean ± standard deviation age 66.1 ± 11.2 years) with acute IMH undergoing at least two multidetector computed tomographic examinations during follow-up for 12 months or longer were enrolled. Overall, 48 patients (31 men, age 65.9 ± 11.5) had type A and type B IMH involving the descending thoracic and abdominal aorta (DeBakey I and III).

Results

Among the 48 patients, 26 (54 %; 17 men, aged 64.3 ± 11.4 years) had 71 aortic branch artery pseudoaneurysms. Overall, during a mean follow-up of 22.1 ± 9.5 months (range 12–42 months), 31 (44 %) pseudoaneurysms disappeared; 22 (31 %) decreased in size; two (3 %) remained stable; and 16 (22 %) increased in size. Among the 16 pseudoaneurysms with increasing size, five of these (three intercostal arteries, one combined intercostobronchial/intercostal arteries, one renal artery), present in five symptomatic patients, had a significant increase in size (thickness >10 mm; width and length >20 mm). These five patients underwent endovascular embolization with coils and/or Amplatzer Vascular Plug. In all patients, complete thrombosis and exclusion of aortic pseudoaneurysm and relief of back pain were achieved.

Conclusion

Aortic branch artery pseudoaneurysms associated with type A and type B IMH involving the descending thoracic and abdominal aorta (DeBakey I and III) may be considered relatively benign lesions. However, a small number may grow in size or extend longitudinally with clinical symptoms during follow-up, and in these cases, endovascular embolization can be an effective and safe procedure.     

Changes in serological markers of hepatitis B virus after renal transplantation

An estimated 350 million persons worldwide are chronically infected with hepatitis B virus (HBV). Immunosuppression after renal transplantation seems to enhance viral replication and increase the risk of developing cirrhosis and hepatocellular carcinoma. This retrospective study was performed to assess the prevalence among and serological status of HBV infection after renal transplantation at a single university Brazilian center. Thirty six (4.2%) patients among 850 kidney recipients showed positive HBsAg for more than 6 months; 31 were hepatitis B surface antigen (HBsAg) positive at transplantation. Of the 15 hepatitis B e antigen (HbeAg) positive patients, six had spontaneous HBeAg seroconversion and three also had HBsAg clearance. An additional two showed HBeAg clearance with Lamivudine without seroconversion. Among 15 HBeAg-negative patients, three developed HBeAg reversion with no elevation of alanine transferase (ALT) levels and one had HBsAg clearance. Only one patient had acute exacerbation of hepatitis B (ALT > 20 times normal range) but remained HbeAg negative. During follow-up, five patients became HBsAg positive; two reactivations of resolved hepatitis B, two with previous anti-HBS induced by vaccination, and one with no serological marker for HBV. Lamivudine was prescribed for 16 patients, two of whom had HbeAg clearance without seroconversion and five who developed viral resistance to Lamivudine after a mean of 29.2 months. No hepatocellular carcinoma or deaths related to hepatitis B were seen in this group. In summary, prevalence of HBV in kidney transplant patients was 4.2%. Immunosuppression after renal transplantation in HBV infection led to an increased risk of liver complications and changes in HBV serological status.     

Small-Volume,Fast-Emptying Gastric Pouch Leads to Better Long-Term Weight Loss and Food Tolerance After Roux-en-Y Gastric Bypass

Introduction

Anatomical and functional influences on gastric bypass (GBP) results are often poorly evaluated and not yet fully understood.

Purpose

The purpose of this study is to evaluate the influence of the gastric pouch volume and its emptying rate on long-term weight loss and food tolerance after GBP.

Materials and Methods

Weight loss, food tolerance, pouch volumetry (V) by three-dimensional reconstruction, and pouch emptying rate by 4 h scintigraphy were evaluated in 67 patients. Cutoffs were identified for V and retention percentage (%Ret) at 1 h (%Ret1). From these parameters, the sample was categorized, looking for associations between V, %Ret, weight loss, and food tolerance, assessed by a questionnaire for quick assessment of food tolerance (SS).

Results

PO median follow-up time was 47 months; median V was 28 mL; %Ret at 1, 2, and 4 h were 8, 2, and 1%, respectively. There were associations between V ≤ 40 mL and higher emptying rates up to 2 h (V ≤ 40 mL: %Ret1 = 6, %Ret2 = 2, p = 0.009; V > 40 mL: %Ret1 = 44, %Ret2 = 13.5, p = 0.045). An association was found between higher emptying speed in 1 h and higher late weight loss (WL), represented by lower percentage of excess weight loss (%EWL) regain (p = 0.036) and higher %EWL (p = 0.033) in the group with %Ret1 ≤ 12%, compared to the group %Ret1 ≥ 25%. Better food tolerance (SS > 24), was associated with lower %Ret1 (p = 0.003).

Conclusion

Smaller pouch size is associated with a faster gastric emptying, greater WL maintenance, and better food tolerance. These data suggest that a small pouch with rapid emptying rate is an important technical parameter for good outcomes in GBP.

     

Ischemic colitis: risk factors for eventual surgery

Background

Ischemic colitis is a common disorder often without clear indications for surgical management. The aim of this study was to identify risk factors that predict the need for surgery.

Methods

Patients were identified retrospectively based on International Classification of Disease codes and admission over an 8-year period.

Results

A total of 253 patients presented with ischemic colitis. A total of 205 patients were managed nonsurgically, 12 underwent immediate surgery (within 12 hours of presentation), and 36 had delayed surgery. On univariate analysis, risk factors that predicted delayed surgery were peripheral vascular disease, atrial fibrillation, hypotension, tachycardia, absence of bleeding per rectum, free intraperitoneal fluid on computed tomography scan, intensive care unit admission, vasopressors, mechanical ventilation, and increased lactate level on admission. Intraperitoneal fluid on computed tomography scan and absence of bleeding per rectum were predictive of surgical intervention on multivariate analysis.

Conclusions

In patients with ischemic colitis, several risk factors were associated with the need for subsequent surgery during the same admission. These factors could be used to select patients for immediate surgery before worsening of their clinical condition.     

Unilateral Plantar Flexors Static-Stretching Effects on Ipsilateral and Contralateral Jump Measures

The aim of this study was to evaluate the acute effects of unilateral ankle plantar flexors static-stretching (SS) on the passive range of movement (ROM) of the stretched limb, surface electromyography (sEMG) and single-leg bounce drop jump (SBDJ) performance measures of the ipsilateral stretched and contralateral non-stretched lower limbs. Seventeen young men (24 ± 5 years) performed SBDJ before and after (stretched limb: immediately post-stretch, 10 and 20 minutes and non-stretched limb: immediately post-stretch) unilateral ankle plantar flexor SS (6 sets of 45s/15s, 70-90% point of discomfort). SBDJ performance measures included jump height, impulse, time to reach peak force, contact time as well as the sEMG integral (IEMG) and pre-activation (IEMG_{pre-activation}) of the gastrocnemius lateralis. Ankle dorsiflexion passive ROM increased in the stretched limb after the SS (pre-test: 21 ± 4° and post-test: 26.5 ± 5°, p < 0.001). Post-stretching decreases were observed with peak force (p = 0.029), IEMG (P<0.001), and IEMG_{pre-activation} (p = 0.015) in the stretched limb; as well as impulse (p = 0.03), and jump height (p = 0.032) in the non-stretched limb. In conclusion, SS effectively increased passive ankle ROM of the stretched limb, and transiently (less than 10 minutes) decreased muscle peak force and pre-activation. The decrease of jump height and impulse for the non-stretched limb suggests a SS-induced central nervous system inhibitory effect.

Key points

• When considering whether or not to SS prior to athletic activities, one must consider the potential positive effects of increased ankle dorsiflexion motion with the potential deleterious effects of power and muscle activity during a simple jumping task or as part of the rehabilitation process.
• Since decreased jump performance measures can persist for 10 minutes in the stretched leg, the timing of SS prior to performance must be taken into consideration.
• Athletes, fitness enthusiasts and therapists should also keep in mind that SS one limb has generalized effects upon contralateral limbs as well.

Key words: Athletic training, exercise performance, exercise training, crossover, cross-education     

Predictive factors of recurrence in adenocarcinoma of the esophagogastric junction in the multimodal era

IntroductionAdenocarcinoma of the esophagogastric junction (AEGJ) represents a poor prognostic tumor. We evaluated the recurrence pattern and risk factors associated with recurrence in patients undergoing surgical resection by AEJG.MethodsRecurrences were categorized as locoregional, peritoneal, or distant. These three recurrence groups and a non-recurrence group were compared, and overall survival (OS) and disease-free survival (DFS) for each one was obtained.ResultsWe analyzed 188 patients with curative surgical treatment. Recurrence was observed in 72 (38.3%) patients. Locoregional recurrence was observed in 17 (23.6%); 20 (27.8%) peritoneal recurrence and 35 (48.6%) distant metastasis. DFS was 9, 5, and 8 months, and OS was 21.8, 13.2, and 20.8, respectively. Tumors larger than 5 cm are risk factors for peritoneal recurrence (OR:2.88, p = 0.012). Positive lymph nodes were related to distant metastasis (OR:9.15, p = 0.040), and lymphatic invasion for locoregional recurrence (OR:3.81, p = 0.028).ConclusionAEGJ is associated with high rates of early recurrence.     

Venous skin flaps: an experimental study and report of two clinical distal island flaps

An experimental study of saphenous flaps in 26 dogs is reported, which confirmed the work of Baek et al. (1985) that venous flaps can survive. In addition, it showed that venous island flaps could survive after division of the venous pedicle proximally or distally, or as free flaps, providing through flow was re-established by venous anastomoses. In this study no flaps survived on a single venous pedicle without through flow. Two successful clinical cases of venous flaps are also reported, in which through flow was re-established by a simple venous anastomosis. One of these flaps threatened to become necrotic until the thrombosed anastomosis was successfully redone.     

Atrial flutter termination by overdrive transesophageal pacing and the facilitating effect of oral propafenone

Transesophageal overdrive atrial pacing is effective and safe for atrial flutter termination. The influence of antiarrhythmic drug therapy on this procedure is controversial. In this study, we investigated whether oral propafenone may facilitate this procedure. Thirty patients with type I atrial flutter were randomized into 2 groups in which transesophageal pacing was attempted: group A, without treatment; and group B, after oral administration of propafenone 600 mg. Transesophageal pacing was effective in interrupting atrial flutter in 53% of patients (8 of 15) in group A and in 87% of patients (13 of 15) in group B. A significant lengthening of the flutter cycle was observed with respect to the baseline in patients given propafenone (261 ± 23 vs 217 ± 25, p < 0.01). Sinus rhythm resumed at a shorter paced cycle in group A patients (166 ± 13 vs 187 ± 14 ms, p < 0.01). The transesophageal threshold for stable atrial capture was significantly lower in group A (20.5 ± 0.2 vs 23.3 ± 1.2, p < 0.01). In no patient was the threshold for atrial capture higher than the pain threshold. We did not observe abrupt enhancement of atrioventricular conduction. We conclude that propafenone is effective and safe when used with transesophageal pacing in the termination of atrial flutter. The slowing effect of the drug on intraatrial conduction and the possible stabilizing effect on the reentry circuit appear to be outweighed by the positive effect of propafenone on the excitable gap of the circuit, facilitating its capture and accounting for the beneficial effect of the drug on arrhythmia termination.