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M Trias

Publications and source records attributed to M Trias.

At least 19 recordsLinked to original sources

Predictive factors for successful laparoscopic splenectomy in immune thrombocytopenic purpura: study of clinical and laboratory data.

BACKGROUND: Laparoscopic splenectomy (LS) offers better short-term results than open surgery for the treatment of immune thrombocytopenic purpura (ITP), but long-term follow-up is required to ensure its efficacy. The remission rate after splenectomy ranges from 49 to 86% and the factors that predict a successful response to surgical management have not been clearly defined. The goal of this study was to determine the preoperative factors that predict a successful outcome following LS. METHODS: From February 1993 to December 2003, LS was consecutively performed in a series of 119 nonselected patients diagnosed with ITP (34 men and 85 women; mean age, 41 years), and clinical results were prospectively recorded. Postoperative follow-up was based on clinical records, follow-up data provided by the referring hematologist, and a phone interview with the patient and/or relative. Univariate and multivariate analyses were performed for clinical preoperative variables to identify predictive factors of success following LS. RESULTS: Over a mean period of 33 months, 103 patients (84%) were available for follow-up with a remission rate of 89% (92 patients, 77 with complete remission with platelet count > 150,000). Eleven patients did not respond to surgery (platelet count < 50,000). Mortality during follow-up was 2.5% (two cases not related to hematological pathology and one case without response to splenectomy). Preoperative clinical variables evaluated to identify predictive factors of response to surgery were sex, age, treatment (corticoids alone or associated with Ig or chemotherapy), other immune pathology, duration of disease, and preoperative platelet count. In a subgroup of 52 patients, we also evaluated the type of autoantibodies and corticoid doses required to maintain a platelet count > 50,000. Multivariate analysis showed that none of the variables evaluated could be considered as predictive factors of response to LS due to the high standard error. CONCLUSION: Long-term clinical results show that LS is a safe and effective therapy for ITP. However, a higher number of nonresponders is needed to determine which variables predict response to LS for ITP.

Adolescent↗

Immediate peritoneal response to bacterial contamination during laparoscopic surgery.

BACKGROUND: Several studies have shown that laparoscopic surgery (LS) minimizes surgical trauma and the immune function is better preserved. Another major advantage of LS is the lower incidence of septic complications. However, several in vitro studies have shown that CO(2) severely impairs macrophage physiology. In theory, this would reduce the ability to respond to peritoneal contamination. However, there is some controversy in view of the evidence of a better preserved peritoneal response to sepsis. This study analyzed the early response of the peritoneum to contamination in a CO(2) ambience. METHODS: A total of 192 CD-1 mice were distributed in three groups: group 1, laparotomy (LAP, n = 64); group 2, CO(2) laparoscopy (CO(2)-LC, n = 64); and group 3, wall lift laparoscopy (WL-LC, n = 64). Mice in each group were randomized to receive 1 ml of Escherichia coli suspension (1 x 10(4) colony-forming units/ml) or saline. Peritoneal fluid was obtained at 1.5, 3, 6, and 12 h after surgery. Monocyte chemoattractant protein-1 (MCP-1), interleukin-6 (IL-6), and prostaglandin E(2) (PGE(2)) were measured. RESULTS: MCP-1 levels were significantly greater and higher earlier in group 2 (CO(2)-LC) than in group 1 (LAP) (p < 0.007). Simultaneously, the increment in the traction group (WL-LC, group 3) was significantly higher (p < 0.002) than after laparotomy, with no differences in group 2 (CO(2)-LC). When a contamination was added to the laparotomy subgroup, there was a significant increase compared to the group without contamination (p < 0.5). MCP-1 modifications after contamination in the LAP group were statistically significant and appeared later than in the WL-LC (p < 0.002) and CO(2)-LC groups (p < 0.02). For IL-6, the three models presented a significant increase in the noncontaminated groups. This occurred significantly later in the LAP group. Simultaneously, the increase in IL-6 occurred earlier and was significantly higher in the WL-LC group compared to the LAP group (p < 0.003), without differences between CO(2)-LC and wall lift groups. Significant differences between contaminated and noncontaminated subgroups were only observed in the LC-CO(2) groups. When contaminated, the traction model sustained a higher and earlier rise in IL-6 levels compared to the LAP and LC-CO(2) groups (p < 0.001). For PGE(2), The three models showed a significant increase in PGE(2) levels in the noncontaminated groups. However, there were no significant differences between them. In the contaminated groups, there was no statistical difference between the groups. CONCLUSION: Despite a transient impairment of the immediate peritoneal response to a septic challenge, the degree of injury with LS is lower than that with open surgery, and abdominal infection can therefore be better controlled.

Abdomen↗

Multimedia article. Laparoscopic treatment of chronic sigmoid volvulus in a young adult.

INTRODUCTION: Sigmoid volvulus is responsible for 8% of all intestinal obstructions. The most frequent presentation is in the elderly, with it occurring exceptionally in young people. Surgical resection is mandatory to prevent recurrence. Laparoscopic maneuvers in the long and distended bowel are difficult, and not much experience with these procedures has been reported. MATERIALS AND METHODS, AND RESULTS: A 21-year-old man with antecedents of constipation had two episodes of rectal prolapse, and one episode of acute volvulation treated with decompressive endoscopy. A laparoscopic exploration was performed for definitive treatment. Transanal intubation with a large-bore tube permitted deflation of the bowel. A deep Douglas's pouch was observed with a mobile sigmoid loop that intussuscepted the rectum. A proctosigmoidectomy including the 5 cm of the upper rectum was performed without incident. CONCLUSION: Laparoscopic management of suboclusive colonic volvulus is feasible. Intraopertive transanal intubation permits deflation the loop and facilitates manipulation.

Adult↗

Mid term analysis of safety and quality of life after the laparoscopic repair of paraesophageal hiatal hernia.

BACKGROUND: Initial experience with the laparoscopic repair of paraesophageal and type III mixed hiatal hernias showed that it is safe and feasible, with excellent immediate and short-term results. However, after a longer follow-up, a recurrence rate of < or =40% has been demonstrated. Data related to the outcome of paraesophageal hernia repair and the recurrence rate are still lacking. Quality-of-life scores may offer a better means of assessing the impact of surgical treatment on the overall health status of patients. Therefore, we performed prospective evaluation of anatomic and/or symptomatic recurrences after paraesophageal or large hiatal hernia repair. In addition, we investigated the correlation between recurrence and the patient's quality of life. METHODS: All patients after who had undergone repair of paraesophageal of mixed hiatal hernia were identified prospectively from a database consisting of all patients who had had laparoscopic operations for gastroesophageal pathology at our hospital between February 1998 and December 2002. The preoperative symptoms were taken from patients' clinical files. In March 2003, all patients with > or =6 months of follow-up had a barium swallow and were examined for radiological and clinical signs of recurrence. Thereafter, the patients' quality of life after surgery was evaluated using three standard questionnaires (Short Form 36 [SF-36], Glasgow Dyspepsia Severity Score [GDSS], and Gastrointestinal Quality of Life Index [GIQLI]. RESULT: During the study period, 46 patients had been operated on. The mean age was 63 years (range, 28-93). Thirty seven of them had a follow-up of > or =6 months. Eight patients (21%) had postoperative gastrointestinal symptoms. Barium swallow was performed in 30 patients (81%) and showed a recurrence in six of them (20%). According to SF-36 and GDSS, the patients' postoperative quality of life reached normal values and did not differ significantly from the standard values for the Spanish population of similar age and with similar comorbidities. Successfully operated patients reached a GIQLI value comparable to the standard population. However, symptomatic patients had significantly lower GIQLI scores than the asymptomatic or the Rx-recurrent group. CONCLUSION: The laparoscopic treatment of large paraesophageal and mixed hiatal hernias is not only feasible and safe but also offers a good quality of life on a midterm basis. However, the anatomic and functional recurrence rate is high. The next step is to identify the subset of patients who are at risk of failure and to establish technical alternatives that would ensure the durability of the repair.

Adult↗

Impact of seasonal variation on treatment of swine wastewater.

Swine wastewater (agricultural wastewater) is normally stored in a storage holding tank for a certain time before released to the other treatment units, such as anaerobic lagoon and aerobic wetland. One of the characteristics for this treatment approach is that all the processes are open systems that are generally more passive in design and operation. As a consequence, seasonal variability including temperature and precipitation can have substantial impact on treatment efficacy and effluent water quality. This paper examines seasonal impacts of temperature on swine wastewater quality and treatment efficacy at a farm in East Leicester, Nova Scotia, Canada. During warm temperatures denitrification was noticeable in the anaerobic conditions, which would reduce the TSS removal rate from 76.6% in moderate temperatures to 42.1% in the warmest period recorded. Rainfall improved final effluent water quality, although this was shown to be through dilution rather than improvement of treatment efficacy. Following precipitation events the contaminant removals were negatively impacted in the aerobic lagoon, as BOD5 removal decreased from 61.6% before rainfall to 41.5% after rainfall, TSS from 71.4% to 59.3%, VSS from 73.4% to 59.3%, TKN from 59.9% to 42.1%, and NH4+ -N from 51.3% to 41.6%. In comparison to the aerobic conditions, the removal rates were increased for anaerobic condition with the rainfall dilution (e.g., TSS from 18.2% to 34.3%), which lead to an overall treatment improvement for the entire system. Thus the case study data presented in this paper provides an assessment of the operational and design issues that are particularly relevant for passive treatment systems that are used in the agriculture industry.

Agriculture↗

Optimizing settling conditions for treatment of liquid hog manure.

Sedimentation is a widely used separation method for treating agricultural waste. There are several chemical and biological characteristics, which can affect the settling behavior and liquid waste. The optimization of cation balances and potential for nitrification are among these processes. In addition to sedimentation, it can also affect the dewaterability of the samples. Liquid hog manure was used during the laboratory based experiments to investigate the effects of Ca2+ and Mg2+ ions and nitrification inhibition on the overall settling and dewatering characteristics. The results indicated that settling and dewatering characteristics improved during the course of the experiments. However, the improvement in settling and dewatering characteristics was inconsistent and not statistically significant. Cation addition in aerated reactor increased the highest settling velocity (94%). The improvement in dewaterability, as quantified by capillary suction time, was also not consistent. The greatest filterability observed in the supernatant was a capillary suction time of 40 s for a M:D ratio of 2:1. Initial NH 4 + concentration was more important than the nitrification inhibitor, as the presence of nitrification inhibitor increased the nitrification rate by over 300% because of the high initial NH 4 + concentration and low volatile suspended solid. The results from these experiments provide the basis for further field evaluation of cation optimization.

Agriculture↗

Hand-assisted laparoscopic splenectomy (HALS) in cases of splenomegaly: a comparison analysis with conventional laparoscopic splenectomy.

BACKGROUND: Laparoscopic splenectomy (LS) is considerably more difficult to perform when the spleen is enlarged. The new technique of hand-assisted designed technique aimed to assist laparoscopic surgery allows the surgeon to insert his or her hand into the abdomen while maintaining the pneumoperitoneum, thus recovering the tactile sensation lost in conventional laparoscopic surgery. OBJECT: In this study, we compared the immediate results of conventional LS and hand-assisted LS (HALS) in cases of splenomegaly. METHODS: Between February 1993 and August 2001, 200 LS were attempted at two university hospitals. In 56 cases, splenomegaly (final spleen weight >700 g) was observed clinically or detected on radiological examination. We compared the first 36 patients operated on by conventional LS (group I) with the last consecutive 20 patients, who underwent HALS (group II). The study parameters were operative time, conversion rate, transfusion rate, morbidity and length of hospital stay. RESULTS: The groups were comparable in terms of age (58 +/- 13 [ranges, l9-82] vs 58 +/- 16 years [range, 44-84] (ns), diagnosis, and spleen weight (1425 +/- 884 [range, 700-3400]) vs 1753 +/- 1124 g [range, 720-4500] (ns). HALS was associated with less morbidity (36% vs 10%) (ns), a shorter operative time (177 +/- 52 [range, 95-300]) vs 135 +/- 53 min [range, 85-270] (p <0.009), and a shorter hospital stay (6.3 +/- 3.3 [range, 3-14]) vs 4 +/- 1.2 [range, 2-7] days (p <0.05). CONCLUSION: In cases of splenomegaly, HALS assisted laparoscopic surgery significantly facilitates the surgical maneuvers during LS while maintaining the advantages of a purely laparoscopic approach.

Adult↗

Evaluation of risk of splenosis during laparoscopic splenectomy in rat model.

Laparoscopic splenectomy (LS) is an alternative to open surgery. However, there is a theoretic risk of splenosis and abdominal cavity dissemination of splenic cells if the splenic capsule is broken, as seen by experimental evidence of tumoral cell mobilization by the pneumoperitoneum. We evaluated the features of splenosis after splenectomy operated via an open approach or under laparoscopic control in an experimental model in the rat. A total of 65 Sprague-Dawley rats were distributed in seven groups that included the open approach, CO2 pneumoperitoneum LS, or wall lift LS with or without a splenic graft. Splenic function was evaluated 90 day later through (1) scintigraphy with Tc-labeled heat-damaged erythrocytes; (2) determination of circulating "pitted" cells; and (3) analysis of the distribution of splenic pulp in the peritoneal cavity. Scintigraphy did not show viable residual tissue in any group after splenectomy; splenic activity in the splenic fossa was observed in 40% of the animals with grafts. Splenectomy increased the "pit" cell count, but it was reduced to normal values with a splenic graft. Necropsy showed normal splenic tissue in the splenic fossa in 100% of animals with a graft. Abdominal implants were observed significantly more frequent after CO2 LS than after the open surgery or a wall lift LS (80% vs. 20% vs. 30%; p < 0.05). In addition, trocar site implants were observed with CO2 LS (n = 3) or wall lift LS (n = 2), whereas there were no implants in the wound in the open group. We conclude that in an experimental rat model the pneumoperitoneum may facilitate abdominal splenosis after LS if the splenic capsule is ruptured or if splenic tissue spills compared with surgery without gas (open or laparoscopic).

Abdominal Muscles↗

Laparoscopic surgery and surgical infection.

Laparoscopic surgery (LS) has improved our knowledge of some aspects of surgical physiopathology. Other advantages include a lower incidence of postoperative infections, as evidenced by a lower inflammatory response which is related to a better preserved immune response to infection. But, the differential aspects of LS may influence the intraperitoneal environment and, in case of infection, must be evaluated in two different situations: during clean and potentially-contaminated surgery or in the presence of established infection. The most important differential factors of LS are the pneumoperitoneum and the use of CO2. The influence of both these on the evolution of an intraperitoneal infecton has been of interest in recent years. Our department developed an experimental study with mice to evaluate the local and systemic inflammatory response to perioperative intra-abdominal contamination with a known inoculum of Escherichia coli. The animals were distributed in four groups: control, laparotomy, laparoscopy with CO2 pneumoperitoneum, and laparoscopy with wall traction. Peritoneal liquid and blood cultures such as peritoneal and systemic cytokine levels were analyzed. The results showed a better tolerance to perioperative contamination in LS groups while the CO2 pneumoperitoneum had no influence. But, in the presence of peritonitis, an elevated CO2 pneumoperitoneum can be dangerous and the operative time is an important factor to be considered. The literature is reviewed on the relationship between LS and surgical infection.

Animals↗

Hand-assisted laparoscopic splenectomy.

Hand-assisted laparoscopic surgery (HALS) permits recovery of the tactile sensation and facilitates manipulation of solid organs. Our preliminary experience in laparoscopic splenectomy (LS) shows its advantages, with a substantial reduction of operative time, while maintaining the advantages of a less aggressive surgical approach. The role of HALS in cases of splenomegaly or trauma seems to be clear. It can also be considered as an alternative to conventional conversion in cases of intraoperative complications or unclear anatomy. The role of HALS for normal-sized spleens is more controversial because there is a well-systematized, conventional LS technique available, which is followed by optimal clinical outcome LS in hands of a skilled surgeon.

Adult↗

Impact of hematological diagnosis on early and late outcome after laparoscopic splenectomy: an analysis of 111 cases.

BACKGROUND: Laparoscopic splenectomy (LS) is now regarded as the treatment of choice for autoimmune thrombopenia (ITP). However, there have been few reports describing the application of LS to other splenic diseases, such as malignant entities and conditions associated with splenomegaly. Hematological diseases have specific clinical features that can influence immediate outcome after LS. Although the long-term effects of LS are unknown, a risk of splenosis has been suggested. Therefore, we designed a study to analyze the impact of primary hematological disease on immediate and late outcome in a prospective series of LS patients. METHODS: We performed a prospective analysis of 111 LS done between February 1993 and March 1999. The patients were classified by hematological indications into the following four groups: (a) group 1, low platelet count. This group was further subdivided into group 1A, idiopathic thrombocytopenic purpura (ITP) (n = 48) and group 1B, HIV-related ITP (n = 8); (b) group 2, anemia. This group was further subdivided into group 2A, autoimmune hemolytic anemia (n = 8), and group 2B, spherocytosis (n = 11); (c) group 3, malignancy (n = 28); and (d) group 4, others (n = 8). Immediate outcomes were recorded prospectively. Hematological status and late complications were reviewed after a mean follow-up of 24 +/- 18 months. RESULTS: There were no significant differences between the groups in terms of conversion, transfusion requirements, and morbidity, although transfusion and morbidity were slightly higher in group 3. However, hospital stay was significantly longer in groups 3 and 4 than in groups 1 and 2. Long-term follow-up showed satisfactory hematological results in >/=75% of patients (group 1A, 82%; group 1B, 88%; group 2A, 88%; group 2B, 100%; group 3, 75%; group 4, 88%). Overall, late morbidity was 8.3% and mortality was 6.2%, mainly due to deaths in group 4 (six of 22 patients). CONCLUSION: LS is a safe and reproducible procedure for most hematological indications, with a similar immediate outcome for benign diseases and a long-term hematological response comparable to the standard results that have been observed in open series.

Chi-Square Distribution↗

Applicability of laparoscopic surgery for colorectal disease.

BACKGROUND: The advantages of laparoscopic colorectal surgery for selected patients have been well established. However, the applicability of laparoscopic surgery in the whole population of patients with colorectal disease is not well known. METHODS: A single-institution medical records review of 269 patients subjected to colorectal surgery was made. Of these, 206 open colorectal procedures were performed, and data were reviewed retrospectively. In addition, 63 patients were subjected to laparoscopy, and their data were recorded prospectively. An analysis of the existence of factors that contraindicate laparoscopic colorectal surgery was done. These factors were of two types: absolute (urgent intervention, severe cardiopulmonary disease, advanced liver cirrhosis, tumor invasion into adjacent organs, simultaneous major surgery) and relative (midrectal tumors, tumors in the transverse colon, bulky tumors, more than two previous infraumbilical operations, previous intestinal surgery, and previous peritonitis). RESULTS: Factors that could contraindicate the laparoscopic approach were found in 118 patients (44%). The most common were urgent intervention (40%), midrectal tumors (19%), locally advanced cancer (13%), previous intestinal surgery (13%), and tumors >10 cm (6%). We considered 25% of the contraindications to be absolute and 19% relative. Taking these exclusion criteria into consideration when selecting patients for laparoscopic surgery, the conversion rate in our initial laparoscopic series (63 cases) was 13%. CONCLUSION: The indication for laparoscopic surgery for patients with colorectal disease is superior to 60% (absolute 56%, relative 81%). When using appropriate selection criteria, the conversion rate may be maintained below 10%. Preoperative selection of patients with colorectal disease allows optimal use of the advantages of laparoscopic surgery.

Adult↗

NAD(P)H:quinone oxidoreductase-dependent risk for colorectal cancer and its association with the presence of K-ras mutations in tumors.

NAD(P)H:quinone oxidoreductase (NQO1) is a polymorphic enzyme involved in the detoxification of potentially mutagenic and carcinogenic quinones. The homozygous C609T NQO1 genotype resulting in loss of reductase activity is found in 2-20% of individuals. In the present study, the NQO1-dependent risk for sporadic colorectal cancer (CRC) was studied in 247 incident CRC cases and 296 hospital-based controls recruited during 1996-1997. Four subgroups of cases were studied: (i) all CRCs; (ii) a molecular CRC subgroup (n = 117, cases with molecular tumor analyses); (iii) within the molecular subgroup those tumors with K-ras mutations in codon 12 (CRC K12); (iv) within the molecular subgroup those tumors with K-ras mutations in codon 13 (CRC K13). The C609T NQO1 genotype was found to be twice as prevalent in all CRC patients (6.8%) compared with controls (3%) and six times more common in the subset CRC K12 (20%). Multivariant analyses in the overall population of 247 cases and 296 controls showed a significant age and gender adjusted risk for CRC associated with the C609T NQO1 genotype (OR 2.9, 95% CI 1.19-6.97; P = 0.01) or with any variant genotype (the low activity allele frequency, i.e. heterozygotes plus homozygotes) (OR 1.41, 95% CI 1.02-1.92; P = 0.03). Within cases of the molecular subgroup (n = 117) the C609T NQO1 genotype was associated with the presence of K-ras codon 12 mutation (OR 6.5 95%, CI 1.39-34.9; P = 0.003). Logistic regression showed an age and gender adjusted risk for K-ras codon 12 mutant CRC associated with the C609T NQO1 genotype (OR 10.5, 95% CI 2.99-36.7; P: = 0.0002) or with any variant NQO1 genotype (OR 2.23, 95% CI 1.23-4.00; P = 0.007) compared with the control group. Genetically determined variations in NQO1 may modify the risk for CRC and these risks may be greatest for tumors containing K-ras codon 12 mutations. CRC with K-ras codon 12 mutations may represent a distinct and etiologically more homogeneous subtype of the disease, which may be associated with toxicants that are metabolized via a NQO1-dependent pathway.

Age Factors↗

Correlations of partial and extensive methylation at the p14(ARF) locus with reduced mRNA expression in colorectal cancer cell lines and clinicopathological features in primary tumors.

p14(ARF) is a putative tumor suppressor gene thought to modify the levels of p53. CpG sites within the 5'-flanking region and exon 1beta of p14(ARF) are targets of aberrant methylation and transcriptional silencing in human colorectal cancer (CRC). Here we have developed methylation-specific polymerase chain reaction (MSPCR) methods to detect methylation of CpG sites in p14(ARF) in CRC cell lines and primary CRC tumors, and correlated p14(ARF) mRNA expression with methylation in CRC cell lines using competitive quantitative reverse transcription-polymerase chain reaction methods. Ten CRC cell lines were studied; three (DLD-1, HCT15 and SW48) showed extensive methylation and six (Colo320, SW480, HT29, Caco2, SW837 and WiDr) were unmethylated; the other cell line, LoVo, showed partial methylation that affected exon 1beta but not the immediate upstream CpG sites. p14(ARF) mRNA was expressed at extremely low levels in fully methylated cell lines and at 10(4)- to 10(5)-fold higher levels in unmethylated cell lines. p14(ARF) expression in the partially methylated LoVo cell line was intermediate. Treatment of LoVo cells with 2 microM 5-aza-2'-deoxycytidine for 72 h was associated with marked (100-fold) induction of mRNA levels. Of 119 primary CRCs, 18% contained p14(ARF) methylation, although partial methylation was the most common pattern observed (in 67% of methylated tumors). Methylation of p14(ARF) was often accompanied by p16(INK4a) methylation; however, 50% of p14(ARF) methylated tumors contained unmethylated p16(INK4a). Methylation at p14(ARF) was associated with female gender, greater age, proximal anatomic location and poor differentiation, but not stage at diagnosis. A two-step MSPCR method for assaying p14(ARF) methylation in human tumors is described.

Adult↗