Estimating the prevalence of infectious diseases from under-reported age-dependent compulsorily notification databases.

BACKGROUND: National or local laws, norms or regulations (sometimes and in some countries) require medical providers to report notifiable diseases to public health authorities. Reporting, however, is almost always incomplete. This is due to a variety of reasons, ranging from not recognizing the diseased to failures in the technical or administrative steps leading to the final official register in the disease notification system. The reported fraction varies from 9 to 99% and is strongly associated with the disease being reported. METHODS: In this paper we propose a method to approximately estimate the full prevalence (and any other variable or parameter related to transmission intensity) of infectious diseases. The model assumes incomplete notification of incidence and allows the estimation of the non-notified number of infections and it is illustrated by the case of hepatitis C in Brazil. The method has the advantage that it can be corrected iteratively by comparing its findings with empirical results. RESULTS: The application of the model for the case of hepatitis C in Brazil resulted in a prevalence of notified cases that varied between 163,902 and 169,382 cases; a prevalence of non-notified cases that varied between 1,433,638 and 1,446,771; and a total prevalence of infections that varied between 1,597,540 and 1,616,153 cases. CONCLUSIONS: We conclude that the model proposed can be useful for estimation of the actual magnitude of endemic states of infectious diseases, particularly for those where the number of notified cases is only the tip of the iceberg. In addition, the method can be applied to other situations, such as the well-known underreported incidence of criminality (for example rape), among others.

Role of EUS evaluation after endoscopic eradication of esophageal varices with band ligation.

BACKGROUND AND AIMS: Variceal recurrence after endoscopic band ligation (EBL) for secondary prophylaxis is a frequent event. Some studies have reported a correlation between variceal recurrence and variceal rebleeding with the EUS features of paraesophageal vessels. A prospective observational study was conducted to correlate EUS evaluation of paraesophageal varices, azygos vein, and thoracic duct with variceal recurrence after EBL variceal eradication in patients with cirrhosis. METHODS: EUS was performed before and 1 month after EBL variceal eradication. Paraesophageal varices, azygos vein, and thoracic duct maximum diameters were evaluated in predetermined anatomic stations. After EBL variceal eradication, patients were submitted to endoscopic examinations every 3 months for 1 year. We looked for EUS features that could predict variceal recurrence. RESULTS: Thirty patients completed a 1-year endoscopic follow-up. Seventeen patients (57%) presented variceal recurrence. There was no correlation between azygos vein and thoracic duct diameter with variceal recurrence. Larger paraesophageal varices predicted variceal recurrence in both evaluation periods. Paraesophageal varices diameters that best correlated with variceal recurrence were 6.3 mm before EBL (52.9% sensitivity, 92.3% specificity, and .749 area under the receiver operating characteristic curve [AUROC]) and 4 mm after EBL (70.6% sensitivity, 84.6% specificity, and .801 AUROC). CONCLUSIONS: We conclude that paraesophageal varices diameter measured by EUS predicts variceal recurrence within 1 year after EBL variceal eradication. Paraesophageal diameter after variceal eradication is a better recurrence predictor, because it has a lower cut-off parameter, higher sensitivity, and higher AUROC.

Bile duct confluence: anatomic variations and its classification.

Accurate knowledge of the anatomy of the bile ducts is critical for successfully hepato-biliary surgery. We describe the anatomical variations of the confluence of the bile ducts, their branches patterns, frequency and classification. From 1996 to 2011, we have collected data of the bile duct confluence. 2,032 and 1,014 anatomical variations of right and left bile ducts, respectively, were reviewed and classified according to the branching pattern. The frequencies of each type of the right hepatic duct (RHD) were as follows: Type A1-1,247 (61.3%); Type A2-296 (14.5%); Type A3-272 (13.3%); Type A4-124 (6.1%); Type A5-21 (1%) and others-72 (3.5%) and, for the left hepatic duct (LHD) was as follows: Type B1-773 (76.2%); Type B2-153 (15%); Type B3-38 (3.7%); Type B4-9 (0.8%); Type B5-29 (2.8%) and others-12 (1.1%). Atypical branching patterns of both the right and left hepatic ducts were found in 14 and 8%, respectively. The two most common variations of the RHD were right anterior and posterior hepatic ducts join together to form the RHD and trifurcation where the RHD is absent and right anterior and posterior hepatic ducts join directly to the confluence with the LHD to form the common hepatic duct. The two most common variations in the LHD were segment IV drainage to the left and right hepatic ducts.

Septic Shock: LPS tolerance protects mitochondrial biogenesis and respiration.

ABSTRACT: Mitochondrial dysfunction is a recognized feature of sepsis, characterized by ultrastructural damage, diminished oxidative phosphorylation, and depletion of mitochondrial antioxidant capacity observed in deceased septic patients. Lipopolysaccharide (LPS) tolerance induces a controlled response to sepsis. This study aimed to evaluate the function of tolerant mitochondria after cecal ligation and puncture (CLP)-induced sepsis. Mytochondrial oxygen consumption was determined using polarography. Extraction and quantification of RNA for the expression of Tfam, Nrf-1 and Ppargc-1α; and Respiratory complex activity were measured. CLP-tolerant animals presented preserved respiratory rates of S3 and S4 and a ratio of respiratory control (RCR) compared to CLP non-tolerant animals with reduced oxidative phosphorylation and increased uncoupled respiration. Complex I Vmax was reduced in septic animals; however, CLP animals sustained normal Vmax. Mitochondrial biogenesis was preserved in CLP-tolerant animals compared to the CLP-nontolerant group, likely due to increased TFAM expression. LPS tolerance protected septic animals from mitochondrial dysfunction, favoring mitochondrial biogenesis and preserving mitochondrial respiration and respiratory complex I activity.

Anatomic and Surgical Aspects of Total Pancreatectomy in Swine.

BACKGROUND: The swine is a valuable model for preclinical research and surgical technique training. Induction of Type I diabetes is achieved by total pancreatectomy, therefore these animals may be used in several research studies, including islet transplantation field. Given the lack of information in the literature, the purpose of this work is to describe anatomic aspects of swine pancreas, the total pancreatectomy surgical technique, intra- and postoperative complications and the autopsy results. MATERIAL AND METHODS: Five hybrid male pigs, 20-35 kg, submitted to total pancreatectomy with duodenum, bile duct, and spleen preservation. Postoperatively, daily clinical assessment and capillary blood glucose collection were performed. At the end of the 30-day period or in the occurrence of serious clinical complications, euthanasia and autopsy were performed. RESULTS: The average duration of surgery was 128 minutes, without intraoperative deaths or anesthesia induction failures. The median survival was 6.6 days. Postoperative complications were weight loss (3), emesis (2), constipation (2), abdominal distension (2), diarrhea (1), and loss of appetite (1). All animals were euthanized due to serious complications. Two animals presented surgical complications (duodenal necrosis with gastroparesis and internal hernia with intestinal necrosis). The other 3 animals presented serious clinical complications related to exocrine pancreatic insufficiency due to deficiency of pancreatic enzymes. Glycemic values above 200 mg/dL were found on the first postoperative day and above 300 mg/dL on the seventh day in all animals. CONCLUSION: A model of total pancreatectomy with duodenum, spleen, and bile duct preservation in pigs was established. All animals became diabetic, however, animals without postoperative complications were euthanized due to serious complications related to pancreas exocrine insufficiency.

A mathematical model for optimizing the indications of liver transplantation in patients with hepatocellular carcinoma.

BACKGROUND: The criteria for organ sharing has developed a system that prioritizes liver transplantation (LT) for patients with hepatocellular carcinoma (HCC) who have the highest risk of wait-list mortality. In some countries this model allows patients only within the Milan Criteria (MC, defined by the presence of a single nodule up to 5 cm, up to three nodules none larger than 3 cm, with no evidence of extrahepatic spread or macrovascular invasion) to be evaluated for liver transplantation. This police implies that some patients with HCC slightly more advanced than those allowed by the current strict selection criteria will be excluded, even though LT for these patients might be associated with acceptable long-term outcomes. METHODS: We propose a mathematical approach to study the consequences of relaxing the MC for patients with HCC that do not comply with the current rules for inclusion in the transplantation candidate list. We consider overall 5-years survival rates compatible with the ones reported in the literature. We calculate the best strategy that would minimize the total mortality of the affected population, that is, the total number of people in both groups of HCC patients that die after 5 years of the implementation of the strategy, either by post-transplantation death or by death due to the basic HCC. We illustrate the above analysis with a simulation of a theoretical population of 1,500 HCC patients with tumor size exponentially. The parameter λ obtained from the literature was equal to 0.3. As the total number of patients in these real samples was 327 patients, this implied in an average size of 3.3 cm and a 95% confidence interval of [2.9; 3.7]. The total number of available livers to be grafted was assumed to be 500. RESULTS: With 1500 patients in the waiting list and 500 grafts available we simulated the total number of deaths in both transplanted and non-transplanted HCC patients after 5 years as a function of the tumor size of transplanted patients. The total number of deaths drops down monotonically with tumor size, reaching a minimum at size equals to 7 cm, increasing from thereafter. With tumor size equals to 10 cm the total mortality is equal to the 5 cm threshold of the Milan criteria. CONCLUSION: We concluded that it is possible to include patients with tumor size up to 10 cm without increasing the total mortality of this population.

The impact of hepatitis A virus infection on hepatitis C virus infection: a competitive exclusion hypothesis.

We address the observation that, in some cases, patients infected with the hepatitis C virus (HCV) are cleared of HCV when super-infected with the hepatitis A virus (HAV). We hypothesise that this phenomenon can be explained by the competitive exclusion principle, including the action of the immune system, and show that the inclusion of the immune system explains both the elimination of one virus and the co-existence of both infections for a certain range of parameters. We discuss the potential clinical implications of our findings.

THE OPTIMUM LEVEL OF MELD TO MINIMIZE THE MORTALITY ON LIVER TRANSPLANTATION WAITING LIST, AND LIVER TRANSPLANTED PATIENT IN SÃO PAULO STATE, BRAZIL.

BACKGROUND: After validation in multiple types of liver disease patients, the MELD score was adopted as a standard by which liver transplant candidates with end-stage liver disease were prioritized for organ allocation in the United States since 2002, and in Brazil, since 2006. AIMS: To analyze the mortality profile of patients on the liver transplant waiting list correlated to MELD score at the moment of transplantation. METHODS: This study used the data from the Secretary of Health of the São Paulo State, Brazil, which listed 22,522 patients, from 2006 (when MELD score was introduced in Brazil) until June 2009. Patients with acute hepatic failure and tumors were included as well. We also considered the mortality of both non-transplanted and transplanted patients as a function of the MELD score at presentation. RESULTS: Our model showed that the best MELD score for patients on the liver transplant waiting list associated to better results after liver transplantation was 26. CONCLUSIONS: We found that the best score for applying to liver transplant waiting list in the State of São Paulo was 26. This is the score that minimizes the mortality in both non-transplanted and liver transplanted patients.

Study of laser fluorescence spectroscopy in livers of rats with hypothermic ischemia.

PURPOSE: After partial hepatectomy (PH), the remaining liver (RL) undergoes regenerative response proportional to the host. Limited literature exists on hepatic viability after tissue injury during hypothermic preservation. Spectroscopy measures cellular fluorescence and is explored for tissue characterization and parameter investigation. This study aimed to assess fluorescence analysis (spectroscopy) in evaluating liver viability and its relationship with hepatic tissue regeneration 24 hours after PH. Additionally, we analyzed liver regeneration in RL after 70% partial hepatectomy under hypothermic conditions with laser irradiation. METHODS: Fifty-six Wistar rats were divided into four groups: total non-perfused liver (control), total perfused liver, partial hepatectomy "in situ", and partial hepatectomy "ex situ". Tissue analysis was performed at 0 and 24 hours using spectroscopy with laser devices emitting at 532 (green) and 405 nm (violet). RESULTS: Spectroscopy identified tissue viability based on consistent results with Ki67 staining. The fluorescence spectra and Ki67 analysis displayed similar patterns, linking proliferative activity and absorption intensity. CONCLUSIONS: Fluorescence spectroscopy proves to be promising for real-time analysis of cellular activity and viability. Metabolic activity was observed in groups of live animals and hypothermically preserved samples, indicating cellular function even under blood deprivation and hypothermic conditions.

Multivisceral transplantation of pelvic organs in rats.

Background: Multivisceral transplantation of pelvic organs would be a potential treatment for severe pelvic floor dysfunction with fecal and urinary incontinence, extensive perineal trauma, or congenital disorders. Here, we describe the microsurgical technique of multivisceral transplantation of pelvic organs, including the pelvic floor, in rats. Donor operation: We performed a perineal (including the genitalia, anus, muscles, and ligaments) and abdominal incision. The dissection progressed near the pelvic ring, dividing ligaments, muscles, external iliac vessels, and pudendal nerves, allowing pelvic floor mobilization. The aorta and vena cava were isolated distally, preserving the internal iliac and gonadal vessels. The graft containing the skin, muscles, ligaments, bladder, ureter, rectum, anus and vagina, uterus and ovarian (female), or penile, testis and its ducts (male) was removed en bloc, flushed, and cold-stored. Recipient operation: The infrarenal aorta and vena cava were isolated and donor/recipient aorta-aorta and cava-cava end-to-side microanastomoses were performed. After pelvic floor and viscera removal, we performed microanastomoses between the donor and the recipient ureter, and the rectum and pudenda nerves. The pelvic floor was repositioned in its original position (orthotopic model) or the abdominal wall (heterotopic model). We sacrificed the animals 2 h after surgery. Results: We performed seven orthotopic and four heterotopic transplantations. One animal from the orthotopic model and one from the heterotopic model died because of technical failure. Six orthotopic and three heterotopic recipients survived up to 2 h after transplantation. Conclusion: The microsurgical technique for pelvic floor transplantation in rats is feasible, achieving an early survival rate of 81.82%.

Immunoglobulin G profile in hyperacute rejection after multivisceral xenotransplantation.

INTRODUCTION: Xenotransplantation is a potential solution for the high mortality of patients on the waiting list for multivisceral transplantation; nevertheless, hyperacute rejection (HAR) hampers this practice and motivates innovative research. In this report, we describe a model of multivisceral xenotransplantation in which we observed immunoglobulin G (IgG) involvement in HAR. METHODS: We recovered en bloc multivisceral grafts (distal esophagus, stomach, small intestine, colon, liver, pancreas, and kidneys) from rabbits (n = 20) and implanted them in the swine (n = 15) or rabbits (n = 5, control). Three hours after graft reperfusion, we collected samples from all graft organs for histological study and to assess IgG fixation by immunofluorescence. Histopathologic findings were graded according to previously described methods. RESULTS: No histopathological features of rejection were seen in the rabbit allografts. In the swine-to-rabbit grafts, features of HAR were moderate in the liver and severe in esophagus, stomach, intestines, spleen, pancreas, and kidney. Xenograft vessels were the central target of HAR. The main lesions included edema, hemorrhage, thrombosis, myosites, fibrinoid degeneration, and necrosis. IgG deposition was intense on cell membranes, mainly in the vascular endothelium. CONCLUSIONS: Rabbit-to-swine multivisceral xenotransplants undergo moderate HAR in the liver and severe HAR in the other organs. Moderate HAR in the liver suggests a degree of resistance to the humoral immune response in this organ. Strong IgG fixation in cell membranes, including vascular endothelium, confirms HAR characterized by a primary humoral immune response. This model allows appraisal of HAR in multiple organs and investigation of the liver's relative resistance to this immune response.

Endoscopic features in a model of multivisceral xenotransplantation.

INTRODUCTION: Xenotransplantation and multivisceral transplantation are advanced therapeutic methods that still require a scientific basis. There are no experimental models of multivisceral transplantation available, particularly not the monitoring by endoscopy. Here, we describe the endoscopic features in a model of multivisceral xenotransplantation. METHODS: The distal esophagus, stomach, intestine, colon, liver, pancreas, and the kidneys with a common vascular pedicle were harvested from rabbits and implanted in swine (group I, n = 9) or in rabbits (group II, n = 4). Endoscopy was performed in the stomach, jejunum, and ascending colon at four consecutive time points (immediate after surgery and 10, 90, and 180 min after reperfusion). Lesions were macroscopically graded as mild, moderate, and severe. Biopsies were taken following sacrifice at 180 min after reperfusion. RESULTS: In group I, the stomach, jejunum, and colon manifested a progression of lesions with predominance of mild lesions after 10 min, mild to moderate lesions after 90 min, and moderate to severe lesions after 180 min. In animals from group II, endoscopy showed normal features at all time points after reperfusion. Histopathologic analysis confirmed the diagnosis of hyperacute rejection in group I. Grafts from group II animals presented normal or mild ischemic/reperfusion injury. CONCLUSION: All animals subjected to multivisceral xenotransplantation showed a progression of endoscopic lesions with time after transplantation, while animals subjected to allotransplantation showed no aberrations in endoscopy. We conclude that endoscopy is a useful tool in the assessment of hyperacute rejection of a xenograft.

Absence of bifurcation of the portal vein.

BACKGROUND: Absence of the horizontal segment of the left portal vein (PV) or absence of bifurcation of the portal vein (ABPV) is extremely rare anomaly. The aim of this study was to study the extra-hepatic PV demonstrating the importance of its careful assessment for the purpose of split-liver transplantation. METHOD: Human cadaver livers (n = 60) were obtained from routine autopsies. The cutting plane of the liver consisted of a longitudinal section made immediately on the left of the supra-hepatic inferior vena cava through the gallbladder bed preserving the arterial, portal and biliary branches in order to obtain two viable grafts (right lobe-segments V, VI, VII, and VIII and left lobe-segments II, III, and IV) as defined by the main portal scissure. The PV was dissected out and recorded for application of the liver splitting. RESULTS: The PV trunk has been divided into right and left branch in 50 (83.3%) cases. A trifurcation of the PV was found in 9 (15.2%) cases, 3 (5%) was a right anterior segmental PV arising from the left PV and 6 (10%) a right posterior segmental PV arising from the main PV. ABPV occurred in 1 (1.6%) case. CONCLUSION: Absence of bifurcation of the portal vein is a rare anatomic variation, the surgeon must be cautious and aware of the existence of this exceptional PV anomaly either pre or intra-operatively for the purpose of hepatectomies or even split-liver transplantation.

The potential impact of using donations after cardiac death on the liver transplantation program and waiting list in the state of Sao Paulo, Brazil.

Liver transplantation was first performed at the University of Sao Paulo School of Medicine in 1968. Since then, the patient waiting list for liver transplantation has increased at a rate of 150 new cases per month. Liver transplantation itself rose 1.84-fold (from 160 to 295) from 1988 to 2004. However, the number of patients on the liver waiting list jumped 2.71-fold (from 553 to 1500). Consequently, the number of deaths on the liver waiting list moved to a higher level, from 321 to 671, increasing 2.09-fold. We have applied a mathematical model to analyze the potential impact of using a donation after cardiac death (DCD) policy on our liver transplantation program and on the waiting list. Five thousand one hundred people died because of accidents and other violent causes in our state in 2004; of these, only 295 were donors of liver grafts that were transplanted. The model assumed that 5% of these grafts would have been DCD. We found a relative reduction of 27% in the size of the liver transplantation waiting list if DCD had been used by assuming that 248 additional liver transplants would have been performed annually. In conclusion, the use of DCD in our transplantation program would reduce the pressure on our liver transplantation waiting list, reducing it by at least 27%. On the basis of this model, the projected number of averted deaths is about 41,487 in the next 20 years.

Non heart-beating donors in England.

When transplantation started all organs were retrieved from patients immediately after cardio-respiratory arrest, i.e. from non heart-beating donors. After the recognition that death resulted from irreversible damage to the brainstem, organ retrieval rapidly switched to patients certified dead after brainstem testing. These heart-beating-donors have become the principal source of organs for transplantation for the last 30 years. The number of heart-beating-donors are declining and this is likely to continue, therefore cadaveric organs from non-heart-beating donor offers a large potential of resources for organ transplantation. The aim of this study is to examine clinical outcomes of non-heart-beating donors in the past 10 years in the UK as an way of decreasing pressure in the huge waiting list for organs transplantation.

The optimum level of meld to minimize the mortality on liver transplantation waiting list, and liver transplanted patient in são paulo state, brazil / Melhor nível do meld para minimizar a mortalidade em lista de transplante de fígado no estado de são paulo, brasil

ABSTRACT BACKGROUND: After validation in multiple types of liver disease patients, the MELD score was adopted as a standard by which liver transplant candidates with end-stage liver disease were prioritized for organ allocation in the United States since 2002, and in Brazil, since 2006. AIMS: To analyze the mortality profile of patients on the liver transplant waiting list correlated to MELD score at the moment of transplantation. METHODS: This study used the data from the Secretary of Health of the São Paulo State, Brazil, which listed 22,522 patients, from 2006 (when MELD score was introduced in Brazil) until June 2009. Patients with acute hepatic failure and tumors were included as well. We also considered the mortality of both non-transplanted and transplanted patients as a function of the MELD score at presentation. RESULTS: Our model showed that the best MELD score for patients on the liver transplant waiting list associated to better results after liver transplantation was 26. CONCLUSIONS: We found that the best score for applying to liver transplant waiting list in the State of São Paulo was 26. This is the score that minimizes the mortality in both non-transplanted and liver transplanted patients.

RESUMO RACIONAL: Desde 2002, após validação em múltiplos tipos de hepatopatias, o escore MELD foi adotado como padrão pelo qual os candidatos a transplante de fígado com doença hepática terminal têm sido priorizados para alocação de órgãos nos Estados Unidos, e em 2006 no Brasil. OBJETIVOS: Analisar a mortalidade de pacientes em lista de espera para transplante de fígado correlacionando com o MELD, no momento do transplante. MÉTODOS: Foram utilizados os dados da Secretaria de Saúde do Estado de São Paulo, Brasil, onde foram listados 22.522 pacientes, desde 2006 (quando o escore MELD foi introduzido no Brasil) até junho de 2009. Foram incluídos pacientes com falência hepática e tumores. A mortalidade de pacientes não transplantados e transplantados também foi considerada em função do escore MELD. RESULTADOS: Nosso modelo mostrou que o melhor valor do MELD, em pacientes em lista de espera para transplante e com melhores resultados, foi de 26. Este valor minimiza mortalidade em pacientes não transplantados bem comem pacientes na lista de espera para transplante de fígado. CONCLUSÕES: O escore MELD ótimo para entrar na lista de espera para transplante de fígado, no estado de São Paulo, é em torno de 26. Esse é o valor que minimiza a mortalidade tanto dos pacientes não transplantados em lista de espera, quanto dos submetidos à transplante de fígado.

THE M-RNA, EXPRESSION OF SERCA2 AND NCX1 IN THE PROCESS OF PHARMACOLOGICAL CELL PROTECTION IN EXPERIMENTAL ACUTE PANCREATITIS INDUCED BY TAUROCHOLATE.

BACKGROUND: Intracellular calcium overload is known to be a precipitating factor of pancreatic cell injury in acute pancreatitis (AP). Intracellular calcium homeostasis depends of Plasmatic Membrane Calcium ATPase (PMCA), Sarcoplasmic Endothelial Reticulum Calcium ATPase 2 (SERCA 2) and the Sodium Calcium Exchanger (NCX1). The antioxidant melatonin (Mel) and Trisulfate Disaccharide (TD) that accelerates NCX1 action could reduce the cell damage determined by the AP. AIM: To evaluate m-RNA expressions of SERCA2 and NCX1 in acute pancreatitis induced by sodium taurocholate in Wistar rats pre-treated with melatonin and/or TD. METHODS: Wistar rats were divided in groups: 1) without AP; 2) AP without pre-treatment; 3) AP and Melatonin; 4) AP and TD; 5) AP and Melatonin associated to TD. Pancreatic tissue samples were collected for detection of SERCA2 and NCX1 m-R NA levels by polymerase chain reaction (PCR). RESULTS: Increased m-RNA expression of SERCA2 in the melatonin treated group, without increase of m-RNA expression of the NCX1. The TD did not affect levels of SERCA2 and NCX1 m-RNA expressions. The combined melatonin and TD treatment reduced the m-RNA expression of SERCA2. CONCLUSIONS: The effect of melatonin is restricted to increased m-RNA expression of SERCA2. Although TD does not affect gene expression, its action in accelerating calcium exchanger function can explain the slightest expression of SERCA2 m-RNA when associated with Melatonin, perhaps by a joint action of drugs with different and but possibly complementary mechanisms.

Study of laser fluorescence spectroscopy in livers of rats with hypothermic ischemia

Purpose: After partial hepatectomy (PH), the remaining liver (RL) undergoes regenerative response proportional to the host. Limited literature exists on hepatic viability after tissue injury during hypothermic preservation. Spectroscopy measures cellular fluorescence and is explored for tissue characterization and parameter investigation. This study aimed to assess fluorescence analysis (spectroscopy) in evaluating liver viability and its relationship with hepatic tissue regeneration 24 hours after PH. Additionally, we analyzed liver regeneration in RL after 70% partial hepatectomy under hypothermic conditions with laser irradiation. Methods: Fifty-six Wistar rats were divided into four groups: total non-perfused liver (control), total perfused liver, partial hepatectomy "in situ", and partial hepatectomy "ex situ". Tissue analysis was performed at 0 and 24 hours using spectroscopy with laser devices emitting at 532 (green) and 405 nm (violet). Results: Spectroscopy identified tissue viability based on consistent results with Ki67 staining. The fluorescence spectra and Ki67 analysis displayed similar patterns, linking proliferative activity and absorption intensity. Conclusions: Fluorescence spectroscopy proves to be promising for real-time analysis of cellular activity and viability. Metabolic activity was observed in groups of live animals and hypothermically preserved samples, indicating cellular function even under blood deprivation and hypothermic conditions.

Gastric fundus submucosa as a site for islets transplantation: An experimental study.

BACKGROUND: Islets of Langerhans transplantation is a promising alternative for glycemic control in patients with type 1 diabetes. The graft site is a factor that has large impact on the functioning of this transplant, and the stomach appears to be a promising location. Our objective is to describe a new experimental model for the grafting of Islets of Langerhans in rat stomachs. METHODOLOGY: Islets of Langerhans were extracted from 45 isogenic male rats of the Lewis lineage and transplanted into 9 isogenic rats of the Wistar lineage; 5 in the gastric body submucosa, and 4 in the gastric fundus submucosa. Normoglycemia was defined as two successive measurements of <250 mg/dL. No immunosuppression was used. The two groups glycemia control improvement were compared with t-student test. RESULTS: The results obtained following the transplantation of the islets in 9 rats showed between 995 and 2310 islets transplanted (mean of 1367). The rats from the gastric submucosa group had a better glycemic level improvement, with a confidence equal to 83.94%. CONCLUSION: Islets graft into the gastric fundus submucosa is a viable model with potential for adequate glycemic control. This model gives potential for new perspectives and future studies in this area.