Dermatological Complications of COVID 19 Vaccines: An Updated Review

Vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the 2019 coronavirus disease (COVID-19) pandemic, have been rapidly developed and authorized. However, re-cent studies showed that COVID-19 vaccination is associated with a wide range of dermatological reactions. The most prevalent adverse dermatological reaction observed in observational studies was a delayed large lo-cal reaction (DLRs), which is characterized by the appearance of an erythematous and edematous patch at the injection site four days or more after vaccination. Most of these reactions are common in females and resolve spontaneously within a few days to a weak. The second dose of the vaccine was associated with a higher inci-dence of cutaneous reactions compared to the first dose but milder in intensity. It seems that the Moderna vaccine is associated with a higher incidence of these adverse events compared to the Pfizer vaccine. Fur-thermore, mRNA vaccines had a higher incidence than vector-based and inactivated vaccines. There is a lack of evidence regarding the side events of the Johnson & Janssen vaccine. Further long-term, multicenter studies are required to compare these vaccines and highlight the best practice in managing these reactions.

A network pharmacology and molecular docking approach in the exploratory investigation of the biological mechanisms of lagundi (Vitex negundo L.) compounds against COVID-19

Coronavirus disease 2019 (COVID-19) is an inflammatory and infectious disease caused by severe acute respiratory syndrome coronavirus 2 virus with a complex pathophysiology. While COVID-19 vaccines and boosters are available, treatment of the disease is primarily supportive and symptomatic. Several research have suggested the potential of herbal medicines as an adjunctive treatment for the disease. A popular herbal medicine approved in the Philippines for the treatment of acute respiratory disease is Vitex negundo L. In fact, the Department of Science and Technology of the Philippines has funded a clinical trial to establish its potential as an adjunctive treatment for COVID-19. Here, we utilized network pharmacology and molecular docking in determining pivotal targets of Vitex negundo compounds against COVID-19. The results showed that significant targets of Vitex negundo compounds in COVID-19 are CSB, SERPINE1, and PLG which code for cathepsin B, plasminogen activator inhibitor-1, and plasminogen, respectively. Molecular docking revealed that α-terpinyl acetate and geranyl acetate have good binding affinity in cathepsin B; 6,7,4-trimethoxyflavanone, 5,6,7,8,3',4',5'-heptamethoxyflavone, artemetin, demethylnobiletin, gardenin A, geranyl acetate in plasminogen; and 7,8,4-trimethoxyflavanone in plasminogen activator inhibitor-1. While the results are promising, these are bound to the limitations of computational methods and further experimentation are needed to completely establish the molecular mechanisms of Vitex negundo against COVID-19.

Epithelial-Myoepithelial carcinoma of the lacrimal gland - Case report and review of literature

Objective@#To describe the clinicopathologic features and outcome of a patient with epithelial-myoepithelial carcinoma of the lacrimal gland who underwent modified lateral orbitotomy with en toto removal of the lesion and adjuvant radiotherapy.@*Methods@#This is a case report.@*Results@#A 31-year-old Filipino male seafarer presented with a 2-month history of an enlarging left superotemporal orbital mass and inferonasal displacement of the globe. Magnetic resonance imaging revealed a superotemporal extraconal mass within the lacrimal sac fossa with evidence of osseous infiltration of the superolateral orbital rim. Modified lateral orbitotomy was performed with en toto removal of the lesion and the clinically infiltrated adjacent lateral bony margin. Histopathologic diagnosis of epithelial-myoepithelial carcinoma of the lacrimal gland was made based on the classic and distinct biphasic morphology and was confirmed with immunohistochemistry studies (cytokeratin-7, S-100, and p63). Systemic surveillance using positron emission tomography and computed tomography scan with contrast revealed no evidence of regional or distant metastasis. Adjuvant radiotherapy of the orbital area was performed for increased local control. Twelve months postoperatively, the patient showed no evidence of tumor recurrence.@*Conclusion@#Epithelial-myoepithelial carcinoma of the lacrimal gland is a rare condition, and this is the first documented case from the Philippines. Accurate diagnosis is necessary for appropriate treatment. It should be included in the differential diagnosis of infiltrative lesions in the lacrimal gland fossa.

Intravitreous chemotherapy as adjuvant rteatment for vitreous seeding in retinoblastoma: A Philippine tertiary hospital experience

Background@#Intravitreal chemotherapy has been an effective addition in treating vitreous seeding in retinoblastoma. However, it was only in 2020 that it was used in the Philippines. There is no literature on its use in multiple Filipino retinoblastoma patients. @*Objectives@#To describe the clinical course of the four patients who are the first to undergo intravitreal chemotherapy for vitreous seeding of retinoblastoma in the Philippine tertiary hospital.@*Methods@#A case series of four eyes of four patients with retinoblastoma who underwent intravitreous injection of melphalan and topotecan for vitreous seeding at the Department of Ophthalmology and Visual Sciences of a Philippine tertiary hospital. @*Results@#Two eyes, with International Intraocular Retinoblastoma Classification (IIRC) Group C with vitreous seeding, responded well to intravitreous melphalan and topotecan. One eye had recurrent vitreous seeding despite 10 intravitreal injections. One eye with IIRC Group E, did not respond to intravitreous chemotherapy and was eventually enucleated. This is the first case series on the local use of intravitreous chemotherapy in the country for vitreous seeding in retinoblastoma. The control of 50% achieved in this case series is lower than in other series due to longer treatment interval from poor follow-up and the presence of advanced disease.@*Conclusion@#The use of intravitreous melphalan and topotecan can be an effective adjuvant for systemic chemotherapy in controlling vitreous seeding in eyes with IIRC Group C. It is not effective in controlling IIRC Group E disease.

Prevalence of Depression in Vitiligo Patients-A Systematic Review and Meta-Analysis

Background: the incidence of depression in vitiligo patients ranges from 10% to over 60%, depending on the outcome measures, sample size and study population. The purpose is to estimate the prevalence of depression among vitiligo patients by conducting a systematic review and metanalysis of published studies. Methods: we conducted a literature search on Medline via PubMed, Scopus, web of science and Cochrane library. Results: 35 studies finally met our inclusion criteria. Our findings showed that the overall prevalence of depression among patients with vitiligo was 35 % (26%-45). Moreover, we observed a variation in the prevalence based on the used tool. For example, the GHQ revealed 30% (20%-39%) and the HDRS re-vealed 50% (44% - 57%). Our analysis demonstrated no significant differences between vitiligo and healthy cases in terms of HDRS and DBI. Moreover, there was no significant differences between vitiligo and psoriasis in terms of GHQ and BDI scores. Conclusion: in conclusion the current evidence suggests that patients with vitiligo have a high risk and prevalence of depression, different questionnaires have yielded variable prevalence due to the different domains and validation method.

A pilot study of the impact of Vitamin C supplementation with neoadjuvant chemoradiation on regulators of inflammation and carcinogenesis in esophageal cancer patients

Aims: Vitamin C plays a role in chemoprevention in cancer treatment, and Vitamin C modulates many regulators of inflammation in in vitro studies. The aim of this study is to assess the effect of Vitamin C supplementation with neoadjuvant chemoradiation in esophageal adenocarcinoma on the nuclear factor-kappa B (NF-κB) and associated cytokines. Materials and Methods: A total of 20 patients undergoing multimodal treatment for esophageal adenocarcinoma were randomized to receive Vitamin C (1000 mg/day) orally for 4 weeks or no supplementation. Pre- and post-Vitamin C endoscopic biopsies were used for the study of NF-κB activity and cytokine analysis. Results: NF-κB activity along with cytokines was activated in the cancer tissue pretreatment. Down-regulation in NF-κB activity was observed in 25% of cases, two from the Vitamin C arm posttreatment. There was a significant reduction in cytokines levels in the cancer group, and this effect was more pronounced in the Vitamin C group (P < 0.05). Conclusions: Vitamin C supplementation had a mild protective effect in modulating of regulators of inflammation and carcinogenesis. Further studies with larger numbers of endpoints are needed to evaluate its effect on modulation of chemoradiation responses.

Collagenase Clostridium Histolyticum Injection for Dupuytren Contracture: 2-Year Follow-up

BACKGROUND: Dupuytren disease is characterized by the development of palmar fibrous tissue that can lead to fixed flexion contracture (FFC) and contribute to functional loss of the involved digits. Our goal was to investigate rates of contracture resolution and recurrence in patients who underwent enzymatic fasciotomy for Dupuytren contracture consisting of collagenase clostridium histolyticum (CCH) injection followed by passive manipulation combined with splinting and home-based therapy. METHODS: We prospectively enrolled 34 patients (44 metacarpophalangeal [MCP] and 33 proximal interphalangeal [PIP] joints) treated by one orthopaedic hand surgeon between November 2010 and November 2014. On day 1, CCH was injected into a palpable fibrous cord of the involved fingers. The next day, the finger was passively extended to its maximal corrective position. FFC was measured for each joint before injection and immediately after manipulation. Patients were instructed to wear an extension splint at night and perform stretching exercises at home and were re-evaluated at 6 weeks, 4 months, 1 year, and 2 years. Resolution was defined as improvement of contracture to ≤ 5° of neutral. Recurrence was defined as an increase in FCC of ≥ 20° after treatment. RESULTS: Immediate contracture resolution occurred in 42 of 44 MCP joints (p < 0.001), improving from 50° to 1.5°, and in 14 of 33 PIP joints (p = 0.182), improving from 44° to 16°. Four joints had recurrence within 6 weeks. Of the 48 joints with minimum 4-month follow-up (mean, 26 months), 12 had recurrence at 2-year follow-up (MCP, 6; PIP, 6). At 2-year follow-up, MCP and PIP contractures measured 17° and 35.5°, respectively. Older age and multiple digit involvement were associated with higher recurrence rates. CONCLUSIONS: CCH offers a safe, nonoperative option to correct FCC in Dupuytren disease with greater success for MCP joints compared to PIP joints. There is a tendency of reoccurrence within 2 years of treatment. Further investigation is needed to determine optimal timing of repeat CCH injection to improve upon or extend the period of contracture resolution.

Predictive biomarkers in precision medicine and drug development against lung cancer / 癌症

The molecular characterization of various cancers has shown that cancers with the same origins, histopathologic diagnoses, and clinical stages can be highly heterogeneous in their genetic and epigenetic alterations that cause tumorigenesis. A number of cancer driver genes with functional abnormalities that trigger malignant transformation and that are required for the survival of cancer cells have been identified. Therapeutic agents targeting some of these cancer drivers have been successfully developed, resulting in substantial improvements in clinical symptom amelioration and outcomes in a subset of cancer patients. However, because such therapeutic drugs often benefit only a limited number of patients, the successes of clinical development and applications rely on the ability to identify those patients who are sensitive to the targeted therapies. Thus, biomarkers that can predict treatment responses are critical for the success of precision therapy for cancer patients and of anticancer drug development. This review discusses the molecular heterogeneity of lung cancer pathogenesis; predictive biomarkers for precision medicine in lung cancer therapy with drugs targeting epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), c-ros oncogene 1 receptor tyrosine kinase (ROS1), and immune checkpoints; biomarkers associated with resistance to these therapeutics; and approaches to identify predictive biomarkers in anticancer drug development. The identification of predictive biomarkers during anticancer drug development is expected to greatly facilitate such development because it will increase the chance of success or reduce the attrition rate. Additionally, such identification will accelerate the drug approval process by providing effective patient stratification strategies in clinical trials to reduce the sample size required to demonstrate clinical benefits.

Reasons for inpatients not to seek clarity at Dr George Mukhari Academic Hospital, Pretoria

Background: Healthcare practitioners should provide patients with information regarding their clinical conditions. Patients should also feel free to seek clarity on information provided. However; not all patients seek this clarity. Objectives: To explore the reasons inpatients gave for not seeking clarity on information that was received but not understood. Methods: This was a qualitative arm of a larger study; titled 'Are inpatients aware of the admission reasons and management plans of their clinical conditions? A survey at a tertiary hospital in South Africa'; conducted in 2010. Of the 264 inpatients who participated in the larger study; we extracted the unstructured responses from those participants (n = 152) who had indicated in the questionnaire that there was information they had not understood during their encounter with healthcare practitioners; but that they had nonetheless not sought clarity.Data were analysed thematically. Results: Themes that emerged were that inpatients did not ask for clarity as they perceived healthcare practitioners to be 'too busy'; aloof; non-communicators and sometimes uncertain about patients' conditions. Some inpatients had unquestioning trust in healthcare practitioners;whilst others had experiences of bad treatment. Inpatients had poor self-esteem; incapacitating clinical conditions; fear of bad news and prior knowledge of their clinical conditions. Some inpatients stated that they had no reason for not seeking clarity. Conclusion: The reasons for not seeking clarity were based on patients' experiences with the healthcare practitioners and their perceptions of the latter and of themselves. A programme should be developed in order to educate inpatients on effective communication with their healthcare practitioners

Evaluation of endoscopically obtained duodenal biopsy samples from cats and dogs in an adapter-modified Ussing chamber

This study was conducted to evaluate an adapter-modified Ussing chamber for assessment of transport physiology in endoscopically obtained duodenal biopsies from healthy cats and dogs, as well as dogs with chronic enteropathies. 17 duodenal biopsies from five cats and 51 duodenal biopsies from 13 dogs were obtained. Samples were transferred into an adapter-modified Ussing chamber and sequentially exposed to various absorbagogues and secretagogues. Overall, 78.6% of duodenal samples obtained from cats responded to at least one compound. In duodenal biopsies obtained from dogs, the rate of overall response ranged from 87.5% (healthy individuals; n = 8), to 63.6% (animals exhibiting clinical signs of gastrointestinal disease and histopathological unremarkable duodenum; n = 15), and 32.1% (animals exhibiting clinical signs of gastrointestinal diseases and moderate to severe histopathological lesions; n = 28). Detailed information regarding the magnitude and duration of the response are provided. The adapter-modified Ussing chamber enables investigation of the absorptive and secretory capacity of endoscopically obtained duodenal biopsies from cats and dogs and has the potential to become a valuable research tool. The response of samples was correlated with histopathological findings.

Evaluation of Leukocyte and Bacterial Interference in Point-of-Care Human Chorionic Gonadotropin Tests

No abstract available.

Sequential chemotherapy and radiotherapy as sandwich therapy for the treatment of high risk endometrial cancer / 부인종양

OBJECTIVE: The purpose of this retrospective study was to assess the tolerability and efficacy of sequential chemotherapy and radiotherapy for the treatment of high risk endometrial cancer. METHODS: We conducted a retrospective study of previously untreated high risk endometrial cancer patients who received sequential chemotherapy and radiotherapy in accordance with the sandwich approach from June 2008 until June 2011. High risk endometrial cancer patients underwent complete surgical staging followed by adjuvant therapy encompassing sequential chemotherapy, radiation therapy and consolidation chemotherapy. RESULTS: The study analysis comprised 32 endometrial cancer patients. All subjects were treated with carboplatin and paclitaxel chemotherapy; currently, 186 cycles have been administered and 94% of patients have completed the planned number of cycles. Grade 3 neutropenia developed in 1 (3.1%) patient; there was no incidence of grade 4 neutropenia. Moreover, we observed grade 3 anemia in four (12.5%) patients and grade 4 anemia in one (3.1%) patient. One (3.1%) patient developed grade 3 thrombocytopenia; grade 4 thrombocytopenia was not observed. Five patients exhibited progressive disease, three of whom have since expired; mean progression free survival and follow-up were 17.4 months and 18.9 months, respectively. CONCLUSION: The preliminary results from our study suggest that the sandwich approach to treating high risk endometrial cancer patients is feasible. Hematologic toxicity was well tolerated and non-hematologic toxicity was mild and easily managed. Further study of this novel regimen in a larger patient population with extended follow-up is necessary.

case of undiagnosed coeliac disease resulting in secondary hyperparathyroidism and presenting with giant cell granuloma [Brown's tumor]

Coeliac Disease is an autoimmune disease. It affects genetically pre-disposed individuals, leading to mal absorption of nutrients and patients presenting with a multitude of symptoms, which can sometimes go undiagnosed. We present a case where coeliac disease was identified as the cause of a giant cell tumor of hyperparathyroidism in the mandible

Clinical epidemiology of retinoblastoma at the Philippine General Hospital:1998-2008

Objective@#This study determined the clinical characteristics of retinoblastoma (RB) from 1998 to 2008 and compared the epidemiological and clinical patterns with those of the period from 1967 to 2001.@*Methods@#We reviewed the clinical records of 152 patients with RB from 1998 to 2008 in terms of demographic and ophthalmological data and clinical staging or classification.@*Results@#Sixty-three percent of cases were unilateral and 37% were bilateral. Three (3%) of 95 unilateral cases and 7 (12%) of 57 bilateral cases had family history of RB (p = 0.038). The mean age at onset was 17.8 months for unilateral and 7.4 months for bilateral cases, while the mean age at diagnosis was 26.4 months and 13.7 months respectively. The delay from onset to diagnosis was 69% in unilateral and 56% in bilateral RB groups. Financial cost (71.4%) was the leading reason for delay, followed by misdiagnosis (24.5%), and inaccessibility of medical facility (2.0%). The most common manifestations were leukocoria (77%), extraocular findings of orbital mass (9%), and proptosis (6%). Advanced intraocular stage was seen in 63 – 71.6% among those with unilateral and 56 – 60% in those with bilateral tumor.@*Conclusion@#The onset of disease had not changed over the years, but patients in general were brought earlier for consultation. Most cases presented in the advanced stage. Decreasing the occurrence of extraocular RB through early consultation and treatment can improve patient survival.

Screening for intraocular metastases in patients with breast carcinoma

@#ACCORDING to the Department of Health (DOH), cancer ranks third among the leading causes of morbidity and mortality in the Philippines, after infectious and cardiovascular diseases.1 The DOH–Rizal Cancer Registry and the Philippine Cancer Society–Manila Cancer Registry listed breast cancer as the most commonly diagnosed type of cancer in 2006. The Cancer Institute of the University of the Philippines–Philippine General Hospital (UP-PGH) also reported breast cancer as the most common carcinoma seen at the outpatient clinic, with more than 10,000 cases each year. Although intraocular metastasis most frequently originates from the breast,2 it was once a rarity overall. Perls was the first to describe intraocular metastasis in 1872,3 and a subsequent article by Godtfredsen reported its incidence at 0.07%.4 However, post-mortem studies have shown that among patients who died of cancer, 12.2% had histopathologic evidence of intraocular metastases.5 This was supported by another study involving donor eyes with a prevalence of 12.6%.6 Two studies determined the frequency of intraocular metastases from breast carcinoma. Mewis and Young7 examined 250 patients with breast carcinoma and detected 67 (26.8%) positive cases. They also reported that 9% of patients who were asymptomatic also had intraocular metastases. Wiegel and colleagues performed a prospective screening program for 120 asymptomatic patients with disseminated breast carcinoma and found 6 (5%) with intraocular metastases.8 These studies showed that metastases to the eye may not be as rare as once thought.

Chemotherapy and patient co-morbidity in ventral site hernia development / 부인종양

OBJECTIVE: The risk factors associated with early ventral site hernia development following cancer surgery are ill defined and associated with an undetermined incidence. METHODS: We analyzed 1,391 gynecologic cancer patient charts to identify the number of post-operative ventral site hernias over a nearly 6 year period. The following study variables were noted for evaluation: patient demographics, disease co-morbidity (hypertension, cardiovascular disease, diabetes), body mass index (BMI), treatment (e.g., chemotherapy regimen), intra-operative (e.g., bleeding) and postoperative (e.g., infection) complications, time to hernia development and length of hospital stay. RESULTS: Twenty-six gynecologic cancer patients who developed a post-operative ventral hernia and subsequently underwent herniorrhaphy by our gynecologic oncology service were identified. The patient group's overall time to initial hernia development was 11.23 months. Following a multiple regression analysis, we found that treatment (e.g., bevacizumab, liposomal doxorubicin or radiotherapy associated with compromised wound healing [p=0.0186] and disease co-morbidity [0.0432]) were significant prognostic indicators for an accelerated time to hernia development. Moreover, five patients underwent treatment associated with compromised wound healing and also had disease co-morbidity. In this sub-group, post-operative hernia development occurred more rapidly (3.8 months) than the overall group of patients. BMI and age did not impact time to hernia development (p>0.05). CONCLUSION: In the present gynecologic cancer patient series, a tendency for early post-operative hernia development appeared to coincide with treatment associated with compromised wound healing and disease co-morbidity. Gynecologic cancer surgeons should anticipate this potential complication and consider employing prophylactic intra-operative mesh to potentially prevent this condition.

Diabetes outcomes in specialist and general practitioner settings in Singapore: challenges of right-siting

The Singapore public healthcare system has increasingly used the term "right-siting" to describe the principle that stable chronic disease patients should be managed in primary care rather than specialist settings. The majority of primary healthcare providers in Singapore are general practitioners (GPs). The aims of this paper were to measure the quality of diabetes care in specialist and GP settings, and assess right-siting efforts in a tertiary centre in Singapore. Three hundred eighty-three consecutive patients with type 2 diabetes referred to the Singapore General Hospital Diabetes Centre (SGH DBC) between January and March 2005 were analysed. At the first visit, 51 patients (13.3%) were classified as inappropriate referrals and discharged back to the referral source or to primary care. After 12 months, 136 patients (group A = 35.5%) remained on follow-up at SGH DBC. In these patients, significant improvements were seen in mean HbA1c but not blood pressure (BP) or low density lipoprotein-cholesterol (LDL-C). One hundred twenty-eight (group B = 33.4%) patients were discharged from DBC within the 12 months of the study period. Mean follow-up duration in group B was 5.5 months and HbA1c, blood pressure and LDL-cholesterol had improved significantly in these patients. Glycaemic control of group B patients at the time of discharge was significantly better than group A at 12 months (mean HbA1c = 7.15% vs 8.16%; P <0.001). More than half (55.6%) of group B patients achieved HbA1c targets compared to 32.4% from group A (P <0.001). Although mean BP and LDL-C levels fell in group B patients, the percentage of patients achieving BP and LDL-C targets did not improve significantly in both groups. From August 2005 to January 2008, GPs participating in SingHealth's Delivering on Target (DOT) programme enrolled 579 patients under their care for additional diabetic counselling by community nurse educators. Pre- and post-programme HbA1c results were submitted for 370 patients (64%). Mean HbA1c levels of these patients decreased from 8.23% to 7.32% (P <0.001). The proportion of patients who achieved HbA1c <7% increased from 26% to 51% (P <0.01). However, BP and LDL-C levels did not improve. It is difficult to base referral or discharge decisions solely on these indicators. Our studies show that both in the specialist and GP settings, significant improvements in HbA1c are seen. Results for BP and LDL-C, however, showed little improvement. Some degree of rightsiting was seen at SGH DBC with discharged patients showing greater improvements than patients who were retained. However, >30% of patients remained in SGH DBC despite achieving HbA1C targets. Our results indicate the need for better strategies to address the underlying obstacles to right-siting. Of greater concern, the lack of improvement in BP and LDL-C indicates a high degree of clinical inertia to these issues among specialists and GPs treating diabetes in Singapore.

Degeneration of primary afferent terminals following brachial plexus extensive avulsion injury in rats / Degeneración de los terminales aferentes primarios de rata luego de lesión extensa por avulsión del plexo braquial

Important breakthroughs in the understanding regeneration failure in an injured CNS have been made by studies of primary afferent neurons. Dorsal rhizotomy has provided an experimental model of brachial plexus (BP) avulsion. This is an injury in which the central branches of primary afferents are disrupted at their point of entry into the spinal cord, bringing motor and sensory dysfunction to the upper limbs. In the present work, the central axonal organization of primary afferents was examined in control (without lesion) adult Wistar rats and in rats subjected to a C3-T3 rhizotomy. Specific sensory axon subtypes were recognized by application of antibodies to the calcitonin gene-related peptide (CGRP), the P2X3 purinoreceptor, the low-affinity p75-neurotrophin receptor and the retrograde tracer cholera toxin subunit beta (TCbeta ). Other subtypes weres labeled with the lectin Griffonia simplicifolia IB4. Using immunohistochemistry and high resolution light microscopy, brachial plexus rhizotomy in adult rats has proven a reliable model for several neural deficits in humans. This lesion produced different degrees of terminal degeneration in the several types of primary afferents which define sub-populations of sensitive neurons. Between the C6 and C8 levels of the spinal cord,,deafferentation was partial for peptidergic GCRP-positive fibers, in contrast with elimination of non peptidergic and myelinated fibers. Dorsal rhizotomy has provided an adequate experimental model to study sensory alterations such as acute pain and allodynia as well as factors that affect regeneration into the CNS., Therefore, the differential deafferentation response must be considered inr the evaluation of therapies for nociception (pain) and regeneration for brachial plexus avulsion. The anatomical diffierences among the primary afferent subtypes also affect their roles in normal and damaged conditions.

El uso de las neuronas sensoriales primarias ha aportado avances en el entendimiento de las razones por las cuales falla la regeneración cuando el sistema nervioso central (SNC) es dañado. La rizotomía dorsal se puede usar como un modelo experimental de las lesiones por avulsión del plexo braquial, una lesión en la cual son desprendidas, en su punto de entrada en la médula espinal, las ramas centrales de los aferentes primarios causando una disfunción motora y sensorial grave e irreversible del miembro superior. En el presente trabajo, se examinó la organización central de los aferentes primarios en ratas Wistar adultas. Éstas fueron divididas en controles normales no lesionados y en animales rizotomizados entre los niveles cervical 3 y torácico 3 (C3-T3). Se estudió la deaferentación de los subtipos de axones sensoriales utilizando anticuerpos específicos contra el péptido relacionado con el gen de la calcitonina (CGRP), el receptor purinérgico (P2X3), el receptor de baja afinidad p75 para el factor de crecimiento nervioso (NGF) y contra la subunidad ®de la toxina de cólera (TCbeta ). Otro subtipo fue marcado con la lectina Griffonia simplicifolia IB4. La inmunohistoquímica y la microscopía óptica de alta resolución demostraron que el modelo animal de rizotomía completa del plexo braquial reproduce diversos déficit observados en las lesiones humanas. Esta lesión produce diferentes grados de degeneración terminal entre los diversos tipos de aferentes primarios que definen subpoblaciones de neuronas sensoriales. En los niveles de la médula espinal estudiados (entre C6 y C8), la deaferentación fue parcial para las fibras peptidérgicas GCRPpositivas, en contraste con la eliminación de las fibras no peptidérgicas y las mielinizadas. La rizotomía dorsal es un modelo experimental apropiado para estudiar las alteraciones sensoriales como el dolor agudo y la alodinia, así como los factores que podrían afectar la regeneración en el SNC. Por tanto, la respuesta de deaferentacion diferencial debe ser tenida en cuenta para la evaluación de terapias antinociceptivas y regenerativas tras la avulsión del plexo braquial. Se discute la anatomía de los subtipos de aferentes primarios y su papel en condiciones normales y después de la lesión.